GB2267889A - Lift for cellars and the like - Google Patents

Abstract

A cellar lift including a frame 12 slidably supporting a carriage 27 having barrel supporting members 25. The carriage 27 is raised and lowered by a cable 20 which passes around a drum 36 to which a spiral cam 38 is rigidly connected. At the carriage's bottom position a carriage mounter roller 32 which normally engages the frame 12 reaches a position where it can pass under the bottom of the frame 12 and the cam 38 engages a cam follower stop 45. Further release of the cable 40 allows the cable to be wound onto the drum 36 so that the drum and the spiral cam 28 can rotate thus lowering the members 25 to the ground 17, facilitating the unloading or loading of a barrel. A hydraulically actuated embodiment is also disclosed (Figs. 5 and 6, not shown). <IMAGE>

Description

LIFT FOR CELLARS AND THE LIKE This invention relates to a goods lift, and in particular to a lift suitable for use in cellars, for example for delivering beer kegs and other bulky items to the cellar of a public house, restaurant or similar premises.

In the past when delivering beer kegs to a cellar, the kegs have been dropped or rolled down a steep chute or ladder onto a suitable cushion such as a pile of sacking.

New regulations coming into force are likely to outlaw this practice, for reasons of safety.

Many licensed premises will be faced with the problem that their cellar is small and has restricted access through an external trapdoor. There is therefore a need for lift of simple and compact construction which can be installed within the limited confines of an existing cellar with a minimum of adaptation. A problem which arises in this context is that a lift has a platform or fork which must be firmly supported from underneath but which must be capable of depositing the keg on to the floor without being dropped. Since it would be undesirably expensive to excavate a hole in the floor to accommodate the lift mechanism and allow the lift platform to reach the floor, there is a need for an alternative mechanism by which the kegs can be transferred from the platform to the floor.

The present invention seeks to solve this problems by providing a lift with a load-carrying member such as a fork or platform which, at or near the bottom of its travel, can be tilted downwardly so that kegs can be rolled off it straight on to the floor. This tilting should be controlled rather than precipitate, and should preferably be a simple extension of the downward movement of the platform.

The present invention consists of a lift comprising: a frame; a carriage mounted on the frame for up and down movement between top and bottom positions and including a load-carrying member such as a platform or fork; means for raising and lowering the carriage on the frame, said means including an elongate flexible member such as a rope, cable or chain connected at one end to the carriage; wherein the load-carrying member, in the bottom position of the carriage, is pivotable relative to the frame between a load-carrying position and a tilted unloading position, but above said bottom position is retained in its load-carrying position and prevented from pivoting by engagement with the frame.

Preferably the lift includes a winding member mounted for rotation on the carriage and arranged to take up a length of the elongate member as it rotates.

Conveniently with the load-carrying member in its load-carrying position the winding member engages a stop on the carriage to prevent rotation in a direction to unwind the elongate member therefrom so that the carriage can be hauled upwards by the elongate member, Preferably the lift also includes a cam mounted on the carriage and constrained to rotate as the winding member rotates, and, in the bottom position, the load-carrying member is no longer prevented from pivoting by engagement with the frame, and tends under gravity to pivot towards its unloading position but at the same time urges the cam against a fixed cam follower, so that pivoting can proceed only as more of the elongate member is fed to the carriage, the winding member rotating in a direction to take up the elongate member and to rotate the cam in a direction to allow the load-carrying member to pivot.

The winding member may be in the form of one or more discs or drums, mounted for rotation about a horizontal axis. The cam is preferably mounted coaxially with the winding member on a common shaft, and may be of a type having a spiral cam surface.

So as to avoid the necessity of providing separate runners for the carriage, the frame preferably includes two inwardly facing channel section pillars with which the carriage engages.

In an alternative solution according to the invention particularly suitable where the frame cannot be positioned vertically the load carrying member includes a guide member which is engageable with the frame above said bottom position and disengages therefrom at or near said bottom position and engages a tilt control member which is actuable so as to permit tilting of the load-carrying member into the unloading position.

Preferably a pressure sensor is provided in the hydraulic circuit driving the elongate flexible member which detects a rise in pressure resulting from the load carrying member coming into contact with the tilt control member. This sensor then causes a flow of pressurised fluid to be diverted to the actuator so as to tilt the load carrying member to the unloading position.

