JP7524818B2 - Reclining device - Google Patents

Description

An embodiment of the present invention relates to a reclining device.

Conventionally, for example, a seat installed in a vehicle (such as an automobile) is composed of a seat cushion, which is a seat surface, and a seat back, which is a back support surface. In the case of a seat for a vehicle, an adjustment mechanism that can adjust the posture of the seat, that is, the inclination angle of the seat back relative to the seat cushion, according to the physique and preferences of the user (e.g., passenger, etc.), the usage situation, etc., so-called a reclining device is often built in. For example, in order to realize an angle of the seat back that does not cause fatigue when driving a vehicle, it is configured to be possible to finely adjust the angle. In this case, the angle is adjusted using power from a power source such as a motor. For example, there is a system that realizes minute angle adjustments using an eccentric mechanism consisting of an internal gear and an external gear with different numbers of teeth. Specifically, an external gear with fewer teeth than the number of teeth of the internal gear is prepared, and the center of rotation of the external gear is eccentric with respect to the center of rotation of the internal gear. Then, the angle of the seat back is finely adjusted with respect to the seat cushion by rotating the external gear while gradually eccentric.

Patent No. 4189760

In the case of a reclining device using an eccentric mechanism as described above, the internal gear and the external gear are biased against the internal gear using a wedge mechanism or the like to prevent unnecessary gaps from occurring in the meshing portion, allowing for smooth eccentric rotation without rattle. However, there are cases where a large load is input to the seat back. For example, when a configuration with a biasing spring is adopted to automatically raise the reclining device forward when it is manually operated, a load may be input due to the biasing force of the biasing spring, or a load may be input due to a heavy user leaning against the seat back. In such cases, the input load may prevent the wedge mechanism from operating smoothly, and the biasing of the meshing portion between the internal gear and the external gear may be insufficient, resulting in a gap between the tooth surfaces. Furthermore, due to the gap between the tooth surfaces, even though the seat back is fixed (locked) to the seat cushion, it can easily move when pushed by hand (it rattles and swings at a small angle), which can cause a problem that the quality of the reclining device can be reduced.

Therefore, one of the objectives of the present invention is to provide a reclining device equipped with a reclining mechanism that can fully function the wedge mechanism, prevent gaps from occurring between the meshing gears, and suppress rattling of the seat back, even when a large load is input to the seat back (seat cushion frame).

A reclining device according to an embodiment of the present invention includes, for example, a seat back frame that supports a seat back, a seat cushion frame that supports a seat cushion, a drive source attached to either the seat back frame or the seat cushion frame, and a reclining mechanism that adjusts the angle of the seat back frame relative to the seat cushion frame using power from the drive source. The reclining mechanism includes a first gear having internal teeth connected to one side of the seatback frame or the seat cushion frame, a second gear having external teeth capable of meshing with the internal teeth and eccentrically rotatable relative to the first gear, a drive pin connected to the drive source and partially inserted into a first central hole formed in one of the first gear or the second gear and supported rotatably, a ring-shaped intermediate member arranged such that an inner peripheral side surrounds the drive pin and an outer peripheral side contacts a second central hole formed in the other of the first gear or the second gear, a pair of wedge members arranged between the drive pin and the intermediate member and shaped to be wedgeable in a separating direction along an inner peripheral surface of the intermediate member, and a biasing member that biases the pair of wedge members in the separating direction. According to this configuration, for example, the wedge member is disposed between the intermediate member, whose outer periphery is in contact with the second center hole of the second gear, and the drive pin, so that it does not come into direct contact with the first gear and the second gear. As a result, even if a load is input to the first gear or the second gear, it is possible to prevent the load from directly affecting the wedge member, and the wedge driving action of the wedge member is performed without being hindered by the biasing member, and a biasing force is applied to the first gear and the second gear by the wedging effect of the wedge member, suppressing the occurrence of gaps at the meshing portion, in other words, suppressing rattling of the seat back frame (seat back).

In addition, the reclining device according to the embodiment of the present invention may have, for example, a first engagement portion formed on at least a portion of the circumferential direction of the inner circumferential surface of the intermediate member, and a second engagement portion that can engage with the first engagement portion formed on at least a portion of the circumferential direction of the outer circumferential surface of the drive pin. With this configuration, for example, the intermediate member and the drive pin rotate integrally, so that eccentric rotation of the first gear and the second gear can be realized while maintaining the relative position of the wedge member disposed between the intermediate member and the drive pin.

The drive pin of the reclining device according to the embodiment of the present invention may be formed with a flange portion that protrudes radially outward, and the intermediate member and the pair of wedge members may be supported by the flange portion in a direction perpendicular to the rotation direction of the drive pin. With this configuration, for example, the intermediate member and the pair of wedge members can be easily and stably supported by the drive pin, and the operation of the reclining mechanism can be stabilized.

In addition, in the reclining device according to an embodiment of the present invention, for example, the drive pin may be supported by the first gear, the intermediate member may be supported by the second gear, and when the wedge member is biased to the wedging position, the intermediate member may bias the second gear in a first direction in the outer radial direction, and the drive pin may bias the first gear in a second direction opposite to the first direction. With this configuration, for example, it is possible to more reliably suppress the occurrence of gaps in the meshing portion of the first gear and the second gear.

FIG. 1 is an exemplary schematic side view showing a vehicle seat to which a reclining device (reclining mechanism) according to an embodiment can be applied. FIG. 2 is an exemplary schematic exploded perspective view of the reclining device according to the embodiment, viewed from the power drive mechanism side. FIG. 3 is an exemplary schematic exploded perspective view of the reclining device according to the embodiment, viewed from the side of the manual drive mechanism opposite to the view shown in FIG. 2 . FIG. 4 is an exemplary schematic side view of an assembly diagram of the reclining device according to the embodiment. FIG. 5 is an exemplary schematic assembly diagram of the reclining device according to the embodiment, as viewed from the power drive mechanism side. FIG. 6 is an exemplary schematic assembly diagram of the reclining device according to the embodiment, as viewed from the manual drive mechanism side. FIG. 7 is an exemplary schematic diagram showing an engagement state between a first gear and a second gear of the reclining device according to the embodiment, and a wedge mechanism for the first gear and the second gear. FIG. 8 is an exemplary schematic diagram showing a lock mechanism of the manual drive mechanism of the reclining device according to the embodiment. FIG. 9 is a schematic plan view illustrating an example shape of an intermediate member that constitutes the wedge mechanism of the reclining device according to the embodiment. FIG. 10 is an exemplary schematic plan view showing the shape of one second wedge member of a pair of wedges (first wedge member, second wedge member) that constitute the wedge mechanism of the reclining device according to the embodiment. FIG. 11 is an exemplary schematic plan view showing the shape of a striker pin of the reclining device according to the embodiment, and a cross-sectional view taken along the line DD of the plan view. FIG. 12 is a cross-sectional view taken along the line CC of FIG. 7, and is an exemplary schematic cross-sectional view showing a state in which, in addition to the first gear and the second gear, the intermediate member, the pair of wedges, the striker pin, and the wedge spring are assembled. FIG. 13 is an exemplary schematic explanatory diagram illustrating the operation of the wedge mechanism of the reclining device according to the embodiment, illustrating the pressing force generated by a pair of wedges. FIG. 14 is an exemplary schematic explanatory diagram illustrating the operation of the wedge mechanism of the reclining device according to the embodiment, illustrating that the intermediate member pushes up the second gear. FIG. 15 is an exemplary schematic explanatory diagram illustrating the operation of the wedge mechanism of the reclining device according to the embodiment, illustrating that the striker pin presses down the first gear. FIG. 16 is an exemplary and schematic explanatory diagram illustrating the operation of the wedge mechanism of the reclining device according to the embodiment, and illustrates that rattling can be suppressed at the meshing portion between the first gear and the second gear. FIG. 17 is an exemplary and schematic explanatory diagram illustrating the operation of the wedge mechanism of the reclining device according to the embodiment, and illustrates that the striker pin, the intermediate member, and the pair of wedges are integrally rotatable.

Below, exemplary embodiments of the present invention are disclosed. The configurations of the embodiments shown below, as well as the actions, results, and effects brought about by said configurations, are merely examples. The present invention can be realized with configurations other than those disclosed in the following embodiments, and it is possible to obtain at least one of the various effects based on the basic configuration and derivative effects.

1 is an exemplary and schematic side view showing a vehicle seat (seat) 100 to which a reclining device 10 (reclining mechanism) according to an embodiment can be applied. As shown in FIG. 1, the seat 100 is composed of a seat cushion frame 102a supporting a seat cushion 102 serving as a seat surface on which a user (passenger) sits, and a seat back 104 supported by a seat back frame 104a connected to the seat cushion frame 102a so that the angle can be adjusted in the direction of arrow A1 or arrow A2, serving as a back support surface. The seat cushion 102 is fixed to a seat slider device 110 that can move in the direction of arrow B1 or arrow B2 on a rail 108 fixed to a floor 106, which is the floor surface of the vehicle. The seat back 104 can be angle-adjusted relative to the seat cushion 102 via the reclining device 10 of this embodiment, with a rotating shaft 112 extending in the vehicle width direction as a fulcrum. The reclining device 10 is arranged inside the seat 100, for example, coaxially with the rotating shaft 112.

The amount of movement of the seat cushion 102 in the direction of the arrow B1 or the direction of the arrow B2, and the amount of angle adjustment of the seat back 104 in the direction of the arrow A1 or the direction of the arrow A2 can be adjusted by the power of a driving source such as a motor that is driven according to the operation state of the adjustment switch SW. For example, by sliding the adjustment switch SW in the direction of the arrow B1, the seat cushion 102 can be moved to a preset position or a desired position in the direction of the arrow B1. Similarly, by sliding the adjustment switch SW in the direction of the arrow B2, the seat cushion 102 can be moved to a preset position or a desired position in the direction of the arrow B2. In addition, by operating the slide lever LS to unlock, the locked state of the seat cushion 102 can be released, and the seat cushion 102 can be moved appropriately to a position in the direction of the B1 or the B2. After the seat cushion 102 has moved, the slide lever LS can be locked or the hand can be released from the slide lever LS to fix the seat cushion 102 in the desired position.

In addition, by rotating the adjustment switch SW in the direction of the arrow A1, the reclining device 10 operates, and the seat back 104 can be adjusted to a preset angle in the direction of the arrow A1 or a desired angle. Similarly, by rotating the adjustment switch SW in the direction of the arrow A2, the reclining device 10 operates, and the seat back 104 can be adjusted to a preset angle in the direction of the arrow A2 or a desired angle. In addition, by rotating the reclining lock release lever LR in a predetermined direction, the reclining lock of the reclining device 10 can be released, and the seat back 104 can be reclined to a desired angle relative to the seat cushion 102. Note that when the reclining lock release lever LR is rotated in a predetermined direction, the seat back 104 may be automatically raised to a maximum angle in the direction of the arrow A1 (forward). This operation can be realized, for example, by a spiral spring SS provided at the connection portion between the seat cushion frame 102a and the seat back frame 104a and biasing the seat back frame 104a forward (in the direction of the arrow A1). The operation of raising the seat back 104 to the maximum angle by operating the reclining lock release lever LR can be used, for example, when getting in and out of the rear seats of a two-door vehicle. At this time, the lock release operation of the slide lever LS may be automatically linked to move the seat cushion 102 to the frontmost position in the B1 direction. Also, when getting out of the vehicle, the driver's seat back 104 may be raised to the maximum angle and the seat cushion 102 may be moved to the frontmost position and locked in each position, thereby preventing the driver from sitting in the driver's seat as a crime prevention measure.

The configuration of the adjustment switch SW is just one example, and the automatic slide adjustment of the seat cushion 102 and the automatic reclining adjustment of the seat back 104 may be performed by separate switches. The location of the adjustment switch SW can be changed as appropriate, and it may be provided, for example, on the dashboard or on the steering wheel. Figure 1 shows, for example, the passenger seat of a right-hand drive vehicle, and in the driver's seat, the adjustment switch SW and reclining lock release lever LR may be located on the opposite side of the seat 100.

Figures 2 and 3 are exploded perspective views of the reclining mechanism in the reclining device 10 of this embodiment, with Figure 2 being a view seen in the direction of arrow X1 from the power drive mechanism D side, and Figure 3 being a view seen in the direction of arrow X2 from the manual drive mechanism M side. Figure 4 is an exemplary and schematic side view of an assembly diagram of the reclining device 10 (reclining mechanism). Figure 5 is an exemplary and schematic assembly diagram of the reclining device 10 (reclining mechanism) seen from the power drive mechanism D side. Figure 6 is an exemplary and schematic assembly diagram of the reclining device 10 (reclining mechanism) seen from the manual drive mechanism M side.

The reclining device 10 is composed of a power drive mechanism D (sometimes called a power drive mechanism or an adjustment mechanism) that adjusts the angle of the seat back 104 relative to the seat cushion 102 using power from a drive source (e.g., an electric motor), and a manual drive mechanism M (sometimes called a manual drive mechanism or an engagement/disengagement mechanism) that releases the reclining lock to allow manual adjustment of the angle of the seat back 104.

