JPH1128231A - Wheelchair reverse running prevention mechanism - Google Patents

Abstract

(57) [Summary] [Problem] To use general-purpose industrial products, the wheels do not reverse even if the driver does not hold the drive wheel or the steering wheel while stopping on an uphill, and brakes are applied to the left and right wheels one by one. An easy-to-operate and safe wheelchair reverse running prevention mechanism is provided, in which the wheelchair is not inadvertently rotated even when one of the driving wheels is released when the vehicle is hung. SOLUTION: One-way pulleys which rotate only in a forward direction are detachably attached to positions on left and right wheels which do not hinder the operation of brakes. On a support plate that is easily attached to a part of the vehicle body with screws and nuts,
Attach the built-in toggle clamp of the one-way pulley via another screw and nut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved structure of a wheelchair reverse running prevention mechanism which can be attached to an ordinary wheelchair and is adapted to an injured person or a disabled person.

[0002]

2. Description of the Related Art In a normal wheelchair of a type which is manually propelled by a user or an attendant, brakes acting on wheels by rotating a lever as braking means are respectively attached to left and right wheels. Further, a special brake that can prevent the wheelchair from running in the reverse direction, and a mechanism that prevents the wheels from rotating in the reverse direction while the vehicle is stopped by a slope or the like have been proposed.

[0003]

When climbing a hill with a wheelchair, a rearward component along the slope acts in proportion to the total weight of the wheelchair including the load according to the slope. Because of this, extra power is required rather than a flat road, and the caregiver has a hard time.However, especially when the user himself is on a wheelchair and climbs a hill, the wheel of the wheelchair is used by utilizing the inertia force of the wheelchair. You must keep the drive wheel spinning quickly with both hands before stopping. Therefore, while traveling on a long slope or a steep ascending slope, the driver must travel while resting.If the vehicle stops on the slope, it is necessary to support the drive wheels even when the vehicle is stopped or to have an attendant hold the steering wheel. If you do so, you may run in a wheelchair.

[0004] In the case of taking a break by applying a normal brake acting on the wheels by turning a lever provided on each of the left and right wheels in the middle of a hill, the driver must first use both hands to drive wheels. Support and stop the left and right wheels, hold one drive wheel with one hand, quickly grab the other hand from the drive wheel to the brake lever, apply the brake to the other wheel, and then follow the same procedure Apply the brake to the other wheel. However, the wheels are released from the time when the drive wheels are released to the time when the brake is started by pulling the lever. Therefore, the wheel starts to reverse, and the wheelchair rotates (turns around) about the contact point with the road on one of the stopped wheels. Depending on the slope and rotation angle of the slope, the balance may be lost and the wheelchair may even fall. When the wheelchair is moved forward again, the same rotational force is generated when the brakes are alternately released, which is extremely dangerous.

[0005] In order to improve the above-mentioned problems when climbing a hill using a wheelchair, various special brakes and means for preventing reverse rotation of the wheels have been proposed, but all of the conventional techniques have complicated structures. Many of the injured, sick, or elderly caregivers are inconvenient. The present invention improves on such disadvantages in the prior art, and uses a commercially-available general-purpose industrial product, and has a simple structure in which the support plate and the attachment combine these components while allowing the user to use a drive wheel. It is an object of the present invention to provide a safe wheelchair reverse running prevention mechanism that is easy for anyone to operate and that does not inadvertently turn the wheels even when the hand is released from the hand or the caretaker does not hold the handle.

[0006]

In order to achieve the above object, in the wheelchair reverse running prevention mechanism of the present invention, the one-way pulley rotating only in the forward direction is set to a position where the operation of the brakes on the left and right wheels is not hindered. , Each of which is detachably mounted.

To attach the one-way pulley detachably to the left and right wheels, one end of the driving link and one end of the driven link are attached to both ends of the stationary link so as to reciprocate, respectively, and the other end of the driving link and the driven link are connected. The joint at the other end of the driving link in the plane four-link mechanism connected with the other end of the driven link by an intermediate link facing the stationary link tightens the joint at a position past the expected point, thereby reducing the reaction force applied to the extended end of the driven link. It is effective to attach the one-way pulley at a position where the operation of the brake is not hindered via a toggle clamp configured to be able to compete.

