JP3683952B2 - Casters with turning control and braking mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a caster in which a frame on which a wheel is attached is horizontally swiveled with respect to a mounting shaft. The caster has both a turn restricting mechanism for restricting the horizontal turn and a braking mechanism for stopping the turn of the wheel, and the operation is unified. The present invention relates to a caster with a turning restriction / braking mechanism and a wheelchair using the caster, particularly a wheelchair that is excellent in use around water.
[0002]
[Prior art]
A caster in which a frame with a wheel attached to an attachment shaft rotates horizontally is used in various transport devices such as hand-carried small carts, shopping carts, and wheelchairs. In order to ensure safety, a braking mechanism is usually provided. This caster with a brake mechanism is such that a brake shoe that presses a wheel is linked to an L-shaped brake handle that is attached to the outside of the wheel, and the wheel is braked and released by operating the foot from the same direction (Japanese Patent Laid-Open No. 4). -123902), the brake body that is biased downward through the mounting shaft and the wheel are separated and contacted by a lever located away from the caster to brake and release the wheel (Japanese Patent Laid-Open No. 62) -77202), connecting a wire penetrating the mounting shaft to a brake shoe biased to press the wheel, and operating this wire to brake and release the wheel (Japanese Patent Laid-Open No. 7-32807), etc. There is.
[0003]
In addition, in order to make it easy to go in and out of a narrow place and to change direction, in wheelchairs, etc., all four wheels are configured with casters that can be turned horizontally. In this case, in order to ensure straightness of the wheelchairs, In some cases, a turning restriction mechanism may be provided. The conventional turning restriction mechanism works simultaneously with the braking mechanism. For example, when the foot lever is rotated, the insertion shaft portion of the foot lever pivoted on the leg is rotated, and the elasticity of the insertion shaft portion is rotated. When the plate is locked in the locking groove of the fixed base plate and is in contact with the outer side of the wheel, turning movement and running rotation are stopped (Act No. 4-961), when the lock pedal reaches the lock position , The locking surface of the lock plate is the brake pressure contact around the wheel and the rotation lock claw of the lock plate engages with the lock receiving groove recessed in the lower end surface of the pivot shaft to lock the rotation and rolling (No. 56-32323).
[0004]
[Problems to be solved by the invention]
As can be seen from the above, the conventional caster only stops the rotation of the wheel or stops the rotation of the wheel and simultaneously controls the turning, and cannot be run while restricting the turning. In addition, when looking at the operability of the caster having a turning restriction / braking mechanism, a lever for operating both mechanisms is provided on the caster, and the lever must be operated with a foot, and the caster mounting position is deep, The operability of the lever was bad, such as when the caster turned. In particular, in the case of a wheelchair, a caster with a turning control / braking mechanism that operates with high operability and reliability is preferable, and conventional casters cannot meet this requirement.
[0005]
The wheelchair is a tool to assist the movement of sick people and injured people who are unable to walk on their own, and is expected to be used everywhere in daily life, and can freely decide the direction of travel or change direction while staying in place It is also necessary to plan. When a wheelchair user repeatedly moves and stops in a small place, it is difficult to change the direction of the wheel freely, and sometimes it is desired to brake the wheel with the caster directed in a predetermined direction. There are many places where such use of wheelchairs is restricted, but the surroundings of water such as a washroom, a toilet, a bathroom, etc. in a narrow space can be mentioned.
[0006]
The direction of the caster changes when entering or leaving a narrow space, especially when entering or leaving the toilet, and it may be dangerous due to unexpected contact with the wall surface or pottery (toilet). In addition, because the toilet is small, it is not possible to drive the wheelchair sufficiently, and if it is difficult to change the direction in the toilet room, or if the direction of the wheel changes during use of the toilet, it will not be possible to leave the toilet by itself It is also possible. There is no inconvenience due to the size of the room in the bathroom compared to the toilet, but the wheel turns on its own due to the wet floor and the wheelchair cannot be operated as the user thinks. It may also impose excessive effort on the person. In addition, there are usually many small steps found in door frames, sills, power cords, etc., and there is an opportunity for caregivers or guardians to lift the front wheels slightly around the wheelchair and try to get over the steps. Although it frequently occurs, if the center of gravity of the wheelchair is displaced rearward beyond the rear wheel at this time, the rear wheel turns freely without permission, and there is a danger that the wheelchair cannot be moved or that the wheelchair falls down.
