Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
  • B62B3/00—Hand carts having more than one axis carrying transport wheels; Steering devices therefor; Equipment therefor
  • B62B3/001—Steering devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
  • B62B5/00—Accessories or details specially adapted for hand carts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
  • B62B2301/00—Wheel arrangements; Steering; Stability; Wheel suspension
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
  • B62B5/00—Accessories or details specially adapted for hand carts
  • B62B5/06—Hand moving equipment, e.g. handle bars
  • B62B5/063—Hand moving equipment, e.g. handle bars for low-lift hand trucks

Definitions

• the present invention relates generally to a manually controlled and maneouvered wheeled carriage or trolley, and more particularly, but not exclusively, to a steer ⁇ ing system for wheeled trolleys of the kind in which at least one of the carriage wheels is pivotally mounted on a steering column or column having a central rotational axis line, such as to be able to steer movement of the trolley during movement thereof along the trolley sup ⁇ porting surface, in accordance with the selected pivotal setting of said wheel.
• the steering column or rod is arranged to coact with a steering device which is fixedly mounted on the column.
• the inventive steering arrangement is particularly suited for trolleys of the kind in which the pivotable wheel is driven by a wheel drive arrangement connected to said wheel, wherein the steering device includes a manually gripable handle or stick located on one side of the rotational axis line.
• This handgrip will be referred to hereinafter as the stick.
• the complete function of the steering device is comparable to the function of a joy stick.
• the trolley will move behind a forwardly walking person, by virtue of a pulling force on the handle, whereas a pressure force on the handle causes the carriage to be driven in front of the walking person, in a rearward movement.
• This move ⁇ ment thus takes place with the wheels in an unstable position of alignment and the trolley can only be stee- red with great difficulty.
• One technical problem associated with a trolley of this kind which is pushed in front of a walking person in a forward direction, is one of realizing the advantages which are afforded when the steering column, by means of which the wheel or wheels are steered, and the rota ⁇ tional axis line of said steering column, extend verti ⁇ cally, so as to enable the wheel or wheels to be steered directly with the aid of an upper stick or handgrip located to one side of the geometric rotational axis of the column.
• a technical problem resides in realizing the advantages that are afforded by a vertical rotational axis with an upper support and an upper stick, thereby providing conditions such that when the stick is moved in a direction away from the rotational axis the wheels of the trolley will be set for stable wheel movement (forward movement) , whereas when the stick is moved in a direction towards the rotational axis, the trolley is driven in an opposite direction (rearwards) with the wheel settings in an unstable position of wheel alignment.
• the stick subsequent to forward movement of the trolley with the wheels positioned stably, and when desiring to reverse the trolley, the stick need only be moved towards the geometric rotational axis, whereupon the wheel drive machinery will drive the wheels in an unstable rearward direction, this wheel drive tending to rotate the wheels and the stick through 180°, therewith bringing the wheels to a stable position of alignment for smooth trolley movement.
• the stick is then again moved away from the rotational axis, wherewith the wheels are turned to a stable position in the new for ⁇ ward direction of trolley movement, this direction previously being a reverse direction, irrespective of where the person steering the trolley is located in relation to the trolley.
• a qualified technical problem is one of realizing that in the case of a trolley with which one or more of the aforesaid technical problems have been resolved, maneouvering or steering of the trolley can be greatly simplified when the stick can be moved to a positional setting forwards and backwards from a neutral position against an increasing spring force, and therewith influence the rotational speed of the wheels in a first or second direction in response to the positional setting of the stick.
• the present invention relates to an arrangement for manually steering and maneouvering a wheeled trolley along a trolley supporting surface, in which at least one of the trolley wheels or wheel pairs can be pivoted via a steering column or rod having a central geometric rotational axis line, such as to steer and move the trolley along the supporting surface in response to the positional setting of the wheel or wheel pair.
