Claims:WE CLAIM:
1. A manhole cover (100) comprising:
a first part (110);
a second part (120) arranged in a spaced apart configuration with said first part (110); and
a plurality of ribs (130) extending between said first part (110) and said second part (120), said ribs (130) being formed integral with said first part (110) and said second part (120), said ribs (130) having a tapered structure.
2. The manhole cover (100) as claimed in claim 1, wherein said ribs (130) are parallel to each other.
3. The manhole cover (100) as claimed in claim 1, wherein said ribs (130) are radially arranged between said first part (110) and said second part (120).
4. The manhole cover (100) as claimed in claim 1, wherein each of said first part (110), said second part (120) and said ribs (130) is of a composite material.
5. The manhole cover (100) as claimed in claim 4, wherein said composite material includes:
a base material selected from the group consisting of polypropylene, polyethylene, nylon, polyethylene terephthalate, and acrylonitrile butadiene styrene and any combinations thereof; and
fibers selected from the group consisting of glass fibers, carbon fibers, and any combinations thereof.
6. The manhole cover (100) as claimed in claim 1, wherein the ratio of perimeter of said first part (110) to thickness of said ribs (130) ranges from 100 to 1000.
7. The manhole cover (100) as claimed in claim 1, wherein said plurality of ribs (130) includes a set of first ribs (135) configured parallel to each other and at least one second rib (140) configured orthogonal to said first ribs (135).
8. The manhole cover (100) as claimed in claim 1, wherein thickness of each of said ribs (130) decreases along a radial direction of said cover (100).
9. The manhole cover (100) as claimed in claim 1, wherein each of said ribs (130) has constant thickness.
10. The manhole cover (100) as claimed in claim 1, wherein each of said ribs (130) has varying thickness along the length thereof.
11. The manhole cover (100) as claimed in claim 1, wherein said cover (100) includes at least one intermediate part (115) arranged between said first part (110) and said second part (120).

Dated this 20th day of May, 2019

FOR THE SUPREME INDUSTRIES LTD.
BY THEIR AGENT

GIRISH VIJAYANAND SHETH IN/PA- 1022
KRISHNA & SAURASTRI ASSOCIATES LLP
, Description:FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
THE PATENTS RULE, 2003
COMPLETE SPECIFICATION
[See Section 10, Rule 13]

A MANHOLE COVER

THE SUPREME INDUSTRIES LTD., A COMPANY INCORPORATED UNDER THE INDIAN COMPANIES ACT, 1913, WHOSE ADDRESS IS 4THFLOOR, “ANTARIKSHA SIGNATURES”, BEHIND NYATI BULILDING, RADHA CHOWK, NEAR RADHA HOTEL 105/1/1/4, BANER, PUNE- 411045, MAHARASHTRA. INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

