JPS6041950Y2 - wheelchair foldable back frame - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a foldable back frame for a wheelchair, and the back frame equipped with folding armrests can be folded extremely easily.

The wheelchair to which the back frame of the present invention is attached is published in Japanese Patent Publication No. 52-253.
This was proposed in No. 45, and is intended to more effectively achieve the purpose of use as a foldable wheelchair by using it in the seat frame of the wheelchair.

To briefly explain the structure of the wheelchair in FIGS. 1 and 2, each end of a pair of X-shaped support rods 1, which are pivotally supported at the center, are connected to both ends of the wheelchair via joints 2. A frame body is attached, and the frame body has a seat frame 4 at the upper end of the column 3 and a mounting frame 5 at the lower end.
The inner ends of the front and rear leg frames 7 and 8 are fitted and pivoted into the mounting frame 5, and the front leg frame is provided with a footrest 9 and casters 10, and the rear leg frame 8 is provided with a main frame. 11 is rotatably attached to the shaft.

For such a wheelchair, the conventional back frame is inserted into the seat frame 4 so as to be slidable up and down, and fixed with pins at a desired height position.

However, the operation of inserting the pins into the pin holes in the back frame was surprisingly complicated and time-consuming, and the folding structure was not desirable.

The present invention has a structure in which the locking mechanism is opened by one-touch operation of the lever, and when the predetermined lying down and standing positions are reached, the locking mechanism is automatically locked, allowing for extremely easy folding and assembly operations.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

Reference numeral 13 denotes a back frame according to the present invention, which stands up at the rear end of the seat frame 4 as shown in FIG.
It lies forward along the line.

The horizontal arm frame 14 attached to the upper end of the back frame 13 is unlocked by lifting it, and is placed along the collapsed back frame as shown in FIG.

The back frame 13 is formed of a square pipe made of light metal, and the lower end of the back frame 13 is integrally fixed with a solid metal material by welding or screws.

As shown in FIGS. 3 and 4, the seat frame 4 on which the back frame 13 is erected and fixed is formed of a square metal pipe, and a pair of support walls 15, 15' are erected from both sides on the upper surface of the rear end. , a reinforcing rear wall 16 is provided between the rear ends of both supporting walls.

The lower part of the back frame 13 is pivotally connected to both support walls 15+15' by bolts 17 and nuts 18.

The lower surface of the back frame 13 is formed into an arcuate surface whose radius is the length from the center of the bolt 17 to the upper surface of the seat frame 4.

On the other hand, a tubular sleeve 21 is fixed between the upper and lower walls 19 and 20 of the seat frame 4 along a downward perpendicular line from the center position of the bolt 17, and a pin 22 is slidably inserted into this sleeve 21. .

A coil spring 24 is interposed between the step formed by the small diameter portion at the bottom of the bottle 22 and the lower wall 23 of the sleeve 21 to urge the pin 22 upward.

A through hole 25 is bored in this pin, and the tip of a lever 26 inserted from the rear of the seat frame 4 is fitted into the through hole 25.

The center portion of this lever 26 is pivoted to a support shaft 28 mounted on both side walls of the rear portion of the seat frame.

Engagement recesses 29 and 30 are formed in the front and lower surfaces of the back frame 13 and the lower part, into which the tips of the pins 22 fit when the back frame is laid down along the seat frame and when it is erected.

A two-pronged joint 2 with a support shaft 32 to which an end of an X-shaped support rod 1 is pivotally connected is fixed to the inner surface of the rear end of the seat frame 4 with a bolt 33.

A cladding 36 is provided on the inner surface of the back frame 13 via a mounting member 35, and a backrest sheet 37 is attached to the cladding 36 with screws 38.
It is permanently installed.

Furthermore, a sleeve 40 is provided between the front and rear walls at the center of the back frame,
A pin 42 that is biased forward by a coil spring 41 is attached to the sleeve 40, and when the back frame (not shown) is once collapsed and locked, the seat of the pin 42 is lifted when the back frame is unlocked and lifted. It has a structure that swings upward due to the elastic force against the frame 4.

Further, as shown in FIG. 4, a spring 44 made of an elastic filament is wound around the bolt 17, and its base end engages with a screw 45 and its tip engages with the rear surface of the back frame, so that the back frame 13 In addition to preventing shaking due to manufacturing errors in the upright position, the pin 22
It is designed so that it always tilts forward when the locked state is released.

The operation of the present invention configured as above will be explained.

As shown in Figure 1, when folding from the unfolded and assembled state so that a disabled person can ride in a wheelchair, it is possible to compact it to the state shown in Figure 2 by pressing the main parts on both sides inward. can.

The folding operation of the back frame 13 according to the present invention can be performed at any time before or after the folding operation.

It is preferable that the folding operation of the back frame be carried out after grasping and lifting the center part of the upper arm frame 14 and disengaging it from the upper end of the back frame.

To tilt the back frame forward, first, lift the proximal handle of the lever 26 upward so that the tip of the lever 26 touches the pin 22.
Press down.

At this time, the upper end protrusion of the pin 22 is disengaged from the engagement hole 30, and as a result, the back frame 13 is tilted forward by the spring 44.

When the back frame 13 falls down to a position parallel to the upper surface of the seat frame 4, the engagement hole 29 reaches a position directly above the pin 22, the pin 22 elastically fits into the engagement hole 29, and the back column is in this position. Fix it with.

When the back frame 13 falls down on the seat frame 4, the pin 42 has the function of alleviating the fall impact.

When raising the back frame 13, lift the lever 26 and lower the pin 22 to disengage it from the engagement hole 29, and the tip side of the back frame 13 swings upward due to the elasticity of the pin 42. At this time, if the elbow frame 14 is further raised, the pin 22 and the engagement hole 30 will fit, and the back frame will be fixed in the upright position.

The back frame of the present invention, which has the above-mentioned functions, can be folded or unfolded by a simple mechanical operation such as lifting the lever 26 with one touch, so there is no need for labor or skill to operate it, and it is easy to handle this type of wheelchair. Not only is it extremely easy to use, but the vehicle body can be folded compactly, saving storage space when not in use.

[Brief explanation of drawings]

Figure 1 is a side view showing the unfolded and assembled state of the wheelchair using the back frame of the present invention, Figure 2 is a side view showing the wheelchair in Figure 1 folded, and Figure 3 is the attached frame on the seat frame. FIG. 4 is an enlarged partially cutaway side view showing a state in which the back frame having a back frame is arranged in an upright manner, and FIG. 4 is an enlarged partially cutaway rear view of FIG. 3. 1... X-shaped support rod, 3... Support column,
4...Seat frame, 5...Mounting frame, 7. Death・
... Leg stick, 11 ... Main argument, 13 ...
・Back frame, 14...Elbow frame, 15'...Support plate, 17...Bolt, 21.41...
・Sleeve, 22, 42...Pin, 26...
...Lever 29.30...Engagement hole.

Claims (1)

[Scope of utility model registration request] The lower end of the back frame, which has an elbow frame pivoted to its upper end, is pivoted to both support plates that stand up from both sides of the upper surface of the seat frame, so that it can be raised and lowered freely, and the back frame is attached to the lower part of the seat frame where the back frame pivots. A pin is slidably provided which is biased upward so as to fit into the engagement hole when the seat is laid down or erected, and the tip of a lever whose center portion is pivotally connected to the seat frame is inserted into the through hole of the pin. A foldable back frame for a wheelchair, which is characterized by: