AU2018290469B2

AU2018290469B2 - Seat mounted in driving cab, and vehicle

Info

Publication number: AU2018290469B2
Application number: AU2018290469A
Authority: AU
Inventors: Gongguan LI; Longfei ZHAO
Original assignee: Great Wall Motor Co Ltd
Current assignee: Great Wall Motor Co Ltd
Priority date: 2017-06-28
Filing date: 2018-06-15
Publication date: 2020-11-05
Anticipated expiration: 2038-06-15
Also published as: RU2729328C1; AU2018290469A1; WO2019001295A1; CN108215948B; CN108215948A

Abstract

A seat (100) mounted in a driving cab and a vehicle. The seat (100) comprises a backrest framework (11), a base (20), a recliner assembly (30), side arms (41), a first connecting rod (51), a second connecting rod (52), a third connecting rod (53), and a fourth connecting rod (54). The recliner assembly (30) comprises a first connecting plate (31), a recliner (32), and a second connecting plate (33). The first connecting plate (31) is fixed to the backrest framework (11), and the second connecting plate (33) is selectively fixed to the base (20). The side arms (41) comprise a first side arm (411) and a second side arm (412) that are hingedly connected. The first connecting rod (51) is hingedly connected between the base (20) and the first side arm (411), the second connecting rod (52) is hingedly connected between the second side arm (412) and the third connecting rod (53), and the third connecting rod (53) and the fourth connecting rod (54) are hingedly connected between the second connecting plate (33) and the base (20) respectively. The first connecting rod (51) is located on the front side of the third connecting rod (53), and the fourth connecting rod (54) is located on the front side of the third connecting rod (53). By arranging multiple connecting rods, the seat can be effectively conveyed from a designed use position to a get-on and get-off position of a passenger on a third row, and the height of a seat cushion can be also reduced.

Description

Seat Mounted in Driving Cab, and Vehicle

Field of the Invention The present disclosure relates to the technical field of vehicles, in particular to a seat mounted in a driving cab and a vehicle having the seat.

Background of the Invention In the related art, the side arms of the seat cushion are rigid bodies and are wholly hinged at the rotation axis of the backrest. When the seat is tilted forward wholly, the seat cushion and the backrest rotate forward, i.e., the degree of rotation of the backrest is essentially the same as the degree of rotation of the seat cushion. In order to make the degree of rotation of the seat cushion essentially the same as the degree of rotation of the backrest, it is necessary to increase the height of the seat cushion (otherwise the seat pan may collide and interfere with the floor surface or the slide rails easily), resulting in a great distance from the top surface of the seat cushion to the bottom surfaces of the slide rails, which limits the application of this type of seats to MPVs that have a greater internal space but excludes the application of this type of seats from SUVs that have a smaller internal space. SUVs demand for seats that have small overall thickness, i.e. the distance from the top surface of the seat cushion to the bottom surfaces of the slide rails must be small. Moreover, since the side arms of the seat cushion are rigid bodies, the overall height of the seat pan is decreased greatly when the backrest and the seat cushion rotate forward as a whole. When the seat pan rotates forward to the a position for a passenger in a third row to get on/off the vehicle, the seat pan will encroach on the comfortable handle unlocking range because the seat pan moves forward and downward greatly. Consequently, the handle will be at a position uncomfortable for manipulation, causing inconvenience to the operation of the passenger. Likewise, since the side arms are rigid body structures, the height of the entire seat pan is decreased greatly when the backrest and cushion rotate forward as a whole. As a result, in order to keep away from the position of the slide rail unlocking handle, the anti-submarining position on the seat pan is beyond the design range; in addition, an integral-type seat pan can be used only owing to the limited space; the cost of the mold and parts of the seat pan is high because the seat pan is large in size. Furthermore, manual unlocking of the slide rails is required for the seat to tilt and slide forward wholly. Therefore, the operation is cumbersome and the user experience is poor.

