Electric slide rail and vehicle seat equipped with electric slide rail

Abstract

To provide: an electrically powered slide rail that can operate smoothly; and a vehicle seat capable of achieving smooth sliding movement.SOLUTION: An electrically powered slide rail 1 includes a rail 11 having a channel-shaped cross section and extending in a fore and aft direction, a slider 12 received by the rail and slidably engaging the rail, a screw assembly 35 including a screw member 38, 39 supported by the slider so as to be rotatable around the fore and aft direction, an electric motor 36 supported by the slider and configured to rotate the screw member, and a screw engaging portion 57, 58 formed in the rail so as to extend in the fore and aft direction and engage the screw member. A vehicle seat 2 comprises the electrically powered slide rail 1, where the rail 11 is connected to a floor 3 of a vehicle, and the slider is connected to a seat cushion 5.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electric slide rail and a vehicle seat equipped with an electric slide rail. [Background technology]

[0002] An electric slide rail for an automobile is known, which includes a lower rail, an upper rail, a worm provided between the lower rail and the upper rail, an electric motor for driving the worm, and worm screwing means provided on both the upper rail and the lower rail for screwing with the worm (for example, Patent Document 1). Four worms are provided, with the upper two engaging with pitch grooves provided on the underside of the upper rail and the lower two engaging with pitch grooves provided on the lower rail. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 4-310437 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the worm and the electric motor are not fixed to either the lower rail or the upper rail, the worm is likely to tilt relative to the lower rail or the upper rail, which may impede the rotation of the worm. As a result, the operation of the electric slide rail may be impeded. Furthermore, the impeded operation of the electric slide rail may easily cause abnormal noise, rattle, etc.

[0005] In view of the above background, an object of the present invention is to provide an electric slide rail that can operate smoothly, and also to provide a vehicle seat that can slide smoothly. [Means for solving the problem]

[0006] In order to solve the above problem, one aspect of the present invention is an electric slide rail (1) comprising: a rail (11) having a groove-shaped cross section and extending in a forward-backward direction; a slider (12) received in the rail and slidably engaging with the rail; a screw assembly (35) including screw members (38, 39) supported on the slider so as to be rotatable around the forward-backward direction; an electric motor (36) supported on the slider and rotating the screw members; and screw engagement portions (57, 58) formed on the rail extending in the forward-backward direction to engage with the screw members.

[0007] According to this aspect, since the motor and the screw assembly are fixed to the slider, the screw member is prevented from falling relative to the screw engagement portion. Therefore, the screw member can engage with the screw engagement portion at an appropriate angle, allowing for smooth rotation of the screw member. As a result, an electric slide rail that can operate smoothly can be provided. Furthermore, since the electric motor is attached to the slider that is received in the rail, the external dimensions of the electric rail device can be reduced. The shaft for transmitting the rotational force of the electric motor to the screw member can be shortened. Furthermore, since the screw member rotatably supported on the slider engages with the screw engagement portion provided on the rail, backlash (tolerance) can be reduced compared to a configuration in which the screw engagement portion is provided on both the slider and the rail and the screw member engages with screw engagement portions provided on both the slider and the rail. Furthermore, since the electric motor and the screw assembly are provided on the slider, the movement stroke of the slider can be easily extended by extending the rail.

[0008] In addition, in the above aspect, the rail may have a first side wall (17) and a second side wall (17) facing each other, the screw engagement portion may have a first screw engagement portion (57) formed on the first side wall and a second screw engagement portion (58) formed on the second side wall, and the screw member may have a first screw member (38) that engages with the first screw engagement portion and a second screw member (39) that engages with the second screw engagement portion, which are arranged in parallel with each other between the first screw engagement portion and the second screw engagement portion.

[0009] According to this aspect, because the screw assembly has two screw members, the first screw member and the second screw member, the screw assembly can be miniaturized while engaging with both the first screw engagement portion and the second screw engagement portion. Furthermore, because the direction of the reaction force that the first screw member receives from the first screw engagement portion is opposite to the direction of the reaction force that the second screw member receives from the second screw engagement portion, the first screw member and the first screw engagement portion are reliably engaged, and the second screw member and the second screw engagement portion are reliably engaged. Furthermore, because the first screw engagement portion and the second screw engagement portion are formed on the first side wall and the second side wall, which face each other, foreign matter is less likely to remain in the first screw engagement portion and the second screw engagement portion.

[0010] In addition, in the above aspect, the screw assembly has a gear case (41) that rotatably supports the first screw member and the second screw member and a first bracket (42) for supporting the gear case on the slider, and the gear case has an opening (48) for exposing the first screw member and the second screw member to the side.

[0011] According to this aspect, it is possible to easily assemble the screw assembly having the first screw member and the second screw member to the slider.

[0012] In addition, in the above aspect, the first bracket may have a first connecting portion (42A) extending forward from the front of the gear case and a second connecting portion (42B) extending rearward from the rear of the gear case, and may be connected to the slider at the first connecting portion and the second connecting portion.

[0013] According to this aspect, the first bracket can support the first gear case with good stability.

[0014] In addition, in the above aspect, the first bracket may be an integral metal member including a support portion (42C) extending from the first connecting portion to the second connecting portion, and the gear case may be disposed between the slider and the support portion.

[0015] According to this aspect, the closed structure formed by the slider and the first bracket can stably support the gear case.

[0016] In addition, in the above aspect, the slider may further include a second bracket (51) for supporting the electric motor, connected to the front or rear of the first bracket, and the second bracket may cantilever-support the end of the electric motor on the side of the screw member.

[0017] According to this aspect, the electric motor is cantilevered by the second bracket, allowing the electric motor to tilt slightly relative to the screw assembly, thereby allowing for misalignment between the rotation shaft of the electric motor and the screw assembly.

[0018] In addition, in the above aspect, the slider is formed in a groove shape having a base portion (25) and a third side wall (26) and a fourth side wall (26) extending from the base portion toward the bottom side of the rail, the third side wall faces the first side wall, the fourth side wall faces the second side wall, the second bracket is connected to the base portion, and the electric motor is arranged between the third side wall and the fourth side wall.

