Seat sliding device

Abstract

The invention relates to a seat sliding device. The seat sliding device comprises a lower rail, an upper rail, a screw shaft, a nut in threaded connection to the screw shaft, an elastic component capable of vertically and movably holding the nut, and a support for fixing the elastic component to the bottom wall of the lower rail. The nut is inserted into an elastic member having a box shape. The bracket supports the elastic member and includes a first bracket and a second bracket facing an upper surface and a lower surface of the nut, respectively. The nut has a cross-shaped shape when viewed in a cross-section perpendicular to the axis of the screw shaft, and includes an upper projection extending through the first rectangular hole of the first bracket and a lower projection extending through the second rectangular hole of the second bracket.

Description

Technical Field

[0001] The present disclosure relates to a seat sliding device for a seat of a vehicle. Specifically, the present disclosure relates to a seat sliding device configured to electrically move a seat in the front-rear direction of the vehicle. Background Art

[0002] Japanese Patent Application Publication JP2010-047172A corresponding to US2010 / 0044542A1 discloses an electric seat sliding device including a nut covered by an elastic member and including a bracket surrounding and holding the nut. This allows adjustment of the axis of the screw hole of the nut and the axis of the screw shaft. The nut is movably or slidably supported in the vertical direction and the left-right direction and is moved to align the axis of the screw hole of the nut with the axis of the screw shaft. This can suppress noise and vibration generated by the rotation of the screw shaft.

[0003] In the above electric seat sliding device, when the upper rail and the lower rail mechanically collide and thereby adjust the stroke range of the upper rail relative to the lower rail, it is very likely that the screw shaft and the elastic member will bite because even after the upper rail stops, the screw shaft will continue to rotate and compress the elastic member. This biting increases the operating force during the reverse operation of the screw shaft, causing the screw shaft to reverse and generating noise and vibration.

[0004] As a countermeasure to solve this problem, Japanese Patent Application Publication JP2022-030546A and Japanese Patent Application Publication JP2011-031667A respectively disclose an electric seat sliding device including a nut with a protrusion. The protrusion of the nut is formed on the facing surface of the nut facing the bracket surrounding the nut, enabling the nut to directly contact the bracket. This can suppress the elastic member from being compressed beyond expectation. Summary of the Invention

[0005] The electric seat sliding devices disclosed in the above Japanese Patent Application Publications JP2022-030546A and JP2011-031667A include protrusions on the facing surface of the nut. This makes the shape of the nut complex, reduces the machinability of the nut, and increases the manufacturing cost of the nut. In addition, the protrusions on the facing surface of the nut also make the shape of the elastic member complex because the shape of the elastic member must avoid the protrusions. This increases the manufacturing cost of the elastic member.

[0006] In view of the above conventional situation, it is desirable to simplify the shapes of the nut and the elastic member and improve their machinability without reducing the function of adjusting the axis of the screw hole of the nut and the axis of the screw shaft.

[0007] According to one aspect of the present disclosure, a seat sliding device for a vehicle includes: a lower rail extending in the longitudinal direction of the vehicle; an upper rail configured to be relatively movable with respect to the lower rail in the longitudinal direction of the lower rail; a screw shaft mounted to a first one of the lower rail and the upper rail so as to be rotatable and extending in the longitudinal direction of the lower rail; a nut mounted to a second one of the lower rail and the upper rail, including a screw hole extending in the front-rear direction through the nut and threadedly connected to the screw shaft; an elastic member having a rectangular box shape and including: a ceiling wall covering the upper surface of the nut and including a ceiling wall rectangular hole; a rectangular tubular wall extending from an edge of the ceiling wall and covering the front, rear, right, and left surfaces of the nut; and a through hole overlapping the screw hole of the nut in the front-rear direction; and a bracket supporting the elastic member so as to cover the front, rear, upper, and lower surfaces of the nut from the outside of the elastic member. The bracket includes a first bracket and a second bracket. The first bracket includes: a first upper wall facing the upper surface of the nut and including a first rectangular hole; a pair of first walls extending downward from both ends of the first upper wall in the front-rear direction and respectively facing the front and rear surfaces of the nut; and a pair of first mounting walls extending in the front-rear direction from lower ends of the pair of first walls so as to extend away from each other. The second bracket includes: a second upper wall facing the lower surface of the nut and including a second rectangular hole; a pair of second walls extending downward from both ends of the second upper wall in the front-rear direction and respectively facing the pair of first walls of the first bracket; and a pair of second mounting walls extending in the front-rear direction from lower ends of the pair of second walls so as to extend away from each other and mounted to the bottom wall of the lower rail together with the pair of first mounting walls of the first bracket. The nut has a cross-shaped shape when viewed in a cross-section in a direction perpendicular to the axis of the screw shaft, and includes: an upper protrusion extending through the ceiling wall rectangular hole of the ceiling wall of the elastic member and through the first rectangular hole of the first upper wall of the first bracket; and a lower protrusion protruding downward through an opening of the elastic member and extending through the second rectangular hole of the second upper wall of the second bracket.

[0008] The above aspect of the present disclosure helps to simplify the shapes of the nut and the elastic member and improve their workability, while not reducing the function of adjusting the axes of the screw hole of the nut and the screw shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is an exploded perspective view of a seat sliding device according to an embodiment of the present disclosure.

[0010] Figure 2 is a perspective view of the seat sliding device according to the embodiment.

[0011] Figure 3 is a sectional view of the seat sliding device taken along Figure 2 the line A-A shown.

[0012] Figure 4 It is a perspective view of a nut in a seat sliding device according to this embodiment.

[0013] Figure 5 It is a perspective view of an elastic member used in a seat sliding device according to this embodiment.

[0014] Figure 6 It is a side view showing how to install the nut.

[0015] Figure 7 is with Figure 6 A longitudinal sectional view along the vehicle front-rear direction corresponding thereto, showing how to install the nut.

[0016] Figure 8 is along Figure 7 A sectional view taken along line B-B shown, showing how to install the nut. Detailed implementation

[0017] An embodiment will be described below with reference to the drawings, taking a seat sliding device applied to a vehicle seat as an example.

[0018] Figure 1 It is an exploded perspective view of a seat sliding device according to an embodiment of the present application. Figure 2 It is a perspective view of the seat sliding device. Figure 3 is the seat sliding device along Figure 2 A sectional view taken along line A-A shown. Hereinafter, the "vehicle front-rear direction" refers to the longitudinal direction of the lower rail 1. Refer to Figure 1 and Figure 2 , the front side in the vehicle front-rear direction is the side where the electric motor 5 is provided, and the rear side in the vehicle front-rear direction is the side where the end cap 15 is provided. In addition, the "vertical direction" refers to the vertical direction when the seat sliding device is fixed to the floor of the vehicle body: in other words, it refers to the direction perpendicular to the floor of the vehicle body, that is, the height direction of the vehicle body. The "left-right direction" refers to the left-right direction when the seat sliding device is fixed to the floor of the vehicle body: in other words, it refers to the direction perpendicular to both the vehicle front-rear direction and the vertical direction.