Summary of the Invention In view of the above problems, the object of the present disclosure is to provide a seat mounted in a driving cab, which can solve the problem of excessive height of the seat cushion of the seat. To attain the object described above, the present disclosure employs the following technical scheme: A seat mounted in a driving cab, comprising: a backrest framework; a base; a recliner assembly comprising a first connecting plate, a recliner and a second connecting plate, wherein the first connecting plate and the second connecting plate are connected via the recliner, the first connecting plate is fixed to the backrest framework, and the second connecting plate is selectively fixed to the base; side arms comprising a first side arm and a second side arm, wherein the first side arm is hingedly connected to the front side of the second side arm, and the second side arm is hingedly connected to the first connecting plate; first to fourth connecting rods, wherein the first connecting rod is hingedly connected between the base and the first side arm, the second connecting rod is hingedly connected between the second side arm and the third connecting rod, the third connecting rod and the fourth connecting rod are respectively hingedly connected between the second connecting plate and the base, the first connecting rod is located at the front side of the third connecting rod, and the fourth connecting rod is located at the front side of the third connecting rod; wherein the first connecting rod, the second connecting rod, the first side arm, the second side arm and the base form a five-link mechanism amongst them, the second connecting rod, the second side arm, the third connecting rod, the fourth connecting rod, the base and the recliner assembly form a six-link mechanism amongst them, and the third connecting rod, the fourth connecting rod, the base and the second connecting plate form a four-link mechanism amongst them. Furthermore, the first side arm is hingedly connected between the front end and the rear end of the second side arm, and the top end of the second connecting rod is hingedly connected to the front end of the second side arm. Furthermore, the base comprises a lapping plate, and the bottom ends of the first connecting rod, the third connecting rod and the fourth connecting rod are hingedly connected on the lapping plate. Furthermore, both the third connecting rod and the fourth connecting rod are hingedly connected on the outer side of the lapping plate. Furthermore, the bottom end of the first connecting rod is hingedly connected to the front end of the lapping plate, and the fourth connecting rod is hingedly connected to the rear end of the lapping plate.

Furthermore, the base comprises a fixed rail and a movable rail, wherein the movable rail is movably arranged on the fixed rail, and the lapping plate is fixed on the movable rail. Furthermore, the hinge point of the second connecting rod and the third connecting rod is close to the hinge point of the third connecting rod and the lapping plate. Furthermore, both the second connecting plate and the second side arm are substantially in an L-shape. Furthermore, at least one of the first to fourth connecting rods is provided with a reinforcing rib. Compared with the prior art, the seat disclosed in the present disclosure has the following advantages: According to the seat provided by the present disclosure, the structural strength of the seat can be improved by setting the first side arm and the second side arm, and a new movement form can be formed by setting a plurality of connecting rods, which can effectively conveyed from a designed use position to position for a passenger in the third row to get on/off the vehicle, the height of the seat cushion can be decreased, and the backrest can be leveled to increase the storage space in the entire vehicle. Another object of the present disclosure is to provide a vehicle. To attain the object described above, the present disclosure employs the following technical scheme: A vehicle comprising the seat described above. The vehicle has the same advantages over the prior art as the seat, and will not be detailed further here.

Brief Description of Drawings The accompanying drawings, which constitute a part of the present disclosure, are used to provide a further understanding of the present disclosure. The illustrative embodiments of the present disclosure and their description are used to explain the present disclosure, but don't constitute any undue limitation to the present disclosure. In the figures: Fig. 1 is a schematic structural diagram of the seat in an embodiment of the present disclosure; Fig. 2 is a schematic diagram of the seat; Figs. 3-5 provide schematic structural diagrams of different parts of the seat shown in Fig. 2 respectively; Figs. 6, 8 and 10 are schematic diagrams of the seat when the seam is wholly tilted forward to different angles respectively;

Fig. 7 is a partial schematic diagram at the cam of the seat shown in Fig. 6; Fig. 9 is a partial schematic diagram at the cam of the seat shown in Fig. 8; Fig. 11 is a partial schematic diagram at the cam of the seat shown in Fig. 10; Fig. 12 is a schematic diagram of the seat after the seat is tilted wholly and pushed forward; Figs. 13, 15, 17 and 18 are schematic diagrams of the seat when the backrest is at different angles in the backrest leveling process respectively; Fig. 14 is a partial schematic diagram at the cam of the seat shown in Fig. 13; Fig. 16 is a partial schematic diagram at the cam of the seat shown in Fig. 15; Fig. 19 is a partial schematic diagram at the cam of the seat shown in Fig. 18; Fig. 20 is a schematic structural diagram of the seat in another embodiment different from that shown in Fig. 1; Figs. 21 and 22 are partial schematic diagrams of the second connecting plate having a protruding structure at the seat respectively; Fig. 23 is a schematic diagram of the side arms and connecting rods corresponding to Fig. 20; Fig. 24 is a schematic structural diagram of the seat in yet another embodiment different from that shown in Fig. 1; Fig. 25 is a schematic diagram of the side arms and connecting rods corresponding to Fig. 24.