[0019] According to this aspect, the electric motor is disposed inside the slider, and the external dimensions of the electric slide rail can be reduced.

[0020] In addition, in the above aspect, the first screw member may pass through an opening (55) formed in the third side wall and engage with the first screw engagement portion, and the second screw member may pass through an opening formed in the fourth side wall and engage with the second screw engagement portion.

[0021] According to this aspect, the screw assembly can be disposed in a position close to the electric motor, which results in a shorter shaft that transmits the driving force of the electric motor to the screw assembly, thereby enabling smoother rotation of the screw member.

[0022] In addition, in the above aspect, the gear case has a pair of front and rear first bearing portions (45) that rotatably support the front and rear ends of the first screw member, a pair of front and rear second bearing portions (46) that rotatably support the front and rear ends of the second screw member, and a pair of front and rear third bearing portions (47) that rotatably support a drive shaft (43) connected to a rotating shaft (36A) of the electric motor, the drive shaft has a pair of front and rear drive gears (43A), the first screw member has a pair of front and rear first gears (38B) that mesh with the pair of drive gears respectively, and the second screw member has a pair of front and rear second gears (39B) that mesh with the pair of drive gears respectively.

[0023] According to this aspect, the rotational force of the electric motor can be reliably transmitted to the first screw member and the second screw member, and the first screw member, the second screw member, and the drive shaft can be positioned stably and accurately.

[0024] In the above aspect, the rotary shaft and the drive shaft of the electric motor may be connected to each other via a reducer.

[0025] According to this aspect, the rotation of the drive shaft can be decelerated to generate the torque required for the first screw member and the second screw member.

[0026] In addition, in the above aspect, the first side wall and the second side wall may have protrusions (22) that protrude toward each other and extend in the front-to-rear direction, and the screw engagement portion may include a plurality of engagement holes (59) formed in the protrusions in a line in the front-to-rear direction.

[0027] According to this aspect, the amount of engagement between the thread engagement portion and the teeth of the screw member can be increased.

[0028] In the above aspect, the rail may be provided with a conductive strip (62) extending forward and backward and connected to a power source inside, and an electrical insulating plate (63) may be provided between the rail and the conductive strip, and the electric motor may have a conductive contact terminal (64) that slides against the conductive strip.

[0029] According to this aspect, it is possible to omit the harness for supplying power to the electric motor.

[0030] In the above aspect, the electrical insulating plate may have an extension (63A) at its side edge that is bent inward and above the conductive strip and faces the conductive strip across a gap, and the contact terminal may extend between the extension and the conductive strip.

[0031] According to this aspect, it is possible to prevent foreign matter from coming into contact with the power supply plate.

[0032] Another aspect of the present invention is a vehicle seat (2) equipped with the above-mentioned electric slide rail, wherein the rail is connected to a floor (3) of the vehicle and the slider is connected to a seat cushion (5).

[0033] According to this aspect, it is possible to provide a vehicle seat that can slide smoothly.

[0034] In the above aspect, the rail may be received in a rail groove (4) provided in the floor.

[0035] According to this aspect, the rail can be disposed in the rail groove so that the rail does not protrude from the floor. [Effects of the Invention]

[0036] One aspect of the present invention is an electric slide rail (1) comprising: a rail (11) having a groove-shaped cross section and extending in a forward-backward direction; a slider (12) received in the rail and slidably engaging with the rail; a screw assembly (35) including screw members (38, 39) supported on the slider so as to be rotatable around the forward-backward direction; an electric motor (36) supported on the slider and rotating the screw members; and screw engagement portions (57, 58) formed on the rail extending in the forward-backward direction to engage with the screw members.

[0037] According to this aspect, since the motor and the screw assembly are fixed to the slider, the screw member is prevented from falling relative to the screw engagement portion. Therefore, the screw member can engage with the screw engagement portion at an appropriate angle, allowing for smooth rotation of the screw member. As a result, an electric slide rail that can operate smoothly can be provided. Furthermore, since the electric motor is attached to the slider that is received in the rail, the external dimensions of the electric rail device can be reduced. The shaft for transmitting the rotational force of the electric motor to the screw member can be shortened. Furthermore, since the screw member rotatably supported on the slider engages with the screw engagement portion provided on the rail, backlash (tolerance) can be reduced compared to a configuration in which the screw engagement portion is provided on both the slider and the rail and the screw member engages with screw engagement portions provided on both the slider and the rail. Furthermore, since the electric motor and the screw assembly are provided on the slider, the movement stroke of the slider can be easily extended by extending the rail.

[0038] In addition, in the above aspect, the rail may have a first side wall (17) and a second side wall (17) facing each other, the screw engagement portion may have a first screw engagement portion (57) formed on the first side wall and a second screw engagement portion (58) formed on the second side wall, and the screw member may have a first screw member (38) that engages with the first screw engagement portion and a second screw member (39) that engages with the second screw engagement portion, which are arranged in parallel with each other between the first screw engagement portion and the second screw engagement portion.

[0039] According to this aspect, because the screw assembly has two screw members, the first screw member and the second screw member, the screw assembly can be miniaturized while engaging with both the first screw engagement portion and the second screw engagement portion. Furthermore, because the direction of the reaction force that the first screw member receives from the first screw engagement portion is opposite to the direction of the reaction force that the second screw member receives from the second screw engagement portion, the first screw member and the first screw engagement portion are reliably engaged, and the second screw member and the second screw engagement portion are reliably engaged. Furthermore, because the first screw engagement portion and the second screw engagement portion are formed on the first side wall and the second side wall, which face each other, foreign matter is less likely to remain in the first screw engagement portion and the second screw engagement portion.

[0040] In addition, in the above aspect, the screw assembly has a gear case (41) that rotatably supports the first screw member and the second screw member and a first bracket (42) for supporting the gear case on the slider, and the gear case has an opening (48) for exposing the first screw member and the second screw member to the side.

[0041] According to this aspect, it is possible to easily assemble the screw assembly having the first screw member and the second screw member to the slider.

