Claims:WE CLAIM:

1. A collapsible load carrying trolley system 100, comprising:
- a main body frame 102;
- a load carrier frame 108 capable of carrying load;
- a handle bar 104 pivoted to the main body frame;
- atleast two wheel assembly 110 pivoted on the main body frame 102 having:
o a wheel assembly plate; and
o a 3-wheeled axle 118;
- atleast two toggle clamp 116 configured to collapse the wheel assembly;
- a plurality of magnetic lock 112 configured to fold and attach the load carrier frame 108 to the main body frame;
- a handle bar latch lock 114 configured to lock the handle bar 104 in the preferred position while carrying load;
- atleast one common wheel flap latch;
wherein, in an unfolded condition, the toggle clamp 116 is locked, the wheel assembly 110 is in a movable position, and the trolley is loaded and moveable,
and in a folded condition, the toggle clamp 116 collapses the wheel assembly inwards, locks the wheel assembly by means of said common wheel flap latch, folds the main body frame 102 and the load carrier frame 108 to attach them by means of said magnetic lock 112, and release the handle bar latch to fold the handle.

2. The collapsible load carrying trolley system 100 as claimed in claim 1, wherein said system is operable on staircases, plain and uneven surfaces.

3. The collapsible load carrying system 100 as claimed in claim 1, wherein the distance between centres of adjacent wheels in the wheel assembly 110 is less than the horizontal distance between the face of first and last risers in a staircase.

4. The collapsible load carrying system 100 as claimed in claim 1, wherein the distance between centres of adjacent wheels in the wheel assembly 110 is equal to the vertical distance between consecutive treads in a staircase.

5. The collapsible load carrying system 100 as claimed in claim 1, wherein the main body frame 102, load carrier frame 108 and handle bar 104 are made of mild/low carbon steel such as but not limited to 1018 steel.

6. A method of operation of collapsible load carrying trolley system, comprising steps of:
- releasing horizontal toggle clamps to fold both the wheel assembly 110 inwards;
- locking both the folded wheel assembly 110 by means of a common latch;
- attaching the main frame and the load carrying frame by means of a magnetic lock 112; and
- folding the handle by means of a handle bar latch lock 114.
, Description:FIELD OF THE INVENTION

[001] The present invention generally relates to a handheld load carrying trolley, more particularly relates to a collapsible load/luggage carrying trolley which can also be used in plain grounds as well as in uneven terrains and staircases.

BACKGROUND OF THE INVENTION

[002] Various manually driven load carrying vehicles such as a cart, hand truck, handcart, pushcart, strollers, chassis, and trolley are basically used for moving objects which are inconvenient for a person to carry due to heavy weight and/or size. In places like airports, stations, traveling, or shopping with heavy luggage and/or load such load carrying devices are used.

[003] Presently, the trolleys available in the market having wheels for climbing staircase are incapable of carrying heavy loads and have a complex folding mechanism, also occupying larger space that makes it inconvenient for a person to carry it along.

[004] CN106347439 discloses a hand buggy provided with a wheel combination device for climbing upstairs or carrying a load on flat ground. However, the device in combination is not capable of carrying a heavy load. Moreover, it’s folding and locking mechanism is complex and occupies larger space when not in use.

[005] US20130192907 discloses a staircase climbing vehicle with a handle for manual assistance, pair of rotatable power driven wheels, and a dual load carrying platform. However, the wheels are incapable to fold or retract when the vehicle is not in use. Also locking mechanism of the handle and wheels when the vehicle is in use is not present, which makes the system inconvenient to carry load easily and use it. Also, the system is incapable of carrying a heavy load.
[006] US20070075509 discloses a staircase climbing cart comprising wheel assembly, a pair of platforms to carry load. However, the mentioned cart is not capable to carry a heavy load and incapable to fold it wheels pivotally, making it difficult to carry along. Also, it has a complex locking mechanism.

[007] Therefore, keeping in view of the problems associated with the state of the art load carrying trolleys / carts and to further improvise their load carrying capacity alongwith folding feature of the existing staircase climbing vehicles, there is a requirement of a foldable load carrying vehicle systems which can be smoothly used in in uneven terrains and staircases without jerks and which also utilizes small storing area and are easily foldable.

OBJECTIVE OF THE INVENTION

[008] The primary objective of the present invention is to provide a collapsible load carrying trolley.

[009] Another objective of the present invention is to provide collapsible load carrying trolley which can also be used in plain grounds as well as in uneven terrains and staircases.

[0010] Another objective of the present invention is to provide collapsible load carrying trolley which can be accommodate in very small area when being folded.

[0011] Another objective of the present invention is to provide collapsible load carrying trolley which is easy to handle by the user.