[0019] The seat sliding device in a vehicle includes a lower rail 1, an upper rail 2, a screw shaft 3, a gearbox 4, an electric motor 5, a nut 6, an elastic member 7, and a bracket 8. The lower rail 1 extends in the longitudinal direction of the vehicle. The upper rail 2 is capable of relatively moving with respect to the lower rail 1 in the longitudinal direction of the lower rail 1 and forms a rail assembly with the lower rail 1. The screw shaft 3 is mounted on the upper rail 2 so as to be rotatable and extends in the longitudinal direction of the lower rail 1. The gearbox 4 includes a gear mechanism configured to rotate the screw shaft 3. The electric motor 5 applies a rotational force to the screw shaft 3 via the gear mechanism of the gearbox 4. The nut 6 is mounted on the lower rail 1 and is threadedly connected to the screw shaft 3. The elastic member 7 surrounds and holds the nut 6. The bracket 8 fixes the nut 6 to the lower rail 1 via the elastic member 7 such that the nut 6 can move in the vertical direction.

[0020] The lower rail 1 is formed by bending the left and right ends of an elongated metal sheet through stamping. As Figure 3 shown, the lower rail 1 includes a bottom wall 1a, a pair of first inclined walls 1b and 1c, a pair of outer side walls 1d and 1e, a pair of upper walls 1f and 1g, and a pair of inner side walls 1h and 1i. The bottom wall 1a is fixed to the floor plate of the vehicle body via a fixing member (not shown). The first inclined walls 1b and 1c extend outward from the left and right ends of the bottom wall 1a and are bent upwardly and obliquely. The outer side walls 1d and 1e extend upward from the upper ends of the first inclined walls 1b and 1c and are bent upwardly. The upper walls 1f and 1g extend inward from the upper ends of the outer side walls 1d and 1e and are bent inwardly. The inner side walls 1h and 1i extend downward from the inner ends of the upper walls 1f and 1g and are substantially parallel to the outer side walls 1d and 1e.

[0021] The upper rail 2 is formed by bending the left and right ends of an elongated metal sheet through stamping. As Figure 3 shown, the upper rail 2 includes a top wall 2a, a pair of side walls 2b and 2c, a pair of lower ball holding walls 2d and 2e, a pair of second inclined walls 2f and 2g, and a pair of upper ball holding walls 2h and 2i. The top wall 2a is mounted on the bottom surface of the seat via a fixing member (not shown). The side walls 2b and 2c extend downward from the left and right ends of the top wall 2a and are substantially perpendicular to the top wall 2a. The lower ball holding walls 2d and 2e extend outward from the lower ends of the side walls 2b and 2c and are bent in an arc shape. The second inclined walls 2f and 2g extend upward from the upper ends of the lower ball holding walls 2d and 2e and are inclined respectively toward the outer side walls 1d and 1e. The upper ball holding walls 2h and 2i extend inward from the upper ends of the second inclined walls 2f and 2g and are bent in an arc shape.

[0022] As Figure 3As shown, the lower ball retaining walls 2d and 2e respectively include upwardly convex lower arcuate surfaces s1 and s2. The lower guide balls 9 and 10 are inserted between the lower arcuate surfaces s1 and s2 and the arcuate surfaces s5 and s6. The arcuate surfaces s5 and s6 are formed between the bottom wall 1a of the lower track 1 and the first inclined walls 1b and 1c, and are downwardly convex. The lower guide balls 9 and 10 are capable of rolling. This can reduce the friction between the lower track 1 and the upper track 2, and allow the upper track 2 to move smoothly relative to the lower track 1.

[0023] As Figure 3 shown, the upper ball retaining walls 2h and 2i respectively include downwardly convex upper arcuate surfaces s3 and s4. The upper guide balls 11 and 12 are inserted between the upper arcuate surfaces s3 and s4 and the arcuate surfaces s7 and s8. The arcuate surfaces s7 and s8 are formed between the outer side walls 1d and 1e and the upper walls 1f and 1g. The upper guide balls 11 and 12 are capable of rolling, and their diameters are smaller than the diameters of the lower guide balls 9 and 10. The rolling of the upper guide balls 11 and 12 reduces the friction between the lower track 1 and the upper track 2, and allows the upper track 2 to move smoothly relative to the lower track 1.

[0024] The lower guide balls 9 and 10 and the upper guide balls 11 and 12 are supported by ball holders 13 and 14 that extend through the gaps between the outer side walls 1d and 1e and the second inclined walls 2f and 2g.

[0025] As Figure 1 and Figure 2 shown, the lower track 1 includes two pairs of tongue-shaped stoppers 1j near the front end and the rear end of the lower track 1. The tongue-shaped stoppers 1j are formed by cutting a part of the upper ends of the outer side walls 1d and 1e and making the part protrude inward relative to the outer side walls 1d and 1e. The tongue-shaped stoppers 1j engage with the ball holders 13 and 14, thereby serving to prevent the lower guide balls 9 and 10 and the upper guide balls 11 and 12 from escaping from the inside of the lower track 1.

[0026] As Figures 1 to 3 shown, the bottom wall 1a of the lower track 1 includes two pairs of tongues 1k that are positioned inside relative to the two pairs of tongue-shaped stoppers 1j in the vehicle front-rear direction. The tongues 1k are formed by cutting a part of the bottom wall 1a and making the part protrude to one side of the outer side walls 1d and 1e. As Figure 3 shown, the left tongue and the right tongue in the tongues 1k respectively contact the left pair of protrusions and the right pair of protrusions 2j of the upper track 2. The protrusions 2j are formed on the side walls 2b and 2c by not bending the lower ends of the side walls 2b and 2c outward. Therefore, the protrusions 2j of the upper track 2 are configured to mechanically collide with the tongues 1k of the lower track 1, thereby adjusting the stroke range of the upper track 2 relative to the lower track 1.

[0027] The screw shaft 3 is made of metal, is cylindrical, is slender, has a length substantially equal to that of the upper rail 2, and is disposed between a pair of side walls 2b and 2c of the upper rail 2. As Figure 1 shown, the screw shaft 3 includes a body 3a, a first small-diameter portion 3b, a wheel fixing portion 3c, and a second small-diameter portion 3e. The first small-diameter portion 3b is integrally formed with the front end of the body 3a, and has a diameter smaller than that of the body 3a. The wheel fixing portion 3c is integrally formed with the front end of the first small-diameter portion 3b, and has a diameter smaller than that of the body 3a and larger than that of the first small-diameter portion 3b. The second small-diameter portion 3e is integrally formed with the rear end of the body 3a, and has a diameter smaller than that of the body 3a.

[0028] The body 3a includes an outer peripheral surface which includes an external thread 3f. The external thread 3f is threadedly connected to an internal thread hole 6a of the nut 6. The threaded connection between the external thread 3f and the internal thread hole 6a causes the screw shaft 3 to move in the vehicle longitudinal direction relative to the nut 6 in response to the rotation of the screw shaft 3.

