GB2068844A

GB2068844A - Ramp assemblies for pontoon rafts and ferries

Info

Publication number: GB2068844A
Application number: GB8004437A
Authority: GB
Original assignee: MABEY BRIDGE CO Ltd
Current assignee: MABEY BRIDGE CO Ltd
Priority date: 1980-02-11
Filing date: 1980-02-11
Publication date: 1981-08-19
Also published as: GB2068844B

Abstract

A pontoon structure ramp assembly comprises a ramp (R, R1) of wedge shaped profile which is directly pivotally connected (P) to a pontoon (M). The ramp (R, R1) is additionally coupled to the pontoon, above the level of the direct pivotal connection, but below pontoon deck level by a link (L) which has one end pivotally connected to the pontoon and its other end slidably adjustable relative to the ramp to an extent determined by the position along the link of a member (P) which co-operates with a part (B, N) of the ramp. <IMAGE>

Description

SPECIFICATION Ramp assemblies for pontoon rafts and ferries This invention relates to rafts and ferries which are comprised of pontoons having associated ramps by which vehicles and pedestrians are able to board such rafts or ferries.

When such a raft or ferry is operating, the appropriate ramp is either placed at a fixed angle to suit the bank conditions or, if the landing conditions vary, the ramps can be balanced, by coupling them together, usually above deck level, so that on arrival the appropriate ramp may be made to touch down by a person or persons walking out onto the ramp.

The object of the present invention is to provide a ramp assembly having a simplified adjustment arrangement by reducing the number of component parts and keeping them below deck level.

Thus in accordance with the invention there is proposed a pontoon structure ramp assembly comprising a ramp of wedge-shaped profile which is directly pivotally coupled at its larger end to a pontoon, characterised in that the ramp is additionally coupled to the pontoon, above the level of the direct pivotal connection, but below deck level, by a link which has one end pivotally connected to the pontoon and its other end slidably adjustable relative to the ramp to an extent determined by the position along the link of a member which co-operates with a part of the ramp.

Preferably the link is slidably received in a housing or water-tight box and the member consists of a pin insertable through any of a plurality of holes situated along the link and engageable with a hole or a notch in the housing to fix or de-lirnit the angular position of the ramp relative to the pontoon.

The invention is hereinafter described in more detail by reference to the accompanying drawings, in which: Figure 1 is a simplified general view of a muiti-section raft or ferry with a ramp at each end; Figure 2 is a general view of one form of ramp assembly; Figure 3 illustrates a fixed ramp angle arrangement; and Figures 4, 5 and 6 illustrate an adjustable ramp angle arrangement in three available positions.

Referring now to the drawings, the raft or ferry shown in Fig. 1 has a pontoon comprised of six main units M and six side units S suitably connected together and equipped at each end with a two-section landing ramp R intended to be pivotally connected to the endmost main units M. The mode of pivotal connection of the ramps R to main units M is illustrated by reference to one section of a ramp in Fig. 2. Thus each ramp section R1 is of wedgs shape and has its thick end directly coupled to the adjacent pontoon unit M by a lug and pivot connection P near each of its sides.Directly above these direct couplings the ramp section R1 is indirectly coupled to the unit M by by a straight link L which has its one end slidably received within a watertigh housing or box B which extends mainly within the ramp section. The other end of each Itng: L is directly coupled to the adjacent pontoon unit M by a lug and pivot connection S.

Each link L has along its length a series of three, or other convenient number, of equally spaced holes H which are alternatively intended to receive a locating pin P, and the housing or box B has an outward extension E which is formed on each side with a pinlocating hole M (Fig. 3) and/or a V-profile pin-locating notch N (Figs. 2, 4, 5 and 5).

The ramps R at the pontoon ends ill normally, but not necessarily, be coupled gether Qy a cable and pulley system arranged along the sides of the pontoon so that on@ ramp balances the other ramp until such tire as one ramp becomes loaded whereupon that ramp tilts downwards and the ramp at the other end tilts correspondingly upwards.

Fig. 3 however shows how a ramp may@@ retained at a fixed angular disposition relative to the pontoon by insertion of a pin P through a selected one of the holes H in the linlc L and the holes K in the box extension E. in the situation accordingly the link L acts as a tension and compression link.

Figs. 4, 5 and 6 illustrate three different positions for a balanced ramp as mentioned above although the balancing system is illustrated. In each instance a pin P has been positioned through a different one of tho holes H end acts in conjunction with the profile notch N to restrict the degree of iop- ward tilting movement of the ramp, the lin@.

thus acting only as a compression link.

