Variable sliding manhole safety guard

A variable sliding manhole safety guard to be installed at a manhole comprising:

• an installation support part (110) that is installed on an inner wall of the manhole (100) and has a rail structure vertically extending by a predetermined length and configured to change a vertical position of a movement guide (120);
• the movement guide (120) that is mounted on the rail structure to change a vertical position, and is integrally connected to a safety fence (130) to form an integrated structure therewith;
• the safety fence (130) which is integrally connected to the movement guide (120) to form an integrated structure and includes a plurality of frames forming a cylindrical structure having an outer diameter corresponding to an inner diameter of the manhole entrance, and in which an entrance door (160) configured to be opened and closed is installed on a side thereof;
• a safety fence position fixing part (140) which comprises a stopping lever (141) which is mounted over the safety fence (130) and performs a rotational operation, and a stopping member (142) configured to fix a vertical height of the movement guide (120) by the rotational operation of the stopping lever (141) and mounted at a lower part of the safety fence position fixing part (140);
• and
• a ladder (150) that is adjacent to the installation support part (110) and is installed in the manhole, and vertically extends by a predetermined length,
• wherein the installation support part (110) includes:
• a side wall installation plate (111) that has a curved structure corresponding to the inner wall of the manhole and extends into to the manhole from the manhole entrance by a predetermined length;
• an upper end fixing plate (112) that protrudes laterally from an upper end of the side wall installation plate (111) by a predetermined length and is bound to an upper end of a rail pipe;
• a lower portion fixing plate (113) that protrudes laterally from a lower end of the side wall installation plate (111) by a predetermined length and is bound to an outer circumferential surface of a lower portion of the rail pipe;
• a rail formation portion (114) that comprises the rail structure and is mounted by the upper end fixing plate (112) and the lower portion fixing plate (113) and has a hollow pipe structure extending from the manhole entrance to the inside of the manhole by a predetermined length;
• and
• an entrance foot plate (118) that protrudes laterally by a predetermined width, and is arranged spaced apart from a mounted position of the ladder (150) by a predetermined angle, and adjacent to the entrance door (160) in a plan view, and
• the movement guide (120) includes:
• a vertical extension portion (121) that has a pipe structure having the same outer diameter as an inner circumferential surface of the rail formation portion (114) and vertically extending by a predetermined length, and is bound to an upper end of the safety fence (130) at an upper end thereof in an integrated structure;
• an upper end guide plate (122) that is mounted at an upper end of the vertical extension portion (121), and has a plate-shaped structure bound to the upper end of the safety fence (130) in an integrated structure, and rotatably fixes an upper end of the safety fence position fixing part (140);
• and
• a lower end guide plate (123) that is mounted at a lower end of the vertical extension portion (121), and has a plate-shaped structure bound to a lower end of the safety fence (130) in an integrated structure, and rotatably fixes a lower end of the safety fence position fixing part (140);
• wherein the installation support part (110) further includes:
• a fixed pulley (115) that is mounted on a lower surface of the lower portion fixing plate (113) and supports vertical driving of a balance wire (116);
• the balance wire (116) that is mounted at a lower end of the movement guide (120), extends upward, passes through the fixed pulley (115), and extends downward, and is made of a material having a predetermined strength;
• and
• a weight (117) that is mounted at one end of the balance wire (116) and has the same weight as a sum of weights of the movement guide (120) and the safety fence (130);
• and
• wherein the safety fence (130) includes:
• an upper end ring frame (131) that is bound to an upper end of the movement guide (120) in an integrated structure and has a ring structure corresponding to the inner diameter of the manhole entrance;
• a lower end ring frame (132) that is bound to a lower end of the movement guide (120) in an integrated structure and has a ring structure corresponding to the inner diameter of the manhole entrance;
• and
• a vertical frame (133) that connects the upper end ring frame (131) and the lower end ring frame (132) in an integrated structure;
• wherein the entrance foot plate (118) is adjacent to the upper end guide plate (122) along the upper ring end frame (131), and
• wherein the upper ring frame (131) and the lower ring frame (132) are each a symmetric circular shape.