WO2008130075A1

WO2008130075A1 - Recliner assembly

Info

Publication number: WO2008130075A1
Application number: PCT/KR2007/003025
Authority: WO
Inventors: Su-Min Chae; Heon-Pil Lim; Jung-Hyung Cho
Original assignee: Austem Co., Ltd.
Priority date: 2007-04-20
Filing date: 2007-06-21
Publication date: 2008-10-30

Abstract

A recliner assembly is disclosed. The recliner assembly of the present invention includes a first recliner (100) and a shaft (110). The first recliner includes a first holder, which receives a first operating cam and first lock gears therein and has first lock gear guide parts, and a first sector gear, which has first internal gear teeth. The first internal gear teeth engage with the first lock gears when the first lock gears conduct the locking operation. The shaft is coupled to the first operating cam. Furthermore, at least one first key slot (143) is formed in the first shaft hole, and a first locking key (112) is provided on the shaft at a position corresponding to the first key slot. A gap is defined between the first key slot and the first locking key such that the first operating cam is slightly rotatable with respect to the shaft.

Description

Description RECLINER ASSEMBLY

Technical Field

[1] The present invention relates, in general, to recliner assemblies and, more particularly, to a recliner assembly which includes a plurality of lock gears and an operating cam for operating the lock gears and is constructed such that a skipping phenomenon is prevented from occurring when the lock gears conduct a locking operation. Background Art

[2] Generally, seats, which enable occupants to sit thereon, are provided in vehicles.

Such a vehicle seat comprises a seat cushion, which supports the weight of an occupant, and a seat back, which supports the back of the occupant.

[3] Furthermore, a seat track is provided under the seat cushion, such that the seat is adjustable forwards or backwards by manipulating an operating lever. Therefore, an occupant can appropriately adjust the position of the seat forwards or backwards depending on his/her body type or individual preference.

[4] Typically, the seat back is installed so as to be rotatable with respect to the seat cushion using a hinge to realize a structure such that the occupant can adjust the inclination of the seat back to meet his/her convenience. For this, the seat is convertible between a locked state, in which the seat back is at a fixed angle with respect to the seat cushion, and an unlocked state, in which the seat back is rotatable with respect to the seat cushion. To achieve the above-mentioned purpose, a recliner, which makes it possible for the seat to maintain a locked state or an unlocked state or to switch therebetween, is provided in the seat.

[5] Fig. 1 is a view showing the construction of a typical seat for vehicles. Fig. 2 is a side sectional view showing an example of a recliner for vehicles according to a conventional technique.

[6] As shown in Fig. 1, in the conventional recliner assembly, a first recliner 10 is coupled to a first shaft 14, and a second recliner 10' is coupled to a second shaft 14'. The first shaft 14 and the second shaft 14' are coupled to each other through a rod 40 by a coupling method such as welding.

[7] In detail, the recliners 10 and 10' are installed at respective opposite positions in a seat cushion, and, thereafter, the shafts 14 and 14' are respectively coupled to the recliners 10 and 10'. Subsequently, the first shaft 14 is first bonded to the rod 40 by a method such as welding, and the second shaft 14' is secondarily bonded to the rod 40.

[8] Here, a worker must bond the first shaft 14 and the second shaft 14' to the rod 40 such that central axes thereof are precisely aligned with each other. As such, because the assembly is very inconvenient, there are problems in that the manufacturing time is increased, productivity is reduced, and the proportion of defective products is high.

[9] Furthermore, due to the process of coupling the first shaft 14, the second shaft 14' and the rod 40 with each other through the welding processes, there are problems in that the process of manufacturing the recliner assembly is complicated, and the manufacturing cost thereof is increased. In addition, if the seat back too frequently conducts the reclining operation, junctions between the shafts 14 and 14' and the rod 40 may be damaged, so that there is the possibility of a safety hazard.

[10] Meanwhile, as shown in Fig. 2, the conventional recliner 10 for vehicles includes a lower plate 11, which is fastened to one end of the seat cushion of the vehicle seat, an upper plate 12, which is installed in the lower end of the seat back, an operating member 13, which is provided between the lower plate 11 and the upper plate 12, and a shaft 14, which is coupled to the lower plate 11 and serves as an operating force applying means. The recliner 10 further includes an operating lever 30 and a lever spring.

[11] The operating member 13 is provided in spaces defined between the lower plate 11 and the upper plate 12. A lock gear 20, on the outer surface of which locking teeth 19 are formed, is interposed between the operating member 13 and the upper plate, such that a locked state or an unlocked state are selected through coupling or separation between the locking teeth 19 and upper teeth 18 formed in the upper plate 12.

[12] Furthermore, the conventional recliner further includes an operating cam 21, which is coupled to the shaft 14 and is constructed such that, when the operating cam 21 pushes the lock gear 20 in a radial direction, the upper teeth 18 and the locking teeth 19 engage with each other. In addition, a lock gear guide is integrally formed in the lower plate such that the lock gear 20 can smoothly and linearly reciprocate under the guidance of the lock gear guide.

[13] Therefore, in a state in which the upper teeth 18 and the locking teeth 19 are locked to each other, when the operating lever 30 is manipulated, the seat back enters an unlocked state. At this time, the occupant maintains the unlocked state of the seat back and adjusts the position of the seat back forwards or backwards. Thereafter, the operating lever 30 is released. Then, the operating cam 21 is rotated by a return spring (not shown), so that the lock gear 20 is pushed by the operating cam 21, thereby the upper teeth 19 and the locking teeth 19 enter a state of being locked to each other again.

[14] Meanwhile, the shaft 14 and the operating cam 21 are integrally coupled to each other by a method such as caulking (14c) or welding. Furthermore, the shafts of the recliners, which are disposed at opposite positions, are integrally coupled to each other through the connection rod (40 of Fig. 1), which is connected between the shafts by welding.

