WO2008062960A1

WO2008062960A1 - An assembly manhole having s-shaped hinge structure

Info

Publication number: WO2008062960A1
Application number: PCT/KR2007/005654
Authority: WO
Inventors: Yoon Ho Choi
Original assignee: Choi Youn Ho
Priority date: 2006-11-21
Filing date: 2007-11-09
Publication date: 2008-05-29

Abstract

The present invention aims to provide a manhole assembly having an S-shaped hinge structure such that a manhole cover (10) is coupled to a manhole cover frame (20) so as to be rotatable and is prevented from being undesirably separated or removed from the manhole cover frame by backflowing rainwater or an impact transmitted from a vehicle. The manhole cover is opened to a degree corresponding to the amount of backflowing rainwater and is automatically closed by its own weight. Furthermore, an odor prevention door (17) is provided on an open end of a drainage channel defined in the manhole cover, thus preventing the dispersion of odors. In addition, a water drain slot (28) is formed in the manhole cover frame, which contacts a road surface, so that water that gathers on a road surface can be drained through the water drain slot, thus preventing the road from subsiding.

Description

AN ASSEMBLY MANHOLE HAVING S-SHAPED HINGE

STRUCTURE

Technical Field

[1] The present invention relates, in general, to manhole assemblies having S-shaped hinge structures and, more particularly, to a manhole assembly in which a manhole cover, which has a drainage channel therein and is provided with an odor prevention door, is coupled to a manhole cover frame so as to be rotatable using an S-shaped hinge structure. Background Art

[2] In the present invention, when rainwater and sewage flow backwards from a manhole, a manhole cover is opened to a degree corresponding to the amount of backflowing rainwater and sewage, and, when backflowing rainwater and sewage no longer flow, the manhole cover is closed by its own weight, that is, returned to its original position. This can be achieved using an S-shaped hinge coupling structure, by which the manhole cover is coupled to a manhole cover frame.

[3] Under normal conditions, sewage odors are prevented from being transmitted outside the manhole. However, when a flood occurs, the manhole cover is variably opened to a degree corresponding to the amount of backflowing rainwater. The present invention provides a hinge coupling structure such that the manhole cover is prevented from being undesirably removed or separated from the manhole cover frame by the backflow of rainwater or impacts applied from vehicles.

[4] Furthermore, it is easy to assemble or disassemble the manhole cover to or from the manhole cover frame, and it is easy to clean the manhole assembly.

[5] In the case of a conventional manhole cover, it has a basic structure in which drain holes are formed through the cover body and, therefore, is problematic in that odors cannot be prevented from being transmitted outside the manhole. Meanwhile, when a flood occurs or a heavy rainy is visited, for example, in the rainy season, if the amount of rainwater exceeds the capacity of a drainpipe, rainwater flows backwards.

[6] The pressure of such backflowing rainwater may separate or remove the manhole cover from the manhole cover frame.

[7] The case where the manhole cover is in an incorrect position is very dangerous for vehicles and pedestrians.

[8] Furthermore, the conventional manhole cover is configured such that it is independently placed on the manhole cover frame without using a separate coupling means. [9] The conventional manhole cover is merely fastened with a latch to prevent the manhole cover from being removed from the manhole cover frame by an impact applied from a vehicle. In addition, the conventional manhole cover has a structure such that it cannot rotate with respect to the manhole cover frame.

[10] Meanwhile, in the conventional art, it is difficult to rotate the manhole cover with respect to the manhole cover frame using a typical hinge in a state in which the manhole cover is inserted in the manhole cover frame, because there is insufficient clearance space to rotate the manhole cover around the hinge shaft.

[11] As the height of the manhole cover frame is increased, it becomes still more difficult to rotate the manhole cover, because the height of the manhole cover interferes with the rotation of the manhole cover.

[12] If the manhole cover is rotatably coupled to the manhole cover frame, the manhole cover will be prevented from being undesirably separated or removed from the manhole cover frame by backflowing water or an impact transmitted from a vehicle.

[13] Therefore, the present invention focuses on the hinge coupling structure.

Disclosure of Invention Technical Problem

[14] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a manhole assembly having an S-shaped hinge structure such that a manhole cover is coupled to a manhole cover frame so as to be smoothly rotatable and is prevented from being undesirably separated or removed from the manhole cover frame by backflowing rainwater or an impact transmitted from a vehicle, and such that the manhole cover is opened to a degree corresponding to the amount of backflowing rainwater and is automatically closed by its own weight.

