seat
The seat design addresses interference issues by using a side frame and sector gear mechanism to lift and lower the seat cushion, reducing manufacturing costs and ensuring smooth operation without additional covers.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2026-03-13
AI Technical Summary
The existing posture-changing mechanism in vehicle seats is disposed directly below the seat cushion, risking interference with the cushion and increasing manufacturing costs due to the need for additional covers.
A seat design that allows one end side of the seat cushion to lift and lower in the front-rear direction, utilizing a side frame, links, and a sector gear mechanism to prevent interference by offsetting the connection points, thereby eliminating the need for additional covers.
Suppresses interference between the posture-changing mechanism and the seat cushion, reducing manufacturing costs by avoiding the need for extra coverings and ensuring smooth operation.
Smart Images

Figure 2026046358000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a seat capable of lifting and lowering 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 for lifting and lowering 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] The posture - changing mechanism described in Patent Document 1 is disposed directly below the seat cushion. Therefore, there is a risk that the posture - changing mechanism may interfere with a part of the seat cushion (for example, the lower surface of the cushion pad). The present disclosure discloses an example of a seat in view of the above points.
Means for Solving the Problems
[0005] A seat capable of lifting and lowering one end side in the front - rear direction of a seat cushion (3) preferably includes at least one of the following constituent elements. 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 (7) having a first link (71A), a second link (71B), and a sector gear (71C) that rotates under the influence of a driving force for connecting one end of the side frame (11) in the extension direction to the base member (9A), and the posture changing mechanism (7) that causes the angle between the first link (71A) and the second link (71B) to change as the sector gear (71C) rotates, thereby causing one end of the seat cushion (3) in the front-rear direction to move up and down.
[0006] Furthermore, the longitudinal lower end of the first link (71A) is rotatably connected to the base member (9A), the longitudinal lower end of the second link (71B) is rotatably connected to the longitudinal upper end of the first link (71A), and the longitudinal upper end of the second link (71B) is rotatably connected to the side frame (11), and it is desirable that the connection point (J1) between the first link (71A) and the second link (71B) is located between the sector gear (71C) and the side frame (11).
[0007] As a result, in this seat, the connection point (J1) between the first link (71A) and the second link (71B) is offset outward in the seat width direction relative to, for example, the cushion pad of the seat cushion. Therefore, interference between the posture changing mechanism and a part of the seat cushion (for example, the underside of the cushion pad) can be suppressed. Consequently, since there is no need to provide a cover or the like to cover the upper side of the posture changing mechanism, an increase in the manufacturing cost of the seat can be suppressed.
[0008] The sheet may also have the following configuration, for example. It is desirable that the second link (71B) be positioned between the first link (71A) and the side frame (11).
[0009] Furthermore, it is desirable that the rotation center of the sector gear (71C) and the connecting rotation center of the second link (71B) and the side frame (11) lie on the same axis, and that the rotation center and the connecting rotation center are spaced apart in the axial direction, and that a transmission unit (13) is provided to transmit the rotation of the sector gear (71C) to the second link (71B).
[0010] Furthermore, when the connection center between the connecting parts (5A, 5C) and the side frame (11) is defined as the first center (O1), the connection center between the second link (71B) and the side frame (11) is defined as the second center (O2), the imaginary line extending in the front-rear direction through the first center (O1) and the second center (O2) is defined as the centerline (Lc), and the connection center between the first link (71A) and the second link (71B) is defined as the movement center (Om), then the movement center (Om) is located behind the second center (O2), and furthermore, it is desirable that the movement center (Om) is at the same height as the centerline (Lc) or higher than the centerline (Lc), regardless of the state of the attitude change mechanism (7).
[0011] 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]
[0012] [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] This is a diagram showing the drive side changing mechanism according to the first embodiment. [Figure 6] This is a diagram showing the drive side changing 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 point. [Figure 11] It is a diagram showing a drive-side change mechanism according to the second embodiment.
Mode for Carrying Out the Invention
[0013] The following "Embodiments of the Invention" show an example of embodiments belonging to the technical scope of the present disclosure. That is, the invention-specific matters described in the claims are not limited to the specific configurations, structures, etc. shown in the following embodiments.
[0014] 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. The arrows, slashes, etc. indicating the directions attached to each figure are described to facilitate understanding of the relationships between the figures and the shapes of members or parts.
