Vehicle seat frame and vehicle seat

Abstract

To obtain a vehicle seat frame in which rising force and rising speed of a back frame can be finely adjusted according to a reclining angle of the back frame.SOLUTION: A vehicle seat frame 20 includes: a cushion frame 22 forming a skeleton of a seat cushion 12; a back frame 32 forming a skeleton of a seat back 14 and connected to the cushion frame 22 so as to be reclinable; a torsion bar 46 having one end 46A engaged with one of the cushion frame 22 and the back frame 32; and a slide contact member 54 provided in the other of the cushion frame 22 and the back frame 32. When the back frame 32 is reclined, the torsion bar 46 is twisted while causing slide contact of the other end 46B.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle seat, and more particularly to a frame for a vehicle seat. [Background technology]

[0002] The automobile seat described in Patent Document 1 below includes a cushion frame that forms the framework of the seat cushion, a back frame that forms the framework of the seat back and is connected to the cushion frame so that it can be reclined, and two torsion bars, one end of which is fastened to the cushion frame and the other end of which is fastened to the back frame. The two torsion bars are twisted when the back frame is reclined, and urge the back frame in an upright direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2006 / 075532 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned prior art, one end of each torsion bar is anchored to the cushion frame, and the other end of each torsion bar is anchored to the back frame, so the biasing force (biasing torque) on the back frame increases at a constant rate in proportion to the increase in the reclining angle of the back frame, which poses a problem in that it is not possible to fine-tune the rising force and rising speed of the back frame according to the reclining angle of the back frame.

[0005] SUMMARY OF THE INVENTION In consideration of the above, the present invention aims to provide a vehicle seat frame and a vehicle seat that allow the rising force and rising speed of the back frame to be finely adjusted according to the reclining angle of the back frame. [Means for solving the problem]

[0006] The vehicle seat frame of the first aspect includes a cushion frame that forms the skeleton of a seat cushion, a back frame that forms the skeleton of a seat back and is connected to the cushion frame so that it can be reclined, a torsion bar having one end engaged with one of the cushion frame and the back frame, and a sliding contact portion that is provided on the other of the cushion frame and the back frame and whose other end is in sliding contact with the torsion bar and twisted when the back frame is reclined.

[0007] In the vehicle seat frame of the first aspect, a back frame constituting the framework of the seat back is connected to a cushion frame constituting the framework of the seat cushion so as to be able to recline. One end of a torsion bar is engaged with one of the cushion frame and the back frame. When the back frame is reclined, the other end of the torsion bar comes into sliding contact with a sliding contact portion provided on the other of the cushion frame and the back frame. This twists the torsion bar, urging the back frame in an upright direction. By changing the shape of the sliding contact portion, the upright force and upright speed of the back frame can be finely adjusted according to the reclining angle of the back frame.

[0008] In the vehicle seat frame of the second aspect, in the first aspect, the sliding contact portion is a sliding contact member made of resin and attached to the other.

[0009] According to the vehicle seat frame of the second aspect, the other end of the torsion bar comes into sliding contact with a sliding contact member attached to the other of the cushion frame and the back frame. This sliding contact member is made of resin, which makes the sliding contact smooth.

[0010] The vehicle seat frame of a third aspect is the first or second aspect, wherein the sliding contact portion has a sliding contact surface with which the other end of the torsion bar slides, the sliding contact surface being formed in an uneven shape.

[0011] According to the vehicle seat frame of the third aspect, the other end of the torsion bar is in sliding contact with the sliding surface of the sliding portion provided on the other of the cushion frame and the back frame. This sliding surface is formed with an uneven surface, so that the torsion angle of the torsion bar can be changed by adjusting the unevenness of the sliding surface. As a result, it is easy to fine-tune the rising force and rising speed of the back frame.

[0012] A fourth aspect of the vehicle seat frame is any one of the first to third aspects, wherein the back frame has a contact portion that contacts the other end of the torsion bar when the reclining angle is less than a certain value, thereby separating the other end from the sliding contact portion.

[0013] According to the vehicle seat frame of the fourth aspect, when the reclining angle of the back frame is less than a certain value, the contact portion provided on the back frame comes into contact with the other end of the torsion bar, and the other end of the torsion bar moves away from the sliding contact portion, thereby preventing the back frame from being biased in the upright direction more than necessary.

