Iron core assembly of direct current coil control contactor
By optimizing the end shape design of the dynamic and static iron core and adopting a convex and concave trapezoidal structure, the problems of blocking and interference of the DC coil control contactor under high frequency operation are solved, and the reliability and guidance of the core assembly are achieved, avoiding the degradation of the coil performance.
Patent Information
- Application Number
- CN202422340019.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2034-09-25
AI Technical Summary
The core components of the existing DC coil control contactor are prone to action blockage and interference under high frequency operation, which affects reliability, especially in cases of frequent movements, which cannot ensure smoothness of action.
By optimizing the end shape design of the dynamic and static iron core, the convex and concave trapezoidal structure is adopted to ensure that the dynamic iron core is not obstructed during the absorption and engagement process, and the length of the dynamic iron core remains unchanged. The height of the combined static iron core is increased to ensure guidance and tight fit.
The smooth movement of the moving core without changing the inner diameter of the coil frame and the length of the moving core is achieved, avoiding the problem of reducing the number of coil turns and temperature rise, and improving the reliability and guidance of the contactor.
Smart Images
Figure CN223206184U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of DC coil control contactors, in particular to an iron core component of a DC coil control contactor. Background Art
[0002] Existing DC coil-controlled contactors feature an iron core and armature made of a single solid piece of material, rather than silicon steel sheets. The core is typically an I-shaped core assembly. DC coil-controlled contactors offer excellent stability and reliability, with a lifespan of hundreds of thousands of operations or more.
[0003] The contactor's core assembly consists of a moving iron core and a stationary iron core. The moving iron core is riveted to the clamping plate and clamped into the contact support slot, forming an integral structure. The stationary iron core is riveted to the lower base of the yoke. A coil bobbin wrapped with enameled copper wire is placed over the stationary iron core and installed within the yoke. When the contactor coil is energized, a magnetic field is generated within the coil, and the stationary iron core generates electromagnetic attraction. This sufficient attraction causes the moving iron core to overcome the reaction force of the spring and move downward within the coil bobbin to engage with it.
[0004] To enhance the guiding properties of the moving iron core during energization, it is typically made longer. When the contactor control circuit is de-energized, the moving iron core should extend more than halfway into the coil bobbin. Traditional core assemblies typically design both the moving and static iron cores as simple cylinders. Because the moving iron core must drive the contact support to slide within the upper cover when energized, a 0.1-0.3mm gap must be left between the contact support and the sliding slot in the upper cover to minimize resistance to contact support sliding. When the contactor is mounted vertically with overtravel and open distance set, the contact support will rotate the moving iron core clockwise a certain distance due to gravity and the presence of the gap. Because the end face of the moving iron core is farthest from the center of rotation, assuming a 0.2mm gap between the contact support and the sliding slot, the end face of the moving iron core will be offset downward by approximately 0.35mm. If a 0.3mm gap is set between the moving iron core and the inner wall of the coil bobbin, interference will occur.
[0005] Contactors must meet frequencies up to 3,600 times per hour. When used in applications requiring higher operating frequencies, the frequently actuated contactor core assembly must maintain reliable operation. Therefore, it is essential to ensure that when the contactor is properly installed and used, the core moves smoothly within the coil frame without obstruction. Utility Model Content
[0006] The purpose of this utility model is to overcome the defects of the above-mentioned prior art and provide an iron core assembly for a DC coil-controlled contactor. Without changing the inner diameter of the coil frame and the length of the moving iron core, the contactor can be operated more safely and reliably, and the iron core can move smoothly and without obstruction in the coil frame.
[0007] The purpose of the utility model can be achieved through the following technical solutions:
[0008] A core assembly of a DC coil-controlled contactor includes a matching moving iron core and a stationary iron core, characterized in that the longitudinal cross-section of the end of the moving iron core is a convex trapezoid, including an upper end face, a lower end face and a step face, and the longitudinal cross-section of the end of the stationary iron core is a concave trapezoid, including an opening face and a bottom face.
