GB2160170A

GB2160170A - Davit (especially for vehicles)

Info

Publication number: GB2160170A
Application number: GB08513284A
Authority: GB
Inventors: Kenneth Edward Forshaw
Original assignee: Didsbury Engineering Co Ltd
Current assignee: Didsbury Engineering Co Ltd
Priority date: 1984-06-15
Filing date: 1985-05-28
Publication date: 1985-12-18
Also published as: GB8513284D0

Abstract

A folding davit has a rotatable upright column 13 to the top of which is pivoted a manually length-adjustable jib arm 18 pivotal about a horizontal axis 19. There is a manually length-adjustable control strut 30 pivotally connected to both the upright column and the jib arm and this control strut is stowable within the column with the jib arm being releasably fastened to the column in substantially parallel relationship thereto when the davit is not in use. The column can be rotatably supported through the intermediary of bearing means 10 on a base plate 12 capable of being fastened to a vehicle bed. Alternatively, the column is provided with a bottom spigot 50 (Figure 4) rotatably housed in a socket 51 also secured to the vehicle bed. An electrically operated winch 60 (Figure 5) may be attached to the jib arm with pulleys 65, 67 at the ends of the jib arm. This winch 60 may be powered from the van battery. Alternatively a self-contained manually-(or power-) operated hoist 41 (Figure 3) may be connected to the free end of the jib arm 18. <IMAGE>

Description

SPECIFICATION Davit This invention relates to a davit, especially but not exclusively to a folding davit, on which can be mounted or suspended a lifting device or arrangement.

A folding davit may be rotatably mounted on the bed of a cargo or load-carrying vehicle, such as a van, and has a jib arm which can be swung outboard of the vehicle bed to enable a load to be picked up, raised by a lifting device on the jib arm and then swung in-board of the vehicle bed to deposit the load thereon.

If used in a flat bed vehicle or truck, i.e. no superstructure, the davit can be located at any convenient location on the bed. Where the vehicle is a van, however, with an enclosing superstructure and generally opening at the rear but possibly at a side, or additionally at a side, the folding davit is located adjacent said opening or one of same, which is normally closed by one or more doors (hinged, sliding, shutter or other construction).

It is an object of the present invention to provide a davit which can traverse a load through 360 , can be mounted on a vehicle, e.g. in a van, and which is capable of folding into a compact stowed upright condition when not in use.

According to the present invention there is provided a davit comprising a rotatable upright column, a manually length-adjustable jib arm pivoted to the column for rotation about a horizontal axis, a manually length-adjustable control strut pivotally connected to both the column and the jib arm, the control strut being stowable within the column and the jib arm releasably fastened to the column in substantially parallel relationship thereto when the davit is not in use.

Preferably the column is rotatably supported through the intermediary of bearing means on a baseplate capable of being fastened to a vehicle bed.

It is envisaged that a locking means may be provided releasably to immobilise the column relative to the baseplate.

The column may alternatively be provided with a bottom spigot engageable in a socket to provide the rotational characteristic of the davit.

Preferably, where the davit is used in a van, the socket is flush mounted with the floor of the van and is secured to the chassis of the van.

With this arrangement a single davit can be used in any one of a number of vehicles provided with sockets and there is relatively unrestricted access to the van interior.

The column is preferably of channel configuration open towards the control strut.

The jib arm preferably comprises two relatively slidable parts securable together at predetermined lengths by registering holes therein and releasable locking pin means engaging in said holes.

The control strut also preferably comprises two relatively slidable parts securable together at predetermined lengths by registering holes therein and releasable locking pin means engaging in said holes.

The column may, intermediate its top and bottom, have an apertured bracket extending towards the control strut and adapted to have the jib arm fastened thereto by registration of a hole in the jib arm with the bracket aperture and releasable pin means engaging therein.

The jib arm is preferably pivotal to a maximum position where it subtends with the column an obtuse angle, for example up to 110 .

When the jib arm is fastened to the column bracket the control strut parts are freely slidable relative to one another and are housed within the channel of the column.

The load handling means of the davit may comprise a manually-operated hoist connected to the free end of the jib arm and may be such as is sold under our Registered Trade Mark "MINILIFT". Such hoist may instead of being manually-operated be power operated by, for example, an air drive motor.

The load handling means may alternatively be a conventional pulley-rope-winch arrangement, the pulleys being rotatably mounted at the jib arm ends and the winch on the jib, or a chain block arangement or any other convenient form load raising and lowering arrangement, manually or power driven.

The load handling means may comprise an electric hoist mounted on the jib adjacent the upright column, pulley means for a lifting cable, rope or similar being provided at each end of the jib.