[15] As such, in the case where the shaft 14, the operating cam 21 and the connection rod (40 of Fig. 1) are integrally coupled to each other, the speed at which the operating cam 21 is rotated by the return spring is reduced by the inertia force of the shaft 14, the operating cam 21, the connection rod (40 of Fig. 1) and the operating lever 30. Therefore, when the upper teeth 18 and the locking teeth 19 are locked to each other, a skipping phenomenon occurs.

[16] In other words, although the operating cam 21 is rotated by the return spring when the operating lever 30 is released after the seat back has been adjusted, due to the inertial force of the operating lever and the shaft 4, which is integrally coupled to the operating cam 21, the inertial force providing a tendency to maintain the stationary state, the rotation of the operating cam 21 is impeded, with the result that the upper teeth 18 and the locking teeth 19 are incompletely locked to each other for a short time.

[17] At this time, if external force is applied to the seat back forwards or backwards, the skipping phenomenon, in which the upper teeth 18 and the locking teeth 19 rub against each other, is generated. Therefore, there are problems in that a safety hazard is presented to the occupant, and the upper teeth 18 and the locking teeth 19 are excessively worn. Disclosure of Invention

Technical Problem

[18] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a recliner assembly which can prevent a skipping phenomenon, thus preventing a safety hazard from being presented to an occupant, and which is constructed such that, when opposite recliners are aligned with each other during an assembly process, even if tolerance exists within a predetermined range, a shaft can be coupled to the recliners, and such that torsional stress is prevented from being applied to the shaft. Technical Solution

[19] In order to accomplish the above object, the present invention provides a recliner assembly, comprising: a first recliner, including a first holder, receiving therein a first operating cam, through a central portion of which a first shaft hole is formed, the first holder receiving therein a plurality of first lock gears around the first operating cam, with a plurality of first lock gear guide parts provided in the first holder to guide the first lock gears such that the first lock gears reciprocate depending on rotation of the first operating cam to conduct a locking or unlocking operation, and a first sector gear rotatably coupled to the first holder, with a first shaft passing hole formed through a central portion of the first sector gear, and first internal gear teeth formed along a circular rim of the first sector gear, the first internal gear teeth engaging with the first lock gears when the first lock gears conduct the locking operation; and a shaft coupled to the first operating cam to provide a rotating force thereto, wherein at least one first key slot is formed in a circumferential inner surface of the first shaft hole of the first operating cam, a first locking key is integrally provided on the shaft at a position corresponding to the first key slot so that the first locking key engages with the first key slot, and a gap is defined between the first key slot and the first locking key such that the first operating cam is rotatable with respect to the shaft.

[20] The first key slot may comprise three first key slots formed around the first shaft hole at positions spaced apart from each other at regular angular intervals.

[21] The recliner assembly may further comprise: a rod coupled to one end of the shaft such that a central axis of the rod is aligned with a central axis of the shaft; and a second recliner fitted over and coupled to an end of the rod.

[22] The second recliner may include: a second holder receiving therein a second operating cam, through a central portion of which a second shaft hole is formed, the second operating cam having a rod coupling part protruding from the second operating cam around the second shaft hole, the rod coupling part being coupled to the end of the rod, the second holder receiving therein a plurality of second lock gears around the second operating cam, with a plurality of second lock gear guide parts provided in the second holder to guide the second lock gears such that the second lock gears reciprocate depending on rotation of the second operating cam to conduct a locking or unlocking operation; and a second sector gear rotatably coupled to the second holder, with a second shaft passing hole formed through a central portion of the second sector gear, and second internal gear teeth formed along a circular rim of the second sector gear, the second internal gear teeth engaging with the second lock gears when the second lock gears conduct the locking operation.

[23] The rod coupling part may protrude a predetermined length such that an end thereof passes through the second holder, and the end of the rod may be inserted through the rod coupling part, wherein the end of the rod coupling part and the end of the rod may be welded to each other.

[24] The second recliner may include: a second holder receiving therein a second operating cam, through a central portion of which a second shaft hole is formed, the second operating cam having at least one second key slot in a circumferential inner surface of the second shaft hole, the second holder receiving therein a plurality of second lock gears around the second operating cam, with a plurality of second lock gear guide parts provided in the second holder to guide the second lock gears such that the second lock gears reciprocate depending on rotation of the second operating cam to conduct a locking or unlocking operation; a rod connection bushing inserted into the second shaft hole of the second operating cam through the second holder, with a second locking key provided on a circumferential outer surface of the rod connection bushing at a position corresponding to the second key slot such that the second locking key is inserted into the second key slot, and a rod coupling hole formed through the rod connection bushing from the first end to a second end thereof so that the rod is inserted into the rod connection bushing; and a second sector gear rotatably coupled to the second holder, with a second shaft passing hole formed through a central portion of the second sector gear, and second internal gear teeth formed along a circular rim of the second sector gear, the second internal gear teeth engaging with the second lock gears when the second lock gears conduct the locking operation.

[25] The rod may be inserted through the rod connection bushing such that the end of the rod protrudes from the second end of the rod connection bushing, and the end of the rod and the second end of the rod connection bushing may be welded to each other.

[26] Furthermore, a pair of compression pieces may extend from the second end of the rod connection bushing around the rod coupling hole, wherein the rod may be inserted through the rod connection bushing such that the end of the rod is disposed between the compression pieces, and the compression pieces and the rod may be compressed and held together and are thus fastened to each other.

[27] The second key slot may comprise three key slots formed around the first shaft hole at positions spaced apart from each other at regular angular intervals.

