JPH09177461A - Hinge for folding ladder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hinge for an easily foldable ladder by inserting one of the legs of the ladder into one end, and providing inside and outside hinge parts, a circular disk, a tight contact piece, and an angle adjusting rod at the other end. SOLUTION: Locking grooves 108 in a second inside hinge part 104 are formed to have four different angles. A tight contact piece 140 is inserted into a groove 134 in a circular disk 130 and a first locking groove to lock a hinge into place. An angle adjusting rod 170 is rotated to match an recognition mark 178 to a reference mark 180. Then the circular disk 130 is rotated so that the tight contact piece 140 connected to an elastic device 142 is pushed and removed from the locking groove 108. When a second outside hinge part 154 is rotated thereafter, the tight contact piece 140 is pushed at that position by the elastic device 142 and inserted again into the groove 134 and the fourth locking groove. Thus the hinge is locked in that position. Therefore, the hinge can be locked easily in one operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hinge for a folding ladder that folds and locks a ladder at an arbitrary preset angle.

[0002]

2. Description of the Related Art Generally, a hinge for a folding ladder not only connects and supports both legs of the ladder, but also allows the legs to be folded at a desired angle. Such known folding ladders have been disclosed in U.S. Pat. Nos. 4,666,328 and 4,770,559.
No. Of these, US Patent No. 4,6
No. 66,328 is shown in FIG. First leg 10
Has a disk-shaped disk portion 12 at one end. An open hole 14 is provided at the center of the disc portion 12. A pair of first insertion holes 16 provided on both sides close to each other around the opening 14 and a second insertion hole 1 close to the first insertion hole 16.
8 are formed.

On the other hand, the second leg 20, which is joined to the other leg of the ladder according to the first leg 10, is composed of two parts, a second outer leg 21 and a second outer leg 25. There is. One end of the second outer leg portion 21 is joined to the leg of the ladder, and the other end constitutes a disc-shaped second outer disc portion 22. The second outer disc portion 22 has a large number of contact holes 23 circumferentially arranged on the surface thereof. Further, in response to this, the circular actuating plate 30 is provided with a large number of opened second contact holes 32. The circular actuating plate 30 is configured such that one end surface of the circular actuating plate 30 is connected to the second outer disc portion 22 by a spring so that the first contact hole 23 and the second contact hole 32 are offset to some extent. On the other hand, the second inner leg 2
5, the legs of the ladder are joined to one end, and the second inner disk portion 26 is formed at the other end. An opening is formed in the center of the second inner disk portion 26, and a spring device 27 is formed around it. A thin plate 28 is placed on the upper surface extending in the axial direction from the spring device 27, and both ends thereof are fixed to the surface of the second inner disc portion 26 symmetrically from the central axis.

Double protrusions 29 are formed near both ends of the thin plate 28 and are inserted into the first insertion hole 16. The double protrusion 29 is configured such that one protrusion is longer than the other protrusion and can penetrate the first insertion hole 16 and the second contact hole 32 and the first contact hole 23 connected to the first insertion hole 16.
Further, the disc portion 12 and the second portion of the first leg portion 10 described above
The center of the inner and outer discs of the leg is pierced into the hollow shaft 42, and its ends are attached by the ring 44. The hollow shaft 42 is attached to the pressing rod 4.
It is bonded to 0 with a connecting pin 46. Also, connection pin 4
A protrusion 6 is formed at one end thereof so as to protrude in one direction. The connecting pin 46 is located between the second outer disc portion 22 and the disc portion 12, and the pushing rod 40 is pushed and detached, so that the push rod 40 is pushed and detached in the second insertion hole 18. . Therefore, in the hinge having such a structure, by pressing the pressing rod 40, the thin plate 28 connected to the pressing rod 40 is pressed.
Press to detach the double protrusion 29. Therefore, both legs of the hinge are rotatable.

After that, if the user positions it at a desired angle, it is restored by the spring device 27, the double protrusion 29 is inserted into the first insertion hole 16 again, and the ladder can be folded and fixed at a desired angle. become.

