Push nut and vehicle seat using the same

Abstract

To provide a push nut which can be easily removed.SOLUTION: The push nut 60 capable of engaging with the shaft member 37 includes the annular portion 61 into which the shaft member 37 is inserted, and the plurality of claws 62 extending from the inner peripheral edge of the annular portion 61 toward the axial line of the annular portion 61 and having the beams 63 capable of engaging with the shaft member 37 at the 63a of the tip edge thereof, and at least one of the plurality of claws 62 further has the tab 64 protruding laterally from the beams 63.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a push nut and a vehicle seat using the same. [Background technology]

[0002] Conventionally, push nuts are used to secure components attached to shaft members and prevent them from falling off. For example, Patent Document 1 discloses a push nut with multiple pawls formed at equal intervals in the circumferential direction from the inner periphery. When a shaft member is inserted into the push nut, the pawls elastically deform so that they protrude in a direction away from the axis of the shaft member. This engages the shaft member and the push nut. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2016-013726 Summary of the Invention [Problem to be solved by the invention]

[0004] After attaching a push nut to a shaft member, it may need to be removed from the shaft member. In such cases, a worker inserts a tool such as a pick tool or thin pliers between the pawl of the push nut and the shaft member and repeatedly bends the tip of the pawl away from the shaft member to release the engagement between the push nut and the shaft member. However, repeatedly inserting a tool into the small gap between the pawl and the shaft member to bend multiple pawls while the push nut is engaged takes time.

[0005] In view of the above background, an object of the present invention is to provide a push nut that is easy to remove. [Means for solving the problem]

[0006] In order to solve the above problem, one aspect of the present invention is a push nut (60) that can be engaged with an axial member (37), comprising an annular portion (61) into which the axial member is inserted, and a plurality of claws (62) that extend from the inner peripheral edge of the annular portion toward the axis of the annular portion and have a beam portion (63) at their tip edge (63a) that can be engaged with the axial member, and at least one of the plurality of claws further has a tab (64) protruding laterally from the beam portion.

[0007] According to this aspect, when removing the push nut from the shaft member, the worker can grip the tab with a tool to bend the pawl without inserting a tool into the gap between the pawl and the shaft member, making it easy to remove the push nut from the shaft member.

[0008] In the above aspect, the plurality of claws may be formed in a rotational symmetry shape centered on the axis.

[0009] According to this aspect, it is possible to prevent the tabs from interfering with each other.

[0010] In the above aspect, the tab may be provided at the tip end (63A) of the beam portion.

[0011] According to this aspect, the distance between the tip portion, which is the point of application of force, and the base portion of the beam portion, which is the fulcrum, can be increased, so that the worker can bend the nail with less force.

[0012] In the above aspect, the tab, the base portion (63B) of the beam portion, and the annular portion may form a recess (65) recessed in the circumferential direction around the axis.

[0013] According to this embodiment, the circumferential width of the base of the beam is reduced, so that the rigidity of the base is lower than that of the tip, allowing the worker to easily bend the base 63B of the beam.

[0014] In the above aspect, the beam portions may be arranged on an imaginary conical surface centered on the axis, and the tabs may protrude outward from the imaginary conical surface.

[0015] According to this aspect, since the tab protrudes outward from the imaginary conical surface, it is easy for an operator to grasp the tab with a tool.

[0016] In the above aspect, the tip edges of the plurality of beam portions may be recessed in an arc shape.

[0017] According to this aspect, when the push nut is attached to the shaft member, the tip edge of the beam portion engages with the shaft member over a wide area, thereby enabling the push nut and the shaft member to be firmly engaged with each other.

[0018] In the above aspect, the length of each of the beam portions in the extension direction may be longer than the width of the annular portion in the radial direction.

[0019] According to this aspect, the beam portion and the tab can have a predetermined length, so that the worker can easily bend the claw.

