JP2009226111A - Locking mechanism and seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a locking mechanism suppressing variations in an engagement force (a locking force) with an engagement part engaged with an engagement object part (a locked state) to a necessary minimum under a state of satisfying the specifications, reducing the variation in an operation force (an unlocking operation force) when disengaging the engagement part from the engagement object part, and requiring a small operation force when disengaging the engagement part from the engagement object part, and to provide a seat having the lock. <P>SOLUTION: An upper-part locking mechanism 59 is provided with a spring 211 that engages/disengages with respect to the engagement object part, energizes a lever 201 rotating along with the engagement member to be locked/unlocked, and enlarging the energization force more as the engagement part separates farther from the engagement object part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a first member, a second member provided to be rotatable relative to the first member, and one of the first member and the second member. Provided on the other member of the first member and the second member, the engaging portion is detachable, and the first member and the second member are engaged when engaged. A locking mechanism comprising: an engaged portion that prohibits relative rotation with the member; and a first urging means that urges the engaging portion in a direction to engage the engaged portion, and The present invention relates to a seat having a lock mechanism.

  As a lock mechanism, there exists a thing of a structure as shown in FIGS. 13-15, for example. 13 is a partially cutaway view of a conventional locking mechanism, FIG. 14 is a cross-sectional view taken along a cutting line AA in FIG. 13, and FIG. 15 is a cross-sectional view taken along a cutting line BB in FIG. In these drawings, a ratchet 5 provided on the upper arm on the seat back side is rotatably attached to the base plate 1 provided on the lower arm on the seat cushion side via a hinge pin 3. Inner teeth 7 are formed on the ratchet 5 on a circumference around the hinge pin 3 that is the rotation center axis of the upper arm on a plane parallel to the rotation plane of the ratchet 5 (upper arm).

  Between the base plate 1 and the ratchet 5, a pole 11 having external teeth 9 that can mesh with the internal teeth 7 is disposed. On the base plate 1, the pole 11 is guided in a radial direction of a circle around the hinge pin 3 that is the rotation center axis of the upper arm on a plane parallel to the rotation plane of the ratchet 5 (upper arm). Guides 13 and 13 ′ for engaging / separating 9 with the internal teeth 7 are formed.

  Further, a cam 15 is attached to the hinge pin 3 so as to rotate integrally with the hinge pin by pushing the back portion of the pole 11 and meshing the outer teeth 9 of the pole 11 with the inner teeth 7 of the ratchet 5. Further, the cam 15 is engaged with the outer end of a spiral spring 17 whose inner end is locked to the base plate 1, and the cam 15 is in a direction in which the outer teeth 9 of the pole 11 mesh with the inner teeth 7 of the ratchet 5. It is biased in the (locking direction).

  The disc-shaped release plate 21 having a hole through which the hinge pin 3 is inserted is arranged so as to be laminated with the cam 15, the pole 11, and the guides 13 and 13 'in the axial direction of the hinge pin 3. On the other hand, the cam 15 is formed with a protrusion 15a that can be fitted into the hole 21a of the release plate 21, so that the release plate 21 and the cam 15 rotate together.

  A convex portion 11 a that engages with a cam groove 21 b formed in the release plate 21 is formed on a surface parallel to the rotation plane of the ratchet 5 (upper arm) of the pole 11. The shape of the cam groove 21b is set to a shape that causes the external teeth 9 of the pole 11 to move away from the internal teeth 7 of the ratchet 5 when the release plate 21 rotates counterclockwise in FIG. .

The operation of the above configuration will be described.
Normally, the outer teeth 9 of the pole 11 provided on the base plate 1 side mesh with the inner teeth 7 of the ratchet (upper arm) 5 by the urging force of the spiral spring 17, and the upper arm is prohibited from rotating with respect to the lower arm. Become.

