JP3586825B2 - Canvas bed folding mechanism - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure in which a canvas-like material such as a canvas is stretched between a pair of right and left rod-shaped members so as to be folded in a short side direction and further folded in a long side direction.
[0002]
[Prior art]
The framework of the canvas bed which is swiveled and folded in the long side direction is provided with a swivel axis above the bar-shaped members of the conventional framework or with a horizontal swivel axis passing through the axis of the horizontally arranged bar-shaped materials. Was.
[0003]
[Problems to be solved by the invention]
In the case where a shaft is provided above the bar-shaped member of the conventional framework, the vicinity of the shaft becomes a large projection, which is a hindrance to use and is dangerous. Further, in the system in which the rod-shaped members are arranged side by side and swung by a horizontal axis passing through the axis, the same problem remains and the width after folding in the short side direction becomes thick. In both cases, the vicinity of the axis tended to be weak, and there was a tendency that this was reinforced and heavier and heavier.
An object of the present invention is to solve these problems and to realize a canvas bed framework that has no extra protrusions on the bed top and near the framework during use, can be folded thinly, and can reduce the load on the shaft. I have.
[0004]
[Means for Solving the Problems]
First, in the framework, a portion whose posture does not change when folded is simply referred to as a frame, and a portion that is turned upward and folded with respect to the frame is referred to as an end frame. In order to achieve the above object, according to the present invention, both the reaction force receiving portion and the shaft as a portion for receiving the reaction force against the tension of the canvas applied to the end frame are provided below the axis of the rod-shaped material of the end frame. The frame has a shaft mounting portion and a force receiving portion for receiving a force from the reaction force receiving portion, which are provided below the axis of the frame. In addition to the shaft for turning upward, the shaft is attached so as to be able to turn laterally.
The center point of the tension of the canvas applied to the end frame and each center point of the reaction force receiver and the shaft are aligned on a straight line.
Also, the turning shaft is not horizontal, and is slightly tilted so that the end frame is pivotally attached to the frame so that the end frame is turned immediately below the frame. At this time, the direction of the shaft and the direction of the resultant force of the canvas tension applied to the end frame can be matched.
When the bed is folded in the short side direction of the bed by reducing the distance between the frameworks on both sides, the bed is shifted by a predetermined dimension in the long side direction so as to overlap.
[0005]
The framework constructed in this way has no obstructions when deployed and used, and has a flat bed surface and a smooth framework. An end frame that is pivotally mounted by two axes so as to be able to pivot in two directions, upward and lateral, can prevent deformation and destruction due to overload when the reaction force receiving member is not meshed with the engaging portion. Since the shaft is below the frame, at first glance, the bending moment is applied to the shaft and it seems to be weak. However, if the three center points of tension, reaction force reception and the shaft are located on one straight line, this straight line Since there is no moment about the center, the bending moment applied to the shaft becomes extremely small, which is rather advantageous in strength. When folded, the end frame turns and comes directly under the frame, so it can be stored in the same thickness as the frame except for near the axis, and can be folded into a thin flat plate. In addition, when the inclination direction of the shaft matches the direction of the tension of the canvas of the end frame, the bending moment applied to the shaft becomes zero. The protruding parts of the frame and the end frame near the pivot shaft attachment part and the force-applying part are slightly displaced in the direction of the long side of the bed and approach and are folded. The parts fit so as to avoid each other.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described based on examples with reference to the drawings. FIG. 1 shows the entire developed side of the canvas bed to which the present invention has been applied, in particular, the folded shape of the end frame 2 by a chain line . FIG. 2 shows the upper surface, and FIG. 3 shows a process of reducing the framework in the short side direction, particularly, a state in which folding is completed by a chain line . As shown in FIG. 2, this product is symmetrical left and right except for the push rod and the connecting pipe. FIGS. 4 and 5 show the upper right portion in a three-dimensional manner. In particular, the chain line indicates the folded shape of the end frame 2 . FIG. 6 is a cross-sectional view showing the vicinity of a portion where the end frame 2 is attached to the frame 1, and shows a folded form of the end frame 2 by a chain line. A frame 1 having both ends hanging vertically and each having a leg is provided on the inside of the leg, and a shaft corresponding to the frame-side shaft mounting portion with one end bent forward and backward by a shaft mounting portion slightly lowered from a horizontal portion. Two end frames 2 serving as attachment portions are axially attached to each other by a shaft 9 to form a frame. Details of the shaft mounting portions of the frame 1 and the end frame 2 are shown in FIGS. 4 and 5, and the shaft mounting portion of the frame 1 has a round pipe shape and has a pair of long holes 17 on the side surface, and can be rotated without loosening outside. The shaft 9 penetrates together with the round hole of the sleeve 15 fitted into the end frame 2, and the end frame 2 is axially mounted via the spacer 16. Instead of putting the sleeve 15 on the outside, a short rod-shaped material having a through hole on the side may be inserted inside. The frames are arranged on the left and right sides, and the upholstery 3 is stretched between them to form a canvas bed. A reaction force receiver 8 is provided below the end frame 2, and a hook-shaped force-receiving portion 10 receiving the reaction force is provided on the frame side. A latch mechanism for preventing the reaction force receiver 8 from accidentally detaching may be added to the force applying portion 10.
