JPH0614619Y2 - Armrest position adjustment mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a position adjusting mechanism of an armrest.

(Prior Art) As a conventional position adjusting mechanism of an armrest, one having a spring coupler is known, but since the structure of the spring coupler is complicated, the position adjusting mechanism necessarily has a complicated structure. Assembly on the back becomes complicated. As a position adjusting mechanism for coping with this, Japanese Patent Application Laid-Open No. 64-4075 disclosed by the present applicant.
There is a mechanism shown in Japanese Patent No.

The position adjustment mechanism includes a fixed shaft fixedly supported by a support member, which is provided with left and right inclined friction engagement surfaces that incline in directions opposite to each other with respect to the axis with a space provided on the outer periphery, and the inclined friction engagement members. A first rotating member that has an inclined friction engagement surface that engages and disengages with either of the mating surfaces, is rotatably assembled to the outer periphery of the fixed shaft, and is fixed to the member to be adjusted; A second rotating member that has an inclined friction engagement surface that engages or disengages with either of the mating surfaces, is rotatably assembled to the outer periphery of the fixed shaft, and that rotates by an external operation;
Both of these rotating members contact and separate from each other by relative rotation,
At the time of contact, the inclined frictional engagement surfaces facing each other are frictionally engaged by the axial force thereof. Therefore, a preferred embodiment of the position adjusting mechanism is as follows.
It is as per (1) and (2). That is, (1) one of the inclined friction engagement surfaces of the fixed shaft is formed of a right-hand thread portion, the other inclined friction engagement surface is formed of a left-hand thread portion, and each of the rotary members is It is a nut member that is screwed into the screw member so as to be able to move forward and backward.

(2) Each inclined friction engagement surface of the fixed shaft is formed of an inclined cam surface, and the rotating member has an inclined cam surface that engages with and disengages from the inclined cam surface. It is a cam member to be fitted.

(Problems to be solved by the invention) By the way, in the position adjusting mechanism having the above-described structure, although the structure itself is simplified, there is a problem that the workability of the screw portion and the cam portion is poor. Therefore, an object of the present invention is to further simplify the structure of the position adjusting mechanism and improve workability.

(Means for Solving the Problems) An armrest position adjusting mechanism according to the present invention is fixed to a seat back and protrudes from one side of the seat back to support the armrest at its base end in a vertically rotatable manner. A fixed shaft, a first cam member integrally provided on the fixed shaft, an operation shaft rotatably supported by the armrest and arranged in parallel with the fixed shaft, and integrally provided on the operation shaft. A second cam member having an outer peripheral cam surface that releasably faces the outer peripheral cam surface of the first cam member, and an operation handle integrally provided on the operation shaft for rotating the operation shaft, The outer peripheral cam surfaces of both cam members are formed into a cam shape that engages with each other when the armrest is rotated downward by a predetermined amount, and restricts further downward rotation of the armrest. .

(Operation and effect of device) In the position adjusting mechanism having such a configuration, the second cam member is rotated in both forward and reverse directions by operating the operation handle,
The outer peripheral cam surface of the same cam member can be moved back and forth with respect to the outer peripheral cam surface of the first cam member. For this reason, the armrest can be rotated downward by a rotation amount corresponding to the distance between the outer peripheral cam surfaces, and when the armrest rotates by a predetermined amount, the outer peripheral cam surface of the second cam member is rotated by the outer peripheral cam surface of the first cam member. It engages with the surface and restricts downward rotation of the armrest. As a result, the armrest is held at a desired turning position, and the turning position can be changed to an arbitrary position by operating the operation handle described above.

By the way, in the position adjusting mechanism, as described above, the number of constituent members is small and the structure is simple, and since each cam member is formed with an arcuate cam surface on its outer periphery, the workability of each cam member is improved. It is good.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show an armrest position adjusting mechanism according to the present invention. The position adjusting mechanism 10 is arranged in the armrest 20a shown in FIG. 4 and supports the armrest 20a on one side of the seat back 20b.