[0014] A vehicle seat frame of a fifth aspect is any one of the first to fourth aspects, in which the other end side of the torsion bar is inserted into a through hole formed in the back frame, and the torsion bar is twisted while being supported by the hole edge portion of the through hole.

[0015] According to the vehicle seat frame of the fifth aspect, a through hole through which the other end of the torsion bar is inserted is formed in the back frame, and the torsion bar is twisted while being supported by the hole edge of the through hole, thereby making it possible to stabilize the torsional deformation of the torsion bar with a simple configuration.

[0016] The vehicle seat frame of the sixth aspect is any one of the first to fifth aspects, and is provided with a spiral spring having one end engaged with the cushion frame and the other end engaged with the back frame, and which is wound up by reclining the back frame.

[0017] According to the vehicle seat frame of the sixth aspect, one end of the spiral spring is anchored to the cushion frame, and the other end of the spiral spring is anchored to the back frame. When the back frame is reclined, the spiral spring is wound tight and the torsion bar is twisted. In this way, since not only the torsion bar but also the spiral spring is provided, fine adjustment of the rising force and rising speed of the back frame is easier than when only the torsion bar is provided.

[0018] A vehicle seat of the seventh aspect comprises a seat cushion on which a vehicle occupant sits, a seat back that supports the back of the occupant, and a vehicle seat frame of any one of the first to sixth aspects, which has a cushion frame that forms the skeleton of the seat cushion and a back frame that forms the skeleton of the seat back.

[0019] In the vehicle seat of the seventh aspect, a vehicle occupant sits on a seat cushion, and the back of the occupant is supported by a seat back. This vehicle seat includes a vehicle seat frame having a cushion frame that forms the framework of the seat cushion and a back frame that forms the framework of the seat back. This vehicle seat frame is any one of the first to sixth aspects, and therefore provides the above-mentioned functions and effects. [Effects of the Invention]

[0020] As described above, in the vehicle seat frame and vehicle seat according to the present invention, the rising force and rising speed of the back frame can be finely adjusted in accordance with the reclining angle of the back frame. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a perspective view showing a configuration of a vehicle seat frame included in a vehicle seat according to an embodiment. [Figure 2] 2 is a perspective view showing a configuration around one end of a torsion bar in a vehicle seat frame according to an embodiment of the present invention; FIG. [Figure 3] 4 is a perspective view showing the configuration of the other end portion of the torsion bar and its surroundings in the vehicle seat frame according to the embodiment. FIG. [Figure 4] 4 is a perspective view showing the configuration of the other end portion of the torsion bar and its surroundings in the vehicle seat frame according to the embodiment. FIG. [Figure 5] FIG. 10 is a schematic side view for explaining the reclining range of the back frame. [Figure 6] 10 is a side view showing the configuration of the periphery of the other end of the torsion bar in the vehicle seat frame according to the embodiment, showing a state in which the other end of the torsion bar is in contact with the sliding contact member. FIG. [Figure 7] 10 is a side view showing the configuration of the other end portion of the torsion bar and its surroundings in the vehicle seat frame according to the embodiment, showing a state in which the reclining angle of the back frame is at its maximum. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0022] A vehicle seat 10 according to one embodiment of the present invention will be described below with reference to Figures 1 to 7. Note that in each figure, some reference numerals may be omitted to make the drawings easier to understand. Arrows FR, LH, RH, and UP, which are appropriately depicted in each figure, respectively indicate the front, left, right, and top of the vehicle seat 10. Hereinafter, when the front-rear, left-right, top-bottom directions are used in the description, they will indicate directions relative to the vehicle seat 10 unless otherwise specified.

[0023] 1, a vehicle seat 10 according to this embodiment includes a seat cushion 12 on which a vehicle occupant sits, and a seat back 14 that supports the back of the occupant. The vehicle seat 10 includes a vehicle seat frame 20 having a cushion frame 22 that forms the framework of the seat cushion 12 and a back frame 32 that forms the framework of the seat back 14. In addition to the cushion frame 22 and the back frame 32, the vehicle seat frame 20 includes a spiral spring 42, a torsion bar 46, and a sliding contact member 54.

