RU2787981C1 - Device that ensures the safety of a wheelchair when lifting - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to the field of mechanical engineering, in particular to devices that ensure the safety of a wheelchair when lifting. The device contains a pair of automatic recoil brakes, two overrunning clutches, a separator with rollers located in its grooves, a control lever, and a parking brake. A pair of automatic recoil brakes is symmetrically mounted on both running wheels. Two overrunning clutches mounted in the main wheel hubs, each of which includes a fixed sprocket, fixed by a lever with the sidecar frame. The separator has the ability to rotate around its axis.

EFFECT: increased safety and easier control during lifting.

3 cl, 4 dwg

Description

The invention relates to controlled devices that provide torque transmission in one direction, with the possibility of disabling this function, and can be used in lifting mechanisms to ensure safety, in wrenches for ease of unscrewing and tightening hard-to-reach threaded connections, in wheeled and tracked vehicles, ensuring the movement of passengers, cargo on the surface when moving uphill (ramp, sidewalk slope, paths in the adjacent territory), and, first of all, to wheelchairs.

The presence of a rolling force when moving up requires not only the creation of an effort by the disabled person to overcome it, but also the need to prevent the wheelchair from rolling back at the moment of transferring hands on the wheel hoop, which creates significant inconvenience, difficulties during movement, and can also cause uncontrolled rolling back with increasing speed, lead to a fall, both for the wheelchair and for the disabled person.

Technical level. As a result of the patent search, the following inventions were selected.

Automatic brake of a vehicle, mainly for moving a person up stairs (RU 2459605 C1, IPC A61G 5/06, published on 08/27/2012), containing levers with support rollers at their free ends, pivotally mounted on the vehicle frame from the side to the front of the vehicle wheels , with the possibility of forced transfer from the non-working, for example, outside the flights of stairs, the upper position to the working, mainly on the flights of stairs, the lower position with the rolling of the rollers on the step or other supporting surface next to the wheels and the subsequent breakdown under the action of at least one's own forces of gravity and hovering over a lower level or other supporting surface of a lower level, and spring-loaded with the possibility of fixing in its non-working upper position by the elastic forces of the springs, as well as containing pairs of passive and active elements, the latter of which are connected with the mentioned levers interacting with each other and obstructive rotation the wheels when the brakes are on.

This method was developed for wheelchairs used for transportation of disabled people by accompanying persons, and cannot be implemented on wheelchairs designed for independent movement of disabled people using the muscular strength of the hands.

A device for the safe movement of a wheelchair (RU 2509545 C2, IPC A61G 5/10, published on 03/20/2014), including a one-way bearing mounted in the parking drum so that the wheelchair tires can move forward and cannot move backward, thereby preventing wheelchair rolling backward or sliding forward.

The disadvantage of this device when moving uphill is the need to press the parking drum containing a single-acting bearing to the tire wheel of a wheelchair with a force that provides a friction force greater than the rolling force directed parallel to the downward slope plane. Pressing the parking drum against the wheel tire with the required force inevitably causes its deformation and requires additional energy loss to move the deformed zone along the tire perimeter during movement, as well as to create additional force for the disabled person in addition to that necessary to ensure upward movement.

The disadvantage of the device should also include the fact that when driving on a wet surface, wet tires leads to a decrease in the coefficient of adhesion between the tire and the parking drum and reduce the efficiency of the device.

The closest analogue to the claimed invention in terms of the totality of design features is the braking device for lifting safety of a wheeled vehicle (RU 2570504 C1, IPC A61G 5/10, published on 12/10/2015). The device includes a bearing arm pivotally mounted on the vehicle frame by means of a plate with an adjusting device with a movable friction element at its end, as well as a brake lever with the function of a control element connected to the carrier arm. The brake and carrier levers are structurally integrated with each other and with the friction element, the hinges of the installation of the brake lever and the friction element are also combined with each other, with the formation, in the aggregate, of a two-arm locking pawl lever. The pawl lever is fixed on the mounting plate by means of a hinge, with the possibility of fixing at least one stop-limiter and a spring in three positions - non-working, working not turned on and working turned on, that is, on duty. In this case, the role of the ratchet wheel is performed by the tire of the wheel, and the ratchet is performed by the locking lever-dog. Braking / locking is carried out automatically due to the “jamming” of the pawl lever between the axle and the tire.