The position adjusting mechanism 10 includes a fixed shaft 11, an operating shaft 12, first and second cam members 13 and 14, and an operating handle 15. The fixed shaft 11 supports the armrest 20a on one side of the seat back 20b, and is rotatably assembled to the frame main body 21 and the subframe 22 constituting the frame 20c of the armrest 20a. The fixed shaft 11 has a seat back 20 at one end.
It is fixed to the back frame that constitutes b. In addition,
The frame 20c of the armrest 20a includes a second subframe 23 in addition to the frame body 21 and the subframe 22 described above. The operation shaft 12 is rotatably assembled to the frame body 21, and is positioned in parallel with the fixed shaft 11 at a predetermined interval. The first cam member 13 is integrally rotatably mounted on the fixed shaft 11, and the second cam member 14 is integrally rotatably mounted on the operating shaft 12. Both of the cam members 13 and 14 are frame main bodies. 21 and the subframe 22 are located on the same plane. Each cam member 13, 14 is provided with an arcuate cam surface (outer peripheral cam surfaces 13a, 14a) on the outer periphery thereof, and the outer peripheral cam surfaces 13a, 14a gradually project outward from their base ends toward the tip side. It is formed in the shape of. Each cam member 13, 14 has its outer peripheral cam surface 1
When the frames 3a and 14a face each other in a disengageable manner and the frame 20c is rotated downward, the frames 3a and 14a are engaged at a predetermined rotation position, and further rotation of the frame 20c is restricted. The operation handle 15 is integrally attached to the outer end of the operation shaft 12.

In the position adjusting mechanism 10 having such a structure, the armrest 20a is supported on one side of the seat back 20b shown in FIG. 4, and the first cam member 14 is provided with the first arm member 20a as shown in FIG.
The engagement with the cam member 13 holds the cam member 13 at a predetermined rotation position. Thus, FIG. 3 shows the operating state of the position adjusting mechanism 10. In the figure, the solid line shows the holding state of the frame 20c (armrest 20a). To change the holding state shown by the two-dot chain line, first rotate the operating handle 15 to the state shown by the one-dot chain line. To do. As a result, the second cam member 14 engaged with the first cam member 13 rotates to be separated from the first cam member 13 by a predetermined amount, and allows the frame 20c to rotate downward. Therefore, when the frame 20c is rotated downward, the second cam member 14 engages with the first cam member 13 at a predetermined rotation position, and the frame 20c is restricted from rotating further downward. The state shown by the two-dot chain line is maintained. The rotation position of the frame 20c is determined by the distance between the cam members 13 and 14.

By the way, in the position adjusting mechanism 10, as described above, the number of constituent members is small and the structure is simple, and the outer peripheral cam surfaces 13a and 14a of the cam members 13 and 14 are simple in shape and the cam members 13 and 14 are simple. Has good workability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional plan view of a position adjusting mechanism according to an embodiment of the present invention, FIG. 2 is a side view in the direction of arrow II-II in FIG. 1, and FIG. FIG. 4 is an operation explanatory view of the mechanism, and FIG. 4 is a perspective view of a seat provided with an armrest supported by the mechanism. Explanation of reference numerals 10 ... Position adjustment mechanism, 11 ... Fixed axis, 12 ... Operation axis, 13, 14 ... Cam member, 13a, 14a.
Outer peripheral cam surface, 20a ... armrest, 20b ... seat back, 20c ... frame, 21 ... frame body, 22 ... subframe.

Claims (1)

[Scope of utility model registration request] 1. A fixed shaft that is fixed to a seat back and projects from one side of the back to support an armrest at its base end in a vertically rotatable manner, and a fixed shaft integrally provided on the fixed shaft. One cam member, an operation shaft that is rotatably supported by the armrest and is parallel to the fixed shaft, and is integrally provided on the operation shaft and can be engaged with and disengaged from the outer peripheral cam surface of the first cam member. A second cam member having opposing outer peripheral cam surfaces and an operation handle integrally provided on the operation shaft for rotating the operation shaft are provided, and the outer peripheral cam surfaces of the both cam members are located below the armrest. A position adjusting mechanism for the armrest, which is formed in a cam shape that engages with each other during a fixed amount of rotation to restrict further downward rotation of the armrest.