CN112971407A

CN112971407A - Sliding rail assembly

Info

Publication number: CN112971407A
Application number: CN201911308823.XA
Authority: CN
Inventors: 陈庚金; 杨顺和; 游凯文; 王俊强
Original assignee: King Slide Works Co Ltd; King Slide Technology Co Ltd
Current assignee: King Slide Works Co Ltd; King Slide Technology Co Ltd
Priority date: 2019-12-18
Filing date: 2019-12-18
Publication date: 2021-06-18
Anticipated expiration: 2039-12-18
Also published as: CN112971407B

Abstract

The invention relates to a slide rail assembly, which comprises a first rail and a second rail. The first rail has a plurality of walls defining a channel and is provided with a blocking feature. The second rail is provided with a fool-proof feature. When the second rail is turned by a predetermined angle relative to the first rail and is installed from the outside of the channel into the channel, the fool-proof feature and the blocking feature block each other, so that the second rail cannot be allowed to be folded relative to the first rail.

Description

Sliding rail assembly

Technical Field

The present invention relates to a slide rail, and more particularly to a slide rail assembly with fool-proof function.

Background

Generally, the slide assembly has a plurality of slides, for example, a first rail and a second rail can move relative to each other. Wherein the first rail has a channel for receiving the second rail. However, sometimes the use of the slide rail assembly does not allow the second rail to be incorrectly installed in the channel of the first rail due to specific requirements, and therefore, how to develop a slide rail assembly capable of preventing two slide rails from being incorrectly installed relative to each other becomes an issue which cannot be ignored.

Disclosure of Invention

The invention aims to provide a slide rail assembly with a fool-proof mechanism.

According to one aspect of the present invention, a slide rail assembly includes a first rail, a blocking feature, a second rail, and a fool-proof feature. The first rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the first rail, and the first wall, the second wall and the longitudinal wall of the first rail define a channel together; the blocking feature is arranged on the first rail and is positioned on a first wall adjacent to the first rail; the second rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the second rail; the fool-proof feature is arranged on the second rail and is positioned on a second wall adjacent to the second rail; when the first wall of the second rail is positioned adjacent to the second wall of the first rail and inserted into the channel of the first rail, the fool-proof feature and the blocking feature block each other, so that the second rail cannot be folded relative to the first rail.

Preferably, the slide rail assembly comprises a stopper fixed to the front end of the adjacent first rail, and the stopper has the stopping feature.

Preferably, the slide rail assembly includes a fool-proof member movably mounted to the second rail, and the fool-proof member has the fool-proof feature.

Preferably, the fool-proof member is pivotally connected to the second rail.

Preferably, the slide assembly further comprises an elastic member for providing an elastic force to the fool-proof member.

According to another aspect of the present invention, a slide rail assembly includes a first rail, a blocking feature, a second rail, and a fool-proof feature. The first rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the first rail, and the first wall, the second wall and the longitudinal wall of the first rail define a channel together; the blocking feature is arranged on the first rail and is positioned on a first wall adjacent to the first rail; the second rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the second rail; the fool-proof feature is arranged on the second rail and is positioned on a second wall adjacent to the second rail; when the first wall of the second rail is located adjacent to the first wall of the first rail and is inserted into the channel of the first rail from the outside of the channel of the first rail in a folding direction, the fool-proof feature and the blocking feature are not blocked mutually so as to allow the second rail to be folded relative to the first rail.

Preferably, the fool-proof member is pivotally connected to the second rail.

Preferably, the slide rail assembly further comprises an elastic member, and the fool-proof member is kept in a predetermined state in response to the elastic force generated by the elastic member.

Preferably, the slide assembly further comprises a guide feature located on a second wall adjacent the first rail; when the first wall of the second rail is positioned adjacent to the first wall of the first rail and inserted into the channel of the first rail, the fool-proof piece can be guided by the guiding feature to move, so that the fool-proof piece passes through the guiding feature to allow the second rail to be folded relative to the first rail.

Preferably, the slide rail assembly further comprises a first working member and a second working member movably mounted to the second rail; when the second rail moves from a retracted position to an open position relative to the first rail, the first and second working members are respectively located at a first and second portion of the blocking feature to maintain the second rail at the extended position.

Preferably, the first and second working members are pivotally connected to the second rail through a first shaft and a second shaft, respectively.

Preferably, the slide rail assembly further comprises a first elastic feature and a second elastic feature for providing elastic force to the first working piece and the second working piece, respectively.

