DE102005008879A1 - Rolling walking aid for overcoming handicap has wheels arranged on pivotable front structure to be one behind the other in direction of travel and offset with respect to each other in vertical direction - Google Patents

Abstract

The device (1) has a chassis (5) and a forward structure (10) that is pivotably joined at an upper region to the chassis via a pivot axle (DG3) and at least one front wheel (2) in the lower region of the front structure and at least one higher wheel (7), whereby the wheels are arranged one behind the other in the direction of travel and offset with respect to each other in the vertical direction.

Description

The The invention relates to a rollator, wheelchair or the like with a frame and a stem, the stem on an upper Area over a pivot axis is hinged to the frame pivotally.

at the handling of rollators by handicapped people or when using wheelchairs it comes to difficulties if the ground is not flat or an edge such as a sidewalk edge is present, the overcoming a height difference requires. Here are already at relatively low obstacles either high horizontal forces (Pushing forces) necessary or it is even impossible to overcome the obstacle because the devices tip the front wheels blocked by the obstacle forward. Mostly the operator of the rollator must overcome the obstacle Raise or at least tilt the rollator.

The publication DE 10153214 A1 discloses a walker with a hinged front frame. In this walker is provided that the front frame in blockade of the front wheels by an obstacle (eg curbside) pivots against a pivot point against the direction of the rear frame and thereby one or more spring elements upsets the front frame after overcoming the blockade in Press back direction.

The underlying object of the present invention is a Device for overcoming a To propose obstacles that are particularly user-friendly and is safe.

The The object is achieved by a rollable walker according to claim 1. optional or advantageous embodiments or modifications arise entirely or partly from the dependent ones claims and / or the following description.

at This rollable walker can be a walker, a Wheelchair, walker or similar device, which support the locomotion of the handicapped by means of a frame, which on wheels or wheels is movable.

at the frame may be a tubular frame, in particular round or square tube trade. The frame is preferably collapsible trained and can depending on the design various additional Components such as a seat, a shopping basket or a storage device exhibit.

Of the Stem is above on this frame articulated a substantially horizontal pivot axis. The stem can in special embodiments also be designed removable or hinged. In the lower area, especially at the lower free end of the stem, are at least a front wheel and at least one height wheel provided, wherein the Depth knob in the direction of travel in front of the front wheel and in the vertical direction above the Front wheel is arranged. The direction of travel is understood to mean the straight-ahead direction of travel.

By the special construction of the swiveling stem is ensured that the rollable walker when overcoming an obstacle does not tend to overturn in the direction of travel, because the stem safely in the pivoted state by the altitude wheels supported becomes.

Especially can Depth knob and front wheel in Höhenradachsenrichtung and / or Vorderradachserichtung also offset from each other and / or overlapping be arranged.

In preferred embodiments, the stem comprises one or more front legs, at the free end (s) of which the wheels are arranged. This embodiment thus also comprises a rollator or wheelchair, with one or more front legs, which are each pivotally hinged to an upper portion and in a lower region have two wheels arranged one behind the other in the direction of travel, which are horizontally offset from one another. In the case of only one front leg, for example, it can be articulated symmetrically, in particular encompassing from the outside, on side cheeks of the rollable walking aid or centrally in the center region of the frame. Such embodiments could, for example, Sportroll find use in chairs where often a stem with a single front wheel is provided. An embodiment with two front legs is used particularly advantageously in rollators. Preferably, the pivoting movements of the individual front legs are decoupled from each other, but they can also be rigidly coupled together.

