A linear motor magnetic steel assembly

Abstract

The present invention provides a linear motor magnetic steel assembly, the magnetic steel assembly includes a magnetic steel, a magnetic steel frame, a first mover yoke and a second mover yoke, wherein the magnetic steel, the first mover yoke and the second mover yoke are all sleeved outside the magnetic steel frame, the first mover yoke and the second mover yoke are respectively located on both sides of the magnetic steel, the inner hole of the first mover yoke has an internal thread, and an external thread is provided at a position of the magnetic steel frame corresponding to the first mover yoke, and the internal thread of the first mover yoke is connected to the external thread of the magnetic steel frame. A glue storage tank is provided at the connection between the second mover yoke and the magnetic steel frame, and a glue bond is formed after the medium-temperature epoxy structural glue in the glue storage tank is cured to prevent the second mover yoke from falling off the magnetic steel frame. The first mover yoke and the magnetic steel frame are fixedly connected by thread + medium-temperature epoxy structural glue, which greatly improves the reliability of the magnetic steel assembly.

Description

Technical Field

[0001] The invention relates to the field of moving magnet linear motors for Stirling refrigerators, and in particular to a magnetic steel assembly of a linear motor. Background Art

[0002] The moving magnet linear motor for Stirling refrigerator is used to drive the piston in the linear compressor of Stirling refrigerator. The magnetic steel assembly in the linear motor consists of three parts: magnetic steel frame, magnetic steel and moving yoke. After the magnetic steel assembly is connected to the piston, it performs linear reciprocating motion in the whole machine.

[0003] In the prior art, the magnetic steel assembly uses medium-temperature epoxy structural adhesive to bond the mover yoke, magnetic steel and magnetic steel frame, and welds the joints between the mover yoke and the magnetic steel frame to ensure that the magnetic steel on the magnetic steel assembly does not fall off. Since the mover yoke is made of industrial pure iron and the magnetic steel frame is made of stainless steel, the two different materials of the mover yoke and the magnetic steel frame cause cracks in the laser welding. The magnetic steel can only be prevented from falling off by local deformation of the mover yoke and the magnetic steel frame, and it cannot reliably prevent the magnetic steel assembly from loosening and causing abnormal noise during the operation of the whole machine.

[0004] In order to solve the above problems, a linear motor magnetic steel assembly is needed. Summary of the invention

[0005] The object of the present invention is to provide a linear motor magnetic steel assembly, which can firmly connect the first mover yoke, the second mover yoke, the magnetic steel and the magnetic steel frame without welding, thereby greatly improving the reliability of the magnetic steel assembly.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A linear motor magnetic steel assembly, the magnetic steel assembly comprising a magnetic steel, a magnetic steel frame, a first movable yoke and a second movable yoke, wherein the magnetic steel, the first movable yoke and the second movable yoke are all sleeved on the outside of the magnetic steel frame, the first movable yoke and the second movable yoke are respectively located on both sides of the magnetic steel, the inner hole of the first movable yoke has an internal thread, and an external thread is provided at a position of the magnetic steel frame corresponding to the first movable yoke, and the internal thread of the first movable yoke is connected to the external thread of the magnetic steel frame.

[0008] Furthermore, in the above-mentioned linear motor magnetic steel assembly, a first groove is provided at the end of the inner hole of the second mover yoke.

[0009] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the first groove is arranged at an end of the second mover magnetic yoke close to the magnetic steel.

[0010] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the magnetic steel skeleton is provided with a second groove.

[0011] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the second groove corresponds to the position of the first groove, and the first groove and the second groove together form a glue storage groove, which is used to accommodate medium-temperature curing epoxy structural glue.

[0012] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the inner hole of the first mover yoke and the inner hole of the magnetic steel are both bonded to the magnetic steel skeleton through medium-temperature curing epoxy structural adhesive, the second mover yoke is bonded to the magnetic steel skeleton through the medium-temperature curing epoxy structural adhesive in the adhesive storage tank, and the two end surfaces of the magnetic steel are respectively bonded to the first mover yoke and the second mover yoke through the medium-temperature curing epoxy structural adhesive; a boss is provided on the magnetic steel skeleton on the outside of the second mover yoke, and the end surface of the second mover yoke is in contact with the end surface of the boss.