[0007]
Therefore, on the assumption that the wheelchair is used around water or in a house, the structure of the caster is considered, and the structure of the caster having both a braking mechanism and a turning restriction mechanism that operates independently of the braking mechanism and both We studied the operation method of the mechanism, and decided to apply it to wheelchairs and other small luggage carriers and shopping carts.
[0008]
[Means for Solving the Problems]
What has been developed as a result of the study is a caster that has a mounting shaft at the top of the frame that is attached to the wheel, and the frame rotates horizontally with respect to the mounting shaft. A turning restriction mechanism for restricting and a braking mechanism for stopping the rotation of the wheel are provided in the frame body, and either or both of the turning restriction mechanism and the braking mechanism are set according to the length of pulling or returning the wire penetrating the mounting shaft. It is a caster with a turning restriction / braking mechanism characterized by working. This caster is characterized in that the turning restriction mechanism and the braking mechanism work individually or in conjunction by pulling or returning the wire.
[0009]
For example, the turning restricting mechanism connects the wire to the operation plate that is pivotally attached to the inside of the frame, and pulls or returns the wire to the engagement receiving portion provided on the attachment shaft. Engagement restricts horizontal rotation of the frame relative to the mounting shaft, and the braking mechanism further presses the operation plate by pulling or returning the wire from a state where the engagement fitting portion engages with the engagement receiving portion. The part is pressed to stop this wheel. That is, either or both of the turning restriction mechanism and the braking mechanism are made to work on the same wire depending on the difference in the amount of pulling or returning.
[0010]
The operation plate is a member that swings up and down. For example, when a rocking shaft is provided near the middle of the operation plate, an engaging fitting part that protrudes upward at one end, a pressing part downward at the other end, and an outer periphery of the mounting shaft A gear-shaped engagement receiving portion is provided, and a wire is connected between the engagement fitting portion and the swing shaft. If the distance between the engagement fitting part and the engagement receiving part is made shorter than the distance between the wheel and the pressing part, when the operation plate is swung by pulling the wire, the engagement fitting part first becomes the gear of the engagement receiving part. The pressing portion can be brought into a state where the wheel does not press the wheel, that is, only the turning restricting mechanism is operated. Next, when the wire is pulled from the above state and the operation plate is further swung, the pressing portion comes into pressure contact with the wheel from above, and the braking mechanism can be operated in addition to the turning restriction mechanism. The pressing part uses the principle of the lever with the swinging shaft as a fulcrum, the wire connection point as the force point, and the pressing part as the action point, and the pulling force of the wire (length from the swinging shaft to the wire connection point / pressing part Since the wheel is pressed with a force amplified at a ratio of the length from the to the swinging shaft), a higher braking force can be obtained than when the wheel is pressed by urging with a spring or the like. It can be adjusted freely by changing.
[0011]
In addition, when a swing shaft is provided at one end of the operation plate and the operation is swung so as to move away from the wheel by pulling the wire, the pressing portion made of the brake shoe is pressed against the inside of the wheel from below. If the distance between the engagement fitting part and the engagement receiving part is shorter than the distance between the wheel and the pressing part, the turning restriction mechanism is first set in the same manner as described above. After working, the braking mechanism can be activated. In the case of reversing the order in which the turning restriction mechanism and the braking mechanism are operated, the distance between the engagement fitting portion and the engagement receiving portion may be made longer than the distance between the wheel and the pressing portion. When the two are operated simultaneously, the distance between the engagement fitting portion and the engagement receiving portion may be set equal to the distance between the wheel and the pressing portion.
[0012]
When the above caster is used in a wheelchair, two levers are attached in series to the wire of this caster, and one lever can pull or return the wire to such an extent that either the turning restriction mechanism or the braking mechanism works. The other lever may be configured such that the wire can be pulled or returned to such an extent that the turning restriction / braking mechanism works together. Note that the wire can be pulled or returned in two stages with a single lever. However, by dividing the lever into two bodies and assigning a mechanism that works to each, the lever corresponding to the combination of each mechanism can be attached to the wheelchair where it is most easily operated.