In FIG. 13, when the hinge pin 3 and the cam 15 that rotates together with the hinge pin 3 are rotated such that the release plate 21 rotates counterclockwise against the urging force of the spiral spring 17. When the pole 11 moves in a direction in which the outer teeth 9 are separated from the inner teeth 7 of the ratchet 5 and the meshing between the outer teeth 9 and the inner teeth 7 is released, the upper arm is unlocked so that the upper arm can rotate with respect to the lower arm. (For example, refer to Patent Document 1).
JP 2006-122443 A (FIGS. 7 to 9)

  In the lock mechanism configured as described above, when the hinge pin 3 is rotated from the locked state to the unlocked state, the amount of deformation of the spiral spring 17 gradually increases according to the amount of rotation of the hinge pin 3, so that the urging force also gradually increases. . Therefore, there is a problem that the unlocking operation force gradually increases, the unlocking operation force varies, and the operability is poor.

  Furthermore, as shown in FIG. 14, when the hinge pin 3 is rotated using the lever 25 attached to the hinge pin 3, if the lever length (L) of the lever 25 cannot be secured sufficiently, the operating force is large and the operability is poor. There is a problem.

  The present invention has been made in view of the above problems, and the problem is that the engagement force (lock force) in a state where the engagement portion is engaged with the engaged portion (lock state) satisfies the specifications. The fluctuation of the operating force (unlocking operation force) when the engaging part is released from the engaged part is small and the engaging part is released from the engaged part. An object of the present invention is to provide a lock mechanism and a seat having a small operating force.

  The invention according to claim 1 is provided on one of the first member, the second member rotatably provided on the first member, the first member, and the second member. The engagement member, the first member, and the second member are provided on the other member of the second member, the engagement member is detachable, and the first member of the second member is engaged when engaged. An engaged portion that prohibits rotation with respect to the unit, a unit that includes a first urging means that urges the engaging portion in a direction in which the engaging portion engages with the engaged portion, and an urging force of the urging means. And a lock release means for releasing the engagement portion from the engaged portion, wherein the lock release means is a lever rotatably provided on the unit, and the engagement portion Urges the lever in a direction to disengage from the engaged portion, and the engaging portion disengages from the engaged portion. A locking mechanism, characterized in that Complimentary wireless Internet access as the biasing force provided second biasing means increases.

  Usually, the engaging portion is engaged with the engaged portion by the urging force of the first urging means, and the rotation of the second member relative to the first member is prohibited. Here, when the engaging portion is separated from the engaged portion against the urging force of the first urging means, rotation of the second member relative to the first member is permitted.

  In the invention according to claim 2, one end of the second urging means is locked to either the first member side or the second member side, and the other end is the The lock mechanism according to claim 1, wherein the lock mechanism is a tension spring locked to the lever.

  According to a third aspect of the present invention, when the engagement portion is engaged with the engaged portion, the distance between the line of action of the force of the tension spring and the rotation center of the lever is short. The second biasing means and the lever are provided so that the distance between the line of action of the force of the tension spring and the center of rotation of the lever increases as the part moves away from the engaged part. The locking mechanism according to claim 2, wherein the locking mechanism is provided.

  The invention according to claim 4 is provided between the lower seat back provided rotatably with respect to the seat cushion, the upper seat back provided rotatably with the lower seat back, and the seat cushion and the lower seat back. And a lower lock mechanism that allows / inhibits rotation of the lower seat back and an upper lock mechanism that is provided between the lower seat back and the upper seat back and permits / inhibits rotation of the upper seat back. One of the lower locking mechanism and the upper locking mechanism is a locking mechanism according to any one of claims 1 to 3, wherein the locking mechanism is a seat.

  According to a fifth aspect of the present invention, the other lock mechanism of the lower lock mechanism and the upper lock mechanism has the unit according to any one of the first to third aspects, and the unit includes the lower lock mechanism. 5. The seat according to claim 4, wherein the upper locking mechanism is the same as a unit of one of the locking mechanisms.

  According to the invention of claim 1-5, the urging force of the first urging means gradually increases until the engaging portion is moved and the engaging portion is completely separated from the engaged portion. However, the urging force is increased as the engaging portion urges the operating lever in the direction in which the engaging portion is disengaged from the engaged portion and the engaging portion is disengaged from the engaged portion. By providing the urging means, the increase in the urging force of the first urging means is offset by the increase in the urging force of the second urging means, and the engaging portion is released from the engaged portion. Fluctuation in operating force is reduced.

