GB2122671A - Improvements relating to manhole covers - Google Patents

Abstract

A manhole cover comprises a peripheral rim (5) to which a cover (1) is hinged, piston and cylinder means (7, 9) being connected to the cover (1) to enable the cover (1) to be simply pivoted relative to the rim (5). Preferably the piston and cylinder means (7, 9) are of the double acting type and are remotely controlled. The piston and cylinder means (7, 9) can be hydraulically or pneumatically operable, and enable the cover (1) to be easily lifted and lowered as desired. <IMAGE>

Description

SPECIFICATION Improvements relating to manhole covers The present invention relates to a manhole cover of the type used to cover and, if necessary, seal openings to underground facilities such as drains.

Manhole covers are usually made of metal and can take any required shape e.g. rectangular, circular etc. They are usually located over a complementary rim secured around the opening in the ground. Such manhole covers are either completely separable from the complementary rim or are hinged thereto. However, in either case it is usually difficult to iift and lower manhole covers, especially when they are heavy metal structures.

Various types of manually usable tools are often provided to try to make the handling of manhole covers that bit easier. However such tools always require an amount of physical effort on the part of the person moving the manhole cover.

The aim of the present invention is to provide a manhole cover which is easy to open and close in comparison with previously known manhole designs.

According to the present invention there is provided a manhole cover comprising a peripheral rim to which a cover is hinged, piston and cylinder means being connected to the cover to enable the cover to be pivoted relative to the peripheral rim.

In a preferred embodiment of the present invention the piston and cylinder means are pneumatically operable, the cylinder being pivotally connected to the peripheral rim and the piston being connected via a piston rod to the cover. The piston and cylinder are preferably controlled from a remote location enabling the manhole cover to be either lifted or lowered by throwing a switch. In an alternative embodiment the piston and cylinder means are hydraulically operable.

The present invention thus enables a manhole cover to be simply and easily iifted and iowered as and when required, without physical effort or the use of suitable tools.

The present invention will now be further described, by way of example with reference to the accompanying drawing which shows a preferred embodiment of the present invention.

In the accompanying drawing, the manhole cover comprises a rectangular cover 1 which is hinged at 3 to a complementary peripheral rim 5.

Pivotally attached to the rim 5 is one end region of a cylinder 7 of a pneumatic piston and cylinder arrangement 7, 9, the piston (not visible) being connected to the cover 1 via a piston rod 9. The pneumatic piston and cylinder arrangement 7, 9 is of the double acting type and is controllable from a remote location 11 via, for example, an underground power connection 1 3. Alternatively a hydraulic piston and cylinder arrangement can be substituted for the pneumatic arrangement.

In use, the peripheral rim 5 is bolted to the ground e.g. concrete, surrounding the opening in the ground to be closed by the manhole. Then by manual operation of the remote control 11 i.e. by merely throwing a switch, the manhole cover 1 can be easily and quickly opened and closed.

Further by locking the remote control 11, the manhole cover 1 can be locked in the open or closed position. Further remotely controllable locking means (not shown) can additionally be provided to simplify the operation of securing the manhole cover to the peripheral rim, against unauthorised entry or access.

The present invention thus provides a simple form of readily operable manhole cover obviating the necessity for special tools and physical effort for opening and closing a manhole.

1. A manhole cover comprising a peripheral rim to which a cover is hinged, piston and cylinder means being connected to the cover to enable the cover to be pivoted relative to the peripheral rim.

2. A manhole cover as claimed in claim 1, in which the piston and cylinder are pneumatically operable.

3. A manhole cover as claimed in claim 1, in which the piston and cylinder are hydraulically operable.

4. A manhole cover as claimed in any one of claims 1 to 3, in which the cylinder is pivotally connected to the peripheral rim and the piston is connected via a piston rod to the cover.

5. A manhole cover as claimed in any one of claims 1 to 4, in which the piston and cylinder means are of the double-acting type.

6. A manhole cover as claimed in any one of the preceding claims, in which the piston and cylinder means are controllable from a remote location.

7. A manhole cover constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements relating to manhole covers The present invention relates to a manhole cover of the type used to cover and, if necessary, seal openings to underground facilities such as drains. Manhole covers are usually made of metal and can take any required shape e.g. rectangular, circular etc. They are usually located over a complementary rim secured around the opening in the ground. Such manhole covers are either completely separable from the complementary rim or are hinged thereto. However, in either case it is usually difficult to iift and lower manhole covers, especially when they are heavy metal structures. Various types of manually usable tools are often provided to try to make the handling of manhole covers that bit easier. However such tools always require an amount of physical effort on the part of the person moving the manhole cover. The aim of the present invention is to provide a manhole cover which is easy to open and close in comparison with previously known manhole designs. According to the present invention there is provided a manhole cover comprising a peripheral rim to which a cover is hinged, piston and cylinder means being connected to the cover to enable the cover to be pivoted relative to the peripheral rim. In a preferred embodiment of the present invention the piston and cylinder means are pneumatically operable, the cylinder being pivotally connected to the peripheral rim and the piston being connected via a piston rod to the cover. The piston and cylinder are preferably controlled from a remote location enabling the manhole cover to be either lifted or lowered by throwing a switch. In an alternative embodiment the piston and cylinder means are hydraulically operable. The present invention thus enables a manhole cover to be simply and easily iifted and iowered as and when required, without physical effort or the use of suitable tools. The present invention will now be further described, by way of example with reference to the accompanying drawing which shows a preferred embodiment of the present invention. In the accompanying drawing, the manhole cover comprises a rectangular cover 1 which is hinged at 3 to a complementary peripheral rim 5. Pivotally attached to the rim 5 is one end region of a cylinder 7 of a pneumatic piston and cylinder arrangement 7, 9, the piston (not visible) being connected to the cover 1 via a piston rod 9. The pneumatic piston and cylinder arrangement 7, 9 is of the double acting type and is controllable from a remote location 11 via, for example, an underground power connection 1 3. Alternatively a hydraulic piston and cylinder arrangement can be substituted for the pneumatic arrangement. In use, the peripheral rim 5 is bolted to the ground e.g. concrete, surrounding the opening in the ground to be closed by the manhole. Then by manual operation of the remote control 11 i.e. by merely throwing a switch, the manhole cover 1 can be easily and quickly opened and closed. Further by locking the remote control 11, the manhole cover 1 can be locked in the open or closed position. Further remotely controllable locking means (not shown) can additionally be provided to simplify the operation of securing the manhole cover to the peripheral rim, against unauthorised entry or access. The present invention thus provides a simple form of readily operable manhole cover obviating the necessity for special tools and physical effort for opening and closing a manhole. CLAIMS

1. A manhole cover comprising a peripheral rim to which a cover is hinged, piston and cylinder means being connected to the cover to enable the cover to be pivoted relative to the peripheral rim.

2. A manhole cover as claimed in claim 1, in which the piston and cylinder are pneumatically operable.

3. A manhole cover as claimed in claim 1, in which the piston and cylinder are hydraulically operable.

4. A manhole cover as claimed in any one of claims 1 to 3, in which the cylinder is pivotally connected to the peripheral rim and the piston is connected via a piston rod to the cover.

5. A manhole cover as claimed in any one of claims 1 to 4, in which the piston and cylinder means are of the double-acting type.

6. A manhole cover as claimed in any one of the preceding claims, in which the piston and cylinder means are controllable from a remote location.

7. A manhole cover constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.