However, as shown in FIG. 1, in the conventional hinge for a folding ladder, both legs of the folding ladder connected to the hinge are adjusted at a desired angle, and the double protrusion 29 is formed on the hinge. Corresponding first insertion hole 16, second contact hole 32 and first contact hole 23
It becomes possible to be locked by inserting and fitting it one by one. That is, in such a conventional hinge, protrusions should be inserted into a large number of apertures in order to fold and lock the ladder at a desired angle. Therefore, the user should match the protrusions with all the openings and pass them through. Therefore, it takes a long time to fold and lock the ladder.

[0007]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a hinge for a folding ladder which is easy to fold.

[0008]

The structure of the present invention for achieving the above-mentioned object of the present invention is such that a ladder composed of two legs is folded at a desired angle for a user and fixedly locked. In a hinge for a tatami-type ladder, one leg of the ladder is inserted into one end, and at least one locking groove is formed in the other end at the arbitrary angle, and the central portion of the substantially joint portion is axially attached. An inner hinge portion having a first inner hinge portion and a second inner hinge portion, and the other end portion of the ladder is inserted into one end surface of the ladder, and the other end surface of the inner hinge portion is composed of a pair of shafts. The outer hinge portion including the attached first outer hinge portion and the second outer hinge portion is placed between the first inner hinge portion and the second inner hinge portion, and the substantially central portion is pivotally attached. It is movable, and a curved surface is formed on a part of the outer peripheral surface only in the direction opposite to the rotation forward direction. A circular plate having a recessed groove, and a contact piece that is connected to an elastic device formed toward the substantially central portion of the circular plate and that is compressed by the elastic device and is in close contact with the outer peripheral surface of the circular plate. A rotary shaft that is placed from one of the first hinge portion and the second hinge portion toward the other side and that extends uniaxially from the surface is the first hinge portion, the circular plate, and the second hinge. A folding piece that penetrates the portion and is provided with a preventive piece for preventing attachment and detachment at the tip thereof so as to be rotatable, and an angle adjusting rod that is brought into close contact with the circular plate and is rotated integrally with the rotating shaft. Located on a hinge for a tatami ladder.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 2 is a perspective view showing a hinge for a folding ladder according to the present invention. The hinge comprises an inner hinge part 100 and an outer hinge part 150 to which both legs of the ladder are joined. The inner hinge part 100 and the outer hinge part 150 are pivotally connected to each other, and the angle adjusting rod 170 is connected to this shaft. Further, the angle adjusting rod 170 has a groove 176 formed in a part of the outer peripheral surface thereof, and an outer surface of the outer hinge portion 150 located on the perpendicular line to the groove 176 is provided with an operating hole 153.

Further details will be described with reference to FIGS. 3 and 4. 3 is a front perspective view showing a hinge for a folding ladder according to the present invention, and FIG. 4 is a rear perspective view showing the hinge. The inner hinge portion 100 includes a first inner hinge portion 102 and a second inner hinge portion 104. A first protrusion 112 is formed on the surface of the first inner hinge portion 102, and a first insertion groove 110 is formed on the surface of the second inner hinge portion 104 corresponding thereto. In this way, the first protrusion 112 is formed into the first insertion groove 110.
The first inner hinge portion 102 and the second inner hinge portion 104 can be joined by being inserted into the.
Further, a large number of locking grooves 108 are formed on the outer peripheral surface of the first inner hinge portion 100. The number of locking grooves 108 is
It means the number of angles that can be folded and locked. However, in the figure, the 0 ° and 40
By limiting to four angles of °, 105 ° and 180 °, the number of locking grooves 108 becomes four. In addition, the ratchet device 160 is provided on the surface of the second inner hinge 104.
Is configured. This device includes a ratchet piece 162 having elasticity to some extent, one end of which is fixed to the second inner hinge 104 and the other end of which is bent in a ring shape. The outer hinge part 150 is the first outer hinge part 1.
52 and the second outer hinge portion 154 are separated and coupled. A second protrusion 157 is formed on the surface of the first outer hinge portion 152, and the second outer hinge portion 1 corresponding thereto is formed.
A second insertion groove 159 is formed on the surface of 54. By thus inserting the second protrusion 157 into the second insertion groove 159, the first outer hinge portion 152 and the second outer hinge portion 154 can be joined together. An operating piece 153 is formed at one end of the outer hinge portion 150 so as to face the central axis. Inside the operation hole 153, a contact piece 140 connected by a compressed elastic device 142 is placed. The contact piece 140 is configured such that the width of the portion to be inserted and pitted into the locking groove 108.

On the other hand, the first inner hinge portion 102 and the second inner hinge portion 102
A circular plate 130 having a groove 134 is placed between the inner hinge 104 and the inner hinge 104. The circular plate 130 has a groove 134 formed in a part of its outer peripheral surface. This groove 13
4 has a curved surface on one side and a steep slope on the other side. Further, an insertion groove 132 is formed in the circumferential direction on the back surface of the circular plate 130 in contact with the second inner hinge portion 104. The insertion groove 132 has a ratchet piece 1
The ring-shaped end of 62 is inserted. Therefore, the circular plate 130 can be rotated only in one direction.

Further, the first hinge portion 106, the circular plate 130, and the second hinge portion 156 thus constructed have a rotating shaft 172 extending from an angle adjusting rod 170 at substantially the center thereof.
The shaft is attached. The rotary shaft 172 has its end fixed by a locking piece 174 and can be fixed without being detached. Further, the rotating shaft 172 is configured to have a pair of flat surfaces 173 facing each other on a part of its outer peripheral surface that penetrates and contacts the circular plate 130. In this structure, the angle adjusting rod 170 can be rotated integrally with the circular plate 130 by bringing the rotating shaft 172 into close contact with the circular plate 130. The angle adjusting rod 170 is provided with a groove 176 on the outer peripheral surface thereof. The groove 176 is formed in a straight line with the groove 134 of the circular plate 130 axially mounted on the shaft as a reference. As a result, the recognition mark 17 is provided on the surface of the angle adjusting rod 170.
8 are provided. The angles most frequently used by this ladder are 0 °, 40 °, 105 ° and 180 °.
Moreover, a reference mark 180 is formed in the vicinity of the outer peripheral surface of the reference mark 180 so as to serve as a reference corresponding to the recognition mark 178.
In this way, the recognition mark 178 corresponding to the reference mark 180 indicates an angle formed by both legs of the ladder when the angle adjusting rod 170 is rotated and locked. This aligns the recognition mark 178 with the desired angle with the reference mark. This one
The ladder can be folded at a stretch to obtain a desired angle only by operating the angle adjusting rod 170 once.

An actual operation example will be described in detail with reference to FIG. 5A to 5C are views showing an operation example in which the hinge for the folding ladder according to the present invention is folded and locked at an angle of 0 ° to 180 °. This drawing shows only the circular plate and the second hinge part in order to show an operation example.

Of these, FIG. 5A is a view showing a hinge locked at an angle of 0 °. As shown in the figure, the locking groove 108 of the second inner hinge portion 104 is 0 °,
The first locking groove 108a and the second locking groove 108 are formed by four different angles of 40 °, 105 ° and 180 °.
b, third locking groove 108c and fourth locking groove 108d
It is composed of two locking grooves. However, in this figure, the concave groove 134 of the circular plate 130 and the first locking groove 108a
It is shown that the contact piece 140 is attached to the hinge and the hinge is fixedly locked at an angle of 0 °. Of course, in this state, the recognition mark 0 ° on the upper surface of the angle adjusting rod is aligned with the reference mark. After that, as shown in FIG. 5B, the user rotates the angle adjusting rod in the direction indicated by the arrow to align the recognition mark 180 ° shown on the upper surface with the reference mark. As a result, the circular plate 130 connected thereto is rotated, and the elastic device 14 is rotated.
The contact piece 140 connected to 2 is pushed and removed from the locking groove 108. After that, when the user operates the second outer hinge portion 154 by 180 degrees, the contact piece 14 is placed at the position where the hinge is 180 degrees along with a clicking sound.
0 is pushed by the elastic device 142 so that the groove 13 of the circular plate 130
The contact piece 140 is inserted into the fourth and fourth locking grooves 108d again. Therefore, the hinge can be fixedly locked at the 180 ° position. In addition, this method allows the hinge to be folded and locked at a desired angle not only at 180 ° but also at any other desired angle.