Advantageous Effects

[28] In the present invention, in a first recliner, because a gap is defined between a key slot of an operating cam and a locking key of a shaft such that the operating cam is slightly rotatable with respect to the shaft, a sector gear and a lock gear are prevented from skipping with each other. Therefore, there are advantages in that a safety hazard is prevented from being presented to an occupant, and the sector gear and the lock gear are prevented from being worn.

[29] Furthermore, when first recliners are coupled to the respective opposite ends of the shaft, because the gap is defined between the key slot of the operating cam and the locking key of the shaft, even if a tolerance in alignment between the first recliners exists within a predetermined range, the shaft can be coupled to the recliners, and torsional stress can prevented from being applied to the shaft.

[30] In addition, because a second recliner is fitted over and fixed to an end of a rod, which is connected to the first shaft coupled to the first recliner, the opposite recliners, which are integrally coupled to each other, can be stably operated, and an operation of coupling the recliners and the shaft to each other can be easily and reliably conducted. [31] As well, the present invention can reduce the proportion of defective products in the assembly process and reduce the manufacturing time, thus enhancing productivity. Brief Description of the Drawings

[32] Fig. 1 is a view showing the construction of a typical seat for vehicles;

[33] Fig. 2 is a side sectional view showing an example of a first recliner for vehicles according to a conventional technique; [34] Fig. 3 is an exploded perspective view of a first recliner, according to a first embodiment of the present invention;

[35] Fig. 4 is a perspective view showing a first operating cam of Fig. 3;

[36] Fig. 5 is a perspective view showing a shaft of Fig. 3;

[37] Figs. 6 and 7 are front views illustrating the operation of the first recliner according to the first embodiment of the present invention; [38] Fig. 8 is a perspective view showing first recliners provided on respective opposite ends of the shaft according to the first embodiment of the present invention; [39] Fig. 9 is a perspective view showing the coupling between the first shaft and a rod according to the first embodiment of the present invention; [40] Fig. 10 is a perspective view illustrating the assembly structure between the first recliner and a second recliner, according to the first embodiment of the present invention;

[41] Fig. 11 is an exploded perspective view of the second recliner of Fig. 10;

[42] Fig. 12 is a perspective view of a second operating cam of Fig. 11 ;

[43] Figs. 13 and 14 are side sectional view of the second recliner of Fig. 10;

[44] Fig. 15 is a perspective view illustrating the assembly structure between a first recliner and a second recliner, according to a second embodiment of the present invention;

[45] Fig. 16 is an exploded perspective view of the second recliner of Fig. 15;

[46] Fig. 17 is a perspective view of a second operating cam of Fig. 16;

[47] Figs. 18 and 19 are perspective views showing a rod connection bushing of Fig. 16;

[48] Figs. 20 and 21 are side sectional views of the second recliner of Fig. 15;

[49] Fig. 22 is a perspective view illustrating the assembly structure between a first recliner and a second recliner, according to a third embodiment of the present invention;

[50] Fig. 23 is an exploded perspective view of the second recliner of Fig. 22;

[51] Fig. 24 is a perspective view of an operating cam of Fig. 23;

[52] Figs. 25 and 26 are perspective views showing a rod connection bushing of Fig. 23; and [53] Figs. 27 and 28 are side sectional views of the second recliner of Fig. 22. Best Mode for Carrying Out the Invention

[54] <First embodiment; first recliner>

[55] First, a first recliner according to a first embodiment of the present invention will be described herein below with reference to Figs. 3 through 8.

[56] As shown in Fig. 3, the first recliner 100 according to the first embodiment includes a first shaft 110, a first sector gear 120, a first holder 130, a first operating cam 140, first lock gears 150, a first return spring 160 and a first housing 170, and serves to make it possible for a seat back of a vehicle seat to conduct a reclining motion. Hereinafter, in the description of the first recliner 100, the term "first" will be omitted at the beginning of the word designating each component, other than the term "first recliner 100".

[57] The first recliner 100 comprises the sector gear 120, along the circular rim of which internal gear teeth (122 of Fig. 6, formed on the surface opposite the surface seen in Fig. 3) are formed such that they engage with external gear teeth 151 of the lock gears 150, and which receives therein the lock gears 150 and the operating cam 140. The first recliner 100 further comprises the holder 130, which has three lock gear guide parts 132 that support the lock gears 150 such that the lock gears 150 maintain a movable state or a locked state, and the return spring 160, which provides elastic force for maintaining the locked state to the operating cam 140.

[58] In detail, the sector gear 120 has a circular shaft passing hole 121, through which the shaft 110 is inserted, the circular internal gear teeth (122 of Fig. 6), which engage with the external gear teeth 151 of the lock gears 150, and a seat back connection part 123, which is fastened to the seat back through several connection protrusions 123a that are provided on the seat back connection part 123 at positions spaced apart from each other by regular angular intervals on a concentric circle. The sector gear 120 receives the lock gears 150 and the operating cam 140 therein.

[59] The holder 130 is coupled to the sector gear 120 and includes a cam seating part

131, in which the central portion of the operating cam 140 is seated, and the lock gear guide parts 132, which support the three lock gears 150 such that the lock gears 150 can be smoothly moved to conduct the locking or unlocking movement. The holder 130 further includes a seat cushion connection part (provided on the surface opposite the surface seen in Fig. 4), which is fastened to the seat cushion through several connection protrusions that have shapes similar to that of the connection protrusions 123a of the sector gear 120, and lock gear seating parts 133, into which the respective lock gears 150 are seated.

[60] The operating cam 140 is provided in the sector gear 120 and the holder 130. In detail, the operating cam 140 has a shaft hole 143 in a central portion thereof and is fitted, through the shaft hole 143, over the shaft 110, which is inserted through the through hole 134 of the holder 130, such that the operating cam 140 is rotated along with the shaft 110. Furthermore, three protrusions 141 are provided on the circumferential outer edge of the operating cam 140.