[0042] In addition, in the above aspect, the first bracket may have a first connecting portion (42A) extending forward from the front of the gear case and a second connecting portion (42B) extending rearward from the rear of the gear case, and may be connected to the slider at the first connecting portion and the second connecting portion.

[0043] According to this aspect, the first bracket can support the first gear case with good stability.

[0044] In addition, in the above aspect, the first bracket may be an integral metal member including a support portion (42C) extending from the first connecting portion to the second connecting portion, and the gear case may be disposed between the slider and the support portion.

[0045] According to this aspect, the closed structure formed by the slider and the first bracket can stably support the gear case.

[0046] In addition, in the above aspect, the slider may further include a second bracket (51) for supporting the electric motor, connected to the front or rear of the first bracket, and the second bracket may cantilever-support the end of the electric motor on the side of the screw member.

[0047] According to this aspect, the electric motor is cantilevered by the second bracket, allowing the electric motor to tilt slightly relative to the screw assembly, thereby allowing for misalignment between the rotation shaft of the electric motor and the screw assembly.

[0048] In addition, in the above aspect, the slider is formed in a groove shape having a base portion (25) and a third side wall (26) and a fourth side wall (26) extending from the base portion toward the bottom side of the rail, the third side wall faces the first side wall, the fourth side wall faces the second side wall, the second bracket is connected to the base portion, and the electric motor is arranged between the third side wall and the fourth side wall.

[0049] According to this aspect, the electric motor is disposed inside the slider, and the external dimensions of the electric slide rail can be reduced.

[0050] In addition, in the above aspect, the first screw member may pass through an opening (55) formed in the third side wall and engage with the first screw engagement portion, and the second screw member may pass through an opening formed in the fourth side wall and engage with the second screw engagement portion.

[0051] According to this aspect, the screw assembly can be disposed in a position close to the electric motor, which results in a shorter shaft that transmits the driving force of the electric motor to the screw assembly, thereby enabling smoother rotation of the screw member.

[0052] In addition, in the above aspect, the gear case has a pair of front and rear first bearing portions (45) that rotatably support the front and rear ends of the first screw member, a pair of front and rear second bearing portions (46) that rotatably support the front and rear ends of the second screw member, and a pair of front and rear third bearing portions (47) that rotatably support a drive shaft (43) connected to a rotating shaft (36A) of the electric motor, the drive shaft has a pair of front and rear drive gears (43A), the first screw member has a pair of front and rear first gears (38B) that mesh with the pair of drive gears respectively, and the second screw member has a pair of front and rear second gears (39B) that mesh with the pair of drive gears respectively.

[0053] According to this aspect, the rotational force of the electric motor can be reliably transmitted to the first screw member and the second screw member, and the first screw member, the second screw member, and the drive shaft can be positioned stably and accurately.

[0054] In the above aspect, the rotary shaft and the drive shaft of the electric motor may be connected to each other via a reducer.

[0055] According to this aspect, the rotation of the drive shaft can be decelerated to generate the torque required for the first screw member and the second screw member.

[0056] In addition, in the above aspect, the first side wall and the second side wall may have protrusions (22) that protrude toward each other and extend in the front-to-rear direction, and the screw engagement portion may include a plurality of engagement holes (59) formed in the protrusions in a line in the front-to-rear direction.

[0057] According to this aspect, the amount of engagement between the thread engagement portion and the teeth of the screw member can be increased.

[0058] In the above aspect, the rail may be provided with a conductive strip (62) extending forward and backward and connected to a power source inside, and an electrical insulating plate (63) may be provided between the rail and the conductive strip, and the electric motor may have a conductive contact terminal (64) that slides against the conductive strip.

[0059] According to this aspect, it is possible to omit the harness for supplying power to the electric motor.

[0060] In the above aspect, the electrical insulating plate may have an extension (63A) at its side edge that is bent inward and above the conductive strip and faces the conductive strip across a gap, and the contact terminal may extend between the extension and the conductive strip.

[0061] According to this aspect, it is possible to prevent foreign matter from coming into contact with the power supply plate.

[0062] Another aspect of the present invention is a vehicle seat (2) equipped with the above-mentioned electric slide rail, wherein the rail is connected to a floor (3) of the vehicle and the slider is connected to a seat cushion (5).

[0063] According to this aspect, it is possible to provide a vehicle seat that can slide smoothly.

[0064] In the above aspect, the rail may be received in a rail groove (4) provided in the floor.

[0065] According to this aspect, the rail can be disposed in the rail groove so that the rail does not protrude from the floor. [Brief explanation of the drawings]

[0066] [Figure 1] 1 is a diagram illustrating a vehicle seat equipped with an electric slide rail according to an embodiment of the present invention; [Figure 2] Perspective view of the electric slide rail [Figure 3] Cross-sectional view of the electric slide rail (cross-sectional view III-III in Figure 5) [Figure 4] Rail cross section [Figure 5] FIG. 1 is a perspective view of a slider, with a portion cut away; [Figure 6] Cross section of an electric slide rail [Figure 7] FIG. 1 is a perspective view of the screw assembly without the first bracket. [Figure 8] FIG. 1 is a perspective view of a screw assembly with the first bracket and outer case omitted; [Figure 9] Cross-sectional view of the electric slide rail (cross-sectional view IX-IX in Figure 5) [Figure 10] FIG. 10 is a perspective view showing engagement between the first and second screw members and the first and second screw engagement portions; [Figure 11] FIG. 10 is a perspective view of an electric slide rail equipped with a power supply device according to a modified example. [Figure 12] 1A and 1B are explanatory diagrams showing the state of the power supply device when the slider is in front of the rail and when the slider is in rear of the rail; [Figure 13] Cross section of the cover piece [Figure 14] 10 is a cross-sectional view of a slider according to another embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0067] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. An electric slide rail has a rail and a slider that can slide relative to the rail. The rail is coupled to a first structure, and the slider is coupled to a second structure. The electric slide rail moves the second structure relative to the first structure as the slider moves relative to the rail. The electric slide rail is installed, for example, between a floor and a seat of a vehicle and moves the seat relative to the floor. The electric slide rail is also installed between a base and a work holder and moves the work holder relative to the base.