[0012] Yet another objective of the present invention is to provide collapsible load carrying trolley which has a high load carrying capacity i.e. upto 80kgs.

[0013] Other objects and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawings, wherein, by way of illustration and example, the aspects of the present invention are disclosed.
SUMMARY OF INVENTION

[0014] The present invention relates to a human powered collapsible load carrying trolley system which can also be used in plain grounds as well as in uneven terrains and staircases. The disclosed trolley system, comprises of a main body frame, a load carrier frame capable of carrying load, a handle bar pivoted to the main body frame, a pair of wheel assembly pivoted on the main body frame, a toggle clamp configured to collapse the wheel assembly, a magnetic lock configured to fold and attach the load carrier frame to the main body frame, a handle bar latch lock configured to lock the handle bar in the preferred position while carrying load, and a common wheel flap latch. The wheel assembly of the system is designed to achieve stable and jerk free flight of the trolley system on the staircases or uneven surfaces. Further the system can be folded into a compact structure which makes it easy to carry it to different places.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when taken in conjunction with the detailed description thereof and in which:

[0016] Figure 1a shows the collapsible load carrying trolley system in its unfolded condition;

[0017] Figure 1b shows the collapsible load carrying trolley system in its folded condition;

[0018] Figure 2 shows three wheeled axle assembly;

[0019] Figure 3a shows going and rise of the staircase;

[0020] Figure 3b shows the locus followed by the centre of the 3 wheeled axle;

[0021] Figure 4a shows a horizontal toggle clamp;

[0022] Figure 4b shows horizontal toggle clamp when the wheel assembly is in folded condition;
[0023] Figure 4c shows horizontal toggle clamp when the wheel assembly is in unfolded condition;

[0024] Figure 5 shows a common latch;

[0025] Figure 6a shows magnetic strip attached on the frames;

[0026] Figure 6b shows the collapsed or folded frames secured by using the magnetic strips;

[0027] Figure 7a shows handle bar latch lock;

[0028] Figure 7b shows the handle bar in released position; and

[0029] Figure 8 shows various view of the collapsible system.

DETAILED DESCRIPTION OF THE INVENTION

[0030] The following description describes various features and functions of the disclosed system and method with reference to the accompanying figure. In the figure, similar symbols identify similar components, unless context dictates otherwise. The illustrative aspects described herein are not meant to be limiting. It may be readily understood that certain aspects of the disclosed system and method can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein.

[0031] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness

[0032] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.
[0033] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention.

[0034] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise

[0035] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. The equations used in the specification are only for computation purpose.

[0036] The present invention discloses a human powered collapsible load carrying trolley system 100 which is capable of carrying loads in plain grounds as well as in uneven terrains and staircases. Figure 1a shows the collapsible load carrying trolley system 100 in its unfolded condition. The system includes a main body frame 102 pivoted with a handle bar 104 which is then attached with a handle 106, a load carrier frame 108 which is capable of carrying load, atleast two wheel assembly 110, a plurality of magnetic locks 112, atleast one latch lock 114 and atleast two horizontal toggle clamp 116.

[0037] One of the main embodiment of the present invention is the construction and design of the axle 118 of the wheel assembly. The axle of the wheel assembly is designed to allow the trolley system for smooth movement in uneven terrain such as but not limited to the staircase of the buildings. The wheel assembly 110 includes a plurality of wheels rotatable around the axle. In a preferred embodiment, a three wheeled axle 118 is considered for the trolley assembly. The three wheeled axle assembly 118 is shown in figure 2. The three wheeled axle maintains the position of the trolley’s three wheels relative to each other.
[0038] In order to achieve stable and jerk free flight of the trolley system on the staircases, the distance between the centres of adjacent wheels in wheel assembly 110 is made less than the horizontal distance between the face of first and last risers in a staircase i.e. the “GOING” of the staircase. Further, the distance between centres of adjacent wheels in the wheel assembly 110 is made equal to the vertical distance between consecutive treads in a staircase i.e. the “RISE” of the staircase. The going and rise of the staircase is shown in figure 3a. The distance between the centres of adjacent wheels can be adapted considering the size standard values of “going” and “rise” of the staircase in the specific area or country. This consideration improves the ergonomics wheel assembly design and allow the jerk free and smooth handling of the trolley while on stairs. Figure 3b shows the locus followed by the centre of the 3 wheeled axle 118 while moving from one stair flight to other.