  Further, the second urging means urges the operation lever in a direction in which the engaging portion is detached from the engaged portion, and the more the engaging portion is separated from the engaged portion, the more Energizing power increases. That is, the urging force of the second urging means when the engaging portion is engaged with the engaged portion is small. Therefore, the engaging force in a state where the engaging portion is engaged with the engaged portion can be kept to the minimum necessary variation while satisfying the specifications.

Furthermore, by appropriately setting the urging force of the second urging means, it is possible to reduce the operating force when the engaging portion is disengaged from the engaged portion.
According to the invention of claim 5, the other lock mechanism of the lower lock mechanism and the upper lock mechanism has the unit according to any one of claims 1 to 3, and the unit is Of the lower lock mechanism and the upper lock mechanism, the same unit as the unit of one of the lock mechanisms can be used so that parts can be shared.

  First, the seat provided with the lock mechanism of this embodiment will be described with reference to FIGS. 9 and 10. In FIG. 9, 51 and 61 are a front seat and a rear seat arranged in the front-rear direction. The seat back 53 of the front seat 51 is composed of a lower seat back 53a provided rotatably with respect to the seat cushion 55, and an upper seat back 53b provided rotatably on the lower seat back 53a.

  A lower lock mechanism 57 is provided between the seat cushion 55 and the lower seat back 53a to permit / inhibit rotation of the lower seat back 53a. Further, an upper lock mechanism 59 of this embodiment is provided between the lower seat back 53a and the upper seat back 53b, and permits / inhibits the rotation of the upper seat back 53b.

  The lower lock mechanism 57 includes a unit 56 that prohibits the rotation of the lower seat back 53a, and an operation lever 57a (lock release means) that allows the lower seat back 53a to rotate when operated.

  The upper lock mechanism 59 includes a unit 58 that prohibits rotation of the upper seat back 53b, and an operation lever 59a (lock release means) that allows operation to rotate the upper seat back 53b.

  In the seat with the above configuration, as shown in FIG. 10, when the upper seat back 53b is tilted forward by operating the operation lever 59a of the upper lock mechanism 59, the rear surface of the upper seat back 53b becomes substantially horizontal, and the rear seat It becomes a table for 61.

  Next, the internal structure of the side portion of the front seat 51 will be described with reference to FIGS. FIG. 1 is a side view of a seat back frame provided with a lock mechanism according to an embodiment, and FIG. 2 is a cross-sectional view taken along a cutting line AA in FIG.

  In these drawings, the side portion of the seat back frame 71 is positioned below the seat back 53, is provided rotatably with respect to the lower arm 73 that is the seat cushion side frame, and is a structural material of the lower seat back 53a. A first upper arm (first member) 75 and a second upper arm (second member) which is positioned above the seat back 53 and is rotatably provided to the first upper arm 75 and is a structural material of the upper seat back 53b. ) 77.

  The lower lock mechanism 57 described above is provided between the lower arm 73 and the first upper arm 75 to permit / inhibit the rotation of the first upper arm 75. Further, the above-described upper lock mechanism 59 is provided between the first upper arm 75 and the second upper arm 77 to permit / inhibit the rotation of the second upper arm 77.

  Here, the upper locking mechanism 59 will be described with reference to FIGS. 3 is an external view of the unit 58 of the upper locking mechanism 59, FIG. 4 is a cross-sectional view taken along the section line CC of FIG. 3, FIG. 5 is a rear view of FIG. 3, and FIG. 7 is a cross-sectional view taken along the line EE in FIG. 3, and FIG. 8 is a view with the release plate removed in FIG.

  In the present embodiment, the unit 56 of the lower lock mechanism 57 and the unit 58 of the upper lock mechanism 59 are the same, so the description of the unit 56 of the lower lock mechanism 57 is omitted.

