seat

Abstract

This document discloses an example of a seat that takes into consideration the fact that if a large external force that pulls the entire side frame toward the rear is applied to the side frame, the front end of the seat cushion may unintentionally be displaced upward. [Solution] The connection center between the first drive-side link 71A and the second drive-side link 71B (hereinafter referred to as the moving center Om) is located behind the second center O2. Furthermore, in the normal position, the moving center Om is located higher than the center line Lc. As a result, when an external force Fo acts on the first side frame 11, a force F1 acts on the second center O2, i.e., the front rod member 13, which reduces the angle θ1 between the first drive-side link 71A and the second drive-side link 71B. Therefore, it is possible to suppress the unintended upward displacement of the front end of the seat cushion 3.

Description

Technical Field

[0001] The present disclosure relates to a seat capable of vertically displacing one end side in the front-rear direction of a seat cushion.

Background Art

[0002] For example, the vehicle seat described in Patent Document 1 includes a posture changing mechanism that vertically displaces the front end side of the seat cushion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A side frame (also referred to as a lower arm) that forms part of a cushion frame is a strength member extending in the front-rear direction of the seat. For example, when a large external force that pulls the entire side frame to the rear side is input to the side frame, in the invention described in Patent Document 1, there is a risk that the front end side of the seat cushion may be unintentionally lifted and displaced. The present disclosure discloses an example of a seat in view of this point.

Means for Solving the Problems

[0005] A seat capable of vertically displacing one end side in the front-rear direction of a seat cushion (3) preferably includes at least one of the following constituent requirements, for example. In other words, the constituent element is a side frame (11) that extends in the front-rear direction of the seat and constitutes a part of the cushion frame (10), and has connecting parts (5A, 5C) that are directly or indirectly rotatably connected to the base member (9A) at the other end in the extension direction of the side frame (11), and a posture changing mechanism (71) having a first link (71A) and a second link (71B) for connecting the other end of the side frame (11) in the extension direction to the base member (9A), and the posture changing mechanism (71) causes the front-rear end of the seat cushion (3) to be raised or lowered by changing the angle between the first link (71A) and the second link (71B).

[0006] Furthermore, when the connection point between the first link (71A) and the second link (71B) is defined as the center of movement (Om), the center of movement (Om) is located behind the second center (O2). Moreover, it is desirable that the center of movement (Om) is at the same height as the center line (Lc) or higher than the center line (Lc) when at least one end of the seat cushion (3) is lowered in the normal position.

[0007] The lower end of the first link (71A) is rotatably connected to the base member (9A), the lower end of the second link (71B) is rotatably connected to the upper end of the first link (71A), and the upper end of the second link (71B) is rotatably connected to the side frame (11).

[0008] The first center (O1) is the connection center between the connecting parts (5A, 5C) and the side frame (11), the second center (O2) is the connection center between the second link (71B) and the side frame (11), and the centerline (Lc) is an imaginary line extending in the front-rear direction through the first center (O1) and the second center (O2).

[0009] As a result, when the above external force acts on the side frame (11), a force acts on the second center (O2) that reduces the angle between the first link (71A) and the second link (71B). In other words, when the above-mentioned external force acts on the side frame (11) of the seat, a force is generated in the seat cushion that causes one end of the seat cushion to fall downward. Therefore, it is possible to suppress the unintended upward displacement of one end of the seat cushion.

[0010] The sheet may also have the following configuration, for example. The connecting portion is connected to the base member (9A) via a lifter link (5A), the lower end of which the lifter link (5A) is rotatably connected to the base member (9A), and the upper end of which is rotatably connected to the side frame (11) at the first center (O1), and furthermore, it is desirable that the entire seat cushion (3) moves up and down as the lifter link (5A) swings and displaces relative to the base member (9A) while the angle between the first link (71A) and the second link (71B) is constant.

[0011] It is desirable that the first center (O1) is located on the rear end side of the side frame (11), and the second center (O2) is located on the front end side of the side frame (11). Furthermore, it is desirable that the link length of the first link (71A) is longer than the link length of the second link (71B).