Preferably an electric motor is directly connected to the hoist for driving same.

Preferably the electric motor is connected to an electrical supply via a control unit mounted on the upright column.

The electrical supply may be the vehicle battery.

Preferably the hoist drum is divided into two axial compartments by a plate, one of which is the cable wind-off/wind-on section of the winch drum, while the other accommodates a sufficient number of cable wraps to bind the cable to the drum.

Preferably such number is three.

It will, of course, be manifest that whatever form of load handling means is employed with the davit the actual load lifting component or device is mounted on the davit at the free end of the jib arm.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a folding davit, according to the present invention, in the in-use position within a van; Figure 2 is a plan view of the folding davit; Figure 3 is a side elevation similar to Fig. 1 showing the jib arm and control strut in various positions; Figure 4 is a side elevation of a folding davit in a van with a spigot-and-socket mounting; Figure 5 is a side elevation of a folding davit with an electrically-operated winch; and Figure 6 is a plan view corresponding to Fig. 5. Reference is firstly made to Fig. 1 to 3 of the drawings.

Let us assume the folding davit is fitted to a closed van with rear opening doors. The davit is most likely to be fitted to a rear corner of the van bed adjacent the hinged connection of one of the doors. This will give the jib arm the full width of the van within which to move and operate.

The folding davit comprises a bearing housing 10 (roller, ball or other convenient bearings) which is bolted to the van bed 11 through the intermediary of a baseplate or spreader plate 12 on which the lower end of a vertical column 13 is rotatably supported for 360" rotation. The column 13 is of channel configuration open at face 14.

To the top of the column 13 is secured by welding a pair of spaced cheek plates 15.

A bracket 16 apertured as indicated at 17 is welded to one side of the column 13 intermediate the top and bottom of the latter but nearer the bottom.

A length-adjustable jib arm 18 is pivoted between the cheek plates 15 as indicated at 19.

The jib arm comprises relatively slidable parts 20, 21, the part 20, which is of box cross-section cut away at one end, being pivoted between the cheek plates 15 at 19 as aforesaid, and the part 21, also of box-section, being slidable within the part 20 and which is supported by a cross-pin or roller 22 therein during such sliding movement.

The outer part 20 has a pair of aligned holes at location 23 and the inner part 21 has a pair of aligned holes also at location 23 as shown in Fig. 1 but additional at locations 24, 25.

A selected pair of holes of jib arm part 21 can therefore be manually registered with the pair of holes in jib arm part 20 and the parts 20, 21 releasably secured together by a cross-pin 26 which, in turn, is retained in position by a retaining pin (not shown) engageable in a diametral-bore in the cross-pin 26.

A bracket 27 is secured to the underside of the jib arm part 20 and a control strut 30 is pivoted at one end to this bracket 27, the other end of the control strut 30 being pivoted within the channel of the column 13 adjacent the bottom as indicated at 31.

The control strut 30 comprises a lower tubular (square tube) part 32 and an upper tubular part 33 (also square tube) which is slidable in the lower tubular part 32.

The upper part 33 has a pair of aligned holes at location 34 while the lower part 32 has a pair of aligned holes also at location 34 but additionally at locations 35 to 37. A selected pair of holes on lower strut part 32 can therefore be manually registered with the aligned holes at location 34 in upper strut part 33 to provide a predetermined length of control strut 30. The strut parts 32, 33 are secured in adjusted position by a cross-pin 38 which is itself secured in position by a retaining pin (not shown) locatable in a diametral bore in cross-pin 38.

The load lifting and lowering arrangement associated with the folding davit is in the present invention, a MINILIFT (Registered Trade Mark) selfcontained manually- operated hoist 41 (see Fig. 3).

The arc of movement of the jib arm 18 is illustrated in Fig. 3 and it will be noted that this is in excess of 90 , e.g. up to 110 .

When the davit is out of use the hoist 41 is uncoupled from the jib arm 18, and the cross-pin 38 and its retaining pin (not shown) are removed allowing control strut part 33 to slide down into control strut part 32. This causes the jib arm 18 to pivot downwardly to a vertical position alongside the column 13, the collapsed control strut 30 being accommodated within the channel configuration of the column 13. The jib arm 18 is then secured to the bracket 16 by the cross and retaining pin assembly 38 being passed through aperture 17 and a registering pair of holes in the jib arm 18.

Referring to Fig. 4, the folding davit is substantially as described and illustrated with reference to Fig. 1 and for this reason identical parts have been given the same reference numbers.

In this embodiment, however, the column 13 is provided at its bottom with a spigot 50 which engages in a socket 51 depending from the van floor 52 and secured to van chassis members 53. The socket 51 is supported by a plate 54 bolted to the van floor 52.

