Headrest support structure and vehicle seat

Abstract

To obtain a headrest support structure which enables easy injection of grease into a headrest bush.SOLUTION: A headrest support structure has a cylindrical part 32B into which a headrest stay is inserted. A grease injection hole 36 which is open in a radial direction of the cylindrical part 32B includes: a headrest bush 32 formed at the cylindrical part 32B; and silicone grease G which is injected from the grease injection hole 36 into the cylindrical part 32B and disposed between an inner peripheral surface of the cylindrical part 32B and the headrest stay.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a vehicle seat, and more particularly to a headrest support structure. [Background technology]

[0002] The following Patent Document 1 discloses that the bearing of the headrest bush may contain lubricating oil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-536863 A Summary of the Invention [Problem to be solved by the invention]

[0004] The headrest stays inserted into the headrest bushings are sometimes coated with silicone grease as a lubricant. However, because such silicone grease has a high viscosity, it adheres to the area near the top end opening of the headrest bushing and does not penetrate sufficiently into the inside of the headrest bushing. As a result, problems occur such as the operation force required to adjust the headrest up and down becomes heavy and silicone grease adheres to the surface of the headrest.

[0005] SUMMARY OF THE PRESENT INVETION The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a headrest support structure and a vehicle seat that allow easy injection of grease into a headrest bush. [Means for solving the problem]

[0006] The headrest support structure of the first embodiment comprises a headrest bushing having a cylindrical portion into which a headrest stay is inserted, the cylindrical portion having a grease injection hole that opens radially therethrough, and grease that is injected into the cylindrical portion through the grease injection hole and is interposed between the inner surface of the cylindrical portion and the headrest stay.

[0007] In the headrest support structure of the first aspect, the headrest bush has a grease injection hole formed in a cylindrical portion into which the headrest stay is inserted, the grease being injected into the cylindrical portion from the grease injection hole and being open in the radial direction of the cylindrical portion. Grease is then present between the inner peripheral surface of the cylindrical portion and the headrest stay. In this manner, the grease injection hole opening in the radial direction is formed in the cylindrical portion of the headrest bush, making it easy to inject grease into the cylindrical portion of the headrest bush.

[0008] The headrest support structure of the second aspect is the same as that of the first aspect, and further includes a cylindrical cover that is made of an elastic material and attached to the outside of the cylindrical portion to cover the grease injection hole.

[0009] In the headrest support structure of the second aspect, a cylindrical cover made of a stretchable material is attached to the outside of the cylindrical portion of the headrest bush, and the grease injection hole is covered by the cylindrical cover, which makes it possible to prevent grease from leaking or evaporating from the grease injection hole.

[0010] A headrest support structure of a third aspect is the headrest support structure of the second aspect, wherein the cylindrical cover has a through hole, and is rotatable with respect to the cylindrical portion between an open position where the through hole faces the grease injection hole to open the grease injection hole, and a closed position where the grease injection hole is closed.

[0011] In the headrest support structure of the third aspect, by rotating the cylindrical cover to an open position where the through hole of the cylindrical cover faces the grease injection hole, the grease injection hole is opened, and grease can be injected into the cylindrical portion of the headrest bush. When the cylindrical cover is rotated to a closed position, the grease injection hole is closed by the cylindrical cover. In this way, since the cylindrical cover is rotatable, the grease injection hole can be easily opened and closed.

[0012] The headrest support structure of the fourth aspect, in the first aspect, is provided with a C-shaped cover that is formed in an approximately cylindrical shape with a C-shaped cross section, is attached to the outside of the cylindrical portion, and is rotatable relative to the cylindrical portion between an open position that opens the grease injection hole and a closed position that closes the grease injection hole.