[0068] Hereinafter, an embodiment of an electric slide rail 1 and a vehicle seat 2 equipped with the electric slide rail 1 will be described with reference to the drawings. As shown in FIG. 1 , the vehicle seat 2 has at least one electric slide rail 1 on its lower portion, and is connected to a floor 3 of the vehicle by the electric slide rail 1. The vehicle seat 2 has a seat cushion 5 that supports the buttocks of an occupant, and a seat back 6 that extends upward from the rear of the seat cushion 5 and supports the back of the occupant. The electric slide rail 1 is provided between the floor 3 and the seat cushion 5, and supports the seat cushion 5 so that it can slide relative to the floor 3. The vehicle seat 2 preferably has a pair of electric slide rails 1.

[0069] As shown in FIG. 2 , the electric slide rail 1 has a rail 11 extending in the front-rear direction and a slider 12 slidably engaged with the rail 11. The extension direction of the rail 11 is defined as the front-rear direction. The extension direction of the rail 11 may or may not coincide with the front-rear direction of the vehicle. In other words, the extension direction of the rail 11 does not limit the installation direction on the vehicle. In this embodiment, the extension direction of the rail 11 coincides with the front-rear direction of the vehicle. In this embodiment, the slider 12 is provided above the rail 11. Therefore, the rail 11 may be referred to as a lower rail, and the slider 12 may be referred to as an upper rail.

[0070] 3 and 4, the rail 11 has a groove-shaped cross section. Specifically, the rail 11 has a rail bottom wall 14 with faces facing up and down, left and right rail outer walls 15 that extend upward from the left and right edges of the rail bottom wall 14 and have faces facing left and right, left and right rail upper walls 16 that extend toward each other from the upper ends of the left and right rail outer walls 15 and have faces facing up and down, and left and right rail inner walls 17 that extend downward from the inner ends of the left and right rail upper walls 16 and have faces facing left and right. The left and right rail inner walls 17 correspond to the first side wall and second side wall in the claims.

[0071] The rail bottom wall 14, the left and right rail outer walls 15, the left and right rail upper walls 16, and the left and right rail inner walls 17 each extend in the front-to-rear direction. The left and right rail outer walls 15 and the left and right rail inner walls 17 extend parallel to each other and perpendicular to the rail bottom wall 14. The lower ends of the left and right rail inner walls 17 are spaced apart from the rail bottom wall 14. The rail 11 has a rail opening 19 at its upper part that extends in the front-to-rear direction. The rail opening 19 is defined by the left and right rail inner walls 17. The rail 11 may be formed by press-forming a metal plate. The left and right edge portions of the rail bottom wall 14 may have upwardly protruding steps 21. The left and right steps 21 extend in the front-to-rear direction and have flat upper surfaces.

[0072] The left and right rail inner walls 17 are each formed with a protrusion 22 that protrudes toward each other and extends in the front-to-rear direction. The cross section of the left and right protrusions 22 may be formed in an arc or trapezoid shape. Each protrusion 22 may be located in the middle of the corresponding rail inner wall 17 in the up-down direction. The upper and lower ends of the left and right rail inner walls 17 are located outward from the protrusions 22 to the left and right.

[0073] As shown in FIG. 3 , the slider 12 is disposed at the opening edge of the rail opening 19 and includes a plate-shaped base portion 25 with its surfaces facing up and down, left and right slider inner walls 26 extending downward from the left and right side edges of the base portion 25 toward the rail bottom wall 14, left and right slider lower walls 27 extending outward to the left and right from the lower ends of the left and right slider inner walls 26, respectively, and left and right slider outer walls 28 extending upward from the left and right outer ends of the left and right slider lower walls 27. The left and right slider inner walls 26 correspond to the third and fourth side walls in the claims. The base portion 25, the left and right slider inner walls 26, the left and right slider lower walls 27, and the left and right slider outer walls 28 extend forward and backward.

[0074] The slider 12 may be formed by fastening together a plurality of press-formed or roll-formed metal plates. In this embodiment, the slider 12 is composed of a first piece 12A constituting a base portion 25, a left slider inner wall 26, a left slider lower wall 27, and a left slider outer wall 28, and a second piece 12B constituting the base portion 25, a right slider inner wall 26, a right slider lower wall 27, and a right slider outer wall 28. The first piece 12A and the second piece 12B are overlapped and fastened together at their respective base portions 25 to form the slider 12. In another embodiment, the slider 12 may be formed from a single press-formed or roll-formed metal plate. The front-to-rear length of the slider 12 is set shorter than the front-to-rear length of the rail 11. The slider 12 is connected to the seat cushion 5 at the base portion 25.

[0075] The base portion 25 may be disposed above or below the left and right rail upper walls 16. The left and right slider inner walls 26 face left and right and face each other at a distance. The left and right slider inner walls 26 are disposed between the left and right rail inner walls 17. Each slider inner wall 26 faces the corresponding rail inner wall 17 on the left and right with a gap between them. Each slider lower wall 27 extends left and right, passing between the rail bottom wall 14 and the lower end of the corresponding rail 11 inner wall on the left and right. The outer wall of each slider 12 is disposed between the corresponding rail outer wall 15 and rail inner wall 17 on the left and right. A plurality of wheels 31 are rotatably supported on the outer surface of each slider outer wall 28 in the left and right direction. Each wheel 31 has a rotation axis that rotates left and right and is in contact with the rail bottom wall 14. In this embodiment, each wheel 31 is in contact with the upper surface of the step portion 21 of the rail bottom wall 14. The slider 12 can smoothly slide along the rail 11 by contacting the rail 11 via the wheels 31. With the above configuration, the slider 12 is received in the rail 11 and slidably engages with the rail 11. In other embodiments, the slider 12 may be supported on the rail 11 via a ball or roller bearing.