[0008] Further, a toggle clamp having a one-way pulley incorporated therein may be attached via another screw and nut to a support plate which is easily attached to a part of the vehicle body with a screw and a nut.

Further, it is preferable to form a groove for preventing slip on the outer periphery of the one-way pulley.

[0010] A one-way pulley may be fitted with a tire having a large coefficient of friction.

[0011]

When a user rides on a wheelchair having a reverse running prevention mechanism configured as described above and climbs a hill, one-way pulleys that rotate only in the forward direction (forward direction) are respectively attached to the left and right wheels. Place it in advance by pressing. With this arrangement, the left and right wheels do not reverse due to the frictional force of the one-way pulley even if the user releases one or both hands from the driving wheels at the same time, or the attendant does not hold the handle, and the wheelchair is Stop at that position.

In the case where it is necessary to apply a brake to the other wheel by holding one drive wheel with one hand and changing the other hand from the drive wheel to a brake lever while holding one drive wheel as described in [0004]. However, the wheel on the side where the hand is released from the drive wheel is subjected to the frictional force of the one-way pulley and the wheel does not reverse, so that the wheelchair does not rotate around the contact point of one wheel with the road as an axis .

One end of the driving link and one end of the driven link are attached to both ends of the stationary link so as to swing back and forth, and the other end of the driving link and the other end of the driven link are connected by an intermediate link facing the stationary link. Plane 4
If a one-way pulley is attached to the extended end of the driven link in the toggle clamp using the link mechanism, the one-way pulley can be attached to and detachably attached to the left and right wheels by rotating the driving link by each lever. Can be.

In addition, the toggle clamp described in the preceding paragraph is configured so that the joint (the even-numbered point B) at the other end of the driving link can be tightened to a position past the expected point. When a one-way pulley is mounted on each wheel, even if a reaction force of the wheel is applied to the one-way pulley, a force in the opposite direction acts on the driven link when the one-way pulley is mounted, so the one-way pulley opposes the reaction force of the wheel. Thus, a sufficient frictional force can be maintained.

Although the operation of the planar four-link mechanism is well known,
As a typical example, FIG. 4 shows a double lever link row in which the link 5 facing the intermediate link 8 which is the shortest link is fixed, and its configuration and movement will be briefly described. The two lever link rows include a driving link 6 connected to one end of a stationary link 5 via a rotating pair (hereinafter, sometimes abbreviated as a joint) A, and a coupling B at the other end of the link 6. And the other end of the driven link 7 having one end fixed to a joint D at the other end of the stationary link 5 via a joint C to the other end of the intermediate link 8. Things. By rotating the driving link 6 having one end fixed thereto and pushing the joint B at the top of the cross in a direction perpendicular to the driving link 8, the other end C of the intermediate link 8 becomes the driving link. While moving toward the extension of 6, approaching a straight line. Joint B at the other end of the driving link 6 which is fixed to one end, beyond the straight line A, B _3, C _3, the driven link 7 and the intermediate link 8 reaches B ₄ points overlapping, folding the opposite lateral times . During this time, the joint C at the other end of the driven link 7 is C
Turned back at ₃ Back to _{C 4} points. That is, in the two lever link rows having the rotation pairs A, B, C, and D composed of four links, as shown in FIG.
Driving link 6 and driven link 7 on both sides of fixed link 5
Only swings back and forth. At the point C, the force in the linear direction, which is significantly doubled than the force pressing the point B, acts. As shown, B
If the point comes to B ₁ , B ₂ , B ₃ , B _{4, the} point C comes to C ₁ , C ₂ , C ₃ , C ₄ . Point B, because it can be moved from _three points B in the direction of the well B ₄ points in the direction of the _two points B, B ₃ points are change point, C ₁ if Kaware is driving link
The point is also a thought point. Is joint B at the other end of the drive link 8, if the past change point B ₃ position, the follower link 7
Be subjected to reaction force, B point not go back to just B ₂ is pressed towards the B _4. The toggle clamp 9 can exert a predetermined tightening pressure on the extended end of the driven link 7 by utilizing the operation of the flat four-link mechanism.