• the steering column or rod is connected rigidly to a steering device and the pivotable wheel is driven by a wheel drive mechanism connected thereto.
• the steering device has mounted thereon a manually gripable stick . which is positioned to one side of the rotational axis and which, when the trolley moves in a straight line, is located forwardly of the rotational axis line, as seen in the direction of trolley movement.
• the steering column and its rota ⁇ tional axis line extend vertically, or at least sub ⁇ stantially vertically; that the stick is pivotally, displaceably and/or tiltably attached to an upper sup- port rigidly connected to the steering column such as to be non-rotatable relative thereto; and that said drive machinery is operative to change the torque and rota ⁇ tional direction of said wheels in response to changes in the positional setting of the stick relative to said support, said setting deviating from a neutral position; and that the stick and the steering column are mounted for rotation through 360° in both directions.
• axle of the wheel is located to one side of and perpendicular to the rotational axis line, and also rearwardly behind said rotational axis line, as seen in the direction of trolley movement.
• the trol ⁇ ley includes a lower, wheeled first frame section and a second frame section which is upstanding from said first frame section, wherein two steering columns are arranged adjacent said second frame section for co-action with a respective driven and pivotable wheel and each provided with an individual joy stick function.
• the stick or sticks is/are preferably so arranged that when manually activated for forward trolley drive, the stick will be located forwardly of the rotational axis line of said steering column, as seen in the direc ⁇ tion of trolley travel, and that the stick is arranged to exercise a throttle function when moved manually in said direction, this throttle function resulting in driving of the motor in proportion to the force exerted on the stick, this being achieved by virtue of the fact that the position of the stick is communicated to a throttle device connected to the motor.
• the stick may be arranged to co-act with a position-dependent transducer or sensor, such as a sliding poten ⁇ tiometer or some corresponding device, and/or the stick may be arranged to co-act with a pressure sensor, such as a piezoelectric element.
• a position- dependent transducer or sensor such as a sliding poten ⁇ tiometer or some corresponding device
• a pressure sensor such as a piezoelectric element.
• the stick is preferably spring biased towards a neutral position.
• a telescopic device preferably adapted as handgrip, which is connected with said sticks to form a "joy stick handle assembly".
• connecting arms which are rigidly connected to and forming said hand ⁇ grips.
• the wheel can be braked electrically in response to stick movement, via said throttle device.
• Freewheel arrangements may be provided between the motor and associated wheel, for the purpose of facilitating twist ⁇ ing, slewing or like pivotal movement.
• the wheel may be arranged to rotate in a first direction when the stick is moved to a first position deviating from the neutral position, and to rotate in a second direction when the stick is moved to a second position opposite to said first position and deviating from said neutral position, thereby providing a front/back func ⁇ tion.
• the motor may be integrated with bevelled gear drive, the output shaft of which co-acts with the wheel or wheels and which is mounted for rotation with said steering column.
• a free wheel arrangement and/or the aforesaid differential arrangement is mounted between the output shaft of the bevelled gear drive and the wheel pair.
• Those advantages primarily associated with an arrange ⁇ ment for steering a moveable wheeled trolley along a trolley support surface in front of a person steering the trolley reside in the provision of conditions which enable a loaded, heavy goods trolley driven by one or more drive machines to be readily maneouvered by hand in any selec- ted direction, in the same easy manner as a much lighter trolley running on three or more wheels, e.g. a customer trolley in a departmental store.
• Figure 1 is a perspective view of a trolley having two fixed wheels positioned with their respective axles perpendicular to the longitudinal extension of the trolley, and a pivotable driven wheel
• Figure 2 is a perspective view of a four-wheeled trol ⁇ ley, having two casters and two pivotable, driven wheels, the latter in the form of wheel pairs