[61] When the operating cam 140 is rotated, the three lock gears 150 are pushed by the three respective protrusions 141, which are provided on the circumferential outer edge of the operating cam 140, and thus slide in a state of being in contact with the lock gear guide parts 132 of the holder 130. Thereby, the external gear teeth 151 of the lock gears 150 enter a state of engaging with or being disengaged from the internal gear teeth (122 of Fig. 6) of the sector gear 120, so that the lock gears 150 are locked to or unlocked from the holder 130.

[62] The return spring 160 is a spring having a coil shape. An outer locking end 162 of the return spring 160 is locked to a stop protrusion 132a, which is provided on one lock gear guide part 132 of the holder 130, and an inner locking end 161 of the return spring 160 is inserted into and locked to one of locking slots 142a, which are formed in a connection boss 142 of the operating cam 140. Thus, the return spring 160 provides elastic force to the operating cam 140 such that the lock gears 150 and the sector gear 120 maintain a state of being engaged with each other in the locked state.

[63] The housing 170 serves to holds the sector gear 120 and the holder 130 such that the sector gear 120 and the holder 130 are prevented from being undesirably separated from each other.

[64] Meanwhile, as shown in Fig. 4, three key slots 145 are formed in the shaft hole 143 of the operating cam 140. As shown in Fig. 5, locking keys 112 are integrally provided on the shaft 110, which is inserted into the shaft hole 143 of the operating cam 140, at positions corresponding to the respective key slots 145, so that the locking keys 112 of the shaft 110 engage with the respective key slots 145 of the operating cam 140.

[65] As such, because the locking keys 112 of the shaft 110 engage with the key slots

145 of the operating cam 140, when the shaft 110 is rotated, the operating cam 140 is rotated along with the shaft 110. Then, the three protrusions 141, which are provided on the circumferential outer edge of the operating cam 140, push the corresponding lock gears 150 to slide them. Thereby, the external gear teeth 151 of the lock gears 150 are locked to or disengaged from the internal gear teeth (122 of Fig. 6) of the sector gear 120.

[66] Here, a gap is defined between each key slot 145 and the corresponding locking key

112 such that the operating cam 140 is slightly rotated with respect to the shaft 110.

[67] In detail, as shown in Fig. 6, the key slots 145 of the operating cam 140 and the locking keys 112 of the shaft 110 are formed such that the width (a) of each key slot 145 is greater than the width (b) of the corresponding locking key 112, so that the gap (G) is defined between each key slot 145 and the corresponding locking key 112 such that the operating cam 140 is slightly rotated with respect to the shaft 110.

[68] In this structure, after the inclination of the seat back has been adjusted, when an operating lever (not shown) is released so that the operating cam 140 is rotated in the direction in which the external gear teeth 151 of the lock gears 150 are locked to the internal gear teeth (122 of Fig. 6) of the sector gear 120, by the elastic force of the return spring 160, the operating cam 140 can be momentarily rapidly rotated regardless of the inertia force of the shaft 110, a connection rod (not shown), and the operating lever (not shown), thanks to the gaps defined between the key slots 145 of the operating cam 140 and the locking keys 112 of the shaft 110.

[69] As described above, because the operating cam 140, which is rapidly rotated, momentarily strikes and rotates the shaft 110 in a state in which they are in contact with each other, the speed at which the shaft 110 is rotated is increased, and the three lock gears 150 can also be rapidly moved by the pushing force of the three protrusions 141 provided on the circumferential outer edge of the operating cam 140. Therefore, the external gear teeth 151 of the lock gears 150 can be rapidly locked to the internal gear teeth of the sector gear, thus preventing skipping.

[70] Fig. 8 is a perspective view showing the first recliners provided on respective opposite ends of the shaft. As shown in Fig. 8, the opposite first recliners may be coupled to each other using a shaft 110' having a polygonal cross-section, that is, using the shaft 110', on the circumferential outer surface of which locking keys 112' extend in a longitudinal direction, without a separate connection rod (40 of Fig. 1). In this case, although a tolerance exists within a predetermined range of alignment between opposite first recliners, because the first recliners 100 are coupled to each other through the single shaft 110', there is an advantage in that torsion stress is prevented from being applied to the shaft.

[71] Meanwhile, from the results of many tests, it is preferable that the angle (α°) at which the operating cam 140 rotates relative to the shaft 110 due to the gap between the operating cam and the shaft range from 2° to 10°.

[72] In the case where the angle (α°) at which the operating cam 140 rotates relative to the shaft 110 due to the gap is too small, the force with which the operating cam 140 is momentarily rapidly rotated is insufficient, and thus it is difficult to rapidly rotate the shaft 110 and to rapidly slide the lock gears 150. In contrast, in the case where the angle is too large, the angle at which the shaft 110 is rotated to operate the operating cam 140 becomes too large, and the degree of rotation of the shaft 110 with respect to the operating cam 140 becomes too high.

[73] As such, it is preferable that the angle (α°) at which the operating cam 140 rotates relative to the shaft 110 due to the gap range from 2° to 10°. However, in the present invention, the angle (α°) is not limited to a range from 2° to 10°. As necessary, the angle (α°) may variously vary under the technical spirit in which a gap exists between the operating cam 140 and the shaft 110.

[74] <First embodiment; second recliner>

[75] Next, a second recliner 200 according to the first embodiment of the present invention will be described herein below with reference to Figs. 9 through 14.

[76] As shown in Fig. 10, a rod 1000 is coupled to one end of the first shaft 110, which is coupled to the first recliner 100 of the first embodiment, such that the central axis of the rod 1000 is aligned with that of the first shaft 110. An end of the rod 1000 is fitted into the second recliner 200.

