CN115551271B - Fixing device - Google Patents

Abstract

A fixing device is suitable for a circuit board assembled on a substrate of an electronic device. The circuit board is provided with a combining hole. The fixing device comprises a bearing combined on the base plate, a sleeve surrounding the bearing and a shell combined on the sleeve. The bearing includes a stem. The lever portion has a protruding member. The shell comprises two shells and two elastic clamping pieces. The elastic clamping piece surrounds the protruding piece of the bearing and can be pushed by the protruding piece to clamp the combining hole. The elastic clamping piece can clamp the combining hole of the circuit board and the sleeve can be moved to be linked to enable the elastic clamping piece to be propped against the protruding piece, the elastic clamping piece is clamped and combined with the design of the circuit board, and the design is matched with the design of the bearing to be combined with the substrate, when the elastic clamping piece of the shell is propped against and expanded by the protruding piece of the bearing to clamp the circuit board, the circuit board is assembled and combined with the substrate, and the tool-free assembling operation is convenient and effective to assemble.

Description

Fixing device

Technical Field

The present invention relates to a mounting assembly, and more particularly to a tool-free assembly fixture.

Background

In a server system, a circuit board is usually locked and combined on a bottom board or a main board in a server case, and usually screws or other locking and mounting components are used for mounting and fixing the circuit board. In assembly, besides the need of preparing screw components, users have to use locking tools to lock the circuit board in a troublesome manner, so that the assembly is very time-consuming and labor-consuming and causes trouble for users, and the practitioner is very required to further think and study improvement schemes.

Disclosure of Invention

The invention aims to provide a fixing device which is convenient to install and can be assembled without tools.

In order to solve the technical problems, the fixing device of the invention is suitable for assembling a circuit board on a substrate of an electronic device. The circuit board is provided with a combining hole. The fixing device is arranged on the substrate and extends from the substrate to the direction of the circuit board, and comprises a bearing combined on the substrate, a spring unit combined on the bearing, a sleeve surrounding the bearing and combined on the spring unit, and a shell combined on the sleeve.

The bearing comprises a base part combined on the substrate and a rod part extending from the base part to the direction of the circuit board. The rod part is provided with a rod body and a protruding part extending from the rod body to the direction of the combining hole of the circuit board.

The spring unit comprises a compression spring longitudinally surrounding the rod body sleeved with the bearing and a steel ball spring transversely penetrating through the rod body of the bearing. The steel ball spring is provided with an elastic body penetrating through the rod body and two steel balls which are arranged at two opposite ends of the elastic body, penetrate out of the rod body and are positioned at two opposite sides of the rod body.

The sleeve comprises a cylinder body combined on the steel ball spring of the spring unit, a chute track which is arranged on the inner side of the cylinder body in a surrounding way and can be used for sliding the steel balls of the steel ball spring, a first limit hole which is arranged in the chute track and can be used for the steel balls of the steel ball spring to enter in a removable way, and a second limit hole which is arranged in the chute track and can be used for the steel balls of the steel ball spring to enter in a removable way. The cylinder covers the bearing and can press the compression spring, and the chute track is provided with two first fixing parts positioned at two opposite sides in the cylinder and two second fixing parts positioned at two opposite sides in the cylinder. The first fixing portions are located above the second fixing portions, each first fixing portion is located between the second fixing portions, the first limiting holes are respectively formed in the first fixing portions of the sliding groove track, and the second limiting holes are respectively formed in the second fixing portions of the sliding groove track. The barrel has a top portion that is pierced by the protruding member of the shaft portion of the bearing.