[0013] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the first mover yoke and the second mover yoke are made of industrial pure iron, the left end of the external thread of the magnetic steel skeleton is 0.5 mm away from the axial leftmost end of the inner hole of the first mover yoke, and the right end of the external thread of the magnetic steel skeleton penetrates into the inner hole of the magnetic steel by 0.5 mm to 1 mm, and the specification of the external thread is MD2×0.5.

[0014] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the second groove is an annular groove, and the axial depth of the second groove is 0.3 mm and the radial depth is 0.2 mm.

[0015] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the axial length of the internal thread of the first mover yoke is 1.5 mm, and the specification of the internal thread is MD2×0.5.

[0016] Furthermore, in the above-mentioned linear motor magnetic steel assembly, the first groove is an annular groove, and the axial depth and radial depth of the first groove are both 0.3 mm.

[0017] It can be seen from the analysis that the present invention discloses a linear motor magnetic steel assembly, wherein a glue storage tank is provided at the connection between the second mover magnetic yoke and the magnetic steel frame, and medium-temperature epoxy structural glue is applied in the glue storage tank and at the connection between the second mover magnetic yoke, the magnetic steel frame and the magnetic steel. After the medium-temperature epoxy structural glue is cured, a glue bond is formed to prevent the second mover magnetic yoke from falling off the magnetic steel frame. The first mover magnetic yoke and the magnetic steel frame are fixedly connected by thread + medium-temperature epoxy structural glue. After the first mover magnetic yoke is tightened, the magnetic steel and the second mover magnetic yoke can be locked to prevent the magnetic steel, the first mover magnetic yoke and the second mover magnetic yoke from falling off, so that the first mover magnetic yoke, the second mover magnetic yoke, the magnetic steel and the magnetic steel frame are firmly connected, which greatly improves the reliability of the magnetic steel assembly. After the medium-temperature epoxy structural glue is cured, it can prevent the thread of the first mover magnetic yoke from loosening. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0019] Figure 1 It is a structural schematic diagram of an embodiment of the present invention.

[0020] Figure 2 Schematic diagram of the structure of a magnetic steel skeleton according to an embodiment of the present invention.

[0021] Figure 3 It is a schematic structural diagram of a first movable yoke according to an embodiment of the present invention.

[0022] Figure 4 Schematic diagram of the structure of the second movable yoke according to an embodiment of the present invention.

[0023] Figure 5 for Figure 1 Schematic diagram of the enlarged structure at point A in the middle.

[0024] Explanation of the reference numerals: 1, magnetic steel skeleton; 101, external thread; 102, second groove; 103, boss; 2, first mover yoke; 201, internal thread; 3, magnetic steel; 4, second mover yoke; 401, first groove; 5, glue storage tank. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention and does not limit the present invention. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as a part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present invention encompasses such modifications and variations within the scope of the appended claims and their equivalents.

[0026] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected", "connected" and "set" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component; it can be a wired electrical connection, a radio connection, or a wireless communication signal connection. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0027] One or more examples of the present invention are shown in the accompanying drawings. The detailed description uses numbers and letter labels to refer to features in the drawings. Like or similar labels in the drawings and description have been used to refer to like or similar parts of the present invention. As used herein, the terms "first", "second", "third", etc. are used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of individual components.