[77] In detail, as shown in Fig. 9, a coupling part 114, which extends from the end of the first shaft 110, is fitted into a first end of the rod 1000. The second end of the rod 1000 is fitted through the second recliner 200. Here, an internal spline part is formed on the inner surface of the part of the rod 1000 into which the coupling part 114 of the first shaft 110 is fitted, such that the first shaft 110 is reliably coupled to the rod 1000 and is prevented from being rotated relative to the rod 1000.

[78] As shown in Fig. 11, the second recliner 200 according to the first embodiment includes a second sector gear 220, a second holder 230, a second operating cam 240, second lock gears 250, a second return spring 260 and a second housing 270. The second recliner 200 is operated along with the first recliner 100 such that the seat back of the vehicle seat can conduct the reclining motion.

[79] Other than the first operating cam 140 of the first recliner 100, the general construction of the second recliner 200 according to the first embodiment is the same as the first recliner 100, therefore only the operating cam 240 and the coupling between the operating cam 240 and the rod 1000 will be explained herein below.

[80] Hereinafter, in the description of the second recliner 200, the term "second" will be omitted at the beginning of the word designating each component, other than the term "second recliner 200".

[81] The operating cam 240 is installed in the sector gear 220 and the holder 230. A shaft hole 243 is formed at the center through the operating cam 240. A rod coupling part 242 for coupling with the second end of the rod 1000 is integrally provided around the shaft hole 243 on the operating cam 240.

[82] That is, as shown in Fig. 12, the cylindrical rod coupling part 242 integrally extends upwards from the upper surface of the operating cam 240. The shaft hole 243 is formed along the central axis of the rod coupling part 242.

[83] Meanwhile, three protrusions 241 are provided on the circumferential outer edge of the operating cam 240. When the operating cam 240 is rotated, the three lock gears 250 are pushed by the three respective protrusions 241, which are provided on the circum- ferential outer edge of the operating cam 240, and thus slide in a state of contact with lock gear guide parts 232 of the holder 230. Thereby, external gear teeth 251 of the lock gears 250 enter a state of engaging with or being disengaged from internal gear teeth 222 of the sector gear 220, so that the lock gears 250 are locked to or unlocked from the holder 230.

[84] At this time, the locking or unlocking operation of the second recliner 200 is conducted in conjunction with the locking or unlocking operation of the first recliner 100. In other words, when the first recliner 100 conducts the locking operation, the second recliner 200 also conducts the locking operation. When the first recliner 100 conducts the unlocking operation, the second recliner 200 also conducts the unlocking operation.

[85] The coupling between the operating cam 240 and the rod 1000 will be explained herein below with reference to Figs. 13 and 14.

[86] After the first recliner 100 has been coupled to the first shaft 110, the coupling part

114 of the first shaft 110 is inserted into the first end of the rod 1000. Thereafter, as shown in Fig. 13, the second end of the rod 1000 is inserted through the operating cam 240 of the second recliner 200. Here, the second end of the rod 1000 is inserted through the rod coupling part 242 of the operating cam 240 such that it protrudes a predetermined length outside the rod coupling part 242. The end surface of the rod coupling part 242 and the circumferential outer surface of the part of the rod 1000 which protrudes outside the rod coupling part 242 are fixed to each other by welding (W).

[87] That is, the first recliner 100 is installed in one end of the seat. The first shaft 110 is coupled to the first recliner 100. The first end of the rod 1000 is coupled to the first shaft 110, which is coupled to the first recliner 100 (alternatively, the first shaft 110 may be coupled to the first recliner 100 after the first shaft 110 and the rod 1000 are first coupled to each other). Thereafter, the second recliner 200 is installed in the other end of the seat such that the second end of the rod 1000 is inserted through the operating cam 240 of the second recliner 200. As such, in the state in which the first and second recliners 100 and 200 are installed in the seat, the second end of the rod 1000 is coupled to the second recliner 200 by welding (W).

[88] As described above, the recliner assembly including the first recliner 100, the first shaft 110, the rod 1000 and the second recliner 200 can solves problems experienced in the conventional art, in which the recliners 10 and 10' are installed in opposite ends of the seat cushion, the shafts 14 and 14' are coupled to the respective recliners 10 and 10', and, thereafter, the first shaft 14 is first attached to the rod 40 by welding, and the second shaft 14' is subsequently attached to the rod 40 by welding, that is, the problems of an increase in manufacturing time, a reduction in productivity, and an increase in the proportion of defective products.

[89] <Second embodiment; second recliner>

[90] Hereinafter, a second recliner 300 according to a second embodiment of the present invention will be described with reference to Figs. 15 through 21.

[91] As shown in Fig. 15, a rod 1000 is coupled to one end of a first shaft 110, which is coupled to a first recliner 100, such that the central axis of the rod 1000 is aligned with that of the first shaft 110. An end of the rod 1000 is inserted into and coupled to the second recliner 300.

[92] In detail, a coupling part 114, which extends from the end of the first shaft 110, is fitted into the first end of the rod 1000. The second end of the rod 1000 is inserted through the second recliner 300.

[93] As shown in Fig. 16, the second recliner 300 according to the second embodiment includes a second sector gear 320, a second holder 330, a second operating cam 340, second lock gears 350, a second return spring 360, a second housing 370 and a rod connection bushing 380. The second recliner 300 is operated in conjunction with the first recliner 100 such that the seat back of the vehicle seat can conduct the reclining motion.

[94] Meanwhile, the first recliner 100 according to the second embodiment is the same as the first recliner 100 of the first embodiment. Furthermore, in the construction of the second recliner 300 of the second embodiment, the general construction of the second recliner 300, other than the operating cam 340 and the rod connection bushing 380, remains the same as the second recliner 200 of the first embodiment, therefore only the operating cam 340, the rod connection bushing 380 and the coupling between them and the rod 1000 will be explained herein below.