As shown in Figures 2 and 3, the power drive mechanism D is composed of a first gear 12, an intermediate member 14R, a wedge 14 (14a, 14b: wedge member), a striker pin 16 (drive pin), a second gear 18, a wedge spring 20 (biasing member), and a power drive shaft DS, which is the drive shaft of an electric motor, etc.

The manual drive mechanism M is composed of a second gear 18 as a common gear shared with the power drive mechanism D, a cam plate 22, a cam ring 24 (cam member), a lock member 26 (sometimes called a pole), a lower arm 28 (guide member), an outer ring 30, a lock spring 32, and a manual operation shaft MS connected to the reclining lock release lever LR. The manual operation shaft MS and the power drive shaft DS are opposed to each other and spaced apart inside the reclining device 10.

The intermediate member 14R, wedge 14 (14a, 14b), striker pin 16, second gear 18, wedge spring 20, cam plate 22, cam ring 24, locking member 26, etc. shown in Figures 2 and 3 are assembled by being sandwiched between the first gear 12 and lower arm 28 along the central axis of rotation O. Then, as shown in Figure 4, the outer peripheral ring 30 is disposed so as to surround the periphery of the lower arm 28 and the outer edge of the first gear 12. The outer peripheral ring 30 is integrated with the outer edge of the first gear 12 by a joining means such as welding, so that the assembled state of the reclining device 10 (reclining mechanism) can be maintained.

As shown in FIG. 3, the first gear 12 has two stages of first internal teeth 38a and second internal teeth 38b with different diameters in the radial direction perpendicular to the rotation center axis O, for example, by pressing, on the first surface 12A, which is one of the surfaces. In the case of FIG. 3, the first internal teeth 38a are formed on the outer diameter side of the second internal teeth 38b. That is, the diameter of the first internal teeth 38a is larger than the diameter of the second internal teeth 38b. Also, as shown in FIG. 4, the second surface 12B, which is the back side of the first surface 12A of the first gear 12, has two stages of external teeth with different diameters that protrude as a result of forming the first internal teeth 38a and the second internal teeth 38b by pressing. 4 and 5, among the two stages of external teeth formed on the second surface 12B of the first gear 12, for example, the teeth on the outer periphery can be used as the engaging external teeth 36, and the engaging external teeth 36 protrude from the outer peripheral ring 30 toward the power drive shaft DS in the direction of the arrow X2, and are configured to be connectable to, for example, a seat back frame 104a supporting a seat back 104, etc. Also, as shown in Figs. 4 and 6, a portion inside the periphery of the lower arm 28 protrudes from an opening 30a formed in the outer peripheral ring 30 toward the manual operation shaft MS in the direction of the arrow X1, and is configured to be connectable to, for example, a cushion frame supporting a seat cushion 102, etc. Note that a lock spring 32 is disposed on the outer surface of the lower arm 28, and one end 32a is engaged with an engaging protrusion 28b formed on the outer surface of the lower arm 28, and the other end 32b is engaged with the manual operation shaft MS. The lock spring 32 biases the manual operation shaft MS in a predetermined direction (for example, the clockwise direction in FIG. 6). In other words, when the manual operation shaft MS connected to the reclining lock release lever LR is manually rotated counterclockwise against the biasing force of the lock spring 32, a manual unlocked state is achieved. Also, when the reclining lock release lever LR is released, the biasing force of the lock spring 32 causes the manual operation shaft MS to rotate clockwise, returning it to the locked state.

The details of the reclining device 10 configured as described above will be explained first with reference to the power drive mechanism D.

The first gear 12 is a disk-shaped member with improved strength, which is formed by pressing or cutting a plate-shaped member (e.g., a steel plate) to form a step portion in the center. As shown in Figs. 2 and 3, the first gear 12 has a cylindrical portion 12a (first central hole) formed in the step portion by punching or drilling, and as described above, the first inner tooth 38a recessed in the direction of the arrow X2 and the second inner tooth 38b having a different diameter from the first inner tooth 38a can be easily formed by pressing the first surface 12A side using a gear-shaped press mold. At the same time, external teeth of the same diameter as the first inner tooth 38a and the second inner tooth 38b can be formed on the second surface 12B side. As described above, among the external teeth formed at this time, for example, the external tooth corresponding to the first inner tooth 38a becomes the engaging external tooth 36. These engaging external teeth 36 can be used as splines, and by engaging them with spline grooves formed in the seat back frame 104a, etc., the first gear 12 (recliner 10) can be easily and firmly connected to the seat back frame 104a, etc.

Similarly, the second gear 18 is also a disk-shaped member with improved strength, formed by, for example, pressing or cutting a plate-shaped member (e.g., a steel plate) to form a stepped portion in the center. As shown in Figs. 2 and 3, the second gear 18 has a cylindrical portion 18a (second center hole) formed by punching or drilling the stepped portion, and a first external tooth 40a protruding from the first surface 18A side (in the direction of the arrow X2) and a second external tooth 40b having a different diameter from the first external tooth 40a are formed by pressing the first surface 18A side using a gear-shaped press mold. As shown in Fig. 7, the first external tooth 40a of the second gear 18 can mesh with the first internal tooth 38a of the first gear 12, and the second external tooth 40b can mesh with the second internal tooth 38b.

FIG. 7 is an exemplary and schematic explanatory diagram of the second gear 18 including the wedge mechanism as viewed from the manual drive mechanism M. In FIG. 7, the meshing state of the first internal teeth 38a of the first gear 12 and the first external teeth 40a of the second gear 18 is shown by a dashed line. As will be described later, the second internal teeth 38b of the first gear 12 and the second external teeth 40b of the second gear 18 shown by the dashed line are not meshed in the steady state during eccentric rotation.

In the case of the reclining device 10, the first number of teeth of the first internal teeth 38a of the first gear 12 is, for example, 31, and the second number of teeth of the first external teeth 40a of the second gear 18 is, for example, 30, which is less than the first number of teeth of the first internal teeth 38a. The center of rotation of the second gear 18 is made eccentric with respect to the center of rotation of the first gear 12, and the second gear 18 is rotated while being gradually eccentric, as described in FIG. 1, so that the angle of the seat back 104 (seat back frame 104a) can be finely adjusted with respect to the seat cushion 102 (seat cushion frame 102a). Details of the eccentric rotation of the second gear 18 will be described later.

As described above, the first gear 12 is connected to the seat back 104. Therefore, for example, if an excessive impact or load is applied to the seat back 104, the impact or load acts on the meshing portion (connection portion) of the first gear 12 and the second gear 18. In other words, by ensuring sufficient connection strength between the first gear 12 and the second gear 18, it is possible to avoid damage to the gear portion. Therefore, in the reclining device 10 of this embodiment, in addition to the meshing between the first outer teeth 40a and the first inner teeth 38a, the second outer teeth 40b and the second inner teeth 38b are meshed as necessary, thereby dispersing the load acting on the connection portion between the first gear 12 and the second gear 18 and avoiding destruction. In other words, a structure is realized that can increase the strength of the reclining device 10 by two-stage meshing.