Next, the present invention provides a "wheelchair reverse running prevention mechanism".
As another preferred example, a reciprocating rocking motion similar to the two lever link rows is performed, but the driving link 6 and the driven link 7 intersect, and the ratio of the length of each link is different from that of the above example. Spiral torsion spring T and stopper S using 4-link mechanism
_Among the toggle clamps of the type in which the range of movement is regulated by ₁ , _{2 and the} like (the driving link 6 is a generic type of toggle clamp of the Japanese type and the intermediate link 8 is a folding clamp),
The movement of the reverse running prevention mechanism using the lower pressure toggle clamp,
This will be described with reference to FIG. In this example, the rotating pairs A, B,
C, if 5 the stationary link of the link columns with the D, if the point B comes from _{B 1} initial points _{B 2,} B 3, _{B 4} points, C
The points come at C ₁ , C ₂ , C ₃ and C ₄ points. In this case B
Points can be moved from B ₃ points point C comes on a line which overlaps with the driving link 6 in the direction of the well B ₄ points in the direction of the _two points B. Therefore, B ₃ is a conceivable point, and B
I place ₄ points provided stopper S ₂ as point B is stopped, even point B takes the reaction force P to the driven link 7 does not return toward the B _2. (In this case, the driven link 7 may be regarded as the driving link.) In this example, the driving link 6 is used.
Since the driven link 7 and the stationary link 5 are shorter than those of the above, the driving link 6 and the intermediate link 8 are substantially straight (obtuse angle).
Although not a smaller angle formed between the driving link 6 and the intermediate link 8 in B _4, it is possible to exert a large clamping pressure.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings.

[0018]

Embodiment 1 In FIGS.
In the forward direction (rightward rotation (arrow a) opposite to the wheel 2 on the left side of the wheelchair 20 shown in FIGS. 1 and 5 and leftward rotation (arrow a) on the right side of the wheelchair 20). One-way pulley. Reference numerals 4 and 4 denote ordinary brakes of the type in which brake pieces bite into the left and right wheels 2 and 3 by turning operation of a toggle clamp lever. However, since these brakes are the same as the "prior art", FIG. The detailed description is omitted by showing the released state with a solid line and the state where the wheel 2 is tightened as braking means with a two-dot chain line. Therefore, first, as shown in FIG.
A method of mounting the wheelchair by pressing it against the outer peripheral surface of the left wheel 2 of the wheelchair 20 will be described. As shown in FIGS. 2 and 5, initially, the other end of the driving link 6 to _a point B by the action of the helical torsion spring T and the stopper S _1, the other end of the driven link 7 C
_Since it is at _one point, the one-way pulley 1 is stopped at a position away from the wheel 2 (the left side in FIG. 5). By rotating the lever 21 of the toggle clamp 9 on the left side in the downward pressure direction (arrow C), the driving link 6 whose one end is pinned to one end of the stationary link 5 by the joint A is swung. .
For the configuration and operation of the flat four-link mechanism, see “001”.
6), the other end of the driving link 6 has a joint B
And one end of the intermediate link 8 is connected via a joint C, and the other end is connected to the other end of the driven link 7 pinned to a joint D which is the other end of the stationary link 5 via a joint C. Therefore, the attachment 40 is attached to the extension end of the driven link 7.
, The one-way pulley 1 attached via the sway swings in a direction (arrow d) approaching the left wheel 2.

As shown in FIGS. 1 and 5, the joint B at the other end of the driving link 6 is positioned at a position B ₄ slightly past the thought point B ₃ (the other end C _{4 of the} intermediate link 8 is connected to the driving link 6). At a position above the line connecting both ends A and B ₄ of the motor 6), the driving link 6 is stopped by the stopper S ₂ , and the one-way pulley 1 presses the outer peripheral surface of the left wheel 2. 5 and "0016" as described in the section, because the point B has passed the change point B ₃ (B ₄ points), also takes the reaction force P of the wheel 2 in the one-way pulley 1 i.e. the follower link 7, B the point is not go back in the direction of the B _2. Drive link 6 and intermediate link 8
Is small, the one-way pulley 1 can clamp the outer peripheral surface of the wheel 2 with such a force that the wheel 2 does not slip due to the backward component force based on the slope of the slope.