The shell comprises two shells combined on the outer side of the cylinder body of the sleeve, and two elastic clamping pieces which extend from the shells to the direction of the circuit board and can be removed to clamp the combining holes of the circuit board. The elastic clamping piece surrounds the protruding piece of the bearing and can be pushed by the protruding piece to clamp the combining hole. The sleeve is movable relative to the steel ball of the steel ball spring between an engaged position and a disengaged position. When the sleeve is at the combining position, the first limiting hole of the sleeve is clamped by the steel ball of the steel ball spring, the elastic clamping piece of the shell is propped by the protruding piece of the bearing, and the elastic clamping piece is clamped and combined with the combining hole of the circuit board; when the sleeve is at the non-combination position, the second limiting hole of the sleeve is clamped by the steel ball of the steel ball spring, and the elastic clamping piece of the shell is not propped by the protruding piece of the bearing. When the circuit board is moved towards the direction of the substrate and the combination hole of the circuit board is penetrated by the elastic clamping piece of the shell and the circuit board is pushed towards the direction of the substrate to push the shell of the shell, the shell drives the cylinder body of the sleeve to push the compression spring of the spring unit towards the direction of the substrate and synchronously moves the steel balls of the steel ball spring away from the second limit hole to move along the chute track and towards the first limit hole, the elastic clamping piece of the shell is pushed by the protruding piece of the bearing to expand the elastic clamping pieces towards the direction away from each other, and when the combination position is reached, the steel balls of the steel ball spring are clamped into the first limit hole and the elastic clamping pieces are pushed and expanded by the protruding piece of the bearing to clamp the circuit board, and at the moment, the elastic clamping pieces are clamped and fixedly clamped with the circuit board.

Compared with the prior art, the invention can clamp the combining hole of the circuit board by the elastic clamping piece of the shell and the sleeve can be moved to link the elastic clamping piece of the shell to be propped against the convex piece of the bearing, the design of the elastic clamping piece to clamp the combining hole of the circuit board is combined with the coincidental that the base part of the bearing is combined with the base plate, when the sleeve is moved to the combining position, the steel ball of the steel ball spring is clamped into the first limiting hole of the sleeve, and the elastic clamping piece of the shell is propped against and expanded by the convex piece of the bearing to clamp the circuit board, at the moment, the elastic clamping piece is clamped with the circuit board, so that the circuit board is assembled and combined with the base plate, and the tool-free assembling operation is convenient and effective.

Drawings

Other features and advantages of the present invention will become apparent from the following description of the embodiments with reference to the drawings, in which:

FIG. 1 is an exploded perspective view illustrating an embodiment of the fastening device of the present invention;

FIG. 2 is an exploded view illustrating an embodiment of the fixture of the present invention applied to a circuit board assembly substrate;

FIG. 3 is a cross-sectional view, aided by the illustration of FIG. 2;

FIG. 4 is a perspective view illustrating that in the embodiment, two elastic fasteners of a housing pass through a combining hole of the circuit board;

FIG. 5 is a perspective view illustrating the case in which the elastic clamping member is pushed by a protrusion of a bearing and the elastic clamping member is clamped to the circuit board, and

Fig. 6 is a perspective view illustrating a structure of a chute track of a sleeve in this embodiment.

Detailed Description

Before the present invention is described in detail, it should be noted that in the following description, like components are denoted by the same reference numerals.

Referring to fig. 1, 2,3, 4, 5 and 6, embodiments of the fixing device of the present invention are suitable for assembling a circuit board 80 on a substrate 70 of an electronic device (not shown). The circuit board 80 has a coupling hole 81. The fixing device is disposed on the substrate 70 and extends from the substrate 70 toward the circuit board 80, and comprises a bearing 1 coupled to the substrate 70, a spring unit 2 coupled to the bearing 1, a sleeve 3 surrounding the bearing 1 and coupled to the spring unit 2, and a housing 4 coupled to the sleeve 3.

The bearing 1 includes a base 11 coupled to the base plate 70, and a stem 12 extending from the base 11 toward the circuit board 80. The rod 12 has a rod 121 and a protrusion 122 extending from the rod 121 toward the connecting hole 81 of the circuit board 80. In this embodiment, the base 11 is fixedly coupled to the substrate 70, and has a base 111 coupled to the substrate 70, and a locking member 112 extending from the base 111 toward the substrate 70 and penetrating the substrate 70, and fixedly coupled to the substrate 70.

The spring unit 2 includes a compression spring 21 longitudinally surrounding the rod body 121 sleeved with the bearing 1, and a steel ball spring 22 transversely penetrating the rod body 121 of the bearing 1. The ball spring 22 has an elastic body 221 penetrating the rod 121, and two balls 222 disposed at opposite ends of the elastic body 221 and penetrating the rod 121 and located at opposite sides of the rod 121.