In the case of the reclining device 10 of this embodiment, as shown in FIG. 7, when the second gear 18 rotates eccentrically to realize the reclining operation (fine adjustment of the angle) in the steady state (when the vehicle is normally used), for example, the first internal teeth 38a on the outer diameter side of the first gear 12 and the first external teeth 40a on the outer diameter side of the second gear 18 rotate while partially meshing. At this time, the shapes and assembly relationship of the first gear 12 and the second gear 18 are set so that the second internal teeth 38b on the inner diameter side of the first gear 12 and the second external teeth 40b on the inner diameter side of the second gear 18 are in a non-contact state with a small gap between their tooth surfaces at any position. In other words, in the steady state, the first gear 12 and the second gear 18 rotate eccentrically using only the first internal teeth 38a and the first external teeth 40a.

In such an engagement relationship between the first internal teeth 38a and the first external teeth 40a, if a large impact or load is applied to the seat back 104, the impact or load is applied to the tooth surface where the first internal teeth 38a and the first external teeth 40a are in contact, and the shape of at least one of the tooth surfaces may be deformed. Due to the deformation of the first internal teeth 38a and the first external teeth 40a, the small gap between the second internal teeth 38b and the second external teeth 40b is closed, and the second internal teeth 38b and the second external teeth 40b are engaged. In other words, in addition to the engagement between the first internal teeth 38a and the second external teeth 40b, the engagement between the second internal teeth 38b and the second external teeth 40b is realized, increasing the engagement strength between the first gear 12 and the second gear 18.

In this case, the first internal teeth 38a and the second internal teeth 38b of the first gear 12 are formed by pressing on the same plate-like material constituting the first gear 12 with different diameters. Similarly, the first external teeth 40a and the second external teeth 40b of the second gear 18 are also formed by pressing on the same plate-like material constituting the second gear 18 with different diameters. In other words, a two-stage gear is simply formed on the plate-like material constituting the first gear 12 and the second gear 18. As a result, even if the meshing structure of the second internal teeth 38b and the second external teeth 40b that function as the "sub" when an excessive impact or load is applied is added to the meshing structure of the first internal teeth 38a and the first external teeth 40a that function as the "main" in a steady state, there is no change in the total weight of the meshing mechanism. In other words, it is possible to achieve an increase in strength while avoiding an increase in the weight of the reclining device 10. In addition, when the meshing between the first internal teeth 38a and the first external teeth 40a and the meshing between the second internal teeth 38b and the second external teeth 40b are to be performed simultaneously, it is necessary to maintain the shape of each tooth surface with high precision. On the other hand, as in this embodiment, by using the meshing between the first internal teeth 38a and the first external teeth 40a as the "main" and using the meshing between the second internal teeth 38b and the second external teeth 40b as the "secondary", only the first internal teeth 38a and the first external teeth 40a used in the steady state need to be machined with high precision. On the other hand, even if the machining precision of the second internal teeth 38b and the second external teeth 40b used auxiliary is lower than that of the first internal teeth 38a and the first external teeth 40a, no practical problems arise. As a result, it is possible to contribute to reducing processing costs and simplifying quality control.

The first internal teeth 38a, which have a larger diameter than the second internal teeth 38b, have the strength to withstand greater impacts and loads than the second internal teeth 38b. Therefore, by using the first internal teeth 38a, which have a larger diameter than the second internal teeth 38b, in a steady state, the allowable value of the impacts and loads of the reclining device 10 in a steady state can be improved, contributing to improved quality. In addition, a larger diameter makes it easier to obtain high precision when machining the tooth surface, and can contribute to improving smoothness and reducing the generation of contact noise when the first internal teeth 38a and the first external teeth 40a mesh together.

Next, the manual drive mechanism M will be described using Figures 2, 3, and 8. Note that Figure 8 shows the lower arm 28 in a transparent state, with the lock member 26 side seen in the direction of the arrow X1 from the manual operation shaft MS side.

As described above, when forming the first external teeth 40a and the second external teeth 40b used in the power drive mechanism D in the second gear 18 used in the manual drive mechanism M, the internal teeth recessed toward the manual drive mechanism M are formed by a gear-shaped press mold. These internal teeth are the locking internal teeth 42a that engage with the locking member 26 and the engaging internal teeth 42b that engage with a lock adjustment plate (not shown) that can be appropriately positioned and can set and adjust the lock angle of the seat back 104. In other words, the first external teeth 40a and the locking internal teeth 42a of the second gear 18 and the second external teeth 40b and the engaging internal teeth 42b have the same diameter and the same rotation center axis O, and are molded and arranged on the front and back sides in the axial direction. As a result, it is possible to contribute to simplifying the manufacturing process when forming the second gear 18, improving efficiency, and reducing costs. In addition, the first external teeth 40a and second external teeth 40b that can be used with the power drive mechanism D, and the locking internal teeth 42a and the engaging internal teeth 42b that can be used with the manual drive mechanism M are arranged on the front and back of the second gear 18, which makes it possible to save space when arranging multiple gears and to make the second gear 18 smaller (smaller in diameter).

Figure 8 is an exemplary schematic diagram illustrating the meshing state between the locking member 26 of the manual drive mechanism M and the locking internal teeth 42a of the second gear 18.

The manual drive mechanism M is a mechanism that releases the lock of the seat back 104 relative to the seat cushion 102 so that the seat back 104 can be freely tilted relative to the seat cushion 102 when the angle of the seat back 104 is adjusted manually. The manual drive mechanism M is also a mechanism that locks the second gear 18 when the angle of the seat back 104 is automatically adjusted by the power drive mechanism D and when the adjusted angle state of the seat back 104 relative to the seat cushion 102 is maintained.

In the case of the reclining device 10 (reclining mechanism) of this embodiment, the locked state is achieved by meshing the locking internal teeth 42a of the second gear 18 with the locking member 26, and the unlocked state is achieved by disengaging them.

As shown in Figures 2, 3, and 8, the locking members 26 are arranged on the inner periphery side of the locking internal teeth 42a of the second gear 18, for example at equal intervals, so as to be movable in the outer and inner radial directions. In the present embodiment, four locking members 26 are arranged at 90° intervals, but it is the two locking members 26 arranged opposite each other that actually lock the rotation of the second gear 18. The number of locking members 26 can be changed as appropriate, as long as the strength is sufficient to maintain the locked state of the seat back 104 relative to the seat cushion 102.

