IES64901B2 - Improvements relating to gully tops and manhole tops - Google Patents

Abstract

A grating and frame assembly (1) for forming a gully top for vehicular and pedestrian areas has a frame (2) and a grating (3) hingedly mounted on the frame (2). Locking means for the grating (3) comprises a locking bolt (29) mounted on the grating (3) which is engageable with a complementary locknut (33) mounted in the frame (2). The locknut(33) is held captive within an associated housing (32) integrally cast with the frame (2) the housing (32) having a socket (35) for reception of the locknut (33). A welded ridge (42) at an inlet of the socket (35) retains the locknut (33) within the socket.

Description

Improvements relating to cnillv tops and manhole tops The invention relates to gully tops and manhole tops for vehicular and pedestrian areas as defined in European Standard EN124:1994 version and particularly made from those materials specified in that standard.

For clarity and consistency, this patent specification will refer to gratings and frames but this is understood to include covers and frames.

The invention particularly relates to a method for manufacturing a grating and frame for underground conduits. The grating and frame is of the type generally comprising a frame and a movable grating. It is known to provide a threaded fastener for releasably locking the grating in the frame in order to prevent unauthorised opening of the grating. For example, an opening may be provided in a grating for reception of a bolt which engages with a complementary threaded receiver cut or fixed in the frame.

However, a difficulty can arise in that unless the grating and frame are very accurately manufactured it can, in some cases, be difficult to align and engage the bolt with the associated threaded receiver in the frame. Further, if the threaded receiver is even slightly out of alignment, the bolt head will not seat properly with the grating. Also, if the bolt and receiver are of different materials, this will promote corrosion particularly as these gratings and frames are generally located in open exposed positions.

The invention is directed towards overcoming these problems and to provide an economic manufacturing solution. 364901 According to the invention, there is provided a grating and frame assembly comprising a frame defining an access opening, a complementary grating mounted in the frame to close the access opening, the grating movable between a closed position and an open position, locking means for releasably locking the grating on the frame, the locking means comprising a locking bolt mounted in the grating and a complementary lock nut mounted in the frame, the bolt mounted on an associated mounting flange integral with the grating and having a through hole for reception of the bolt, the lock nut held captive within an associated housing integrally cast with the frame, the housing having a slot for through passage of the bolt into the housing to engage the lock nut, the housing having a socket for reception of the lock nut, the socket of greater size than the lock nut for articulation of the lock nut within the socket while constraining the lock nut against rotation within the socket, and retaining means for blocking an inlet of the socket to retain the lock nut within the socket, the nut retaining means being a welded ridge at an inlet of the socket.

In one embodiment of the invention, the housing has a central slot or groove extending through a bottom of the housing.

In another embodiment, a retaining nut is provided for the locking bolt to secure the locking bolt on the mounting flange, the retaining nut being mounted intermediate the ends of the shank of the locking bolt.

In a preferred embodiment, the frame has a body having upstanding side walls defining an opening therebetween, outwardly projecting webs on an outer face of one or more of the side walls, a bedding flange being mounted between outer ends of the webs, the grating having a fixed inner end pivotally mounted by a spindle within the opening defined by the side walls, the mounting flange for the bolt being mounted at a free end of the grating.

The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only, with reference to the accompanying drawings, in which:Fig. 1 is a perspective view of a grating and frame assembly according to the invention; Fig. 2 is a detail perspective cut-away view showing locking means of the assembly; Fig. 3 is a detail sectional view of portion of the assembly showing the locking means; Fig. 4 is a detail end view of portion of the frame locking means; and Fig. 5 is a view similar to Fig. 3 showing the grating in a partially opened position.

Referring to the drawings, there is illustrated a grating and frame assembly according to the invention, indicated generally by the reference numeral 1. The assembly 1 comprises a frame 2 with a complementary grating 3 hingedly mounted on the frame 2 by a spindle 4 for movement between an open position and a closed position as illustrated in the drawings. A locking means indicated generally by the reference numeral 5, is provided for releasably locking the grating 3 on the frame 2.