[95] Hereinafter, in the description of the second recliner 300, the term "second" will be omitted at the beginning of the word designating each component, other than the term "second recliner 300".

[96] As shown in Fig. 17, the operating cam 340 is installed in the sector gear 320 and the holder 330. A shaft hole 343 is formed at the center through the operating cam 340. Furthermore, at least one second key slot 345 is formed in the circumferential inner surface of the shaft hole 343.

[97] Meanwhile, three protrusions 341 are provided on the circumferential outer edge of the operating cam 340. When the operating cam 340 is rotated, the three lock gears 350 are pushed by the three respective protrusions 341, which are provided on the circumferential outer edge of the operating cam 340, and thus slide in a state of being in contact with lock gear guide parts 332 of the holder 330. Thereby, external gear teeth 351 of the lock gears 350 enter a state of engaging with or being disengaged from internal gear teeth 322 of the sector gear 320, so that the lock gears 350 are locked to or unlocked from the holder 330.

[98] At this time, the locking or unlocking operation of the second recliner 300 is conducted in conjunction with the locking or unlocking operation of the first recliner 100. In other words, when the first recliner 100 conducts the locking operation, the second recliner 300 also conducts the locking operation. When the first recliner 100 conducts the unlocking operation, the second recliner 300 also conducts the unlocking operation.

[99] To provide the rotating force to the operating cam 340, as shown in Figs. 18 and 19, the rod connection bushing 380 is coupled to the operating cam 340. Here, the first end of the rod connection bushing 380 is inserted into the shaft hole 343 of the operating cam 340 through the holder 330. Locking keys 384 are provided on the circumferential outer surface of the rod connection bushing 380 at positions corresponding to the respective key slots 345 formed in the shaft hole 343 of the operating cam 340, so that the locking keys 384 are inserted into the respective key slots 345 of the operating cam 340. A rod coupling hole 382 is formed through opposite ends of the rod connection bushing 380.

[100] In detail, the rod connection bushing 380 has a cylindrical shape. The rod coupling hole 382 is formed through the first and second ends of the rod connection bushing 380, and an extension part 383 extends a predetermined length from the first end of the rod connection bushing 380 around the rod connection hole 382. The locking keys 384, which engage with the respective key slots 345 of the operating cam 340, protrude from the extension part 383 outwards in radial directions at positions corresponding to the respective key slots 345.

[101] The operating cam 340, the rod connection bushing 380 and the coupling between them and the rod 1000 will be explained herein below with reference to Figs. 20 and 21.

[102] After the first recliner 100 has been coupled to the first shaft 110, the coupling part

114 of the first shaft 110 is inserted into the first end of the rod 1000. Thereafter, as shown in Fig. 20, the second end of the rod 1000 is inserted through the operating cam 340 of the second recliner 300.

[103] Subsequently, the first end of the rod connection bushing 380 is inserted into the holder 330 such that it corresponds to the key slots 345 of the operating cam 340, that is, such that the locking keys 384, which protrude from the extension part 383 of the first end of the rod connection bushing 380, engage with the respective key slots 345 formed in the circumferential inner surface of the shaft hole 343 of the operating cam 340. The second end of the rod connection bushing 380 extends outside the holder 330.

[104] In the state in which the locking keys 384 of the rod connection bushing 380 engage with the respective key slots 345 of the operating cam 340, the shaft hole 343 of the operating cam 340 is precisely aligned with the rod coupling hole 382 of the rod connection bushing 380 along the same line. Thereafter, the second end of the rod 1000 is inserted into the shaft hole 343 of the operating cam 340 and the rod coupling hole 382 of the rod connection bushing 380, which are aligned with each other along the same line, such that part of the second end of the rod 1000 protrudes outside the second end of the rod connection bushing 380. Subsequently, as shown in Fig. 21, the end surface of the rod connection bushing 380 and the circumferential outer surface of the part of the rod 1000 that protrudes outside the rod connection bushing 380 are integrated with each other by welding (W).

[105] That is, the first recliner 100 is installed in one end of the seat. The first shaft 110 is coupled to the first recliner 100. The first end of the rod 1000 is coupled to the first shaft 110 coupled to the first recliner 100 (alternatively, the first shaft 110 may be coupled to the first recliner 100, after the first shaft 110 and the rod 1000 are first coupled to each other). Thereafter, the second recliner 300 is installed in the other end of the seat such that the second end of the rod 1000 is fitted through the operating cam 340 of the second recliner 300. As such, in the state in which the first and second recliners 100 and 300 are installed in the seat, the second end of the rod 1000 is fixed to the second recliner 300.

[106] Meanwhile, a gap is defined between each key slot 345 and the corresponding locking key 384 such that the operating cam 340 is rotatable with respect to the rod connection bushing 380. The reason for the formation of the gaps between the operating cam 340 and the rod connection bushing 380 and the structure thereof is the same as that of the technique of the first embodiment, in which the gaps are defined between the first key slots 145 of the first operating cam 140 of the first recliner 100 and the first locking keys 112 of the first shaft 110, therefore further explanation is deemed unnecessary.

[107] As described above, the recliner assembly including the first recliner 100, the first shaft 110, the rod 1000 and the second recliner 300 can solve problems experienced with the conventional art, in which the recliners 10 and 10' are installed in opposite ends of the seat cushion, the shafts 14 and 14' are coupled to the respective recliners 10 and 10', and, thereafter, the first shaft 14 is first attached to the rod 40 by welding, and the second shaft 14' is subsequently attached to the rod 40 by welding, that is, the problems of an increase in manufacturing time, a reduction in productivity, and an increase in the proportion of defective products.

[108] <Third embodiment; second recliner>

[109] Hereinafter, a second recliner 400 according to a third embodiment of the present invention will be described with reference to Figs. 22 through 28.