The locking member 26 is a block-shaped member with a roughly rectangular parallelepiped shape. In the case of the reclining device 10, the main locking member 26A, which performs the locking operation in a steady state, and the sub-locking member 26B, which performs the auxiliary locking operation when a high load is applied, are arranged alternately in the circumferential direction. The main locking member 26A is structured to include a roughly hexagonal cam chip 26C.

When the reclining device 10 is assembled, each locking member 26 is supported (guided) by a guide wall 48a extending radially in the lower arm 28, which is a part of the guide portion 48 that protrudes toward the power drive mechanism D, so that it can slide radially. The lower arm 28 has an opening 28a in the center through which the manual operation shaft MS can be inserted, and guide portions 48 are formed around the opening 28a at equal intervals (for example, 90° intervals). Therefore, each locking member 26 slides while being sandwiched between the guide walls 48a of the adjacent guide portions 48. The main locking member 26A and the cam chip 26C are separate parts, and are arranged loosely between the guide walls 48a as shown in FIG. 8.

Each locking member 26 has a dowel 47a that is inserted into the cam groove 44 of the cam plate 22, a leg 47b that abuts against the ridge 46 of the cam ring 24, and a locking tooth 47c that engages with the locking internal tooth 42a of the second gear 18.

The cam plate 22 is a ring-shaped part with cam grooves 44, with an opening 22a formed in the center, and cam grooves 44 punched out on the outer periphery of the opening 22a, the number of which corresponds to the number of locking members 26. As shown in Figures 3 and 8, the cam grooves 44 are grooves that extend in the approximate circumferential direction of the cam plate 22, and the cam surface on the outer periphery of the groove forms an inclined portion 44a that rises toward the inner diameter side.

The cam plate 22 is formed with, for example, two connection holes 22b, and the cam plate 22 and the cam ring 24 are integrated by inserting a connection protrusion 24b formed at a position corresponding to the connection hole 22b on the outer periphery side of the opening 24a of the cam ring 24. A manual operation shaft MS is inserted and fixed into the opening 24a of the cam ring 24. Therefore, when the reclining lock release lever LR is operated and the manual operation shaft MS rotates, the cam plate 22 rotates integrally with the cam ring 24. The cam ring 24 is provided with a plurality of peaks 46 on its outer periphery that can come into contact with the legs 47b of the locking member 26, and is provided with valleys 46a between adjacent peaks 46 that can receive the legs 47b and the cam chip 26C.

Inside the reclining device 10, a part of the striker pin 16, including the flange, that penetrates the cylindrical portion 18a of the second gear 18 faces the cam plate 22 at a distance in the axial direction of the power drive shaft DS (manual operation shaft MS). At this time, by making the axial separation distance between the striker pin 16 and the cam plate 22 shorter than the axial length of the connecting protrusion 24b of the cam ring 24, even if a force acts to axially separate the cam plate 22 from the cam ring 24, the striker pin 16 can prevent the cam plate 22 from separating (falling off) from the cam ring 24.

In the manual drive mechanism M configured as described above, when the reclining lock release lever LR is not operated, that is, when the manual operation shaft MS is returned to the locked position by the biasing force of the lock spring 32. In this case, as shown in FIG. 8, the peak 46 of the cam ring 24 does not contact the leg 47b of the main lock member 26A, but contacts the leg 26Ca of the cam chip 26C, causing the cam chip 26C to contact the guide wall 48a. Then, the main lock member 26A and the cam chip 26C slide in the outer diameter direction. As a result, the main lock member 26A moves smoothly to the locked position without rattling between the guide wall 48a due to the wedge effect of the cam chip 26C. In other words, the lock teeth 47c of the main lock member 26A mesh with the locking internal teeth 42a of the second gear 18, and the locked state is established. In this embodiment, the number of teeth on the locking internal teeth 42a of the second gear 18 is 30, so the angle of the seat back 104 can be locked every 12°.

In this case, the legs 47b of the sub-lock member 26B are also pressed in the outer diameter direction by the crests 46 of the cam ring 24 and move to the locked position, but there is a gap between the cam ring 24 and the sub-lock member 26B. Therefore, the sub-lock member 26B moves to the locked position in a free state. In this way, by configuring the sub-lock member 26B to be freely movable, it is possible to effectively prevent the main lock member 26A from rattling due to the cam chip 26C and to move it smoothly to the locked position. Specifically, the crests 46 of the cam ring 24 first press the legs 47b of the main lock member 26A located at the diagonal position, and then press the legs 26Ca of the cam chip 26C to move the main lock member 26A to the locked position. Finally, the crests 46 of the cam ring 24 move away from the legs 47b of the main lock member 26A and press the legs 26Ca of the cam chip 26C to complete the locked state. As a result, as shown in FIG. 8, the main locking member 26A can be moved smoothly to the locking position without bias. In addition, when an impact or load is applied to the seat back 104, the sub-locking member 26B can auxiliary engage with the locking internal teeth 42a to receive the load.

On the other hand, when the reclining lock release lever LR is operated, that is, when the manual operation shaft MS is operated to the unlocked position against the biasing force of the lock spring 32. In this case, the peak 46 of the cam ring 24 is released from the opposing relationship with the leg 47b of the main lock member 26A, and the leg 47b fits into the valley 46a. Also, the adjacent peak 46 is released from the leg 26Ca of the cam chip 26C, and the leg 26Ca fits into the valley 46a. At this time, the cam plate 22 rotates together with the cam ring 24, so that the cam groove 44 moves relative to the dowel 47a of the main lock member 26A, and the dowel 47a starts to climb the inclined portion 44a. As a result, the main lock member 26A is pulled up in the inner diameter direction and moves to the unlocked position. In other words, the locking teeth 47c of the main lock member 26A are released from the locking inner teeth 42a, and the unlocked state is established.

In this case, the dowel 47a of the sub-lock member 26B also climbs the inclined portion 44a of the cam groove 44 as the cam plate 22 rotates. As a result, the sub-lock member 26B also moves to the unlocked position.

In this way, the second gear 18 can rotate freely when the locking member 26 is moved to the unlocked position by operating the reclining lock release lever LR. In other words, the first gear 12, which is connected to the second gear 18 via the first external teeth 40a and the first internal teeth 38a, can rotate freely relative to the lower arm 28. As a result, the seat back frame 104a (seat back 104) connected to the first gear 12 can freely swing (recline) relative to the seat cushion frame 102a (seat cushion 102) connected to the lower arm 28. For example, the seat back 104 can be freely reclined by pushing it with a hand. Also, when the reclining lock release lever LR is released, each locking member 26 is pressed against the crest 46 of the cam ring 24 and moves to the locked position shown in FIG. 8, so that the rotation of the second gear 18 and the rotation of the first gear 12 are restricted. As a result, the angle of the seat back 104 is fixed relative to the seat cushion 102.