[0013] In the headrest support structure of the fourth aspect, the C-shaped cover, which is formed in a generally cylindrical shape with a C-shaped cross section and is attached to the outside of the cylindrical portion, is rotated to an open position to open the grease injection hole, making it possible to inject grease into the cylindrical portion of the headrest bush. When the C-shaped cover is rotated to a closed position, the grease injection hole is closed by the C-shaped cover. This makes it possible to prevent grease from leaking or volatilizing from the grease injection hole. In this way, since the C-shaped cover is rotatable, the grease injection hole can be easily opened and closed.

[0014] A vehicle seat of a fifth aspect includes a seat cushion on which an occupant sits, a seat back that supports the back of the occupant, a headrest that supports the head of the occupant, and a headrest support structure of any one of the first to fourth aspects attached to an upper end of the seat back, the headrest stay of the headrest being inserted into the tubular portion of the headrest bush.

[0015] In the vehicle seat of the fifth aspect, the back of an occupant seated on a seat cushion is supported by the seat back, and the head of the occupant is supported by a headrest. A headrest stay of the headrest is inserted into a cylindrical portion of a headrest bush attached to an upper end of the seat back. This headrest bush constitutes the headrest support structure of any one of the first to fourth aspects, and therefore the above-mentioned effects can be obtained. Effect of the Invention

[0016] As described above, according to the present invention, injection of grease into the headrest bushing becomes easy. [Brief description of the drawings]

[0017] [Figure 1] 1 is a perspective view showing a vehicle seat according to a first embodiment. [Diagram 2] 2 is a perspective view showing a headrest bush provided in the headrest support structure in accordance with the first embodiment. FIG. [Diagram 3] FIG. 2 is a perspective view showing a cylindrical cover included in the headrest support structure according to the first embodiment. [Figure 4] 11 is a perspective view showing a state in which a cylindrical cover is attached to a headrest bush. FIG. [Diagram 5] FIG. 11 is a perspective view showing a headrest and a headrest bush according to a comparative example. [Figure 6] 11 is a cross-sectional view showing a state in which silicone grease applied to a headrest stay of a headrest according to a comparative example is attached near an upper end opening of a headrest bush. FIG. [Figure 7] 11 is a cross-sectional view showing a state in which silicone grease is injected into a headrest bush from an upper end opening of the headrest bush. FIG. [Figure 8] 10 is a cross-sectional view showing a state in which silicone grease is injected into a cylindrical portion of a headrest bush through a grease injection hole formed in the cylindrical portion. FIG. [Figure 9] FIG. 13 is a perspective view showing a modified example of the cylindrical cover. [Figure 10] FIG. 11 is a perspective view showing a cylindrical cover included in the headrest support structure according to the second embodiment. [Figure 11] 11 is a perspective view showing a state in which a cylindrical cover attached to a headrest bush is located in an open position. FIG. [Figure 12] 11 is a perspective view showing a state in which a cylindrical cover attached to a headrest bush is located at a closed position. FIG. [Figure 13] FIG. 11 is a perspective view showing a C-shaped cover included in the headrest support structure according to the third embodiment. [Figure 14] 11 is a perspective view showing a state in which a C-shaped cover attached to a headrest bush is located in an open position. FIG. [Figure 15] 11 is a perspective view showing a state in which a C-shaped cover attached to a headrest bush is located at a closed position. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] <First embodiment> Hereinafter, a vehicle seat 10 according to a first embodiment of the present invention will be described with reference to Figs. 1 to 9. In each drawing, some reference symbols may be omitted in order to make the drawings easier to see. Also, the arrows FR, LH, and UP shown in Fig. 1 indicate the front, left, and top of the vehicle seat 10, respectively. 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.

[0019] As shown in FIG. 1, a vehicle seat 10 according to a first embodiment of the present invention includes a seat cushion 12 on which an occupant sits, a seat back 14 that supports the occupant's back, and a headrest 16 that supports the occupant's head.