The sleeve 3 includes a cylinder 31 (for convenience of description, the sleeve 3 is divided into two halves in fig. 1 and 6) coupled to the steel ball spring 22 of the spring unit 2, a chute track 32 disposed on the inner side of the cylinder 31 and allowing the steel balls 222 of the steel ball spring 22 to slide, two first limiting holes 33 disposed in the chute track 32 and allowing the steel balls 222 of the steel ball spring 22 to be removably inserted, and two second limiting holes 34 disposed in the chute track 32 and allowing the steel balls 222 of the steel ball spring 22 to be removably inserted. The cylinder 31 covers the bearing 1 and can press the compression spring 21, and the chute track 32 has two first fixing portions 321 located at two opposite sides in the cylinder 31, and two second fixing portions 324 located at two opposite sides in the cylinder 31. The first fixing portions 321 are located above the second fixing portions 324, and each first fixing portion 321 is located between the second fixing portions 324. The first limiting holes 33 are respectively disposed in the first fixing portions 321 of the chute rails 32, and the second limiting holes 34 are respectively disposed in the second fixing portions 324 of the chute rails 32. The barrel 31 has a top 311 which is pierced by the projection 122 of the stem 12 of the bearing 1.

The housing 4 includes two housings 41 coupled to the outer side of the cylinder 31 of the sleeve 3, and two elastic fastening members 42 extending from the housings 41 toward the circuit board 80 and capable of being removed to fasten the coupling holes 81 of the circuit board 80. The elastic clamping member 42 surrounds the protruding member 122 of the bearing 1 and can be pushed by the protruding member 122 to clamp the combining hole 81. The elastic locking member 42 of the housing 4 is tapered from the housing 41 toward the circuit board 80 and surrounds the protruding member 122 of the bearing 1, so that when the protruding member 122 of the bearing 1 is inserted into and pushes against the elastic locking member 42, the tapered portion of the elastic locking member 42 is pushed by the protruding member 122 and expands outwards. In the present embodiment, the shell 41 of the housing 4 is glued and adhered to the outer side of the cylinder 31 of the sleeve 3, but not limited thereto.

The sleeve 3 is movable relative to the steel balls 222 of the steel ball spring 22 between an engaged position and a disengaged position. In the combined position, the first limiting hole 33 of the sleeve 3 is blocked by the steel ball 222 of the steel ball spring 22, the elastic blocking piece 42 of the shell 4 is pushed by the protruding piece 122 of the bearing 1, the elastic blocking piece 42 is blocked and combined with the combining hole 81 of the circuit board 80, and in the non-combined position, the second limiting hole 34 of the sleeve 3 is blocked by the steel ball 222 of the steel ball spring 22, and the elastic blocking piece 42 of the shell 4 is not pushed by the protruding piece 122 of the bearing 1. When the circuit board 80 is moved toward the base plate 70 and the coupling hole 81 of the circuit board 80 is penetrated by the elastic locking member 42 of the housing 4 and the circuit board 80 is pushed toward the base plate 70 to push the housing 41 of the housing 4, the housing 41 drives the cylinder 31 of the sleeve 3 to push the compression spring 21 of the spring unit 2 toward the base plate 70 and simultaneously moves the steel balls 222 of the steel ball spring 22 away from the second limiting hole 34, and then continues to rotate the cylinder 31 of the sleeve 3 toward the base plate 70 and move the steel balls 222 located in the chute track 32 of the sleeve 3 toward the first limiting hole 33, and the elastic locking member 42 of the housing 4 is pushed by the protrusion 122 of the bearing 1 to expand the elastic locking member 42 toward a direction away from each other, and when the coupling position is reached, the steel balls 222 of the spring 22 are locked into the first limiting hole 33 and the protrusion 42 are pushed by the protrusion 122 of the bearing 1 to lock the elastic locking member 80 to lock the circuit board 80. In detail, when an external force is applied to push the housing 41 of the casing 4 against the base plate 70, the housing 41 drives the cylinder 31 of the sleeve 3 to rotate toward the base plate 70 to push the compression spring 21 of the spring unit 2, and the cylinder 31 rotates to simultaneously move the chute track 32 in the cylinder 31 relative to the steel balls 222 and move the steel balls 222 out of the second limit holes 34 in the second fixing portion 324 of the chute track 32, so as to further move the steel balls 222 toward the first limit holes 33 in the first fixing portion 321 of the chute track 32, and when the steel balls 222 are locked into the first limit holes 33 and the elastic locking members 42 of the casing 4 are pushed by the protruding members 122 of the bearing 1, the sleeve 3 is positioned in the combining position and the cylinder 31 of the sleeve 3 is pushed by the protruding members 122 to expand outwards, so that the compression spring 21 of the casing 4 is pushed by the protruding members 122, and the compression spring 1 is accumulated by the compression spring 41 d of the casing 4. In contrast, in the coupling position, since the housing 41 and the base 111 of the bearing 1 are separated by the pre-pressing gap d, the housing 41 of the housing 4 may be pushed against the direction of the base 70, and when an external force is applied to push the housing 41 against the direction of the base 70, the housing 41 may drive the cylinder 31 of the sleeve 3 to move toward the direction of the base 70 to further push the compression spring 21 of the spring unit 2, and the steel balls 222 are moved out of the first limiting hole 33 in the first fixing portion 321 of the sliding groove track 32, and then no external force is applied to push the housing 41 against the direction of the base 70, at this time, the elastic restoring force of the compression spring 21 may push the cylinder 31 away from the direction of the base 70, and the cylinder 31 of the sleeve 3 may rotate away from the direction of the base 70, and in the course of rotation of the cylinder 31, the sliding groove track 32 located in the cylinder 31 may move relative to the steel balls 222 and the steel balls 222 are moved toward the second limiting hole 34 located in the sliding groove track 32, and the second limiting hole 34 located in the second fixing portion 324 of the sliding groove track 32 is not pushed against the second limiting hole 122 of the sleeve 3, and the elastic restoring force of the sleeve 3 is not pushed into the second limiting hole 34 located in the second fixing portion 4 of the sliding groove track 32.