Next, we will explain the structure of the reclining device 10 (reclining mechanism) of this embodiment that suppresses rattling of the seat back 104 (seat back frame 104a) relative to the seat cushion 102 (seat cushion frame 102a).

As described above, in the reclining device 10 of this embodiment, the second gear 18 and the first gear 12 rotate eccentrically relative to each other, so that the seat back frame 104a (seat back 104) realizes power driving by driving the driving source. In addition, the first gear 12 rotates eccentrically freely relative to the second gear 18, whose rotation is restricted, to realize manual driving. Therefore, it is preferable that the meshing portions of the tooth surfaces of the first gear 12 and the second gear 18, which rotate eccentrically relative to each other, mesh with each other without generating any extra play (gap). The reclining device 10 (reclining mechanism) of this embodiment uses a wedge mechanism to realize stable eccentric rotation between the first gear 12 and the second gear 18 during power driving and manual driving without generating any play (gap). In addition to the first gear 12 and the second gear 18, the reclining device 10 (reclining mechanism) realizes a wedge mechanism using an intermediate member 14R (third wedge member), a wedge 14a (first wedge member), a wedge 14b (second wedge member), a striker pin 16 (drive pin), the second gear 18, and a wedge spring 20.

2, 3, 7, and 9 to 17, we will explain the eccentric rotation structure using the wedge mechanism of the reclining device 10 and how stable eccentric rotation can be achieved regardless of whether or not a load (weight) is input to the seat back frame 104a (seat back 104). Note that FIG. 12 is a cross-sectional view taken along line C-C of FIG. 7, and is an exemplary and schematic cross-sectional view showing the state in which the intermediate member 14R, wedge 14a, wedge 14b, striker pin 16, and wedge spring 20 are assembled in addition to the first gear 12 and second gear 18.

Figure 9 is an exemplary and schematic plan view showing the shape of intermediate member 14R.

9, the intermediate member 14R is a plate-shaped member having a substantially elliptical ring shape in which the length x1 in the x direction is slightly longer than the length y1 in the y direction, and has a shape capable of containing the wedge 14 (wedges 14a, 14b) and the striker pin 16 on the inner peripheral side. The intermediate member 14R also has a first engagement portion 50 on at least a part of the circumferential direction of the ring inner peripheral portion 14Ra. The first engagement portion 50 includes, for example, a long piece convex portion 50a and a short piece convex portion 50b that protrude radially inward of the intermediate member 14R. In the case of FIG. 9, the long piece convex portion 50a and the short piece convex portion 50b are formed in opposing positions separated by 180°, for example, and the long piece convex portion 50a has, for example, a length y2 in the y direction longer than a length y3 and a width x2 in the x direction shorter than a width x3 than the short piece convex portion 50b. In addition, on the inner circumference 14Ra of the ring, wedge guides 52a and 52b capable of accommodating the wedges 14a and 14b are formed on the left and right sides of the long piece protrusion 50a in the circumferential direction. The wedge guides 52a and 52b are, for example, notches in a substantially arc shape that open toward the radially inner side of the intermediate member 14R, and are slightly larger than the shapes of the wedges 14a and 14b. As shown in FIG. 12, the intermediate member 14R is accommodated in a state in which a portion of the outer circumference 14Rb can come into contact with the cylindrical portion 18a of the second gear 18.

Figure 10 is an exemplary and schematic plan view showing the shape of one (wedge 14b) of a pair of wedges 14 that constitute the wedge mechanism of the reclining device 10. Note that the shape of the other of the pair of wedges 14, wedge 14a, is symmetrical to wedge 14b shown in Figure 10, so we will explain wedge 14b as a representative and omit the explanation of wedge 14a.

The wedge 14b (wedge 14a) is a plate-shaped part having a substantially arc-shaped shape, and the arc-shaped inner peripheral portion 54a can contact the outer peripheral surface of the first cylindrical portion 16a of the striker pin 16 as shown in Figs. 7 and 12, and the arc-shaped outer peripheral portion 54b can contact the wedge guide portion 52b (52a) of the intermediate member 14R. In addition, the end portion 54c and the end portion 54d, which are the outer periphery sandwiched between the inner peripheral portion 54a and the outer peripheral portion 54b, are formed on a part of the end portion 54c with, for example, an arc-shaped spring engagement portion 54e that can engage with the hook 20a formed on the end portion of the substantially C-shaped wedge spring 20 shown in Figs. 2 and 7. The symmetrical wedge 14a also has a similar spring engagement portion 54e. The wedge spring 20 urges the wedge 14b in the direction of the arrow +WS and urges the wedge 14a in the direction of the reverse arrow WS. That is, the wedge 14b is biased along the wedge guide portion 52b, and the wedge 14a is biased along the wedge guide portion 52a by the wedge spring 20 in a direction away from each other. Here, the width W1 of the end 54d of the wedge 14b is set narrower than the width W2 of the end 54c at the opposing position, and the wedge 14b is biased in the direction of the arrow +WS by the wedge spring 20, so that the wedge 14b functions as a wedge that is pressed between the contact surface of the wedge guide portion 52b and the first cylindrical portion 16a of the striker pin 16. Similarly, the wedge 14a is biased in the direction of the reverse arrow WS by the wedge spring 20, so that the wedge 14a functions as a wedge that is pressed between the contact surface of the wedge guide portion 52a and the first cylindrical portion 16a of the striker pin 16.

Figure 11 is an exemplary and schematic diagram showing the shape of the striker pin 16, where the upper part is a plan view seen from the power drive shaft DS side, and the lower part is a cross-sectional view taken along line D-D of the plan view.

As shown in the plan view at the top and the cross-sectional view at the bottom of FIG. 11, the striker pin 16 is a cylindrical member having a first cylindrical portion 16a, a second cylindrical portion 16b, and a pair of protruding flange portions 16c. The first cylindrical portion 16a has a larger diameter than the second cylindrical portion 16b, and as shown in FIG. 7 and FIG. 12, the wedge 14a and the inner peripheral portion 54a of the wedge 14b can contact the first cylindrical portion 16a. The second cylindrical portion 16b can be inserted with the outer peripheral surface of the second cylindrical portion 16b in contact with the inner peripheral surface of the cylindrical portion 12a (first center hole) of the first gear 12, and is supported so as to rotate smoothly and stably with respect to the first gear 12.

A hexagonal hole 16d, for example, is formed in the center of the cylindrical striker pin 16 to correspond to the shape of the power drive shaft DS to be inserted. This hole 16d functions as a spline extending in the directions of arrows X1 and X2, and provides a strong spline fit when the power drive shaft DS, which has a hexagonal cross section and is the drive shaft of a drive source such as an electric motor, is inserted during automatic reclining adjustment. In other words, the power drive shaft DS and the striker pin 16 can rotate together.