Alternatively proximity sensor may be provided and actuation of said tilt control member is commenced when the proximity sensor senses the presence of the load-carrying member at or near the said bottom position.

More preferably upon said means for raising the carriage being actuated to raise the carriage the tilt control member is first moved so as to move the load-carrying member into the load-carrying position.

The elongate flexible member may suitably be in the form of a steel cable or chain, pulled up and down by means of an electric and/or hydraulic motor. Alternatively, it may be hand operated by means of a winch.

Preferred embodiments of the invention will now be described with reference to the accompanying drawings wherein: FIG 1 is a side elevation of a cellar lift in accordance with the present invention, partly in cross-section; FIG 2 is a front elevation, partly in section, of the lift of Fig 1 in its bottom position; FIG 3 is a partial view similar to that of Fig 1 with the lift platform at the start of its pivoting movement; FIG 4 is a view similar to that of Fig 1 with the lift platform pivoted downwardly into its unloading position; Fig 5 is a side elevation of the lower end of an alternative lift in accordance with the present invention; Fig 6 is a view similar to Figure 5 with the loadcarrying member in the unloading position.

Referring first to Figs 1 and 2, there is shown a lift for lowering a beer keg or the like (18) from a upper surface (16) to a lower surface (17), for example from an outside pavement to a cellar floor. The lift includes a frame comprising a pair of vertical pillars (12) linked by cross-members (14, 15). The cross-members (14) are in the form of flat plates welded to the pillars, and the cross-member (15), requiring greater rigidity as will be described below, is in the form of a box-section beam.

The frame also includes a pair of spaced vertical cam plates (20), each secured by welding to the cross-members (14, 15) and extending from a position immediately below the top surface (16) to a position somewhat above the floor (17). The front edges of these plates form vertical cam surfaces (21). At their lower ends, the plates (20) have curved cam surfaces (22).

The pillars (12) are of channel-shaped cross-section and face inwardly towards one another, each accommodating a runner (28), for example in the form of a wheel, of a carriage generally indicated by (24) and having a load-carrying member in the form of a fork comprising two outer plates (25) which are mounted on the runners (28), and which support the load, these outer plates being connected together by means of a pair of box-section members (26) extending between them. These box-section members also support a pair of inner plates (27) which again are spaced from one another but which are closer together and located between the cam plates (20).

The inner plates (27) support at their lower end a horizontal cylindrical shaft (30) at each end of which is mounted a roller (32) arrange to bear against an edge of a respective one of the two cam plates (20).

The carriage (24) can pivot about a horizontal axis extending through the runners (28), but when the carriage is above its bottom position, as shown in Fig 1, it cannot pivot downwardly from the load-carrying position shown because the rollers (32) abut against the vertical cam surfaces (21) of the cam plates (20). When however the carriage is lowered to the position shown in Figs 2 and 3 the rollers (32) are clear of the vertical surfaces (21) of the cam plates and are thus able to run under them, bearing again the curved lower cam surfaces (22) to enable the carriage to pivot downwards as shown in Fig 4 to a position in which the keg carried by the fork can simply be rolled off on to the floor (17).

Adjacent their upper edges, the plates (27) carry a shaft (34) which is mounted in bearings (35) and are thus rotatable relative to the plates. At each end of the shaft is a wheel (36) having a circumferential channel. Secured to each of these wheels is a cable (40) which can be wound on to and off the wheel as the latter rotates, the cable being received in the circumferential channel and having its end permanently secured to the wheel. The cables (40) extend vertically between the pillars (12) and over respective pulleys (42) rotatably mounted in bearings in the upper ends of the cam plates (20). The cables (40) are used to raise and lower the carriage, for example by means of an electric winch.

At a central position on the shaft (34) is mounted a cam (38) having a spiral outer surface (39) as shown in Fig 1. The cam is also fixedly mounted on the shaft so that it is constrained to rotate with the wheels (36) about the common axis provided by the shaft.

It can be seen that, in the absence of any constraint, drawing the cables (40) upwardly will rotate the wheels (36) anticlockwise as seen in Fig 1. Such rotation is however limited by stops (42, 43) provided on respective opposing surfaces of at least one of the plates (27) and one of the wheels (36). These stops come into abutment when the carriage is in the load carrying position shown in Fig 1 that the wheels (36) are prevented from rotating and the carriage can be raised by means of the cables (40).