Preferably, the slide assembly further comprises a first operating member and a second operating member operatively connected to the first operating member and the second operating member, respectively.

According to another aspect of the present invention, a sliding rail assembly includes two first rails and a second rail. The two first rails have substantially the same structural configuration, each first rail defines a channel, and each first rail is provided with a blocking feature; the second rail is provided with a fool-proof feature; when the second rail is inserted into the channel of one of the two first rails from the outside of the channel of one of the two first rails in a folding direction, the fool-proof feature and the blocking feature of one of the two first rails are not blocked with each other so as to allow the second rail to be folded relative to one of the two first rails in the folding direction; when the second rail is turned by a predetermined angle relative to the other of the two first rails and is inserted into the other of the two first rails from the outside of the other of the two first rails in the retracting direction, the fool-proof feature and the blocking feature of the other of the two first rails block each other, so that the second rail cannot be retracted relative to the other of the two first rails in the retracting direction.

Preferably, the predetermined angle is substantially 180 degrees.

Preferably, the first rail has a first wall, a second wall and a longitudinal wall connected between the first wall and the second wall of the first rail, the first wall, the second wall and the longitudinal wall of the first rail defining the channel together; the blocking feature is located on a first wall adjacent the first rail.

Preferably, the second rail has a first wall, a second wall and a longitudinal wall connected between the first wall and the second wall of the second rail; the fool-proof feature is located on a second wall adjacent to the second rail.

Preferably, a stopper is disposed adjacent to the front end of the first rail, and the stopper has the blocking feature; the slide rail assembly comprises a fool-proof piece movably mounted to the second rail, and the fool-proof piece has the fool-proof feature; and an elastic member for providing an elastic force to the fool-proof member.

Drawings

For further explanation of the above objects, structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings, in which:

fig. 1 is a schematic perspective view illustrating a slide rail assembly in an extended state according to an embodiment of the present invention.

Fig. 2 is an exploded view of the slide rail assembly according to the embodiment of the invention.

FIG. 3 is a schematic view of a stopper and an elastic base of a sliding rail assembly according to an embodiment of the invention.

Fig. 4 is a schematic view illustrating a slide rail assembly in a retracted state according to an embodiment of the present invention.

Fig. 5 is a schematic view illustrating a first rail and a second rail of the slide rail assembly of the embodiment of the invention moving in an opening direction relative to a third rail.

Fig. 6 is a schematic view illustrating that the first rail of the slide rail assembly is at a first extending position relative to the third rail, and the second rail is displaced in the opening direction relative to the first rail according to the embodiment of the invention.

Fig. 7 is a schematic view illustrating that the first rail of the slide rail assembly is at the first extended position relative to the third rail, and the second rail is continuously displaced in the opening direction relative to the first rail according to the embodiment of the invention.

Fig. 8 shows a schematic view of the slide rail assembly in the extended state according to the embodiment of the invention.

FIG. 9 is a schematic view of the slide rail assembly in the extended state and a working member being operated by an operating member according to the embodiment of the invention.

Fig. 10 is a schematic view of the slide rail assembly in the extended state and the second rail can be displaced in the opening direction by the movement of the working member according to the embodiment of the invention.

Fig. 11 is a schematic view illustrating that the second rail of the slide rail assembly according to the embodiment of the invention can be moved in the opening direction to be detached from the first rail.

Fig. 12 is a schematic view illustrating the second rail of the slide rail assembly according to the embodiment of the invention being installed to the first rail in a retracting direction.

Fig. 13 is a schematic view illustrating the second rail of the slide rail assembly of the embodiment of the invention being continuously mounted to the first rail in the retracting direction.

Fig. 14 is a schematic view illustrating the slide rail assembly of the embodiment of the invention having a fool-proof feature, wherein the second rail is installed toward the other first rail in the retracting direction.

Fig. 15 is a schematic view illustrating that the slide rail assembly according to the embodiment of the present invention has the fool-proof feature, so that the second rail cannot be further installed to the other first rail in the folding direction through the fool-proof feature.

Detailed Description

As shown in fig. 1 and 2, the slide rail assembly 20 of the embodiment of the present invention includes a first rail 22 and a second rail 24, and preferably further includes a third rail 26. Wherein the first rail 22 is movably mounted between the third rail 26 and the second rail 24.

The third rail 26 includes a plurality of walls defining a channel 27 for receiving the first rail 22.