The frame 2 comprises a body 6 formed by an upstanding front wall 7, rear wall 8 and end walls 9, 10 which define a rectangular opening 11. Projecting outwardly from the front wall 7 and each end wall 9, 10 are a number of spaced-apart upright webs 14, each having an upper sloped edge 15. A frame bedding flange 16 is supported at an outer end of each of the webs 14.

The grating 3 has a C-shaped pivot bar 20 at one end. Outwardly extending lugs 21 at each end of the pivot bar 20 have through holes 22 for rotatably engaging the spindle 4. Grating bars 24 extend outwardly of the pivot bar 20.

At a free end 26 of the grating 3, a locking flange 27 is mounted at an intersection of transverse and longitudinal grating bars 24. A through hole 28 is provided in the flange 27 for reception of a locking bolt 29. The locking bolt 29 is held captive on the flange 27 by a retaining nut 30 below the flange 27 on the shank of the bolt 29 or by other means.

Associated with the locking flange 27 is a housing 32 which is integrally cast with the frame 2 and located on an end wall 9. The housing 32 is for reception of a lock nut 33 associated with the locking bolt 29. The housing 32 has a socket 35 for reception of the lock nut 33, the socket 35 being larger than the lock nut 33 which is a loose fit in the socket 35 but restrained against turning in the socket 35 by the side walls of the socket 35. A top wall 38 of the housing 32 has a through hole 39 for through passage of the bolt 29 to engage the lock nut 33. A bottom wall 40 of the housing has a central slot 41. To retain the lock nut 33 within the socket 35, a welded projection 42 (Fig. 3) is provided at an inlet 43 of the socket 35.

In use, the grating 3 is normally closed on the frame 2, the bolt 29 engaging the nut 33 to releasably retain the grating 3 on the frame 2. For access, the nut 29 can be undone and the grating 3 lifted, the retaining nut 30 securing the bolt 29 in the grating 3. Also, the nut 33 is retained within the socket 35 of the housing 32 by the projection 42. When the grating 3 is closed, the bolt 29 can be readily easily aligned with the nut 33 as the nut 33 is free to articulate within the socket 35 to facilitate easy alignment of the bolt 29 with the nut 33.

It will be noted that the grating 3 and the frame 2 are preferably manufactured from graphite cast iron. The bolt 29 and nut 33 are of similar material, preferably ferrous material but, in some cases, they may be of some other material.

The fact that the nut 33 is loosely located within the socket 35 facilitates alignment of the bolt 29 with the nut 33. It will also be appreciated that the bolt 29 and nut 33 can be readily easily replaced if necessary.

The invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail.

Claims (5)

CLAIMS.

1. A grating and frame assembly comprising a frame defining an access opening, a complementary grating < mounted in the frame to close the access opening, the grating movable between a closed position and an open position, locking means for releasably locking the grating on the frame, the locking means comprising a locking bolt mounted in the grating and a complementary lock nut mounted in the frame, the bolt mounted on an associated mounting flange integral with the grating and having a through hole for reception of the bolt, the lock nut held captive within an associated housing integrally cast with the frame, the housing having a slot for through passage of the bolt into the housing to engage the lock nut, the housing having a socket for reception of the lock nut, the socket of greater size than the lock nut for articulation of the lock nut within the socket while constraining the lock nut against rotation within the socket, and retaining means for blocking an inlet of the socket to retain the lock nut within the socket, the nut retaining means being a welded ridge at an inlet of the socket.

2. An assembly as claimed in claim 1 wherein the housing has a central slot or groove extending through a bottom of the housing.

3. An assembly as claimed in any preceding claim wherein a retaining nut is provided for the locking bolt to * secure the locking bolt on the mounting flange, the retaining nut being mounted intermediate the ends of < the shank of the locking bolt.

4. An assembly as claimed in any preceding claim wherein the frame has a body having upstanding side walls defining an opening therebetween, outwardly projecting webs on an outer face of one or more of 5 the side walls, a bedding flange being mounted between outer ends of the webs, the grating having a fixed inner end pivotally mounted by a spindle within the opening defined by the side walls, the mounting flange for the bolt being mounted at a free end of 10 the grating.

5. A grating and frame assembly substantially as hereinbefore described with reference to the accompanying drawings.