Brief Description of Symbols: 100 - seat; 10 - backrest; 11 - backrest framework; 20 - base; 21 - fixed rail; 22 - movable rail; 23 - unlocking pin; 24 - lapping plate; 30 - recliner assembly; 31 - first connecting plate; 32 - recliner; 33 - second connecting plate; 34 - protruding structure; 40 - seat cushion; 41 - side arm; 411 - first side arm; 412 - second side arm; 51 - first connecting rod; 52 - second connecting rod; 53 - third connecting rod; 54 - fourth connecting rod; 55 - reinforcing rib; 60 - slide rail unlocking member; 61 - pin roll; 70 - unlocking handle

Detailed Description of the Embodiments It is noted that the embodiments and the features in the embodiments in the present disclosure can be combined freely, provided that there is no confliction among them.

Hereunder the seat 100 mounted in a driving cab according to an embodiment of the present disclosure will be described in detail with reference to Figs. 1-22. The seat 100 may be mounted in a driving cab of a vehicle. As shown in Figs. 1 and 12, the seat 100 according to an embodiment of the present disclosure may comprise: a backrest 10, a recliner assembly 30, a seat cushion 40 and a base 20, wherein the seat cushion 40 is mounted on the base 20, the backrest 10 is mounted on the rear side of the seat cushion 40, and the backrest 10 is rotatable with respect to the base 20 and the seat cushion 40. As shown in Fig. 2, the backrest 10 comprises a backrest framework 11, the recliner assembly 30 comprises a first connecting plate 31, a recliner 32 and a second connecting plate 33, wherein the first connecting plate 31 and the second connecting plate 33 are connected via the recliner 32, the first connecting plate 31 is fixed to the backrest framework 11, and the second connecting plate 33 is selectively fixed on the base 20. The recliner 32 can be used to adjust the angle of the backrest 10 to meet the requirement of the user. The base 20 may be provided with a floor lock that can selectively lock the second connecting plate 33. When the floor lock releases the second connecting plate 33 and the recliner 32 is in a locked state, the seat 100 can be tilted wholly forward. Wherein the recliner assembly 30 may comprise two sets of recliner assemblies, which are respectively arranged on the left side and right side of the backrest framework 11. As shown in Fig. 2, the seat cushion 40 comprises side arms 41, which comprise a first side arm 411 and a second side arm 412, wherein the first side arm 411 is hingedly connected to the front side of the second side arm 412, and the second side arm 412 is hingedly connected to the first connecting plate 31. The second side arm 412 is hingedly connected to the first connecting plate 31, so that the side arms 41 are hingedly connected to the backrest framework 11. Moreover, since the first side arm 411 and the second side arm 412 are hingedly connected, it is equivalent that a supporting connecting rod is added in the middle, thereby the supporting strength for the seat cushion 40 is effectively increased, and the supporting effect for the seat 100 is improved. A link assembly may be provided between the side arms 41 and the base 20. The link assembly may form a plurality of multi-link mechanisms amongst the side arms 41, the base 20 and the backrest 10, and the plurality of multi-link mechanisms may move synergistically. Wherein, as shown in Figs. 2-4, the base 20 comprises a lapping plate 24, on which the connecting rods in the link assembly can be hingedly connected. Specifically, as shown in Figs. 2 and 3, the base 20 further comprises a fixed rail 21 and a movable rail 22, wherein the movable rail 22 is movably arranged on the fixed rail 21, and the lapping plate 24 is fixed on the movable rail 22.