[0013]
In wheelchairs used around water, especially in narrow toilets, even if there is a lever in an easy-to-operate place until entering the toilet, it is difficult to use when entering the toilet, and in some cases it cannot be used. There is also. Therefore, in the wheelchair of the present invention, the caregiver or guardian regulates the traveling direction of the wheelchair and guides the wheelchair to the toilet, once the wheelchair is positioned on the toilet seat while turning off the turning restriction of all casters, For example, a lever corresponding to the turning control mechanism is provided on the operation handle of the wheelchair for the convenience of a caregiver or a guardian, and the turning control / braking is controlled. For the levers that comply with the regulations, a lever that activates the turning restriction / braking mechanism should be installed near the armrest so that not only the caregiver or the guardian but also the wheelchair user can operate the lever in the toilet room. .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the caster and the wheelchair of the present invention will be described by taking a wheelchair for surrounding water as an example. FIG. 1 is a perspective view showing the entire wheelchair 1, and FIG. 2 is a side view showing a movable armrest 2. In the wheelchair 1 of this example, the lever that operates the turning control mechanism or the braking mechanism of the caster is divided into a direction control lever that uses only the turning control mechanism, a braking lever that uses the turning control mechanism and the braking mechanism at the same time, and the direction control lever 3 Is attached to the operation handle 4 of the wheelchair, and the brake lever 5 is arranged below the rotation shaft 6 of the armrest 2.
[0015]
As shown in FIG. 1, the wheelchair 1 of the present example has an operation handle 4 at the upper end of an oval frame 7, 8 that is crushed in the left-right direction of the wheelchair, and avoids a vertically long opening 10. There is no member between the frames 7 and 8 except that a support member (not shown) is installed between the frames 7 and 8, and the wheelchair 1 is moved into the toilet room (usually a Western style toilet) to place the seat. It can be located above the toilet bowl, so that the user of the wheelchair can use it directly from the opening to the toilet bowl. Since the frames 7 and 8 having an elliptical cross section have strength and can be narrower than a round pipe, for example, a toilet seat and toilet bowl that cannot be accessed with a round pipe having the same strength in a toilet bowl equipped with a flush toilet seat. The oval frame can be advanced to the gap between the wheelchair and the wheelchair can be completely positioned above the toilet. There are a total of four casters 11 and 12 before and after each of the frames 7 and 8, but the caster 12 of the present invention is the rear two, and the wire 13 from the caster 12 extends upward along the frames 7 and 8, A brake lever 5 is disposed below the pivot shaft 6 of the armrest 2, and a direction regulating lever 3 is disposed on the operation handle 4.
[0016]
As described above, the wheelchair 1 of this example can go to the toilet while the user is seated, and the armrest 2 can be rotated upward, or the footrest 14 can be opened to the left and right to We are trying to make getting on and off as easy as possible. Further, as shown in FIG. 2, the armrest 2 has a structure in which the armrest 2 is fitted into the rotating shaft 6 having two latching angles 15 in the circumferential direction, so that only within a necessary range. It regulates to turn at. By providing the restriction of the rotation range in the rotation shaft 6 in this way, there is a risk of a finger being caught between this member and the rotating armrest that occurs when a member that restricts the rotation range is attached to the outside. It will disappear.
[0017]
FIG. 3 is a cross-sectional view of the caster 12 in a state where the turning restriction / braking mechanism is not working, and FIG. 4 is a cross-sectional view showing the direction restriction lever 3 and the brake lever 5 in the above state. As shown in the figure, a mounting shaft 19 is connected to the top of the frame 17 on which the wheel 16 is pivotally attached via a ball bearing 18 protected by a packing 31, and the mounting shaft 19 is screwed to the frame 7 (or 8). Then, when attached to the wheelchair 1, the frame body 17 rotates 360 degrees relative to the attachment shaft 19. The operation plate 20 has a plate-like shape having an engagement fitting portion 21 (left end in FIG. 3) projecting upward at one end and a pressing portion 22 (right end in FIG. 3) made of a wide brake shoe inflated downward at the other end. A member (see FIG. 5 (a perspective view showing the operation plate 20 with the engagement fitting portion 21 fitted in the engagement receiving portion 23)), between the lower end of the mounting shaft 19 in the frame 17 and the wheel 16 The swivel spring 24 urges the engagement fitting portion 21 to be pushed downward (in the left rotation direction in FIG. 3). The wire 13 is connected between the engagement fitting portion 21 and the swing shaft 25 so that the engagement fitting portion 21 can be pulled up (right rotation in FIG. 3).
