WO2022094650A1

WO2022094650A1 - Trolley control mechanism for a dynamic steer trolley

Info

Publication number: WO2022094650A1
Application number: PCT/AU2021/051283
Authority: WO
Inventors: Isaac Sheppard
Original assignee: Isaac Sheppard
Priority date: 2020-11-03
Filing date: 2021-11-01
Publication date: 2022-05-12
Also published as: AU2021376440A1

Abstract

The present invention relates to manoeuvrability and control-ability of shopping trolleys of all kinds, and mechanisms thereof.

Description

TROLLEY CONTROL MECHANISM FOR A DYNAMIC STEER TROLLEY

FIELD

The present invention relates to manoeuvrability and control-ability of trolleys of all kinds, and mechanisms thereof.

BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art.

Conventional trolleys such as the ones used for shopping, airports, hospitals beds and ambulance stretchers and the like have locking mechanisms that allow locking of the trolley wheels in a forward-rearward position. These known mechanisms allow a limited range of lockability, requiring caster wheels to be near specifically straight forward or backwards, before they are able to be locked, this reduces usability considering the dynamics of the trailing axle caster wheel design. The advantages herein increase the degrees of engagement, allowing the user to align trailing axle caster wheels at a wider range of degrees before they are specifically locked forward or backwards, with little strain on the operator.

Further disadvantages of known locking mechanisms only allow locking of only one wheel of the trolley. This can be a problem if the single locked wheel is lifted off the ground from uneven terrain. This scenario could lead to losing control of the locked front wheel and could create a dangerous situation, such as resulting in the trolley dashing on something or someone or the trolley tripping over. These aspects would not give the user confidence on uneven terrain. Moreover, the locking mechanisms that are currently available do not ensure that the caster wheels are locked only in a predetermined position, such as in a forward or rearward position. Some of the existing mechanisms require the user to consistently apply a positive pressure with both the hands to ensure that the wheels are in an unlocked position. None of these known mechanisms allow lateral movement of the trolley from a stationary position when desired, thus, limiting manoeuvrability of the trolley in a stationary position.

User requirements change depending on available space and load. From tight spaces with heavy traffic and/or tight corners, four-wheel pivot-ability is ideal for full manoeuvrability.

Where there is enough space and the trolley is equipped with heavy loads, front wheel lock-ability is desired, to gain control by pivoting from the

SUBSTITUTE SHEET (RULE 26) front of the trolley, using the length of the trolley as leverage, to resist inertia and gravity around corners and on uneven ground. Full manoeuvrability is desired in a stationary position, as the user can easily and quickly move the trolley aside if there are other obstacles to manoeuvre around.

Trolleys related to environments, such as; airports, hospitals and ambulance stretchers, may incorporate various combinations of locking wheels, utilising the unique design features set forth herein.

Hence, a trolley control mechanism is sought, which ameliorates the abovementioned shortcomings as well as fulfils the abovementioned requirements.

OBJECTS

Some of the objects of the present disclosure, which at least one embodiment satisfies, are as follows:

A primaij object of the present disclosure is to provide a trolley control mechanism for a trolley.

Another object of the present disclosure is to provide a trolley control mechanism for a trolley, which provides desired controllability and manoeuvrability of a trolley.

Yet another object of the present disclosure is to provide a trolley control mechanism for a trolley, which allows lockability of wheels as well as all-wheel pivotability.

Still another object of the present disclosure is to provide a trolley control mechanism for a trolley, which can be easily retrofitted to an existing trolley.

Yet another object of the present disclosure is to provide a trolley control mechanism for a dynamic steer trolley, which is compact.

Still another object of the present disclosure is to provide a trolley control mechanism for a trolley, which is robust.

Yet another advantage allows two wheels to be locked simultaneously with only one locking mechanism, best suited, yet not limited to; the shopping trolley environment. The design features herein, may incorporate multiple variations of similar parts to lock multiple wheels, involving more than one locking mechanism, potentially suited for other environments other than the shopping industry.