The first rail 22 is longitudinally displaceable relative to the third rail 26. The first rail 22 has a front end 22a and a rear end 22 b. The first rail 22 has a first wall 28a, a second wall 28b and a longitudinal wall 30 connected between the first wall 28a and the second wall 28b of the first rail 22, the first wall 28a, the second wall 28b and the longitudinal wall 30 of the first rail 22 together defining a channel 32 for receiving the second rail 24. Preferably, a sliding aid 33 is movably disposed in the channel 32 of the first rail 22 to facilitate displacement of the second rail 24 relative to the first rail 22. Wherein the first rail 22 is provided with a stop feature 34. The stop feature 34 is positioned within the channel 32 of the first rail 22, and the stop feature 34 is positioned adjacent the first wall 28a of the first rail 22. In addition, a pair of guiding blocks 35 is disposed at the front end 22a of the first rail 22 and abuts against the first wall 28a and the second wall 28b of the first rail 22 for blocking the sliding aid 33 and for supporting and guiding the second rail 24 inserted into the first rail 22.

The second rail 24 has a front end 24a and a rear end 24 b. The second rail 24 has a first wall 36a, a second wall 36b and a longitudinal wall 38 connected between the first wall 36a and the second wall 36b of the second rail 24. The rear end 24b of the second rail 24 is insertable into the front end 22a of the first rail 22 such that the second rail 24 is longitudinally displaceable relative to the first rail 22. Wherein, the second rail 24 is provided with a fool-proof feature 40, and the fool-proof feature 40 is located on the second wall 36b adjacent to the second rail 24.

Preferably, the slide assembly 20 includes a stopper 42 (please refer to fig. 3) fixed adjacent to the front end 22a of the first rail 22, and the stopper 42 has the stopping feature 34. Further, the stopper 42 has a body portion 44 connected (e.g., fixedly connected) to the longitudinal wall 30 of the first rail 22, and the stopping feature 34 projects laterally (or laterally) relative to the body portion 44.

Preferably, the track assembly 20 includes a guide feature 46 (see also fig. 3) located adjacent the second wall 28b of the first track 22. The guide feature 46 comprises a slope or a curved surface, and the guide feature 46 can be integrated into the first rail 22; alternatively, in this embodiment, the guide feature 46 is integrated on a resilient base 48, but the implementation is not limited thereto. Further, the resilient base 48 has a connecting portion 50 connected (e.g., fixedly connected) to the longitudinal wall 30 of the first rail 22, and the guide feature 46 is adjacent to the connecting portion 50.

Preferably, the elastic base 48 includes an elastic arm 47 connected to the connecting portion 50 (please refer to fig. 3), and the elastic arm 47 has the guiding feature 46 and a locking portion 49 at two corresponding ends. When the second rail 24 is pulled out relative to the first rail 22 to drive the sliding aid 33 to move to the position adjacent to the front end 22a of the first rail, the locking portion 49 can be locked with a predetermined position of the sliding aid 33, so that the sliding aid 33 temporarily stays at the position of the front end 22 a. On the other hand, the stopper 42 further has a supporting portion 51 for supporting the elastic arm 47.

Preferably, in conjunction with fig. 4, the slide rail assembly 20 includes a fool-proof member 52 movably mounted to the second rail 24, and the fool-proof member 52 has the fool-proof feature 40. In this embodiment, the fool-proof member 52 is pivoted to the longitudinal wall 38 of the second rail 24 through a connecting shaft 54, but the embodiment is not limited thereto. In addition, the fool-proof member 52 has a guiding surface 53, and the guiding surface 53 may be an inclined surface or an arc surface, which is not limited in implementation.

Preferably, the slide assembly 20 further includes an elastic member 56, and the fool-proof member 52 is capable of being maintained in a predetermined state in response to the elastic force generated by the elastic member 56. Here, for example, the elastic member 56 has an elastic section 58 for providing elastic force to the fool-proof member 52.

Preferably, the slide assembly 20 includes a first operating member 60 and a second operating member 62 movably mounted to the second rail 24. Here, the first operating member 60 is pivoted to the longitudinal wall 38 of the second rail 24 through a first shaft 64, and the second operating member 62 is pivoted to the longitudinal wall 38 of the second rail 24 through a second shaft 66, but the embodiment is not limited thereto.