[0029] The wheel fixing portion 3c includes an outer peripheral surface which includes a serrated structure 3g. The serrated structure 3g cooperates with a worm wheel (not shown) provided in the gear box 4. The worm wheel engages with a worm shaft (not shown) fixed to the motor shaft of the electric motor 5 and is a component of the gear mechanism. Although Figure 1 and Figure 2 the electric seat sliding device is illustrated as being positioned on the left side of the seat, in fact, in addition to the electric motor 5, another electric seat sliding device is also positioned on the right side of the seat. The electric motor 5 is connected to the gear box of the right-side electric seat sliding device via a connector (not shown). Accordingly, the electric motor 5 rotates the screw shaft 3 of the left-side electric seat sliding device and the screw shaft 3 of the right-side electric seat sliding device to synchronize them.

[0030] The second small-diameter portion 3e is supported within a tube 15a of the end cap 15 so as to be rotatable, and has a diameter smaller than that of the body 3a of the screw shaft 3 to avoid interference with the internal thread hole 6a of the nut 6. The end cap 15 includes a pair of engaging claws 15b which are formed integrally with the outer periphery of the tube 15a. The pair of engaging claws 15b engage with a pair of engaging grooves 2k formed on the side walls 2b and 2c of the upper rail 2, thereby fixing the end cap 15 to the side walls 2b and 2c.

[0031] The upper rail 2 includes a pair of mounting portions 2m at the front ends of the side walls 2b and 2c. The mounting portions 2m are the portions to which the gear box 4 is mounted. Each mounting portion 2m includes a through hole 2n which extends through the corresponding side wall 2b and 2c in the thickness direction of the side wall. Via the two through holes 2n, the gear box 4 is mounted to the mounting portion 2m using fixing members (such as the plug pin 23 in the embodiment of the present application).

[0032] The upper rail 2 is provided with reinforcing plates 16 and 17 which are mounted to the upper rail 2 near the front end and the rear end thereof. The reinforcing plates 16 and 17 are substantially rectangular plates and are similar in shape to each other. The reinforcing plates 16 and 17 are provided perpendicular to the top wall 2a of the upper rail 2.

[0033] The following description will be made taking the reinforcing plate 16 as a representative. The reinforcing plate 16 includes a pair of recessed portions 16a, a pair of expanded portions 16b, a pair of depressed portions 16c, and a protrusion 16d. At the left and right ends of the recessed portion 16a, the recessed portion 16a is positioned near the upper end of the reinforcing plate 16 and is recessed inward. At the left and right ends of the recessed portion 16a, the expanded portions 16b are positioned lower than the recessed portion 16a and expand outward. The depressed portions 16c are positioned near the center of the top of the reinforcing plate 16 and are recessed inward. The protrusion 16d is positioned between the pair of depressed portions 16c and protrudes upward from the top of the reinforcing plate 16. As Figure 3 shown, the recessed portion 16a engages with the cut and protruded portion 2o which is formed in the side walls 2b and 2c of the upper rail 2 by cutting a part of the side walls 2b and 2c and protruding the part inward. This can prevent the reinforcing plate 16 from falling off the upper rail 2. As Figure 3 shown, the expanded portions 16b are inserted into a pair of slits 2p formed in the side walls 2b and 2c, and the protrusion 16d is inserted into a hole 2q formed in the top wall 2a of the upper rail 2. As Figure 1 shown, the reinforcing plate 16 further includes an annular protrusion 16e which protrudes from the front surface of the reinforcing plate 16 toward a stopper 18 described below. The annular protrusion 16e enhances the rigidity of the reinforcing plate 16, thereby suppressing deformation of the reinforcing plate 16 due to contact with the stopper 18 in the case where the upper rail 2 moves forward due to a vehicle collision.

[0034] As Figure 3 shown, the reinforcing plate 16 includes a through hole 16f which extends in the vehicle front-rear direction through the reinforcing plate 16. The through hole 16f receives a screw shaft 3 which is inserted therein. The inner diameter of the through hole 16f is larger than the outer diameter of the screw shaft 3. This allows the screw shaft 3 inserted in the through hole 16f to rotate.

[0035] The screw shaft 3 is provided with a stopper 18 and a stopper 19. The stopper 18 is positioned on the body 3a of the screw shaft 3 in front of the reinforcing plate 16. The stopper 19 is positioned on the body 3a of the screw shaft 3 behind the reinforcing plate 17. Each of the stoppers 18 and 19 is a lock nut including a partially pre-crushed thread, and is thread-connected to a predetermined position of the body 3a and fixed at that predetermined position. The lock nut including a partially pre-crushed thread can be replaced with an ordinary nut including an uncrushed thread. In this case, the ordinary nut serving as the stopper is thread-connected to a predetermined position of the body 3a, and is pressed and packed from the outside to the inside of the stopper, thereby being fixed to the body 3a.

[0036] In the case where the upper rail 2 is subjected to a collision load directed forward in the vehicle longitudinal direction due to a vehicle collision or the like, the reinforcing plate 16 moves forward and collides with the stopper 18 positioned in front of the reinforcing plate 16. This suppresses the gearbox 4 mounted on the upper rail 2 from directly receiving the collision load, thereby suppressing the gearbox 4 from receiving a collision load that separates the gearbox 4 from the screw shaft 3. In this case, the screw shaft 3 is subjected to a traction force.

[0037] In the case where the upper rail 2 is subjected to a collision load directed backward in the vehicle longitudinal direction due to a vehicle collision or the like, the reinforcing plate 17 moves backward and collides with the stopper 19 positioned behind the reinforcing plate 17. This suppresses the gearbox 4 mounted on the upper rail 2 from directly receiving the collision load, thereby suppressing the gearbox 4 from pressing the screw shaft 3 due to the collision load. In this case, the screw shaft 3 is also subjected to a traction force.

[0038] Figure 4 is a perspective view of the nut 6. In Figure 4 , the vehicle longitudinal direction corresponds to the right diagonal direction indicated by the "front" and "rear" arrows in the figure. The vertical direction corresponds to the up and down direction in the figure. The left and right direction corresponds to the direction indicated by the "right" and "left" arrows in the figure.

[0039] The manufacturing method of the nut 6 is: deforming the outer periphery of a metal rectangular column block by stamping; and forming an internal thread hole 6a extending in the vehicle longitudinal direction at the center of the nut 6 in the vertical direction and the left and right direction. The shape of the block before stamping is not limited to a rectangular column, and may also be other shapes, such as a circular column. As Figure 1 and Figure 4As shown, when viewed from the front-rear direction of the vehicle, the shape of the nut 6 is a cross shape that is symmetric in the vertical direction and symmetric in the left-right direction. In the embodiment of the present application, the cross shape of the nut 6 is formed by the intersection of a first part and a second part. Wherein, assuming that the internal thread hole 6a of the nut 6 does not exist and is filled with a metal material, the first part and the second part are respectively the part of the nut 6 that is continuous in the vertical direction and the part of the nut 6 that is continuous in the left-right direction. In addition, the shape of the nut 6 is formed to be symmetric also in the front-rear direction of the vehicle, that is, the cross shape of the nut 6 is continuous in the front-rear direction of the vehicle. This naturally results in the cross shape of the cross section of the nut 6 in the direction perpendicular to the front-rear direction of the vehicle (such as the vertical direction or the left-right direction) (see Figure 8 ).

