A connecting mechanism for connecting a mobile unit to a basic unit

Abstract: A connecting mechanism for connecting a functional part (14) of a mobile unit (8) to a basic unit (1). The mobile unit (8) consists of a mobile bottom part (10) provided with compression springs (12) on which the functional part (14) rests. The functional part is provided with connecting elements which can co-operate with connecting elements on the basic unit with the compression springs (12) compressed. The connecting elements are formed by a hook (4) and a roller (15) which forms a cylindrical contact surface (6), each on the underside of the units (1, 8), and by surfaces (16, 5) forming a vertical contact surface (7, 18) at the top of the units (1, 8).

Description: The invention relates to a connecting mechanism for connecting a functional part of a mobile unit to a basic unit, comprising at least one first set of connecting elements formed by a first connecting element connected to the basic unit and a second connecting element connected to the functional part of the mobile unit, which second connecting element can co-operate with the first connecting element in order functionally to connect the units in a required position. A connecting mechanism of this kind is known from US-A-4 433 881, which describes a mechanism for connecting mobile units wherein the connecting elements are formed by docking pins on one unit and docking channels on the other unit. To manoeuvre each docking pin in an associated docking channel when positioning a mobile unit with respect to a fixed unit, the mobile unit in this known mechanism must be lifted at its side situated opposite the fixed unit. This requires considerable effort, particularly if the units for connection are heavy. Particularly if the person making the connection is standing on the side of the mobile unit opposite the side for connection, and this is the easiest for the connection, then it is difficult for the person to make the connection, which is then not readily visible. The object of the invention is to provide a connecting mechanism of the type referred to in the preamble without these disadvantages. To this end, according to the invention, the mobile unit comprises a mobile bottom part and thereabove a functional part which rests resiliently on the bottom part by means of at least one resilient element between said parts and the functional part of the mobile unit is movable between a first position in which the second connecting element is at a different level from the first connecting element and the first and second connecting elements are adapted to be placed exactly above one another and a second position in which the connecting element is in contact, in a contact surface, with the second connecting element for fixing the units in place relatively to one another in the vertical direction and in the direction in which they are movable towards one another. Consequently, irrespective of the position of the mobile bottom part, when it is resting on a floor having a normal unevenness, the functional part can be positioned appropriately with respect to the basic unit even if the basic unit rests on a floor of normal unevenness. If the resilient element presses the second connecting element on the mobile unit against the first connecting element on the basic unit during the connection of the functional part of the mobile unit and the basic unit, the connection is achieved by holding the mobile unit pressed down against the spring action during engagement and releasing of this unit when it abuts the basic unit, in which connected condition the mobile unit continues to rest on the floor so that there is no risk of the connected units tipping. Other features and advantages of the invention are explained hereinafter with reference to the accompanying drawings wherein: Fig. 1 shows a first embodiment of the mobile unit in the free- standing state. Fig. 2 is a first embodiment of the basic unit and mobile unit according to Fig. 1 in the disconnected state. Fig. 3 shows the basic unit and mobile unit according to Fig. 2 in the connected state on a flat floor. Fig. 4 shows the basic unit and mobile unit according to Fig. 2 in the connected state on a floor which is not flat. Fig. 5 is a detail of a second embodiment of the basic unit and mobile unit in the disconnected and connected state on a flat floor. Fig. 6 is the detail according to Fig. 5 with the basic unit in a raised position. Fig. 7 is the detail according to Fig. 5 with the basic unit in a lowered position. Fig. 8 shows an operating mechanism for establishing an electrical connection between the basic unit and the mobile unit and the mechanical latching of the connection between said units, in a position in which the electrical connection and latching have not yet been effected. Fig. 9 shows the operating mechanism according to Fig. 8 in a position in which the electrical connection and latching have been effected. Fig. 