Thus, when the movable rail 22 moves with respect to the fixed rail 21, the seat cushion 40 and the backrest 10 can move synchronously. As shown in Figs. 3 and 4, the link assembly may comprise a first connecting rod 51, a second connecting rod 52, a third connecting rod 53, and a fourth connecting rod 54, wherein the first connecting rod 51 is hingedly connected between the base 20 and the first side arm 411, the third connecting rod 53 and the fourth connecting rod 54 are respectively hingedly connected between the second connecting plate 33 and the base 20, the top end of the second connecting rod 52 is hingedly connected to the second side arm 412, and the bottom end of the second connecting rod 52 is selectively hingedly connected to one of the base 20, the third connecting rod 53, and the fourth connecting rod 54. Optionally, as shown in Fig. 3, at least one of the first connecting rod 51, the second connecting rod 52, the third connecting rod 53, and the fourth connecting rod 54 is provided with a reinforcing rib 55. The reinforcing ribs 55 can effectively increase the structural strength of the corresponding connecting rods, and thereby improve the overall structural strength of the seat 100. Hereunder the hinge form of the second connecting rod 52 will be described separately. According to an alternative embodiment of the present disclosure, as shown in Fig. 3, the second connecting rod 52 is hingedly connected between the second side arm 412 and the base 20. For example, the bottom end of the second connecting rod 52 and the bottom end of the fourth connecting rod 54 are hingedly connected to the same position of the base 20. Wherein the first connecting rod 51.is located at the front side of the third connecting rod 53, and the third connecting rod 53 and the fourth connecting rod 54 are located at the front side and rear side of the second connecting rod 52 respectively. Wherein the first connecting rod 51, the second connecting rod 52, the first side arm 411, the second side arm 412 and the base 20 form a five-link mechanism amongst them, the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, the base 20 and the recliner assembly 30 form a four-link mechanism or five-link mechanism amongst them, and the third connecting rod 53, the fourth connecting rod 54, the base 20 and the second connecting plate 33 form a four-link mechanism amongst them. It should be noted: in the case that the bottom end of the second connecting rod 52 and the bottom end of the fourth connecting rod 54 are hingedly connected to the same position of the base 20, the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, the base 20 and the recliner assembly 30 form a four-link mechanism amongst them; in the case that the bottom end of the second connecting rod 52 and the bottom end of the fourth connecting rod 54 are hingedly connected to different positions of the base 20, the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, the base 20, and the recliner assembly 30 form a five-link mechanism amongst them. Wherein the bottom ends of the first connecting rod 51, the second connecting rod 52, the third connecting rod 53 and the fourth connecting rod 54 are hingedly connected on the lapping plate 24. The base 20 includes only one lapping plate 24, so as to make the structure of the base 20 simple; the plurality of connecting rods are hingedly connected on one lapping plate 24 in a spaced apart manner, so as to ensure the structural compactness and reliability of the seat 100. Furthermore, the second connecting rod 52, the third connecting rod 53, and the fourth connecting rod 54 are hingedly connected on the outer side of the lapping plate 24. In that way, the second connecting rod 52, the third connecting rod 53 and the fourth connecting rod 54 can be easily hingedly connected with other components, and thereby the overall design of the seat 100 is reasonable. Moreover, as shown in Figs. 3 and 4, the bottom end of the first connecting rod 51 is hingedly connected to the front end of the lapping plate 24, and the second connecting rod 52 and the fourth connecting rod 54 are hingedly connected to the rear end of the lapping plate 24. In that way, the length and position of the lapping plate 24 are designed reasonably, the first connecting rod 51 can correspond to the front side of the seat cushion 40, the second connecting rod 52, the third connecting rod 53 and the fourth connecting rod 54 can correspond to the middle part of the seat cushion 40, so that they can support the seat cushion 40 better at the middle part, and the supporting effect for the seat 100 can be improved. According to another alternative embodiment of the present disclosure, as shown in Figs. 20 and 23, the second connecting rod 52 is hingedly connected between the second side arm 412 and the third connecting rod 53, the first connecting rod 51 is located at the front side of the third connecting rod 53, and the fourth connecting rod 54 is located at the front side of the third connecting rod 53. Wherein the first connecting rod 51, the second connecting rod 52, the first side arm 411, the second side arm 412 and the base 20 form a five-link mechanism amongst them, the second connecting rod 52, the second side arm 412, the third connecting rod 53, the fourth connecting rod 54, the base 20 and the recliner assembly 30 form a six-link mechanism amongst them, and the third connecting rod 53, the fourth connecting rod 54, the base 20 and the second connecting plate 33 form a four-link mechanism amongst them. Wherein, as shown in Fig. 20, the bottom ends of the first connecting rod 51, the third connecting rod 53 and the fourth connecting rod 54 are hingedly connected on the lapping plate 24. The base 20 includes only one lapping plate 24, so as to make the structure of the base 20 simple; the plurality of connecting rods are hingedly connected on one lapping plate 24 in a spaced apart manner, so as to ensure the structural compactness and reliability of the seat 100. Furthermore, as shown in Fig. 20, both the third connecting rod 53 and the fourth connecting rod 54 are hingedly connected on the outer side of the lapping plate 24. In that way, the third connecting rod 53 and the fourth connecting rod 54 can be easily hingedly connected with other components, and thereby the overall design of the seat 100 is reasonable. The bottom end of the first connecting rod 51 is hingedly connected to the front end of the lapping plate 24, and the fourth connecting rod 54 is hingedly connected to the rear end of the lapping plate 24. In that way, the length and position of the lapping plate 24 are designed reasonably, the first connecting rod 51 can correspond to the front side of the seat cushion 40, the second connecting rod 52, the third connecting rod 53 and the fourth connecting rod 54 can correspond to the middle part of the seat cushion 40, so that they can support the seat cushion 40 better at the middle part, and the supporting effect for the seat 100 can be improved. Specifically, as shown in Fig. 20, the hinge point of the second connecting rod 52 and the third connecting rod 53 is close to the hinge point of the third connecting rod 53 and the lapping plate 24. In that way, the overall layout of the six-link mechanism is reasonable, effective linkage is realized, and the lowering degree of the seat 100 can be ensured. According to yet another alternative embodiment of the present disclosure, as shown in Figs. 24 and 25, the second connecting rod 52 is hingedly connected between the second side arm 412 and the fourth connecting rod 54, the first connecting rod 51 is located at the front side of the third connecting rod 53, and the fourth connecting rod 54 is located at the front side of the third connecting rod 53. Wherein the first connecting rod 51, the second connecting rod 52, the first side arm 411, the second side arm 412 and the base 20 form a five-link mechanism amongst them, the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, and the recliner assembly 30 form a four-link mechanism, and the third connecting rod 53, the fourth connecting rod 54, the base 20 and the second connecting plate 33 form a four-link mechanism amongst them. Wherein the bottom ends of the first connecting rod 51, the third connecting rod 53 and the fourth connecting rod 54 are hingedly connected on the lapping plate 24. The base 20 includes only one lapping plate 24, so as to make the structure of the base 20 simple; the plurality of connecting rods are hingedly connected on one lapping plate 24 in a spaced apart manner, so as to ensure the structural compactness and reliability of the seat 100. Furthermore, both the third connecting rod 53 and the fourth connecting rod 54 are hingedly connected on the outer side of the lapping plate 24. In that way, the third connecting rod 53 and the fourth connecting rod 54 can be easily hingedly connected with other components, and thereby the overall design of the seat 100 is