  As shown in FIG. 4, in the unit 58 of the upper lock mechanism 59 of this embodiment, the base plate 100 is attached to the first upper arm 75 and the ratchet 130 is attached to the second upper arm 77.

  As shown in FIGS. 3 to 6, a ratchet holding portion 100 b bent in the rotation axis direction of the base plate 100 is formed on the outer peripheral portion of the disc-shaped base plate 100, and further, the outer peripheral portion of the base plate 100 and the ratchet The disc-shaped base plate 100 and the disc-shaped ratchet 130 are joined to each other so as to be rotatable relative to each other by an attachment fitting 206 provided on the outer periphery of the disc 130. The ratchet holding portion 100b prohibits movement of the base plate 100 and the ratchet 130 in a direction perpendicular to the rotation axis, and the mounting bracket 206 prohibits movement of the base plate 100 and the ratchet 130 in the rotation axis direction. A hole 101 and a hole 131 are formed in a portion through which the rotation center axis of the base plate 100 and the ratchet 130 passes, and a pin 120 is inserted through the hole 101 and the hole 131.

  As shown in FIGS. 4 and 6, a substantially circular recess 132 centering on the rotation center axis of the ratchet 130 is formed on the surface of the ratchet 130 facing the base plate 100. Internal teeth 133 are engraved.

  As shown in FIGS. 4 and 6, a recess 104 is formed on the surface of the base plate 100 facing the recess 132 of the ratchet 130, and as shown in FIG. Guide protrusions 105 and 106 are projected toward the bottom, and guide protrusions 107 and 108 are projected toward the ratchet 130 at the bottom of the bottom surface.

  On the surface of the base plate 100 opposite to the ratchet 130 side, a plurality of coupling protrusions 100a to be attached to the first upper arm 75 are equally spaced on the same circumference centered on the hole 101 (center of the base plate 100). It is arranged by. On the other hand, on the surface of the ratchet 130 opposite to the base plate 100 side, a plurality of coupling protrusions 130a for attachment to the second upper arm 77 are on the same circumference centering on the hole 131 (the tilting center of the ratchet 130). Are arranged at equal intervals.

  As shown in FIG. 7, the pole 140 is sandwiched between the guide surfaces 105a and 106a of the guide protrusions 105 and 106, and is slidably guided in a direction perpendicular to the rotation center axis of the ratchet 130. The coupling portion 141 is configured to be able to mesh with the internal teeth (engaged portion) 133 of the ratchet 130.

  Similarly, the pole 150 is sandwiched between the guide surfaces 107a and 108a of the guide protrusions 107 and 108, and is slidably guided in a direction orthogonal to the rotation center axis of the ratchet 130, and external teeth (engagement portions) 151 at the front end portion. Is configured to mesh with the internal teeth (engaged portion) 133 of the ratchet 130.

  A cross-sectional oval portion 123 is formed in the intermediate portion of the pin 120, and an oval hole 171 of the cam 170 is fitted in the cross-sectional oval portion 123. For this reason, the cam 170 is fitted to the pin 120 in a relatively non-rotatable state.

  The cam 170 rotates together with the pin 120, and as shown in FIG. 8, three pressing portions 174a, 174b, 174c, 175a, 175b, and 175c are formed at the upper portion and three portions at the lower portion. Of the three pressing portions, the back portions 142 and 152 of the poles 140 and 150 are pushed in the direction of the external teeth 141 and 151 with the central pressing portions 174b and 175b, and the external teeth 141 and 151 of the poles 140 and 150 are ratchet. It meshes with 130 internal teeth 133. The remaining pressing portions 174a and 175a and the pressing portions 174c and 175c are set so as to come into contact when the poles 140 and 150 are tilted due to a collision or the like and prohibit further tilting of the poles 140 and 150. Yes.

  As shown in FIGS. 4, 6, and 7, in the axial direction of the pin 120 provided along the rotation center axis, the release plate 180 includes a cam 170, poles 140 and 150, guide protrusions 105, 106, 107, and so on. A hole 181 through which the pin 120 is inserted is formed at a position where it is stacked with the layer 108.