Since the one-way pulley 1 rotates only in the forward direction (arrow A) as described in the section "0018", the left wheel 2 tightened by the one-way pulley 1 moves in the forward direction (arrow B), and when climbing a hill, the user releases his / her hand from the drive wheel 22 for the wheel 2 attached to the outside of the wheel 2, or the caretaker does not hold the handle 23. However, the wheels 2 do not reverse. Further, even if the left driving wheel 22 is released with the brake 4 applied to the right wheel 3, the left wheel 2
Is held by the frictional force of the one-way pulley 1, which can rotate only in the forward direction, without being reversed, and is held at that position. Therefore, there is no possibility that the wheelchair will rotate around the contact point between one of the stopped wheels and the road. As described above, the "wheelchair reverse running prevention mechanism" on the left side has been mainly described. As shown in FIGS. 2 and 3, this mechanism has a symmetric structure (the rotation direction of the one-way pulley 1 is also reverse). One set is attached to each of the left and right sides. Next, the lever 21 of the right toggle clamp 9 is
By turning in the downward pressure direction (arrow C), the right one-way pulley 1 is swung in a direction approaching the right wheel 3 (arrow d), and is pressed against the outer peripheral surface of the right wheel 3 for mounting. The operation, operation, and effect are the same as those on the left side, and thus detailed description is omitted.

In this embodiment, the one-way pulley 1,
A device has been devised so that the "wheelchair reverse running prevention mechanism" composed of a pair of the wheelchair 1 and the toggle clamps 9, 9 can be easily mounted without modifying the wheelchair 20, so the configuration and simple mounting means will be described. . In order to mount the brakes 4 and 4 on the wheelchair 20, brake mounting plates 26 and 26 are provided on a part of the vehicle body 25. In this example, the brake mounting plates 26, 2 welded to the vehicle body 25
The left and right "wheelchair reverse running prevention mechanisms" were attached to the inside of each of them by using No. 6. As clearly shown in FIG. 2, inverted L-shaped support plates 28, 28 in which two holes are drilled at the same intervals as the long holes 27, 27 for mounting the brake on the brake mounting plates 26, 26 are previously formed and placed. . First, the brakes 4 and 4 are placed outside the brake mounting plates 26 and 26,
Inside the support plates 28, 28, the same screws 10, 10
And the nuts 11, 11... Are temporarily tightened at the same time, and while the brakes 4, 4 are moved along the elongated holes 27, 27, the tightening pressure of the brakes 4, that is, the tightening position is adjusted.

When the tightening positions of the brakes 4, 4 are determined in this manner, the nuts 1 are attached to the screws 10, 10,.
The support plates 28, 28 are fixed in this position by tightening 1, 11,. At the lower part of the support plates 28, 28, two holes slightly larger than the toggle clamp mounting holes are provided at the same intervals as the toggle clamp mounting holes so that the toggle clamps 9, 9 are located at positions where the operation of the brakes 4, 4 is not hindered in advance. Is pierced,
Align the mounting holes of the toggle clamps 9, 9 with these holes, and use the other screws 31, 31 and nuts 32, 32.
If the toggle clamps 9, 9 with the one-way pulleys 1, 1 are mounted at this position, the toggle clamps 9, 9 and the one-way pulleys 1, 1 can be easily mounted at predetermined positions.

Reference numerals 33, 33 denote position adjusters for finely adjusting the tightening pressure. When the one-way pulleys 1, 1 slide or the tightening pressure on the wheels 2, 3 is too strong, the screws 31, 31,. And the nuts 32, 32,... Are loosened to adjust the tightening pressure position, that is, the tightening pressure with the position adjuster, and then retightened.

The commercially available one-way pulleys 1, 1 have a smooth surface and a low coefficient of friction for use as braking wheels. For this reason, in this embodiment, FIG.
As shown in FIG. 2, one-way pulleys 1, 1 having a rubber tire 34 having a large friction coefficient fitted on the outer periphery thereof were used.

[0025]

Second Embodiment Although not shown, non-slip grooves (tread patterns) cut into various shapes are provided on the surface of the tire to increase the friction coefficient on the surface of the one-way pulleys 1, 1. The tightening pressure on the wheels 2 and 3 can be reduced.