When assembling, after the connection hole 81 of the circuit board 80 is penetrated by the elastic clamping piece 42 of the shell 41, the circuit board 80 is moved towards the direction of the substrate 70 and pushes against the shell 41 of the shell 4, the shell 41 drives the cylinder 31 of the sleeve 3 to move towards the direction of the substrate 70 and push against the compression spring 21 of the spring unit 2, simultaneously the steel balls 222 of the steel ball spring 22 are moved away from the second limiting hole 34 and move towards the first limiting hole 33, the elastic clamping piece 42 of the shell 4 is pushed against by the protruding piece 122 of the bearing 1 and expand the elastic clamping piece 42 towards a direction away from each other, and when moving to the connection position, the steel balls 222 of the steel ball spring 22 are pushed against and expanded by the protruding piece 122 of the bearing 1 and block the circuit board 80, at this time, the elastic clamping piece 42 is clamped on the circuit board 80. Conversely, when the circuit board 80 is to be detached, since the housing 41 is separated from the base 111 of the bearing 1 by the pre-pressing gap d, the housing 41 will drive the barrel 31 of the sleeve 3 to further press the compression spring 21 of the spring unit 2 toward the base 70, and the steel balls 222 will be moved out of the first limiting hole 33 in the first fixing portion 321 of the sliding groove track 32, and then no force is applied to press the circuit board 80 against the housing 41, at this time, the elastic restoring force of the compression spring 21 will push the barrel 31 in a direction away from the base 70, and the barrel 31 will be rotated in a direction away from the base 70, and during the rotation of the barrel 31, the sliding groove track 32 in the barrel 31 will be simultaneously moved relative to the steel balls 222, and the steel balls 222 will be moved toward the second limiting hole 34 in the second fixing portion 324 of the sliding groove track 32, and when the clamping piece 222 is clamped by the second limiting hole 34, the clamping piece 4 will not be pushed out of the position of the bearing 4, and the clamping piece 122 will not be pushed by the clamping piece 80, and the clamping piece 80 will not be combined with the circuit board 80. In this embodiment, one side of the circuit board 80 is already combined inside the electronic device, so the circuit board 80 is penetrated by the elastic clamping member 42 of the housing 41 of the fixing device through the combining hole 81 and blocks the circuit board 80, so that the circuit board 80 is combined with the substrate 70, but not limited thereto, the circuit board 80 can be designed according to practical requirements, and the circuit board 80 is completely combined with the substrate 70, so the circuit board 80 is provided with a plurality of combining holes 81 and only needs to be matched with a plurality of fixing devices for fixing and combining. In addition, in the present embodiment, the fixing device is used to assemble and fix the circuit board 80 on the substrate 70, but not limited to this, other types of fixing boards (not shown) can be combined on the substrate 70 through the fixing device, so long as the elastic clamping member 42 of the housing 41 of the fixing device passes through and blocks the fixing board to be combined, and the fixing board is combined on the substrate 70.