[0020] In order to solve the above-mentioned problems, one aspect of the present invention is a vehicle seat (1) having the push nut, comprising: a seat cushion frame (13A); a seat back frame (13B); left and right reclining devices (36) fixed to the seat cushion frame and the seat back frame and supporting the angle of the seat back frame relative to the seat cushion frame so as to be changeable; an electric actuator (35) provided on the seat back frame; and a transmission shaft (37) as the axial member extending left and right, passing through an output portion (45) of the electric actuator and input portions (55) of the left and right reclining devices, and non-rotatably engaging with the output portion and the left and right input portions, to transmit the driving force of the electric actuator to the left and right input portions, the left and right ends of the transmission shaft protruding outward to the left and right from the left and right reclining devices, the push nuts being attached to the left and right ends of the transmission shaft, respectively, and the left and right push nuts abutting against the left and right reclining devices, thereby restricting axial movement of the transmission shaft.

[0021] According to this aspect, it is possible to provide a vehicle seat that is easy to disassemble. Specifically, a worker can grasp the tab with a tool and remove the push nut, thereby removing the transmission shaft from the seat cushion, the seat back, and the reclining device.

[0022] In the above aspect, the tab may be spaced apart from the transmission shaft.

[0023] According to this aspect, since the tab is separated from the transmission shaft, it is easy for an operator to grasp the tab with a tool.

[0024] In the above aspect, the tab may protrude in a direction away from the transmission shaft.

[0025] According to this aspect, since the tab protrudes in a direction away from the transmission shaft, it is easier for an operator to grasp the tab with a tool. [Effects of the Invention]

[0026] According to the above aspect, it is possible to provide a push nut that is easy to remove. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a perspective view of a seat according to an embodiment; [Figure 2] FIG. 1 is a front view of the reclining mechanism and its surroundings according to an embodiment; [Figure 3] Cross-sectional view of the periphery of the reclining device according to the embodiment. [Figure 4] 1 is a side view of the periphery of a reclining device according to an embodiment; [Figure 5] FIG. 1 is a plan view showing a push nut according to an embodiment; [Figure 6] 1A and 1B are a side view and a cross-sectional view showing a push nut according to an embodiment; [Figure 7] FIG. 1 is a perspective view showing a push nut according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0028] The push nut and the vehicle seat using the same of the present invention will be described below with reference to the drawings. In the drawings and the following description, front, rear, left, right, up and down are directions defined relative to a passenger seated in the vehicle seat.

[0029] <Sheet 1> First, a seat 1 according to this embodiment will be described with reference to Figures 1 to 4. The seat 1 is mounted in an automobile. As shown in Figure 1, the seat 1 has slide rails 3 connected to a floor 2 of the automobile and a seat body 4 supported by the slide rails 3. The slide rails 3 have left and right rails 6 (lower rails) connected to the floor 2, and left and right sliders 7 (upper rails) supported on the left and right rails 6 so as to be slidable, respectively. Each rail 6 extends in the front-to-rear direction.

[0030] The seat body 4 has a seat cushion 11 that supports the buttocks of the occupant from below, a seat back 12 that supports the back of the occupant from behind, and a headrest provided on the upper part of the seat back 12.

[0031] The seat body 4 also has a seat frame 13, a pad supported by the seat frame 13, and a covering material covering the surface of the pad. The seat frame 13 includes a seat cushion frame 13A that constitutes the seat cushion 11, and a seat back frame 13B that constitutes the seat back 12.

[0032] The seat cushion frame 13A has left and right seat cushion side members 21 extending in the front-rear direction, a front member 22 extending in the left and right direction and connected to the front ends of the left and right seat cushion side members 21, and a rear member 23 extending in the left and right direction and connected to the rear ends of the left and right seat cushion side members 21. The front member 22 may be a pan frame formed in a flat plate shape. The left and right seat cushion side members 21 are connected to the corresponding sliders 7 on the left and right.

[0033] The seatback frame 13B has left and right seatback side members 26 that extend vertically, an upper member 27 that extends horizontally and is joined to the upper ends of the left and right seatback side members 26, a lower member 28 that extends horizontally and is joined to the lower ends of the left and right seatback side members 26, and an intermediate member 29 that extends horizontally below the upper member 27 and is joined to intermediate portions of the left and right seatback side members 26. The upper member 27 is provided with a pair of headrest guides 30 for supporting headrest pillars (not shown).