[0020] The headrest 16 has a headrest stay 18, a headrest pad 20 supported by the headrest stay 18, and a headrest skin 22 covering the headrest pad 20. The headrest stay 18 is, for example, a metal pipe that is bent and has a generally inverted U-shape when viewed from the front-rear direction. The headrest pad 20 is, for example, made of a foam such as urethane foam that is foam-molded integrally with the headrest stay 18, and the upper part of the headrest stay 18 is embedded in the headrest pad 20. The headrest skin 22 is formed into a bag shape by sewing a plurality of skin pieces made of, for example, a cloth material, leather, synthetic leather, or the like, and is placed over the headrest pad 20.

[0021] The headrest stay 18 of the headrest 16 is supported on the seat back 14 by a headrest support structure 30 according to a first embodiment of the present invention. This headrest support structure 30 is attached to the upper end of the seat back 14, and has two headrest bushes 32 on the left and right into which the two left and right leg portions 18A of the headrest stay 18 are inserted, and silicone grease G (see FIG. 8) injected into each headrest bush 32.

[0022] 2, each headrest bush 32 is manufactured by, for example, injection molding of resin, and is formed into a cylindrical shape as a whole. An insertion hole 34 is formed in each headrest bush 32 from the upper end to the lower end, into which the leg portion 18A of the headrest stay 18 is inserted. A disk-shaped head portion 32A is provided at the upper end of each headrest bush 32, and a substantially cylindrical tubular portion 32B is provided below the head portion 32A.

[0023] The cylindrical portions 32B of the left and right headrest bushings 32 are inserted into two cylindrical brackets, one on each side, provided at the upper end of a frame (not shown) of the seat back 14, and are supported by the frame of the seat back 14. The head portions 32A of the left and right headrest bushings 32 are positioned and exposed above the seat back 14.

[0024] The left and right legs 18A of the headrest stay 18 are inserted from above into the insertion holes 34 of the left and right headrest bushes 32. A locking mechanism (not shown) is provided in the head 32A of one of the headrest bushes 32, which restricts the vertical movement of the leg 18A relative to the one of the headrest bushes 32. A button (not shown) for unlocking the locking mechanism is provided in the head 32A of one of the headrest bushes 32, and pressing this button allows the headrest stay 18, i.e., the headrest 16, to move vertically relative to the left and right headrest bushes 32.

[0025] A grease injection hole 36 that opens in the radial direction of the cylindrical portion 32B is formed in the vertical center (axial center) of the cylindrical portion 32B of each headrest bush 32, and the inside (i.e., the insertion hole 34) and the outside of the cylindrical portion 32B communicate with each other via the grease injection hole 36. The grease injection hole 36 is formed in a circular shape, for example. Silicon grease G (see FIG. 8) injected into the cylindrical portion 32B from the grease injection hole 36 is interposed between the inner peripheral surface of the cylindrical portion 32B and the leg portion 18A of the headrest stay 18. The grease injection hole 36 is closed by a cylindrical cover 40 (see FIG. 3).

[0026] The cylindrical cover 40 is formed in a cylindrical shape from a material having elasticity, and is attached to the outside of the cylindrical portion 32B. For example, a sponge-like material such as urethane foam is used as the material having elasticity. A plurality of protrusions 38 protruding radially outward from the cylindrical portion 32B are formed on the cylindrical portion 32B on both sides of the cylindrical cover 40 in the vertical direction. These protrusions 38 limit the vertical movement of the cylindrical cover 40 relative to the cylindrical portion 32B. When the cylindrical cover 40 is attached to the cylindrical portion 32B, for example, the cylindrical portion 32B is inserted from the lower end side into the inside of the expanded cylindrical cover 40.

[0027] In the vehicle seat 10 having the above-mentioned configuration, the back of the occupant seated on the seat cushion 12 is supported by the seat back 14, and the head of the occupant is supported by the headrest 16. The upper end of the seat back 14 is provided with left and right headrest bushes 32 into which the left and right leg portions 18A of the headrest stay 18 of the headrest 16 are inserted. Each headrest bush 32 has a cylindrical portion 32B into which the leg portion 18A is inserted, and a grease injection hole 36 opening in the radial direction of the cylindrical portion 32B is formed in the vertical center of the cylindrical portion 32B. Silicon grease G injected into the cylindrical portion 32B from the grease injection hole 36 is interposed between the inner peripheral surface of the cylindrical portion 32B and the leg portion 18A. In this way, since the grease injection hole 36 opening in the radial direction is formed in the cylindrical portion 32B of the headrest bush 32, it is easy to inject the silicone grease G into the cylindrical portion 32B.