[0012] Incidentally, the symbols in each of the parentheses above are just examples showing the correspondence with the specific configurations etc. described in the embodiments described later, and this disclosure is not limited to the specific configurations etc. indicated by the symbols in the parentheses above. [Brief explanation of the drawing]

[0013] [Figure 1] This is a diagram showing a cushion frame according to the first embodiment. [Figure 2] This is a diagram showing a cushion frame according to the first embodiment. [Figure 3] This is a diagram showing a cushion frame according to the first embodiment. [Figure 4] This is a diagram showing the drive side changing mechanism according to the first embodiment. [Figure 5]It is a diagram showing a drive - side change mechanism according to the first embodiment. [Figure 6] It is a diagram showing a drive - side change mechanism according to the first embodiment. [Figure 7] It is a diagram showing a drive - side change mechanism according to the first embodiment. [Figure 8] It is a diagram showing a driven - side change mechanism according to the first embodiment. [Figure 9] It is a diagram showing a drive - side change mechanism according to the first embodiment. [Figure 10] It is a diagram showing the positional relationship between the cushion pad and the connection location.

Mode for Carrying Out the Invention

[0014] The following "Embodiments of the Invention" show an example of embodiments belonging to the technical scope of the present disclosure. That is, the invention - specifying matters described in the claims are not limited to the specific configurations, structures, etc. shown in the following embodiments.

[0015] This embodiment is an example in which the seat according to the present disclosure is applied to a seat (hereinafter referred to as a vehicle seat) mounted on a vehicle such as a car. Arrows, slashes, etc. indicating directions attached to each figure are described to facilitate understanding of the relationships between the figures and the shapes of members or parts.

[0016] Therefore, the vehicle seat is not limited to the directions attached to each figure. The directions shown in each figure are the directions in the state where the vehicle seat according to this embodiment is assembled to the vehicle. The figure with slashes does not always show a cross - sectional view.

[0017] At least the members or parts described with reference numerals are provided with at least one, unless otherwise stated such as "one". The seat shown in the present disclosure includes at least one of the components such as the members or parts described with reference numerals and the structural parts shown in the drawings.

[0018] (First Embodiment) <1. Overview of Vehicle Seats> As shown in Figure 1, the vehicle seat 1 includes at least a seat cushion 3, a seat back (not shown), a lifter mechanism 5, and a posture adjustment mechanism 7. The seat cushion 3 is the part that supports the buttocks of the person sitting.

[0019] The seatback is the part that supports the back of the seated person. The seatback is connected to the rear end of the seat cushion 3. The seatback is connected to the seat cushion 3 so that it can swing in the front-to-back direction of the seat.

[0020] The lifter mechanism 5 is a mechanism that moves the entire seat cushion 3 in a parallel manner, causing the seat cushion 3 to move up and down. The posture changing mechanism 7 is a mechanism that changes the posture of the seat cushion 3 between a comfortable posture and a normal posture.

[0021] The comfortable posture is a posture in which the front end of the seat cushion 3 is higher than the rear end of the seat cushion 3, as shown in Figure 2. The normal posture is a posture in which the height difference between the front end of the seat cushion 3 and the rear end of the seat cushion 3 is smaller than that of the comfortable posture, as shown in Figure 1.

[0022] In other words, the normal posture is primarily the posture in which the vehicle driver operates the vehicle. The lifter mechanism 5 according to this embodiment raises and lowers the seat cushion 3 in the normal posture state.

[0023] The seat cushion 3 is connected to the sliding device 9 via the lifter mechanism 5 and the posture change mechanism 7. When the lifter mechanism 5 is in operation, the posture change mechanism 7 functions as a lifter link for the lifter mechanism 5.

[0024] The lifter mechanism 5 includes lifter links 5A and 5B (see Figure 3). Lifter links 5A and 5B are links for raising and lowering the rear end of the seat cushion 3. When the lifter mechanism 5 is in operation, the posture change mechanism 7 functions as a lifter link for raising and lowering the front end of the seat cushion 3.

[0025] The sliding device 9 supports the seat cushion 3 so that it can be displaced in the front-rear direction. In this embodiment, the seat cushion 3 is supported by two sliding devices 9. Each sliding device 9 has at least a movable rail 9A and a fixed rail 9B, etc.

[0026] Each fixed rail 9B is a rail member fixed to the vehicle. The movable rail 9A is an example of a base member and is slidably connected to the fixed rail 9B. Therefore, the seat cushion 3 can slide relative to the vehicle.

[0027] <2. Configuration of the cushion frame and posture change mechanism, etc.> <2.1 Composition of the cushion frame> The cushion frame 10 is a structural member that constitutes the skeleton of the seat cushion 3. As shown in Figure 1, the cushion frame 10 includes at least a first side frame 11, a second side frame 12, a front rod member 13, and a rear rod member 14.

[0028] The first side frame 11 is a lower arm positioned at one end in the seat width direction and extending in the seat front-rear direction. The second side frame 12 is a lower arm positioned at the other end in the seat width direction and extending in the seat rearward direction.