[0015]

As described above, the hinge for the folding ladder according to the present invention constitutes a recognition mark indicating the folding angle most often used for the angle adjusting rod axially attached to the circular plate,
Further, by defining a reference mark as a reference and aligning the recognition mark with the reference mark, the hinge for the ladder can be easily folded and locked by only one operation.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a hinge for a folding ladder according to one embodiment of the prior art.

FIG. 2 is a perspective view showing a hinge for a folding ladder according to the present invention.

FIG. 3 is an exploded perspective view showing a hinge for a folding ladder according to the present invention as viewed from the front.

FIG. 4 is an exploded perspective view showing the hinge for the folding ladder of FIG. 3 as viewed from the rear side.

5A to 5C are diagrams showing an operation example in which a hinge for a folding ladder according to the present invention is folded at an angle of 0 ° to 180 °.

[Explanation of symbols]

 100 Inner Hinge Part 102 First Inner Hinge Part 104 Second Inner Hinge Part 106 First Hinge Part 108 Locking Groove 110 First Insertion Groove 112 First Protrusion 130 Circular Plate 134 Groove 140 Contact Piece 142 Elastic Device 150 Outer Hinge Part 152 First Outer Hinge Part 153 Working Hole 154 Second Outer Hinge Part 156 Second Hinge Part 157 Second Protrusion 159 Second Insertion Groove 160 Ratchet Device 162 Ratchet Piece 170 Angle Adjusting Rod 172 Rotating Shaft 173 Plane 174 Preventing Piece 176 Groove 178 Recognition mark 180 Reference mark

Claims (4)

[Claims] 1. A hinge for a folding ladder in which a ladder composed of two legs is folded at a desired angle and fixedly locked, and one leg of the ladder is inserted into one end of the ladder. An inner hinge part having a first inner hinge part and a second inner hinge part in which at least one locking groove is formed at the other end at the arbitrary angle, and the central part of the substantially joint part is pivotally attached. An outer hinge part having a first outer hinge part and a second outer hinge part, in which the other end of the ladder is inserted into one end face and the other end face is axially attached to the inner hinge part in one set. And is placed between the first inner hinge portion and the second inner hinge portion and has a substantially central portion pivotally attached so as to be rotatable, and a part of the outer peripheral surface is curved only in a direction opposite to the rotational forward direction. A circular plate having a concave groove having a surface, and a shape so as to face a substantially central portion of the circular plate. A close contact piece that is connected to the elastic device and is compressed by the elastic device to be in close contact with the outer peripheral surface of the circular plate; and one of the first hinge part and the second hinge part to the other side. The pivot shaft, which is placed so as to face toward and extends uniaxially from the surface, has the first hinge portion, the circular plate, and the second hinge portion.
The hinge portion is provided with a preventive piece for preventing attachment / detachment at the tip thereof so as to be rotatable, and an angle adjusting rod that is brought into close contact with the circular plate and is rotated integrally with the rotating shaft is provided. Hinge for folding ladder. 2. The other end having elasticity, the one end being attached so as to face the tangential direction in the vicinity of a penetrating shaft of any one of the first inner hinge part and the second inner hinge part. A circular ratchet device, which is inserted into and removed from a large number of circumferentially formed insertion grooves of the corresponding circular plate to allow the circular plate to rotate only on one side and to maintain a fixed position. A hinge for a folding ladder according to claim 1. 3. The angle adjusting rod is provided with a groove so that the position of the groove can be divided into the same position extending uniaxially from the groove formed in the circular plate. Hinge for the described folding ladder. 4. The ladder according to claim 1, wherein a recognition mark is provided on the surface of the angle adjusting rod, and the recognition mark is aligned with a reference mark so that the ladder is folded at a desired angle at a stroke and locking is performed. Hinge for the folding ladder of.