TECHNICAL FIELD OF THE INVENTION
The present invention relates to the field of manhole covers.
BACKGROUND OF THE INVENTION
A manhole is an opening provided to access underground confined spaces such as sewers or underground chambers. A cover is provided on the manhole to prevent pedestrians/vehicles from accidently entering the manhole. The cover also prevents unauthorized access to the manhole. Conventionally, the manhole covers are made of cast iron, concrete or composite materials. However, the concrete manhole covers are heavy in weight which makes it difficult for a person to move them. Further, the manhole covers of cast iron are susceptible to corrosion and wear. The composite manhole cover overcomes drawbacks of the manhole covers of cast iron or concrete. However, the manhole covers made of composite materials, such as fibre reinforced plastic (FRP), consumes a lot of time for manufacturing. Thus, use of FRP as a material makes the manufacturing of a manhole cover laborious and complex.
Therefore, there is felt a need of a manhole cover that alleviates the aforementioned drawbacks associated with conventional manhole covers.
SUMMARY OF THE INVENTION
The present disclosure envisages a manhole cover. The cover comprises a first part, a second part arranged in a spaced apart configuration with the first part, and a plurality of ribs. The ribs extend between the first part and the second part. The ribs are formed integral with the first part and the second part.
In an embodiment, the ribs are parallel to each other. In another embodiment, the ribs are radially arranged between the first part and the second part.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A manhole cover, of the present disclosure, will now be described with reference to accompanying drawing, in which:
Figure 1 illustrates an isometric view of the manhole cover, in accordance with an embodiment of the present disclosure;
Figure 2 illustrates a side view of the manhole cover of figure 1;
Figure 3 illustrates a sectional view of the manhole cover of figure 1, wherein the section is taken along a longitudinal plane of the cover;
Figure 4 illustrates another sectional view of the manhole cover of figure 1, wherein the section is taken along a lateral plane of the cover;
Figure 5 illustrates an isometric view of the manhole cover, in accordance with another embodiment of the present disclosure;
Figure 6 illustrates another sectional view of the manhole cover of figure 5, wherein the section is taken along a lateral plane of the cover;
Figure 7 illustrates an isometric view of the manhole cover, in accordance with yet another embodiment of the present disclosure;
Figure 8 illustrates a sectional view of the manhole cover of Figure 7, wherein the section is taken along a lateral plane of the cover; and
Figure 9 illustrates an isometric view of a frame.
LIST OF REFERENCE NUMERALS
100 – Cover
110 – First part
115 – Intermediate part
120 – Second part
130 – Ribs
135 – First ribs
140 – Second rib
145 – Mounting arrangement
150 – Frame
155 – Bumps
160 – Receiving arrangement
DETAILED DESCRIPTION OF THE INVENTION
Although specific terms are used in the following description for sake of clarity, these terms are intended to refer only to particular structure of the invention selected for illustration in the drawings, and are not intended to define or limit the scope of the invention.
References in the specification to “one embodiment” or “an embodiment” mean that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
The present disclosure envisages a manhole cover which is light in weight, easy to manufacture, and has high strength to weight ratio.
The manhole cover, of the present disclosure is now described with reference to Figure 1 to Figure 9 of the accompanying drawing.
Referring to Figure 1 to Figure 8, a manhole cover (100) is shown.
The manhole cover (100) comprises a first part (110), a second part (120), and a plurality of ribs (130).
The first part (110) forms a top portion of the cover (100) and the second part (120) forms a bottom portion of the cover (100). The second part (120) is arranged in a spaced apart configuration with the first part (110). A plurality of ribs (130) extends between the first part (110) and the second part (120). The first part (110), the second part (120), and the ribs (130) are integral with each other, and the cover (100) is formed as a single body.
The first part (110) and the second part (120) can have any suitable geometrical shape. In an embodiment, the first part (110) and the second part (120) are circular in shape with identical dimensions. In another embodiment, the first part (110) and the second part (120) are rectangular or square in shape. In yet another embodiment, the first part (110) and the second part (120) have spacing between them which is equal to the height of the ribs (130).
The cover (100) comprises at least one intermediate part (115). The intermediate part (115) is arranged between the first part (110) and the second part (120), and is parallel with the first part (110) and the second part (120). The ribs (130) integrally extend between the first part (110) and the intermediate part (115), and between the intermediate part (115) and the second part (120). The intermediate part (115) improves the strength of the cover (100). Further, the intermediate part (115) enables to increase the height of the manhole cover (100). In case the cover (100) is manufactured using an injection moulding process, there is limit on the height on the ribs (130) with respect to the base thickness of the ribs (130). In injection moulding process, the height of the ribs (130) can only be kept around 5 to 6 times the base thickness, i.e., the thickness of the second part (120). For example, if the thickness of the second part (120) is 6 mm, the height of the ribs (130) can only be limited to 30 to 40 mm. This limits overall height of the cover (100). However, by addition of the intermediate part (115), the height of the ribs (130) can be increased as the base of the ribs (130) is now the intermediate part (115) or the second part (120). Thus, multiple sections of the ribs (130) can be formed between the intermediate part (115) and the first part (110) or the second part (120), thereby increasing overall height of the cover (100).
Depending upon the required height of the cover (100), multiple intermediate parts (115) can be arranged between the first part (110) and the second part (120).
As shown in Figure 1 to Figure 8, the ribs (130) are arranged in a spaced apart configuration. The spacing between the ribs (130) is determined as per the manufacturing process requirement and strength to be achieved.
In an embodiment, the ribs (130) are arranged parallel to each other (as shown in Figure 1 to Figure 6). In another embodiment, the ribs (130) are radially arranged between the first part (110) and the second part (120) (as shown in Figure 7 and Figure 8). In yet another embodiment, the ribs (130) are arranged perpendicular to each other. In yet another embodiment, the ribs (130) are arranged such that each rib (130) makes a convenient angle with adjacent ribs (130). In yet another embodiment, the ribs (130) are arranged such that each rib (130) makes any other suitable configuration with other ribs (130).