  As shown in FIGS. 7 and 8, the cam 170 is formed with protrusions 176 and 177 protruding toward the ratchet 130, and these protrusions 176 and 177 are formed at the edge of the hole 181 of the release plate 180 and are arranged in the radial direction. Are fitted into small elongated holes 182 and 183 extending to For this reason, the cam 170 and the release plate 180 rotate in conjunction with each other.

As shown in FIGS. 4 and 7, the release plate 180 is formed with convex portions 183 and 184 that protrude toward the rotation plane of the ratchet 130 of the poles 140 and 150.
On the other hand, as shown in FIGS. 4 and 8, the projections 183 and 184 of the release plate 180 are engaged with the surfaces parallel to the rotation plane of the ratchet 130 of the poles 140 and 150, and the release plate 180 rotates. As a result, cam grooves 144 and 154 are formed as concave portions having side wall surfaces set in a shape in which the external teeth 141 and 151 of the poles 140 and 150 move away from the internal teeth 133 of the ratchet 130. ing.

  As shown in FIGS. 7 and 8, spiral springs 191 and 195 as first urging means have inner ends hooked to hooks 111 and 112 of the base plate 100, and outer ends are stepped portions 178 and 178 of the cam 170, respectively. 179, and the cam 170 is urged to rotate so that the cam 170 pushes the back surface of the poles 140 and 150.

  The operation of the upper lock mechanism 59 having the above configuration will be described. Normally, the cam 170 pushes the back surface of the poles 140 and 150 due to the urging force of the spiral springs 191 and 195, and the external teeth 141 and 151 of the poles 140 and 150 mesh with the internal teeth 133 of the ratchet 130. The rotation of the upper arm 77) 130 is prohibited (locked state).

  Here, when the pin 120 is rotated and the cam 170 is rotated in the clockwise direction against the urging force of the spiral springs 191 and 195 in FIG. 8, the pressing of the cam 170 on the back surfaces of the poles 140 and 150 is released. At the same time, the projections 183 and 184 of the release plate 180 are guided by the cam grooves 144 and 154 of the poles 140 and 150, and the outer teeth 141 and 151 of the poles 140 and 150 are separated from the inner teeth 133 of the ratchet 130. The poles 140 and 150 are retracted, the meshing between the external teeth 141 and 151 of the poles 140 and 150 and the internal teeth 133 of the ratchet 130 is released, and the ratchet (second upper arm 77) 130 can be tilted (unlocked). Status).

  When the second upper arm 77 is tilted to a desired angle and the operation force to the pin 120 is released, the biasing force of the spiral springs 191 and 195 causes the cam 170 to push the back surface of the poles 140 and 150, The teeth 141 and 151 mesh with the inner teeth 133 of the ratchet 130 again, and the ratchet (second upper arm 77) 130 is returned to the state where the rotation is prohibited.

  Returning to FIGS. 1 and 2, an operation lever 59 a is attached to one end portion of the pin 120 protruding to the outside from the upper lock mechanism 59 so as to rotate integrally with the pin 120. A lever 201 is attached to the other end of the pin 120 protruding outward from the upper lock mechanism 120 so as to rotate integrally with the pin 120. An operation lever 57a is attached to one end portion of the pin 120 'protruding outward from the lower lock mechanism 57 so as to rotate integrally with the pin 120'.

  A spring locking portion 203 is formed at a location other than the rotation center of the lever 201. A first bracket 207 having a spring locking portion 205 is attached to the upper portion of the second upper arm 77.

  Then, the other end of a spring (tension coil spring) 211 as a second urging means whose one end is locked to the spring locking portion 205 of the first bracket 207 is locked to the spring locking portion 203. ing.