[0015] 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.
[0016] 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.
[0017] (First Embodiment) <1. Outline of Vehicle Seat> As shown in FIG. 1, the vehicle seat 1 includes at least a seat cushion 3, a seat back (not shown), a lifter mechanism 5, a posture changing mechanism 7, and the like. The seat cushion 3 is a part for supporting the buttocks of the seated person.
[0018] The seat back is a part for supporting the back of the seated person. The seat back is connected to the rear end side of the seat cushion 3. The seat back is connected to the seat cushion 3 so as to be swingable in the front-rear direction of the seat.
[0019] The lifter mechanism 5 is a mechanism for lifting and lowering the seat cushion 3 so as to move the entire seat cushion 3 in parallel. The posture changing mechanism 7 is a mechanism for displacing the posture of the seat cushion 3 between a comfortable posture and a normal posture.
[0020] As shown in FIG. 2, the comfortable posture is a posture in which the front end side of the seat cushion 3 is at a higher position than the rear end side of the seat cushion 3. The normal posture is a posture in which the height difference between the front end side of the seat cushion 3 and the rear end side of the seat cushion 3 is smaller than that in the comfortable posture, as shown in FIG. 1.
[0021] That is, the normal posture is mainly a posture for the driver of the vehicle to drive the vehicle. The lifter mechanism 5 according to the present embodiment lifts and lowers the seat cushion 3 in the normal posture state.
[0022] The seat cushion 3 is connected to the slide device 9 via the lifter mechanism 5 and the posture changing mechanism 7. When the lifter mechanism 5 operates, the posture changing mechanism 7 functions as a lifter link of the lifter mechanism 5.
[0023] 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.
[0024] 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.
[0025] 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.
[0026] <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.
[0027] 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.
[0028] 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.
[0029] 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.
[0030] 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.
[0031] 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.
[0032] 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.
[0033] 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.
[0034] <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.
[0035] <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.
[0036] 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.
[0037] 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.
[0038] 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.
[0039] 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.
[0040] 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.
[0041] 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.
[0042] 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.
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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".
[0047] 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.
[0048] 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.
[0049] 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.
[0050] <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.
[0051] 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.
[0052] 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.
[0053] <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.
[0054] 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.
[0055] 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.
[0056] <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.
[0057] 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.
[0058] 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.
[0059] 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.
[0060] 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.
[0061] 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.
[0062] (Second Embodiment) In the above-described embodiment, the second drive-side link 71B was connected to the sector gear 71C via the front rod member 13. In contrast, in this embodiment, as shown in Figure 11, the second drive-side link 71B is integrated with the sector gear 71C, and the integrated second drive-side link 71B is rotatably connected to the first drive-side link 71A.
[0063] Furthermore, a stepped portion 71F is formed at the connection between the sector gear 71C and the second drive-side link 71B. As a result, the second drive-side link 71B is offset outward in the seat width direction from the sector gear 71C, that is, towards the first side frame 11.
[0064] Therefore, in this embodiment as well, 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.
[0065] (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.
[0066] 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.
[0067] 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.
[0068] 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.
[0069] 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.
[0070] 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.
[0071] 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]
[0072] 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 comprising a first link, a second link, and a sector gear that rotates under driving force for connecting one end of the side frame in the extension direction to the base member, wherein the rotation of the sector gear changes the angle between the first link and the second link, thereby causing one end of the seat cushion in the front-rear direction to be raised or lowered. The longitudinal lower end of the first link is rotatably connected to the base member, The longitudinal lower end of the second link is rotatably connected to the longitudinal upper end of the first link. The upper longitudinal end of the second link is rotatably connected to the side frame, A seat in which the connection point between the first link and the second link is located between the sector gear and the side frame.
2. The seat according to claim 1, wherein the second link is positioned between the first link and the side frame.
3. The rotation center of the sector gear and the connecting rotation center of the second link and the side frame are located on the same axis, and the rotation center and the connecting rotation center are spaced apart in the axial direction. Furthermore, the seat according to claim 2, further comprising a transmission unit for transmitting the rotation of the sector gear to the second link.
4. 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, according to any one of claims 1 to 3.
Citation Information
Patent Citations
Seat frame mechanism with adjustable inclination angle
CN216268818U