By means of the design that the elastic clamping piece 42 of the shell 4 can clamp the combining hole 81 of the circuit board 80 and the sleeve 3 can be moved to be linked, the elastic clamping piece 42 of the shell 4 is propped against the protruding piece 122 of the bearing 1, the elastic clamping piece 42 is clamped and combined with the combining hole 81 of the circuit board 80, and the design that the base 11 of the bearing 1 is matched and combined with the base board 70 is adopted, when the sleeve 3 is moved to the combining position, the steel balls 222 of the steel ball springs 22 are clamped into the first limiting holes 33 of the sleeve 3, the elastic clamping piece 42 of the shell 4 is propped and expanded by the protruding piece 122 of the bearing 1 to clamp the circuit board 80, and at the moment, the elastic clamping piece 42 is clamped and combined with the circuit board 80, so that the circuit board 80 is assembled and combined with the base board 70, and the tool-free assembling operation is convenient and efficient.

It should be noted that, in the present embodiment, the chute track 32 of the sleeve 3 further includes two first high portions 322 respectively located on the right side of the first fixing portion 321, two first low portions 323 respectively located on the left side of the first fixing portion 321, two second high portions 325 respectively located on the right side of the second fixing portion 324, and two second low portions 326 respectively located on the left side of the second fixing portion 324. Each first high portion 322, each first fixing portion 321 and each low portion are matched to be in a step shape, and each second high portion 325, each second fixing portion 324 and each second low portion 326 are matched to be in a step shape. The first limiting holes 33 are respectively disposed in the first fixing portions 321 of the chute rails 32, and the second limiting holes 34 are respectively disposed in the second fixing portions 324 of the chute rails 32. When the circuit board 80 is pushed against the housing 41 of the housing 4 toward the substrate 70, the housing 41 drives the cylinder 31 of the sleeve 3 to push against the compression spring 21 of the spring unit 2 toward the substrate 70 and simultaneously moves the steel balls 222 of the steel ball spring 22 away from the second limiting hole 34, and when the steel balls 222 move away from the second limiting hole 34, the steel balls 222 move from the second fixing portion 324 toward the first high portion 322 via the second low portion 326, and the steel balls 222 move from the first high portion 322, and then move into the first fixing portion 321 to the first limiting hole 33. In other words, each second high portion 325, each second fixing portion 324 and each second low portion 326 of the chute track 32 of the sleeve 3 are in a stepped design from high to low, and when the steel ball 222 moves away from the second limiting hole 34, the steel ball 222 moves from the second fixing portion 324 through the second low portion 326 toward the first high portion 322, and the steel ball 222 moves through the first high portion 322 and then moves into the first fixing portion 321 to the first limiting hole 33. Similarly, each first high portion 322, each first fixed portion 321 and each first low portion 323 of the chute track 32 of the sleeve 3 are configured to be in a step shape from high to low, and when the steel ball 222 moves away from the first limiting hole 33, the steel ball 222 moves from the first fixed portion 321 through the first low portion 323 and toward the second high portion 325, and the steel ball 222 moves through the second high portion 325 and then moves into the second fixed portion 324 to the second limiting hole 34. In short, by means of the step-shaped design of each first high portion 322, each first fixing portion 321 and each first low portion 323 of the chute track 32 of the sleeve 3, and the step-shaped design of each second high portion 325, each second fixing portion 324 and each second low portion 326, the steel ball 222 is assisted to move in a single direction and the cylinder 31 is rotated and moved up and down in a single direction, but not limited thereto.

In addition, in the present embodiment, each elastic locking member 42 has an elastic arm 421 extending from the corresponding housing 41 toward the circuit board 80, and an elastic flange 422 extending from the elastic arm 421 toward the circuit board 80. The elastic flanges 422 cooperate to define a pushing space 423 in which the protruding member 122 is extended. When the circuit board 80 is moved toward the substrate 70 and the coupling hole 81 of the circuit board 80 is penetrated by the elastic flange 422 of the elastic locking member 42, and the circuit board 80 is pushed toward the substrate 70 to push the housing 41 of the housing 4, the protrusion 122 of the bearing 1 pushes the elastic arm 421 and stretches into the pushing space 423 to push the elastic flange 422 to expand the elastic flanges 422 away from each other, and when the coupling position is reached, the elastic flange 422 is pushed and expanded by the protrusion 122 of the bearing 1 to block the circuit board 80, and at this time, the elastic locking member 42 is locked and coupled with the circuit board 80. That is, through the design that the elastic flange 422 of the elastic clamping member 42 can be expanded to block the circuit board 80, after the elastic flange 422 of the elastic clamping member 42 passes through the circuit board 80, the circuit board 80 pushes the shell 41 of the housing 4 towards the direction of the substrate 70 to rotate the barrel 31 of the sleeve 3 downwards, so that the protruding member 122 of the bearing 1 pushes the elastic arm 421 upwards to extend into the pushing space 423 and push the elastic flange 422, and the elastic flange 422 gradually expands towards a direction away from each other, and when the sleeve 3 moves to the combining position, the elastic flange 422 is pushed and expanded by the protruding member 122 of the bearing 1 to block the circuit board 80.