reasonable. The bottom end of the first connecting rod 51 is hingedly connected to the front end of the lapping plate 24, and the fourth connecting rod 54 is hingedly connected to the rear end of the lapping plate 24. In that way, the length and position of the lapping plate 24 are designed reasonably, the first connecting rod 51 can correspond to the front side of the seat cushion 40, the second connecting rod 52, the third connecting rod 53 and the fourth connecting rod 54 can correspond to the middle part of the seat cushion 40, so that they can support the seat cushion 40 better at the middle part, and the supporting effect for the seat 100 can be improved. The hinge point of the second connecting rod 52 and the fourth connecting rod 54 is close to the hinge point of the fourth connecting rod 54 and the lapping plate 24. In that way, the overall layout of the four-link mechanism is reasonable, effective linkage is realized, and the lowering degree of the seat 100 can be ensured. It should be noted that all of the above three forms of arrangement of the second connecting rod 52 can attain the same effect, with the difference only lying in the position of connection. The working principle when the plurality of connecting rods rotate will further detailed below. Wherein, optionally, as shown in Figs. 3 and 4, the first side arm 411 is hingedly connected between the front end and the rear end of the second side arm 412, and the top end of the second connecting rod 52 is hingedly connected to the front end of the second side arm 412. Optionally, the rear end of the first side arm 411 is hingedly connected between the front end and the rear end of the second side arm 412, and the top end of the second connecting rod 52 is hingedly connected to the front end of the second side arm 412. In that way, the hinge positions of the first side arm 411 and the second side arm 412 are designed reasonably, and the rotation between the first side arm 411 and the second side arm 412 can be facilitated; in addition, the second connecting rod 52 can support the side arms 41 at the front end of the second side arm 412, so as to improve the lateral supporting strength for the seat 100. Specifically, both the second connecting plate 33 and the second side arm 412 are substantially in an L-shape. The L-shaped second connecting plate 33 and the second side ann 412 can adapt to the angle change between the seat cushion 40 and the backrest 10 better, so that the structure of the seat 100 is reliable and the angle change of the seat 100 is stable. As shown in the figures, the lower segment of the second side arm 412 may abut against the base 20, so as to increase the descending amount of the seat cushion 40 and further increase the storage space. The seat 100 configured in the above arrangement can realize the functions of integral forward tilting of the seat 100 and leveling of the backrest 10. However, if the seat 100 is necessary to move the movable rail 22 forward or backward with respect to the fixed rail 21 in the process of integral forward tilting of the seat 100 and leveling of the backrest 10, usually the movable rail 22 has to be unlocked manually, which results in cumbersome operation and poor user experience. In view of that problem, the present disclosure is further improved to unlock the movable rail 22 at the same time when the seat 100 is tilted forward wholly and the backrest 10 is leveled, so as to omit the manual unlocking process of the user. Two different embodiments are provided below. According to a first embodiment of the present disclosure, as shown in Fig. 5, the seat 100 may further comprise a slide rail unlocking member 60 that is linked with one of the first connecting rod 51, the second connecting rod 52, the third connecting rod 53, and the fourth connecting rod 54, and unlocks the movable rail 22 when the linked connecting rod rotates to a certain angle. It should be noted that the rotation angle of the slide rail unlocking member 60 is the same as that of the connecting rod linked with the slide rail unlocking member 60. Thus, when the seat 100 is tilted forward wholly or the backrest 10 is leveled, the link assembly moves in association with the backrest 10, and the slide rail unlocking member 60 rotates accordingly, so that the slide rail unlocking member 60 can effectively unlock the movable rail 22. Specifically, as shown in Fig. 5, the slide rail unlocking member 60 is linked with the second connecting rod 52, which may be hingedly connected together with the fourth connecting rod 54 to the same position of the lapping plate 24. The slide rail unlocking member 60 is a cam, and the movable rail 22 is provided with an unlocking pin 23. The cam is adapted to press the unlocking pin 23 to an unlocking position when the second connecting rod 52 rotates to a certain angle. It can be understood: when the cam is in contact with the top end of the unlocking pin 23, the cam continuously changes its position of contact with the unlocking pin 23 as the cam moves continuously, so that the unlocking pin 23 can be continuously pressed downward, and the unlocking pin 23 continuously moves downward to the unlocking position. When the unlocking pin 23 is in the unlocking position, the movable rail 22 can slide with respect to the fixed rail 21, and the user can move the fixed rail 21 at the same time when adjusting the seat 100, thereby the operation steps of the user can be reduced and the convenience of use can be improved. Optionally, as shown in Fig. 5, a pin roll 61 penetrating the base 20 is fixed on the second connecting rod 52, the cam is fixed on the pin roll 61, and the cam and the second connecting rod 52 are spaced apart by the lapping plate 24 of the base 20. The pin roll 61 can serve as a connection between the second connecting rod 52 and the cam, so that the second connecting rod 52 and the cam can rotate synchronously, and thereby the movable rail 22 can be unlocked synchronously when the seat 100 is adjusted. According to a second embodiment of the present disclosure, as shown in Figs. 21 and 22, the seat 100 further comprises an unlocking handle 70 that selectively unlocks the movable rail 22. For example, the user may manually operate the unlocking handle 70 to unlock the movable rail 22. Wherein the second connecting plate 33 abuts against the unlocking handle 70 after the seat 100 is tilted forward to a certain angle, so as to force the unlocking handle 70 to unlock the movable rail 22. It can be understood: when the seat 100 is tilted forward wholly, the floor lock unlocks the second connecting plate 33, and the second connecting plate 33 can rotate forward, so that it moves from the rear side of the unlocking handle 70 to the top front side of the rear part of the unlocking handle 70, and then abuts against the rear part of the unlocking handle 70. Thus, the floor lock attains the same effect as the manual operation of the unlocking handle 70, and thereby attains the effect of unlocking synchronously as the seat 100 is tilted forward. It should be noted that the integral forward tilting of the seat 100 refers to that the backrest 10 and the seat cushion 40 are tilted forward as a whole with respect to the base 20, i.e., the state of the seat 100 shown in Fig. 12, so that the passenger in the rear seat 100 can get on/off conveniently. Specifically, as shown in Figs. 21 and 22, the second connecting plate 33 is provided with a protruding structure 34, the protruding structure 34 is arranged at the front bottom end of the second connecting plate 33, and is adapted to abut against the rear part of the unlocking handle 70. The protruding structure 34 is advantageous for the second connecting plate 33 to abut against the unlocking handle 70 after rotating to an appropriate angle, so that the seat 100 can be unlocked conveniently and reliably. Optionally, the unlocking handle 70 is provided with an abutting groove fitted with the protruding structure 34. The arrangement of the abutting groove can increase the reliability of fitting between the second connecting plate 33 and the unlocking handle 70, and thereby further improves the unlocking reliability of the movable rail 22 when the seat 100 is tilted forward. Hereunder the working principle of the integral forward tilting of the seat 100 and leveling of the backrest 10 will be described in detail with reference to the seat 100 shown in Fig. 2. Integral forward tilting of the seat 100: as shown in Fig. 5, when the user sits on the seat 100 normally, the cam and the unlocking pin 23 may not be in contact with each other. The seat 100 disclosed in the present disclosure may be a seat 100 in the middle row among three rows of seats 100 (front row, middle row, rear row). When a passenger on the rear row seat 100 wants to get on/off the vehicle, the passenger may use the floor lock to unlock the second connecting plate 33. At that point, the user pushes the backrest 10 forward, as shown in Figs. 6, 8, 10 and