[0026]

Embodiment 3 The toggle clamp is not limited to the lower pressure type as exemplified in "Embodiment 1", but operates in the opposite direction, that is, if the lever 21 is lifted, the driven link is driven. It is also possible to use one in which 7 is tightened. Toggle clamps and one-way pulleys are sold in various forms and sizes as general-purpose industrial products. For this reason, a combination of a toggle clamp and a one-way pulley that can be detachably attached to positions that do not hinder the operation of the brakes 4 and 4 on the left and right wheels 2 and 3 may be selected according to various wheelchairs. However, when practicing the present invention, it is preferable to set the operating direction of the lever 21 in order to avoid confusion.

[0027]

Embodiment 4 Further, the support plate 28,
At the bottom of 28, two holes are drilled at the same interval as the mounting hole of the toggle clamp, and another screw 31, 31,.
The structure in which the toggle clamps 9, 9 with the one-way pulleys 1, 1 incorporated therein are attached to the one-way pulleys 1, 1 with the nuts 32, 32,. May be welded and placed.

[0028]

Fifth Embodiment The preferred embodiment of the present invention in which the left and right wheels 2, 3 are detachably attached to the wheels 1, 3 via the toggle clamps 9, 9 has been described above. In the “mechanism”, the use of the toggle clamps 9 is not an essential requirement. For example, the one-way pulleys 1 and 1 are respectively placed at positions where the operation of brakes (not shown) of the left and right wheels 2 and 3 is not hindered by using a "twisted torsion spring feed lever" used for mounting / removing a bicycle generator or the like. It can be attached and detached freely. As shown only in the main part of the mechanism on the left side in FIGS. 6 and 7, a round shaft 44 in which a lever 43 is planted in a radial direction is inserted into a helical torsion spring 42 having one end 41 fixed, and the spring is inserted. The other end of 42 is fixed to the round shaft 44. When the lever 21 ′ having the fulcrum 45 pivoted to the support plate 28 ′ is pivoted in the direction of the arrow E and the lever 43 is pressed, the attachment 4 attached to the round shaft 44 is pressed.
0 'is swung in the direction of the arrow, and the one-way pulley 1,
1 can be mounted on the surface of the left wheel 2.

In this example, the tightening pressure of the one-way pulleys 1 and 1 on the wheels 2 and 3 was relatively large, and the wheelchairs used were hollow wheels 2 and 3 on which air pressure was applied. 34, omitted from FIGS.
By forming 36 non-slip grooves 15 parallel to the shaft on the surface of the metal one-way pulleys 1 and 1 shown in FIG.

[0030]

Embodiment 6 Although various embodiments of the present invention have been described above, the present invention can be embodied in various different embodiments within the scope described in the claims.

[0031]

Since the present invention is configured as described above, it has the following effects.

As long as the one-way pulleys are mounted on the left and right wheels, both wheels are constantly under a tightening pressure.
None of the wheels will reverse. For this reason, only the brakes that act on the wheels by the turning operation of the lever described in the section of the “prior art” are used by a wheelchair user on an uphill slope as in a normal wheelchair attached to each of the left and right wheels. It is not necessary to hold the drive wheels while resting on the way. Also, even if you release your hands from the drive wheel due to fatigue, erroneous operation, or the caregiver does not hold the handle,
There is no danger that the wheelchair will reverse. Therefore, the user only needs to rotate the drive wheels at a pace that matches his or her physical strength,
Even if you do not brake each time you take a break because you are tired, if you stop the rotation of the drive wheel, the wheelchair will stop at that position. Even when the caregiver presses the handle to operate, there is no danger of the wheelchair running backward during stoppage, so there is no need to keep the handle tensed until rest and the body and mind are comfortable.

When taking a break in the middle of a long uphill, when the brakes are applied to the left and right wheels one by one, the one-way pulley tightening pressure is also applied to the wheel that is released from the drive wheel. Does not reverse. Similarly,
Even if the brakes are alternately released when moving forward again, the wheel on the side where the brake is not applied does not reverse. Therefore, there is no danger that the wheelchair will rotate around the point of contact with the road on one of the stopped wheels, and there is no danger of the wheelchair falling over.