[0029] The front rod member 13 extends in the width direction of the seat and connects the front end of the first side frame 11 and the front end of the second side frame 12, and is rotatably connected to each of the side frames 11 and 12.

[0030] The rear rod member 14 extends in the seat width direction and connects to the rear end of the first side frame 11 and the rear end of the second side frame 12, and is rotatably connected to each side frame 11 and 12. The upper ends of the lifter links 5A and 5B are integrated with the rear rod member 14 by joining methods such as welding.

[0031] The lower ends of the lifter links 5A and 5B are rotatably connected to the corresponding movable rails 9A via brackets 5C and 5D, as shown in Figure 3. In other words, the rear end of the cushion frame 10 is indirectly rotatably connected to the movable rails 9A via the lifter links 5A and 5B.

[0032] In other words, the lifter link 5A and bracket 5C function as connecting parts that indirectly and rotatably connect the rear end of the first side frame 11 to the movable rail 9A. The lifter link 5B and bracket 5D function as connecting parts that indirectly and rotatably connect the rear end of the second side frame 12 to the movable rail 9A.

[0033] An actuator 5E (see Figure 3) is provided on the first side frame 11 or the second side frame 12 (in this embodiment, the first side frame 11). The actuator 5E exerts a driving force to rotate the rear rod member 14.

[0034] As a result, when the actuator 5E is activated and the rear rod member 14 rotates, the lifter links 5A and 5B are rotationally displaced relative to the cushion frame 10, and the cushion frame 10 is displaced vertically in conjunction with this rotational displacement.

[0035] <2.2 Configuration of the attitude change mechanism> As shown in Figure 3, the posture changing mechanism 7 is configured to include a drive-side changing mechanism 71 and a driven-side changing mechanism 72, etc. The drive-side changing mechanism 71 exerts a driving force to change the posture of the seat cushion 3. The driven-side changing mechanism 72 receives a driving force from the drive-side changing mechanism 71 and works in cooperation with the drive-side changing mechanism 71 to change the posture of the seat cushion 3.

[0036] <2.3 Configuration of the drive side change mechanism> The drive side changing mechanism 71, as shown in Figure 4, includes at least a first drive side link 71A, a second drive side link 71B, a sector gear 71C, and an actuator 71D. The lower end of the first drive side link 71A is rotatably connected to the movable rail 9A via a bracket 71E, as shown in Figure 5.

[0037] The lower end of the second drive link 71B is rotatably connected to the upper end of the first drive link 71A. The upper end of the second drive link 71B is rotatably connected to the first side frame 11.

[0038] Specifically, the upper end of the second drive-side link 71B is integrally fixed to the front rod material 13 by welding or the like, and the front rod material 13 is rotatably connected to the first side frame 11. Therefore, the upper end of the second drive-side link 71B is configured to be rotatably connected to the first side frame 11.

[0039] The connection point J1 between the first drive-side link 71A and the second drive-side link 71B is located between the sector gear 71C and the first side frame 11, as shown in Figure 6. In this embodiment, the connection point J1 is located at a point spaced apart from the sector gear 71C towards the first side frame 11.

[0040] The second drive-side link 71B is located between the first drive-side link 71A and the first side frame 11. In other words, the second drive-side link 71B is located on the first side frame 11 side relative to the first drive-side link 71A.

[0041] Incidentally, in this embodiment, as shown in Figure 5, the link length Lk1 of the first drive-side link 71A is longer than the link length Lk2 of the second drive-side link 71B. Furthermore, the connection center between the first drive-side link 71A and the movable rail 9A is located forward of the center O2 of the front rod member 13.

[0042] As shown in Figure 6, the sector gear 71C is integrally fixed to the front rod material 13 by welding or the like. Therefore, when the sector gear 71C rotates, the front rod material 13 rotates, causing the second drive-side link 71B to rotate around axis L1.

[0043] Note that axis L1 is the central axis of the front rod material 13. The rotation center of the sector gear 71C is located on axis L1. In other words, both the rotation center of the sector gear 71C and the rotation center of the connection between the second drive side link 71B and the first side frame 11 are located on axis L1.

[0044] In this embodiment, the rotation center of the sector gear 71C and the rotation center connecting the second drive-side link 71B and the first side frame 11 are spaced apart from each other in the direction of axis L1. Therefore, the front rod member 13 functions as a transmission unit that transmits the rotation of the sector gear 71C to the second drive-side link 71B.

[0045] The actuator 71D exerts a driving force to rotate the sector gear 71C. The actuator 71D is composed of an electric motor (not shown) and a reduction gear (not shown), etc.

[0046] The electric motor outputs rotational force. The reduction gear is a gear system having at least a worm and a worm wheel, which reduces the output of the electric motor before outputting it. The actuator 71D is fixed to the first drive-side link 71A.