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SUBSTITUTE SHEET (RULE 26) Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.

Summary of Invention

The present invention provides a trolley assembly comprising:

(i) upper components attached to a trolley handle;

(ii) lower components capable of reliably locking wheels straight forwards or backwards;

(iii) a locking shaft mechanism enabling, but not limited to two wheels to be locked simultaneously forward or backward; and

(iv) cable system/s connecting the upper and lower components wherein the assembly provides a user full control and manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels of the trolley and allowing the user to know when the wheels are locked or are ready to be locked.

Preferably, the upper components comprise a cable system, a hand lever, a mount either end of the hand lever.

Preferably, the lower components comprise a locking shaft, a lower mount at either end of the locking shaft and caster wheel locking disc frame assemblies.

Preferably, the locking shaft comprises two locking tabs, a cable lever and cable pin wherein the locking shaft enables, but not limited to, both front wheels to be locked straight simultaneously forwards or backwards.

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SUBSTITUTE SHEET (RULE 26) Preferably, the locking disc frame assemblies comprise a locking disc, a hook and two reinforced ridged uprights.

Preferably, the locking disc is a circular disc with preferably two slots formed thereon, 180° apart and a locking tab of the locking shaft which engages in either of these slots of the disc.

Preferably, the upper component assembly further includes a resilient member.

Preferably, the locking tabs include a bearing housing integrated therewithin, and bearings configured to minimise friction between the locking discs and the locking tabs, to alleviate crab walking while the locking tabs are yet to be engaged and before the wheels are straight.

Preferably, the user maintains full manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels of the trolley and allowing the user to know when the wheels are locked or are ready to be locked.

Preferably, the wheels are unlocked in a resting position and engaged for locked wheel control.

Preferably, the trolley is adapted to be attached to either hand lever mount to allow the user to optionally choose to lock the hand lever in a locked wheel position.

In another aspect, the present invention provides a method of controlling and locking a trolley using the trolley assembly according to the present invention as hereinbefore described.

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SUBSTITUTE SHEET (RULE 26) Preferably, the user maintains full manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels of the trolley and allowing the user to know when the wheels are locked or are ready to be locked.

Preferably, the trolleys are used in shopping, hospital beds, ambulance stretchers, airports and the like.

Preferably, the wheels are unlocked in a resting position and optionally engaged for locked wheel control.

Preferably, the trolley is adapted to be attached to either or both hand lever mounts to allow the user to optionally choose to lock and maintain the hand lever in a locked wheel position.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWING

Figure 1 illustrates a schematic view of a trolley control mechanism for a trolley according to the present disclosure;

Figure 2 shows an isometric view of an upper component assembly of the trolley control mechanism of Figure 1 ;

Figure 3 illustrates an exploded view of the upper component assembly of Figure 2;

Figure 4 shows another view of a key-key-way pair along with a hand lever, an upper primary mount and an upper cable mount;

Figure 5 illustrates an operative and an inoperative state in a side view of the upper component assembly of Figure 2;

Figure 6 shows an isometric view of a lower component assembly of the trolley control mechanism of Figure 1 with caster wheels of the trolley;

Figure 7 illustrates an exploded view of the lower component assembly of Figure 6 without the caster wheels;

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SUBSTITUTE SHEET (RULE 26) Figure 8a illustrates a side view of a caster wheel locking disc frame assembly mounted on a caster wheel;

Figure 8b illustrates an isometric view of the caster wheel locking disc frame assembly;

Figure 8c illustrates profile of ridges of a caster wheel frame upright;

Figure 9 illustrates a side view of the lower component assembly with a cable system in an operative configuration;

Figure 10a illustrates a top view of a locking disc with a magnified view of a slot therein;

Figure 10b illustrates a sectional view of a three-dimensional shape in the locking disc;

Figure 10c illustrates a front view of the locking disc; and

Figure lOd illustrates an isometric view of the locking disc with a magnified view of a square wall in the slot therein.