[0009] Furthermore, the movable iron core is riveted to the clamping plate and clamped in the clamping slot of the contact support to form an integral structure with the contact support.
[0010] Furthermore, a gap is left between the contact support and the sliding slot.
[0011] Furthermore, the static iron core is riveted to the lower base plate of the magnetic yoke.
[0012] Furthermore, a gap is left between the moving iron core and the inner wall of the coil frame.
[0013] Furthermore, the coil skeleton is sleeved on the static iron core and installed in the magnetic yoke.
[0014] Furthermore, when the contactor control circuit is not energized, the movable iron core extends into the coil skeleton to a length exceeding half of its operating stroke.
[0015] Furthermore, the sum of the outer diameter of the lower end surface of the movable iron core end and the maximum downward offset dimension of the step surface is smaller than the inner diameter of the opening surface of the static iron core end.
[0016] Furthermore, the sum of the outer diameter of the upper end surface of the end portion of the moving iron core and the maximum downward offset dimension of the upper end surface is smaller than the inner diameter of the bottom surface of the end portion of the static iron core.
[0017] Furthermore, the height of the protruding trapezoid at the end of the moving iron core is greater than or equal to the height of the recessed trapezoid at the end of the static iron core.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] 1. The utility model optimizes the design of the end shape of the moving and static iron cores without shortening the length of the moving iron core. Combined with the design of the concave and convex trapezoid, it ensures that the moving iron core is unobstructed and does not interfere during the attraction process, ensuring that the moving iron core can have good guidance when working. The design of the height size of the concave and convex trapezoid ensures that after the moving iron core is attracted, its attraction surface can be tightly fitted and is the end face with the largest area.
[0020] 2. The present invention avoids the enlargement of the inner and outer diameters of the coil skeleton by optimizing the shape design at the ends of the dynamic and static iron cores, fundamentally avoids the reduction of the number of coil turns and thus the reduction of the coil resistance, and indirectly ensures the reasonable temperature rise of the coil during operation. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a structural diagram of an iron core assembly of a DC control coil proposed in the present invention;
[0022] Figure 2 This is a structural diagram of a moving iron core and a static iron core of an iron core assembly of a DC control coil proposed in the present invention;
[0023] Figure 3 This is a schematic structural diagram of a downward biased moving iron core of an iron core assembly of a DC control coil proposed by the present invention.
[0024] Legend: 1. Moving iron core; 2. Stationary iron core; 3. Coil skeleton; 4. Contact support; 5. Sliding groove. DETAILED DESCRIPTION
[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.
[0026] This embodiment provides a core assembly of a DC control coil, such as Figure 1 As shown, it includes a moving iron core 1 and a static iron core 2. The length of the moving iron core 1 is 29 mm, and the longitudinal section of its end is a convex trapezoid. The trapezoid height H1 is 4 mm, including an upper end face, a lower end face and a step face. The contact end face positions of the moving iron core 1 and the static iron core 2 remain unchanged, the height of the static iron core 2 is doubled, and the longitudinal section of its end is a concave trapezoid, including an opening face and a bottom face.
[0027] The moving iron core 1 is riveted to the clamping plate and clamped into the slot of the contact support 4, forming an integral structure with the contact support 4. A gap is left between the moving iron core 1 and the inner wall of the coil bobbin 3. A gap is left between the contact support 4 and the sliding slot 5. The stationary iron core 2 is riveted to the lower base plate of the magnetic yoke. The coil bobbin 3 is sleeved over the stationary iron core 2 and installed within the magnetic yoke.
[0028] Regarding the moving iron core, to enhance its guidance during engagement, it is lengthened. When the contactor control circuit is de-energized, the moving iron core 1 extends into the coil bobbin 3 by more than half its travel. While the length of the moving iron core 1 remains unchanged to ensure guidance, the outer diameter of its ends is reduced, giving them a convex trapezoidal cross-section. Regarding the stationary iron core, the height of the stationary iron core 2 is increased, while the engagement surface remains unchanged. Its ends are designed to have a concave trapezoidal cross-section.
