DE20310604U1 - Steering arrangement for perambulator, pushchair or suchlike has at least two interconnected and vertically rotationally movable axle carriers mounted in bearing bushes rigidly connected to chassis - Google Patents

Abstract

The steering arrangement for a perambulator, pushchair or suchlike has at least two interconnected and vertically rotationally movable axle carriers (2) mounted in bearing bushes rigidly connected to the chassis (1). The axle carriers are mounted in the bearing bushes to execute rotational movement. The rotational axes of the bearing bushes rigidly connected to the chassis, when the chassis is in use, forms with the plane of motion at right angles to the direction of motion an angle of about 90 degrees.

Description

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Steerable chassis for strollers, pushchairs, dolls’ prams and cargo transport vehicles

Short description

The invention relates to a stroller, stroller,
Doll's pram and a load transport device, the chassis (1) of which is moved by one person or several persons, at the lower end of which at least 3 axle supports (2) are vertically
Movement plane (5) are arranged, which continue at their lower vertical end, perpendicular to the horizontal wheel axles (4) for the horizontally rotatable reception of one or more running wheels (15), wherein at least 2 axle supports (2)
vertically pivotable (3) connected to the chassis (1).
According to the invention, at least two vertically pivotable axle supports (2) are coupled to one another such that the pivoting movement of a vertically pivotable axle support (2) is transmitted via the pivot transmitter (12) to the further coupled vertically pivotable axle supports (2)
at the same time is necessarily transmitted one-to-one.

Description

DE-3506077 discloses a chassis which has 4 independently vertically pivoting pivot axes connected to the chassis at its lower end, the lower extension of which forms a certain distance in the direction of travel between the pivot axis and the horizontally connected wheel axis, with which the direction of travel of the running wheels automatically aligns itself in the direction of travel when moving in the direction of travel. On each wheel axis, one or more running wheels are arranged so as to be rotatable in the direction of travel, so that with one running wheel on a wheel axis, the rotational movement plane of the running wheel in the direction of travel, the vertical pivot axis and the support point running wheel - movement plane lie on the rotational movement plane, with several running wheels on a wheel axis, the vertical pivot axis and middle support point running wheels - movement plane lie on the middle rotational movement plane of the running wheels.
Referred to by experts as a trailing axle.

Depending on the direction of travel, the rear or front vertical axles can be fixed to improve steering characteristics, aligned for straight-ahead travel.

The disadvantage of this system is that when driving straight ahead at high speed, changing road conditions and changing and uneven loads on the wheels, especially the trailing wheels, lead to uncontrollable, indefinable swivel movements around their vertical swivel axes, which can lead to an unwanted change in the direction of travel. Safe travel is therefore not possible at higher travel speeds.

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A system that is already known and implemented provides a partial solution to the problems known from DE-3506077. Two vertically pivoting trailing axles connected to the chassis are connected in the direction of travel at the front or rear. The two vertical pivot axes are connected via a lever system in such a way that both vertical pivot axes can be pivoted in parallel to each other by a limited vertical angle. Instead of the locking device for defined straight-ahead travel, a spring system is used that pivots the wheels back in a straight-ahead direction around the vertical pivot axes with a certain torque.
The disadvantage of this system is the limited swivel angle of the swivel axes connected to a lever system. The system can be moved and steered as intended if the wheel support points on the wheel's movement plane are located in the direction of travel between the person driving the vehicle and the vertical swivel axes. If the wheel support points on the wheel - movement plane are located in the direction of travel from the vertical swivel axes, the friction force between the wheel - movement plane acts as a torque on the swivel axes, turns the trailing wheels into the maximum swivel position and thus blocks straight-ahead travel.
Another disadvantage is the spring system, which turns the trailing wheels back to the straight-ahead position. The person rolling the chassis must apply a greater force to the upper end of the chassis at a right angle to the movement in order to change direction. The greater steering force required requires a greater vertical load on the two trailing wheels to increase the friction force between the running wheel and the plane of movement, or a higher coefficient of friction between the running wheels and the plane of movement, so that the spring force can be overcome to change the direction of movement.

The invention is therefore based on the object of creating a steerable chassis for strollers, children's sports buggies, doll's buggies and load transport means of the type mentioned at the beginning, which, with a simple structure, cost-effective production and reliable operation, ensures safe, stable straight-ahead travel, reversing travel, even with different properties of the surface of the travel plane, and steerability with little effort.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from this description, or may be learned by practice or use of the invention. The object, aspects and other advantages of the invention will be realized and obtained by the structure particularly pointed out in the description and the appended claims, as well as from the accompanying drawings.