[15] Another object of the present invention is to provide a manhole assembly in which a water drain slot is formed through a rear rim part of the manhole cover frame which contacts a road surface to drain water, which is gathered on a road surface, therethrough, thus preventing the road surface from subsiding.

[16] A further object of the present invention is to provide a manhole assembly in which the thickness of each of opposite sidewall parts and a rear surface part of the manhole cover is equal to the width of each of opposite side rim parts and the rear rim part of the manhole cover frame, such that the manhole cover can be reliably supported on the rim parts of the manhole cover frame, and lightness of the manhole assembly is accomplished.

[17] Yet another object of the present invention is to provide a manhole assembly in which an odor prevention door is provided on an open front end of a drainage channel of the manhole cover, thus preventing the dispersion of odors. Technical Solution

[18] In order to accomplish the above objects, the present invention provides a manhole assembly in which a manhole cover is coupled to a manhole cover frame using an S- shaped hinge structure so as to be movable along an s-shaped path.

Advantageous Effects

[19] In the manhole assembly according to the present invention, because a manhole cover is coupled to a manhole cover frame using an S-shaped hinge structure so as to be movable along an s-shaped path, the manhole cover is prevented from being undesirably separated or removed from the manhole cover frame by backflowing rainwater or an impact transmitted from a vehicle.

[20] Furthermore, the present invention has a hinge structure such that, when rainwater or sewage flows backwards, the manhole cover is opened to a degree corresponding to the amount of backflowing rainwater or sewage, and, when backflowing rainwater or sewage is removed, the manhole cover is automatically closed by its own weight. Thanks to this simple structure, it is easy to assemble or disassemble the manhole assembly.

[21] In addition, in the present invention, a removal prevention protrusion is provided in the S-shaped hinge slot at a position that is slightly spaced apart from the lowermost point P in a leftward direction. Thus, a hinge protrusion is prevented from being undesirably removed from the removal prevention protrusion, by which the manhole cover is prevented from being undesirably removed.

[22] As well, the thickness of each of opposite sidewall parts and the rear surface part of the manhole cover is equal to the width of each of opposite side rim parts and the rear rim part of the manhole cover frame. Therefore, the manhole cover can be reliably supported on the rim parts of the manhole cover frame, and, because the lightness of the manhole assembly is accomplished, it is easy to handle the manhole assembly.

[23] Moreover, a drainage channel is defined in the manhole cover, and an odor prevention door is provided on the open end of the drainage channel, thus preventing the dispersion of odors.

[24] Furthermore, a water drain slot is formed through the rear rim part of the manhole cover frame, which contacts the road surface, so that water, which is gathered on the road surface, can be drained through the water drain slot. Therefore, there is an advantage in that the road surface is prevented from subsiding due to freezing and melting of water. Brief Description of the Drawings

[25] FIG. 1 is an assembled view of a manhole assembly, including a manhole cover and a manhole cover frame, according to the present invention;

[26] FIG. 2 is a bottom perspective view of FIG. 1 ;

[27] FIG. 3 is an exploded perspective view of the manhole assembly according to the pr esent invention;

[28] FIG. 4 is a bottom perspective view of the manhole cover according to the present invention;

[29] FIG. 5 is a sectional view taken along the line A-A' of FIG. 1;

[30] FIG. 6 is a sectional view taken along the line B-B' of FIG. 1;

[31] FIG. 7 illustrates the operation of opening the manhole cover using S-shaped hinge slots and hinge protrusions according to the present invention;

[32] FIG. 8 is an enlarged view of a circled portion A of FIG. 7; and

[33] FIG. 9 is an enlarged view of a circled portion B of FIG. 7.

Best Mode for Carrying Out the Invention

[34] Hereinafter, a preferred embodiment for achieving the purpose of the present invention will be described in detail with reference to the attached drawings.

[35] The manhole assembly 100 includes a manhole cover and a manhole cover frame.

[36] 1) Structure of the manhole cover 10

[37] The manhole cover 10 has a drainage channel defined therein.

[38] The drainage channel is defined by an upper surface part 13, which has drain holes

12 therein, a bottom surface part 14 of the manhole cover, sidewall parts 15 of the manhole cover and a rear surface part 16 of the manhole cover. The bottom surface part 14, the sidewall parts 15 and the rear surface part 16 of the drainage channel are closed, but the front end of the drainage channel is open. Furthermore, an openable odor prevention door 17, which is coupled to the upper surface part 13, having the drain holes 12, by a hinge, is provided on the open front end of the drainage channel.