[0040] As Figure 1 and Figure 4 shown, the nut 6 includes an internal thread hole 6a, an upper protrusion 6b, a lower protrusion 6c, a right protrusion 6d, and a left protrusion 6e. The upper protrusion 6b protrudes upward from one side above the internal thread hole 6a. The lower protrusion 6c protrudes downward from one side below the internal thread hole 6a. The right protrusion 6d protrudes to the right from one side on the right of the internal thread hole 6a (that is, the left side in Figure 4 ). The left protrusion 6e protrudes to the left from one side on the left of the internal thread hole 6a (that is, the right side in Figure 4 ). The shapes of the upper protrusion 6b and the lower protrusion 6c are similar to each other. The shapes of the right protrusion 6d and the left protrusion 6e are similar to each other.

[0041] The upper protrusion 6b includes a left surface 6b1, a right surface 6b2, a front surface 6b3, a rear surface 6b4, and an arc-shaped upper surface 6b5. The left surface 6b1 is exposed to the left and has a rectangular shape, where the long side extends in the front-rear direction of the vehicle. The right surface 6b2 is exposed to the right and has a rectangular shape, where the long side extends in the front-rear direction of the vehicle. The front surface 6b3 is exposed forward and has a substantially rectangular shape. The rear surface 6b4 is exposed backward and has a substantially rectangular shape. The arc-shaped upper surface 6b5 is exposed upward, and when viewed from the front-rear direction of the vehicle, the arc-shaped upper surface has an upwardly convex arc shape.

[0042] The lower protrusion 6c includes a left surface 6c1, a right surface 6c2, a front surface 6c3, a rear surface 6c4, and an arc-shaped lower surface 6c5. The left surface 6c1 is exposed to the left and has a rectangular shape, where the long side extends in the front-rear direction of the vehicle. The right surface 6c2 is exposed to the right and has a rectangular shape, where the long side extends in the front-rear direction of the vehicle. The front surface 6c3 is exposed forward and has a substantially rectangular shape. The rear surface 6c4 is exposed backward and has a substantially rectangular shape. The arc-shaped lower surface 6c5 is exposed downward, and when viewed from the front-rear direction of the vehicle, the arc-shaped lower surface has a downwardly convex arc shape.

[0043] The right protrusion 6d includes an upper surface 6d1, a lower surface 6d2, a front surface 6d3, a rear surface 6d4, and a right surface 6d5. The upper surface 6d1 is exposed upward and has a rectangular shape, with its long side extending in the vehicle front-rear direction. The lower surface 6d2 is exposed downward and has a rectangular shape, with its long side extending in the vehicle front-rear direction. The front surface 6d3 is exposed forward and has a generally rectangular shape, with its long side extending in the vertical direction. The rear surface 6d4 is exposed backward and has a generally rectangular shape, with its long side extending in the vertical direction (see Figure 1 ). The right surface 6d5 is exposed rightward and has a rectangular shape (see Figure 8 ).

[0044] The left protrusion 6e includes an upper surface 6e1, a lower surface 6e2, a front surface 6e3, a rear surface 6e4, and a left surface 6e5. The upper surface 6e1 is exposed upward and has a rectangular shape, with its long side extending in the vehicle front-rear direction. The lower surface 6e2 is exposed downward and has a rectangular shape, with its long side extending in the vehicle front-rear direction. The front surface 6e3 is exposed forward and has a generally rectangular shape, with its long side extending in the vertical direction. The rear surface 6e4 is exposed backward and has a generally rectangular shape, with its long side extending in the vertical direction. The left surface 6e5 is exposed leftward and has a rectangular shape.

[0045] As Figure 4 shown, due to the shape of the die used for stamping, each pair of adjacent surfaces of the nut 6 are smoothly connected via a circular portion R1.

[0046] Figure 5 is a perspective view of the elastic member 7. In Figure 5 , the vehicle front-rear direction corresponds to the thickness direction of the front wall 7d described below. The vertical direction corresponds to the thickness direction of the ceiling wall 7a described below. The left-right direction corresponds to the thickness direction of the left wall 7f described below.

[0047] By molding an elastically deformable material such as rubber, the elastic member 7 has a rectangular box shape, which includes a lower surface with an opening. The elastic member 7 is installed in the bracket 8 and holds the nut 6 while allowing the nut 6 to move in the vertical direction.

[0048] The elastic member 7 includes a ceiling wall 7a and a rectangular tubular wall 7b. The ceiling wall 7a has a rectangular plate shape. The rectangular tubular wall 7b has a rectangular tube shape and extends vertically from the edge of the ceiling wall 7a.

[0049] The ceiling wall 7a includes a ceiling wall rectangular hole 7c that extends vertically through the ceiling wall 7a. The ceiling wall rectangular hole 7c has a rectangular shape, where the long side extends in the vehicle front-rear direction. When looking at the nut 6 from the upper side, the rectangular shape of the ceiling wall rectangular hole 7c is substantially equal in size to the rectangular shape of the arcuate upper surface 6b5 of the upper projection 6b. The ceiling wall rectangular hole 7c receives the upper projection 6b inserted therein. The depth of the ceiling wall rectangular hole 7c in the vertical direction is less than the height of the upper projection 6b in the vertical direction.

[0050] The rectangular tubular wall 7b includes a front wall 7d, a rear wall 7e, a left wall 7f, and a right wall 7g. The front wall 7d extends vertically from the front edge of the ceiling wall 7a. The rear wall 7e extends vertically from the rear edge of the ceiling wall 7a and is opposite to the front wall 7d. The left wall 7f extends vertically from the left edge of the ceiling wall 7a. The right wall 7g extends vertically from the right edge of the ceiling wall 7a and is opposite to the left wall 7f. The front wall 7d and the rear wall 7e are formed into rectangles similar to each other. The left wall 7f and the right wall 7g are formed into rectangles similar to each other. The thickness of the front wall 7d and the rear wall 7e in the vehicle front-rear direction is greater than the thickness of the left wall 7f and the right wall 7g in the left-right direction. In addition, the thickness of the front wall 7d and the rear wall 7e in the vehicle front-rear direction is greater than the thickness of the ceiling wall 7a in the vertical direction.

[0051] The front wall 7d includes a first damper through-hole 7h that has a circular shape and extends through the front wall 7d in the vehicle front-rear direction. When viewed from the vehicle front-rear direction, the first damper through-hole 7h overlaps with the internal thread hole 6a of the nut 6 that extends through the nut 6 in the vehicle front-rear direction. The inner diameter of the first damper through-hole 7h is greater than the outer diameter of the screw shaft 3, and receives the screw shaft 3 inserted in the first damper through-hole 7h.

[0052] The rear wall 7e includes a second damper through-hole 7i that has a circular shape similar to the first damper through-hole 7h and extends through the rear wall 7e in the vehicle front-rear direction. When viewed from the vehicle front-rear direction, the second damper through-hole 7i overlaps with the internal thread hole 6a of the nut 6 that extends through the nut 6 in the vehicle front-rear direction. The inner diameter of the second damper through-hole 7i is greater than the outer diameter of the screw shaft 3, and receives the screw shaft 3 inserted in the second damper through-hole 7i.

[0053] The elastic member 7 has a width W1 in the vehicle front-rear direction, which is set to a value that allows the elastic member 7 to be press-fitted into the gap between a pair of first walls 20b of the first bracket 20 of the bracket 8 described below.