Preferably, the slide assembly 20 further includes a first resilient feature 68 and a second resilient feature 70 for providing resilient force to the first and second working

members

60 and 62, respectively. Here, it is exemplified that the first elastic feature 68 and the second elastic feature 70 are integrated in an elastic seat 72, and both the first elastic feature 68 and the second elastic feature 70 are elastic arms. It should be noted that in other embodiments, the first elastic feature 68 and the second elastic feature 70 can be two independent components disposed on the second rail 24, and therefore, the implementation is not limited.

Preferably, the slide assembly 20 includes an operating member for operating one of the first and second working

members

60, 62. Herein, a first operation element 74 and a second operation element 76 are taken as examples. The first operating member 74 and the second operating member 76 operatively connect the first operating member 60 and the second operating member 62, respectively.

As shown in fig. 4, the slide rail assembly 20 is in a retracted state. The first rail 22 is folded relative to the third rail 26, and the second rail 24 is located at a folded position R relative to the first rail 22. It is worth mentioning that the first wall 36a of the second rail 24 is located adjacent to the first wall 28a of the first rail 22, and the second wall 36b of the second rail 24 is located adjacent to the second wall 28b of the first rail 22. Wherein the first and second working

members

60, 62 are respectively in a first working state S1 in response to the elastic force of the first and second

elastic features

68, 70, and the positions of the first and second working

members

60, 62 correspond to the stop feature 34 of the first rail 22; on the other hand, the location of the fool-guard 52 does not correspond to the stop feature 34 of the first rail 22 (i.e., the fool-guard feature 40 is offset from the stop feature 34). The stop feature 34 has a first portion 34a and a second portion 34b that are oppositely located.

As shown in fig. 5, the first rail 22 is movable relative to the third rail 26 in an opening direction D1 to a first extended position E1.

As shown in fig. 6, when the first rail 22 is at the first extended position E1 relative to the third rail 26, the second rail 24 can be displaced relative to the first rail 22 in the opening direction D1. Wherein, during the displacement of the second rail 24 relative to the first rail 22 in the opening direction D1, the first working member 60 contacts the second portion 34b of the stop feature 34 to generate a force due to the position of the first working member 60 corresponding to the stop feature 34 of the first rail 22.

As shown in fig. 6 and 7, during the continued displacement of the second rail 24 relative to the first rail 22 in the opening direction D1, the first working member 60 is angularly deflected from the first working state S1 (shown in fig. 6) to a second working state S2 (shown in fig. 7) in response to the force, such that the first working member 60 can pass over the second portion 34b of the blocking feature 34. At this point, the first resilient feature 68 is in a state of accumulating a resilient force (as shown in FIG. 7).

As shown in fig. 7 and 8, when the second rail 24 is further displaced relative to the first rail 22 in the opening direction D1 to a second extended position E2, the first working member 60 returns to the first working state S1 in response to the first resilient feature 68 releasing the resilient force, such that the first working member 60 is located at the first portion 34a of the blocking feature 34 (as shown in fig. 8); on the other hand, since the position of the second working member 62 in the first working state S1 corresponds to the stop feature 34 of the first rail 22, the second working member 62 contacts the second portion 34b of the stop feature 34. At this time, the first and second working

members

60 and 62 are both in the first working state S1 and located at the first and

second portions

34a and 34b of the blocking feature 34, respectively, for maintaining the second rail 24 in the second extended position E2 (as shown in fig. 8).

As shown in fig. 8 to 11, when the second rail 24 is located at the second extended position E2 (as shown in fig. 8) relative to the first rail 22, a user can apply a force F (as shown in fig. 9) to operate the second operating member 76 to drive the second operating member 62 to switch from the first operating state S1 to the second operating state S2 (as shown in fig. 9 and 10) so as to allow the second rail 24 to be detached from the second extended position E2 relative to the first rail 22 in the opening direction D1 (as shown in fig. 11). In other words, the second rail 24 can be disengaged from the channel 32 of the first rail 22. Since the position of the fool-proof member 52 does not correspond to the stopping feature 34 of the first rail 22 (the fool-proof member 52 is offset from the stopping feature 34), when the second rail 24 is displaced toward the opening direction D1, the fool-proof member 52 is not stopped by the stopping feature 34, and the fool-proof member 52 passes over the latch portion 49 of the elastic arm 47 through the guiding surface 53.