LIST OF REFERENCE NUMERALS

1000 Trolley control mechanism of the present disclosure

100 Upper component assembly

1 Hand lever

2 Upper cable pin

3 Key-way mechanism cover

4 Key on hand lever

5 Hand lever Primary bush

5a Key-way on hand lever primary bush

6 Upper primary mount

7 Upper cable mount

8 Upper secondary bush

6

SUBSTITUTE SHEET (RULE 26) Upper secondary mount

Lower component assembly

Locking shaft

Locking tab

Cable lever

Lower cable pin

Lower primary mount

Lower primary bush

Locking shaft cable lever

Lower secondary mount

Lower secondary bush

Locking disc

Caster wheel frame uprights

Caster wheel frame hook

Locking disc slot

Caster wheel frame upright profile

Square wall (in locking disc design)

Angled shape in locking disc design

Low friction surface

Cable system

Cable system guard

Resilient member

Bearing

Trolley

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SUBSTITUTE SHEET (RULE 26) 310 Trolley handle frame

315 Trolley handle

320 Caster wheel

322 Caster wheel frame

DETAILED DESCRIPTION

Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing, in a configuration related to the shopping trolley environment, various combinations may be more related to trolleys in alternative industries.

Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “comprises”, “comprising”, “including” and “having” are open-ended transitional phrases and therefore specify the presence of stated features, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, operations, elements, components, and/or groups thereof.

When an element is referred to as being “mounted on”, “engaged to”, “connected to” or ‘coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.

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SUBSTITUTE SHEET (RULE 26) The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.

Terms such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.

Conventional mechanisms for controlling a dynamic steer trolley such as the ones used for shopping, hospitals, ambulances and airports and the like, become difficult to control on uneven terrains. This is because most of the conventional mechanisms have an arrangement which limits the range of lockability, and locks rotation of only one wheel out of the four. A mechanism for controlling a dynamic steer trolley is sought, which allows the trolley to be easily and safely manoeuvred in a variety of situations such as in tight spaces, in case of heavy loads, in case where other users need to get past, and so on.

The trolley control mechanism 1000 for a dynamic steer trolley of the present disclosure resolves the above-mentioned issues. Figure 1 illustrates a schematic view of a trolley control mechanism 1000 according to the present disclosure. The mechanism 1000 can comprise of an upper component assembly 100 and a lower component assembly 200, connected through a cable system 27. The cable system 27 can be covered with a cable guard 28. The upper component assembly 100 can be attached to the trolley handle frame 310. The lower component assembly 200 can be disposed of in the vicinity of the caster wheels 320.

Figure 2 shows an isometric view of an upper component assembly of the trolley control mechanism of Figure 1. The component assembly can comprise a hand lever

1. an upper primary mount 6, and an upper secondary mount 9. The hand lever 1 can be pivotably mounted between the upper primary mount 6 and the upper secondary mount 9, wherein the mounts 6 and 9 can be attached on the trolley handle frame 310.

Figure 3 illustrates an exploded view of the upper component assembly of Figure

2. In an embodiment, a key-key-way pair 4-5a can be provided between the hand lever 1 and the upper primary mount 6. Figure 4 shows another view of the key-

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SUBSTITUTE SHEET (RULE 26) key- way pair 4, 5a along with the hand lever 1, the upper primary mount 6 and an upper cable mount 7. The key 4 can be provided, by machining or welding or any other method, at the end of the hand lever 1 with the mating key-way 5a provided in a bush 5 wherein the bush 5 can be fixed in the upper primary mount 6. Alternatively, key-way 5a can be provided on the upper primary mount side with the key 4 provided on the hand lever side. An upper cable mount 7 can be configured to be attached with the upper primary mount 6. The upper cable mount 7 can receive a portion of the cable system 27. One end of the cable of the cable system 27 can be coupled with an upper cable pin 2 which can be provided, by welding or any other similar other method, at one end of the elongated handling portion of the hand lever 1. The other end of the hand lever 1 can be inserted into a secondary bush 8 which can be fixed in the upper secondary mount 9. The upper component assembly further includes a resilient member 30 which is integrated into the secondary bush 8, which holds positive pressure against the hand lever, to ensure that the lever is held against the key way mechanism. In an embodiment, the resilient member 30 is a spring component.