[39] The sidewall parts 15 and the rear surface part 16 of the drainage channel are the same height h, and the manhole cover frame 20, corresponding thereto, has the same height h as the sidewall parts and the rear surface part. The bottom surface part 14 of the drainage channel is inclined downwards in the direction in which the drainage channel is open.

[40] As such, because the bottom surface part 14 is inclined downwards from the rear surface part 16 to the open front end of the drainage channel, the height of the drainage channel is increased from the rear surface part 16 to the open front end of the drainage channel.

[41] The manhole cover is constructed such that, because the sidewall parts 15 and the rear surface part 16 of the drainage channel are seated onto opposite side rim parts 26 and a rear rim part 27 of the manhole cover frame 20, the sidewall parts 15 and the rear surface part 16 of the drainage channel protrude downwards from the bottom surface part 14 of the drainage channel. Furthermore, because the bottom surface part 14 of the drainage channel is inclined downwards towards the open front end of the drainage channel, the height to which each sidewall part protrudes from the bottom surface part is increased towards the rear surface part 16 of the drainage channel and is reduced towards the open front end thereof.

[42] The length of the upper surface part 13 of the manhole cover 10 is greater than the bottom surface part 14 of the drainage channel. The odor prevention door is hinged to the upper surface part 13 of the manhole cover 10 and is oriented so as to be inclined at a predetermined angle such that it can be opened by rainwater which is drawn into the drainage channel. Furthermore, when rainwater is removed, the odor prevention door 17, which has been opened by rainwater, is automatically closed by its own weight, which is applied in the direction of gravity.

[43] As such, the odor prevention door 17 is provided so that it is inclined at a predetermined angle. Therefore, when no rainwater is drawn into the manhole assembly, the odor prevention door remains in a closed state, thus preventing the dispersion of odors.

[44] Meanwhile, when it rains, rainwater is drawn into the drainage channel through the drain holes 12 and, thereafter, flows through the manhole via the odor prevention door 17. The present invention has the structure such that rainwater that is drawn into the manhole assembly through the drain holes 12 can open the odor prevention door 17 and flow into the manhole, but water that flows backwards from the manhole cannot open the odor prevention door 17.

[45] However, when a large amount of rainwater flows backwards from the manhole, for example, when a flood occurs, the entire manhole cover 10 is lifted upwards and is opened without opening the odor prevention door 17. In the case of the conventional manhole cover, there is a problem in that the manhole cover, which is opened by backflowing rainwater, is displaced from its correct position or is damaged by the force of backflowing rainwater.

[46] The case where the manhole cover 10 is in an incorrect position is very dangerous for people riding in vehicles. It also is very dangerous for pedestrians. Furthermore, in conditions in which the manhole cover cannot be observed, the possibility of a safety hazard is further increased.

[47] 2) Structure of the manhole cover frame 20

[48] The manhole cover frame 20 includes four frame parts, that is, opposite sidewall frame parts 24, a front frame part 22 and a rear frame part 23. The opposite side rim parts 24 and the rear rim part 23 are provided on respective lower edges of the inner surfaces of the sidewall frame parts 24 and the rear frame part 23. The manhole cover frame has no front rim part. A stepped part 221 is formed in the upper edge of the inner surface of the front frame part 22 in the longitudinal direction of the front frame part 22. The upper surface part 13 having the drain holes 12 is seated onto the stepped part 221.

[49] 3) Relationship between the manhole cover 10 and the manhole cover frame 20

[50] The relationship between the manhole cover 10 and the manhole cover frame 20 will be explained herein below.

[51] The upper surface of the manhole cover 10 and the upper end of the manhole cover frame 20 are level with each other, thus forming a single horizontal plane.

[52] In a state in which the manhole cover 10 is closed, the protruding lower ends of the sidewall parts 15 of the drainage channel and the protruding lower end of the rear surface part 16 of the drainage channel are seated on the opposite side rim parts 26 and the rear rim part 27 of the manhole cover frame 20. Because the bottom surface part 14 of the drainage channel is inclined downwards from the rear surface part 16 to the open front end, the lower ends of the sidewall parts 15 and the lower end of the rear surface part 16 of the drainage channel slightly protrude downwards from the bottom surface part.