The striker pin 16 is provided on its outer circumferential surface with a second engaging portion 56 (long piece recess 56a, short piece recess 56b) that can engage with the first engaging portion 50 (long piece protrusion 50a and short piece protrusion 50b) formed on the intermediate member 14R. In the case of FIG. 11, the long piece recess 56a and short piece recess 56b are formed in opposing positions (positions 180° apart) corresponding to the long piece protrusion 50a and short piece protrusion 50b. The width x4 of the long piece recess 56a and the width x5 of the short piece recess 56b are formed to be the same as or slightly wider than the width x2 of the corresponding long piece protrusion 50a and the width x3 of the short piece protrusion 50b. In other words, the striker pin 16 and the intermediate member 14R are engaged as shown in FIG. 7 and can rotate together.

The flange portion 16c formed on the outer peripheral surface of the striker pin 16 protruding radially outward supports the intermediate member 14R and the pair of wedges 14a, 14b in a direction perpendicular to the rotation direction of the striker pin 16 (the front-to-back direction of the paper in FIG. 11, the X2 direction), as shown in FIG. 7 and FIG. 12. In other words, it prevents the intermediate member 14R and the wedges 14a, 14b from falling off in the direction of the arrow X1, allowing the wedge action to be performed stably.

The operation of the wedge mechanism configured in this manner will be explained with reference to Figures 13 to 17.

First, we will explain how the first gear 12 and the second gear 18, which are in an eccentric relationship, are maintained in a state in which they can rotate eccentrically smoothly without rattling (without forming any greater gap than necessary) due to the wedge effect (wedging) of the wedge mechanism.

As mentioned above, the wedges 14a and 14b are biased in the direction away from each other (the +WS and -WS directions) by the wedge spring 20 (see FIG. 7, partially omitted in FIG. 13). In other words, the outer peripheral portion 54b of the wedges 14a and 14b presses the wedge guide portion 52a (52b) of the intermediate member 14R in the direction of the arrow E1 (E2) with which it comes into contact. As a result, the intermediate member 14R is pushed up in the direction of the arrow Y1. Therefore, as shown in FIG. 14, the intermediate member 14R (outer peripheral surface 14Rb) arranged on the cylindrical portion 18a of the second gear 18 biases and pushes up the second gear 18 (the inner surface of the cylindrical portion 18a) in the direction of the arrow Y1.

Similarly, the inner peripheral portions 54a of the wedges 14a, 14b press the first cylindrical portion 16a of the striker pin 16 in contact with it in the directions of the arrows F1, F2, as shown in FIG. 13. As a result, the striker pin 16 is pushed down in the direction of the arrow Y2. Therefore, as shown in FIG. 15, the striker pin 16 (second cylindrical portion 16b) arranged in the cylindrical portion 12a of the first gear 12 urges the first gear 12 (cylindrical portion 12a) in the direction of the arrow Y2.

As a result, as shown in FIG. 16, the first gear 12 is biased in the direction of the arrow Y2 relative to the second gear 18, which is biased in the direction Y1, and the first internal teeth 38a of the first gear 12 and the first external teeth 40a of the second gear 18 can maintain a meshed state, for example, between the ranges G1-G2, without creating a gap (without rattling).

Let us consider a case where a large load is input to the seat back 104 in the wedge mechanism of the reclining device 10 configured in this way. For example, this is the case where a load from the spiral spring SS (see Figure 1) that automatically raises the seat back 104 forward when the reclining device 10 is manually operated is input to the wedge mechanism.

First, as a comparative example, let us consider a case where wedges 14a and 14b are present between the striker pin 16, which operates integrally with the first gear 12, and the second gear 18, without the intermediate member 14R. In this case, the first gear 12 may be pushed up in a direction based on the biasing direction by the biasing force of the spiral spring SS, causing axial misalignment. As a result, the first gear 12 may move away from the second gear 18, causing a gap (backlash) in the meshing portion. In addition, the first gear 12 and the striker pin 16 bias the second gear 18 through the wedges 14a and 14b. As a result, for example, when the biasing force of the spiral spring SS is applied, if the striker pin 16 tries to rotate together with the first gear 12, the frictional force between the striker pin 16 in contact with the inner peripheral surface side of the wedge 14b and the frictional force between the second gear 18 in contact with the outer peripheral side of the wedge 14b may increase, and the wedge 14b may not be able to move. As a result, the biasing force of the wedge spring 20 separates the wedges 14a and 14b, for example, by pushing the wedge 14b in a clockwise direction, and the wedge effect cannot be exerted. In this case, even if the striker pin 16 rotates, the gap between the wedges 14a and 14b is only narrowed. In this way, the biasing force of the spiral spring SS creates a situation in which the wedge effect of the wedge 14b is difficult to generate, so that a gap is likely to occur in the meshing portion between the first gear 12 and the second gear 18, and the second gear 18 (seat cushion 102) side is not firmly locked to the first gear 12 (seat back 104) side. In other words, there is a possibility that rattling will occur in the meshing portion between the first gear 12 and the second gear 18. Therefore, for example, when a person places his or her hand on the seat back 104 and pushes it, even though the first gear 12 and the second gear 18 should be locked (sufficiently engaged), the seat back 104 can easily swing at an angle corresponding to the amount of play in the meshing portion between the first gear 12 and the second gear 18.

On the other hand, in the case of the reclining device 10 (reclining mechanism) of this embodiment, as described above, the wedge 14a and the wedge 14b are arranged between the striker pin 16 that rotates integrally with the first gear 12 and the intermediate member 14R that can rotate integrally with the striker pin 16. In this structure, when the urging force of the spiral spring SS is applied, the striker pin 16 tries to rotate together with the first gear 12, and the frictional force at the contact portion between the inner periphery of the wedge 14a (14b) and the striker pin 16 increases. Similarly, the frictional force at the contact portion between the outer periphery of the wedge 14a (14b) and the intermediate member 14R increases. However, since the striker pin 16, the intermediate member 14R, and the wedges 14a and 14b can rotate simultaneously, a gap is maintained between the wedges 14a and 14b (the relative positional relationship is maintained). In other words, the wedge function is maintained, and the meshed state (locked state) between the first gear 12 and the second gear 18 is maintained as shown in FIG. 16, so that the seat back 104 can be prevented from rocking even if the seat back 104 is pushed with a hand.