[0054] The width W2 in the vehicle front-rear direction between the front wall 7d and the rear wall 7e is equal to the width of the ceiling wall rectangular hole 7c in the vehicle front-rear direction and corresponds to the width of the nut 6 in the vehicle front-rear direction (e.g., the width from the front surface 6e3 to the rear surface 6e4 of the left projection 6e).

[0055] The width W3 of the rectangular tubular wall 7b in the left-right direction corresponds to the width of the first upper wall 20a of the first bracket 20 of the bracket 8 described below in the left-right direction (see Figure 8 ). The width W4 in the left-right direction between the left wall 7f and the right wall 7g corresponds to the width of the nut 6 in the left-right direction (i.e., the width from the right surface 6d5 of the right projection 6d to the left surface 6e5 of the left projection 6e).

[0056] Reference will be made again below to Figure 1 describe the bracket 8.

[0057] The bracket 8 holds the elastic member 7 (which holds the nut 6) and fixes the elastic member 7 in the vehicle front-rear direction to a position in front of the center of the bottom wall 1a of the lower rail 1. The bracket 8 includes a first bracket 20 and a second bracket 21 provided below the first bracket 20.

[0058] The first bracket 20 is formed by bending a metal plate through stamping and includes a first upper wall 20a, a pair of first walls 20b, and a pair of first mounting walls 20c. The first walls 20b extend downward and bend from both ends of the first upper wall 20a in the vehicle front-rear direction and are perpendicular to the first upper wall 20a. The first mounting walls 20c extend and bend in the vehicle front-rear direction from the lower ends of the first walls 20b so as to be away from each other. Each first wall 20b is connected to the first upper wall 20a via a circular portion R2 formed due to the bending of the metal plate. Similarly, each first mounting wall 20c is connected to the corresponding first wall 20b via a circular portion R3 formed due to the bending of the metal plate.

[0059] The first upper wall 20a includes a first rectangular hole 20d at its center, which extends vertically through the first upper wall 20a. The first rectangular hole 20d has a rectangular shape, where the long side extends in the vehicle front-rear direction, and the first rectangular hole receives the upper projection 6b of the nut 6 inserted in the first rectangular hole 20d. The first rectangular hole 20d includes a front end face 20d1 and a rear end face 20d2, and the rear end face is positioned behind the front end face 20d1 in the vehicle front-rear direction.

[0060] Each of the pair of first walls 20b includes an insertion hole 20e that extends through each first wall 20b in the vehicle front-rear direction. Each insertion hole 20e has a vertically elongated shape, is positioned closer to the circular portion R2 than the other end in the first wall 20b, and has an inner diameter larger than the outer diameter of the screw shaft 3 so as to receive the screw shaft 3 inserted in each insertion hole 20e. As Figure 7 shown, the vertical diameter of the hole of each insertion hole 20e is substantially equal to the circular hole diameter of the first damper through-hole 7h and the second damper through-hole 7i.

[0061] Each of the pair of first mounting walls 20c includes a first mounting hole 20f that extends through the corresponding first mounting wall of the pair of first mounting walls 20c in the vertical direction. When the first bracket 20 and the second bracket 21 are mounted to the lower rail 1, each first mounting hole 20f receives a fastener 22 inserted in each first mounting hole 20f.

[0062] The second bracket 21 is formed by bending a metal plate having a thickness smaller than that of the first bracket 20, and includes a second upper wall 21a, a pair of second walls 21b, and a pair of second mounting walls 21c. The second walls 21b extend downward and bend from both ends of the second upper wall 21a in the vehicle front-rear direction and are perpendicular to the second upper wall 21a. The second mounting walls 21c extend from the lower ends of the second walls 21b and bend in the vehicle front-rear direction so as to be away from each other. Each second wall 21b is connected to the second upper wall 21a via a circular portion R4 formed by bending the metal plate. Similarly, each second mounting wall 21c is connected to the corresponding second wall 21b via a circular portion R5 formed by bending the metal plate.

[0063] The second upper wall 21a includes a second rectangular hole 21d at its center that extends through the second upper wall 21a in the vertical direction. The second rectangular hole 21d has a rectangular shape, where the long side extends in the vehicle front-rear direction. The shape of the second rectangular hole 21d is similar to the shape of the first rectangular hole 20d on the first upper wall 20a of the first bracket 20, and the rectangular shape of the second rectangular hole 21d is equal to the rectangular shape of the first rectangular hole 20d in terms of the length in the vehicle front-rear direction and the width in the left-right direction. In addition, the second rectangular hole 21d is in the same position as the first rectangular hole 20d in the vehicle front-rear direction. The second rectangular hole 21d receives the nut 6 under-projection 6c inserted in the second rectangular hole 21d. The second rectangular hole 21d includes a front end face 21d1 and a rear end face 21d2, and the rear end face is positioned behind the front end face 21d1 in the vehicle front-rear direction.

[0064] Each of the pair of second mounting walls 21c includes a second mounting hole 21f that extends vertically through the corresponding one of the pair of second mounting walls 21c. When the first bracket 20 and the second bracket 21 are mounted to the lower rail 1, each second mounting hole 21f receives a fastener 22 inserted into each second mounting hole 21f.

[0065] Figure 6 is a side view showing how the nut 6 is mounted in the seat slide device according to an embodiment of the present application. Figure 7 is with Figure 6 corresponding longitudinal cross-sectional view in the vehicle front-rear direction, showing how the nut 6 is mounted. Figure 8 is along Figure 7 sectional view taken along the line B-B shown, showing how the nut 6 is mounted. In Figure 8 for simplicity and clarity, the circular portion R1 is omitted.

[0066] The mounting structure of the nut 6 in the lower rail 1 is described below.

[0067] As Figure 6 and Figure 7 shown, the nut 6 is mounted to the bottom wall 1a of the lower rail 1 via the first bracket 20 and the second bracket 21. The elastic member 7 is interposed between the nut 6 and the first bracket 20 and the second bracket 21. The nut 6 is press-fitted (specifically, a light press-fit that can be easily performed by hand) inside the elastic member 7 (specifically, inside the rectangular tubular wall 7b as described above) to eliminate the gaps extending in the vehicle front-rear direction and the gaps extending in the left-right direction. Although the nut 6 is in press contact with the elastic member 7 without gaps extending in the vehicle front-rear direction or in the left-right direction, this press contact is set to allow the nut 6 to move in the vehicle front-rear direction and the left-right direction to a certain extent. As Figure 8 shown, the ceiling wall 7a of the elastic member 7 includes an upper surface 7a1 that is in close contact with the lower surface 20a2 of the first upper wall 20a of the first bracket 20. In addition, as Figure 7 and Figure 8 shown, the front wall 7d, the rear wall 7e, the left wall 7f, and the right wall 7g of the elastic member 7 respectively include lower surfaces 7d1, 7e1, 7f1, and 7g1 that are in close contact with the upper surface 21a1 of the second upper wall 21a of the second bracket 21.

[0068] The ceiling wall 7a of the elastic member 7 covers the upper surface of the nut 6, that is, the upper surface 6d1 of the right protrusion 6d and the upper surface 6e1 of the left protrusion 6e in this embodiment.