• Figure 3 is a perspective view of a proposed attachment of a stick to an upper support
• Figure 4 illustrates schematically a known electric coupling device operative to drive an electric motor in a first or second direction of rotation, in dependence on the positional setting of the stick;
• Figure 5 is a side view of an electric motor equipped with a worm gear and incorporating a differential and/or freewheel coupling arrangement for driving one wheel pair; and Figure 6 is a perspective view of an integrated wheel drive motor having one wheel.
• FIG. 1 is a perspective illustration of one embodiment of a steering system applied to a three-wheeled trolley 2 which can be maneouvered and steered by a single per ⁇ son along a trolley supporting surface 1 , with said person located behind the trolley.
• Two of the wheels are fixedly mounted on a load carrying platform 5 and are positioned so as to rotate parallel to the longitudinal axis of the platform 5.
• the remaining wheel 6 is pivotally mounted on a vertical steering column 7 having a central rota- tional axis 8, said wheel 6 having unlimited rotational freedom, such as to enable the trolley to be steered freely along the supporting surface 1 in a direction contingent on the angular position of said wheel.
• Steer ⁇ ing is effected by means of a steering arrangement generally referenced 9 having a function similar to the function of a joy stick, which is rigidly mounted on the steering column and which will be described in more detail hereinafter with reference to Figure 3.
• the pivotal wheel 6 is driven by an actuatable drive arrangement 10 connected to said wheel, said arrangement comprising an electric motor and associated devices connected thereto, as described in more detail herein ⁇ after with reference to Figure 6.
• the embodiment illustrated in Figure 1 also comprises a battery housing 11 which accommodates the batteries required to drive the motor 10.
• the steering arrangement 9 includes a stick 12 which is located to one side of the rotational axis line 8 and when the trolley is moved forwards in a straight line, as illustrated in Figure 1, the stick will be located forwardly of the axis line, as seen in the direction of trolley movement.
• the radial distance of the stick from the rotational axis line 8 should be greater than 3 cm but less than 20 cm, and will preferably be from 5-10 cm.
• the steering column 7 and its rotational axis line extend vertically. It lies within the scope of the invention, however, for the steering column and its rotational axis line to extend substantially vertically.
• the stick 12 is pivotably, displaceably and/or tiltably attached to an upper support 13 having the form of a round disc attached rigidly to the steering column 7.
• the drive machinery 10 is activated to drive said wheels, in response to movement of the stick relative to the support 13 to a position which deviates from a neutral position.
• the stick 12 can be moved smoothly and continuously through 360° in either direction, i.e. in the absence of a stop position, thereby enabling the stick 12 to be rotated about the rotational axis line 8 to any selected position, either directly or subsequent to a selected number of revolu ⁇ tions, without intermediate stopping.
• the axle 6a of the wheel 6 is preferably located immediately beneath or to one side of the rotational axis line 8, and then perpendicularly to said axis line immediately behind said line as seen in the movement direction F, and consequently when the trolley is moved forwards in said forward direction F the stick 12 will be located in front of the rotational axis line 8 and the wheel axle 6 will be located on or behind said axis line but in a plane coinciding therewith.
• Figure 1 illustrates one embodiment of a wheel 6.
• the wheel may also have the construction illustra ⁇ ted in Figure 5 or Figure 6.
• the wheel drive may be mounted between the two wheels of said pair.
• the stick is connected to a throttle device which is operative to activate the motor in response to the position of the stick.
• Both the throttle device and the motor are connected to the steering column 7 and participate in rotating the steering column about its longitudinal axis.
• Current is supplied via electrical sliding contacts.
• FIG 2 illustrates a second embodiment of the inven- tive arrangement, in which the steering arrangement shown in Figure 1 is duplicated.
• the load carrying platform 5 is supported by a lower wheeled first frame section 20.
• Extending upwardly from the first frame section is a second frame section 21, and two vertical steering columns 7, 7' are mounted adjacent said second frame section 21.