As shown in fig. 11, 12 and 13, the stop feature 34 is located adjacent to the first wall 28a of the first rail 22 and the fool-proof feature 40 is located adjacent to the second wall 36b of the second rail 24. The second rail 24 is mountable into the channel 32 of the first rail 22 in a retracted direction D2 from outside the channel 32 of the first rail 22. Further, in a proper installation procedure, for example, when the first wall 36a of the second rail 24 is positioned adjacent to the first wall 28a of the first rail 22 and inserted into the channel 32 of the first rail 22 in the retracting direction D2, the fool-proof feature 40 and the blocking feature 34 are not blocked from each other.

In detail, since the guiding feature 46 is located on the second wall 28b adjacent to the first rail 22, when the first wall 36a of the second rail 24 is located on the first wall 28a adjacent to the first rail 22 and inserted into the channel 32 of the first rail 22, the fool-proof member 52 can be guided by the guiding feature 46 to move (for example, the fool-proof member 52 pivots to an angle as shown in fig. 13), so that the fool-proof member 52 passes through the guiding feature 46 to allow the second rail 24 to be folded relative to the first rail 22 in the folding direction D2. Preferably, as shown in fig. 13, when the fool-proof member 52 is guided by the guiding feature 46, the elastic section 58 of the elastic member 56 accumulates an elastic force in response to the movement of the fool-proof member 52, so that the fool-proof member 52 is no longer in the predetermined state, and the second rail 24 is allowed to be folded relative to the first rail 22 in the folding direction D2 to the folding position R, as shown in fig. 4.

As shown in fig. 14 and 15, different from the embodiment shown in fig. 12 and 13, in short, in practical installation, the slide rail assemblies are respectively installed on the left and right sides of a load-bearing object. It can be understood that the above-mentioned embodiment of fig. 12 and 13 is installed on the left side of the carrier, and fig. 14 and 15 are installed on the right side of the carrier, and when the second rail 24 originally belonging to the left slide rail assembly is turned over a predetermined angle to be installed on the right slide rail assembly (i.e. another first rail 200), an installation error is generated. The structural configuration of the first rail 200 is substantially the same as that of the first rail 22.

Further, in a wrong installation procedure, when the second rail 24 is turned over by the predetermined angle relative to the first rail 200, the second rail 24 cannot be installed into the channel 32 of the first rail 200 from the outside of the channel 32 of the first rail 200 in the folding direction D2. For example, when the first wall 36a of the second rail 24 is located adjacent to the second wall 28b of the first rail 200 and is inserted into the channel 32 of the first rail 200 from the outside of the channel 32 of the first rail 200 in the retracting direction D2, the fool-proof feature 40 and (the first portion 34a of) the blocking feature 34 of the first rail 200 block each other (as shown in fig. 15), so that the second rail 24 cannot be retracted to the retracted position R in the retracting direction D2 relative to the first rail 200. Wherein the predetermined angle is substantially 180 degrees. (the first wall 36a and the second wall 36b of the second rail 24 shown in fig. 14 and 15 are respectively located at the lower position and the upper position of the longitudinal wall 38 of the second rail 24, compared to the first wall 36a and the second wall 36b of the second rail 24 shown in fig. 12 and 13 which are respectively located at the upper position and the lower position of the longitudinal wall 38 of the second rail 24).

From the above description, it can be seen that the enhanced efficacy and advantages of the present invention are:

a. by the mating of the fool-proof feature 40 and the stop feature 34, a user is prevented from mistakenly mounting the second rail 24 into the channel 32 of the first rail 22 (200).

b. By matching the fool-proof feature 40 and the blocking feature 34, when two sets of slide rail assemblies 20 (such as a first slide rail assembly and a second slide rail assembly) having the above-mentioned structural configuration are applied to the left and right sides of a rack system (or drawer system), for example: the second rail 24 of the left first slide assembly can only be mounted into the channel 32 of the first rail 22 of the left first slide assembly, in other words, the second rail 24 of the left first slide assembly cannot be mounted into the channel 32 of the first rail 200 of the right first slide assembly; and vice versa.

Although the present invention has been described with reference to the present specific embodiments, it will be recognized by those skilled in the art that the above embodiments are illustrative only, and various equivalent changes and modifications may be made without departing from the spirit of the present invention, and therefore, it is intended to cover in the appended claims all such changes and modifications as fall within the true spirit of the invention.

Claims

1. A slide rail assembly comprises a first rail and a second rail, and is characterized in that:

the first rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the first rail, and the first wall, the second wall and the longitudinal wall of the first rail define a channel together;

a blocking feature disposed on the first rail, the blocking feature being located on a first wall adjacent to the first rail;

the second rail is provided with a first wall, a second wall and a longitudinal wall which are connected between the first wall and the second wall of the second rail; and

a fool-proof feature disposed on the second rail and located on a second wall adjacent to the second rail;

when the first wall of the second rail is positioned adjacent to the second wall of the first rail and inserted into the channel of the first rail, the fool-proof feature and the blocking feature block each other, so that the second rail cannot be folded relative to the first rail.