In summary, according to the fixing device of the present invention, the elastic clamping member 42 of the housing 4 can clamp the coupling hole 81 of the circuit board 80, and the sleeve 3 can be moved to be interlocked, so that the elastic clamping member 42 of the housing 4 is pushed by the protrusion 122 of the bearing 1, and the elastic clamping member 42 is clamped to couple the coupling hole 81 of the circuit board 80, and the design of combining the base 11 of the bearing 1 to the substrate 70 is combined with the design of combining the elastic clamping member 42 with the base 11 of the bearing 1, so that when the sleeve 3 is moved to the coupling position, the elastic clamping member 42 of the housing 4 is pushed by the protrusion 122 of the bearing 1 to expand to clamp the circuit board 80, and the circuit board 80 is assembled to the substrate 70, so that the assembly is convenient and the tool-free assembly operation is effectively achieved.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims (8)

1. The utility model provides a fixing device, is applicable to a circuit board equipment on a base plate of an electronic device, and this circuit board has a combination hole, and this fixing device sets up on this base plate and extends towards this circuit board's direction from this base plate, characterized in that includes:

The bearing is combined on the substrate and comprises a base part combined on the substrate, and a rod part extending from the base part to the direction of the circuit board, wherein the rod part is provided with a rod body and a protruding piece extending from the rod body to the direction of a combining hole of the circuit board;

The spring unit is combined with the bearing and comprises a compression spring longitudinally surrounding a rod body sleeved with the bearing, and a steel ball spring transversely penetrating through the rod body of the bearing, wherein the steel ball spring is provided with an elastic body penetrating through the rod body, and two steel balls which are arranged at two opposite ends of the elastic body, penetrate out of the rod body and are positioned at two opposite sides of the rod body;

A sleeve surrounding the bearing and combined with the spring unit, comprising a cylinder body combined with the steel ball spring of the spring unit, a chute track which is arranged on the inner side of the cylinder body in a surrounding way and can slide by the steel ball of the steel ball spring, two first limit holes which are arranged in the chute track and can be removably accessed by the steel ball of the steel ball spring, and two second limit holes which are arranged in the chute track and can be removably accessed by the steel ball of the steel ball spring, wherein the cylinder body covers the bearing and can press the compression spring, and the cylinder body is provided with a top part penetrated by a protruding part of the rod part of the bearing, and

The sleeve can move between a combining position and a non-combining position relative to the steel balls of the steel ball spring, when in the combining position, the first limit hole of the sleeve is blocked by the steel balls of the steel ball spring and the elastic blocking piece of the sleeve is blocked by the convex piece of the bearing and enables the elastic blocking piece of the sleeve to be blocked by the convex piece of the bearing, when in the non-combining position, the second limit hole of the sleeve is blocked by the steel balls of the steel ball spring and enables the elastic blocking piece of the sleeve to be blocked by the convex piece of the bearing, when in the non-combining position, the elastic blocking piece of the sleeve is blocked by the steel balls of the steel ball spring and the elastic blocking piece of the sleeve is not blocked by the convex piece of the bearing, the circuit board is moved towards the direction of the substrate and the combination hole of the steel ball spring is blocked by the convex piece of the bearing, when the steel ball spring is blocked by the convex piece of the steel ball spring and the convex piece of the sleeve is pushed by the convex piece of the bearing, when the steel ball spring is pushed by the convex piece of the sleeve and the convex piece of the sleeve is pushed by the convex piece of the bearing, the elastic blocking piece of the steel ball spring is enabled to move towards the position of the steel ball spring and the convex piece of the sleeve is enabled to move towards the convex piece of the steel ball spring and the elastic blocking piece of the steel ball is blocked by the combination hole, and the elastic blocking piece of the steel ball is blocked by the convex piece of the steel plate is blocked by the convex piece, at this time, the elastic clamping piece is fixedly clamped with the circuit board.