The presence in the device of the control lever, which has three fixed positions for each mode of movement, provides the convenience of choosing and switching on the one necessary for the existing conditions. Due to the presence of a pawl lever pressed against the tire by a spring, the energy consumption during movement in the "on" mode practically does not increase.

The disadvantages of the device include a partial rotation of the wheel back due to deformation of the tire when the stop of the pawl lever is pressed into it, as well as a decrease in the effectiveness of the device when the wheelchair is moving in atmospheric precipitation (rain, snow), on wet and especially dusty or contaminated surfaces, etc. factors that reduce the coefficient of adhesion between the tire and the pawl.

By the combination of essential features, the specified braking device for the safety of lifting a wheeled vehicle is accepted as a prototype.

The aim of the invention is to obtain the possibility of preventing the wheelchair from starting to move and rolling back when moving hands on the wheel hoop in the process of climbing through the use of an automatic device that prevents the wheel from rotating in the direction corresponding to backward movement, which will ensure the safety of independent movement of wheelchair users by eliminating the possibility spontaneous uncontrolled rolling of wheelchairs backwards with a high probability of their falling.

The technical result of the invention is to improve the technical and operational characteristics of a wheelchair by increasing its safety and facilitating its control during lifting.

The objective of the invention is to create a device that ensures the movement of a disabled person in a wheelchair up a ramp or other inclined surface, excluding movement back at the moment of transferring hands on the wheel hoop or releasing the wheel hoop, which does not create additional force due to the presence of the device and its operation, protected from decrease in efficiency when exposed to atmospheric precipitation, as well as movement on wet and, especially dusty or contaminated surfaces.

The problem is solved in the following way.

A device that ensures the safety of a wheelchair when lifting, having a pair of automatic recoil brakes symmetrically installed in both running wheels, including two additionally installed overrunning clutches that can be turned off, mounted in the bushings of the main wheels, each of which includes a fixed sprocket connected (fixed) by a lever with the stroller frame, a separator with rollers located in its grooves, which can be rotated around its axis and connected to the lever, which acts as a control device and is held in the extreme position by a return spring, thereby ensuring the location of the rollers in the zone of direct interaction of their cylindrical surfaces in contact with the working surfaces of the sprocket and clutch, allowing (providing) the possibility of rotation of the main wheels of the wheelchair only in the direction of movement forward (uphill), the control lever connected by a rod to the control lever parking brake, which is at the same time a device for controlling the overrunning clutch, which allows, by stretching the return spring, to turn the separator and transfer the clutch to the off non-working state, in which the rollers are located in the recesses of the sprockets and do not interact with the working surface of the clutch, allowing (providing) the possibility of rotation of the main wheels of the wheelchair in any direction.

The proposed device is illustrated by figures 1, 2, 3 and 4.

In FIG. 1 shows a general view of the device from the front with a cut along the axis of the wheel, where 1 is an asterisk; 2 - bushing (hub); 3 - separator; 4 - rollers; 5 - wheel axle; 6 - wheel spokes; 7 - clutch control lever; 8 - bearings; 9 - lever for fixing the sprocket; 9 - wheel fork or frame; 10 - frame (fork).

In FIG. 2 shows a general view of the device from the side with a cut along the end of the overrunning clutch rollers in the off position.

In FIG. 3 shows a general view of the device from the side with a cut along the end of the overrunning clutch rollers in the on position (uphill movement).

In FIG. 4 shows a diagram of mounting the device on a wheelchair and a device for controlling operating modes, where 11 is a cable (traction); 12 - return spring.