[0034] <Reclining mechanism R> As shown in FIG. 2, the lower ends of the left and right seatback side members 26 are supported by the rear ends of the corresponding left and right seat cushion side members 21 via a reclining mechanism R. The reclining mechanism R has a known structure. The reclining mechanism R includes an electric actuator 35 provided on the seatback frame 13B, a pair of reclining devices 36 fixed to the seat cushion frame 13A and the seatback frame 13B, and a transmission shaft 37 that transmits the driving force of the electric actuator 35 to the left and right reclining devices 36. Also, as shown in FIG. 3, a first through hole 26a is provided at the lower end of each seatback side member 26. Also, a second through hole 21a is provided at the rear end of each seat cushion side member 21 at a position aligned with the corresponding first through hole 26a. The transmission shaft 37 is an example of a shaft member.

[0035] <Electric Actuator 35> As shown in FIG. 2, the electric actuator 35 has an electric motor 40 that generates power in response to the supply of electric power, and a reduction gear 41 that reduces the speed of the rotational output from the electric motor 40 and applies a driving force to the transmission shaft 37.

[0036] The reduction gear 41 includes, for example, a worm provided on the output shaft of the electric motor 40, a wheel that meshes with the worm, an output portion 45 that meshes with the wheel, and a case 46 that rotatably houses the worm, the wheel, and the output portion 45. The output portion 45 may be formed by a spur gear. In another example, the output portion 45 may be formed by the wheel, or the wheel and the output portion 45 may be connected via a gear mechanism or the like.

[0037] The output part 45 is provided with an insertion hole 45a into which the transmission shaft 37 is inserted. The insertion hole 45a passes through the output part 45 along the rotation axis of the output part 45. The transmission shaft 37 is fitted into the insertion hole 45a so as not to rotate. For example, splines that fit into each other may be formed on the inner circumferential surface of the insertion hole 45a and the outer circumferential surface of the transmission shaft 37.

[0038] The case 46 is fixed to the seatback frame 13B by fasteners such as bolts (not shown). In this embodiment, as shown in Figures 1 and 2, the electric actuator 35 is provided on the inner surface of one of the seatback side members 26. In other embodiments, the electric actuator 35 may be provided on the outer surface of the seatback side member 26.

[0039] <Reclining device 36> The reclining device 36 supports the seatback frame 13B relative to the seat cushion frame 13A. The reclining device 36 is configured to be able to change the angle of the seatback frame 13B relative to the seat cushion frame 13A (hereinafter referred to as the tilt angle). The reclining device 36 may be, for example, a Taumel-type reclining mechanism R. The reclining device 36 will be described with reference to FIGS. 3 and 4. The reclining device 36 includes an external gear 50 fixed to the seatback frame 13B, an internal gear 51 fixed to the seat cushion frame 13A, a retaining member 52 fitted to the outer circumferential surface of the internal gear 51 and sandwiching the external gear 50 together with the internal gear 51, and a plate 53 for transmitting the biasing force of a push nut 60 (described later) to the internal gear 51. The internal gear 51 has internal teeth formed on its inner wall that mesh with the external teeth of the external gear 50. 3 and 4, the seatback frame 13B and the external gear 50, and the seat cushion frame 13A and the internal gear 51 are each fixed by welding. The external gear 50, the internal gear 51, the holding member 52, and the plate 53 all have a substantially circular disk-like outer shape. The holding member 52 and the plate 53 are each formed with a first opening 52a and a second opening 53a through which the transmission shaft 37 passes in the thickness direction.

[0040] A cylindrical portion 50a extending toward the internal gear 51 is formed at the center of the external gear 50. An insertion hole 51a is formed at the center of the internal gear 51. The cylindrical portion 50a of the external gear 50 is inserted into the insertion hole 51a of the internal gear 51.