2. The fixing device of claim 1, wherein the chute track has two first fixing portions located at two opposite sides in the cylinder and two second fixing portions located at two opposite sides in the cylinder, the two first fixing portions are located above the two second fixing portions, each first fixing portion is located between the two second fixing portions, the first limiting holes are respectively disposed in the two first fixing portions of the chute track, and the second limiting holes are respectively disposed in the two second fixing portions of the chute track.

3. The fixing device as claimed in claim 2, wherein the elastic fastening members of the housing are tapered from the housing toward the circuit board and surround the protruding members of the bearing, each elastic fastening member has an elastic arm tapered from the corresponding housing toward the circuit board and an elastic flange extended from the elastic arm toward the circuit board, the elastic flanges cooperate to define a pushing space for the protruding members to extend, when the circuit board is moved toward the substrate and the coupling hole of the circuit board is penetrated by the elastic flange of the elastic fastening member, and when the circuit board is pushed toward the substrate, the protruding members of the bearing extend into the pushing space and push the elastic flanges to expand the elastic flanges away from each other, and when the coupling position is reached, the elastic flanges are pushed and expanded by the protruding members of the bearing to block the circuit board, and the elastic fastening members are fastened to the circuit board.

4. The fixture of claim 2 wherein the sleeve's chute track further comprises two first high portions located to the right of the two first fixed portions, two first low portions located to the left of the two first fixed portions, two second high portions located to the right of the two second fixed portions, and two second low portions located to the left of the two second fixed portions, each first high portion, each first fixed portion, and each low portion being stepped in cooperation with each second high portion, each second fixed portion, and each second low portion, the first limit holes being located in the two first fixed portions of the chute track, respectively, the second limit holes being located in the two second fixed portions of the chute track, respectively, such that when the circuit board is pushed in the direction of the substrate against the housing of the sleeve, the housing drives the barrel of the sleeve against the spring unit, each second high portion, and each second fixed portion, and each second limit hole being stepped in cooperation with each second low portion, the first limit holes being located in the two second fixed portions of the chute track, the second limit holes being located in the two second fixed portions of the chute track, such that when the circuit board is pushed in the direction of the substrate against the housing, the barrel of the sleeve is pushed in the direction of the spring unit against the spring unit, the second ball is pushed in the direction of the spring unit, and the ball is moved in the direction of the second limit holes are moved from the first limit holes to the second ball portions, and move the ball balls are moved out of the first limit holes and move toward the second ball portions, respectively, and move toward the first limit holes are moved toward the first ball portions.

5. The fixture of claim 1, wherein the base of the bearing is fixedly coupled to the base plate and has a base coupled to the base plate, and a locking member extending from the base plate in a direction toward the base plate and penetrating the base plate and fixedly coupled to the base plate.

6. The fixing device of claim 5, wherein in the coupling position, the first limiting hole of the sleeve is engaged by the steel ball of the steel ball spring, the elastic clamping member of the housing is pushed by the protruding member of the bearing, the elastic clamping member is clamped and coupled with the coupling hole of the circuit board, and the housing of the housing is separated from the base of the bearing by a pre-pressing gap.

7. The fixing device of claim 6, wherein in the coupling position, the housing is separated from the base of the bearing by the pre-pressing gap, so that the housing of the housing can be pushed in a direction away from the base, and when the housing is pushed in a direction away from the base, the housing drives the barrel of the sleeve to move in a direction toward the base to further press the compression spring of the spring unit, and the steel balls are moved out of the first limiting hole in the first fixing portion of the sliding groove rail, and then the housing is not pushed in a direction away from the base, at this time, the elastic restoring force of the compression spring pushes the barrel in a direction away from the base, and rotates the barrel in a direction away from the base, and during the rotation of the barrel, the sliding groove rail in the barrel is simultaneously moved relative to the steel balls and the steel balls are moved in a direction toward the second limiting hole in the second fixing portion of the sliding groove rail, and when the steel balls are blocked into the second limiting hole, the blocking piece is blocked by the steel balls, and the blocking piece is not blocked by the elastic blocking piece.

8. The fixture of claim 1, wherein said shell of the housing is spot glued to the outside of the barrel of the sleeve.