Preferably is the pivot axis with respect to the front wheel axle, so the axis around the front or the front wheels when driving straight ahead, turn to the rear in direction of travel and arranged offset upwards and in particular such, that the front wheel axle precedes the pivot axis. Especially advantageous is an offset angle gamma of about 10 ° to 20 ° from the connecting line pivot axis-front wheel axle across from the vertical in a vertical plane, which is arranged parallel to the straight-ahead direction is.

at preferred embodiments is the elevation wheel axis with respect to the front wheel axle in the direction of travel to the front and arranged offset upwards and in particular such that the elevation wheel axis the front wheel axle runs ahead. Through the connecting line of Höhenradachse-front wheel axle and the Horizontal is an angle beta in a vertical plane that is arranged parallel to the straight-ahead direction, clamped, which is preferably in the range between 15 ° and 35 °.

On level surface and in non-swung-in condition of the stem the front wheels are not however, the altitude wheels on on the ground. In particular, the front wheel axle and the Höhenradachse a height difference in the vertical direction of more than 5 cm, more than 7 cm or more than 10 cm up.

The front wheels and the altitude bikes can be identical be educated. In preferred embodiments, however, the Diameter of front wheel and height wheel different sizes, In particular, the front wheel is larger in diameter, e.g. 1.5, two or three times formed larger as the high wheel.

front and / or altitude wheel can smaller in diameter than a rear wheel of the rollable walker be educated. For example, the front wheels may be in diameter smaller than 10 cm, smaller than 7 cm or smaller than 5 cm be, or the diameter of the front wheels is up to the 0.75, 0.5 or 0.25 times the diameter of the rear wheels.

While at earlier, in particular rigid rollable walkers, the height of which can be overcome by pushing Obstacles over the diameter of the front wheels was limited, is in the inventive rollable walker this maximum height essentially about the height difference the Höhenradachse and the front wheel axle limited. Thus, you can Compared to the prior art smaller diameter for the front wheels and / or the altitude wheels used but at the same time reach the same surmountable maximum height become.

at Developments of the invention can Depth knob and front wheel have different widths, in particular the altitude wheel be formed wider than the front wheel and thus in overcoming a Obstructing the lateral stabilization.

After this the altitude wheel only in overcoming is used by obstacles, is the claim in terms the smoothness and the rolling resistance to the Höhenrad lower. The altitude wheel can for example as a roller, in particular as a roller with a strong profile, be formed, in particular as a roller with a width greater than the diameter of the roller. Further, the tire of the altitude wheel from another, in particular a softer material than the Tires of the front wheel exist.

at preferred embodiments is a supporting device, on which the user during the Go support can, provided. The support device is usually designed as a handle bars, but can also as Aufstützvorrichtung for the Forearms or armpits may be formed. The pivot axis is preferably at about halfway up the support device arranged.

to Limitation of the pivoting movement of the stem can be a first and second Stop be provided, wherein the first stop the pivoting movement limited in the direction of travel and the second stop the pivoting movement limited to the direction of travel. Preferably, the stops are displaceable, so that the operator - if he wants to use a different swivel range - the stops are simple, in particular implement without the use of tools, in particular can change.

at an advantageous embodiment, the rollable walker a or more return spring elements on, which are arranged between the stem and frame and the Counteract pivoting of the stem. Preferably, too one or more damper elements, in particular viscous damper elements parallel to the return spring elements be switched so that the pivoting and swinging of the Substructure muffled is. The damper elements can act translational or rotational.

Especially in particularly simple embodiments can also apply to the reset elements be omitted, especially if the above-defined angle beta smaller than the above-defined angle gamma is formed.

at Further developments of the rollable walker can also be provided that the front wheel to facilitate cornering over a Swivel joint is hinged to the stem, the swivel an upright standing pivot axis, and the pivot eccentric with connected to the front wheel.

Farther can shock absorber elements be provided, which a deflection of front wheel and / or Depth knob in a vertical or substantially vertical direction.