The operation of the device is as follows. The device is controlled by a modes control lever, similar to the prototype, and has three fixed positions "off", "on", "parking brake", with the exception that each control lever is additionally connected by means of a cable drive (cable) or traction with lever 7 ( Fig. 1 and Fig. 4) rotation of the separator 3 (Fig. 2 and Fig. 3). The asterisk 1 is fixed by means of the locking lever 9 connected to the frame or fork 10 (Fig. 1)

When the control lever is in the "off" position, the cable 11 moves the clutch control lever 7 to the extreme position in the forward direction, stretching the return spring 12 (Fig. 4). At the same time, the separator 3 rotates around its axis on bearings 8 and moves the rollers 4 relative to the sprocket to the extreme position, while lowering them into the recesses of the sprocket (Fig. 2). In this position, a gap is formed between the bushing and the rollers and the wheel is free to rotate in any direction. The force required to stretch the spring does not exceed 5 N.

To enable the device in operation, the control levers must be moved to the fixed "on" position. At the same time, the control cable 11 releases the return spring 12 (Fig. 4), and it turns the clutch control lever 7 at an angle of about 20° to the extreme position in the direction of backward movement (Fig. 4). In this case, the separator 3 moves the rollers 4 to the position of their simultaneous interaction forming with the sprocket 1 and the bushing 2. The return spring, remaining in a partially stretched state, provides automatic gap compensation in the bushing-roller, roller-sprocket mates, which practically eliminates the possibility of reverse rotation, both the hubs and the wheels of the wheelchair in the rearward direction. When the wheel rotates forward, the rollers, overcoming the rolling resistance force (the value of which is negligible), move into the zones of the sprocket deepening, ensuring free rotation of the wheel in the direction of movement forward.

When the control lever is in the "parking brake" position, the cable 11 for moving the clutch control lever 7 is loosened, while the clutch remains in the on state.

Bibliographic list

1. Pat. 2459605 Russian Federation, MPK6 A61G5/06. Automatic vehicle brake, mainly for moving a person up stairs / Krasilnikov A.A., Samoilov A.D., Semenov A.G., Elizov A.D.; applicant and patent holder St. Petersburg. state polytechnics, un-t. - No. 2011106450/12; dec. 02/21/2011; publ. 27.08.2012., Bull.

2. Pat. 2509545 Russian Federation, MPK6 A61G 5/10. Device for the safe movement of a wheelchair / Lo V.K., Wong V.M.; applicant and patentee Lo V.K. (PRC). - No. 2011109867/12; dec. 03/16/2011; conven. priority 03/17/2010 CN 201020136764; publ. 03/20/2014, Bull. No. 8.-13 p.

3. Pat. 2570504 Russian Federation, MPK6 A61G 5/10. Brake safety device for lifting a wheeled vehicle / Krasilnikov A.A., Samoilov A.D., Semenov A.G., Elizov A.D.; applicant and patent holder “Scientific. -production association "Affordable Mobility". -No. 2014131514/12; dec. 07/29/2014; publ. 10.12.2015, Bull. No. 34. - 16 s.

Claims (3)

1. A device that ensures the safety of a wheelchair during lifting, containing a pair of automatic recoil brakes symmetrically installed on both running wheels, characterized in that two overrunning clutches are additionally installed, with the ability to turn them off, mounted in the bushings of the main wheels, each of which includes a fixed sprocket, fixed by a lever with the frame of the stroller, a separator with rollers located in its grooves, which can be rotated around its axis and connected to the lever that performs the function of a control device and is held in the extreme position by a return spring, thereby ensuring the location of the rollers in the area of direct interaction of their cylindrical surfaces in contact with the working surfaces of the sprocket and clutch, which ensures the possibility of rotation of the main wheels of the wheelchair only in the direction of movement forward, the control lever connected by a rod to the parking brake control lever ohm, which is at the same time a control device for the overrunning clutch, which allows, by stretching the return spring, to turn the separator and transfer the clutch to the off non-working state, in which the rollers are located in the recesses of the sprockets and do not interact with the working surface of the clutch, providing the ability to rotate the main wheels of the wheelchair in any direction . 2. A device that ensures the safety of a wheelchair during lifting, according to claim 1, characterized in that the overrunning clutches are made inside the bushings of the main wheels and are protected from external factors - rain, snow, dirt. 3. A device that ensures the safety of a wheelchair during lifting, according to claim 1, characterized in that the performance of overrunning clutches does not depend on the degree of wear of the tire tread and does not require adjustments.

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