[0047] Incidentally, since actuator 71D has an electric motor and a reduction gear, it is practically impossible to rotate the electric motor by applying an external rotational force to the output shaft of the reduction gear. Hereafter, this will be referred to as the "self-locking function".

[0048] Furthermore, the connection point between the first drive link 71A and the second drive link 71B (hereinafter referred to as the moving center Om) is located behind the second center O2, as shown in Figure 7. In addition, in the normal orientation, the moving center Om is located higher than the center line Lc.

[0049] The center line Lc refers to a virtual line extending in the front-rear direction of the seat, passing through the first center O1 and the second center O2. The first center O1 refers to the connection center between the lifter link 5A and the first side frame 11.

[0050] The second center O2 refers to the connection center between the second drive-side link 71B and the first side frame 11. In this embodiment, the first center O1 is located on the central axis of the rear rod member 14. In this embodiment, the second center O2 is located on the central axis of the front rod member 13.

[0051] <2.4 Configuration of the Driven Side Change Mechanism> As shown in Figure 8, the driven-side changing mechanism 72 includes at least a first driven-side link 72A and a second driven-side link 72B. The first driven-side link 72A is the link corresponding to the first drive-side link 71A. The second driven-side link 72B is the link corresponding to the second drive-side link 71B.

[0052] Specifically, the lower end of the first driven link 72A is rotatably connected to the movable rail 9A. The lower end of the second driven link 72B is rotatably connected to the upper end of the first driven link 72A. The upper end of the second driven link 72B is rotatably connected to the second side frame 12 via the front rod member 13.

[0053] Furthermore, the driven-side changing mechanism 72 is not equipped with a drive mechanism such as a sector gear or actuator. In other words, the driving force of the actuator 71D is transmitted to the driven-side changing mechanism 72, that is, the second driven-side link 72B and the first driven-side link 72A, via the front rod member 13.

[0054] <3. Operation of the posture change mechanism and features of the vehicle seat according to this embodiment> <3.1 Operation of the posture change mechanism> When actuator 71D is stopped, the self-locking function maintains the angle θ1 between the first drive-side link 71A and the second drive-side link 71B (see Figure 5), and the angle θ2 between the first driven-side link 72A and the second driven-side link 72B (see Figure 8) in their current state.

[0055] Therefore, when the actuator 5E of the lifter mechanism 5 is activated while the actuator 71D is stopped, the lifter links 5A and 5B swing and displace relative to the movable rail 9A while angles θ1 and θ2 remain constant, causing the entire seat cushion 3 to move up and down in a parallel motion.

[0056] Furthermore, when the actuator 71D of the posture change mechanism 7 is activated while the actuator 5E of the lifter mechanism 5 is stopped, angles θ1 and θ2 increase or decrease, causing the front end of the seat cushion 3 to move up or down relative to the rear end of the seat cushion 3.

[0057] <3.2 Characteristics of vehicle seats> As shown in Figure 9, when a large external force Fo acts on the first side frame 11, pulling the entire first side frame to the rear, a force F1 acts on the second center O2, that is, the front rod member 13, reducing the angle θ1 between the first drive link 71A and the second drive link 71B.

[0058] Furthermore, when an external force Fo acts on the second side frame 12, a force F1 acts on the front rod member 13, similar to the first side frame 11, such that the angle θ2 between the first driven link 72A and the second driven link 72B is reduced.

[0059] Therefore, in the vehicle seat 1 according to this embodiment, when the above-mentioned external force Fo acts on the first side frame 11 and the second side frame 12, a force is generated on the seat cushion 3 that causes the front end of the seat cushion 3 to fall downward. Thus, it is possible to suppress the unintended upward displacement of the front end of the seat cushion 3.

[0060] As shown in Figure 6, the connection point J1 between the first drive-side link 71A and the second drive-side link 71B is located between the sector gear 71C and the first side frame 11. As a result, in the vehicle seat 1, as shown in Figure 10, the connection point J1 is offset outward in the seat width direction relative to the cushion pad 3A of the seat cushion 3.

[0061] Therefore, interference between the posture changing mechanism 7 and the lower surface of the cushion pad 3A can be suppressed (see part A in Figure 10). Consequently, since there is no need to provide a cover or the like to cover the upper side of the posture changing mechanism 7, the increase in the manufacturing cost of the vehicle seat 1 can be suppressed.

[0062] Incidentally, in this embodiment, because the outer diameter of the sector gear 71C is large, if the position of the sector gear 71C is shifted outward in the seat width direction from the position shown in Figure 6, the sector gear 71C and the sliding device 9 will interfere with each other.

