Hydraulic valve and its magnetic core tube

Abstract

The application provides a magnetic core tube and a hydraulic valve with the same. The magnetic core tube comprises a cylindrical sleeve, a push rod and an armature axially slidably arranged in the sleeve. The sleeve comprises a push rod cavity for accommodating the push rod, an execution cavity communicated with one end of the push rod cavity, and an armature cavity communicated with the other end of the push rod cavity and accommodating the armature. The armature cavity has a stop surface facing away from the push rod cavity. The armature has a front end surface facing the stop surface and an oil passage eccentrically and axially penetrating the armature. The armature has a front limit position close to the stop surface. The magnetic core tube comprises a protrusion integrally arranged on the stop surface, the front end surface or the push rod, so that the front end surface and the stop surface maintain a gap at the front limit position. The push rod cavity and the oil passage maintain communication at the front limit position.

Description

Technical Field

[0001] This application belongs to the field of electromagnetic technology, specifically relating to a magnetic core tube. Background Technology

[0002] Please refer to the magnetic core tube shown in Chinese Utility Model Patent No. CN208903772U, which has an appendix. Figure 1 The patent discloses a commonly used design detail in the industry: a magnetic shield (a black ring, not labeled in the patent drawings) is placed on the front stop surface of the iron tongue receiving cavity inside the guide sleeve. This prevents excessive force from being generated when the iron tongue moves to the leftmost stop position of the guide sleeve, which could cause the magnetic core tube to malfunction. However, this design requires additional components and increases the overall product risk due to the increased installation steps.

[0003] Therefore, it is necessary to improve upon existing technologies to overcome the technical problems present in the prior art. Summary of the Invention

[0004] The main problem this application aims to solve is the increased number of components and the complexity of the manufacturing process caused by the installation of magnetic shielding sheets in the magnetic core tube.

[0005] To solve the above-mentioned technical problems, this application provides a magnetic core tube, including a cylindrical sleeve and a push rod and an armature slidably assembled in the sleeve. The sleeve includes a push rod cavity for receiving the push rod, an execution cavity communicating with one end of the push rod cavity, and an armature cavity communicating with the other end of the push rod cavity and receiving the armature. The armature cavity has a stop surface facing away from the push rod cavity. The armature has a front end face facing the stop surface and an eccentric oil passage axially penetrating the armature. The armature has a front limit position close to the stop surface. The magnetic core tube includes a protrusion integrally disposed on the stop surface, the front end face, or the push rod to maintain a gap between the front end face and the stop surface at the front limit position. The push rod cavity and the oil passage remain connected at the front limit position.

[0006] Furthermore, the push rod and the armature are separately disposed, and the protrusion is disposed on the front end surface and contacts the push rod.

[0007] Furthermore, the protrusion has a protrusion contact plane parallel to the stop surface, and the push rod has a push rod contact plane abutting against the protrusion contact plane, the protrusion contact plane covering at least 3 / 4 of the outer periphery of the push rod contact plane.

[0008] Furthermore, the protrusion has a plane, curved surface, or arc surface that contacts the stop surface.

[0009] Furthermore, both the protrusion and the armature are cylindrical in shape, and the diameter ratio of the protrusion and the armature is not less than 1 / 5 and not greater than 3 / 4.

[0010] Furthermore, the protrusion, armature, and push rod are coaxial, and the diameter of the protrusion is larger than the diameter of the push rod cavity.

[0011] Furthermore, the protrusion is provided with a clearance notch to keep the push rod cavity and the oil passage connected.

[0012] Furthermore, the gap between the front end face and the stop face at the front limit position is between 0.1 mm and 1 mm.

[0013] Furthermore, the end of the armature cavity away from the push rod cavity is provided with an opening, and the magnetic core tube has an end cap assembled into the opening and defining the rear limit position of the armature.

[0014] This application also provides a hydraulic valve, which includes a valve body, an electromagnetic coil, and the magnetic core tube.

[0015] This application integrates a protrusion on the stop surface, front end surface, or push rod front end surface to maintain a gap between the front end surface and the stop surface at the front limit position and to maintain communication between the push rod cavity and the oil passage. Without the need for a separate magnetic isolation and demagnetization component, it can reduce or adjust the attraction force of the armature and ensure the working performance of the magnetic core tube. Attached Figure Description

[0016] This application will be more fully understood by referring to the following detailed description of specific embodiments in conjunction with the accompanying drawings. Wherein: Figure 1 This paper shows a cross-sectional view of the magnetic core tube of this application. Figure 2 Showing a partial enlarged view of the contact area between the push rod and the armature, wherein the armature is located at the front limit position; Figure 3 This application shows a three-dimensional structural schematic diagram of the armature. Figure 4 show Figure 3 Left view of the armature, with dashed lines showing the axial projection of the push rod. Detailed Implementation

[0017] The following describes in detail, with reference to the accompanying drawings, a specific embodiment of a magnetic core tube and a hydraulic valve having said magnetic core tube.