• Each of the steering columns 7, 7 / co- acts with a respective driven and pivotable wheel 6, 6" and are each provided with a respective stick 12, 12'.
• the wheel 6 and 6' are wheel pairs which are driven in a manner described below with reference to Figure 5.
• the frame section 20 has two caster wheels 3, 4 mounted thereto.
• the battery housing is not shown in Figure 2, for the sake of clarity.
• the sticks 12, 12' of respective handle assemblies 22 and 22' will be arranged such that upon manual ac- tivation in a common forward drive direction F they will be located in front of the respective rotational axis lines 8, 8' of the steering columns 7, 7' as seen in said forward direction; and that the sticks are opera ⁇ tive in exercising a throttle function upon said manual activation in said movement direction, such as to drive respective motors 10, 10' proportionally to the force exerted on the sticks, by virtue of the fact that move ⁇ ment of the sticks is transmitted to respective throttle devices connected to respective motors.
• the joy stick handle assembly 22, 22' which join the sticks can be manipulated to drive the motors in a common forward movement of the trolley, or may mutual ⁇ ly co-act to drive the wheels 6,6' in common, to move the trolley in the opposite direction, or may work against one another such as to cause the wheels to rotate at different speeds and in different directions.
• a common feature of the Figure 1 and Figure 2 embodi ⁇ ments is that a force applied to the stick 12, 22 in a direction away from the steering column 7 will activate the wheel drive for forward trolley movement, whereas a force applied in a direction towards the steering column 7 will activate rearward drive of the trolley.
• the stick 12 can be moved to three separate positions, a neutral position 12a, a second position 12b for driving the wheel 6 in a forward direction F, and a third position 12c in which the wheel 6 is driven for rearward trolley movement B.
• the stick 12 may also be biased towards its neutral position 12a by springs 25, 26, as illustrated in Figure 4.
• the elect ⁇ rical throttle device is operative in increasing the torque on the motor 10 in response to the distance through which the stick 12 is moved from a neutral position.
• FIG. 2 A variant of the joy stick function (12) is shown in Figure 2, in which two joy stick connecting arms 22, 22' a part of which forms the handles connecting the stick attachments 12, 12' of this embodiment have extending therebetween a hollow member 23, such as to form a tele ⁇ scopic assembly 22, 23, 22', the connecting arms forming an angle with respective handle members and the sticks in the manner illustrated in Figure 2.
• Figure 5 is a side view of a motor 10 which incorporates a worm or bevel gear drive 50, the output shaft of which co-acts drivingly with the wheel pairs 6 via a free wheel arrangement and/or a differential gear even during pivoting of the wheel pair on the steering column 7.
• a proposed differential gear 51 is based on the friction engendered between balls and two disc plates, the balls 53 being seated in holes in a driven disc plate 52.
• the disc plate 52 is driven with the aid of a belt, chain, worm or gear wheel.
• the balls 53 in the disc plate 52 are located in holes 53' disposed around a circular line and are moved round in a circular path.
• each side of the disc plate 52 Located on each side of the disc plate 52 are further discs 54, 54' which are pressed against the balls 53, to ensure that the requisite friction is obtained.
• Each of the further discs 54, 54' is provided with a circular groove 55 which serve as a running surface for the balls when the grooves face one another.
• the gear arrangement can be provided with different types of free wheel and/or differential brake or latch ⁇ ing functions of known construction.
• Figure 6 illustrated an integrated drive motor for driving a wheel 6 with the aid of an electric motor 10 and a gear arrangement 51'.
• the axle 6a of the wheel is, in this case, located in the centre of the rotational axis line 8. It will be understood that the invention is not restric ⁇ ted to the aforedescribed embodiments thereof and that modifications can be made within the scope of the inven ⁇ tive concept.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Handcart (AREA)

Applications Claiming Priority (4)

Publications (1)

Family

ID=26660249

Family Applications (1)

Country Status (3)

Families Citing this family (3)

Family Cites Families (6)

• 1989
  • 1989-06-27 EP EP19890907361 patent/EP0433291A1/de not_active Ceased
  • 1989-06-27 WO PCT/SE1989/000365 patent/WO1990000129A1/en not_active Ceased
  • 1989-06-27 AU AU38441/89A patent/AU3844189A/en not_active Abandoned

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events