[0063] (Other embodiments) In the embodiments described above, the center of movement Om was located higher than the centerline Lc in the normal orientation. However, this disclosure is not limited to this. That is, in the disclosure, for example, the center of movement Om may be at the same height as the centerline Lc in the normal orientation.

[0064] In the above-described embodiment, the posture changing mechanism 7 was positioned on the front end of the seat cushion 3. However, this disclosure is not limited to this. That is, the disclosure may also include, for example, a configuration in which the posture changing mechanism 7 is positioned on the rear end of the seat cushion 3, or a configuration in which the posture changing mechanism 7 is positioned on both the front and rear ends of the seat cushion 3.

[0065] In the above-described embodiment, the link length Lk1 of the first drive-side link 71A was longer than the link length Lk2 of the second drive-side link 71B. However, the disclosure is not limited thereto. That is, the disclosure may also include, for example, a configuration in which the link length Lk1 is shorter than the link length Lk2, or a configuration in which the link lengths Lk1 and Lk2 are the same.

[0066] In the above-described embodiment, the system was configured to include a lifter mechanism 5. However, this disclosure is not limited thereto. That is, the disclosure may also include, for example, a configuration in which the lifter mechanism 5 is eliminated. In this configuration, the first side frame 11 and the second side frame 12 are directly and rotatably connected to the movable rail 9A without the need for lifter links 5A and 5B.

[0067] In the above-described embodiment, the vehicle seat 1 was fixed to the vehicle floor via a sliding device 9. However, the disclosure is not limited thereto. That is, the disclosure may also include a configuration in which the vehicle seat 1 is directly fixed to the vehicle floor without the use of a sliding device 9.

[0068] In the embodiments described above, the vehicle seat according to this disclosure was applied to a vehicle. However, the application of the invention disclosed herein is not limited to this. That is, the disclosure can be applied, for example, to seats used in vehicles such as railway cars, ships and aircraft, as well as to stationary seats used in theaters, homes, etc.

[0069] Furthermore, this disclosure is not limited to the embodiments described above, but is sufficient to be consistent with the intent of the disclosures described in the embodiments described above. Therefore, it may be a configuration in which at least two of the embodiments described above are combined, or a configuration in which any of the illustrated components or components described with reference numerals in the embodiments described above are omitted. [Explanation of Symbols]

[0070] 1… Vehicle seats 3… Seat cushion 3A… Cushion pad 5… Lifter mechanism 7… Attitude change mechanism 9… Slide device 10… Cushion frame 11… First side frame 12… Second side frame 13… Front rod material 14… Rear rod material 71… Drive side change mechanism 71A… First drive side link 71B… Second drive link 71C… Sector gear 71E… Bracket 71D… Actuator 72… Driven side change mechanism 72A… First driven link 72B… Second driven link J1… Connection point

Claims

1. In a seat in which one end of the seat cushion can be moved up and down in the front-to-back direction, A side frame extending in the front-rear direction of the seat and constituting a part of the cushion frame, the side frame having a connecting portion that is directly or indirectly rotatably connected to the base member at the other end in the extension direction, A posture changing mechanism having a first link and a second link for connecting the other end of the side frame in the extension direction to the base member, comprising a posture changing mechanism that causes one end of the seat cushion in the front-rear direction to be raised or lowered by changing the angle between the first link and the second link, The lower end of the first link is rotatably connected to the base member, The lower end of the second link is rotatably connected to the upper end of the first link. The upper end of the second link is rotatably connected to the side frame, The connection point of the aforementioned connecting portion with the side frame is designated as the first center, and the connection point of the second link with the side frame is designated as the second center. When a virtual line extending in the front-rear direction through the first center and the second center is defined as the centerline, and the connection center between the first link and the second link is defined as the center of movement, The aforementioned center of movement is located behind the second center, Furthermore, in the normal position where at least one end of the seat cushion in the front-rear direction is lowered, the center of movement is at the same height as the center line, or higher than the center line.

2. The connecting portion is connected to the base member via a lifter link, the lower end of which is rotatably connected to the base member, and the upper end of which is rotatably connected to the side frame at the first center. Furthermore, the seat according to claim 1, wherein the entire seat cushion is displaced vertically as the lifter link swings relative to the base member while the angle between the first link and the second link is constant.

3. The seat according to claim 2, wherein the first center is located on the rear end side of the side frame, and the second center is located on the front end side of the side frame.

4. The sheet according to any one of claims 1 to 3, wherein the link length of the first link is longer than the link length of the second link.

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