The present invention also provides a "wheelchair reverse running prevention mechanism".
Is a one-touch operation that only lowers or raises the levers of the left and right toggle clamps before climbing a hill. If one-way pulleys are mounted on the left and right wheels, there is no need to perform complicated operations on the way. Therefore, anyone can operate easily.

Further, the support plate and the attachment of the one-way pulley are designed and manufactured according to the structure and dimensions of each wheelchair so that the one-way pulley can be detachably attached to a position where the operation of the brake is not hindered. If this is done, it is a simple mechanism combining only a commercially available toggle clamp and a one-way pulley, so that all wheelchairs can be easily attached without any modification. Furthermore, if a toggle plate with a built-in one-way pulley can be attached via another screw and nut to a support plate that is easily attached to a part of the vehicle body with screws and nuts, the wheelchair The attachment to the device becomes easier and versatility is increased.

In addition, since the mechanism is small, it is attached to a wheelchair and used when the wheelchair is used on a flat surface, when the vehicle is retracted, or when there is no need to use the "wheelchair reverse running prevention mechanism" of the present invention. If the one-way pulley is detached from the left and right wheels by operating the lever, the operation and storage of the wheelchair will not be hindered.

[Brief description of the drawings]

FIG. 1 is a side view showing a main part of a most preferred embodiment of the present invention “wheelchair reverse running prevention mechanism”.

2 shows the opposite side (right side) from that shown in FIG. 1 in order to show the inactive state in which the one-way pulley has been removed from the wheels.
Is a side view of the "reverse running prevention mechanism" attached to the vehicle viewed from the inside of the wheelchair, and the brake is omitted.

FIG. 3 is a sketch showing an example of a wheelchair in which the “wheelchair reverse running prevention mechanism” of the present invention is attached to left and right wheels.

FIG. 4 is an explanatory view showing the operation of a double lever link row composed of a plane four link mechanism.

FIG. 5 is an explanatory diagram showing the operation of the “wheelchair reverse running prevention mechanism” exemplified in FIGS. 1 to 3;

FIG. 6 is a side view showing a main part of a different embodiment of the "wheelchair reverse running prevention mechanism" of the present invention in a released state.

FIG. 7 is a plan view of the mechanism shown in FIG. 7;

[Explanation of symbols]

Reference Signs List 1 one-way pulley 2 left wheel 3 right wheel 4 brake 5 stationary link 6 driving link 7 driven link 8 intermediate link 9 toggle clamp 10 screw 11 nut 15 one-way pulley 1 non-slip groove 16 one-way pulley 1 tire 28 support plate 31 Mounting screw for toggle clamp 9 32 Mounting nut for toggle clamp 9 A, B, C, D Rotational pair of plane 4-link mechanism B ₃ , C ₁

Continued on the front page (72) Inventor Tomomi Ohno 7-23, Timber Konan, Hatsukaichi, Hiroshima Pref.

Claims (5)

[Claims] 1. A reverse running prevention mechanism for a wheelchair, wherein a one-way pulley that rotates only in a forward direction is detachably attached to a position that does not hinder the operation of brakes on left and right wheels. 2. One end of a driving link and one end of a driven link are attached to both ends of a stationary link so as to reciprocate, respectively, and the other end of the driving link and the other end of the driven link are connected by an intermediate link facing the stationary link. A joint at the other end of the driving link in the flat four-link mechanism is provided with a toggle clamp configured so as to be able to resist a reaction force applied to the extended end of the driven link by tightening at a position past the thought point. The reverse running prevention mechanism for a wheelchair according to claim 1, wherein a one-way pulley is detachably attached to a wheel of the left cloth. 3. A toggle clamp incorporating a one-way pulley is attached via another screw and nut to a support plate which is easily attached to a part of the vehicle body with a screw and a nut. 2) The wheelchair reverse running prevention mechanism according to the item [2]. 4. The wheelchair reverse running prevention mechanism according to claim 2, wherein an anti-slip groove is formed in the outer periphery of the one-way pulley. 5. The wheelchair reverse running prevention mechanism according to claim 2, wherein a tire having a large coefficient of friction is fitted to the one-way pulley.