[0007]
The center of tension of the cloth 3 applied to the end frame 2, the point 11, the center of the reaction force of the reaction force receiver 8, the point 12, the center of the shaft 9, and the point 13 are on a straight line 14.
The shaft 9 is mounted so as to be slightly inclined from the horizontal as shown in FIG. 6, and its angle is determined so that the portion where the upholstery cloth 3 of the end frame 2 is stretched comes directly below the frame 1. ing. Since the inclination direction of the shaft 9 is determined in relation to the hanging distance of the mounting portion, it can be made to be directly below the horizontal portion of the frame 1 when folded, and can coincide with the tension direction of the canvas when deployed .
As shown in FIGS. 1 and 3, the push rod 6 is fitted to the leg of the upper frame 1 and is connected to the rotatable connecting pipe 4, and is similarly connected to the rotatable connecting pipe 5 to be fitted to the lower frame. The pushed push bar 7 is pin-coupled at the end to form a bed folding / expanding mechanism that can be bent only inward. In the effective length, the connecting pipe 4 is shorter than the connecting pipe 5, but the push rods 6 and 7 have the same length. The mechanism for pushing and spreading the frame on both sides by the push rod and the connecting pipe is an example, and various other mechanisms having the same function are known. When the mechanism is reduced in the short side direction of the bed, a structure suitable for each mechanism is used. May be employed so that the left and right frames are slightly shifted.
[0008]
The operation and function of the embodiment configured as described above will be described. As shown in FIGS. 1 and 2, the overlapping portion of the frame 1 and the end frame 2 does not have any protrusions that come into contact with the body, and realizes a flat bed surface and a smooth framework. At the time of folding, when the reaction force receiving member 8 is disengaged from the force receiving portion 10, even if an excessive force is suddenly applied to the end frame 2, the shaft 9 and the sleeve 15 have the same length as the shaft mounting portion of the frame 1. Since a predetermined angle corresponding to the hole 17 can be turned in the lateral direction, deformation and breakage of the shaft mounting portion can be prevented.
Considering the force acting on the cantilever end frame 2, the resultant force of the distributed load due to the head or leg of the human body is P as shown in FIGS. 1, 2 and 5, the vertical force is P _V , and the horizontal force is horizontal. the force and _{P H.} The reaction force acting on the point 12 with respect to P is Q, and the reaction force acting on the point 13 is R. P _H is a two to three times the normal _{P V.} Since the point of action of P, the center of the reaction force at the point 11 and the reaction force receiving, the center of the point 12 and the center of the shaft 9, and the point 13 are on a straight line 14, the torsional moment about the straight line 14 is Does not occur. Even if the point 12 is not exactly on the same straight line, the closer the point 12 is to the straight line connecting the point 11 and the point 13, the smaller the moment becomes, which has a great effect in practical use. Therefore, no extra bending moment is applied to the shaft 9.