[0028] The above-mentioned effects will be further explained using comparative examples shown in Figs. 5 to 7. As shown in Fig. 5, conventionally, when inserting the headrest stay 18 into the headrest bush 32, silicone grease G may be applied to the left and right legs 18A. In such a case, as shown in Fig. 6, the silicone grease G, which has high viscosity, adheres to the vicinity of the upper end opening of the insertion hole 34 of the headrest bush 32, and the silicone grease G does not sufficiently penetrate inside the headrest bush 32. As a result, problems such as an increase in the operating force required to adjust the vertical position of the headrest 16 and silicone grease G adhering to the headrest skin 22 occur. In addition, the left and right legs 18A of the headrest stay 18 are gently curved and come into contact with the headrest bush 32 locally, so that it is inefficient to apply silicone grease G to the entirety of each leg 18A.

[0029] Also, as shown in Fig. 7, when silicone grease G is injected into the headrest bushing 32 from the upper end opening of the insertion hole 34 of the headrest bushing 32, it is difficult to inject the silicone grease G to the back of the cylindrical portion 32B because the viscosity of the silicone grease G is high. In this regard, in this embodiment, as shown in Fig. 8, silicone grease G is injected into the cylindrical portion 32B from a grease injection hole 36 formed in the center of the cylindrical portion 32B in the up-down direction, so that the silicone grease G can be properly distributed inside the cylindrical portion 32B. In Figs. 7 and 8, 42 denotes a grease gun.

[0030] In this embodiment, a cylindrical cover 40 made of a stretchable material and formed into a cylindrical shape is attached to the outside of the cylindrical portion 32B of the headrest bushing 32, and the grease injection hole 36 is covered by the cylindrical cover 40. This makes it possible to prevent the silicone grease G from leaking or volatilizing from the grease injection hole 36.

[0031] In this embodiment, the cylindrical cover 40 is made of a sponge-like material such as urethane foam, but the cylindrical cover 40 may have a two-layer structure as shown in Fig. 9. In the example shown in Fig. 9, an outer peripheral portion 40A of the cylindrical cover 40 is made of rubber, and an inner peripheral portion 40B of the cylindrical cover 40 is made of a sponge-like material.

[0032] Next, another embodiment of the present invention will be described. Note that the same reference numerals as in the first embodiment are given to the configurations and operations that are basically the same as those in the first embodiment, and the description thereof will be omitted.

[0033] <Second embodiment> Figure 10 shows an oblique view of a tubular cover 50 provided in a headrest support structure of the second embodiment of the present invention, Figure 11 shows an oblique view of the tubular cover 50 attached to the headrest bush 32 in an open position, and Figure 12 shows an oblique view of the tubular cover 50 attached to the headrest bush 32 in a closed position.

[0034] The cylindrical cover 50 has the same configuration as the cylindrical cover 40 according to the first embodiment, except that it has a through hole 52. The through hole 52 is formed in a circular shape, for example. The cylindrical cover 50 is rotatable with respect to the cylindrical portion 32B between an open position (position shown in FIG. 11) where the through hole 52 faces the grease injection hole 36 to open the grease injection hole 36, and a closed position (position shown in FIG. 12) where the grease injection hole 36 is closed.