[53] Meanwhile, an S-shaped hinge structure includes hinge protrusions 40, which are provided at predetermined positions on the respective opposite sidewall frame parts 26 of the manhole cover frame 20, and S-shaped slots 30, which are formed in the respective opposite sidewall parts 15 of the manhole cover 10 to correspond to respective hinge protrusions.

[54] 4) S-shaped hinge structure

[55] The operation of opening or closing the manhole cover 10 using the S-shaped hinge structure will be explained herein below.

[56] The hinge protrusions 40, which are provided on the manhole cover frame 20, are maintained at fixed positions, while the S-shaped hinge slots 30, which are formed in the manhole cover 10, are movable. The opening or closing of the manhole cover 10 is determined by the movement of the hinge slots 30.

[57] The degree, to which the manhole cover is opened depending on the movement of the S-shaped hinge slots 30 is shown in FIG. 7, illustrating the operation of the manhole cover.

[58] This will be explained herein below with reference to the operation view of FIG. 7 and the enlarged sectional views of FIGS. 8 and 9.

[59] As shown in a view of the manhole cover opening ®, the lowermost point of the S- shaped hinge slot S is designated by the character P, the point at which the hinge protrusion 40 is disposed is designated by the character O, and the top point and the bottom point of the manhole cover are respectively designated by the characters B and B.

[60] In the S-shaped hinge slot 30, an arc section PO pertains to the operation of opening or closing the manhole cover 10.

[61] In detail, in the state in which the manhole cover 10 is closed, the hinge protrusion

40 is disposed at the top point O in the S-shaped hinge slot 30 (refer to the view of the manhole cover opening-®).

[62] In contrast, in the state in which the manhole cover 10 is completely opened, the hinge protrusion 40 is disposed at the point P in the S-shaped hinge slot 30 (refer to the view of the manhole cover opening-©).

[63] Hereinafter, the operation of opening the manhole cover 10, which has been in the closed state (see, the view of the manhole cover opening-®) will be explained with reference to the relationship between the S-shaped hinge slot 30 and the hinge protrusion 40.

[64] The top point Q and the bottom point A of the manhole cover 10 are in contact with the corresponding frame parts of the manhole cover frame 20 (refer to the view of the manhole cover opening-®).

[65] To rotate the manhole cover 10, a radius OQ and a radius OA must be able to rotate around the point O of the hinge protrusion 40 at the same time. In other words, to allow the manhole cover to rotate, the radius OQ must have clearance space in a horizontal direction, and, simultaneously, the radius OA must have clearance space in a vertical direction.

[66] Here, because the point O of the hinge protrusion 40, which is provided on the manhole cover frame 20, is maintained at a stationary position, when seen on the basis of the manhole cover frame 20, the radius OQ or OR of the manhole cover 10 always maintains a preset length, but, when seen on the basis of the manhole cover 10, the horizontal length and the vertical length of the radius OQ or OR of the manhole cover 10 are varied at the same time by an amount that depends on the position at which the hinge protrusion is disposed in the S-shaped hinge slot 30.

[67] As the radii OQ and OR of the manhole cover 10 are reduced, the clearance space between the manhole cover 10 and the corresponding frame parts of the manhole cover frame 20 is increased, so that the rotation of the manhole cover 10 can be smoothly conducted.

[68] That is, when seen on the basis of the S-shaped hinge slot 30, as the lowermost point P approaches the point O in the S-shaped hinge slot 30, the horizontal distance and the vertical distance are reduced at the same time, and clearance space is thereby increased. Thus, the smooth rotation of the manhole cover 10 is ensured.

[69] FIG. 7 is the operational views illustrating a change in the position of the hinge protrusion 40 with respect to the S-shaped hinge slots 30 during the entire process from the completely closed state of the manhole cover 10 to the completely open state thereof (with reference to the enlarged sectional views of FIGS. 8 and 9).

[70] In the state in which the manhole cover 10 is completely closed (refer to the view of the manhole cover opening-®), the hinge protrusion 40 is disposed at the top point O of the S-shaped hinge slot 30.

[71] In contrast, in the state in which the manhole cover 10 is completely opened (refer to the view of the manhole cover opening-©), the hinge protrusion 40 is disposed at the lowermost point P in the S-shaped hinge slot 30.

[72] As such, depending on the degree to which the manhole cover 10 is opened, the hinge protrusion 40 is moved between the top point O and the lowermost point P in the S-shaped hinge slot.

[73] This will be easily appreciated from the views illustrating the operation of opening the manhole cover from the manhole cover opening-® to the manhole cover opening- ©.