[0041] A cam member 55 is disposed within the cylindrical hole 50b of the cylindrical portion 50a of the external gear 50. The cam member 55 includes a cylindrical portion 55a and a flange portion 55b extending radially outward from the cylindrical portion 55a. The flange portion 55b further includes an extending portion 55c, the peripheral edge of which extends in the direction of extension of the cylindrical portion 55a. A coupling hole 55d into which the transmission shaft 37 is inserted is formed in the cylindrical portion 55a of the cam member 55. The cam member 55 and the transmission shaft 37 are non-rotatably engaged with each other. That is, the driving force of the electric actuator 35 is input to the cam member 55 via the transmission shaft 37. For example, splines that fit with each other may be formed on the inner circumferential surface of the coupling hole 55d of the cam member 55 and the outer circumferential surface of the transmission shaft 37. The cam member 55 is an example of an input portion.

[0042] The cam member 55 is configured so that the position of the external gear 50 relative to the internal gear 51 can be changed via a cam mechanism (not shown) by inputting a driving force from the electric actuator 35. Specifically, in normal operation, the external gear 50 and the internal gear 51 of the reclining device 36 are meshed with each other, thereby prohibiting relative movement between the internal gear 51 and the cam member 55. Therefore, the tilt angle is fixed. In other words, the reclining device 36 is in a locked state.

[0043] On the other hand, when the driving force of the electric actuator 35 is input to the cam member 55 via the transmission shaft 37, the extension 55c of the cam member 55 transmits the power to the external gear 50 via the cam mechanism, changing the position of the external gear 50 relative to the internal gear 51. This causes the meshing position between the internal gear 51 and the external gear 50 to move, causing relative movement between the internal gear 51 and the cam member 55, changing the tilt angle. In other words, the reclining device 36 enters an unlocked state.

[0044] <Transmission shaft 37> The transmission shaft 37 extends left and right and passes through the output portion 45 of the electric actuator 35 and the cam members 55 of the left and right reclining devices 36. As shown in FIG. 3, the transmission shaft 37 is a splined shaft with multiple grooves on its outer periphery, and is non-rotatably engaged with the output portion 45 of the electric actuator 35 and the cam members 55 of the left and right reclining devices 36.

[0045] The left and right ends of the transmission shaft 37 protrude outward to the left and right from the left and right reclining devices 36, and a push nut 60 is attached to each of the left and right ends of the transmission shaft 37. The left and right push nuts 60 are positioned so as to abut against the plates 53 of the left and right reclining devices 36. In addition, near the left and right ends of the transmission shaft 37, circumferential engagement grooves 37a are formed for the push nuts 60 to engage with.

[0046] <Push nut 60> Next, a push nut 60 according to this embodiment will be described with reference to Figures 5 to 7. The push nut 60 is configured to be able to engage with the transmission shaft 37, which is an axial member. Specifically, the push nut 60 includes an annular portion 61 into which the transmission shaft 37 is inserted, and a plurality of pawls 62 extending from the inner peripheral edge of the annular portion 61 toward the axis of the annular portion 61. The push nut 60 is made of metal, for example, an iron material.

[0047] The inner diameter of the annular portion 61 is larger than the diameter of the transmission shaft 37 (see FIG. 4). The multiple claws 62 are formed in a rotationally symmetrical shape centered on the axis of the annular portion 61. In this embodiment, three claws 62 are formed, but this is not limited to this, and the number of claws 62 is not particularly limited. Each claw 62 has a beam portion 63 that can engage with the transmission shaft 37 at its tip edge 63a, and a tab 64 that protrudes laterally from the beam portion 63.

[0048] The beam portion 63 has a generally rectangular shape in a plan view, and the length of the beam portion 63 in the extension direction is longer than the width of the annular portion 61 in the radial direction. Furthermore, the tip edge 63a of the beam portion 63 is recessed in an arc shape centered on the axis of the annular portion 61. As a result, when the push nut 60 is attached to the transmission shaft 37, the tip edge 63a of the beam portion 63 and the transmission shaft 37 engage over a wide range. This allows the push nut 60 and the transmission shaft 37 to engage firmly.

