WO1981000236A1

WO1981000236A1 - A coupling assembly for the releasable interconnection of a driving and a driven unit in a transport system

Info

Publication number: WO1981000236A1
Application number: PCT/DK1980/000045
Authority: WO
Inventors: L Benndahl
Original assignee: L Benndahl
Priority date: 1979-07-19
Filing date: 1980-07-17
Publication date: 1981-02-05
Also published as: DK147277B; SE423367B; GB2071591B; DE3049738A1; SE8101641L; DK303279A; DE3049738C2; DK147277C; GB2071591A

Abstract

A coupling assembly for the releasable coupling of a driving and a driven unit in a transport system, preferably of the type in which the driving unit is a self-propelled carriage on an overhead rail member, said carriage having a downwardly extending coupling rod (7) which via a coupling assembly (8) can be coupled to transport carriage on which a bracket (9) with a coupling pin (10) is secured. The coupling assembly is characterized in that it allows a certain lateral mobility in all directions when the coupling assembly (8) transmits tractive forces, and provides for a completely rigid coupling when the coupling assembly (8) transmits compressive forces. The rigid coupling is obtained because on the coupling pin (10) an in an opening for receiving the coupling pin (10) in a coupling pipe (11) there are provided cooperating engagements faces (14, 23 and 16, 24) which define two engagement areas which are sufficiently axially spaced to absorb a certain torque. When the coupling assembly (8) transmits tractive forces said mobility is obtained by provision of cooperating locking means (18, 19) for securing the coupling pin (10) in the coupling pipe (11) in a locking position in which said cooperating engagement faces are spaced.

Description

A coupling assembly for the releasable intercon¬ nection of a driving and a driven unit in a transport system

The invention relates to a coupling assembly for the 5 releasable coupling of a driving and a driven unit in a transport system, preferably of the type in which the driving unit is arranged to run on an overhead rail member, and the driven unit is a transport car¬ riage which is movable on a surface and arranged to 0 be couples to a driving unit, preferably via a coup¬ ling rod, said assembly comprising a coupling pin which is rigidly coupled to one of the two cooperat¬ ing units and has generally a cros-section which de¬ creases gradually or stepwise towards its free end, 5 and comprising a coupling pipe which is rigidly coup¬ led to the other of said two units and has hopper- shaped opening arranged to receive the coupling pin.

Such a transport system is known, e.g. from the Danish Patent Application No. 1498/78 and is used e.g. in

20 goods terminals for the transport of loaded transport carriages to individual determinations along the trans-

- - -port path where the carriages may be disconnected from the drive system and be unloaded and then in empty state be recoupled to the drive system for being

25 returned to a loading location along the transport path which is normally closed. The drive units which move along the overhead rail member are either self- propelled, individually driven units or drive blocks on a chain conveyor which carries the downwardly

30 extending coupling rods.

The known system comprises a coupling assembly which is arranged to connect a coupling rod to a transport carriage in a releasable manner, said assembly being so arranged that the coupled members form a link which is rigid in a vertical plane, while the link has some mobility in a horizontal plane. The latter mobility is excellent when the transport carriage is pulled forwards in the usual manner, and for that matter some mobility in a vertical plane would also be advantageous. However, the mobility is a great drawback when a driving unit brakes and/or particu¬ larly when it negotiates a corner of the overhead rail member because the inertia of the transport carriage and the lateral mobility of the coupling assembly entail that the transport carriage very li- kely runs a distance outside the proper path of move¬ ment before the transport carriage stops.

The object of the invention is to provide a coupling assembly which obviates the drawbacks mentioned above, i.e. a coupling assembly which involves some mobility between the coupled members when the coupling assembly transmits a tractive force, while the coupling assembly is completely rigid in all directions when it transmits compressive forces.

This object is achieved by constructing the assembly as stated in the characterizing portion of claim 1 because when the coupling assembly transmits a tractive force resilience is provided for by the coupling pin being secured against withdrawal from the coupling pipe in a locking position in which the penetration depth of the coupling pin is smaller than the greatest penetration depth, said greatest penetration depth occurring when the coupling assembly transmits compres¬ sive forces and resulting in a completely rigid coup-

O ? t_h WIP ling owing to the hopper-shaped opening in the coupling pipe and the conical coupling pin in connection with at least two axially spaced ring-shaped engagement areas between the members.

The greatest penetration depth is preferably defined by the edge area stated in claim 2, which means that during braking the coupling pin is always aligned with the coupling rod as an exact elongation thereof.

Claim 3 defines a preferred embodiment of the locking means. Owing to the hopper-shaped opening in the coup¬ ling pipe and owing to the axial clearance in said locking position between the coupling pin and the coupling pipe, the members may be coupled together __..even_though the axis of.the coupling pin extends in a certain angular relationship with the axis of ^{" ""}the coupling-rod. This is particularly an advantage when the transport carriage carries a heavy load be¬ cause it may be difficult manually to manoevre the trans¬ port carriage into an exact position with respect to the coupling assembly.