[0018] Please see Figures 1 to 4The magnetic core tube includes a cylindrical sleeve 10 and a push rod 20 and an armature 30 axially slidably mounted on the sleeve 10. The sleeve 10 includes a push rod cavity 101 that houses the push rod 20, an execution cavity 102 communicating with one end of the push rod cavity 101, and an armature cavity 103 communicating with the other end of the push rod cavity 101 and housing the armature 30. During operation, an electromagnetic coil (not shown) is assembled on the outer periphery of the sleeve 10 corresponding to the armature cavity 103, attracting the armature 30 to move towards the push rod cavity 101, thereby driving the push rod 20 in the magnetic core tube to move, and then transmitting the movement outward from the end of the push rod 20 in the execution cavity 102. The embodiments described in this application are mainly applied to hydraulic valves, where the end of the push rod 20 is assembled to the valve body of the hydraulic valve and drives the valve core within the valve body to move, thereby switching between different hydraulic passages to realize the function of the hydraulic valve.

[0019] The armature cavity 103 has a stop surface 1031 facing away from the push rod cavity 101. The armature 30 has a front end face 301 facing the stop surface 1031 and an eccentric oil passage 302 that axially penetrates the armature 30. The armature 30 has a front limit position near the stop surface 1031. The magnetic core tube includes a protrusion 40 integrally disposed on the front end face 301 to maintain a gap between the front end face 301 and the stop surface 1031 at the front limit position. The push rod cavity 101 and the oil passage 302 remain connected at the front limit position. The hydraulic oil enters the armature cavity 103 from the actuator cavity 102, through the gap between the push rod 20 and the push rod cavity 101, while the oil passage 302 ensures the flow and pressure balance of the liquid on the left and right sides when the armature 30 reciprocates within the armature cavity 103. This application integrates a protrusion 40 onto the front end face 301 to maintain a gap between the front end face 301 and the stop face 1031 at the front limit position, and to maintain communication between the push rod cavity 101 and the oil passage 302. This allows for the reduction or adjustment of the armature 30's attraction force without the need for a separate magnetic isolation / demagnetization component, thus ensuring the working performance of the magnetic core tube. It is important to emphasize that the integrally integrated protrusion 40 mentioned here is formed using the material of the part itself and does not include cases where it is assembled, bonded, or welded together. The protrusion 40 is located on the front end face 301 and contacts the push rod 20, facilitating manufacturing. Please refer to [further details needed]. Figure 4 The protrusion 40 has a protrusion contact plane parallel to the stop surface 1031, and the push rod 20 has a push rod contact plane abutting against the protrusion contact plane. The protrusion contact plane covers at least 3 / 4 of the outer periphery of the push rod contact plane. Specifically, in this embodiment, viewed from the axial projection, Figure 4The design that the central convex portion 40 (convex contact plane) covers at least 3 / 4 of the outer periphery of the push rod 20 (push rod contact plane) shown by the dashed line can ensure that the push rod 20 can receive the external force from the armature 30 in a relatively balanced manner, and reduce the impact on the structure and lifespan of the push rod 20 and the push rod cavity 101 caused by the radial component force when the convex portion 40 impacts the push rod 20. Figure 4 The portion of the push rod 20 that overlaps with the oil passage 302 is the part of the push rod 20 that is not abutted by the protrusion 20. In this embodiment, the protrusion 40, armature 30, and push rod 20 are coaxial, and the diameter D1 of the protrusion 40 is larger than the diameter D3 of the push rod cavity 101. Therefore, it can basically ensure that the protrusion 40 covers at least 3 / 4 of the outer circumference of the push rod 20. In other embodiments, especially in embodiments where the protrusion 20 and armature 30 are not coaxial, this constraint is particularly important. It should be noted that the condition of covering at least 3 / 4 of the outer circumference does not require the cross-section of the push rod to be circular. It can also be a regular hexagon or other shapes, as long as at least 270 degrees of the outer circumference on the 360-degree circumference is in contact and covered.