1. A pontoon structure ramp assembly comprising a ramp of wedge-shapsd pThf:l which is directly pivotally coupled a@ its larger end to a pontoon, characterised in that the ramp is additionally coupled to the pontoon above the level of the direct pivotal connec tion, but below pontoon deck level, by a which has one end pivotally connected to the pontoon and its other end slidably adjustable relative to the ramp to an extent detsrmined by the position along the gink of a member which co-operates witch a part of the ramp.

2. A pontoon structure ramp assembly as claimed in claim 1 wherein the link is slidably received in a housing or water-tight box 3. A pontoon structure ramp assembly as claimed in claim 1 or claim 2 in which the member consists of a pin insertable through any of a plurality of holes situated along the link and engageable with a hole or notch in

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Ramp assemblies for pontoon rafts and ferries This invention relates to rafts and ferries which are comprised of pontoons having associated ramps by which vehicles and pedestrians are able to board such rafts or ferries. When such a raft or ferry is operating, the appropriate ramp is either placed at a fixed angle to suit the bank conditions or, if the landing conditions vary, the ramps can be balanced, by coupling them together, usually above deck level, so that on arrival the appropriate ramp may be made to touch down by a person or persons walking out onto the ramp. The object of the present invention is to provide a ramp assembly having a simplified adjustment arrangement by reducing the number of component parts and keeping them below deck level. Thus in accordance with the invention there is proposed a pontoon structure ramp assembly comprising a ramp of wedge-shaped profile which is directly pivotally coupled at its larger end to a pontoon, characterised in that the ramp is additionally coupled to the pontoon, above the level of the direct pivotal connection, but below deck level, by a link which has one end pivotally connected to the pontoon and its other end slidably adjustable relative to the ramp to an extent determined by the position along the link of a member which co-operates with a part of the ramp. Preferably the link is slidably received in a housing or water-tight box and the member consists of a pin insertable through any of a plurality of holes situated along the link and engageable with a hole or a notch in the housing to fix or de-lirnit the angular position of the ramp relative to the pontoon. The invention is hereinafter described in more detail by reference to the accompanying drawings, in which: Figure 1 is a simplified general view of a muiti-section raft or ferry with a ramp at each end; Figure 2 is a general view of one form of ramp assembly; Figure 3 illustrates a fixed ramp angle arrangement; and Figures 4, 5 and 6 illustrate an adjustable ramp angle arrangement in three available positions. Referring now to the drawings, the raft or ferry shown in Fig. 1 has a pontoon comprised of six main units M and six side units S suitably connected together and equipped at each end with a two-section landing ramp R intended to be pivotally connected to the endmost main units M. The mode of pivotal connection of the ramps R to main units M is illustrated by reference to one section of a ramp in Fig. 2. Thus each ramp section R1 is of wedgs shape and has its thick end directly coupled to the adjacent pontoon unit M by a lug and pivot connection P near each of its sides.Directly above these direct couplings the ramp section R1 is indirectly coupled to the unit M by by a straight link L which has its one end slidably received within a watertigh housing or box B which extends mainly within the ramp section. The other end of each Itng: L is directly coupled to the adjacent pontoon unit M by a lug and pivot connection S. Each link L has along its length a series of three, or other convenient number, of equally spaced holes H which are alternatively intended to receive a locating pin P, and the housing or box B has an outward extension E which is formed on each side with a pinlocating hole M (Fig. 3) and/or a V-profile pin-locating notch N (Figs. 2, 4, 5 and 5). The ramps R at the pontoon ends ill normally, but not necessarily, be coupled gether Qy a cable and pulley system arranged along the sides of the pontoon so that on@ ramp balances the other ramp until such tire as one ramp becomes loaded whereupon that ramp tilts downwards and the ramp at the other end tilts correspondingly upwards. Fig. 3 however shows how a ramp may@@ retained at a fixed angular disposition relative to the pontoon by insertion of a pin P through a selected one of the holes H in the linlc L and the holes K in the box extension E. in the situation accordingly the link L acts as a tension and compression link. Figs. 4, 5 and 6 illustrate three different positions for a balanced ramp as mentioned above although the balancing system is illustrated. In each instance a pin P has been positioned through a different one of tho holes H end acts in conjunction with the profile notch N to restrict the degree of iop- ward tilting movement of the ramp, the lin@. thus acting only as a compression link. CLAIMS

2. A pontoon structure ramp assembly as claimed in claim 1 wherein the link is slidably received in a housing or water-tight box

3. A pontoon structure ramp assembly as claimed in claim 1 or claim 2 in which the member consists of a pin insertable through any of a plurality of holes situated along the link and engageable with a hole or notch in the ramp or in said housing or box to fix or delimit the angular position of the ramp relative to the housing.

4. A pontoon structure ramp assembly constructed and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.