In another embodiment, the plurality of ribs (130) includes a set of first ribs (135) and at least one second rib (140). The first ribs (135) are configured parallel to each other, whereas the second rib (140) is configured orthogonal to the first ribs (135) (as shown in Figure 4 and Figure 6). In yet another embodiment, the first ribs (135) are radially arranged between the first part (110) and the second part (120), whereas the second rib (140) is configured along a radial plane of the first ribs (135) and parallel to the first part (110) and the second part (120). In yet another embodiment, the cover (100) includes a plurality of second ribs (140). In another embodiment, the second rib (140) is positioned centrally with respect to the first part (110) and the second part (120).
The thickness of the ribs (130) is determined considering the estimated load subjected on the cover (100).
In an embodiment, the ribs (130) have constant thickness along the length thereof. More specifically, the ribs (130) have constant thickness along radial direction of the cover (100).
In another embodiment, the ribs (130) have varying thickness along the length thereof. The thickness of the ribs (130) decreases along the radial direction of the cover (100). More specifically, the thickness of a rib (130) at the central portion of the cover (100) is more than the thickness of the same rib (130) at remaining portion of the cover (100). The ratio of thickness of a rib (130) at the central portion of the cover (100) to the thickness of the same rib (130) at the periphery of the cover (100) ranges from 1.1 to 3. As the maximum load is applied at the central portion of the cover (100), the portion of each rib (130) at the central portion of the cover (100) has thickness higher than the thickness of the portion of same rib (130) at portion other than the central portion of the cover (100). This improves load bearing capacity of the cover (100) without substantial increase in the weight of the cover (100).
Further, the ratio of perimeter of the first part (110) to thickness of the ribs (130) is in the range of 100 to 1000.
In an operative configuration, the first part (110) and the second part (120) are horizontally placed, whereas the ribs (130) are orthogonal to the planes of the first part (110) and the second part (120). Thus, the cover (100) has a ‘I’ shaped cross-section, which results in higher strength to weight ratio as compared to conventional manhole covers having a ‘T’ shaped cross-sectional shape.
Table – 1
Weight Size (Diameter) Load bearing capacity of the cover of the present disclosure for particular material and particular manufacturing process
3 Kg 355 mm 3 ton
6 Kg 450 mm 10 ton
6 Kg 600 mm 7 ton
It is evident from Table-1 that, the manhole cover of the present disclosure has high strength to weight ratio.
The cover (100) can be made of any suitable composite material. The selection of material primarily depends upon the requirement of the chosen manufacturing process and the application requirement. In an embodiment, each of the first part (110), the second part (120), and the ribs (130) is made of a composite material with base material selected from the group consisting of polypropylene, polyethylene, nylon, polyethylene terephthalate, acrylonitrile butadiene styrene, and any combinations thereof. In an embodiment, fillers are added in the material of the cover (100) to strengthen the cover (100). Any suitable fillers, such as glass fibre, carbon fibre, similar fillers, or any combinations thereof, can be added in the composite material to increase the strength of the cover (100).
The cover (100) can be manufactured using any suitable manufacturing process. The ribs (130) are provided with a draft to ease the removal of a mould in case the cover (100) is manufactured using a moulding process. In an embodiment, each of the ribs (130) has a tapered configuration.
In another embodiment, the cover (100) is manufactured by injection moulding process. In injection moulding process, high degree of dimensional accuracy of the cover (100) can be achieved. In an embodiment, the cover (100) is manufactured using a mould having a core, a cavity, and a side core. To facilitate formation of spaces between adjacent ribs (130), the side core is used. Liquid material of the cover (100) is injected into the mould. Once the material gets solidified, the side core is pulled away from rib feature allowing the cover (100) to be released from mould. It is to be noted that the aforementioned method of manufacturing the cover (100) is for example purposes, and the cover (100) can be manufactured using any other suitable method and configuration of the mould.
Referring to Figure 1 to Figure 4, one embodiment of the cover (100) is shown. Referring to Figure 1 to Figure 4, the cover (100) has a circular shape, and a smooth top surface.
Referring to Figure 5 and Figure 6, another embodiment of the cover (100) is shown. In this embodiment, the cover (100) includes a mounting arrangement (145) configured to hingedly connect the cover (100) to a frame (150) (as shown in Figure 9). The frame (150) is placed on a manhole on which the cover (100) is to be provided. The frame (150) has a receiving arrangement (160) complementary to the mounting arrangement (145) for facilitating connection between the frame (150) and the cover (100). In an embodiment, the receiving arrangement (160) includes a protruded block configured to be received in a space defined by two blocks of the mounting arrangement (145). The protruded block and the blocks of the mounting arrangement comprise holes registering with each other in an operative configuration. Further, a bolt is passed through the holes so as to facilitate angular movement of the cover (100) with respect to the frame (105).
Although the mounting arrangement (145) is illustrated with reference to the cover (100) shown in Figure 5 and Figure 6, similar mounting arrangement (145) can be employed to the cover shown in Figure 1 to Figure 4, and Figures 7 and 8.
In an embodiment, an operative top surface of the cover (100) has a plurality of bumps (155) (as shown in Figure 5) configured thereon to increase friction between a pedestrian or vehicle passing over the cover (100) and to prevent slippage of the pedestrian or the vehicle.
The manhole cover (100) described hereinabove has high strength to weight ratio, easy to manufactures, and requires less time even for mass production. Further, the cover is light in weight which makes the installation, removal, and transportation of the cover easy. The cover has better aesthetics as compared to conventional manhole covers.
The manhole cover (100) described hereinabove can be used to cover any manhole such as manholes for inspection chambers for sewerages or for underground electrical and telecom cabling.
The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.