12, the four-link mechanism formed amongst the third connecting rod 53, the fourth connecting rod 54, the base 20 and the second connecting plate 33 rotates forward. A four-link mechanism formed amongst the rear connecting rod (i.e., the fourth connecting rod 54) of the aforesaid four-link mechanism, the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, the base 20 and the recliner assembly 30 has the same fourth connecting rod 54. Since the recliner 32 is in the locked state, the recliner assembly 30 and the backrest framework 11 act as a whole, and the third connecting rod 53 and the second side arm 412 rotate forward. Finally, the front five-link mechanism formed amongst the first connecting rod 51, the second connecting rod 52, the first side arm 411, the second side arm 412 and the base 20 is driven to rotate forward, so that the seat 100 rotates forward wholly (i.e., is tilted forward). In the integral forward tilting process of the seat 100, the second side arm 412 and the backrest 10 connected at the hinge point of the second side arm 412 and the first connecting plate 31 rotate with respect to each other, and the first side arm 411 and the second side arm 412 rotate with respect to each other. Thus, after the seat 100 is tilted forward wholly, the angle between the backrest 10 and the first side arm 411 is changed, thereby the downward rotation angle of the seat cushion 40 can be reduced owing to the change of the aforesaid angle, and the descending amount of the seat cushion 40 of the seat 100 can be relatively small, and the distance between the unlocking handle 70 and the seat pan of the seat 100 can be relatively large. Thus, in such a design, the thickness of the seat 100 can be reduced, and the seat 100 with such a structure has a wider scope of application; besides, since the descending angle of the front end of the seat cushion 40 is not great in the forward tilting process, the slide rail unlocking handle 70 can be maintained within an appropriate comfortable range; moreover, the seat pan part may be a structure formed from profiles (e.g., tubes) and a seat net, and thereby the manufacturing cost of the seat 100 can be reduced. Unlocking with the cam: As shown in Figs. 7, 9 and 11, when the seat 100 is tilted forward wholly, the cam presses the unlocking pin 23 downward till the unlocking pin 23 moves downward to the unlocking position, so that the movable rail 22 can be unlocked. Thus, the seat 100 can slide forward wholly, increasing the space for a passenger in the third row to get on/off the vehicle as much as possible. Moreover, when the seat 100 is tilted forward wholly to the front-most position, the movable rail 22 is still in the unlocked state. The process of returning the seat 100 to the designed use state is reversed to the link movement process described above. The backrest 10 is driven to rotate backward, so that the two four-link mechanisms pull the five-link mechanism backward jointly, thereby the seat 100 rotates backward wholly, till the seat 100 returns to the designed use state.