Figure 6 shows an isometric view of the lower component assembly 200 of the trolley control mechanism 1000 of Figure 1 with caster wheels 320 of the trolley. The lower component assembly 200 can comprise of a locking shaft 10, a lower primary mount 14, a lower secondary mount 17 and a caster wheel locking disc frame assembly.

Figure 7 illustrates an exploded view of the lower component assembly of Figure 6 without the caster wheels. The locking shaft 10 can be provided with two locking tabs 1 1 (one for each front caster wheel 320), a cable lever 12 and a lower cable pin 13 as shown in Figure 7. The locking shaft 10 can be pivotably suspended between a lower primary bush 15 and a lower secondary bush 18. The locking tabs 11 include a bearing housing integrated therewithin, and bearings 40. The bearings 40 are configured to minimise friction between the locking disks 19 and locking tabs 11, to alleviate crab walking while the locking tabs 11 are yet to be engaged and before the wheels are straight.

The locking disc frame assembly can be configured with the caster wheel 320 as illustrated in Figure 8a. Figure 8b illustrates an isometric view of the caster wheel locking disc frame assembly. Figure 9 illustrates a side view of the lower component assembly with the cable system in an operative configuration. Each of

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SUBSTITUTE SHEET (RULE 26) the two locking disc frame assemblies can comprise a locking disc 19, a hook 21 and two reinforced ridged uprights 20. Figure 8c illustrates the profile of the reinforced ridges of the caster wheel frame upright. The hook 21 can hook the locking disc 19 onto the front of the caster wheel frame 322 and can pivot around the caster wheel 320 to allow the ridged uprights 20 to be bolted, welded or integrated into the caster wheel frame 322. which may be through integrated holes in the uprights 20, that utilise the axle bolt to fix the locking disc frame 322 to the caster wheel 320.

Figures 10a, 10b, 10c and lOd illustrate details of the locking disc 19 of the present disclosure. The locking disc 19 can be a circular disc with a preferable two slots 22 formed thereon, 180° apart. The locking tab 11 of the locking shaft 10 can engage in either of these slots 22 of the disc 19. The locking disc 19 can incorporate a three- dimensional shape 25 in the area of the disc that allows the locking tabs 11 to slide towards the slot 22 formed on the disc 19. The angled shape 25 allows the locking tab 11 to slide along a low-friction surface 26, which increases the user’s capabilities to engage the front wheels towards a locked straight position. This shape 25 creates a mechanical means to reduce the load on the user’s hands, even when a lot of weight is placed in the trolley. The shape 25 gives a feeling akin to a hydraulic mechanism while engaging the front wheels towards being locked straight forwards or backwards. The angled shape 25 of the entry section of the locking disc 19 slopes down towards the locking disc slot 22, which incorporates a small section 24 that is square with the straight caster wheel position. This small square wall section 24 allows the user to keep the wheels locked easily without an effort. The overall design of the locking disc 19 also allows the locking tabs 11 to disengage easily from the locking slot 22. The design allows the positive weight of the hand lever 1 and the non-flexible cable of the cable system 27 to automatically disengage the locking shaft 10, when the hand lever 1 is not being pulled, additionally a known spring configuration may be integrated into the locking shaft 10 to assist with disengagement, depending on the load bearing requirements of the trolley.