Further Features, Details, Benefits, Combinations and Effects the basis of the invention are from the following embodiment refer to. Show it:

1 a schematic side view of a known from the prior art rollator or wheelchair;

2 . 3 a schematic side view of an embodiment of a rollator based on the invention;

4 - 9 a sequence of schematic side views of the rollator 2 while overcoming an obstacle;

10 a schematic diagram of a possible embodiment of the stem of the rollator from the 2 to 9 ,

The 1 shows a conventional rollator or wheelchair in a schematic side view, wherein the straight-ahead direction of the rollator in the representation extends from right to left as indicated by the arrow F.

The rollator 1* consists essentially of a frame 5 * , on each of which at the lower end on each side two wheels via hinges DG1 * and DG2 * are attached, with which the devices can roll on the floor. In the side view in 1 are a front wheel 2 * and a rear wheel 3 * to see. In the upper, rear area of the frame 5 * are handle bars 4 * intended.

When using the rollator 1* is the operator in the direction of travel F behind the rollator, takes this on the handle bars 4 * and pushes the rollator 1* in direction of travel F.

The rollator 1* is in 1 on a level surface and is against an obstacle 6 * pushed, which is representative of a curb or similar barrier with difference in height.

With the conventional rollator 1* Even with relatively low obstacles either high horizontal forces (pushing forces) are necessary or it is even impossible to overcome the obstacle, because the devices tilt forward around the front wheels blocked by the obstacle.

To illustrate this problem are in 1 schematically shows the geometric conditions and the effective forces in rollators and wheelchairs:
About the handlebars 4 * Both the vertical support force of the pushing person, as well as the horizontal pushing force H are initiated. About the wheels 2 * and 3 * the support forces are introduced into the ground.

In the 1 shown vertical force G represents the resultant of all vertical forces. In addition to the support force of the pushing person also occur the weight of the devices and in addition to wheelchairs nor the weight of the person to be transported as vertical forces.

On a level surface, the horizontal pushing force H is small and due to the fact that the resulting vertical force between front 2 * and rear wheel 3 * attacks, stable handling is possible.

In order to calculate the required horizontal pushing force H for overcoming an obstacle or the condition according to which the devices tilt forward are in 1 represented the force vectors in a state in which the front wheel has just lifted from the ground and is supported on an edge with height difference e to the ground. In this state, the balance of power is to be set up below.

The front wheel is with respect to its pivot DG1 * torque-free and here applies:

The condition for the non-tilting of the device around the swivel DG1 * forward by excessive horizontal force H (G _h = 0) is:

Finally surrendered the following geometric relationships:

Summarized Equation 1 gives:

With equation 3 follows:

Equation 5 in Equation 2 provides:

Equation 7 represents a condition for the radius r which is at least required to overcome a given height difference e under the existing geometrical conditions. Squaring and multiplying leads to the quadratic equation:

The quadratic equation 8 has the two solutions:

Physically only the larger one makes sense both solutions.

in the Following are two examples of the surmountable height differences determined with existing rollators:

Assumption 1: Person supports on the rollator (normal case)

• approximate Dimensions: s = 80 cm; c = 40 cm; d = 20 cm; r = 7 cm

Hence the relationship between r and e: r ≈ 2.25 × e

you can therefore a maximum of one height difference of e ≈ 3.1 cm overcome.

Assumption 2: Person supports not on the rollator, it only affects the weight of the rollator in vertical direction (extreme case)

• approximate Dimensions: s = 80 cm; c = 30 cm; d = 30 cm; r = 7 cm

Hence the relationship between r and e: r ≈ 5 × e

you can therefore a maximum of one height difference of e ≈ 1.4 cm overcome.

in the unfavorable Case is the surmountable Height difference with existing rollators at only 1.4 cm.

The 2 and 3 show a schematic side view of an embodiment of a rollator, wheelchair, walker or the like - hereinafter called rollator - based on the invention.

The rollator 1 includes - similar to the rollator 1* to 1 - a frame 5 , on the upper, rear area handle bars 4 are arranged. The handle bars 4 can be designed adjustable in height. In the floor area of the frame are in the rear area rear wheels 3 arranged via a swivel DG4.