Unlocking with the protruding structure 34 of the second connecting plate 33: As shown in Figs. 21 and 22, when the seat 100 is tilted forward wholly, the track of the movement trajectory 22 of the protruding structure 34 consists of two stages: 1. forward and upward movement: in this procedure, the protruding structure 34 moves upward, stores energy for the subsequent pressing procedure, and moves forward to approach the rear part of the unlocking handle 70; 2. forward and downward movement: this procedure is mainly a processing procedure, through which the gravity of the seat 100 is directly applied to the rear part of the unlocking handle 70 to realize unlocking, so that the seat 100 can slide forward wholly. It should be noted that either of the above two synchronous unlocking methods for the movable rail 22 can unlock the movable rail 22, and can be selected when the seat 100 is designed and manufactured. Leveling of the backrest 10: As shown in Figs. 13, 15, 17 and 18, the floor lock locked the second connecting plate 33 in the recliner assembly 30, the second connecting plate 33 in the four-link mechanism formed amongst the second connecting rod 52, the second side arm 412, the fourth connecting rod 54, the base 20 and the recliner assembly 30 is a fixed connecting rod, the recliner 32 is switched from a locked state to an unlocked state, the backrest 10 rotates around the rotation axis of the recliner 32, and the second connecting rod 52 rotates forward; moreover, in the five-link mechanism, the connecting rod on the first side arm 411 and the connecting rod on the second side arm 412 have limited the freedom degree of the second connecting rod 52. Therefore, when the four-link mechanism moves, it can push the five-link mechanism to rotate forward, and finally the seat cushion 40 of the seat 100 is lowered wholly, and the backrest 10 rotates forward and is leveled at the same time. Unlocking with the cam in the leveling process of the backrest 10: As shown in Figs. 14, 16 and 19, in the initial position, the cam is not in contact with the unlocking pin 23, and the movable rail 22 is not unlocked at this point. When the backrest 10 rotates forward by 30°, the cam presses the unlocking pin 23 downward to the unlocking position. As the backrest 10 continues rotating forward, the downward pressed amount of the unlocking pin 23 is increased further, till it reaches a maximum value. Then as the cam continues rotating, the downward pressed amount of the unlocking pin 23 is decreased, till the backrest 10 is folded back to 70, and, at this point, the unlocking pin 23 is in a critical unlocking state. In that process, since the movable rail 22 is in the unlocked state, the seat 100 can slide backward to its final position when it is pushed backward; as the backrest 10 is leveled forward further, the cam is gradually separated from the unlocking pin 23, and is completely separated from the unlocking pin 23 when the backrest 10 is leveled completely; at that point, the slide rails return to the locked state. It should be noted that the arrangement of the cam can attain different effects when the seat 100 is tilted forward and when the backrest 10 is leveled, because the second connecting rod 52 rotates by different angles in the two operation processes. Specifically, the second connecting rod 52 rotates by about 800 in the forward tilting process of the seat 100, and rotates by about 115 in the leveling process of the backrest 10. Owing to the different rotation angles, the slide rail unlocking pin is pressed downward in different states. When the seat 100 is tilted forward, the cam can continuously press the slide rail downward; when the backrest 10 is leveled, the slide rail can be unlocked in the middle of the leveling process, the seat 100 can be adjusted backward wholly, and the slide rail is locked again after the backrest 10 is leveled, so as to prevent the seat 100 from sliding. The vehicle according to an embodiment of the present disclosure comprises the seat 100 in the above embodiment. While the present disclosure is described above in some preferred embodiments, the present disclosure is not limited to those preferred embodiments. Any modification, equivalent replacement, and improvement made without departing from the spirit and principle of the present disclosure shall be deemed as falling into the scope of protection of the present disclosure.