[0049] The tab 64 is provided on the tip end 63A of the beam portion 63. Specifically, the tab 64 is integrally provided on the beam portion 63 so as to extend rightward from the tip edge 63a of the beam portion 63. Therefore, in the circumferential direction of the annular portion 61, the length including the tip end 63A and the tab 64 is longer than the length of the base portion 63B. In other words, the push nut 60 has a gap between the pair of claws 62, and the length of this gap in the circumferential direction of the annular portion 61 is longest between the base portions 63B. Meanwhile, the circumferential length between the tip end 63A and the tab 64 is shorter than the length between the base portions 63B. Furthermore, the beam portion 63 may be generally trapezoidal in plan view, with the side edge where the tab 64 is not formed expanding in the circumferential direction of the annular portion 61 toward the base portion 63B of the beam portion 63. In this case, the gap between the pair of claws 62 may be formed such that the length between the base portions 63B in the circumferential direction of the annular portion 61 is shorter than the length between the tip portion 63A and the tab 64.

[0050] In this embodiment, the tab 64 has a tapered shape that narrows in the protruding direction in a plan view, but is not limited to this and may have a substantially rectangular shape. The tab 64 may also be provided between the tip 63A and the base 63B of the beam 63. Furthermore, the tab 64 may be provided so as to protrude from the left side of the beam 63, and each claw 62 may have a tab 64 that protrudes to a different side.

[0051] 5, the tab 64, the base 63B of the beam 63, and the annular portion 61 form a recess 65 that is recessed in the circumferential direction around the axis. In this embodiment, the tip 63A and base 63B of the beam 63 have approximately the same width in the circumferential direction of the annular portion 61. In other embodiments, the base 63B of the beam 63 may be formed shorter than the tip 63A in the circumferential direction of the annular portion 61. In this case, the recess 65 is formed so as to cut out the beam 63.

[0052] As shown in Figure 6, each beam portion 63 is arranged on an imaginary conical surface centered on the axis of the annular portion 61. The tip edges 63a of the multiple beam portions 63 are arranged on approximately the same circumference on the side surface. The diameter of the circle is formed to be smaller than the diameter of the transmission shaft 37. As a result, when the transmission shaft 37 is inserted, each claw is elastically deformed so as to protrude in a direction away from the axis of the transmission shaft 37. Therefore, the tip edges 63a of the multiple beam portions 63 engage with the transmission shaft 37 due to a restoring force.

[0053] 7, the tabs 64 protrude outward from the imaginary conical surface. That is, when the transmission shaft 37 is inserted, the tabs 64 are arranged so as to be spaced apart from the transmission shaft 37.

[0054] The push nut 60 is manufactured, for example, by performing a press process (punching and forming, etc.) on a plate-shaped metal material. In this case, it is preferable that each tab 64 is bent in a direction away from the transmission shaft 37 when the transmission shaft 37 is inserted. This allows the tab 64 to protrude in a direction away from the transmission shaft 37 when the transmission shaft 37 is inserted. Furthermore, it is preferable that the length of the tab 64 in the protruding direction during the press process is long enough so that it does not come into contact with other adjacent claws 62. This allows the push nut 60 to be manufactured from a single metal plate.

[0055] <How to assemble the seat frame 13> The following describes a method for assembling the seat frame 13 using the push nuts 60. First, the worker places the reclining device 36 between the lower end of each of the left and right seatback side members 26 and the rear end of the corresponding seat cushion side member 21. Then, the worker fixes the seatback frame 13B and the external gear 50, and the seat cushion frame 13A and the internal gear 51 by welding (see FIG. 3).

[0056] Next, the worker temporarily fastens the electric actuator 35 to the seatback frame 13B using fasteners such as bolts. After that, the worker inserts the transmission shaft 37 so that it passes through one of the seat cushion side members 21, the reclining device 36, and the seatback side member 26. Specifically, the transmission shaft 37 is inserted into the second through-hole 21a of the seat cushion side member 21, the connecting hole 55d of the cam member 55, and the first through-hole 26a of the seatback side member 26.

[0057] Next, the worker inserts the transmission shaft 37 into the electric actuator 35. Specifically, the transmission shaft 37 is inserted into the insertion hole 45a of the output portion 45 of the electric actuator 35.