In order to achieve this and other advantages in accordance with the purpose of the present invention, as implemented and described in detail, the present invention presents a steerable chassis (1) for strollers, children's sports strollers, doll's strollers and load transport means, at the lower end of which an axle support (2) is arranged at each of the corner points of the chassis (1), the lower angled extensions of which form the horizontal wheel axles (4), each of which accommodates one running wheel (15) or several running wheels (15) per angled extension so as to be rotatable in the direction of travel. At the top, devices for receiving a load-bearing means or means for receiving a stroller insert and the like can be provided, and a slider (9) connected to the chassis (1) for the movement of the chassis (1) by a person walking in an upright position. According to the invention, at least 2 axle supports (2) are provided, the upper extensions of which are accommodated in a vertically rotatable manner by the bearing bushes (14) which are firmly connected to the running gear (1), furthermore the axle supports (2) each carry a firmly connected swivel drive in the upper area centrically to the vertical swivel axis

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(13) which is connected via a swivel transmitter (12) to a further swivel drive (13) or further swivel drives (13), so that the swivel movement of an axle carrier (2) about its vertical swivel axis (3) is simultaneously transmitted 1:1 to the axle carriers (2) connected via the swivel transmitter (12). The axle carriers (2) not connected to the swivel transmitter (12) can be firmly connected to the chassis (1) for stable straight-ahead travel and cornering, or their upper ends of the axle carriers (2) are received in the associated bearing bushes (14) and aligned in the direction of straight-ahead travel by means not shown and fixed in this position.

For stable straight-ahead travel (6), the vertically pivoting axle supports (2) connected to the pivot transmitter (12) should form a gap (8) between the vertically pivoting axle (3) and the support point (7) of the wheel (15) on the travel plane (5). This means that when cornering and the steering force (11) approaches 0, the friction force in the support point (7), which acts as a torque about the vertically pivoting axle (3), automatically turns the chassis (1) back from cornering to straight-ahead travel (6). Furthermore, the vertically movable axle supports (2) are held stable in the straight-ahead position when driving straight (6).

When driving straight ahead quickly (6) and there are different frictional forces in the wheel support points (7), this would lead to uncontrolled angular movements around the vertical pivot axes (3) of the freely vertically pivoting axle supports (2). If the freely vertically pivoting axle supports (2) are connected to a pivot transmitter (12) according to the invention, the different frictional forces in the support points (7) are largely compensated, thus preventing the uncontrolled vertical angular movements of the individual wheels (15) and enabling safe straight ahead driving.
According to the invention, the vertically pivotable axle supports (2) connected to the pivot transmitter (12) can be pivoted at a vertical angle of more than 360 degrees, which enables a change in direction from a stable straight-ahead travel (6) to the opposite stable straight-ahead travel. When reversing the direction of travel, the person pushing applies a pushing force (10) opposite to the original direction of travel and additionally a small steering force (11), perpendicular to the

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Pushing force (10) on the slider (9) until the radially pivoting axle carrier (2) connected to the pivot transmitter (12) are at a slight angle to the new direction of travel. After that, when moving further without steering force (11), the vertically pivoting axle carrier (2) is rotated into a stable position for further travel due to the friction force in the support point (7) and the lever arm (8). Stable straight-ahead travel is achieved when the vertical pivot axis (3) and the support point (7) are on the middle rotational plane of the impeller (15), the rotational plane is aligned with the direction of straight-ahead travel, and the support point (7) is behind the vertical pivot axis (3) in the direction of travel.

If steerability is not desired, the free swivel angle of a swivel axle carrier (2) of the vertically swivel axle carrier (2) connected to the swivel transmitter (12) can be limited by suitable means and also set to zero. The swivel limiter can also act on the swivel transmitter (12) using suitable means (not shown). It is advantageous if the swivel limiter can be operated by the person pushing without leaving the pushing position, from the slider (9).