[0029] Considering the core assembly as a whole, such as Figure 2 As shown, the outer diameter of the upper end face of the protruding trapezoid at the end of the moving iron core 1 is φB, the outer diameter of the lower end face is φA, the inner diameter of the bottom face of the recessed trapezoid at the end of the static iron core 2 is φD, and the inner diameter of the opening face is φC. After the contactor is installed, the maximum downward offset dimension of the upper end face of the moving iron core 1 is E, and the maximum downward offset dimension of the step face of the moving iron core is F. Then, φA+F<φC, φB+E<φD. The design of these four sizes ensures that the moving iron core has no obstruction during the attraction process. Combined with the design of the concave and convex trapezoid, it has better guidance when it is attracted. Furthermore, the height of the protruding trapezoid at the end of the moving iron core 1 is H1, and the height of the recessed trapezoid at the end of the static iron core 2 is H2, H1≥H2. The design of the height dimension of the concave and convex trapezoid ensures that after the moving iron core is attracted, its attraction surface can be tightly fitted, and it is the end face with the largest area.
[0030] In this embodiment, the gap between the contact support 4 and the sliding groove 5 is 0.2mm. At this time, the step surface of the moving iron core 1 will only be offset downward by about 0.25mm. If a gap of 0.3mm is preset between the moving iron core 1 and the inner wall of the coil skeleton 3, a gap will still remain. Figure 3 The design of the core assembly in this embodiment is achieved by optimizing the shape of the ends of the moving and static cores without shortening the length of the moving core 1, thus ensuring that the moving core 1 has good guidance when working.
[0031] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art based on the concepts of the present invention through logical analysis, reasoning, or limited experimentation based on the existing technology should be within the scope of protection defined by the claims.
Claims
1. A core assembly of a DC coil controlled contactor, comprising a matching moving core (1) and a stationary core (2), characterized in that: The longitudinal section of the end of the moving iron core (1) is a convex trapezoid, including an upper end face, a lower end face and a step face, and the longitudinal section of the end of the static iron core (2) is a concave trapezoid, including an opening face and a bottom face.
2. The core assembly of the DC coil controlled contactor according to claim 1, characterized in that: The moving iron core (1) is riveted to the clamping plate and clamped in the clamping slot of the contact support (4), forming an integral structure with the contact support (4).
3. The core assembly of the DC coil controlled contactor according to claim 2, characterized in that: A gap is left between the contact support (4) and the sliding groove (5).
4. The iron core assembly of the DC coil controlled contactor according to claim 1, characterized in that: The static iron core (2) is riveted to the lower base plate of the magnetic yoke.
5. The iron core assembly of the DC coil controlled contactor according to claim 4, characterized in that: A gap is left between the moving iron core (1) and the inner wall of the coil frame (3).
6. The iron core assembly of the DC coil controlled contactor according to claim 5, characterized in that: The coil frame (3) is sleeved on the static iron core (2) and installed in the magnetic yoke.
7. The iron core assembly of the DC coil controlled contactor according to claim 5, characterized in that: When the contactor control circuit is not energized, the movable iron core (1) extends into the coil frame (3) to a length exceeding half of its operating stroke.
8. The iron core assembly of the DC coil controlled contactor according to claim 1, characterized in that: The sum of the outer diameter of the lower end surface of the end of the moving iron core (1) and the maximum dimension of the downward offset of the step surface is smaller than the inner diameter of the opening surface of the end of the static iron core (2).
9. The iron core assembly of the DC coil controlled contactor according to claim 1, characterized in that: The sum of the outer diameter of the upper end surface of the end of the moving iron core (1) and the maximum dimension of the upper end surface offset downward is smaller than the inner diameter of the bottom surface of the end of the static iron core (2).
10. The iron core assembly of the DC coil controlled contactor according to claim 1, characterized in that: The height of the protruding trapezoid at the end of the moving iron core (1) is greater than or equal to the height of the recessed trapezoid at the end of the static iron core (2).