[74] As such, when the hinge protrusion 40 moves from the top point O to the lowermost point P in the S-shaped hinge slot, the top point B of the manhole cover 10 can be smoothly moved towards the bottom point A without restriction.

[75] Meanwhile, in consideration of the fact that the operation of opening or closing the manhole cover 10 pertains only to the section PO of the S-shaped hinge slot, a removal prevention protrusion 32 may be provided in the S-shaped hinge slot at a position that is slightly spaced apart from the lowermost point P in a leftward direction. In this case, the removal prevention protrusion 32 prevents the hinge protrusion 40 from being undesirably removed from the S-shaped hinge slot, thus preventing the manhole cover 10 from being separated from the manhole cover frame by water, which flows backwards, or by an impact transmitted from a vehicle. This can be realized by the configuration such that the width of the hinge slot 30 is reduced by the removal prevention protrusion 32 and is thus less than the diameter of the hinge protrusion 40.

[76] Here, preferably, the reduced width of the hinge slot 30, attributable to the removal prevention protrusion 32, is sufficient to insert or remove the hinge protrusion into or from the hinge slot when appropriate force is applied to the manhole cover 10 to assemble or disassemble the manhole assembly. This is realized by the elasticity of polymer engineering plastic, which is the material of the manhole assembly 100.

[77] Meanwhile, a plurality of water drain slots 28 is formed through the rear rim part 27 and a flange of the manhole cover frame 20, which contact the road surface. The water drain slots 28 serve to drain water, which gathers on the road surface, therethrough, and to prevent the road from subsiding due to freezing in the winter.

[78] A process of assembling the manhole cover 10 with the manhole cover frame 20 will be explained herein below. [79] The manhole cover frame 20 is securely fixed to a desired place in which the manhole assembly is constructed.

[80] Thereafter, the manhole cover 10 is coupled to the manhole cover frame 20 such that the hinge protrusions 40 of the manhole cover frame 20 are inserted into the respective S-shaped hinge slots 30 of the manhole cover 10. At this time, if the hinge protrusions 40 of the manhole cover frame 20 are merely inserted into respective S- shaped hinge slots 30 of the manhole cover 10 without applying additional force to the manhole cover, the manhole cover 10 is in a state in which the hinge protrusions 40 are stopped by the corresponding removal prevention protrusions 32, that is, in a state just before the hinge protrusions 40 reaches the lowermost point P.

[81] The reason for this construction is that the removal prevention protrusions 32 are disposed at positions right before the lowermost points P in the respective S-shaped hinge slots. The hinge protrusions 40 must pass through the removal prevention protrusions 32 to reach the respective lowermost points P. Furthermore, only when the hinge protrusions 40 are at the respective lowermost points P can the manhole cover 10 rotate to thus open or close the manhole assembly, because the operation of opening or closing the manhole cover 10 can be conducted when the hinge protrusions are in the sections PO of the respective S-shaped hinge slots.

[82] To position the hinge protrusions 40, which are stopped by the removal prevention protrusions 32, at the respective lowermost points P, a predetermined amount of force must be applied to the manhole cover 10. In contrast, to disassemble the manhole assembly, the manhole cover must be pulled with a predetermined amount of force. Mode for the Invention

[83] Preferably, because the manhole cover 10 is rotated using the S-shaped hinge slots

30 and the hinge protrusions 40, corresponding corners of the manhole cover 10, which interfere with the manhole cover frame 20, are rounded at appropriate curvatures. Thanks to this configuration, the manhole cover 10 can be smoothly rotated without interference from the manhole cover frame 20.

[84] For example, front ends E and rear ends F of the opposite sidewall parts of the manhole cover 10 may be rounded at appropriate curvatures. In particular, each front end E is formed so as to be inclined rearwards and rounded at an appropriate curvature, and each rear end F is simply rounded.

[85] Furthermore, in the present invention, the drainage channel is defined in the manhole cover 10, and the openable odor prevention door 17 is provided on the open front end of the drainage channel so as to be inclined at a predetermined angle.

[86] Because the odor prevention door 17, which is provided on the opening of the drainage channel, which is defined both by the front end of the bottom surface part 14 of the drainage channel and by the front end of the upper surface part 13 of the manhole cover, which is shorter than the bottom surface part 14, the odor prevention door 17 is oriented so as to be inclined at a predetermined angle. Furthermore, the odor prevention door 17 maintains a closed state under normal conditions.