When the power drive is performed by operating the drive source, the power drive shaft DS rotates due to the operation of the drive source, and the striker pin 16, which is spline-fitted, rotates. When the power drive shaft DS rotates, for example, clockwise, the striker pin 16 pulls the wedge 14a in the rotational direction, and the wedge 14a pulls the intermediate member 14R in the rotational direction to rotate it. At this time, the wedge 14a pushes the wedge spring 20, and further pushes the wedge 14b. In other words, the striker pin 16 and the intermediate member 14R move the wedge 14b, realizing the wedge function. In this case, the striker pin 16, the intermediate member 14R, the wedge 14a, and the wedge 14b rotate together while maintaining a gap between the wedges 14a and 14b due to the biasing force of the wedge spring 20 (while maintaining the meshed (locked) state between the first gear 12 and the second gear 18).

At this time, as described above, the first number of teeth of the first internal teeth 38a of the first gear 12 and the second number of teeth of the first external teeth 40a are offset by, for example, one tooth, so that the first gear 12 and the second gear 18 start to rotate eccentrically while the meshing between the first internal teeth 38a and the first external teeth 40a is offset by one tooth during one rotation of the striker pin 16. In other words, the first gear 12 is eccentrically rotated in the forward direction by the forward drive of the power drive shaft DS, and the reclining angle of the seat back 104 is adjusted. Similarly, when the power drive shaft DS is driven in the reverse direction (counterclockwise), the striker pin 16, the intermediate member 14R, the wedge 14a, and the wedge 14b rotate together while maintaining the meshing (locked) state between the first gear 12 and the second gear 18. As a result, by driving the power drive shaft DS in the reverse direction, the first gear 12 is eccentrically rotated in the reverse direction, and the reclining angle of the seat back 104 can be adjusted in the reverse direction.

In this way, the striker pin 16, intermediate member 14R, wedge 14a, and wedge 14b rotate together while maintaining their relative positional relationship, and the first gear 12 rotates eccentrically with respect to the second gear 18 while maintaining the meshed (locked) state between the first gear 12 and the second gear 18, allowing smooth angle adjustment.

As described above, according to the reclining device 10 of this embodiment, even when a load (weight) due to the biasing force of the spiral spring SS or the like is input to the seat back 104 (seat back frame 104a), the wedge mechanism can be made to function sufficiently to prevent a gap from occurring in the meshing portion between the meshing first gear 12 and second gear 18. In other words, rattling of the seat back 104 can be suppressed. In addition, smooth angle adjustment can be achieved without causing rattling of the seat back 104 (seat back frame 104a).

In the above embodiment, the load (weight) input to the seat back 104 (seat back frame 104a) is caused by the spiral spring SS that generates a biasing force for automatically raising the seat back 104 forward during manual operation. In another example, even when a heavy user leans against the seat back 104 and a large load is input, the striker pin 16, intermediate member 14R, wedge 14a, and wedge 14b can rotate together, and the first gear 12 and the second gear 18 can be maintained in a meshed (locked) state in the same way as when the biasing force of the spiral spring SS is input, and the same effect can be obtained.

In the above embodiment, the first gear 12 is connected to the seat back frame 104a (seat back 104) side, and the second gear 18 is connected to the seat cushion frame 102a (seat cushion 102) side. In another embodiment, the second gear 18 may be connected to the seat back frame 104a (seat back 104) side, and the first gear 12 may be connected to the seat cushion frame 102a (seat cushion 102) side, and the same effect can be obtained. In the above embodiment, the striker pin 16 (drive pin) is inserted into the cylindrical portion 12a (first center hole) of the first gear 12, and the intermediate member 14R is inserted into the cylindrical portion 18a (second center hole) of the second gear 18. In another embodiment, the striker pin 16 may be inserted into the second gear 18 side, and the intermediate member 14R may be inserted into the first gear 12 side, and the same effect can be obtained.

In addition, in the above-described embodiment, the reclining device 10 is applied to a reclining seat for a vehicle, but it is not limited to a vehicle seat. For example, the reclining device 10 of this embodiment can be applied to any seat that can be reclined using power from a drive source, such as an airplane seat, a ship seat, or a seat used in various attractions, and the same effect can be obtained.

Although the embodiments and variations of the present invention have been described, these embodiments and variations are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and variations are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents as set forth in the claims.

10...recliner, 12...first gear, 14, 14a, 14b...wedge, 14R...intermediate member, 16...striker pin (drive pin), 18...second gear, 18A...first surface, 18B...second surface, 22...cam plate, 24...cam ring (cam member), 26...lock member, 28...lower arm (guide member), 30...outer ring, 38a...first internal teeth, 38b...second internal teeth, 40a...first external teeth, 40b...second external teeth, 102...seat cushion, 102a...seat cushion frame, 104...seat back, 104a...seat back frame, D...power drive mechanism, DS...power drive shaft, LR...recliner lock release lever, M...manual drive mechanism, MS...manual operation shaft.

Claims (3)

A seat back frame supporting the seat back;
a seat cushion frame supporting the seat cushion;
a drive source attached to either the seat back frame or the seat cushion frame;
a reclining mechanism that adjusts the angle of the seat back frame relative to the seat cushion frame by using power from the driving source;
Equipped with
The reclining mechanism includes:
a first gear having internal teeth and connected to one side of the seat back frame or the seat cushion frame;
a second gear connected to the other side of the seat back frame or the seat cushion frame, the second gear having external teeth capable of meshing with the internal teeth and eccentrically rotatable with respect to the first gear;
a drive pin connected to the drive source, a portion of which is inserted into a first center hole formed in one of the first gear or the second gear and rotatably supported therein;
a ring-shaped intermediate member having an inner circumferential side surrounding the drive pin and an outer circumferential side in contact with a second center hole formed in the other of the first gear or the second gear;
a pair of wedge members disposed between the drive pin and the intermediate member and shaped to be wedgeable in a direction away from each other along an inner circumferential surface of the intermediate member;
a biasing member that biases the pair of wedge members in the separating direction;
Equipped with
When the biasing member biases the pair of wedge members in a separating direction, the pair of wedge members press the intermediate member and the drive pin in a separating direction in which the intermediate member and the drive pin are separated from each other, and in a direction toward an outer diameter of the second gear,
The intermediate member is
biasing the second gear in a first direction in an outer radial direction;
The drive pin is
biasing the first gear in a second direction opposite to the first direction;
Reclining device. The reclining device according to claim 1, wherein a first engagement portion is formed on at least a portion of the circumferential direction of the inner circumferential surface of the intermediate member, and a second engagement portion that can engage with the first engagement portion is formed on at least a portion of the circumferential direction of the outer circumferential surface of the drive pin. The reclining device according to claim 1 or 2, wherein the drive pin is formed with a flange portion that protrudes radially outward, and the intermediate member and the pair of wedge members are supported by the flange portion in a direction perpendicular to the rotation direction of the drive pin.

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