[0058] Next, the worker inserts the transmission shaft 37 so that it penetrates the other seatback side member 26, the reclining device 36, and the seat cushion side member 21. In this case, as shown in FIG. 3, the transmission shaft 37 protrudes outward to the left and right from the left and right reclining devices 36. This connects the seat cushion frame 13A, the seatback frame 13B, and the pair of reclining devices 36 via the transmission shaft 37.

[0059] Next, the worker inserts the push nuts 60 into the left and right ends of the transmission shaft 37. Specifically, the worker inserts the push nuts 60 into the transmission shaft 37 while elastically deforming the claws 62 of the push nuts 60 so that they protrude outward to the left and right and away from the axis of the transmission shaft 37. As a result, the claws 62 engage with the transmission shaft 37 due to their restoring force. In this case, the push nuts 60 are inserted to a position where they come into close contact with the outer surfaces of the left and right reclining devices 36, i.e., the plates 53. This restricts axial movement of the transmission shafts 37 of the reclining devices 36, i.e., outward to the left and right. Furthermore, at this position, the tip edges 63a of the beam portions 63 of the push nuts 60 engage with the engagement grooves 37a of the transmission shaft 37. This prevents the push nuts 60 from falling off the transmission shaft 37. In this case, the tip edge 63a of the beam portion 63 fits into the engagement groove 37a of the transmission shaft 37, so the worker can get a sense of fitting the push nut 60, and the push nut 60 can be positioned easily.

[0060] Next, the worker finally tightens the electric actuator 35, which has been loosely fastened to the seat back frame 13B, to the seat back frame 13B. This completes the assembly of the seat frame 13.

[0061] <How to remove the push nut 60> Next, a method for removing the push nut 60 engaged with the transmission shaft 37 will be described. First, the worker pinches the tab 64 of the push nut 60 with a tool capable of gripping an object, such as pliers, and then bends the claws 62 in a direction away from the transmission shaft 37. By performing this operation on each of the claws 62, the engagement between the transmission shaft 37 and the push nut 60 is released. Then, the worker removes the push nut 60 from the transmission shaft 37.

[0062] <Effects> At least one of the multiple claws 62 of the push nut 60 further has a tab 64 protruding laterally from the beam portion 63. As a result, when removing the push nut 60 from the transmission shaft 37, a worker can grip the tab 64 with a tool to bend the claw 62. This allows the worker to easily remove the push nut 60 from the transmission shaft 37 without inserting a tool into the gap between the claw 62 and the transmission shaft 37. Furthermore, by using the push nut 60 in a vehicle seat, a vehicle seat that can be easily dismantled can be provided. Specifically, a worker can remove the push nut 60 by gripping the tab 64 with a tool and removing the push nut 60, thereby extracting the transmission shaft 37 from the seat cushion frame 13A, the seatback frame 13B, and the reclining device 36.

[0063] The plurality of claws 62 are formed in a rotationally symmetrical shape about the axis, which prevents the tabs 64 from interfering with each other.

[0064] The tab 64 is provided at the tip 63A of the beam 63. This increases the distance between the tip 63A, which is the point of force, and the base 63B of the beam 63, which is the fulcrum, so that the worker can bend the claw 62 with less force.

[0065] The tab 64, the base 63B of the beam 63, and the annular portion 61 form a recess 65 that is recessed in the circumferential direction around the axis. This reduces the circumferential width of the base 63B of the beam 63, making the rigidity of the base 63B lower than the rigidity of the tip 63A. This allows the worker to easily bend the base 63B of the beam 63.

[0066] The beam portions 63 are arranged on an imaginary conical surface centered on the axis of the annular portion 61, and the tabs 64 protrude outward from the imaginary conical surface. That is, when the transmission shaft 37 is inserted, each tab 64 protrudes in a direction away from the transmission shaft 37. This makes it easy for an operator to grip the tabs 64 with a tool.

[0067] The length of each beam portion 63 in the extension direction is longer than the width in the radial direction of the annular portion 61. This allows the beam portion 63 and the tab 64 to have a predetermined length, making it easy for the worker to bend the claw 62.

[0068] Each tab 64 is bent in a direction away from the transmission shaft 37 when the transmission shaft 37 is inserted. That is, each tab 64 is spaced apart from the transmission shaft 37. This makes it easy for an operator to grasp the tab 64 with a tool.