[0076] The left and right slider inner walls 26 are formed with recesses 33 that are recessed toward each other and extend in the front-to-rear direction. A protrusion is formed on the rear side of the recesses 33 of the slider inner walls 26. The cross section of the left and right recesses 33 as viewed from the front-to-rear direction may be formed in an arc shape or a trapezoid shape. Each recess 33 may be located in the middle of the corresponding slider inner walls 26 in the up-down direction. Each recess 33 is located in a position facing the protrusion 22 of the corresponding rail 11 on the left and right.

[0077] The slider 12 is formed by a base portion 25 and left and right slider inner walls 26 into a groove shape that opens toward the rail bottom wall 14, i.e., downward. As shown in Figures 5 and 6, a screw assembly 35 and an electric motor 36 are supported on the underside of the base portion 25. The screw assembly 35 includes screw members 38, 39 that are supported on the slider 12 and are rotatable around the front-to-rear direction. The electric motor 36 is supported on the slider 12 and rotates the screw members 38, 39.

[0078] As shown in FIGS. 8 and 10 , in this embodiment, the screw members 38 and 39 include a first screw member 38 and a second screw member 39. In other embodiments, the screw assembly 35 may include a single screw member. The first screw member 38 and the second screw member 39 have threads 38A and 39A on the outer circumferential surfaces of the longitudinally intermediate portions. The number of threads 38A and 39A may be determined based on the size of the electric slide rail 1 and the required strength of the electric slide rail 1 in the longitudinal direction. For example, the number of threads 38A and 39A may be increased to increase the required strength. As shown in FIGS. 5 and 6 , the screw assembly 35 includes a gear case 41 that rotatably supports the first screw member 38 and the second screw member 39 and a first bracket 42 that supports the gear case 41 on the slider 12.

[0079] 7 and 8, the gear case 41 is formed in the shape of a rectangular parallelepiped box that is long in the front-to-rear direction. The gear case 41 rotatably supports a first screw member 38, a second screw member 39, and a drive shaft 43 that is connected to a rotary shaft 36A of the electric motor 36. The first screw member 38, the second screw member 39, and the drive shaft 43 each extend in the front-to-rear direction and are arranged in parallel to one another in the gear case 41. The gear case 41 has a box-shaped outer case 41A that forms an outer shell, and a front support member 41B and a rear support member 41C that are supported at the front and rear ends of the outer case 41A. The front support member 41B and the rear support member 41C are provided with a pair of front and rear first bearing portions 45 that rotatably support the front and rear ends of the first screw member 38, a pair of front and rear second bearing portions 46 that rotatably support the front and rear ends of the second screw member 39, and a pair of front and rear third bearing portions 47 that rotatably support the drive shaft 43.

[0080] The first screw member 38 is disposed along the left side of the gear case 41, and the second screw member 39 is disposed along the right side of the gear case 41. The drive shaft 43 is disposed below the intermediate portion between the first screw member 38 and the second screw member 39. The drive shaft 43 has a drive gear 43A within the gear case 41. The first screw member 38 has a first gear 38B that meshes with the drive gear 43A. The second screw member 39 has a second gear 39B that meshes with the drive gear 43A. The drive gear 43A, the first gear 38B, and the second gear 39B may each be a spur gear. When the drive shaft 43 rotates, the first screw member 38 and the second screw member 39 rotate in the same direction. The first gear 38B and the second gear 39B may be symmetrical.

[0081] 5 and 6, the gear case 41 has a case opening 48 that is an opening for laterally exposing the first screw member 38 and the second screw member 39. The threads 38A of the first screw member 38 pass through the case opening 48 formed on the left side of the gear case 41 and protrude leftward. Similarly, the threads 39A of the second screw member 39 pass through the case opening 48 formed on the right side of the gear case 41 and protrude rightward. The case opening 48 is formed in the outer case 41A.

[0082] The first bracket 42 extends longitudinally and has a first connecting portion 42A at its front end and a second connecting portion 42B at its rear end. The first bracket 42 is connected to the underside of the base portion 25 of the slider 12 at the first connecting portion 42A and the second connecting portion 42B. The first bracket 42 has a support portion 42C extending from the first connecting portion 42A to the second connecting portion 42B. The first bracket 42 may be an integrated metal member including the first connecting portion 42A, the second connecting portion 42B, and the support portion 42C. The support portion 42C has a portion located below the first connecting portion 42A and the second connecting portion 42B. The support portion 42C allows the first bracket 42 to cooperate with the base portion 25 to form a closed structure. The gear case 41 is disposed between the base portion 25 of the slider 12 and the support portion 42C. The first bracket 42 is formed by bending a metal plate. The first connecting portion 42A extends forward from the front of the gear case 41, and the second connecting portion 42B extends rearward from the rear of the gear case 41. The first connecting portion 42A and the second connecting portion 42B may be fastened to the base portion 25 by fastening members such as screws or rivets. The distance between the fastening points of the first connecting portion 42A and the second connecting portion 42B is set to be longer than the front-to-rear length of the gear case 41.

[0083] A second bracket 51 is provided behind the first bracket 42 to support the electric motor 36 on the base portion 25 of the slider 12. The second bracket 51 has a connecting portion 51A that is connected to the base portion 25 and a support portion 51B that extends downward from the connecting portion 51A to the side opposite the base portion 25. The support portion 51B is perpendicular to the connecting portion 51A, and the second bracket 51 is formed in an L shape. The electric motor 36 is connected to the support portion 51B at one end thereof. In this embodiment, the electric motor 36 is disposed below the connecting portion 51A, and the second bracket 51 cantilevers the end of the electric motor 36 that is closest to the screw members 38 and 39.

[0084] The rear end of the drive shaft 43 protrudes rearward from the rear support member 41C of the gear case 41 and extends rearward through a through-hole formed in the first bracket 42. The rotating shaft 36A of the electric motor 36 is connected to the rear end of the drive shaft 43. The rotating shaft 36A and the drive shaft 43 may be connected by a coupling. The rotating shaft 36A and the drive shaft 43 may also have mating portions that mesh with each other. The rotating shaft 36A of the electric motor 36 and the drive shaft 43 are arranged on the same straight line. The electric motor 36 is formed in a cylindrical shape and extends forward and backward.