The coupling is additionally facilitated by the fea- _ ,-tures-.stated -in claim 4 which result in an axial mobility of the coupling assembly with respect to the coupling rod so as _vto provide for a relative margin for the positioning of the transport carriage in order for the members to be coupled together.

Claim 5 defines preferred locking means between the coupling assembly and the coupling rod, which locking means may be identical with the locking means between the coupling assembly and the coupling pin, which faci¬ litates the manufacture of the coupling assembly.

O PI The features defined in claim 6 offer the advantage that the locking means between the coupling pipe and both the coupling pin and the coupling rod are si¬ multaneously either engaged or disengaged, depending upon a rotation of the coupling pipe about its axis. Said rotation may be provided by means of the handle mentioned in claim 7 so that the coupling assembly is only to be operated with one hand when it is to be coupled to a transport carriage, while the other hand is free for positioning the control rod of the transport carriage which carries the coupling pin.

The invention will be explained more fully in the fol¬ lowing description of an embodiment with reference to the drawing, in which

fig. 1 shows a part of transport system with a coupling assembly according to the invention,

fig. 2 shows a longitudinal section of an embodiment of the coupling assembly according to the invention,

fig. 3 shows a section taken along the line III-III in fig. 2, while

fig. 4 shows a section taken along the line IV-IV in fig. 2.

Fig 1 shows parts of a transport system of the type for which the coupling assembly of the invention is particularly suitable. The system comprises a plurali¬ ty of transport carriages, such as the carriage 1 which is shown with a load 2 and is arranged to run on a sur¬ face 3. The transport carriage 1 has a steering rod 4 whose free end is formed as a handle (cannot be seen

QMP .. IP in the figure) so that the transport carriage may be driven manually. Normally, however, the transport car¬ riages are driven by means of a plurality of self-propelled carriages, a carriage 5 being shown which runs along an overhead rail member 6 and is arranged to drive a trans¬ port carriage via a coupling rod 7, there being provided a coupling assembly 8. of the invention which is arranged to releasably couple the coupling rod 7 and the control rod 4 together via a bracket 9 with a coupling pin 10.

Fig 2 shows a longitudinal section of the coupling as¬ sembly 8 of the invention. The coupling assembly comprises a coupling pipe 11 which is arranged to receive a variable ..length of the coupling rod 7 which at its end has an en¬ gagement shoulder 12 for cooperation with a stop edge 13 in-the -coupling pipe 11 when the carriage -5 transmits a tractive force through the coupling rod 7 to the trans¬ port carriage-1. This tractive force is transmitted to the transport carriage via locking means which are provided in the other end of the coupling pipe 11 for cooperation with the coupling pin 10, and which will be described more fully below.

In the embodiment shown the coupling pin 10-has a substan- —tially -circular cross-section which gradually decreases towards the end of the coupling pin. The coupling pin 10 has thus a frusto-conical engagement face 14, a sub- . stantially cylindrical portion 15 and a second engage¬ ment face 16 which merges into the tapering end of the coupling pin. To prevent the coupling pin 10 from being pulled out of the coupling pile 11, three spring loaded latch locks are provided, a latch lock 17 being shown -in fig. 2 (see also fig. 3 which shows a section of the locking means taken along the line III-III in fig. 2) . In the embodiment shown the latch locks 17 are cylin- drical, aprat from a cut-out 18 for engagement with a locking face 19 on the coupling pin 10. Each locking face 19 is provided at respective cut-outs 20 (and 20A, 20B for the two other latch locks which are shown in figs. 3 and 4). Each latch lock 17 is disposed in an associated, cylindrical cup 21 and is biased towards the axis of the coupling pipe 11 by means of a spring 22. Each cup 21 is screwed into the coupling pipe 11 by means of threads, substantially perpendicularly to the axis thereof. Owing to the latch locks being main¬ ly cylindrical a simple construction is obtained so that the latches may easily be replaced when they are worn.

The locking means mentioned in the foregoing prevent the coupling pin 10 from being pulled out of the coupling pipe 11 when the transport carriage 1 is towed by a self-propelled carriage 5j but if the carriage 5 brakes the coupling assembly must be capable of absorbing a pressure; this pressure is absorbed as the coupling pin 10 moves a little longer into the coupling pipe 11 until the engagement face 14 engages a corresponding engage¬ ment face 23 in the coupling pipe 11. In addition to the engagement face 23 the coupling pipe has an addition internal engagement face 24 which corresponds to the engagement face 16 of the coupling pin 10 when the coupling pin is inserted to its greatest penetration depth in the coupling pipe 11.