[0039] Another main embodiment of the present invention is the construction and arrangement of different components of the load carrying trolley system 100 and their collapsible feature to compact the system. Figure 1b shows the collapsible load carrying trolley system 100 in its folded condition. Figure 4a shows a horizontal toggle clamp 116 which slacks the wheel assembly 110 so that it can be folded inwards and also holds the vehicle assembly rigid while moving. Figure 4b shows horizontal toggle clamp 116 when the wheel assembly 110 is in folded condition. Also when the system is in movable condition, the horizontal toggle clamp holds the wheel assembly 110 at rigid position as shown in figure 4c. Hence, whenever, the toggle clamp 116 is locked, the wheels stay in their respective position and acts as a rigid axle assembly which makes transport of heavy loads easy. Therefore, the rigidity achieved by the horizontal toggle clamp makes the system resistant to jitter when the trolley is loaded and being used in high rise staircases.

[0040] Figure 5 shows a common latch 114 which is used to lock both the folded wheel assembly 110 which were folded by the respective horizontal toggle clamps 116. Only one of the wheel assembly is fastened with the said common latch which is folded at the last after all the other wheel assembly are folded. Hence, firstly the wheel assembly without latch is folded which is then secured and covered by another wheel assembly having common latch and thereafter the latch secures and holds the wheel assembly to which it is attached. Therefore, a single latch secures both the wheel assemblies and intact them to the main frame of the system.

[0041] After the wheels fold, the load carrier frame 108 is rotated upwards by around 90 degrees towards the main frame so that the main frame configured with magnetic strips and locks the carrier frame by magnetic force. The magnetic lock 112 is in the form of a magnetic strip that is fixed on the main frame and the load carrying frame. The magnetic strip 112 attached on the frames is shown in figure 6a. Figure 6b shows the collapsed or folded frames held together by the magnetic strips. The magnetic strips ensures constant locking while the trolley is folded and also the frame won’t rattle when being carried from one place to another in folding condition.

[0042] Further, to fold the handle of the system a handle bar latch lock 114 is present which is shown in figure 7a and 7b. Figure 7b shows how the handle bar 104 is released from the lock to make the handle fall freely and attached to the body of the main frame. The handle bar latch lock 114 also locks the handle bar in desired position while carrying the load and keeps the strength of the trolley intact.

[0043] Hence, in an unfolded condition, the toggle clamp 116 is locked, the wheel assembly 110 is in a movable position, and the trolley is loaded and moveable. While in a folded condition, the toggle clamp collapses the wheel assembly inwards, locks the wheel assembly by means of said common wheel flap latch, folds the main body frame 102 and the load carrier frame 108 to attach them by means of said magnetic lock 112, and release the handle bar latch 114 to fold the handle.

[0044] In a preferred embodiment, the various parts/components of the collapsible load carrying trolley system 100 with following specification and materials are used:

1. The main body frame 102 is made of AISI 1018 pipe with outer diameter of 25.4 mm and wall thickness of 1.6 mm.
2. The load carrier frame 108 capable of carrying load is made of AISI 1018 pipe with outer diameter of 25.4 mm and wall thickness of 1.6 mm.
3. The handle bar 104 pivoted to the main body frame is made of AISI 1018 pipe with outer diameter of 20 mm and wall thickness of 1.6 mm.
4. The wheel axle assembly has following specification:
a. The wheel assembly plate i.e. the part hinged to the main body frame is made of AISI 1018 steel plate with thickness of 4 mm;
b. The 3-wheeled axle 118 carrier plate i.e. the part on which wheels are mounted is made of AISI 4130 Steel with thickness of 2 mm; and
c. The wheels used are polyurethane (PU) wheels with bearings.
5. The toggle clamp 116 are push/pull toggle clamp of stainless steel (Grade SS 304).
6. The magnetic lock 112 are in the form of magnetic strip (Type: Ferrite Magnet).
7. The handle bar latch lock 114 are made of stainless steel (Grade SS 304).
8. The common wheel flap latch are toggle latch clamp made of stainless steel (Grade SS 304).

[0045] Further, the method of operation of collapsible load carrying trolley system, comprising steps of releasing horizontal toggle clamps to fold both the wheel assembly 110 inwards, locking both the folded wheel assembly by means of a common latch, attaching the main frame and the load carrying frame by means of a magnetic lock 112 and folding the handle by means of a handle bar latch lock 114.

[0046] Consequently, considering all the above embodiments, the present invention provides a human powered collapsible load carrying trolley system 100. The different views of the collapsible system is shown in figure 8. The collapsible load carrying trolley system is capable of carrying loads of up to 80kgs safely in plain grounds as well as in uneven terrains and staircases. Further, the system requires very small area when in folded condition and hence can be carried from one place to another.

[0047] While the present invention has been described with reference to one or more preferred aspects, which aspects have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, such aspects are merely exemplary and are not intended to be limiting or represent an exhaustive enumeration of all aspects of the invention. The scope of the invention, therefore, shall be defined solely by the following claims. Further, it will be apparent to those of skill in the art that numerous changes may be made in such details without departing from the spirit and the principles of the invention.