[0085] A reducer 40 may be provided between the rotary shaft 36A of the electric motor 36 and the drive shaft 43. The reducer 40 may be, for example, a planetary gear mechanism. The reducer 40 may be provided on the surface of the support portion 51B of the second bracket 51 that faces away from the electric motor 36. In other embodiments, the reducer 40 may be supported on the rear end surface of the gear case 41. The reducer 40 is an optional component and can be omitted.

[0086] The screw assembly 35, the electric motor 36, the first bracket 42, and the second bracket 51 are disposed below the base portion 25 and between the left and right slider inner walls 26. The left and right slider inner walls 26 have slider openings 55 at positions corresponding to the screw assemblies 35. The slider openings 55 are formed in the recesses 33 of the slider inner walls 26. A left portion of the threads 38A of the first screw member 38 passes through the left case opening 48 of the gear case 41 and the slider opening 55 of the left slider inner wall 26, and protrudes to the left of the left slider inner wall 26. Similarly, a right portion of the threads 39A of the second screw member 39 passes through the right case opening 48 of the gear case 41 and the slider opening 55 of the right slider inner wall 26, and protrudes to the right of the right slider inner wall 26.

[0087] As shown in Figures 2 and 10, the rail 11 is formed with thread engagement portions 57, 58 that extend in the front-rear direction and engage with the screw members 38, 39. Figure 10 shows only the rail inner side wall 17 of the rail 11. The thread engagement portions 57, 58 include a first thread engagement portion 57 formed in the left rail inner side wall 17 that engages with the thread 38A of the first screw member 38, and a second thread engagement portion 58 formed in the right rail inner side wall 17 that engages with the thread 39A of the second screw member 39. The first thread engagement portion 57 and the second thread engagement portion 58 are formed in the corresponding protrusions 22 of the rail inner side walls 17. The first thread engagement portion 57 and the second thread engagement portion 58 include a plurality of engagement holes 59 formed in the protrusions 22 aligned in the front-rear direction. The first screw member 38 moves forward and backward relative to the first screw engagement portion 57 by engaging with the multiple engagement holes 59 of the first screw engagement portion 57 at the left portion of the thread 38A of the first screw member 38 and rotating around the front-to-back direction. Similarly, the second screw member 39 moves forward and backward relative to the second screw engagement portion 58 by engaging with the multiple engagement holes 59 of the second screw engagement portion 58 at the right portion of the thread 39A of the second screw member 39 and rotating around the front-to-back direction.

[0088] The rotation of the electric motor 36 is transmitted to the first screw member 38 and the second screw member 39 via the rotation shaft 36A, the drive shaft 43, the drive gear 43A, and the first gear 38B or the second gear 39B. As a result, the first screw member 38 and the second screw member 39 rotate in the same direction. When the first screw member 38 and the second screw member 39 rotate, the first screw member 38 and the second screw member 39 move back and forth relative to the first screw engagement portion 57 and the second screw engagement portion 58, and the slider 12 moves back and forth relative to the rail 11.

[0089] As shown in FIGS. 3 and 9 , the electric slide rail 1 includes a power supply device 61 for supplying power to the electric motor 36. The power supply device 61 includes a conductive strip 62 extending longitudinally inside the rail 11 and connected to a power source 68, an electrical insulating plate 63 provided between the rail 11 and the conductive strip 62, and a conductive contact terminal 64 provided on the electric motor 36 and in sliding contact with the conductive strip 62. In this embodiment, the electrical insulating plate 63 is provided on the upper surface of the rail bottom wall 14, and the conductive strip 62 is provided on the upper surface of the electrical insulating plate 63. The conductive strips 62 are belt-shaped metal plates, and a pair of left and right conductive strips 62 extend longitudinally. The left and right conductive strips 62 are arranged along the left and right side edges of the electrical insulating plate 63 extending longitudinally.

[0090] The electrical insulating plate 63 has extensions 63A on its left and right side edges that are bent inward and above the corresponding conductive strips 62 on the left and right. Each extension 63A faces the corresponding conductive strip 62 on the left and right with a gap between them. That is, each extension 63A extends above the corresponding conductive strip 62 on the left and right. The extensions 63A prevent foreign matter from coming into contact with the conductive strips 62. The left and right side edges of the electrical insulating plate 63 may each have inclined portions 63B that are inclined upward and outward on the left and right. The left and right conductive strips 62 may be provided on the upper surfaces of the inclined portions 63B. In this case, foreign matter is even less likely to come into contact with the conductive strips 62.

[0091] The contact terminals 64 extend from the electric motor 36 between the extension portion 63A and the conductive strip 62. The contact terminals 64 are biased toward the conductive strip 62 by their own elastic force. The contact terminals 64 may be, for example, conductive metal pieces. In this embodiment, the electric motor 36 has a left contact terminal 64 that slides against the left conductive strip 62 and a right contact terminal 64 that slides against the right conductive strip 62. The electric motor 36 receives power from a power source 68 via the left and right conductive strips 62 and the left and right contact terminals 64. When the slider 12 moves back and forth relative to the rail 11, the left and right contact terminals 64 slide back and forth relative to the corresponding conductive strips 62, and the left and right contact terminals 64 remain in contact with the corresponding conductive strips 62.

[0092] The power supply device 61 is connected to a power source 68 via a control device 66. The control device 66 is provided, for example, on the floor 3. The control device 66 is an electronic control device connected to the power source 68, the left and right conductive strips 62 of each electric slide rail 1, and an operation switch 67. The operation switch 67 has a button corresponding to forward movement and a button corresponding to reverse movement. The control device 66 adjusts the power supplied to each conductive strip 62 based on a signal from the operation switch 67, and controls the direction and amount of rotation of the electric motor 36. This allows an operator to operate the electric slide rail 1 by operating the operation switch 67, thereby moving the vehicle seat 2 forward or backward relative to the floor 3. In another embodiment, the electric motor 36 may be controlled by a wireless signal from a wireless device, independent of the power supplied by the conductive strips 62.