2. The slide rail assembly of claim 1 further comprising a stop member secured adjacent the front end of the first rail, the stop member having the stop feature.

3. The slide rail assembly of claim 2 further comprising a fool-proof member movably mounted to the second rail, the fool-proof member having the fool-proof feature.

4. The slide rail assembly of claim 3 wherein the fool-proofing member is pivotally connected to the second rail.

5. The slide rail assembly of claim 3 further comprising a resilient member for providing a resilient force to the fool-proof member.

6. A slide rail assembly comprises a first rail and a second rail, and is characterized in that:

when the first wall of the second rail is located adjacent to the first wall of the first rail and is inserted into the channel of the first rail from the outside of the channel of the first rail in a folding direction, the fool-proof feature and the blocking feature are not blocked mutually so as to allow the second rail to be folded relative to the first rail.

7. The slide rail assembly of claim 6 further comprising a stop member affixed adjacent the front end of the first rail, the stop member having the stop feature.

8. The slide rail assembly of claim 7 further comprising a fool-proof member movably mounted to the second rail, the fool-proof member having the fool-proof feature.

9. The slide rail assembly of claim 8 wherein the fool guard is pivotally coupled to the second rail.

10. The slide rail assembly of claim 8 further comprising a resilient member, wherein the fool-proofing member is maintained in a predetermined state in response to a resilient force generated by the resilient member.

11. The slide rail assembly of claim 10 further comprising a guide feature located on a second wall adjacent the first rail; when the first wall of the second rail is positioned adjacent to the first wall of the first rail and inserted into the channel of the first rail, the fool-proof piece can be guided by the guiding feature to move, so that the fool-proof piece passes through the guiding feature to allow the second rail to be folded relative to the first rail.

12. The slide rail assembly of claim 6 further comprising a first working member and a second working member movably mounted to the second rail; when the second rail moves from a retracted position to an open position relative to the first rail, the first and second working members are respectively located at a first and second portion of the blocking feature to maintain the second rail at the extended position.

13. The slide rail assembly of claim 12 wherein the first and second working members are pivotally coupled to the second rail by a first and second axis, respectively.

14. The slide rail assembly of claim 13 further comprising a first resilient feature and a second resilient feature for providing spring force to the first and second working members, respectively.

15. The slide rail assembly of claim 13 further comprising a first operating member and a second operating member operatively connecting the first operating member and the second operating member, respectively.

16. A slide rail assembly comprises two first rails and a second rail, and is characterized in that:

the two first rails have substantially the same structural configuration, each first rail defines a channel, and each first rail is provided with a blocking feature; and

the second rail is provided with a fool-proof feature;

when the second rail is inserted into the channel of one of the two first rails from the outside of the channel of one of the two first rails in a folding direction, the fool-proof feature and the blocking feature of one of the two first rails are not blocked with each other so as to allow the second rail to be folded relative to one of the two first rails in the folding direction;

when the second rail is turned by a predetermined angle relative to the other of the two first rails and is inserted into the other of the two first rails from the outside of the other of the two first rails in the retracting direction, the fool-proof feature and the blocking feature of the other of the two first rails block each other, so that the second rail cannot be retracted relative to the other of the two first rails in the retracting direction.

17. The slide rail assembly of claim 16 wherein the predetermined angle is substantially 180 degrees.

18. The slide rail assembly of claim 17 wherein the first rail has a first wall, a second wall, and a longitudinal wall connected between the first wall and the second wall of the first rail, the first wall, the second wall, and the longitudinal wall of the first rail collectively defining the channel; the blocking feature is located on a first wall adjacent the first rail.

19. The slide rail assembly of claim 18 wherein the second rail has a first wall, a second wall, and a longitudinal wall connected between the first wall and the second wall of the second rail; the fool-proof feature is located on a second wall adjacent to the second rail.

20. The slide rail assembly of claim 16 wherein a stop is disposed adjacent the front end of the first rail, the stop having the blocking feature; the slide rail assembly comprises a fool-proof piece movably mounted to the second rail, and the fool-proof piece has the fool-proof feature; and an elastic member for providing an elastic force to the fool-proof member.