The essential difference to the walker 1* to 1 lies in that instead of the front wheels 2 * in the front area of the frame 5 swiveling legs on both sides 10 are provided, each having its upper end at a height that is approximately the center of the frame 5 corresponds, via one or more hinges DG3 with horizontal pivot axis on the frame 5 are articulated. These swivel legs 10 each have a front wheel at its lower end 2 and a high wheel 7 on, which are attached via a hinge DG1 or DG2 with horizontal axis of rotation on the leg. Optionally, one or more restoring elements, in particular return springs, can be provided, which are provided between the frame 5 and thighs 10 are arranged, such that a pivoting of the leg 10 to the frame 5 counteracted.

Although in 2 already an obstacle 6 is shown, on which the rollator 1 with his front wheel 2 in driving direction F, is in the 2 each of the rollator 1 with swung thighs 10 shown. This can be seen from the fact that the free end of the leg extending above the pivot DG3 10 at a stop 8th is applied, which blocks a pivoting of the lower leg portion in the direction of travel F. The rollator 1 is thus shown in a deployed operating state (normal position), which he also on a level surface 11 without hindrance 6 would take.

In this normal position is the thigh 10 in the forward direction, so that the connecting line pivot DG3 and pivot DG1 is inclined in the illustrated side view relative to a vertical by an angle gamma, wherein the corner of the angle is located in the pivot DG1. The altitude wheel 7 stands in the direction of travel F respectively diagonally above the front wheel 2 of the same thigh 10 , so that over the horizontal, swivel DG1 as vertex and swivel DG2 spanned an angle beta.

The following is for the mechanism 2 and 3 demonstrating its effectiveness through an exemplary consideration of the balance of power and further details and features open beard.

G:

Summe der vertikalen Kräfte (Gewichtskräfte und Stützkräfte)

G_v:

Anteil der vertikalen Kräfte, die sich am Vorderrad bzw. Höhenrad abstützen

G_h:

Anteil der vertikalen Kräfte, die sich am Hinterrad abstützen

H:

horizontale Schiebekraft

c, d, s, L:

Hebelarme am Gerät

e:

zu überwindender Höhenunterschied

beta, gamma:

Neigungswinkel am Gerät

The following abbreviations are used:

G:

Sum of vertical forces (weight forces and support forces)

G _v:

Proportion of vertical forces that are supported on the front wheel or the height wheel

G _h:

Proportion of vertical forces supported on the rear wheel

H:

horizontal pushing force

c, d, s, L:

Lever arms on the device

e:

to overcome height difference

beta, gamma:

Tilt angle on the device

In 3 is the rollator 1 shown in a position in which he at particular maximum possible height difference against an edge 6 encounters. The rear front wheel has just lost contact with the ground. The vertical weight force G _v is fully supported by the height wheel 7 from. The front wheel 2 acts as an abutment for the horizontal force H. In 3 All wheels have the same diameter. As a result, the height difference e is equal to the vertical distance between pivot DG1 and DG2.

The moment equilibrium for the leg around DG3 provides the relationship:

Switching from Equation 10 yields:

The moment balance for the frame around the swivel of the rear wheel (DG4) provides the relationship:

Equation 11 is inserted into Equation 12 and resolved to H / G:

The condition for the non-tilting of the device about the swivel DG3 forward by excessive horizontal force H (G _h = 0) is:

equation 13 delivers for given geometric relationships a relationship between expended horizontal forces and existing vertical forces.

This relationship can be structurally designed so that ergonomically advantageous Conditions for the pushing person to be realized. As a secondary condition is Note equation 14 (limit H / G ratio).

in the The following is shown by means of two examples that with the proposed Mechanism overcome larger height differences can be.