The end of the coupling pipe 11 through which the coupling rod 7 is received, is provided with three latch locks, a latch lock 25 being shown, which in the shown embodiment is identical with the latch locks described above for cooperation with the coupling pin 10 and each has a corresponding compression spring and screw cup. The latch locks 25 are arranged to cooperate with re¬

OM spective locking faces 26 of the coupling rod 7, at least when the coupling assembly is to transmit a com- pressive force. Like the locking faces 19, the locking faces 26 are provided at respective cut-outs 27 in the coupling rod 7; it will readily be appreciated that there are three such cut-outs 27 (in fig. 2 the dash- and-dot line indicates one of the other cut-outs 20A and 27A on the coupling pin and the coupling rod, re¬ spectively). ¥hen the coupling rod 7 is moved to the right in fig. 2 until the engagement shoulder 12 enga¬ ges the stop edge 13, the latch locks 25 move down¬ wards into the respective cut-outs 27 so that the sec¬ tion IV-IV shown in fig. 2 is identical with the section shown in fig. 3, and so that the coupling assembly can absorb compressive forces by the engagement of the latch locks 25 with the respective locking faces 26. For purposes of illustration, the coupling rod 7 extends in fig. 2 a distance into the coupling pipe 11, and in this position the latch locks 25 assume the position shown in fig. 4 where the distance from the axis of the coupling pipe 11 is greatest.

The operation of the coupling assembly of the invention will now be explained more fully with reference to figs. 1-4. When a transport carriage 1 carries a load 2 and is to be transported over a large distance by means of the transport system, the transport carriage is manual¬ ly moved below a free carriage 5 on the rail member 6. When the carriage 5 is free, the coupling rod 7 is pre¬ ferably pivoted to the position shown by a dash-and-dot line in fig. 1, e.g. by means of gas springs in the

^•carriage 5. The coupling rod 7 is extended downwards preferably by gripping a handle 28, which is secured transversely to the coupling pipe 11, with one hand, while the steering rod 4 is held with the other hand

OMPI , IPO - so that the coupling rod 7 and the coupling pin 10 are flush, and then the coupling pipe 11 is moved obliquely downwards into engagement with the coupling pin.

It should be noted here that the cut-outs 23 and 27 in the coupling pin 10 and the coupling rod 7_» respectively are disposed so as to be flush in pairs, corresponding to the latch locks 17 and 25 being located in pairs in respective axial planes for the- coupling pipe 11. This position allows the coupling assembly of the invention to be released by rotating the coupling pipe 11 about its longitudinal axis by means of the handle 28 (in the shown embodiment in which three latch locks are provi¬ ded at either end of the coupling pipe, the rotation amounts to 60°). The rotation is shown in figs. 3 and 4, fig. 3 showing a section of the coupling assembly in a locking position in which the latch locks engage the respective locking faces, fig. 4 showing a section like fig. 3, but with the coupling pipe 11 rotated through an angle of 60° so that the latch locks are pressed radially outwardly to clear the locking faces 19 which allows the coupling pin 10 to be removed from the coupling pipe 11 and the coupling rod 7 to be introduced further into the coupling pipe 11. At the same time as the coupling rod 7 on a free carriage 5 is moved down- wards, as explained above, from the position shown by a dash-and-dot line (fig. 1) to the position,shown by a full line, said angular- rotation is briefly imparte to the handle 28 so that the coupling assembly may be pushed upwards to the greatest penetration depth of the coupling rod 7 into it, and when the coupling pin 10 is flush with the coupling rod 7 the coupling assembly is moved downwards into engagement with the coupling pin 10. Then the carriage 5 is started and the tractive force in the coupling rod 7 is transmitted to the

OMPI transport carriage via the engagement shoulder 12 and the engagement stop 13_> and the latch locks 17 and locking faces 19, respectively.

During transport several brakings take place, e.g. to avoid collisions. Seen from the transport carriage a curve in the track member 6 also acts as a braking, and here it is of particular importance that the coupling assembly ridigly couples the coupling rod 7 and the control rod 4. This rigid coupling is provided for by ihe coupling assembly of the invention, which is shown best in fig. 2. During breaking the coupling pin 10 bottoms, as mentioned, in the coupling pipe 11 so that the engagement faces 14 and 16, respectively, of the coupling pin engage the engagement faces 23, and 24, _.respectively, of the coupling pipe 11, providing for the absorption of a torque perpendicular to the axis of —the coupling pipe 11. A corresponding torque can be absorbed at the other end of the coupling pipe 11 be¬ cause the internal engagenemt of the coupling rod 7 in the coupling pipe 11 has a sufficient axial length (the sum of the length of the opening in the coupling pipe 11 for receiving the coupling rod 7 and the length of an end piece 29 of the couplingrod7). During brak¬ ing this rigid coupling brings about a well-defined path of movement for the transport carriage 1 in a curve and prevents the driving wheel from being turned during braking on a straight stretch.