According to the invention, the swivel transmitter (12) must transmit the vertical rotary movement of an axle carrier (2) to the connected axle carriers (2), 1:1, simultaneously and in parallel with an unlimited angle of rotation. It is therefore advantageous to have a swivel transmitter (12) that surrounds the swivel drives (13) according to the position of the swivel drives (13) relative to one another and forms a positive, movable connection between the swivel drives (13) and the swivel transmitter (12). Chains, toothed belts and the like can be used as swivel transmitters (12) in conjunction with appropriately shaped swivel drives (13).

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Figure 1 shows a schematic representation of a children's sports buggy, at the upper end of which a slider (9) is arranged, with which a person rolls the children's sports buggy and transfers the steering movements to the chassis (1) via the slider (9), which is firmly connected to the chassis (1), and rotates the two front vertical, interconnected, pivoting axle supports (2) shown vertically in the desired curve direction. In the embodiment shown, the two rear axle supports (2) are aligned vertically when driving straight ahead and cannot be pivoted or steered via their vertical axes. Further details are shown and described in Figures 6 and 7.

Figure 2 schematically shows a load transport means at the upper end of which a slide (9) is arranged. Further details can be seen from the description of Figure 1 and Figures 6 and 7.

Figures 3 and 4 present further steerable chassis in which all axle supports (2) are arranged in bearing bushes (14) so that they can rotate vertically and the bearing bushes (14) are firmly connected to the chassis (1). All axle supports (2) which can pivot vertically in the bearing bushes (14) are connected to one another in a 1:1 manner via the pivot drives (13) and the pivot transmitter (12). This type of design enables a change of direction on the smallest plane of travel (5). The designs are not limited to the forms shown. Additional vertically pivotable axle supports (2) can be moved using the pivot transmitter (12). It can also be advantageous if further axle supports (2) which can pivot freely about their vertical axes and are not connected to the interconnected axle supports (2) via the pivot transmitter (12) are arranged on the chassis (1). Additional axle supports (2) that cannot be pivoted in the vertical direction can also be arranged on the chassis (1).

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Figure 5 is intended to explain the invention of steerable interconnected axle supports (2) in more detail using two interconnected axle supports (2).

A bearing bush (15) is arranged in a fixed position at each of the two corner points forming the chassis (1). The axle carrier (2) is mounted in the bearing bush (14) in the upper area so that it can rotate vertically and forms an angled extension at the lower end which forms the horizontal wheel axle (4) which accommodates one or more running wheels (15) so that they can rotate in the direction of travel. For improved steerability, straight-ahead travel and automatic resetting of the vertically pivoting axle carrier (2) from cornering to straight-ahead travel, the running wheel support point (7) running wheel (15) - travel plane (7) and the vertical pivot axis (3) lie on the running wheel rotation plane, with the running wheel support point (7) forming a certain caster distance (8) with the vertical pivot axis (3) of the axle carrier (2). In the upper area of the axle supports (2), a swivel drive (13) is arranged on each axle support (2) centrally to the vertical swivel axis (3), which is firmly connected to the axle support (2). The swivel drives (13) are connected to a swivel transmitter (12) in such a way that the vertical swivel movements of an axle support (2) are transmitted 1:1 to the connected axle support (2). The swivel transmitter (12) prevents the interconnected axle supports (2) from swiveling vertically relative to one another, thus enabling stable determination of the direction of travel.

Figure 6 shows the embodiment described in Figure 5, which is shown driving straight ahead (6), in curves.
The cornering is initiated by the driving person when
this in addition to the pushing force (10) on the slide (9) across the
pushing force (10) applies a small steering force (11) which is
Slider (10), which is firmly connected to the chassis (1), on the
Chassis (1). The friction force at the support point (7)
acts against the steering force (11) and pivots the axle carrier (2)
its vertical axis of rotation (3). By increasing or decreasing the
Steering force (11) increases or decreases the vertical angle of rotation
until the steering force (11) reaches the value 0 when driving straight ahead.

The design of the axle supports (2) as trailing axles in conjunction with the vertical rotational mobility, greater than 360 degrees, of the axle supports (2) connected to the swivel transmitter (12) is particularly advantageous. During the stable straight-ahead travel shown in Figure 5, the support point (7) lies between the driver and the vertical swivel axis (3) in the direction of travel. When the direction is reversed, the wheels are rotated out of the stable position of travel due to uneven road surfaces under the two support points (7) and the resulting unequal frictional forces, and due to the frictional force acting via the lever arm (8), the two interconnected axle supports (2) are rotated into the new stable position of travel, in which the support point (7) lies behind the vertical swivel axis as seen from the person driving.