[0093] Each rail 11 of the left and right electric slide rails 1 is connected to the vehicle floor 3 via a bracket or directly. Each rail 11 is preferably received in a rail groove 4 formed in the floor 3. The upper surface of the rail upper wall 16 of the rail 11 is preferably arranged flush with the upper surface of the floor 3. By placing the rail 11 in the rail groove 4, it is possible to prevent the rail 11 from protruding from the floor 3. Each slider 12 of the left and right electric slide rails 1 is connected to the seat cushion 5. The sliders 12 of the left and right electric slide rails 1 may be connected to each other by a connecting member.

[0094] In the electric slide rail 1 according to this embodiment, the electric motor 36 and the screw assembly 35 are fixed to the slider 12, which prevents the first screw member 38 and the second screw member 39 from tilting relative to the first screw engagement portion 57 and the second screw engagement portion 58. This allows the first screw member 38 to engage with the first screw engagement portion 57 at an appropriate angle, allowing the first screw member 38 to rotate smoothly. The same applies to the second screw member 39. As a result, an electric slide rail 1 capable of smooth operation can be provided. Furthermore, because the electric motor 36 is attached to the slider 12, which is received in the rail 11, the external dimensions of the electric slide rail 1 can be reduced. Furthermore, because the electric motor 36 is disposed inside the slider 12, the distance between the electric motor 36 and the screw assembly 35 can be shortened, and the drive shaft 43 connecting the electric motor 36 and the screw assembly 35 can be shortened. This prevents the drive shaft 43 from bending, allowing the screw assembly 35 to rotate smoothly.

[0095] Because the screw assembly 35 has both the first screw member 38 and the second screw member 39, the screw assembly 35 can be made smaller while engaging with both the first screw engagement portion 57 and the second screw engagement portion 58. Furthermore, because the direction of the reaction force that the first screw member 38 receives from the first screw engagement portion 57 is opposite to the direction of the reaction force that the second screw member 39 receives from the second screw engagement portion 58, the first screw member 38 and the first screw engagement portion 57 are reliably engaged, and the second screw member 39 and the second screw engagement portion 58 are reliably engaged.

[0096] The first screw member 38 and the second screw member 39, together with the gear case 41 and the first bracket 42, constitute the screw assembly 35, which can be easily assembled to the slider 12.

[0097] A power supply device 81, which is a variation of the power supply device 61, will be described below. The power supply device 81 enables the wire harness to be fed according to the position of the slider 12 while suppressing unnecessary movement of the wire harness relative to the floor 3 in the vehicle seat 2. In one embodiment, the wire harness is used for power supply and communication. The power supply device 81 also functions as a cover that covers an opening in the rail 11. As shown in FIGS. 11 to 13 , the power supply device 81 includes a power line 82 connected to a power source 68 via the control device 66, a cover piece 83 attached to the power line 82, and a storage case 84 that stores the power line 82 and the cover piece 83. The power line 82 is a wire harness whose outer periphery is covered with an electrical insulating material. The storage case 84 includes a storage chamber 86 defined therein, an inlet hole 87 that connects the storage chamber 86 to the outside, and a fixing part 88 that is disposed in the storage chamber 86 and fixes one end of the power line 82.

[0098] As shown in FIG. 11 , the storage case 84 is formed in a flat box shape. The inlet hole 87 of the storage case 84 is provided on a side of the storage case 84 and is connected to the front or rear end of the rail 11. In this embodiment, the inlet hole 87 is connected to the rear end of the rail 11. The inlet hole 87 is provided on the rear of the left or right side edge of the storage case 84 and opens forward. As shown in FIG. 12 , in this embodiment, the fixing portion 88 is a through-hole provided on the bottom of the storage case 84. No cover piece 83 is attached to one end of the power line 82, and the power line 82 is fixed by being inserted into the fixing portion 88. The power line 82 passes through the fixing portion 88, extends outside the storage case 84, and is connected to the control device 66.

[0099] The power line 82 passes from the fixing portion 88 through the storage chamber 86, the inlet hole 87, and the rail 11 in this order to be connected to the electric motor 36. An electric connector connected to the electric motor 36 may be provided inside the slider 12, and the power line 82 may be connected to the electric connector. A plurality of cover pieces 83 are coupled to the outer periphery of the power line 82. As shown in FIG. 13 , each cover piece 83 has an upper plate 91 and a pair of support pieces 92 protruding downward from the upper plate 91. The cover piece 83 may be formed, for example, from resin. The pair of support pieces 92 hold the power line 82 therebetween. The lower ends of each support piece 92 may be provided with first locking claws 93 that protrude toward each other. The pair of first locking claws 93 lock the power line 82, thereby maintaining the power line 82 between the pair of support pieces 92.

[0100] When the cover piece 83 is positioned within the rail 11, the left and right side edges of the upper plate 91 rest on the upper surfaces of the left and right rail upper walls 16, and the pair of support pieces 92 is disposed between the left and right rail inner walls 17. Second locking claws 94 that protrude away from each other are provided at the lower ends of the support pieces 92. The pair of second locking claws 94 abut against the corresponding rail inner walls 17, thereby determining the vertical position of the cover piece 83 with respect to the rail 11. In this embodiment, the pair of second locking claws 94 abut against lower parts of the protrusions 22 of the rail inner walls 17. In other embodiments, the pair of second locking claws 94 may abut against the lower edges of the rail inner walls 17.

[0101] The top plates 91 of adjacent cover pieces 83 have portions that overlap each other in the vertical direction. The top plates 91 of adjacent cover pieces 83 are connected to be rotatable within a predetermined range around a pivot 96 that extends vertically. The cover pieces 83, whose rotation range is restricted, are attached to the power lines 82, thereby restricting the flexing of the power lines 82 within a predetermined range. One of the multiple cover pieces 83, located closest to the electric motor 36, is connected to the rear end of the slider 12. The multiple cover pieces 83 cover the rail opening 19 on the rail 11 rearward of the slider 12. The multiple cover pieces 83 also conceal the power lines 82.

[0102] 12 , a guide wall 97 that guides the movement direction of the cover piece 83 is provided inside the storage case 84. In this embodiment, the guide wall 97 is curved in a semicircular shape in a plan view. The guide wall 97 slides against the side of the cover piece 83, smoothly curving the cover piece 83 as it moves rearward inside the storage chamber 86 and guiding it to the front of the storage chamber 86.