[0024] The cushion frame 22 has a pair of left and right side frames 24, a front frame 26 connecting the front ends of the left and right side frames 24 in the left-right direction, a rear frame 28 connecting the rear ends of the left and right side frames 24 in the left-right direction, and a pair of left and right hinge brackets 30 fixed to the rear parts of the left and right side frames 24.

[0025] The left and right side frames 24 are elongated plate-like with the longitudinal direction being the front-to-rear direction and the plate thickness direction being the left-to-right direction. The front frame 26 is elongated plate-like with the longitudinal direction being the left-to-right direction and the plate thickness direction being the up-down direction. The rear frame 28 is tubular with the axial direction being the left-to-right direction. The left and right hinge brackets 30 are elongated plate-like with the longitudinal direction being the up-to-down direction and the plate thickness direction being the left-to-right direction. The left and right side frames 24, the front frame 26, and the left and right hinge brackets 30 are made of, for example, press-formed metal plate material, and the rear frame 28 is made of, for example, metal pipe material.

[0026] The lower portions of the left and right hinge brackets 30 are overlapped with the rear portions of the left and right side frames 24 from the outer side in the left-right direction, and are fixed to the left and right side frames 24 by means of bolts or the like. The upper portions of the left and right hinge brackets 30 protrude upward from the rear portions of the left and right side frames 24. The left and right side frames 24 and the left and right hinge brackets 30 may be configured to be integrally formed.

[0027] The back frame 32 has a pair of left and right side frames 34, an upper frame 36 connecting the upper ends of the left and right side frames 34 in the left-right direction, and a lower frame 38 connecting the lower ends of the left and right side frames 34 in the left-right direction.

[0028] The left and right side frames 34 are elongated plates with their longitudinal direction extending up and down and their thickness direction extending left and right. The upper frame 36 and the lower frame 38 are cylindrical with their axial direction extending left and right. The left and right side frames 34 are made of, for example, press-formed metal plate material, and the upper frame 36 and the lower frame 38 are made of, for example, metal pipe material.

[0029] The lower ends of the left and right side frames 34 are disposed inward in the left-right direction relative to the upper ends of the left and right hinge brackets 30, and are connected to the upper ends of the left and right hinge brackets 30 via well-known reclining mechanisms 40. This allows the back frame 32 to be reclined (tilted) relative to the cushion frame 22. When the back frame 32 is in an upright position relative to the cushion frame 22 (when the back frame 32 is in an initial lock position, which will be described later), the front-to-back, up-to-down directions of the back frame 32 (i.e., the seat back 14) substantially coincide with the front-to-back, up-to-down directions of the vehicle seat 10. Hereinafter, the front-to-back, up-to-down directions described with respect to the back frame 32 refer to the directions when the back frame 32 is in an upright position.

[0030] The spiral spring 42 is disposed on the outward side in the left-right direction of one of the left and right hinge brackets 30 (here, the right hinge bracket 30) of the cushion frame 22. One end of this spiral spring 42 is secured to the hinge bracket 30, i.e., the cushion frame 22, and the other end is secured to the back frame 32. This spiral spring 42 is wound and tightened when the back frame 32 is reclined, and urges the back frame 32 in the upright direction.

[0031] The torsion bar 46 has an elongated shape with its axis extending in the left-right direction, and is disposed rearward of the lower frame 38 of the back frame 32. As shown in Figures 1 and 2, a locking bracket 48 is fixed to a middle portion of the lower frame 38 in the left-right direction. The locking bracket 48 is formed, for example, from a press-formed metal plate, and is disposed rearward of the lower frame 38.

[0032] The locking bracket 48 has left and right sidewalls 48A (the right sidewall 48A is not shown) that face each other in the left-right direction, a rear wall 48B that connects the rear ends of the left and right sidewalls 48A in the left-right direction, and left and right flanges 48C (the right flange 48C is not shown) that extend outward in the left-right direction from the front ends of the left and right sidewalls 48A. The left and right flanges 48C are fixed to the lower frame 38 by welding or other means. An elongated hole 50 is formed in the sidewall 48A on the left side of the seat. The elongated hole 50 has its longitudinal direction in the up-down direction and penetrates the left sidewall 48A in the left-right direction. One end 46A of the torsion bar 46 (the right end here) is inserted into the elongated hole 50. The one end 46A of the torsion bar 46 is bent into a U-shape and fitted into the elongated hole 50. As a result, one end 46A of the torsion bar 46 is locked to the back frame 32.