1. For rollators it is assumed:

• approximate Dimensions: s = 80 cm; c = 40 cm; d = 20 cm; L = 40 cm; e = 7 cm; β = 30 °; γ = 15 °

For this results a H / G ratio according to formula 13 of 0.45 at a limit H / G ratio according to formula 14 of 0.72. Such a device would be with it able to make a difference in height of 7 cm (measured, maximum height from lowered curbs on road junctions) easily overcome.

2. For wheelchairs will accepted:

• approximate Dimensions: s = 80 cm; c = 40 cm; d = 30 cm; L = 50 cm; e = 7 cm; β = 20 °; γ = 15 °

Here is the H / G ratio at 0.56. The limit H / G ratio is 0.85. Thus, the mechanism can also be used for wheelchairs.

The Force action of a return spring to be used is in the previous Calculations neglected Service. However, this affects the position for which the Balance of power was not yet set up. In the positions where the spring strikes, are the leverage ratios cheaper which has a positive effect on the H / G ratio. A closer one Interpretation under consideration all driving conditions is computerized Perform simulation tools (FE or MKS method).

In the 4 to 9 is the working principle of the rollator 1 to 2 and 3 when crossing over an edge 6 shown with height difference e.

4 shows the rollator 1 on level ground in normal position during rollator 1 on the edge 6 zufährt. The direction of travel F runs in the illustration from right to left. In 5 pushes the front wheel 2 straight on the edge 6 at.

Will from this position in 5 off at the handle bars 4 further pressed in the direction of travel F, the leg works 10 after overcoming the support torque in the stop around the swivel joint DG3 to the rear around until the height wheel 7 on the ground raised by the height difference e ( 6 ).

Further pushing in direction F lifts the front wheel over the edge, as in 7 is shown. In this position are both Höhenrad 7 as well as front wheel 2 on the ground. A second stop 9 who is on the rack 5 is arranged below the pivot DG3 prevents over-rotation of the mechanism. In particular, the second stop limited 9 the pivoting movement of the leg 10 against the direction F.

If the angle β is greater than the angle γ (as in 7 the case), the device remains in the in 7 stand position shown. For folding back to the normal position after 8th , can be a suitable spring (return spring) between frame 5 and thighs 10 provided at the latest when the angle γ passes through the zero position, with a counter force on the relative rotation between the frame 5 and thighs 10 responding. Preferably, compression, tension or torsion springs are used. Possibly also viscous damping elements should be provided so as not to make the folding back to jerky. These damper elements can act translationally or rotationally.

Is β smaller as γ, will the mechanism is pushed back to normal position by gravity and there will be no extra Return spring needed. this could a particularly cost-effective Execution of the Represent rollators.

Lifting the rear wheel over the edge 6 ( 9 ) is easily possible due to the given geometric conditions.

10 shows a schematic representation in side view of an exemplary embodiment of the connection of the front wheel 2 via a vertical swivel joint on the leg 10 of the rollator 1 according to the 2 to 9 to support cornering.

In the upper area of the 10 the hinge DG3 is shown again, from where the leg 10 extends obliquely downward in the direction of travel. In straight extension of the thigh 10 down that is Depth knob 7 via the swivel DG2 on the leg 10 attached. In the lower half, preferably in the lower third, of the thigh 10 is a vertical swivel in the thigh 10 mounted, which has a vertical axis of rotation (vertical axis) OP to the front wheel 2 can be turned. The front wheel 2 is eccentrically connected to the vertical pivot, leaving another vertical through the swivel DG1 of the front wheel 2 and the rotation axis OP have a distance t, preferably the simple radius of the front wheel 2 is.

Thus, a device is presented which may have all or part of the following advantages:
An operator no longer has to interrupt his forward movement to overcome an obstacle, but can, as it were, push away over the obstacle. Thus, especially in rollators based on the invention, people with walking difficulties can easily overcome the height differences that occur in everyday life. The wheel diameter no longer plays a role and can be designed much smaller than in known rollators. Furthermore, the wheels may have different diameters. For wheelchairs the same considerations apply. Here, however, it should be noted in addition that the resulting vertical force is usually large and thus large horizontal sliding forces are required.