[0103] The upper edge of the entrance hole 87 of the storage case 84 is located above the upper surface of the rail 11. In addition, a guide slope (not shown) is provided on the side of the entrance hole 87 to guide the upper plate 91 of the cover piece 83 inside the entrance hole 87 onto the upper surface of the rail 11.

[0104] 12(A), when the slider 12 moves forward relative to the rail 11, the power line 82 and the cover piece 83 are pulled forward through the inlet hole 87. At this time, the cover piece 83 is guided by the guide slope, and the upper plate 91 is positioned above the pair of rail upper walls 16, and the pair of second locking claws 94 is positioned below the lower parts of the pair of protrusions 22. This determines the vertical position of the cover piece 83 relative to the rail 11. In this state, each cover piece 83 can slide back and forth relative to the rail 11.

[0105] 12(B), when the slider 12 moves rearward relative to the rail 11, the cover pieces 83 are pushed rearward by the slider 12 and passed through the entrance holes 87 and pushed into the storage case 84. Each cover piece 83 pushed into the storage case 84 is guided by the guide wall 97 and led to the front of the storage chamber 86.

[0106] Although the description of the specific embodiment has been completed above, the present invention is not limited to the above embodiment and can be widely modified and implemented. For example, the electric slide rail 1 may be disposed on the object so that the rail 11 extends in the left-right or up-down direction. The shapes of the rail 11 and the slider 12 can be modified as appropriate depending on the purpose. In the above embodiment, an example in which the present invention is applied to a vehicle seat has been described, but the vehicle seat according to the present invention can also be applied to various seats for aircraft, trains, etc.

[0107] Further, a pair of drive gears 43A may be provided in front and behind, and a pair of first gears 38B and second gears 39B may be provided in front and behind corresponding to the drive gears 43A.

[0108] The contact terminal 64 may be connected to other electrical devices provided in the vehicle seat 2 in addition to the electric motor 36 to supply power to the electrical devices.

[0109] Furthermore, a plurality of sliders 12 may be arranged on one rail 11. That is, a seat including a plurality of independent seat cushions 5 may be arranged on one rail 11. In this case, a conductive strip 62 may be provided corresponding to each seat.

[0110] As shown in FIG. 14 , the slider 12 may have a connecting portion 29 protruding upward from the base portion 25. The connecting portion 29 is formed in a plate shape, with its surfaces facing left and right. The slider 12 may be coupled to the seat cushion 5 at the connecting portion 29. The slider 12 is composed of a first piece 12A that constitutes the connecting portion 29, the base portion 25, the left slider inner wall 26, the left slider lower wall 27, and the left slider outer wall 28, and a second piece 12B that constitutes the connecting portion 29, the right slider inner wall 26, the right slider lower wall 27, and the right slider outer wall 28. The slider 12 may be formed by overlapping and fastening the first piece 12A and the second piece 12B to each other at their respective connecting portions 29. [Explanation of symbols]

[0111] 1: Electric slide rail 2: Vehicle seats 3: Floor 5: Seat cushion 11: Rail 12: Slider 17: Rail inner wall 22: Protrusion 25: Base part 26: Inner wall of slider 35: Screw assembly 36: Electric motor 36A: Rotating shaft 38: First screw member 38A: Thread 38B: 1st gear 39: Second screw member 39A: Thread 39B: 2nd gear 41: Gear case 42: First bracket 42A: 1st joint 42B: 2nd joint 42C: Support part 43: Drive shaft 43A: Drive gear 45: 1st bearing part 46:Second bearing part 47:Third bearing part 51: Second bracket 51A:Joining part 51B: Support part 57: First screw engagement part 58: Second screw engagement part 59: Engagement hole 61: Power supply device 62: Conductive strip 63: Electrical insulating board 63A: Extension part 64: Contact terminal

Claims

1. An electric slide rail, a rail having a groove-shaped cross section and extending in the front-rear direction; a slider received in and slidably engaged with the rail; a screw assembly including a screw member supported on the slider so as to be rotatable around the front-rear direction; an electric motor supported by the slider and configured to rotate the screw member; a thread engagement portion extending in the front-rear direction and formed on the rail so as to engage with the screw member; The rail has a rail upper wall whose surface faces up and down, and a rail inner wall whose surface faces left and right and extends downward from an end of the rail upper wall, the threaded engagement portion is formed on the rail inner wall at a position spaced downward from an end of the rail upper wall, The slider has a plate-shaped base portion with its surfaces facing up and down, the screw member is disposed below the base portion, the slider has an inner slider wall extending downward from a side edge of the base portion; a recess formed in the slider inner wall, the recess recessed toward the screw member; A slider opening is formed in the recess, The screw member passes through the slider opening and protrudes to the screw engagement portion.

2. The rail inner wall is formed with a protrusion that protrudes toward the slider and extends in the front-rear direction, The electric slide rail according to claim 1 , wherein the screw engagement portion is formed on the protrusion.

3. The electric slide rail according to claim 2 , wherein the recess is disposed at a position opposite the protrusion in the left-right direction.

4. The electric slide rail according to claim 1 , wherein a rotation axis of the screw member is located below the base portion.

5. The electric slide rail according to claim 1 , wherein an upper end of the screw member is located below the base portion.

6. The electric slide rail according to claim 1 , wherein the screw member is supported below the base portion.

7. The recess and the screw member extend in the front-rear direction, The electric slide rail according to claim 1 , wherein a length of the recess in the front-rear direction is longer than a length of the screw member in the front-rear direction.

8. The electric slide rail according to claim 1 , wherein the screw member and the electric motor are disposed below the base portion, to the sides of the recess, and aligned in the front-rear direction.

9. the screw member and the electric motor extend in the front-rear direction and are aligned in the front-rear direction below the base portion, The electric slide rail according to claim 1 , wherein a length of the recess in the front-rear direction is longer than a sum of a length of the screw member in the front-rear direction and a length of the electric motor in the front-rear direction.

Images