[0033] As shown in FIG. 3 , the other end of the torsion bar 46 is inserted into a through-hole 52 formed in the lower end of the left side frame 34. This through-hole 52 penetrates the left side frame 34 in the left-right direction, and the other end 46B of the torsion bar 46 is located on the left side (outer side in the left-right direction) of the left side frame 34. The other end 46B of the torsion bar 46 is bent downward at a first bent portion 46B1 located near the through-hole 52 and is bent at a second bent portion 46B2 located in the middle in the up-down direction into a generally V-shape that convex forward. The front surface of this second bent portion 46B2 is curved in an arc shape that convex forward when viewed left-right. The other end 46B of the torsion bar 46 corresponds to the sliding contact member 54.

[0034] The sliding contact member 54 is disposed between the other end 46B of the torsion bar 46 and the left hinge bracket 30 and is attached to the left hinge bracket 30. The sliding contact member 54 is manufactured, for example, by injection molding and is made of resin. Examples of resins that may be used to form the sliding contact member 54 include polyacetal (POM), nylon 6 (PA6), and acrylonitrile-butadiene-styrene copolymer (ABS). As shown in FIGS. 3 and 4 , the sliding contact member 54 has a main body 54A disposed on the rear side of the upper part of the hinge bracket 30 and a fixing piece 54B extending forward from the outer end (here, the left end) of the main body 54A in the left-right direction. The fixing piece 54B is fixed to the hinge bracket 30 using, for example, a screw 56.

[0035] The rear surface of the main body 54A serves as a sliding surface 58 against which the other end 46B of the torsion bar 46 slides when the back frame 32 is reclined. As an example, this sliding surface 58 is formed in an uneven shape, with a vertically intermediate portion serving as a protruding portion 58A that protrudes rearward. A plurality of ribs 54C that protrude forward are formed vertically aligned on the front surface of the main body 54A. This allows the thickness of the main body 54A, which has the uneven sliding surface 58, to be constant or approximately constant in the front-to-rear direction. The shape of the sliding surface 58 can be changed as needed depending on the weight of the seat back 14, the presence or absence of a spiral spring 42, and other factors. The sliding surface 58 may also be flat.

[0036] The back frame 32 has a shoulder bolt 60 as a contact portion that comes into contact with the other end 46B of the torsion bar 46 when the reclining angle is less than a certain value. The male thread portion of this shoulder bolt 60 is inserted from the left side into a through-hole (not shown) formed in the lower end of the left side frame 34 and is screwed into a nut (not shown). When the reclining angle of the back frame 32 is less than a certain value, the shoulder bolt 60 comes into contact with the other end 46B of the torsion bar 46, and the other end 46B of the torsion bar 46 is separated from the sliding surface 58 of the sliding member 54. The torsion bar 46 is slightly twisted even when the other end 46B is in contact with the shoulder bolt 60. This prevents the torsion bar 46 from rattling relative to the back frame 32.

[0037] In this embodiment, the back frame 32 is reclined (tiltable) relative to the cushion frame 22 between a front-most position designated by reference numeral 32(P1) in FIG. 5 and a rear-most position designated by reference numeral 32(P5). At the first-stage lock position designated by reference numeral 32(P2) in FIG. 5, the reclining of the back frame 32 is restricted by the first lock of the reclining mechanism 40. Reclining of the back frame 32 can be restricted in multiple stages toward the rear-most position from the first-stage lock position. The neutral position designated by reference numeral 32(P3) in FIG. 5 is a reference position in the design of the back frame 32. At the torsion bar contact position designated by reference numeral 32(P4) in FIG. 5, the other end 46B of the torsion bar 46 is configured to contact the sliding surface 58 of the sliding member 54. This torsion bar contact position is, for example, set near the center between the front-most position and the rear-most position.