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Reference marking

1 chassis 2 Axle carrier 3 Vertically pivoting axis 4 Horizontal wheel axle 5 Movement level 6 Straight ahead 7 Support point 8th Caster distance 9 Slider 10 Pushing force 11 Steering force 12 Swivel transmitter 13 Swivel drive 14 Bearing bush 15 Wheel

Details of the invention will be described in more detail below using some embodiments.

Show it:

Fig. 1 Schematic representation of a children's sports stroller with interconnected vertically pivoting axle supports.

Fig. 2 Schematic representation of a load transport device with interconnected vertically pivoting axle supports.

Fig. 3 Schematic representation of a chassis with interconnected vertically pivoting axle supports.

Fig. 4 Schematic representation of a chassis with interconnected vertically pivoting axle supports.

Fig. 5 Detailed view of 2 interconnected vertically pivoting axle supports in straight-ahead travel.

Fig. 6 Detailed view of 2 interconnected vertically pivoting axle supports during cornering.

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Claims (13)

1. Control device for a stroller, children's sports stroller, doll's stroller and a load transport means, the chassis ( 1 ) of which is moved by one person or by several people, at the lower end of which at least 3 axle supports ( 2 ) are arranged vertically to the plane of movement ( 5 ), which continue at their lower end, at right angles to the vertical connection, into horizontal wheel axles ( 4 ), for the horizontally rotatable reception of one or more wheels ( 15 ) each , characterized in that at the lower end of the chassis ( 1 ) at least 2 axle supports ( 2 ) connected to one another in a vertically rotatable manner, vertically rotatable ( 3 ), mounted in bearing bushes ( 14 ) which are firmly connected to the chassis ( 1 ), are arranged. 2. Control device according to claim 1, characterized in that the vertically rotatable axle supports ( 2 ) are rotatably mounted in the bearing bushes ( 14 ). 3. Control device according to one of claims 1 to 2, characterized in that the axes of rotation of the bearing bushes ( 14 ) which are firmly connected to the chassis ( 1 ) form an angle of approximately 90 degrees with the plane of travel ( 5 ), transverse to the direction of travel ( 6 ), when the chassis ( 1 ) is in use. 4. Control device according to one of claims 1 to 3, characterized in that each of the coupled axle supports ( 2 ) receives a pivot drive ( 13 ) in a form-fitting manner centrally to the vertical pivot axis ( 3 ). 5. Control device according to one of claims 1 to 4, characterized in that the axle supports ( 2 ) coupled to one another are connected via the pivot drives ( 13 ) to a pivot transmitter ( 12 ) partially wrapping around the pivot drives ( 13 ). 6. Control device according to one of claims 1 to 5, characterized in that the vertical pivot angle of the interconnected axle supports ( 2 ) is greater than 360 degrees. 7. Control device according to one of claims 1 to 6, characterized in that the pivot transmitter ( 12 ) transmits the angular movements of one of the axle supports ( 2 ) to the axle supports ( 2 ) connected via the pivot transmitter ( 12 ) simultaneously 1:1. 8. Control device according to one of claims 1 to 7, characterized in that the free angular movement of the interconnected axle supports ( 2 ) can be blocked for straight-ahead travel. 9. Control device according to claim 8, characterized in that the locking and the release of the angular movement can be actuated without interrupting the movement of the chassis ( 1 ). 10. Control device according to one of claims 8 to 9 , characterized in that the blocking and the release of the angular movement can be remotely controlled by the person driving the chassis (1 ) rolling forwards without leaving his drive position from the slider ( 9 ). 11. Control device according to claim 1, characterized in that the horizontal axis ( 4 ) of the axle carrier ( 2 ) forms a caster distance ( 8 ) with the vertical pivot axis ( 3 ). 12. Control device according to claim 11, characterized in that the direction of travel can be changed by the person pushing the slider ( 9 ) with a steering force ( 1 ) transverse to the direction of travel ( 6 ). 13. Control device according to one of claims 11 to 12, characterized in that when cornering with the pushing force ( 10 ) without steering force ( 11 ), the interconnected axle supports ( 2 ) acting on the slide ( 9 ), when the vertical pivot axis ( 3 ) is not locked, the frictional resistance in the support point ( 7 ) between the running wheel ( 15 ) and the plane of travel ( 5 ) automatically moves the axle supports ( 2 ) into the straight-ahead position.