Claims

Claims 1. A seat mounted in a driving cab, comprising: a backrest framework; a base; a recliner assembly comprising a first connecting plate, a recliner and a second connecting plate, wherein the first connecting plate and the second connecting plate are connected via the recliner, the first connecting plate is fixed to the backrest framework, and the second connecting plate is selectively fixed to the base; side arms comprising a first side arm and a second side arm, wherein the first side arm is hingedly connected to the front side of the second side arm, and the second side arm is hingedly connected to the first connecting plate; first to fourth connecting rods, wherein the first connecting rod is hingedly connected between the base and the first side ann, the second connecting rod is hingedly connected between the second side arm and the third connecting rod , the third connecting rod and the fourth connecting rod are hingedly connected between the second connecting plate and the base respectively, the first connecting rod is located at the front side of the third connecting rod, and the fourth connecting rod is located at the front side of the third connecting rod; wherein the first connecting rod, the second connecting rod, the first side arm, the second side arm and the base form a five-link mechanism amongst them, the second connecting rod, the second side arm, the third connecting rod, the fourth connecting rod, the base and the recliner assembly form a six-link mechanism amongst them, and the third connecting rod, the fourth connecting rod, the base and the second connecting plate form a four-link mechanism amongst them.
2. The seat mounted in a driving cab according to claim 1, wherein, the first side arm is hingedly connected between the front end and the rear end of the second side arm, and the top end of the second connecting rod is hingedly connected to the front end of the second side arm.
3. The seat mounted in a driving cab according to claim 1 or claim 2, wherein, the base comprises a lapping plate, and the bottom ends of the first connecting rod, the third connecting rod and the fourth connecting rod are hingedly connected on the lapping plate.
4. The seat mounted in a driving cab according to any one of the preceding claims, wherein, both the third connecting rod and the fourth connecting rod are hingedly connected on the outer side of the lapping plate.
5. The seat mounted in a driving cab according to any one of the preceding claims, wherein, the bottom end of the first connecting rod is hingedly connected to the front end of the lapping plate, and the fourth connecting rod is hingedly connected to the rear end of the lapping plate.
6. The seat mounted in a driving cab according to any one of the preceding claims, wherein, the base comprises a fixed rail and a movable rail, wherein the movable rail is movably arranged on the fixed rail, and the lapping plate is fixed on the movable rail.
7. The seat mounted in a driving cab according to any one of the preceding claims, wherein, the hinge point of the second connecting rod and the third connecting rod is close to the hinge point of the third connecting rod and the lapping plate.
8. The seat mounted in a driving cab according to any one of the preceding claims, wherein, both the second connecting plate and the second side arm are substantially in an L-shape.
9. The seat mounted in a driving cab according to any one of the preceding claims, wherein, at least one of the first to fourth connecting rods (51, 52, 53, and 54) is provided with a reinforcing rib.
10. A vehicle comprising the seat mounted in a driving cab according to any one of claims 1-9.