[110] As shown in Fig. 22, a rod 1000 is coupled to one end of a first shaft 110, which is coupled to a first recliner 100, such that the central axis of the rod 1000 is aligned with that of the first shaft 110. An end of the rod 1000 is inserted into and coupled to the second recliner 400.

[I l l] In detail, a coupling part 114, which extends from the end of the first shaft 110, is fitted into the first end of the rod 1000. The second end of the rod 1000 is fitted through the second recliner 400.

[112] As shown in Fig. 23, the second recliner 400 according to the third embodiment includes a second sector gear 420, a second holder 430, a second operating cam 440, second lock gears 450, a second return spring 460, a second housing 470 and a rod connection bushing 480. The second recliner 400 is operated in conjunction with the first recliner 100 such that the seat back of the vehicle seat can conduct the reclining motion.

[113] Meanwhile, the first recliner 100 according to the third embodiment is the same as the first recliner 100 of the first embodiment. Furthermore, in the construction of the second recliner 400 of the third embodiment, the general construction of the second recliner 400, other than the operating cam 440 and the rod connection bushing 480, remains the same as the second recliner 200 of the first embodiment, therefore only the operating cam 440, the rod connection bushing 480 and the coupling between them and the rod 1000 will be explained herein below.

[114] Hereinafter, in the description of the second recliner 400, the term "second" will be omitted at the beginning of the word designating each component, other than the term "second recliner 400".

[115] As shown in Fig. 24, the operating cam 440 is installed in the sector gear 420 and the holder 430. A shaft hole 443 is formed at the center through the operating cam 440. Furthermore, at least one key slot 445 is formed in the circumferential inner surface of the shaft hole 443.

[116] Meanwhile, three protrusions 441 are provided on the circumferential outer edge of the operating cam 440. When the operating cam 440 is rotated, the three lock gears 450 are pushed by the three respective protrusions 441, which are provided on the circumferential outer edge of the operating cam 440, and thus slide in a state of being in contact with lock gear guide parts 432 of the holder 430. Thereby, the external gear teeth 451 of the lock gears 450 enter a state of being engaged with or disengaged from internal gear teeth 422 of the sector gear 420, so that the lock gears 450 are locked to or unlocked from the holder 430.

[117] At this time, the locking or unlocking operation of the second recliner 400 is conducted in conjunction with the locking or unlocking operation of the first recliner 100. In other words, when the first recliner 100 conducts the locking operation, the second recliner 400 also conducts the locking operation. When the first recliner 100 conducts the unlocking operation, the second recliner 400 also conducts the unlocking operation.

[118] To provide the rotating force to the operating cam 440, as shown in Figs. 25 and 26, the rod connection bushing 480 is coupled to the operating cam 440. Here, the first end of the rod connection bushing 480 is inserted into the shaft hole 443 of the operating cam 440 through the holder 430. Locking keys 484 are provided on the circumferential outer surface of the rod connection bushing 480 at positions corresponding to the re spective key slots 445 formed in the shaft hole 443 of the operating cam 440, so that the locking keys 484 are inserted into the respective key slots 445 of the operating cam 440. A rod coupling hole 482 is formed through opposite ends of the rod connection bushing 480.

[119] In detail, the rod connection bushing 480 has a cylindrical shape. The rod coupling hole 482 is formed through the first and second ends of the rod connection bushing 480, and an extension part 483 extends a predetermined length from the first end of the rod connection bushing 480 around the rod connection hole 482. The locking keys 484, which engage with the respective key slots 445 of the operating cam 440, protrude from the extension part 483 outwards in radial directions at positions corresponding to the respective key slots 445. Furthermore, a pair of compression pieces 486, each of which protrudes a predetermined length, is provided on the second end of the rod connection bushing 480 around the rod coupling hole 482.

[120] The operating cam 440, the rod connection bushing 480 and the coupling between them and the rod 1000 will be explained herein below with reference to Figs. 27 and 28.

[121] After the first recliner 100 has been coupled to the first shaft 110, the coupling part

114 of the first shaft 110 is inserted into the first end of the rod 1000. Thereafter, as shown in Fig. 27, the second end of the rod 1000 is inserted through the operating cam 440 of the second recliner 400.

[122] Subsequently, the first end of the rod connection bushing 480 is inserted into the holder 430 such that it corresponds to the key slots 445 of the operating cam 440, that is, such that the locking keys 484, which protrude from the extension part 483 of the first end of the rod connection bushing 480, engage with the respective key slots 445 formed in the circumferential inner surface of the shaft hole 443 of the operating cam 440. The second end of the rod connection bushing 480 protrudes outside the holder 430.

[123] In the state in which the locking keys 484 of the rod connection bushing 480 engage with the respective key slots 445 of the operating cam 440, the shaft hole 443 of the operating cam 440 is precisely aligned with the rod coupling hole 482 of the rod connection bushing 480 along the same line. Thereafter, the second end of the rod 1000 is inserted into the shaft hole 443 of the operating cam 440 and the rod coupling hole 482 of the rod connection bushing 480, which are aligned with each other along the same line, such that part of the second end of the rod 1000 protrudes outside the second end of the rod connection bushing 480, in detail, such that the part of the second end of the rod 1000 is disposed between the two compression pieces 486 provided on the second end of the rod connection bushing 480.

[124] As such, after the operating cam 440, the rod connection bushing 480 and the rod

1000 have been coupled to each other, the two compression pieces 486 of the rod connection bushing 480 and the second end of the rod 1000 are compressed inwards together so that they are firmly fixed to each other.