The locking disc 19 and the locking tabs 11 can integrate the low-friction surface 25, 26 between the surfaces that contact between one another, including the perimeter of the locking disc where the locking tabs 11 can freely slide along if attempting to engage the locking mechanism, when the locking slot 22 is not 11

SUBSTITUTE SHEET (RULE 26) aligned. This increases the assisted feel of locating the locking slots 22, and allows the locking tabs 11 to slide along the outside perimeter of the locking disc 19 when the locking tabs 11 have not engaged, thus reducing the chances of the trolley “crab walking” sideways if the hand lever 1 is pulled when the locking tabs 11 are not engaged with the entry point of the locking slots 22. This allows the trailing axle caster wheel to still rotate even when pressure is applied to the outside perimeter 26 of the locking disc 19 by the locking tabs 11 by the user.

The cable system 27 can have a low-friction design, creating the connection between the hand lever 1 and the lower locking mechanism. The connection between the cable pins 2 and 13 of the cable system 27 needs a low friction configuration, while maintaining a tight tolerance enough to be able to push or pull the hand lever effortlessly.

The upper and lower cable mounts 7 and 17 are designed to create as little friction as possible, relative to the rotation of both the hand lever 1 and the locking shaft cable lever 16.

The outer cable of the cable system 27 is best situated inside the lower trolley frame, as it is protected by the trolley frame if it hits a wall or curb. However, as the trolleys are stacked together, the cable can be damaged. To overcome this situation, integrating an outer guard 28 prevents the cable system 27 from being damaged in the stacking process. The protective guard 28 can also protect the cable system 27 in the cage of the trolley.

The configuration lower component assembly 200 is compact and robust, capable of reliably locking wheels straight forwards or backwards, with minimal effort to operate when the trolley is pushed roughly straight forwards or backwards. The wheels can also be locked in opposite directions if one wheel becomes raised on uneven terrain, when both wheels fail to track together.

Figure 5 illustrates an operative and an inoperative state in a side view of the upper component assembly of Figure 2. The hand lever 1 of the upper component assembly 100 can be mounted in a position that minimizes rotational drag of the hand lever 1 relative to the trolley handle 315, and at a height and an angle of an average person’s hand and arm position. The upper bushes 5, 8 give a low-friction configuration enabling smooth engagement and disengagement of the lower locking mechanism using the hand lever 1. The key-key-way pair 4, 5a can limit the angle

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SUBSTITUTE SHEET (RULE 26) of rotation of the hand lever 1 thereby preventing the lever 1 from squishing the user's fingers between the hand lever 1 and the trolley handle 315. The key-keyway pair 4, 5a can also act to alleviate stress on the lower locking shaft 10 and the cable lever 12. In addition, the key-key-way pair 4, 5a can stop the lever 1 from being pushed in the reverse direction of the engagement direction, which protects the preferable non-flexible cable from being bent backwards unfavourably. Also, the key-key-way pair 4, 5a can hold the hand lever 1 in a stationary position that is off-centre of being level, thus using gravity to create positive pressure between the hand lever 1 and the lower locking mechanism, this may be assisted by integrating a known spring system to the locking shaft 10. Integrating a plate 3 to the hand lever 1 that can sit against the key 4 would prevent fingers from being pinched.

The upper primary mount 6 can integrate a cable mount 7 that would allow the cable system 27 to be mounted in an adjustable configuration.

The cable mount 7 can be positioned to minimise the friction between the inner and outer cable, as the invention would work best with a non-flexible cable. This can be designed around the rotation arc of the hand lever 1 and upper cable pin 2.

The mechanism of the present disclosure described above is an ideal mechanism for shopping, airports, hospitals and ambulance environments, because the mechanism 1000 can give the user full manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels. Even if the area is too tight for dynamic locked wheel steering or if there is a trolley traffic jam, full manoeuvrability can be guaranteed. Moreover, the mechanism gives the user a direct feedback allowing the user to know when the wheels arc locked or arc ready to be locked. The mechanism can allow the user to engage and lock the wheels easily, when pushed roughly straight forwards or backwards, even with only using one finger to engage the locking mechanism. This mechanism can be compact, robust and can reinforce the front caster wheel frames 322. It can quickly be installed to an existing trolley, or the same mechanism can be incorporated to the trolley manufacturing process, reducing the number of pails needed to create this design configuration.