[87] The bottom surface part 14 of the drainage channel is inclined downwards to ensure the smooth flow of water.

[88] Because the sidewall parts 15 and the rear surface part 16 of the manhole cover 10 are the same height, and because the bottom surface part 14 of the drainage channel is inclined downwards, a space is defined under the bottom surface part 14 by the lower surface of the bottom surface part 14 of the drainage channel and by the lower ends of the sidewall parts 15 and the rear surface part 16, which protrude downwards from the bottom surface part 14. As such, because the space is defined under the lower surface of the bottom surface part 14, reinforcing protrusions 142 can be easily formed. The reinforcing protrusions 142 serve to reinforce the strength of the bottom surface part 14.

[89] In addition, the water drain slots 27 are formed through the rear rim part 27 and the flange of the manhole cover frame 20. The water drain slots serve to drain water, which gathers on the road surface, therethrough and to prevent subsidence of the road due to freezing in the winter.

[90] The manhole cover 10 and the manhole cover frame 20 are made of polymer engineering plastic, which is environment-friendly. This material is stronger than cast iron, and the impact resistance, corrosion resistance and abrasion resistance thereof are superior thereto. Thus, the manhole assembly of the present invention is semipermanent. In addition, because the present invention can have various colors, it can be designed to have a color suitable for the surroundings. As well, the present invention is relatively light, so that it easy to carry and work with.

[91] Moreover, because the coupling structure between the S-shaped hinge slots 30 and the hinge protrusions 40 is simple, the present invention is easily adapted for mass production, thus enhancing productivity. Furthermore, the manhole assembly of the present invention does not require any separate post-process and, therefore, can be rapidly manufactured, thus being very economical.

[92] In the present invention, because the hinge structure is simple, it is easy to assemble or disassemble the manhole cover 10 with the manhole cover frame, thus making it easy to clean the manhole assembly, and making it unnecessary to clean the bottom of a drain.

[93] Furthermore, when rainwater and sewage flow backwards from the manhole, the manhole cover 10 is opened to a degree corresponding to the amount of backflowing rainwater and sewage, and, when conditions are normal, the manhole cover 10 is closed, that is, returned to its original position, thus maintaining a stable structure.

Claims

[1] A manhole assembly having an S-shaped hinge structure, the manhole assembly

(100) including a manhole cover (10) and a manhole cover frame (20), wherein the manhole cover (10) has therein a drainage channel, a structure of which is defined by a bottom surface part (14) of the drainage channel and by opposite sidewall parts and a rear surface part of the drainage channel, which have a same height (h), the bottom surface part (14) of the drainage channel having a length shorter than a length of an upper surface part 13, which has a plurality of drain holes (12) therein, each of the opposite sidewall parts (15) of the drainage channel having an S-shaped hinge slot (30) therein, and the manhole cover frame (20), corresponding to the manhole cover, comprises four frame parts, including opposite sidewall frame parts (24), a front frame part (22) and a rear frame part (23), the four frame parts having heights (h) equal to the heights (h) of the opposite sidewall parts (15) and the rear surface part (16) of the drainage channel, with opposite side rim parts (26) and a rear rim part (2) extending inwards from respective lower ends of the opposite sidewall frame parts (24) and the rear frame part (23), each of the opposite side rim parts (26) and the rear rim part (2) having a width (b) equal to a thickness (t) of each of the opposite sidewall parts (15) and the rear surface part (16) of the drainage channel, and a hinge protrusion (40) provided on each of the opposite sidewall frame parts (24) at a position corresponding to the corresponding hinge slot (30), wherein the hinge protrusion (40) moves between a top point (O) and a lowermost point (P) of the corresponding S-shaped hinge slot (30), so that the manhole cover (10) is opened or closed using movement of the hinge protrusions (40) along a moving path (OP).

[2] The manhole assembly having the S-shaped hinge structure according to claim 1, wherein a water drain slot (28) is formed through the rear rim part (27) of the manhole cover frame (20), which contacts a road surface, and a stepped part (221) is formed in an upper edge of an inner surface of the front frame part (22) of the manhole cover frame (20) in a longitudinal direction of the front frame part.

[3] The manhole assembly having the S-shaped hinge structure according to claim 1 or 2, wherein a removal prevention protrusion (32) is provided in the S-shaped hinge slot (30) at a position slightly spaced apart from the lowermost point (P) in a leftward direction, and the manhole assembly (100) is made of polymer engineering plastic.