[125] That is, the first recliner 100 is installed in one end of the seat. The first shaft 110 is coupled to the first recliner 100. The first end of the rod 1000 is coupled to the first shaft 110 coupled to the first recliner 100 (alternatively, the first shaft 110 may be coupled to the first recliner 100, after the first shaft 110 and the rod 1000 are first coupled to each other). Thereafter, the second recliner 400 is installed in the other end of the seat such that the second end of the rod 1000 is inserted through the operating cam 440 of the second recliner 400. As such, in the state in which the first and second recliners 100 and 400 are installed in the seat, the second end of the rod 1000 is fixed to the second recliner 400 by welding (W).

[126] Meanwhile, a gap is defined between each key slot 445 and the corresponding locking key 484 such that the operating cam 440 is rotatable with respect to the rod connection bushing 480. The reason for the formation of the gaps between the operating cam 440 and the rod connection bushing 480 and the structure thereof are the same as those of the technique of the first embodiment, in which the gaps are defined between the first key slots 145 of the first operating cam 140 of the first recliner 100 and the first locking keys 112 of the first shaft 110, therefore further explanation is deemed unnecessary.

[127] As described above, the recliner assembly, including the first recliner 100, the first shaft 110, the rod 1000 and the second recliner 400 can solve problems experienced with the conventional art, in which the recliners 10 and 10' are installed in opposite ends of the seat cushion, the shafts 14 and 14' are coupled to the respective recliners 10 and 10', and, thereafter, the first shaft 14 is first attached to the rod 40 by welding, and the second shaft 14' is subsequently attached to the rod 40 by welding, that is, the problems of an increase in the manufacturing time, a reduction in the productivity, and an increase in the proportion of defective products.

Claims

[1] A recliner assembly, comprising: a first recliner, including: a first holder, receiving therein a first operating cam, through a central portion of which a first shaft hole is formed, the first holder receiving therein a plurality of first lock gears around the first operating cam, with a plurality of first lock gear guide parts provided in the first holder to guide the first lock gears such that the first lock gears reciprocate depending on rotation of the first operating cam to conduct a locking or unlocking operation; and a first sector gear rotatably coupled to the first holder, with a first shaft passing hole formed through a central portion of the first sector gear, and first internal gear teeth formed along a circular rim of the first sector gear, the first internal gear teeth engaging with the first lock gears when the first lock gears conduct the locking operation; and a shaft coupled to the first operating cam to provide a rotating force thereto, wherein at least one first key slot is formed in a circumferential inner surface of the first shaft hole of the first operating cam, a first locking key is integrally provided on the shaft at a position corresponding to the first key slot so that the first locking key engages with the first key slot, and a gap is defined between the first key slot and the first locking key such that the first operating cam is rotatable with respect to the shaft.

[2] The recliner assembly according to claim 1, wherein the first key slot comprises three first key slots formed around the first shaft hole at positions spaced apart from each other at regular angular intervals.

[3] The recliner assembly according to claim 1, further comprising: a rod coupled to one end of the shaft such that a central axis of the rod is aligned with a central axis of the shaft; and a second recliner fitted over and coupled to an end of the rod.

[4] The recliner assembly according to claim 3, wherein the second recliner comprises: a second holder receiving therein a second operating cam, through a central portion of which a second shaft hole is formed, the second operating cam having a rod coupling part protruding from the second operating cam around the second shaft hole, the rod coupling part being coupled to the end of the rod, the second holder receiving therein a plurality of second lock gears around the second operating cam, with a plurality of second lock gear guide parts provided in the second holder to guide the second lock gears such that the second lock gears re- ciprocate depending on rotation of the second operating cam to conduct a locking or unlocking operation; and a second sector gear rotatably coupled to the second holder, with a second shaft passing hole formed through a central portion of the second sector gear, and second internal gear teeth formed along a circular rim of the second sector gear, the second internal gear teeth engaging with the second lock gears when the second lock gears conduct the locking operation.

[5] The recliner assembly according to claim 4, wherein the rod coupling part protrudes a predetermined length such that an end thereof passes through the second holder, and the end of the rod is inserted through the rod coupling part, wherein the end of the rod coupling part and the end of the rod are welded to each other.

[6] The recliner assembly according to claim 3, wherein the second recliner comprises: a second holder receiving therein a second operating cam, through a central portion of which a second shaft hole is formed, the second operating cam having at least one second key slot in a circumferential inner surface of the second shaft hole, the second holder receiving therein a plurality of second lock gears around the second operating cam, with a plurality of second lock gear guide parts provided in the second holder to guide the second lock gears such that the second lock gears reciprocate depending on rotation of the second operating cam to conduct a locking or unlocking operation; a rod connection bushing inserted into the second shaft hole of the second operating cam through the second holder, with a second locking key provided on a circumferential outer surface of the rod connection bushing at a position corresponding to the second key slot such that the second locking key is inserted into the second key slot, and a rod coupling hole formed through the rod connection bushing from the first end to a second end thereof so that the rod is inserted into the rod connection bushing; and a second sector gear rotatably coupled to the second holder, with a second shaft passing hole formed through a central portion of the second sector gear, and second internal gear teeth formed along a circular rim of the second sector gear, the second internal gear teeth engaging with the second lock gears when the second lock gears conduct the locking operation.

[7] The recliner assembly according to claim 6, wherein the rod is inserted through the rod connection bushing such that the end of the rod protrudes from the second end of the rod connection bushing, and the end of the rod and the second end of the rod connection bushing are welded to each other.

[8] The recliner assembly according to claim 6, wherein a pair of compression pieces extends from the second end of the rod connection bushing around the rod coupling hole, wherein the rod is inserted through the rod connection bushing such that the end of the rod is disposed between the compression pieces, and the compression pieces and the rod are compressed and held together and are thus fastened to each other.

[9] The recliner assembly according to any one of claims 6 through 8, wherein the second key slot comprises three key slots formed around the first shaft hole at positions spaced apart from each other at regular angular intervals.