[0028] like Figures 1 to 4 As shown, according to an embodiment of the present invention, a linear motor magnetic steel assembly is provided, such as Figure 1 As shown, the magnetic steel assembly includes a magnetic steel 3, a magnetic steel frame 1, a first mover yoke 2 and a second mover yoke 4 (in Figure 1 In the embodiment, the first mover yoke 2 is a left yoke, and the first mover yoke 2 is located on the left side of the magnetic steel 3, and the second mover yoke 4 is a right yoke, and the second mover yoke 4 is located on the right side of the magnetic steel 3), wherein the magnetic steel skeleton 1 is a cylindrical structure, and the magnetic steel 3, the first mover yoke 2 and the second mover yoke 4 are all provided with inner holes, and the magnetic steel 3, the first mover yoke 2 and the second mover yoke 4 are all sleeved on the outside of the magnetic steel skeleton 1 through their inner holes, and the first mover yoke 2 and the second mover yoke 4 are respectively located on both sides of the magnetic steel 3, such as Figure 3 As shown, the inner hole of the first mover yoke 2 has an internal thread 201, and an external thread 101 is provided at a position of the magnetic steel frame 1 corresponding to the first mover yoke 2, and the internal thread 201 of the first mover yoke 2 is connected to the external thread 101 of the magnetic steel frame 1; Figure 2 As shown, a boss 103 is provided on the magnetic steel frame 1 outside the second movable magnetic yoke 4, and the outer surface (right end face) of the second movable magnetic yoke 4 contacts the end face of the boss 103. After tightening the first movable magnetic yoke 2, the first movable magnetic yoke 2 cooperates with the boss 103 to lock the magnetic steel 3 and the second movable magnetic yoke 4 so that they cannot move, effectively preventing the loosening of the magnetic steel assembly and improving the reliability of the magnetic steel assembly.

[0029] Furthermore, the inner hole of the first mover yoke 2 and the inner hole of the magnetic steel 3 are both bonded to the magnetic steel skeleton 1 through medium-temperature curing epoxy structural glue, and the second mover yoke 4 is bonded to the magnetic steel skeleton 1 through the medium-temperature curing epoxy structural glue in the glue storage tank 5. The inner hole surface of the second mover yoke 4 is not coated with glue in order to reduce the excess glue at the joint between the second mover yoke 4 and the boss 103. The two end surfaces of the magnetic steel 3 are respectively bonded to the first mover yoke 2 and the second mover yoke 4 through medium-temperature curing epoxy structural glue. After the magnetic steel assembly is assembled, it is placed in an oven as a whole for heating and curing. After the medium-temperature curing epoxy structural glue is cured, the connection between the first mover yoke 2, the magnetic steel 3, the second mover yoke 4 and the magnetic steel skeleton 1 can be firmly connected, and the thread between the first mover yoke 2 and the magnetic steel skeleton 1 can also be prevented from loosening, further improving the reliability of the magnetic steel assembly.

[0030] Further, as shown in Figure 4, a first groove 401 is provided at the end of the inner hole of the second mover yoke 4. The first groove 401 is provided at one end of the second mover yoke 4 close to the magnetic steel 3. The first groove 401 is provided in an annular shape, and the first groove 401 surrounds the inner wall of the inner hole of the second mover yoke 4. One end of the inner hole of the second mover yoke 4 close to the magnetic steel 3 is recessed into the second mover yoke 4 to form the first groove 401. The first groove 401 is used to accommodate the medium-temperature curing epoxy structural glue, so that the second mover yoke 4 and the magnetic steel skeleton 1 are firmly connected.

[0031] Furthermore, if Figure 2 As shown, the magnetic steel frame 1 is provided with a second groove 102. The second groove 102 is an annular groove, and the second groove 102 surrounds the outer wall of the magnetic steel frame 1, and the position of the second groove 102 corresponds to that of the first groove 401. Figure 1 and Figure 5 As shown, the first groove 401 and the second groove 102 together form a glue storage tank 5, and the glue storage tank 5 is used to accommodate medium-temperature curing epoxy structural glue. The setting of the glue storage tank 5 can allow the connection between the second mover yoke 4 and the magnetic steel frame 1 to accommodate more medium-temperature curing epoxy structural glue. After the medium-temperature epoxy structural glue in the glue storage tank 5 is cured, a glue bond is formed to prevent the second mover yoke 4 from falling off the magnetic steel frame 1, so that the connection between the second mover yoke 4 and the magnetic steel frame 1 is more firm, and the reliability of the magnetic steel assembly is further improved.