[0018]
The turning restriction mechanism includes an engagement receiving portion 23 attached to the lower end of the attachment shaft 19 and an engagement fitting portion 21 of the operation plate 20. As shown in FIG. 5, the engagement receiving portion 23 is formed of a gear-shaped member having a concave portion 26 radially, and rotates horizontally with respect to the frame body 17 integrally with the mounting shaft 19. The engagement fitting portion 21 is lifted when the operation plate 20 is swung by the wire 13 and is fitted into the concave portion 26 of the engagement receiving portion 23 to restrict the turning of the frame body 17 relative to the mounting shaft 19. In this way, the directionality of the wheel 16 is fixed. The braking mechanism is performed by the pressing portion 22 of the operation plate 20, and the pressing portion 22 makes surface contact with pressure against the wheel 16 by further swinging the operation plate 20 with the wire 13 from the previous state. The wheel 16 stops rotating.
[0019]
As shown in FIG. 4, the direction regulating lever 3 and the braking lever 5 have substantially the same structure, but the shape of the cam portions 27 and 28 is slightly different so that the latching portion 29 sandwiched between the wires 13 is obtained. The amount of push up is changed. That is, the direction restricting lever 3 slightly lifts the latching portion 29 with the cam portion 27 so that the operation plate 20 is swung to such an extent that the engagement fitting portion 21 fits into the engagement receiving portion 23. The pulling / braking lever 5 pulls the wire 13 by further lifting the latching portion 29 so that the operation plate 20 is swung to such an extent that the pressing portion 22 presses the wheel 16. Note that the latching portion 29 is biased in the direction to pull down the wire 13 by the coil spring 30. If the direction regulating lever 5 (or the brake lever 7) is returned to the initial position, the latching portion 29 is pushed up. Only the wire 13 is pushed down, and the operation plate 20 is restored step by step.
[0020]
In the wheelchair 1 of the present example, since the levers 3 and 5 are both returned to the initial position in the initial state, the operation plate 20 naturally does not swing, and the engagement fitting portion 21 can be seen as shown in FIG. Is from the engagement receiving portion 23 and the pressing portion 22 is separated from the wheel 16. Moreover, the latching | locking part of each lever 3 and 5 exists in the state pushed down by each coil spring 30, as FIG. 4 shows. In addition, although the state where each lever is tilted can be set to the initial state, the lever is usually in the way of the wheelchair operation, so normally it is attached to the frame as in this example, and each It is preferable to tilt the lever so that the turning restricting mechanism or the braking mechanism is activated.
[0021]
FIG. 6 is a cross-sectional view of the caster 12 in a state where the turning restricting mechanism is working and the braking mechanism is not working, and FIG. 7 is a cross-sectional view in a state where the direction restricting lever 3 is tilted and the braking lever 5 is left in the initial position. . By tilting the direction regulating lever 3, as shown in FIG. 7, the cam portion 27 of the lever 3 pushes up the latching portion 29, and the wire 13 is pulled up in accordance with the push-up amount. As described above, the operation plate 20 swings, and the engagement fitting portion 21 is fitted into the recess 26 of the engagement receiving portion 23. However, the operation plate 20 that swings when the wire 13 is pulled up by the direction regulating lever 3 does not press the pressing portion 22 against the wheel 16, and the braking mechanism does not work. The wheelchair 1 of the present example has a step, particularly a small step present in the house, when the wheelchair is moved into or out of a narrow room such as a toilet or when the wheelchair 1 is always advanced in a certain direction. If you want to get over, restrict the direction.
[0022]
FIG. 8 is a cross-sectional view of the caster 12 in a state in which both the turning restriction / braking mechanism is working, and FIG. 9 is a cross-sectional view in a state in which both the direction restriction lever 3 and the braking lever 5 are tilted. As shown in FIG. 9, the cam portion 28 of the brake lever 5 pushes up the latching portion 29 by further tilting the brake lever 5 from the state where the direction regulating lever 3 is tilted, and the wire 13 is further adjusted in accordance with the push-up amount. As shown in FIG. 8, the operation plate 20 is further swung, and the pressing portion 22 is maintained while the engagement fitting portion 21 is fitted in the recess 26 of the engagement receiving portion 23. Press contact with wheel 16. Thus, the caster 12 is subjected to direction regulation and braking, and the wheelchair 1 is stopped. If the braking lever 5 is suddenly tilted without tilting the direction regulating lever 3, the turning regulation / braking mechanism works at once, and the wheelchair 1 stops the caster 12 in a state of being directed in a certain direction. Such control of the wheelchair 1 is used when turning the caster 12 in the direction when the wheelchair 1 enters, considering the case where the wheelchair 1 entered into a narrow room such as a toilet is withdrawn.