  The position of the spring locking portion 205 of the first bracket 207, the mounting position of the lever 201 in the rotational direction with respect to the pin 120, and the position of the spring locking portion 203 of the lever 201 are related to the engagement of the upper lock mechanism 59 with the spring 211. The operation lever 59a is urged in the direction in which the external teeth 141, 151 of the poles 140, 150 as the mating parts are disengaged from the internal teeth 133 of the ratchet 130 as the engaged parts, and the external teeth (engagement) of the poles 140, 150 Portion) 141, 151 is set at a position where the urging force increases as the inner portion (engaged portion) 133 of the ratchet 130 is separated. Specifically, as shown in FIG. 11A, when the external teeth (engagement portions) 141 and 151 of the poles 140 and 150 are engaged with the internal teeth (engaged portions) 133 of the ratchet 130. FIG. 11 shows that the distance (r1) between the force acting line (l1) of the spring 211 and the rotation center (pin 120) of the lever 201 is short, and the lever 201 is rotated counterclockwise from the state of FIG. As shown in (b), the more the outer teeth (engagement portions) 141 and 151 of the poles 140 and 150 are disengaged from the inner teeth (engaged portions) 133 of the ratchet 130, the action line of the force of the spring 211. The spring 211 and the lever 201 are provided so that the distance (r2) between (l2) and the rotation center (pin 120) of the lever 201 becomes longer.

  In this embodiment, a knob for unlocking the upper lock mechanism 59 is provided at a place other than the operation lever 59 a, and the operation force of this knob is transmitted to the lever 201 via the cable 241. ing.

  Further, in this embodiment, upper locking mechanisms are provided on both sides of the seat back, and an operating force is transmitted to the other upper locking mechanism via a cable 243 locked to the lever 201.

According to the above configuration, the following effects can be obtained.
(1) The urging force of the spiral springs 191 and 195 as the first urging means moves the external teeth (engagement portions) 141 and 151 of the poles 140 and 150 to move the external teeth (engagement portions) 141 and 151. Is gradually increased until it is completely detached from the internal teeth (engaged portion) 133 of the ratchet 130.

However, in the spring 211 as the second urging means, the external teeth 141 and 151 of the poles 140 and 150 as the engaging portions of the upper lock mechanism 59 are disengaged from the internal teeth 133 of the ratchet 130 as the engaged portions. The operation lever 59a is urged in the direction, and the urging force increases as the outer teeth (engagement portions) 141, 151 of the poles 140, 150 are separated from the inner teeth (engaged portions) 133 of the ratchet 130. Thus, the increase in the urging force of the spiral springs 191 and 195 is offset by the increase in the urging force of the spring 211, and the external teeth (engagement portions) 141 and 151 are connected to the internal teeth of the ratchet 130. (Engaged part) The fluctuation of the operating force when the detachment from the 133 is reduced.
(2) The spring 211 as the second urging means has an operating lever in a direction in which the outer teeth 141 and 151 of the poles 140 and 150 as the engaging portions are disengaged from the inner teeth 133 of the ratchet 130 as the engaged portions. The biasing force increases as the outer teeth (engaging portions) 141 and 151 of the poles 140 and 150 are separated from the inner teeth (engaged portions) 133 of the ratchet 130. That is, the urging force of the spring 211 is small when the external teeth (engagement portions) 141 and 151 of the poles 140 and 150 are engaged (engaged) with the internal teeth (engaged portions) 133 of the ratchet 130.

Therefore, the engagement force (locking force, engagement force) in the state where the external teeth 141, 151 of the poles 140, 150 as the engaging portions are engaged (engaged) with the internal teeth 133 of the ratchet 130 as the engaged portions is a specification. It is possible to keep the necessary minimum fluctuations while satisfying
(3) As in the present embodiment, the operation lever 59a is a hindrance to the seat occupant of the rear seat, so that the lever length cannot be secured sufficiently. However, by appropriately setting the urging force of the spring 211, the operation lever 59a is used when the outer teeth 141, 151 of the poles 140, 150 as the engaging portions are detached from the inner teeth 133 of the ratchet 130 as the engaged portions. The operating force can be reduced.