[0020] Please continue to refer to the appendix. Figure 1-4 Both the protrusion 40 and the armature 30 are generally cylindrical, and the diameter ratio (D1 / D2) of the protrusion 40 and the armature 30 is not less than 1 / 5 and not greater than 3 / 4. The cylindrical protrusion 40 can better withstand the force during impact, and the constrained diameter ratio of the two can better achieve force balance at the previous limit position. The coaxial design and diameter ratio allow the protrusion 40 to be located in the center of the armature 30, while the gap is formed around the protrusion 40, creating an oil ring filled with hydraulic oil, thereby achieving a more favorable magnetic force distribution. Please refer to [further details]. Figure 3 and Figure 4 The protrusion 40 is provided with a clearance notch to maintain communication between the push rod cavity 101 and the oil passage 302. Specifically, in this embodiment, from the axial projection, the push rod cavity 101 and the oil passage 302 overlap, and the clearance notch is the part removed due to interference between the protrusion 40 and the through oil passage 302 (as mentioned earlier, the protrusion 40 is generally cylindrical, and the existence of this clearance notch makes the cylindrical structure of the protrusion 40 appear incomplete). The gap L maintained between the front end face 301 and the stop face 1031 at the front limit position is between 0.1 mm and 1 mm. The diameter ratio of the protrusion 40 and the armature 30 mentioned above, as well as the gap control mentioned here, effectively guarantee the technical solution of this application. The end of the armature cavity 103 away from the push rod cavity 101 is provided with an opening, and the magnetic core tube has an end cap 50 assembled in the opening and defining the rear limit position of the armature 30. The end cap 50 ensures the sealing of the opening on the one hand, and limits the rear limit position of the armature 30 on the other hand, ensuring the normal operation of the magnetic core tube.

[0021] The above specific embodiments are only used to illustrate this application and are not intended to limit this application. For example, in this embodiment, the protrusion is integrally disposed on the armature. In other embodiments, the protrusion may also be disposed on the stop surface, or even at the end of the push rod (the part that contacts the front end face of the armature), as long as it can be integrally disposed on an existing component and spaced apart from the front end face and the stop surface. Furthermore, in this embodiment, the push rod and the armature are separately disposed. In other embodiments, the push rod and the armature may also be fixedly connected as one piece. Moreover, in this embodiment, the protrusion has a plane (parallel to the stop surface) that contacts the stop surface. In other embodiments, the protrusion may also be a curved surface or an arc surface, as long as it helps to form a gap at the front limit position and ensures the communication between the push rod cavity and the oil passage. In summary, those skilled in the art can make various changes and modifications without departing from the scope of this application. Therefore, all equivalent technical solutions also fall within the scope of this application, and the patent protection scope of this application should be defined by the claims.

Claims

1. A magnetic core tube, comprising a cylindrical sleeve (10) and a push rod (20) and an armature (30) axially slidably disposed in the sleeve (10), the sleeve (10) comprising a push rod cavity (101) for receiving the push rod (20), an execution cavity (102) communicating with one end of the push rod cavity (101), and an armature cavity (103) communicating with the other end of the push rod cavity (101) and receiving the armature (30), the armature cavity (103) having a stop surface (1031) facing away from the push rod cavity (101), the armature (30) having a front end face (301) facing the stop surface (1031) and an eccentric oil passage (302) axially penetrating the armature (30), characterized in that: The armature (30) has a front limit position close to the stop surface (1031). The magnetic core tube includes a protrusion (40) integrally disposed on the stop surface (1031), the front end face (301), or the push rod (20) to keep the front end face (301) and the stop surface (1031) at the front limit position. The push rod cavity (101) and the oil passage (302) are connected at the front limit position. The protrusion (40) and the armature (30) are generally cylindrical. The diameter ratio of the protrusion (40) and the armature (30) is not less than 1 / 5 and not greater than 3 / 4. The protrusion (40), the armature (30), and the push rod (20) are coaxial. The diameter of the protrusion (40) is greater than the diameter of the push rod cavity (101), so that a gap is formed around the protrusion (40) and an oil ring filled with hydraulic oil is formed.

2. The magnetic core tube as described in claim 1, characterized in that, The push rod (20) and armature (30) are separated, and the protrusion (40) is disposed on the front end face (301) and contacts the push rod (20).

3. The magnetic core tube as described in claim 2, characterized in that, The protrusion (40) has a protrusion contact plane parallel to the stop surface (1031), and the push rod (20) has a push rod contact plane abutting against the protrusion contact plane, the protrusion contact plane covering at least 3 / 4 of the outer periphery of the push rod contact plane.

4. The magnetic core tube as described in claim 2, characterized in that, The protrusion (40) has a plane, curved surface or arc surface that contacts the stop surface (1031).

5. The magnetic core tube as described in claim 2, characterized in that, The protrusion (40) is provided with a clearance notch to keep the push rod cavity (101) and the oil passage (302) connected.

6. The magnetic core tube as described in any one of claims 1-5, characterized in that, The gap between the front end face (301) and the stop face (1031) at the front limit position is between 0.1 mm and 1 mm.

7. The magnetic core tube as described in claim 6, characterized in that, The armature cavity (103) has an opening at one end away from the push rod cavity (101), and the magnetic core tube has an end cap (50) assembled into the opening and defining the rear extreme position of the armature (30).

8. A hydraulic valve, characterized in that: It includes a valve body, an electromagnetic coil, and a magnetic core tube having any one of claims 1-7.

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