[0023]
In the wheelchair of this example, the caregiver or assistant takes the user and takes the wheelchair to the toilet, and the caregiver or assistant enters the narrow room of the toilet while regulating the direction of the wheelchair. It is assumed that the person himself / herself restrains the wheelchair in the toilet room while maintaining the state in which the directionality is regulated. As can be considered from the above description, the direction regulating lever and the braking mechanism lever can be integrated by forming a cam portion having two types of radii. However, when considering the use state of the wheelchair described above, considering the convenience of the caregiver or assistant and the convenience of the user, the direction control lever and the brake lever are separated as in this example, and each wheelchair is further divided. It is better to have a completely different mounting position with respect to.
[0024]
As described above, the caster according to the present invention is provided with a lever for operating the swiveling / braking mechanism apart from the caster to improve the operability of each mechanism, and further, the both mechanisms are incorporated in the frame body, and the ball bearing is provided. Although it is most useful for a wheelchair used around water by protecting with a packing to enhance water tightness, the caster of the present invention can also be used for a parcel carrier, a shopping cart, and the like. In such a small baggage transport vehicle and a shopping cart, it is preferable to integrate both of them rather than separating the direction regulating lever and the braking lever because the operability is improved. In this case, as described above, it may be configured by one lever having cam portions having two types of radii, or two levers having cam portions having different radii may be arranged in parallel so that each lever can be rotated. You may integrate by making the moving shaft the same.
[0025]
【The invention's effect】
The caster of the present invention can improve the feeling of use and safety in consideration of the convenience of both the caregiver or assistant who operates the wheelchair and the user riding in the wheelchair, particularly in a wheelchair used around water.
[0026]
Since the caster itself includes the turning restricting mechanism and the braking mechanism in the frame, the appearance of the caster itself is not greatly changed and can be handled in the same manner as a conventional caster. Further, the frame body can protect both mechanisms from the outside, for example, protection from water splashes around the water. Further, the turning restriction mechanism and the braking mechanism can be operated with a single wire penetrating the mounting shaft, and even when the caster continues to turn 360 degrees, there is an advantage that the wire does not twist or bend. As described above, the caster of the present invention is improved in operability and safety while maintaining the handling of a conventional caster, and is particularly suitable for use in a wheelchair.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an entire wheelchair.
FIG. 2 is a side view showing a movable armrest.
FIG. 3 is a cross-sectional view of a caster in a state where both the turning restriction / braking mechanism are not working.
4 is a cross-sectional view showing a direction regulating lever and a brake lever in the state of FIG. 3;
FIG. 5 is a perspective view showing the operation plate in a state where the engagement fitting portion is fitted into the engagement receiving portion.
FIG. 6 is a cross-sectional view of a caster in a state where a turning restricting mechanism is working and a braking mechanism is not working.
7 is a cross-sectional view showing a direction regulating lever and a brake lever in the state of FIG.
FIG. 8 is a cross-sectional view of the caster in a state where both the turning restriction / braking mechanism are working.
9 is a cross-sectional view showing a direction regulating lever and a brake lever in the state of FIG.
[Explanation of symbols]
1 Wheelchair for around water 3 Direction control lever 4 Operation handle 5 Brake lever
12 Casters of the present invention
13 wires
16 wheels
17 Frame
19 Mounting shaft
20 Operation panel
21 Engagement fitting
22 Pressing part
23 Engagement receiver

Claims (2)

A caster having a mounting shaft at the top of the frame body on which the wheel is pivotally mounted, the frame body horizontally swinging with respect to the mounting shaft, A turning mechanism for stopping the rotation is provided in the frame, and the turning control mechanism connects the wire penetrating the mounting shaft to the operation plate attached to the frame and pulls or returns the wire to the operation plate. The provided engagement fitting portion engages with the engagement receiving portion provided on the attachment shaft to restrict horizontal turning of the frame body with respect to the attachment shaft, and the braking mechanism includes the engagement fitting portion engaged with the engagement reception portion. A caster with a turning restriction / braking mechanism, wherein the pressing portion of the operation plate comes into pressure contact with the wheel to stop the wheel by further pulling or returning the wire from the finished state . Wa becomes attached to lever ear in two bodies in series, one lever can be to the extent that the turn restriction mechanism works back or pulling the wire, the other lever wire to the extent that the turn restriction and braking mechanisms work together The caster with a turning restriction / braking mechanism according to claim 1, which can be pulled or returned.

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