With this rotational mounting there is a reduction in the overall height of the davit compared with that of Figs. 1 to 3.

The folding davit of Figs. 5 to 6 is again substantially as described and illustrated with reference to Fig. 1 and again for this reason identical parts have been given the same reference numbers.

In this embodiment an electric winch 60 is mounted on the jib part 20. It is shown bolted to the jib part 20 as indicated at 61 but it may be welded thereto instead.

An electrically operated motor 62 is directly coupled to the winch drum 63 and the motor 62 is electrically connected by wiring (not shown) to a control unit 64 mounted on the column 13.

A pulley 65 is rotatably mounted on the end of the jib part 20 adjacent the column by brackets 66 and a smaller diameter pulley 67 is rotatably mounted at the end of jib part 21 remote from jib part 20.

The lifting cable is indicated at 68 and a ioad-engaging hook at 69.

The winch drum 63 is divided into two axial compartments 70 and 71 by a plate 72. Compartment 70 is the cable wind-off/wind-on compartment while compartment 71 houses three cable wraps which bind the cable 68 to the winch drum 63.

It will be noted that there is no need to remove the winch 60 when the davit is in the folded mode since the winch 60 in no way interfers with the folding action since it will lie outside the upright column 13 (see Fig. 3).

A cable and button control (not shown) for use by the operator is plugged into the control unit 64 to effect operation of the winch.

Alternativeiy, a control system can be wired to the van dashboard via the control unit 64 with an up/down switch on the dashboard or other permanent location.

Claims

1. A davit, especially but not exclusively for use on a vehicle, and comprising a rotatable upright column, a manually length-adjustable jib arm pivoted to the column for rotation about a horizontal axis, a manually length-adjustable control strut pivotally connected to both the column and the jib arm, the control strut being stowable within the column and the jib arm releasably fastened to the column in substantially parallel relationship thereto when the davit is not in use.

2. A davit as claimed in claim 1, in which the column is rotatably supported through the intermediary of bearing means on a baseplate capable of being fastened to a vehicle bed.

3. A davit as claimed in claim 2, in which locking means is provided to immobilise the column relative to the baseplate.

4. A davit as claimed in claim 1 in which the column is provided with a bottom spigot engageable in a socket to provide the rotational characteristic of the davit.

5. A davit as claimed in claim 4 in which, where it is mounted in a van, the socket is flush mounted with the floor of the van and is secured to the chassis of the van.

6. A davit as claimed in any one of claims 1 to 5, in which the column is of channel configuration open towards the control strut.

7. A davit as claimed in any one of claims 1 to 6 in which the jib arm comprises two relatively slidable parts securable together at predetermined lengths by registering holes therein and releasable locking pin means engaging in said holes.

8. A davit as claimed in any one of claims 1 to 7, in which the control strut comprises two relatively slidable parts securable together at predetermined lengths by registering holes therein and releasable locking pin means engaging in said holes.

9. A davit as claimed in any one of claims 1 to 8, in which the column, intermediate its top and bottom, has an apertured bracket extending towards the control strut and adapted to have the jib arm fastened thereto by registration of a hole in the jib arm with the bracket aperture and releasable pin means engaging therein.

10. A davit as claimed in any one of claims 1 to 9 in which the jib arm is pivotal to a maximum position where is subtends with the column an obtuse angle, for example up to 110 .

11. A davit as claimed in any one of claims 1 to 10, comprising a load handling in the form of a manually- operated hoist connected to the free end of the jib arm and may be such as is sold under our Registered Trade Mark "MINILIFT".

12. A davit as claimed in claim 11, in which the hoist is instead power operated.

13. A davit as claimed in any one of claims 1 to 10 comprising a load handling means in the form of a pulley- rope-winch arrangement.

14. A davit as claimed in any one of claims 1 to 10 comprising load handling means in the form of an electric hoist mounted on the jib adjacent the upright column, pulley means for a lifting cable, rope or similar being provided at each end of the jib.

15. A davit as claimed in claim 14, in which an electric motor is directly connected to the hoist for driving same.

16. A davit as claimed in claim 15, in which the electric motor is connected to an electrical supply via a control unit mounted on the upright column.

17. A davit as claimed in any one of claims 14 to 17, in which the hoist drum is divided into two axial compartments by a plate, one of which is the cable wind-off/wind-on section of the winch drum, while the other accommodates a sufficient number of cable wraps to bind the cable to the drum.

18. A davit, especially but not exclusively for use on a vehicle, substantially as hereinbefore described with reference to Figs. 1 to 3 or Fig. 4 or Figs. 5 and 6 of the accompanying drawings.