[0032] Furthermore, the first mover yoke 2 and the second mover yoke 4 are made of industrial pure iron, which is a kind of steel, and its chemical composition is mainly iron, with a total impurity content of <0.2% and a carbon content of 0.02% to 0.04%. Pure iron with a carbon content not exceeding 0.0218% is also called ingot iron. Figure 2As shown, the left end of the external thread 101 of the magnetic steel frame 1 is 0.5mm away from the leftmost end of the inner hole of the first movable yoke 2 in the axial direction, and the right end of the external thread 101 of the magnetic steel frame 1 is 0.5mm to 1mm deep into the inner hole of the magnetic steel 3. The length between the external thread 101 of the magnetic steel frame 1 and one end of the magnetic steel frame 1 (the end not connected to the magnetic steel 3) is L1. Because the residual glue in the thread is difficult to clean, and in order to ensure strength, L1 ensures that the left end of the thread slightly exceeds the installation surface of the first movable yoke 2 (0.5mm). The length between the right end of the external thread 101 of the magnetic steel skeleton 1 and one end of the boss 103 (the end connected to the magnetic steel 3) is L2, and L2 is slightly smaller than the sum of the axial length of the inner hole (mounting surface) of the second movable yoke 4 and the axial length of the inner hole (mounting surface) of the magnetic steel 3. Slightly smaller means 0.5mm~1mm smaller, ensuring that the right end of the external thread 101 of the magnetic steel skeleton 1 penetrates into the inner hole of the magnetic steel 3 by 0.5mm~1mm, ensuring that the first movable yoke 2 can lock the magnetic steel 3 and the second movable yoke 4.

[0033] The outer diameter of the connection between the magnetic steel frame 1, the magnetic steel 3 and the second movable yoke 4 is D2, and D2 is determined according to the size of the magnetic steel frame 1. The axial length of the external thread 101 is 1mm to 1.5mm longer than the axial length of the inner hole of the first movable yoke 2, and the specification of the external thread 101 is MD2×0.5 (the thread is determined according to the size of the magnetic steel frame D2, for example, if D2 is 22, the specification of the external thread 101 is M22×0.5). The outer diameter D1 of the magnetic steel frame 1 between one end of the magnetic steel frame 1 and the external thread 101 is slightly smaller than the thread bottom diameter of the external thread 101 (0.1mm smaller), which is convenient for the installation of the first movable yoke 2. The axial length of the internal thread 201 of the first movable yoke 2 is 1.5mm, and the specification of the internal thread 201 is MD2×0.5 (the thread is determined according to the size of the magnetic steel frame D2, for example, if D2 is 22, the specification of the internal thread 201 is M22×0.5). The setting of the above parameters can ensure a firm connection between the first mover yoke 2, the second mover yoke 4, the magnetic steel 3 and the magnetic steel frame 1, and maintain a small amount of residual glue inside the magnetic steel assembly, thereby improving the reliability of the magnetic steel assembly.

[0034] Furthermore, if Figure 2 As shown, the second groove 102 is an annular groove, and the axial depth of the second groove 102 is 0.3mm and the radial depth is 0.2mm. The first groove 401 is an annular groove, and the axial depth and radial depth of the first groove 401 are both 0.3mm. After the medium-temperature epoxy structural glue in the glue storage tank 5 is cured, a glue bond is formed to prevent the second mover yoke 4 from falling off the magnetic steel frame 1, ensuring that the second mover yoke 4 and the magnetic steel frame 1 are firmly connected.

[0035] During the installation of the magnetic steel assembly, the second movable yoke 4 is firstly sleeved on the magnetic steel skeleton 1 through its inner hole, the right end face of the second movable yoke 4 contacts the end face of the boss 103, the first groove 401 of the second movable yoke 4 is aligned with the second groove 102 of the magnetic steel skeleton 1 to form a glue storage tank 5, a circle of medium-temperature epoxy structural glue is applied on the contact outer cylindrical surface of the magnetic steel skeleton 1 and the magnetic steel 3, and then the magnetic steel 3 is pressed into the magnetic steel skeleton 1 through its inner hole, and the medium-temperature curing glue on the outer cylindrical surface of the magnetic steel skeleton 1 is pushed into the glue storage tank 5 and the right end face of the magnetic steel 3 and the left end face of the second movable yoke 4. The glue storage tank 5 also has the function of reducing the overflow of excess medium-temperature curing structural glue from the joint between the right end face of the second movable yoke and the boss 103. Finally, apply a small amount of medium-temperature epoxy structural glue on the external thread 101 of the magnetic steel frame 1, screw the first mover yoke 2 into the magnetic steel frame 1 and tighten it. Wipe off the remaining glue at each joint with alcohol and put it in an oven for heating and curing.