[0069] The rectangular tubular wall 7b of the elastic member 7 covers the four surfaces (right, left, front, and rear surfaces) of the nut 6. Specifically, as Figure 8As shown, the left wall 7f and the right wall 7g of the rectangular tubular wall 7b cover the right surface and the left surface of the nut 6, that is, in this embodiment, the left surface 6e5 of the left projection 6e and the right surface 6d5 of the right projection 6d. The front wall 7d and the rear wall 7e of the rectangular tubular wall 7b cover the front surface and the rear surface, that is, in this embodiment, the front surface 6d3 of the right projection 6d, the front surface 6e3 of the left projection 6e, the rear surface 6d4 of the right projection 6d, and the rear surface 6e4 of the left projection 6e.

[0070] As Figure 8 shown, there is a clearance CL in the vertical direction between the upper surface 21a1 of the second upper wall 21a of the second bracket 21 and each lower surface of the nut 6 except the lower projection 6c (that is, in this embodiment, the lower surface 6d2 and the lower surface 6e2 of the right projection 6d). Through the clearance CL, the nut 6 can move in the vertical direction between the first upper wall 20a of the first bracket 20 and the second upper wall 21a of the second bracket 21. In the state where the nut 6 is installed, the upper projection 6b of the nut 6 extends through the ceiling wall rectangular hole 7c of the ceiling wall 7a and the first rectangular hole 20d of the first upper wall 20a. As Figure 7 and Figure 8 shown, even when the nut 6 moves downward and the lower surfaces 6d2 and 6e2 (that is, the lower surfaces of the nut 6 except the lower projection 6c) contact the second upper wall 21a of the second bracket 21, the upper projection 6b will not come out of the first rectangular hole 20d. Similarly, even when the nut 6 moves upward and the upper surfaces 6d1 and 6e2 (that is, the upper surfaces of the nut 6 except the upper projection 6b) contact the ceiling wall 7a of the elastic member 7 to compress the ceiling wall 7a, the lower projection 6c will not come out of the second rectangular hole 21d. These are achieved by setting the clearance and setting the vertical heights of the upper projection 6b and the lower projection 6c.

[0071] As Figure 8 shown, the upper projection 6b and the lower projection 6c do not come out of the first rectangular hole 20d and the second rectangular hole 21d through which they pass respectively, while the right projection 6d and the left projection 6e travel a distance of the clearance CL in the vertical direction between the first upper wall 20a of the first bracket 20 and the second upper wall 21a of the second bracket 21. Therefore, the upper projection 6b and the lower projection 6c are sufficient in vertical height to prevent the upper projection 6b and the lower projection 6c from coming out of the first rectangular hole 20d of the first bracket 20 or the second rectangular hole 21d of the second bracket 21.

[0072] The upper projection 6b extending through the first rectangular hole 20d has a slight clearance between each of the front end surface 20d1 and the rear end surface 20d2 of the first rectangular hole 20d. Preferably, the clearance is designed to be narrow enough to allow the upper projection 6b to be easily inserted (i.e., non-press-fit insertion) into the first rectangular hole 20d even in the case of dimensional dispersion of the upper projection 6b and / or the first rectangular hole 20d. For example, in the case where the front projection in the projection 2j of the upper rail 2 (see Figure 3 ) mechanically collides with the front tongue in the tongue 1k of the lower rail 1 and thereby adjusts the stroke range of the upper rail 2 relative to the lower rail 1, the front surface 6b3 of the upper projection 6b compresses the front wall 7d of the elastic member 7 and deforms the front wall. This deformation of the elastic member 7 gradually narrows the clearance between the front surface 6b3 of the upper projection 6b and the front end surface 20d1 of the first rectangular hole 20d, and finally brings the front surface 6b3 of the upper projection 6b into contact with the front end surface 20d1 of the first rectangular hole 20d. This stops the deformation of the elastic member 7. In the case where the rear projection in the projection 2j of the upper rail 2 mechanically collides with the rear tongue in the tongue 1k of the lower rail 1, the clearance between the rear surface 6b4 of the upper projection 6b and the rear end surface 20d2 of the first rectangular hole 20d gradually narrows, and then the rear surface 6b4 of the upper projection 6b comes into contact with the rear end surface 20d2 of the first rectangular hole 20d. Therefore, designing the clearance to be narrow can reduce the displacement amount of the nut 6 in the vehicle front-rear direction.

[0073] The first bracket 20 and the second bracket 21 cover four surfaces (i.e., the upper, lower, front, and rear surfaces) of the nut 6 from the outside of the elastic member 7. Specifically, as Figure 8 shown, the first upper wall 20a of the first bracket 20 and the second upper wall 21a of the second bracket 21 cover the upper and lower surfaces of the nut 6 from the outside of the elastic member 7 (i.e., in this embodiment, the upper surface 6d1 of the right projection 6d, the upper surface 6e1 of the left projection 6e, the lower surface 6d2 of the right projection 6d, and the lower surface 6e2 of the left projection 6e). A pair of first walls 20b of the first bracket 20 cover the front and rear surfaces of the nut 6 from the outside of the elastic member 7 (i.e., the front surface 6d3 of the right projection 6d, the front surface 6e3 of the left projection 6e, the rear surface 6d4 of the right projection 6d, the rear surface 6d4 of the right projection 6d, and the rear surface 6e4 of the left projection 6e).

[0074] The length of the elastic member 7 in the vehicle front-rear direction corresponds to the sum of the length of the second upper wall 21a of the second bracket 21 in the vehicle front-rear direction and the lengths of two circular portions R4 (i.e., the portions formed by bending a metal plate) in the vehicle front-rear direction. This sum is equal to the length in the vehicle front-rear direction between the outer surfaces of a pair of second walls 21b of the second bracket 21.

[0075] Each of a pair of second walls 21b faces a corresponding one of a pair of first walls 20b of the first bracket 20.

[0076] A pair of second mounting walls 21c of the second bracket 21 face corresponding mounting walls of a pair of first mounting walls 20c of the first bracket 20. As Figure 7 shown, a second mounting hole 21f facing the pair of second mounting walls 21c and a first mounting hole 20f of the first mounting wall 20c are vertically aligned with each other, and are aligned with corresponding track-side mounting holes 1m formed in the bottom wall 1a of the lower track 1. A fastener 22 is inserted into the first mounting hole 20f, the second mounting hole 21f, and the track-side mounting hole 1m and caulked. Thus, the overlapping first mounting wall 20c and second mounting wall 21c are mounted to the bottom wall 1a of the lower track 1.

[0077] As described above, when viewed in a cross-section perpendicular to the front-rear direction, the entire contour of the nut 6 has a cross shape. The cross shape of the nut 6 is formed by the combination of the following parts: an upper projection 6b and a lower projection 6c, which are symmetric in the vertical direction over the entire internal thread hole 6a; a right projection 6d and a left projection 6e, which are symmetric in the left-right direction over the entire internal thread hole 6a. For example, the cross-shaped contour can be relatively easily formed by simply deforming the outer periphery of a rectangular rod block through stamping. Compared with the case where projections are formed on the surface of the nut 6 facing the first bracket 20, this helps to simplify the shape of the nut 6, improve the workability of the nut 6, and reduce the manufacturing cost of the nut 6.