Claims (12)

Rollator ( 1 ), Wheelchair or the like - hereinafter called rollable walker -, with a frame ( 5 ) and with a stem ( 10 ), which at an upper area on the frame ( 5 ) is articulated pivotably about a pivot axis (DG3), characterized in that in a lower region of the stem ( 10 ) at least one front wheel ( 2 ) and at least one altitude wheel ( 7 ) are provided, which are arranged one behind the other in the direction of travel and vertically offset from each other. Rollable walker according to claim 1, characterized in that the stem one or more front legs ( 10 ) whose pivotal movements are decoupled from one another or, in particular, are rigidly coupled to one another, wherein preferably at each front leg ( 10 ) one front wheel each ( 2 ) and a height wheel ( 7 ) are arranged. Rollable walker according to claim 1 or 2, characterized characterized in that the pivot axis (DG3) in the direction of travel behind the front wheel axle (DG1) is arranged and / or in side view the connecting line between the swivel axis (DG3) and the front wheel axle (DG1) with respect to the direction of travel backwards relative to the vertical by one Angle gamma is inclined, preferably in a range between 10 ° and 20 °. Rollable walker according to one of the preceding claims, characterized characterized in that the front wheel axle (DG1) in the direction of travel behind the Höhenradachse (DG2) is arranged and / or in side view the connecting line between front wheel axle (DG1) and vertical wheel axle (DG2) and the horizontal form an angle beta, which is open in the direction of travel and which is preferably in a range between 15 ° and 35 °, in particular between 25 ° and 35 ° for rollators and between 15 ° and 25 ° for wheelchairs. Rollable walker according to one of the preceding claims, characterized in that the height difference between Höhenradachse (DG2) and front wheel axle (DG1) and / or between the lower edge of the Höhenrads ( 7 ) and lower edge of the front wheel ( 2 ) is more than 5 cm, preferably more than 7 cm, in particular more than 10 cm. Rollable walker according to one of the preceding claims, characterized in that front wheel ( 2 ) and altitude wheel ( 7 ) have a different diameter, in particular, that the front wheel ( 2 ) has a larger diameter than the height wheel ( 7 ). Rollable walker according to one of the preceding claims, characterized in that the front wheel ( 2 ) and / or the altitude wheel ( 7 ) a smaller diameter than a rear wheel ( 3 ) of the rollable walking aid, preferably a diameter smaller than 75%, in particular smaller than 50%, than the diameter of the rear wheel ( 3 ). Rollable walker according to one of the preceding claims, characterized in that the rollable walker a support device on which a user during walking can support, in particular handle bars ( 4 ), wherein the pivot axis (DG3) is arranged approximately at half the height of the support device. Rollable walker according to one of the preceding claims, characterized in that a first ( 8th ) and / or a second stop ( 9 ) is provided which limits the pivoting movement of the stem in the direction of travel or against the direction of travel, wherein it is preferably provided that the first stop ( 8th ) above the pivot axis (DG3) and / or the second stop ( 9 ) are arranged below the pivot axis (DG3). Rollable walker according to one of the preceding claims, characterized in that between stem ( 10 ) and frame ( 5 ) one or more return spring elements are provided, which the pivoting of the stem ( 10 ) counteract and are preferably designed as compression-tension or torsion springs. Rollable walker according to one of the preceding claims, characterized in that between stem ( 10 ) and frame ( 5 ) one or more damper elements are provided which control the pivotal movement of the stem ( 10 ) and are preferably designed as translational or rotary dampers. Rollable walker according to one of the preceding claims, characterized in that the front wheel ( 2 ) over one opposite the front wheel ( 2 ) eccentrically arranged rotary joint with a substantially vertical axis of rotation (OP) to the stem ( 10 ) is articulated.