CZ308659B6 - Wheel for moving up the stairs - Google Patents

Abstract

The wheel for moving up the stairs is composed of a central carrier (1) with two or more arms, at the ends of which there are movable segments (2) forming a complete wheel circle.

Description

Wheel for moving up the stairs

Field of technology

The invention relates to the wheel shape of a mobile device which allows you to ride on stairs.

Prior art

Five categories of technical means are currently used to move (ride) up the stairs.

The first category includes crawler bogies, possibly supplemented by auxiliary ramps or mechanisms for lifting a step, as well as combined wheel and crawler bogies with auxiliary belts for moving up stairs and wheel bogies with auxiliary mechanisms for lifting a wheel to a step. The principle of movement here is the rolling of the belt, or wheels, on the surface of stairs with the cooperation of auxiliary lifting belts or mechanisms. The disadvantage of crawler chassis is higher energy consumption and problems with wedging small objects between the belt and wheels.

An example of a solution is in WO 2004/108045, "POWERED WHEELED VEHICLE CAPABLE OF TRAVELING ON LEVEL GROUND, OVER UNEVEN SURFACES AND ON STAIRS" and WO 1988/003012 - "WHEEL-CHAIR FOR THE HANDICAPPED, IN PARTICULAR FOR NEGOTIATING STAIRS".

The second category includes multi-arm wheels with two, three (Weinstein's wheel) and four arms equipped with smaller driven wheels at the end, where when moving on a plane the wheel does not turn with the arms and smaller wheels are used to ride on a flat surface and when moving on stairs begins turn the wheel with the arms that lift the wheel like levers and the smaller driven wheels are braked, or pushes the wheel forward. The disadvantage is the uneven rocking motion when moving up the stairs and the higher construction complexity of the wheels.

Examples solving a similar problem are in WO 2000/054720 - "SYSTEM AND METHOD FOR STAIR CLIMBING IN A CLUSTER-WHEEL VEHICLE" and WO 2008/002050 "DRIVING SYSTEM".

The third category consists of walking systems, where the means for moving up the stairs are different shapes of mechanical legs. These walking chassis are often combined with classic wheels, the result is hybrid chassis, or. the individual mechanical legs are provided at the ends of the wheel, the result is again a hybrid chassis. The disadvantage is the structural complexity.

The fourth category consists of polymorphic wheels, where the wheel changes profile from a circular shape when moving along a plane to a profile corresponding to the shape of the step. The change of the profile is caused by various internal mechanisms, usually it is a radial extension of individual wheel segments, the source is moved, for example, by a driven eccentric cam inside the wheel. The disadvantage is the structural complexity.

An example of a solution is in CN 101066235 - "Electrically driven stairs climbing a hard cart and its deformation wheel".

The fifth category consists of special profiles of fixed wheels, where the wheel is provided with a different number of protrusions with different shapes of the contact surface and rolling of the shape of individual wheel protrusions on the surface of the stairs moves the wheel up the stairs. A major drawback of the wheels patented so far is the too jerky movement when moving on a plane. So far, the following shapes of the contact surfaces of the wheel segments have been patented: cycloid, three protrusions according to DE 3321742 - "Drive unit for a lifting device which can travel over stairs involuta", three protrusions according to - US 4674757

-1 CZ 308659 B6 „Stair-climbing wheel utilizing an involute curve configuration“; logarithmic (Archimedes) spiral, three protrusions according to CN 101462563 - "Archimedes spiral wheel for stair climbing vehicle and double-rocking lever mechanism". This solution, as the only one of the fifth category of wheels for stairs, simultaneously solves driving on a plane by means of sliding circular segments, which cover the fixed projections, the other mentioned solutions use other sliding wheels for driving on a plane.

In the case of the security document CN 101462563, the fixed projections are covered by the auxiliary mechanism when the plane segments are extended when moved along the plane. However, the circular segments do not form a complete circle and there is a jerky movement when driving on the plane, which is a significant disadvantage of this solution. When moving up the stairs, the circular segments are folded under the fixed protrusions and the wheel rolls on logarithmic spiral surfaces from one side of the fixed protrusions. This is another significant disadvantage of this arrangement, since the rolling surfaces in the shape of a logarithmic spiral are only on one side of the fixed projections and the wheel and with it the mobile bogie only has to go up and down the stairs, which is especially unsuitable for passenger transport. The functional element when driving on a plane is the extended circular segments and the functional element when driving on stairs are the fixed protrusions of the carrier with a one-sided surface in the shape of a logarithmic spiral.

The essence of the invention

The above-mentioned disadvantages are largely eliminated by the technical device, which is a stair wheel composed of two or more rotating circular segments, which form a complete circular wheel profile for movement on a flat surface around a common carrier with the arms. Circular segments are a functional element when moving on a plane and moving up stairs. To move the wheel up the stairs, the individual segments are rotated by a suitable angle into position so that the circular segment rests tangentially on the tread of the step. The dimensions of the individual segments, the center of rotation of the individual segments and the angle of their rotation are chosen so that the length of the arc along which the circular segment rolls is equal to the length of the tread of the average step and at the same time the circular segment abuts tangentially on the tread when rotating the wheel around the top of the previous segment. . The angle of rotation of the rotating segments can be used to adapt the wheel to the height of the stairs. The advantage of using circular segments as function surfaces when moving up stairs is the possibility of tilting them in both directions. Therefore, a vehicle equipped with these wheels does not have to reverse when driving down stairs.

Since the turning radius (distance of the contact point to the center of the carrier) changes when rolling around the circumference of the circular segment, it is possible to control the rotational speed of the carrier by means of a suitable control and sensor system so that the speed of movement is constant. This position control is performed by means of sensors sensing the shape of the step (optical, ultrasonic) and a control system of the mobile means, which positively controls the individual wheels on the basis of their position relative to the step. This solution is suitable for moving up and down stairs. The wheel must always be in the specified position relative to the step.

Explanation of drawings

The stair wheel is illustrated in more detail in the accompanying drawings, in which Fig. 1 shows the wheel in a position for moving on a plane, Fig. 2 shows the wheel in a position for moving on stairs.

Examples of embodiments of the invention

The stair wheel according to the invention is assembled as a wheel with three ring segments 2 connected to the arms of a segment wheel carrier L. The three ring segments 2 are driven by three linear drives. When moving along the plane, the wheel retains a circular shape, at

- 2 EN 308659 B6 approaching the stairs, the individual segments 2 are rotated to the position for driving up the stairs by means of linear drives. After approaching a flat surface, or in the mezzanine, the wheels are again aligned in a circular shape suitable for movement on a plane. In place of linear drives, moving screws are used, the nut of which is driven by electric motors.

Industrial applicability

The bicycle for riding up the stairs according to the invention can be used in all mobile devices, where it is necessary to move up and down the stairs - wheelchairs, beds for transporting patients, stair climbers, transporting people and goods on the stairs, mobile robots, etc.

Claims (3)

PATENT CLAIMS A wheel for moving stairs, characterized in that it is composed of a central carrier (1) 5 with two or more arms, at the ends of which movable segments (2) forming a complete wheel circle are arranged. Stair wheel according to claim 1, characterized in that the outer shape of the segments (2) corresponds to a circular section, the size of which is determined by the number of arms on the central carrier (1) and the size of a conventional step. Stair wheel according to the preceding claims, characterized in that it has the shape of an ideal circle when moving along a plane, while the individual segments (2) are tilted from the central carrier (1) when moving up the stairs so as to form protrusions for tangential abutment of the segments (2) on the 15 step surface of the step.