[0069] 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 transmission shaft 37 is not limited to a spline shaft and may have a hexagonal cross section. In this case, the insertion hole 45a of the output portion 45 of the electric actuator 35 and the coupling hole 55d of the cam member 55 may have a hexagonal shape corresponding to the transmission shaft 37. Although the description has been made assuming that the reclining device 36 employs a Taumel-type reclining mechanism R, the present invention is not limited to this. The reclining device 36 may also have a known reclining mechanism including a spiral spring.

[0070] Furthermore, the push nut 60 may be formed in a flat plate shape when not inserted into the transmission shaft 37. In this case, when the transmission shaft 37 is inserted into the annular portion 61, each beam portion 63 may be deformed to protrude in the insertion direction of the transmission shaft 37 and be arranged on an imaginary conical surface. In this embodiment, all of the claws 62 have tabs 64, but in other embodiments, at least one claw 62 may have a tab 64 and the other claws may have only beam portions 63.

[0071] In this embodiment, the seat 1 installed in an automobile has been described as an example of a vehicle seat, but the present invention is not limited to automobiles. For example, the vehicle seat may also be applied to seats installed in ground-traveling vehicles with wheels, such as trains, or in aircraft and ships that move on non-ground surfaces.

[0072] In addition, the specific configuration, arrangement, quantity, material, etc. of each member or part can be changed as appropriate within the scope of the spirit of the present invention. Furthermore, all of the components shown in the above embodiment are not essential and can be selected as appropriate. [Explanation of symbols]

[0073] 1: Sheet 13A: Seat cushion frame 13B: Seat back frame 35: Electric actuator 36: Reclining device 37: Transmission shaft (an example of a shaft member) 45: Output section 55: Cam member (an example of an input part) 60: Push nut 61: Annular section 62: Nails 63:Beam part 63A:Tip 63B: Base 63a: Tip edge 64: Tab 65: Recess

Claims

1. A push nut engageable with a shaft member, an annular portion into which the shaft member is inserted; a plurality of claws extending from an inner peripheral edge of the annular portion toward an axis of the annular portion and having beam portions at their tip edges that can engage with the shaft member; At least one of the plurality of claws further includes a tab projecting laterally from the beam portion.

2. 2. The push nut according to claim 1, wherein the plurality of pawls are formed in a rotationally symmetrical shape about the axis.

3. 2. The push nut according to claim 1, wherein the tab is provided at a tip end of the beam portion.

4. 3. The push nut according to claim 2, wherein the tab, the base of the beam, and the annular portion form a recess recessed in a circumferential direction about the axis.

5. the plurality of beam portions are arranged on an imaginary conical surface having the axis line as its center, 3. The push nut according to claim 2, wherein the plurality of tabs protrude outward from the imaginary conical surface.

6. 2. The push nut according to claim 1, wherein the tip edges of the beam portions are recessed in an arc shape.

7. 2. The push nut according to claim 1, wherein the length of each of the beam portions in the extending direction is longer than the width of the annular portion in the radial direction.

8. A vehicle seat having a push nut according to any one of claims 1 to 7, Seat cushion frame, A seat back frame, left and right reclining devices fixed to the seat cushion frame and the seat back frame, and supporting the seat back frame so as to change the angle of the seat back frame relative to the seat cushion frame; an electric actuator provided on the seat back frame; a transmission shaft as the shaft member that extends left and right, penetrates the output portion of the electric actuator and the input portions of the left and right reclining devices, and is non-rotatably engaged with the output portion and the left and right input portions, and transmits the driving force of the electric actuator to the left and right input portions; left and right ends of the transmission shaft protrude outwardly to the left and right from the left and right reclining devices, The push nuts are attached to the left and right ends of the transmission shaft, The left and right push nuts abut against the left and right reclining devices, thereby restricting axial movement of the transmission shaft.

9. 9. The vehicle seat of claim 8, wherein the tab is spaced apart relative to the transmission shaft.

10. The vehicle seat according to claim 8, wherein the tab projects in a direction away from the transmission shaft.

Images