[0009]
Reaction force R _H in the axial 9 by the horizontal force P _H in P is directly as simply guide shaft 9 extending through the Tanwaku 2 is transmitted to the frame 1. Although P is a reaction force R _V vertical force P _V of the load in the axial 9 becomes the bending moment is the product of half the diameter or width of Tanwaku 2, it is small as the value. As described above, it is possible to make the direction of inclination of the shaft 9 coincide with the direction of the tension of the canvas, in which case no bending moment is applied to the shaft 9. Thus, the load applied to the shaft 9 is extremely reduced as a whole.
As described above, the shaft 9 is slightly inclined from the horizontal, and the end frame 2 is turned right under the frame 1 so that both are folded into a flat plate having a thickness equal to the diameter or width of the bar. Be folded. The mounting portion of both shafts 9 and the force applying portion 10 become projections, but when the frames 1 on both sides are folded in the short side direction, they are shifted in the long side direction, and the respective projections are avoided from each other, so that as a whole, It becomes a thin flat plate.
[0010]
【The invention's effect】
Since it is configured, acts and functions as described above, it has the following effects.
The provision of a reaction force receiving member that receives a reaction force against the tension of the canvas and a pivot axis for folding below the end frame realizes a flat bed surface and a smooth framework. In addition to turning the end frame upward, the end frame can also be turned laterally to avoid an unexpected overload and to prevent deformation and breakage of the shaft mounting portion.
An arrangement in which the three centers of tension, reaction force reception, and shaft are arranged on one straight line significantly reduces the load on the shaft and improves the strength.
The one in which the shaft is tilted and the end frame is turned so as to be directly below the frame allows the frame to be folded extremely thinly. When the frames on both sides are folded close to each other in the short side direction and slightly shifted in the long side direction, the frames on both sides folded in a thin plate shape are made closer to each other so that each protrusion avoids each other. Can be folded into a thin flat plate as a whole.
[Brief description of the drawings]
FIG. 1 is a right side view when an embodiment is expanded. The folding process of the end frame is indicated by a chain line.
FIG. 2 is a top view when the embodiment is developed.
FIG. 3 is a top view in which the framework of the folding process is indicated by a solid line, and the folded state is indicated by a chain line, and a part is omitted.
FIG. 4 is an external perspective view in which a part of the end frame 2 near a mounting portion is broken.
FIG. 5 is a perspective view of an upper right portion of the embodiment. The dashed line indicates the folded shape.
FIG. 6 is a sectional view taken along the line AA in FIG. 1; The appearance after folding is indicated by a chain line.
[Explanation of symbols]
Acting on first frame point P 11, the vertical component force 6,7 pushrod Q point 12 of the horizontal force 4,5 Tsugikan P _v P of the resultant force 3 Zhang Bu P _H P 2 end frame tension of the end frame 2 canvas Acting, reaction force against P 8 Reaction force receiving R Acting on point 13, reaction force against P 9 Vertical component force of axis R _v R 10 Force applied parts 11, 12, 13 Point 14 Straight line 15 Sleeve 16 Spacer 17 Slot

Claims (5)

In a canvas bed with a canvas etc. stretched between the frames on both sides, at the end of the bar as a framework, another rod provided with a reaction force receiving below, by a shaft provided below these rods A frame structure of a canvas bed, wherein the frame is attached to a shaft and pivoted upward to be foldable, so that the tension of the canvas applied to the shaft-mounted bar is received by the shaft and the reaction force receiving member. 2. The structure of the canvas bed framework according to claim 1, wherein the frame is pivotally mounted not only upwardly but also laterally. 3. The structure of a canvas bed framework according to claim 1, wherein the three centers of tension, reaction force receiving and shaft are on one straight line. 4. The structure of the canvas bed frame according to claim 1, wherein the pivoted member is pivotally folded by a slanted shaft, and is located immediately below a bar member of the mating member when pivoted. . 5. The bed according to claim 1, 2, 3, or 4, wherein when the frames on both sides are shortened and folded, the bed is displaced in the longitudinal direction of the bed and the projecting portions of both frames are avoided from each other. The structure of the canvas bed framework.

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