[0038] The reclining angle θ of the back frame 32 at the torsion bar contact position is, for example, 60 degrees, assuming that the reclining angle of the back frame 32 at the front most position is 0 degrees. That is, in the present embodiment, as an example, when the reclining angle of the back frame 32 is less than 60 degrees, the other end 46B of the torsion bar 46 contacts the stepped bolt 60 and the other end 46B of the torsion bar 46 is separated from the sliding contact surface 58 of the sliding contact member 54. When the reclining angle of the back frame 32 is 60 degrees, the other end 46B of the torsion bar 46 contacts both the stepped bolt 60 and the sliding contact member 54. When the reclining angle of the back frame 32 exceeds 60 degrees, the other end 46B of the torsion bar 46 is separated from the stepped bolt 60 and contacts only the sliding contact surface 58 of the sliding contact member 54. The reclining angle of the back frame 32 at the torsion bar contact position is not limited to 60 degrees and can be changed as appropriate.

[0039] The other end 46B of the torsion bar 46 comes into sliding contact with the sliding contact surface 58 as the back frame 32 reclines (tilts) when the reclining angle exceeds 60 degrees. The torsion bar 46 is twisted in accordance with this sliding contact, thereby urging the back frame 32 in the upright direction. At this time, the torsion bar 46 is twisted while being supported by the edge of the through-hole 52 formed in the side frame 34.

[0040] In this embodiment, as an example, when the back frame 32 is positioned at the torsion bar contact position, a portion of the other end 46B of the torsion bar 46 below the second bent portion 46B2 comes into contact with an upper portion of the convex portion 58A on the sliding surface 58, as shown in Fig. 6. Also, in this embodiment, as an example, when the back frame 32 is reclined to the rearmost position, a portion of the other end 46B of the torsion bar 46 below the second bent portion 46B2 comes into contact with a lower portion of the convex portion 58A on the sliding surface 58, as shown in Fig. 7. In other words, when the back frame 32 is reclined from the torsion bar contact position to the rearmost position, the portion of the other end 46B of the torsion bar 46 below the second bent portion 46B2 rides over the convex portion 58A on the sliding surface 58.

[0041] (Action and effect) Next, the operation and effects of this embodiment will be described.

[0042] In this embodiment, the back frame 32 that forms the framework of the seat back 14 is connected to the cushion frame 22 that forms the framework of the seat cushion 12 so as to be able to recline. One end of a torsion bar 46 is engaged with the back frame 32. The other end of the torsion bar 46 comes into sliding contact with a sliding contact member 54 provided on the cushion frame 22 as the back frame 32 is reclined. This twists the torsion bar 46, urging the back frame 32 in an upright direction. By changing the shape of the sliding contact member 54, the rising force and rising speed of the back frame 32 can be finely adjusted according to the reclining angle of the back frame 32. As a result, for example, the seat back 14 can be adjusted to rise gently regardless of the reclining angle of the seat back 14.

[0043] In addition, in this embodiment, the sliding contact member 54 is made of resin, which allows smooth sliding contact between the other end 46B of the torsion bar 46 and the sliding contact member 54. Moreover, the sliding contact surface 58 of the sliding contact member 54 is formed with an uneven surface, which allows the torsion angle of the torsion bar 46 to be changed by the unevenness of the sliding contact surface 58. As a result, it becomes easy to fine-tune the rising force and rising speed of the back frame 32.

[0044] Furthermore, according to this embodiment, when the reclining angle of the back frame 32 is less than a certain value, the shoulder bolt 60 provided on the back frame 32 comes into contact with the other end 46B of the torsion bar 46, and the other end 46B of the torsion bar 46 moves away from the sliding contact member 54. This prevents the back frame 32 from being biased in the upright direction more than necessary.

[0045] Furthermore, according to this embodiment, the back frame 32 is formed with a through-hole 52 through which the other end of the torsion bar 46 is inserted, and the torsion bar 46 is twisted while being supported by the edge of the through-hole 52. This makes it possible to stabilize the torsional deformation of the torsion bar 46 with a simple configuration.

[0046] Furthermore, according to this embodiment, one end of the spiral spring 42 is anchored to the cushion frame 22, and the other end of the spiral spring 42 is anchored to the back frame 32. When the back frame 32 is reclined, the spiral spring 42 is wound up and the torsion bar 46 is twisted. In this way, since the spiral spring 42 is provided in addition to the torsion bar 46, fine adjustment of the rising force and rising speed of the back frame 32 is easier than when only the torsion bar 46 is provided.