The operation of the lift is as follows. The carriage (24) in the load-carrying position shown in Fig 1, is movable between the bottom position shown in Fig 3 and a top position in which the upper surfaces of the plates (25) adjacent the pillars (12), are level with or immediately below the upper surface (16) so that beer kegs or the like can be easily rolled onto them. These plates are upwardly canted at their free ends, to retain the kegs thereon. By paying out the cables (40) from an electric winch or the like, the carriage can be lowered.

During the travel of the carriage, the load-carrying fork is prevented from tilting into its unloading position by abutment of the rollers (32) against the vertical cam surfaces (21).

As the carriage (24) is lowered to the position shown in Fig 1, immediately above its bottom position, a substantially straight surface (46) of the cam (38) engages a cam follower (45) in the form of a roller supported by the box section beam (15) for rotation about a fixed axis.

As the carriage is lowered further to the position shown in Fig 3, the runners (28) come to rest on stop surfaces (29) on the insides of the channels in the pillars (12). In this position, the rollers (32) are clear of the vertical front cam surfaces of the plates (20), and thus in a position to run under these plates to allow the load-carrying plates (25) to pivot downwardly, under the influence of gravity, about its pivotal mounting in the runner (28). If the winch is stopped at this point, the carriage is still held against pivoting since the wheel (36 and hence the cam (38) are held against rotation in one direction by the tension in the cables (40) and in the opposite direction by the mutual abutment of stops (42) and (43).If however the winch is operated further to pay out slightly more cable, the wheels (36) can start to rotate in a clockwise direction as seen in the drawings so that the cam (38) also rotates. As the cam rotates, its surface remains in contact with the cam follower (45) and, because of the spiral shape of the cam surface, the distance between the axis of shaft (34) and the axis of the cam follower (45) begins to decrease. The carriage thus begins to pivot about the runners (28) in an anticlockwise direction as seen in the drawings, with the rollers (32) running along the cam surfaces (22) which form the bottom edges of the plates (20). The pivoting is however controlled by the rate at which the cables (4) are paid out fom the winch, and can be stopped at any stage simply by stopping the winch.

Eventually the carriage (24) reaches its unloading position shown in Fig 4, in which the outer ends of the plates (25) are on the ground, the shaft (34) is as close as it can be to the cam follower (45) and the rollers (32) have passed right under the cam plates (20). It can also be seen that the stop (43) is now adjacent the opposite end of stop (42) to that which it engages when the carriage is in its load-carrying position.

From the position shown in Fig 4. the carriage can be pulled back up to is load-carrying position simply by reversing the winch to haul the cables (40) back up. From the position shown in Fig 4, the wheels (36) are rotated anticlockwise so that rotation of the cam once again pushes the shaft (34), and hence the wheels (36), the plates (27) and the plates (25), away from the cam follower (45). It can be seen that in this connection there is a considerable mechanical advantage in that the wheels (36) are turned through more than 3000 whereas the load-carrying members rise only through about 300.

As the cables are hauled up further, stop (43) mounted on the wheels (36) comes back into engagement with stops (42) mounted on plates (27), preventing further rotation of the wheels (36). The carriage is now back in its load-carrying position, and if the cables (40) are hauled up further, the wheels (36), unable to rotate further to unwind more cable, instead rise with the cables and the carriage (24) can be hauled back to its top position.

There is thus provided a simple and compact apparatus which can be installed in existing cellars with relatively limited trapdoor access, to lower beer kegs and the like gently to a cellar floor and unload them onto the floor without dropping or bumping so that they can be rolled off the fork or platform to their storage position.

Fig 6 shows a side view of the lower end of an alternative lift according to the invention. The lift includes a frame made up from two parallel channel section pillars (112) interconnected with cross members (114) with their open sides facing each other. A carriage (124) including a pair of load-carrying members (125) is pivotably and translatably supported on the pillars by means of a pair of runner wheels (128). Each load-carrying member has an outwardly projected guide pin (200) which bears on an upper surface (121) of a frame pillar when the carriage is above its bottom position, as shown at A in Figure 5.