When the transport carriage 1 is to be disengaged from the coupling rod 7, said rotation is imparted to the handle 28; when the carriage 5 is running said rotation automatically brings about a separation and when the carriage 5 is stopped the rotation allows the coupling assembly 8 manually to be moved out of and disengaged

-gTRE ?j

OMPI from the coupling pin 10.

In addition to the operating properties already mention¬ ed the coupling assembly of the invention offers other advantages, particularly of a nature beneficial to the 5 job. Firstly, it should be noted that the coupling of the transport carriage and the coupling rod, explained above, does not involve any risk of an operative getting his hands jammed, which might be dangeroud as the transport carriage often carries a load of one ton. It

10 may also be difficult manually to manoeuvre such a heavy transport carriage into a position in which the coupling pin 10 is exactly flush with the coupling rod 7. This problem, too, is solved by the coupling assembly of the invention, it being shown in fig. 2 that there is

15 some axial spacing between the engagement faces 14, 23 and 16, 24 when the latch locks 17 cooperate with the locking faces 19. This feature combined with the hopper-shaped opening in the coupling pipe 11 for receiving the coupling pin 10 means that the coupling

20 pin 10 and the coupling pipe 11 may engage each other even though these members are not exactly flush with each other.

It will be appreciated that the important features of the shown embodiment of the coupling assembly of the " 25 invention consists in the hopper-shaped opening in the coupling pipe 11 for receiving the coupling pin, which has a cross-section which corresponds substantially to the opening at least along two axially spaced areas (the engagement faces 14, 23 and 16, 24). Another im- 30 portant feature is that the latch locks engage the coupling pin in a position in which there is some axial spacing between said cooperating engagement faces, but it will be appreciated that other locking means than

OMPI the shown latch locks may be used, it being possible to use e.g. ball couplings.

In the shown embodiment the coupling- pin and the coupling rod are circular in cross section, which makes it possible to clear the locking means merely by rotating the coupling pipe, but it will be appreciated that the pin and the rod may have other cross-sectional configurations particularly in connection with other forms of locking means. Nor is the invention restricted to the locking pin being carried precisely by the transport carriage as the pin may alterna¬ tively be disposed at the end of the coupling rod, whilethe coupling pipe might be slidably mounted on the transport carriage.

OMPI

Claims

3. A coupling assembly according to claim 1 or 2, c h a r a c t e r i z e d in that the cross-section of the coupling pin (10) is substantially circular and has a plurality of cut-outs (20)^' which define respective, not continuous locking faces (19) which face said one unit and are arranged to cooperate, in the locking position, with their respective latch locks (17) which are fitted in the coupling pipe (11) and are movable in a plane transversely to and spring-loaded (22) towards the axis of the coupling pipe (11).

4. A coupling assembly according to claim 1, 2 or 3_» wherein the coupling pin is secured to a transport carriage and a coupling rod is coupled to the driving unit, c h a r a c t e r i z e d in that the coupling pipe (11) is arranged to receive a longitudinally variable length of the coupling rod (7) through its end ^■ opposite the said opening, and that additional releasable locking means (25, 26) are provided which, in another locking position, are arranged to secure the coupling rod (7) with a relatively small penetration depth with respect to the coupling pipe (11) , said coupling pipe and coupling rod being radially closely spaced in the other locking position at least along two axially spaced annular enga¬ gement areas.

5- A coupling assembly according to claim 4, wherein the engagement areas between-the coupling rod and the coupling pipe are circular, c h a r a c t e r i z e d in that the additional locking means comprise a radial projection (12) on the coupling rod adjacent its end received in the coupling pipe for cooperation with an abutment (13) in the coupling pipe (11) and comprises a plurality of cut-outs (27) in the coupling rod (7) to define respective, not continuous locking faces (26) which face the projection (12) and are arranged to co¬ operate in the other locking position with their respective latch locks (25) which are ^"fitted in the coupling pipe (11), said latch locks being movable trans versely to and spring loaded towards the axis of the coupling pipe (11).

6. A coupling assembly according to claim 5, c h a r a c t e r i z e d in that the latch locks (17) of the coupling pin (10) and the latch locks (25) of the coupling rod (7) are disposed in the same spaced angular relationship with their respective ends of the coupling pipe (11) so that both of said locking positions are obtained in a predetermined angular position of the coupling pipe (11) about its axis with respect to the coupling pin (10) and the coupling rod (7) .

7. A coupling assembly according to claim 6, ^• c h a r a c t e r i z e d in that the coupling pipe (11) has a handle (28) mounted transversely thereto, by means of which the coupling pipe may be rotated away from the said, predetermined angular position.

O PI

_Λ_ WIPO