[0047] In the above embodiment, the vehicle seat frame 20 is configured to include the spiral spring 42, but this is not limiting and the vehicle seat frame 20 may be configured without including the spiral spring 42. In addition, in the above embodiment, the vehicle seat frame 20 is configured to include one torsion bar 46 and one sliding contact member 54, but this is not limiting and the vehicle seat frame 20 may be configured to include a plurality of torsion bars 46 and a plurality of sliding contact members 54.

[0048] In the above embodiment, the other end of the torsion bar 46 is inserted into the through-hole 52 formed in the side frame 34 (i.e., the back frame 32), but the present invention is not limited to this. For example, the other end of the torsion bar may be inserted into a notch formed in the back frame, and the opening of the notch may be closed with a separate member. Alternatively, for example, a separate member that rotatably supports the other end of the torsion bar may be attached to the back frame.

[0049] In the above embodiment, the shoulder bolts 60 attached to the side frames 34 (i.e., the back frame 32) serve as the contact portions, but this is not limitative. The contact portions may be, for example, protrusions formed integrally with the back frame, or protrusions welded to the back frame.

[0050] In the above embodiment, the sliding contact member 54 is made of resin, but this is not limiting. For example, the sliding contact member may be made of metal and resin. Furthermore, for example, all or part of the sliding contact member may be made of soft metal.

[0051] In the above embodiment, the sliding member 54 attached to the hinge bracket 30, which is part of the cushion frame 22, is configured as the sliding part, but this is not limitative. For example, if the cushion frame is made of fiber-reinforced resin, a part of the cushion frame may be configured as the sliding part.

[0052] In the above embodiment, one end 46A of the torsion bar 46 is engaged with the back frame 32, and the other end 46B of the torsion bar 46 is in sliding contact with the sliding contact member 54 provided on the cushion frame 22, but the present invention is not limited to this. It may also be configured such that one end of the torsion bar is engaged with the cushion frame, and the other end of the torsion bar is in sliding contact with a sliding portion provided on the back frame.

[0053] In addition, the present invention can be implemented with various modifications within the scope of the gist thereof. Furthermore, it goes without saying that the scope of the rights of the present invention is not limited to the above-described embodiment. [Explanation of symbols]

[0054] 10 Vehicle seats 12 seat cushions 14 Seat back 20. Vehicle seat frame 22 Cushion Frame 32 Back Frame 42 Spiral Spring 46 Torsion bar 46A One end 46B Other end 52 Through hole 54 Sliding contact member 58 Sliding surface 60 shoulder bolt (contact part)

Claims

1. A cushion frame that forms the framework of the seat cushion, a back frame that forms a framework of the seat back and is recliningly connected to the cushion frame; a torsion bar having one end engaged with one of the cushion frame and the back frame; a sliding contact portion provided on the other of the cushion frame and the back frame, with which the torsion bar is twisted while slidingly contacting the other end portion thereof when the back frame is reclined; Equipped with The back frame has a contact portion that comes into contact with the other end of the torsion bar when the reclining angle is less than a certain value, thereby separating the other end from the sliding contact portion.

2. 2. The vehicle seat frame according to claim 1, wherein the sliding contact portion is a sliding contact member made of resin and attached to the other.

3. 3. The vehicle seat frame according to claim 1, wherein the sliding contact portion has a sliding contact surface with which the other end of the torsion bar slides, the sliding contact surface being formed in an uneven shape.

4. 4. The vehicle seat frame according to claim 1, wherein the other end of the torsion bar is inserted into a through hole formed in the back frame, and the torsion bar is twisted while being supported by an edge portion of the through hole.

5. The vehicle seat frame according to any one of claims 1 to 4, further comprising a spiral spring, one end of which is fastened to the cushion frame and the other end of which is fastened to the back frame, and which is wound up by reclining the back frame.

6. A seat cushion on which a vehicle occupant sits; a seat back that supports the back of the occupant; The vehicle seat frame according to any one of claims 1 to 5, including a cushion frame that forms a skeleton of the seat cushion and a back frame that forms a skeleton of the seat back; A vehicle seat comprising:

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