The wheel locking components can be adapted to varying trolley applications which may involve multiple locking shafts and looking shaft mounts. attached to each desired wheel frame. For applications better suited for rough terrain, where a single locking shaft hinders terrain

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SUBSTITUTE SHEET (RULE 26)

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular' embodiment are generally not limited to that particular embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

TECHNICAL ADVANCEMENTS

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a trolley control mechanism for a rear steer trolley which can:

• reinforce the front caster wheel frames;

• be easily retrofitted to an existing trolley; or integrated into the trolley manufacturing process

• allow manoeuvring the trolley laterally from a stationary position;

• give the user a feedback of the locking state of the wheels;

• capability of locking two wheels with only one mechanism;

• be safe to operate;

• be easy to operate;

• be compact; and

• be robust.

The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments

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SUBSTITUTE SHEET (RULE 26) herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and arc intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

Any discussion of materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein,

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SUBSTITUTE SHEET (RULE 26) whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

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SUBSTITUTE SHEET (RULE 26)

Claims

The claims defining the invention are as follows:

Claim 1

A trolley assembly comprising:

(i) upper components attached to a trolley handle;

Claim 2

The trolley assembly according to claim 1 wherein the upper components comprise a cable system, a hand lever, a mount either end of the hand lever.

Claim 3

The trolley assembly according to claim 1 wherein the lower components comprise a locking shaft, a lower mount at either end of the locking shaft and caster wheel locking disc frame assemblies. Claim 4

The trolley assembly according to claim 3 wherein the locking shaft comprises two locking tabs, a cable lever and cable pin wherein the locking shaft enables, but not limited to, both front wheels to be locked straight simultaneously forwards or backwards.

Claim 5

The trolley assembly according to claim 3 wherein the locking disc frame assemblies comprise a locking disc, a hook and two reinforced ridged uprights.

Claim 6

The trolley assembly according to claim 5 wherein the locking disc is a circular disc with preferably two slots formed thereon, 180° apart and a locking tab of the locking shaft which engages in either of these slots of the disc.

Claim 7

The trolley assembly according to any one of claims 1 -6 wherein the upper component assembly further includes a resilient member.

Claim 8

The trolley assembly according to any one of claims 1 -7 wherein the locking tabs include a bearing housing integrated therewithin, and bearings configured to minimise friction between the locking discs and the locking tabs, to alleviate crab walking while the locking tabs are yet to be engaged and before the wheels are straight. Claim 9

The trolley assembly according to any one of claims 1 -8 wherein the user maintains full manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels of the trolley and allowing the user to know when the wheels are locked or are ready to be locked.

Claim 10

The trolley assembly according to any one of claims 1 -9 wherein the wheels are unlocked in a resting position and engaged for locked wheel control.

Claim 11

The trolley assembly according to any one of claims 1 -10 wherein the trolley is adapted to be attached to either hand lever mount to allow the user to optionally choose to lock the hand lever in a locked wheel position.

Claim 12

A method of controlling and locking a trolley using the trolley assembly according to any one of claims 1 to 11 .

Claim 13

The method according to claim 12 wherein the user maintains full manoeuvrability in its unlocked state by allowing free pivoting of all four caster wheels of the trolley and allowing the user to know when the wheels are locked or are ready to be locked.

19 Claim 14

The method according to any one of claims 12 or 13 for use of trolleys in shopping, hospital beds, ambulance stretchers, airports and the like.

Claim 15 The method according to any one of claim 12 to 14 wherein the wheels are unlocked in a resting position and optionally engaged for locked wheel control.

Claim 16

The method according to any one of claims 12 to 15 wherein the trolley is adapted to be attached to either or both hand lever mounts to allow the user to optionally choose to lock and maintain the hand lever in a locked wheel position.

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