[0078] According to an embodiment of the present application, the elastic member 7 is formed into a rectangular box, which includes: a ceiling wall 7a covering the upper surface of the nut 6; and a rectangular tubular wall 7b extending from the edge of the ceiling wall 7a and covering four surfaces (i.e., the right, left, upper, and lower surfaces) of the nut 6. The ceiling wall 7a includes a ceiling wall rectangular hole 7c. The front wall 7d and the rear wall 7e of the rectangular tubular wall 7b respectively include a first damper through-hole 7h and a second damper through-hole 7i. Thus, the elastic member 7 can be produced simply by forming a relatively simple rectangular box and forming three holes, namely, the ceiling wall rectangular hole 7c, the first damper through-hole 7h, and the second damper through-hole 7i, by molding with a rubber material in the rectangular box. This can simplify the shape of the nut 6, improve the workability of the nut 6, and reduce the manufacturing cost of the nut 6. In addition, since the nut 6 can be installed by simply inserting the nut 6 into the elastic member 7 having a simple rectangular box shape through the opening of the rectangular tubular wall 7b, the above features also facilitate the installation of the nut 6 onto the elastic member 7.

[0079] According to an embodiment of the present application, the nut 6 can move in the vertical direction relative to the elastic member 7 that provides an elastic force. The nut 6 moves in the vertical direction to align the axis of the internal thread hole 6a of the nut 6 with the axis of the screw shaft 3. This can suppress the noise and vibration generated due to the rotation of the screw shaft 3.

[0080] The upper protrusion 6b extends through the first rectangular hole 20d of the first upper wall 20a of the first bracket 20, and the lower protrusion 6c extends through the second rectangular hole 21d of the second upper wall 21a of the second bracket 21. This enables the upper protrusion 6b to contact the front end surface 20d1 and the rear end surface 20d2 of the first rectangular hole 20d and enables the lower protrusion 6c to contact the front end surface 21d1 and the rear end surface 21d2 of the second rectangular hole 21d when the screw shaft 3 continues to rotate after the upper track 2 collides with and stops at the lower track 1. This suppresses the excessive compression of the elastic member 7, suppresses the biting of the screw shaft 3 and the elastic member 7, thereby reducing the force required for the reverse operation of the screw shaft 3 and reducing noise and vibration.

[0081] As described above, the embodiment of the present application simplifies the shapes of the nut 6 and the elastic member 7, improves their machinability, but does not reduce the function of adjusting the axis of the screw shaft 3 and the axis of the internal thread hole 6a of the nut 6.

[0082] According to an embodiment of the present application, the cross-sectional shape of the nut 6 is symmetric in the vertical direction and the vehicle front-rear direction. The first rectangular hole 20d of the first bracket 20 and the second rectangular hole 21d of the second bracket 21 are equal in length along the vehicle front-rear direction and are the same in position along the vehicle front-rear direction. Therefore, the upper protrusion 6b and the lower protrusion 6c of the nut 6 are identical in shape to each other. This allows the lower protrusion 6c and the upper protrusion 6b to appropriately contact the first rectangular hole 20d and the second rectangular hole 21d respectively even when the lower protrusion 6c is inserted into the first rectangular hole 20d and the upper protrusion 6b is inserted into the second rectangular hole 21d. This can avoid misinstalling the nut 6 onto the first bracket 20 and the second bracket 21.

[0083] In addition, the embodiment of the present application allows the installation of the nut 6 by inserting the upper protrusion 6b and the lower protrusion 6c into the first rectangular hole 20d and the second rectangular hole 21d, thus eliminating the need to strictly determine the position of the nut 6 relative to the first bracket 20 and the second bracket 21. This facilitates the insertion operation of the nut 6.

[0084] According to an embodiment of the present application, the nut 6 is inserted into the rectangular tubular wall 7b so as not to form a gap extending in the vehicle front-rear direction and a gap extending in the left-right direction. This enables the elastic member 7 to moderately hold the nut 6, thereby suppressing the wobbling of the nut 6 relative to the elastic member 7 and the normal vibration of the nut 6.

[0085] The upper projection 6b is disposed inside the first rectangular hole 20d such that a gap is provided between the upper projection 6b and each of the front end surface 20d1 and the rear end surface 20d2 of the first rectangular hole 20d. Similarly, the lower projection 6c is disposed inside the second rectangular hole 21d such that a gap is provided between the lower projection 6c and each of the front end surface 21d1 and the rear end surface 21d2 of the second rectangular hole 21d. In the case where the upper rail 2 and the lower rail 1 undergo a mechanical collision such that the upper projection 6b contacts the front end surface 20d1 of the first rectangular hole 20d, the front wall 7d of the elastic member 7 is compressed until the gap between the upper projection 6b and the front end surface 20d1 is eliminated. Therefore, by appropriately setting the size of the gap, excessive compression of the elastic member 7 can be suppressed.

[0086] According to an embodiment of the present application, a gap CL is formed between the right projection 6d and the left projection 6e and the upper surface 21a1 of the first upper wall 20a (i.e., the ceiling wall 7a of the elastic member 7) of the first bracket 20 and the second upper wall 21a of the second bracket 21. The nut 6 can move in the vertical direction between the first upper wall 20a of the first bracket 20 and the second upper wall 21a of the second bracket 21. Therefore, the nut 6 is set to be able to move in the vertical direction within a range corresponding to the vertical length of the gap CL without compressing the elastic member 7. The gap CL absorbs the vertical dispersion of the lower rail 1 and the upper rail 2 caused by assembly errors and the like. Therefore, the nut 6 aligns the axis of the screw shaft 3 and the axis of the internal thread hole 6a of the nut 6 through the vertical movement of the gap CL. This can suppress the noise and vibration generated due to the rotation of the screw shaft 3.

[0087] The embodiment of the present application illustrates the case where the screw shaft 3 is rotatably mounted on the upper rail 2. However, the present invention is not limited thereto. The screw shaft 3 can be rotatably mounted on the lower rail 1 instead of the upper rail 2.

[0088] The embodiment of the present application illustrates the case where the nut 6 is mounted on the lower rail 1 via the elastic member 7 and the bracket 8. However, the present invention is not limited thereto. The nut 6 can be mounted on the upper rail 2 via the elastic member 7 and the bracket 8 instead of the lower rail 1.

[0089] The features of the embodiments of the present disclosure are summarized below.