[0035] In this embodiment, by rotating the cylindrical cover 50 to an open position where the through hole 52 of the cylindrical cover 50 faces the grease injection hole 36, the grease injection hole 36 is opened, and it becomes possible to inject silicone grease G into the cylindrical portion 32B of the headrest bushing 32. When the cylindrical cover 50 is rotated to a closed position as shown by the arrow R in Fig. 12, the grease injection hole 36 is closed by the cylindrical cover 50, so that it is possible to prevent the silicone grease G from leaking or volatilizing from the grease injection hole 36. In this way, because the cylindrical cover 50 is rotatable, the grease injection hole 36 can be easily opened and closed.

[0036] <Third embodiment> Figure 13 shows an oblique view of a C-shaped cover 60 provided in a headrest support structure of the third embodiment of the present invention, Figure 14 shows an oblique view of the C-shaped cover 60 attached to the headrest bush 32 in an open position, and Figure 15 shows an oblique view of the C-shaped cover 60 attached to the headrest bush 32 in a closed position.

[0037] The C-shaped cover 60 is formed, for example, from resin into a generally cylindrical shape with a C-shaped cross section, and is rotatably attached to the outside of the cylindrical portion 32B. A slit 62 is formed in the C-shaped cover 60. The C-shaped cover 60 is rotatable with respect to the cylindrical portion 32B between an open position (position shown in FIG. 14) where the slit 62 faces the grease injection hole 36 to open the grease injection hole 36, and a closed position (position shown in FIG. 15) where the grease injection hole 36 is closed.

[0038] In this embodiment, by rotating the C-shaped cover 60 to an open position where the slit 62 of the C-shaped cover 60 faces the grease injection hole 36, the grease injection hole 36 is opened, and it becomes possible to inject silicone grease into the cylindrical portion 32B of the headrest bushing 32. When the C-shaped cover 60 is rotated to a closed position as shown by the arrow R in Fig. 15, the grease injection hole 36 is closed by the C-shaped cover 60, so that it is possible to prevent the silicone grease G from leaking or volatilizing from the grease injection hole 36. In this way, because the C-shaped cover 60 is rotatable, the grease injection hole 36 can be easily opened and closed.

[0039] Although the present invention has been described above with reference to several embodiments, the present invention can be modified and embodied without departing from the spirit and scope of the present invention. Furthermore, the scope of the present invention is not limited to the above-described embodiments. [Explanation of symbols]

[0040] 10 Vehicle seats 12 Seat cushion 14 Seat back 16 Headrest 18 Headrest stay 18A Legs 30 Headrest support structure 32 Headrest bush 32B Cylindrical part 36 Grease injection hole 40 Cylindrical cover 50 Cylindrical cover 52 Through hole 60 C-shaped cover

Claims

1. a headrest bushing having a cylindrical portion into which a headrest stay is inserted, the cylindrical portion having a grease injection hole formed therein and opening in a radial direction of the cylindrical portion; Grease injected into the cylindrical portion through the grease injection hole and interposed between an inner circumferential surface of the cylindrical portion and the headrest stay; A headrest support structure comprising:

2. 2. The headrest support structure according to claim 1, further comprising a cylindrical cover made of a stretchable material and attached to the outside of said cylindrical portion, said cylindrical cover covering said grease injection hole.

3. The headrest support structure described in claim 2, wherein the cylindrical cover has a through hole and is rotatable relative to the cylindrical portion between an open position in which the through hole faces the grease injection hole to open the grease injection hole, and a closed position in which the grease injection hole is closed.

4. 2. The headrest support structure as described in claim 1, further comprising a C-shaped cover that is formed in an approximately cylindrical shape with a C-shaped cross section, is attached to the outside of the cylindrical portion, and is rotatable relative to the cylindrical portion between an open position that opens the grease injection hole and a closed position that closes the grease injection hole.

5. A seat cushion on which an occupant sits; A seat back that supports the back of the occupant; A headrest for supporting the head of the occupant; 3. The headrest support structure according to claim 1 or 2, wherein the headrest support structure is attached to an upper end portion of the seat back, and a headrest stay of the headrest is inserted into the cylindrical portion of the headrest bush; A vehicle seat comprising:

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