The lower end of the frame each pillar is supported by a lift support leg (202). Downwardly extending from pillar (112) is a lug which centrally supports a tiltcontrol member (202) by means of a pin (206). The upper end of the tilt-control member is positioned to be engaged by guide pin (200) when the carriage reaches the bottom position. The lower end of the tilt-control member is connected to the ram of a hydraulic actuator (204) by means of a second pin (206). The upper end of the actuator is connected to the associated frame pillar (112) by a third pin (210).A continuous chain (140) driven by an electrically powered hydraulic motor (142) driven by pressurised oil from an electrically powered hydraulic pump (144) not shown, is provided to translate the carriage with respect to the frame. ,A pressure sensor, not shown, associated with a hydraulic circuit associated with the hydraulic motor (142) is actuable so as to divert a flow of pressurised hydraulic fluid from the hydraulic motor (142) through a pipe (146) to the hydraulic actuator (204).

The operation of the second embodiment will now be described with reference to Figures 5 and 6.

As the chain (140) lowers the carriage (124) down the frame, the guide pins (200) bear on the upper surface (121) of the frame pillars (112), as shown at A in Figure 5.

As the carriage (124) reaches the bottom of the frame, one guide pin leaves the upper surface of the pillar (112) and engages the tilt control member (202). At this point the pressure in the hydraulic circuit driving the hydraulic motor (142) rises. This rise in pressure is sensed by the pressure sensor and the flow of pressurised fluid is diverted to the actuator (204) through pipe (146) and commences retraction of the hydraulic actuator (204).

This causes the guide pin to move along the upper surface of the tilt-control member permitting the load-carrying members to move to the unloaded position shown in Figure 6.

When there is a requirement to raise the carriage (124), the hydraulic actuator (204) is first extended to the position shown at B in Figure 5 prior to rotating the continuous chain (140) so as to raise the carriage. The sequencing of these operations is effected by any suitable means.

While only one actuator and tilt-control member have been described the arrangement may be duplicated at the lower end of the other frame pillar (112).

Claims (13)

1. A lift comprising: a frame; a carriage mounted on the frame for up and down movement between top and bottom positions and including a load-carrying member; means for raising and lowering the carriage on the frame, said means including an elongate flexible member; wherein the load-carrying member, in the bottom position of the carriage, is pivotable relative to the frame between a load-carrying position and a tilted unloading position, but above said bottom position is retained in its load-carrying positioned and prevented from pivoting by engagement with the frame.

2. A lift as claimed in claim 1 including a winding member mounted for rotation on the carriage and arranged to take up a length of the elongate member as it rotates.

3. A lift as claimed in claim 2 wherein with the load carrying member in its load-carrying position the winding member engages a stop on the carriage to prevent rotation in a direction to unwind the elongate member therefrom so that the carriage can be hauled upwards by the elongate member.

4. A lift as claimed in claims 2 or 3 including a cam mounted on the carriage which is constrained to rotate as the winding member rotates.

5. A lift as claimed in claim 4 wherein, in the bottom position, the load-carrying member is no longer prevented from pivoting by engagement with the frame, and tends under gravity to pivot towards its unloading position but at the same time urges the cam against a fixed cam follower, so that pivoting can proceed only as more of the elongate member is fed to the carriage, the winding member rotating in a direction to take up the elongate member and to rotate the cam in a direction to allow the load-carrying member to pivot.

6. A lift as claimed in claims 4 or 5 wherein the cam is mounted coaxially with the winding member on a common shaft.

7. A lift as claimed in claims 4, 5 or 6 wherein the cam has a spiral cam surface.

8. A lift as claimed in any of claims 2 to 7 wherein the winding member comprises one or more discs or drums mounted for rotation about a horizontal axis.

9. A lift as claimed in any preceding claim wherein the frame includes two inwardly facing channel-section pillars with which the carriage engages.

10. A lift as claimed in claim l wherein the load-carrying member includes a guide member which is engageable with the frame above said bottom position and disengages therefrom at said bottom position and engages a tilt control member which is actuable so as to permit tilting of the load-carrying member into the unloading position.

11. A lift as claimed in claim 10 wherein the means for raising and lowering the carriage includes hydraulic drive means and a sensor is provided to sense a rise in pressure in an associated hydraulic circuit caused by the carriage being at or near said bottom position so as to cause said actuation of the tilt control member.

12. A lift as claimed in claims 10 or 11 wherein upon said means for raising the carriage being actuated to raise the carriage the tilt control member is first moved so as to move the load-carrying member into the load-carrying position.

13. A lift substantially as described with reference to Figures 1 to 4 or Figures 5 and 6.