[0090] According to one aspect of the present disclosure, a seat sliding device for a vehicle includes: a lower rail extending in the longitudinal direction of the vehicle; an upper rail configured to be relatively movable with respect to the lower rail in the longitudinal direction of the lower rail; a screw shaft mounted on a first one of the lower rail and the upper rail so as to be rotatable and extending in the longitudinal direction of the lower rail; a nut mounted on a second one of the lower rail and the upper rail, including a screw hole extending through the nut in the front-rear direction and threadedly connected to the screw shaft; an elastic member having a rectangular box shape and including: a ceiling wall covering the upper surface of the nut and including a ceiling wall rectangular hole; a rectangular tubular wall extending from an edge of the ceiling wall and covering the front, rear, right, and left sides of the nut; and a through hole overlapping the screw hole of the nut in the front-rear direction; and a bracket supporting the elastic member so as to cover the front, rear, upper, and lower surfaces of the nut from the outside of the elastic member. The bracket includes a first bracket and a second bracket. The first bracket includes: a first upper wall facing the upper surface of the nut and including a first rectangular hole; a pair of first walls extending downward from both ends of the first upper wall in the front-rear direction and respectively facing the front and rear of the nut; and a pair of first mounting walls extending in the front-rear direction from the lower ends of the pair of first walls so as to extend away from each other. The second bracket includes: a second upper wall facing the lower surface of the nut and including a second rectangular hole; a pair of second walls extending downward from both ends of the second upper wall in the front-rear direction and respectively facing the pair of first walls of the first bracket; and a pair of second mounting walls extending in the front-rear direction from the lower ends of the pair of second walls so as to extend away from each other and being mounted on the bottom wall of the lower rail together with the pair of first mounting walls of the first bracket. The nut has a cross-shaped shape when viewed in a cross-section in a direction perpendicular to the axis of the screw shaft, and includes: an upper protrusion extending through the ceiling wall rectangular hole of the ceiling wall of the elastic member and through the first rectangular hole of the first upper wall of the first bracket; and a lower protrusion protruding downward through an opening of the elastic member and extending through the second rectangular hole of the second upper wall of the second bracket.

[0091] In addition to the above one aspect of the present disclosure, the nut is formed to be symmetric in the front-rear direction and symmetric in the vertical direction. The lengths of the first rectangular hole of the first bracket and the second rectangular hole of the second bracket in the front-rear direction are equal to each other, and the positions in the front-rear direction are the same.

[0092] In addition to the above - mentioned aspect of the present disclosure, the nut is inserted into the rectangular tubular wall of the elastic member, and there is no gap extending in the front - rear direction or in the left - right direction. Each of the first rectangular hole of the first bracket and the second rectangular hole of the second bracket includes a front end face and a rear end face that are respectively positioned on the front side and the rear side in the front - rear direction. The upper protrusion of the nut is disposed inside the first rectangular hole so as to form a gap between the upper protrusion and the front surface of the first rectangular hole and a gap between the upper protrusion and the rear surface of the first rectangular hole. The lower protrusion of the nut is disposed inside the second rectangular hole so as to form a gap between the lower protrusion and the front surface of the second rectangular hole and a gap between the lower protrusion and the rear surface of the second rectangular hole.

[0093] In addition to the above - mentioned aspect of the present disclosure, the distance between the upper surface of the nut excluding the upper protrusion and the lower surface of the nut excluding the lower protrusion is less than the distance between the lower surface of the ceiling wall of the elastic member and the upper surface of the second upper wall of the second bracket, wherein the ceiling wall of the elastic member is provided below the first upper wall of the first bracket. The nut can move vertically between the ceiling wall of the elastic member and the second upper wall of the second bracket. The heights of the upper protrusion and the lower protrusion of the nut are set so as to prevent the upper protrusion and the lower protrusion from coming out of the first rectangular hole of the first bracket and the second rectangular hole of the second bracket even when the nut moves vertically.

[0094] The entire content of Japanese Patent Application No. 2023 - 200397 filed on November 28, 2023 is incorporated herein by reference.

Claims

1. A seat sliding device for a vehicle, the seat sliding device comprising: a lower rail extending in a front-rear direction of the vehicle; an upper rail configured to be relatively movable with respect to the lower rail along a longitudinal direction of the lower rail; a screw shaft mounted to a first rail of the lower rail and the upper rail so as to be rotatable and extending in a longitudinal direction of the lower rail; a nut mounted on a second one of the lower rail and the upper rail, including a screw hole extending through the nut in a front-to-rear direction and being threadedly connected to the screw shaft; an elastic member having a rectangular box shape and comprising: a ceiling wall covering an upper side of the nut and comprising a ceiling wall rectangular hole; a rectangular tubular wall extending from an edge of the ceiling wall and covering the front, rear, right and left sides of the nut; and a through hole overlapping the screw hole of the nut in a front-to-rear direction; and a bracket supporting the elastic member so as to cover the front, rear, top and bottom of the nut from the outside of the elastic member, in: The bracket comprises a first bracket and a second bracket; The first bracket includes: a first upper wall, the first upper wall faces the upper side of the nut and includes a first rectangular hole; a pair of first walls, the pair of first walls extend downward from both ends of the first upper wall in the front-to-back direction and face the front and rear of the nut respectively; and a pair of first mounting walls, the pair of first mounting walls extend from the lower ends of the pair of first walls in the front-to-back direction so as to extend away from each other; The second bracket includes: a second upper wall, the second upper wall faces the lower side of the nut and includes a second rectangular hole; a pair of second walls, the pair of second walls extend downward from both ends of the second upper wall in the front-to-back direction and respectively face the pair of first walls of the first bracket; and a pair of second mounting walls, the pair of second mounting walls extend from the lower ends of the pair of second walls in the front-to-back direction so as to extend away from each other and are mounted on the bottom wall of the lower rail together with the pair of first mounting walls of the first bracket; and The nut has a cross shape when viewed in a cross section in a direction perpendicular to the axis of the screw shaft, and includes: an upper protrusion extending through the rectangular hole of the ceiling wall of the ceiling wall of the elastic member and through the first rectangular hole of the first upper wall of the first bracket; and a lower protrusion protruding downward through the opening surface of the elastic member and extending through the second rectangular hole of the second upper wall of the second bracket.

2. The seat sliding device according to claim 1, wherein: The nut is shaped to be symmetrical in the front-rear direction and symmetrical in the vertical direction; and The first rectangular hole of the first bracket and the second rectangular hole of the second bracket have lengths in the front-rear direction equal to each other and positions in the front-rear direction identical to each other.

3. The seat sliding device according to claim 1, wherein: The nut is inserted into the rectangular tubular wall of the elastic member without a gap extending in the front-to-rear direction or a gap extending in the left-to-right direction; Each of the first rectangular hole of the first bracket and the second rectangular hole of the second bracket includes a front end surface and a rear end surface positioned at the front side and the rear side, respectively, in the front-to-rear direction; The upper protrusion of the nut is disposed inside the first rectangular hole so as to form a gap between the upper protrusion and the front end surface of the first rectangular hole and a gap between the upper protrusion and the rear end surface of the first rectangular hole; and The lower protrusion of the nut is disposed inside the second rectangular hole so as to form a gap between the lower protrusion and a front end surface of the second rectangular hole and a gap between the lower protrusion and a rear end surface of the second rectangular hole.

4. The seat sliding device according to claim 1, wherein: The distance between the upper surface of the nut excluding the upper protrusion and the lower surface of the nut excluding the lower protrusion is smaller than the distance between the lower surface of the ceiling wall of the elastic member and the upper surface of the second upper wall of the second bracket, wherein the ceiling wall of the elastic member is disposed below the first upper wall of the first bracket; The nut is movable in a vertical direction between the ceiling wall of the elastic member and the second upper wall of the second bracket; and The upper and lower protrusions of the nut have heights set to prevent the upper and lower protrusions from coming out of the first and second rectangular holes of the first and second brackets even when the nut is vertically moved.

Images