[0036] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0037] A linear motor magnetic steel assembly, the magnetic steel assembly includes a magnetic steel 3, a magnetic steel frame 1, a first movable yoke 2 and a second movable yoke 4, a glue storage tank 5 is provided at the connection between the second movable yoke 4 and the magnetic steel frame 1, and medium-temperature epoxy structural glue is applied in the glue storage tank 5 and at the connection between the cylindrical surface of the magnetic steel frame 1 and the magnetic steel 3. After the medium-temperature epoxy structural glue in the glue storage tank 5 is cured, a glue bond is formed to prevent the second movable yoke 4 from falling off from the magnetic steel frame 1. The first movable yoke 2 and the magnetic steel frame 1 are fixedly connected by thread + medium-temperature epoxy structural glue. After the first movable yoke 2 is tightened, the magnetic steel 3 and the second movable yoke 4 can be locked to prevent the magnetic steel 3, the first movable yoke 2 and the second movable yoke 4 from falling off, so that the first movable yoke 2, the second movable yoke 4, the magnetic steel 3 and the magnetic steel frame 1 are firmly connected, and the reliability of the magnetic steel assembly is greatly improved. After the medium-temperature epoxy structural glue is cured, it can prevent the thread of the first movable yoke 2 from loosening.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A linear motor magnetic steel assembly, characterized in that: The magnetic steel assembly includes a magnetic steel, a magnetic steel frame, a first mover yoke and a second mover yoke, wherein: The magnetic steel, the first mover yoke and the second mover yoke are all sleeved outside the magnetic steel frame. The first mover yoke and the second mover yoke are respectively located on two sides of the magnetic steel. The inner hole of the first mover yoke has an internal thread, An external thread is provided at a position of the magnetic steel frame corresponding to the first mover yoke. The internal thread of the first mover yoke is connected to the external thread of the magnetic steel frame. The end of the inner hole of the second mover magnetic yoke is provided with a first groove, the magnetic steel skeleton is provided with a second groove, the second groove corresponds to the position of the first groove, the first groove and the second groove together form a glue storage tank, and the glue storage tank is used to contain medium temperature curing epoxy structural glue, The inner hole of the first mover yoke and the inner hole of the magnetic steel are both bonded to the magnetic steel frame by medium-temperature curing epoxy structural adhesive, and the inner hole of the second mover yoke is bonded to the magnetic steel frame by medium-temperature curing epoxy structural adhesive in the adhesive storage tank. The two end surfaces of the magnetic steel are respectively bonded to the first mover yoke and the second mover yoke by medium-temperature curing epoxy structural adhesive; A boss is arranged on the magnetic steel frame outside the second mover yoke, and an end surface of the second mover yoke contacts an end surface of the boss.

2. The linear motor magnetic steel assembly according to claim 1, characterized in that: The first groove is arranged at an end of the second mover yoke close to the magnetic steel.

3. The linear motor magnetic steel assembly according to claim 1, characterized in that: The first mover yoke and the second mover yoke are made of industrial pure iron. The left end of the external thread of the magnetic steel frame is 0.5 mm away from the leftmost end of the inner hole of the first mover yoke, and the right end of the external thread of the magnetic steel frame is 0.5 mm to 1 mm deep into the inner hole of the magnetic steel. The specification of the external thread is MD2×0.

5.

4. The linear motor magnetic steel assembly according to claim 1, characterized in that: The second groove is an annular groove, and the axial depth of the second groove is 0.3 mm and the radial depth of the second groove is 0.2 mm.

5. The linear motor magnetic steel assembly according to claim 1, characterized in that: The axial length of the internal thread of the first mover yoke is 1.5 mm, and the specification of the internal thread is MD2×0.

5.

6. The linear motor magnetic steel assembly according to claim 1, characterized in that: The first groove is an annular groove, and the axial depth and radial depth of the first groove are both 0.3 mm.

Images