The effects (1) to (3) will be described with reference to FIG. The vertical axis represents the operating force (torque) of the operating lever 59a of the upper lock mechanism 59, and the horizontal axis represents the rotation angle of the operating lever 59a.
The plot (■) shows the operating force (torque) when the spring 211 is provided, the plot (▲) shows the conventional operating force (torque) without the spring 211, and the plot (X) shows the biasing force (torque) of the spring 211. ing.

By providing the spring 211, it can be seen that the locking force in the locked state is kept to the minimum necessary fluctuation while the specification is satisfied, the fluctuation in the unlocking operation force is small, and the unlocking operation force is small.
(4) Since the unit 56 of the lower lock mechanism 57 and the unit 58 of the upper lock mechanism 59 are the same, the parts (units) can be shared.

The present invention is not limited to the above embodiment. In the above embodiment, the spring 211 is locked to the lever 201, but may be locked to the operation lever 59a.
Further, the ratchet 130 may be attached to the first upper arm 75 and the base plate 100 may be attached to the second upper arm 77. The number of poles (140, 150) may be one or more, and the biasing of the cam 170 is not limited to the method using the spiral springs 191, 195.

It is a side view of the seat back frame provided with the lock mechanism of the form example. It is sectional drawing in the cutting line AA of FIG. It is a figure which shows the external appearance of an upper locking mechanism. FIG. 4 is a cross-sectional view taken along a cutting line CC in FIG. 3. FIG. 4 is a rear view of FIG. 3. FIG. 4 is a cross-sectional view taken along a cutting line DD in FIG. 3. It is sectional drawing in the cutting line EE of FIG. FIG. 8 is a diagram in which the release plate of FIG. 7 is removed. It is a figure explaining the sheet | seat in which the locking mechanism of the example was provided. It is a figure explaining the sheet | seat provided with the locking mechanism of this invention. It is a figure explaining the attachment relation of the lever of a form example, and a spring (tension spring). It is a figure explaining an effect. It is a partially broken view of a conventional lock mechanism. FIG. 14 is a cross-sectional view taken along line AA in FIG. 13. FIG. 15 is a cross-sectional view taken along a cutting line BB in FIG. 14.

Explanation of symbols

59 Upper lock mechanism 201 Lever 211 Spring

Claims (5)

A first member;
A second member rotatably provided on the first member; the first member; an engagement portion provided on one of the second members; the first member; The engaged portion provided on the other member of the two members, wherein the engaging portion can be engaged and disengaged, and prohibits rotation of the second member relative to the first member when engaged, and the engaging portion A unit composed of first urging means for urging in a direction of engaging the engaged portion;
Unlocking means for releasing the engaging part from the engaged part against the urging force of the urging means;
In the locking mechanism consisting of
The unlocking means is a lever rotatably provided on the unit;
Further, the lever is urged in the direction in which the engaging portion is detached from the engaged portion, and the urging force increases as the engaging portion is separated from the engaged portion. A locking mechanism comprising a biasing means. The second urging means is
One end is locked to either the first member side or the second member side,
The lock mechanism according to claim 1, wherein the other end portion is a tension spring engaged with the lever. When the engaging part is engaged with the engaged part, the distance between the line of action of the force of the tension spring and the rotation center of the lever is short,
As the engagement portion is disengaged from the engaged portion, the distance between the line of action of the force of the tension spring and the rotation center of the lever is increased.
The lock mechanism according to claim 2, wherein the second urging means and the lever are provided. A lower seat back provided rotatably with respect to the seat cushion, an upper seat back provided rotatably with the lower seat back, and a lower seat back provided between the seat cushion and the lower seat back. In a seat having a lower lock mechanism that is permitted / prohibited, and an upper lock mechanism that is provided between the lower seat back and the upper seat back and permits / prohibits rotation of the upper seat back.
4. The seat according to claim 1, wherein one of the lower lock mechanism and the upper lock mechanism is the lock mechanism according to any one of claims 1 to 3. Of the lower lock mechanism and the upper lock mechanism, the other lock mechanism has the unit according to any one of claims 1 to 3.
The seat according to claim 4, wherein the unit is the same as a unit of one of the lower lock mechanism and the upper lock mechanism.

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