10 is a detail of the basic unit in top plan view with a switch establishing the electrical connection between the basic unit and the mobile unit. Fig. 11 is the detail of Fig. 10 in side elevation. Fig. 12 is a top plan view on the line XII-XII in Fig. 8, shown in a first position and Fig. 13 is the top plan view of Fig. 12 in a second position. The embodiment of a mechanism according to the invention shown in Figs. 1 to 4 comprises a basic unit 1 shown in Figs. 2 to 4, which can be placed in a fixed position, e.g. by locking the wheels 2 on which the basic unit 1 rests. A connecting element in the form of a hook 4 is secured to a side wall 3 of the basic unit 1 near each bottom corner and a hook-shaped recess 5 is formed in the middle of the top. Hook 4 has a downwardly directed convex contact surface 6 and recess 5 has a contact surface 7 extending towards the basic unit. The basic unit can be brought into contact with a mobile unit 8 for coupling to the basic unit by means of these contact surfaces 6 and 7 on the basic unit 1, the mobile unit 8 being shown in a free-standing state in Fig. 1. The mobile unit 8 consists of a bottom part 10 having castors 11 to enable it to move towards the basic unit 1. Compression springs 12 rest on the bottom part 10, one at each of the four corners thereof. Another part 14 of the mobile unit 8 rests on the springs 12. This part 14 contains functional components which must be capable of co-operating mechanically and/or electrically with functional components in the basic unit 1. Such co-operation may comprise the part 14 of the mobile unit 8 - which will hereinafter be referred to as the functional part - containing a stock of receiving material and the basic unit 1 is a printing machine for printing images on the receiving material supplied from the functional part 14. For this purpose, the transport paths for receiving material in the functional part 14 and in the basic unit 1 must accurately mate when the basic unit 1 and mobile unit 8 are connected together, an electrical power supply also being branched off from the basic unit 1 for the mobile unit 8 when the units 1 and 8 are connected. On the side where it is adapted to be connected to the basic unit 1, the functional part 14 carries near each bottom corner a connecting element in the form of a freely rotatable roller 15 which fits in the convex contact surface 6 of the hook 4 on the basic unit. The functional part 14 of the mobile unit 8 also carries in the middle at the top a hook 16 which fits in the recess 5 formed in the basic unit 1. Hook 16 has a contact surface 18 remote from the mobile unit 8, which contact surface, in the connected state of the units 1 and 8 is in contact with the contact surface 7 formed in the recess 5 as will be explained in detail hereinafter. Hook 16 has a contact surface 19 opposite contact surface 18 and recess 5 has a contact surface 9 opposite contact surface 7, which contact surfaces 9 and 19 come into contact with one another when pressure is applied from above to the functional part 14 in the connected state of the units. Contact surfaces 9 and 19 prevent the units from being pressed apart from one another at the top in the coupled condition. Two pins 20 and 21 are fixed to the bottom part 10 of the mobile unit 8. The middle of a lever 22 is pivotally secured on pin 20 and the middle of a lever 23 is pivotally secured on pin 21. One end 25 of lever 23 carries a pin 26 fitting in the forked end 27 of lever 22 in order to couple the movement of the ends 25 and 27 when one of the levers 22 or 23 turns. The other end of lever 22 is pivotally connected by a pin 28 to the end of an L-shaped arm 30 and the other end of lever 23 is pivotally connected by a pin 29 to an L-shaped arm 31. Each of the arms 30 and 31 projects upwards from the bottom part 10, where it has a bent end 32, 33 respectively, which is situated just above stops 34 and 35 respectively on the functional part 14. Arms 30 and 31 are vertically movable in a rectilinear guide (not shown) to a position shown in Figs. 1 and 2, in which either springs 12 press the stops 34 and 35 against the ends 32 and 33, holding the functional part 14 in a lifted position with respect to the bottom part 10 in so doing, as shown in Fig. 1, or the ends 32 and 33 pull the stops 34 and 35 down against the action of springs 12 as shown in Fig. 2. By means of a latching mechanism described hereinafter with reference to Figs. 8 - 9, 12 and 13, the functional part 14 of the mobile unit 8 can be pressed down beforehand and be latched in the pressed-down position, the latching continuing until the mobile unit 8 reaches the position shown in Fig. 2. As a result, during transport and engagement the mobile unit 8 is more stable. As will be explained hereinafter with reference to Figs. 3 and 4, the stops 34 and 35 can also occupy a position in which they are free of the ends 32 and 33. A pin 37 disposed a short distance above pin 21 is secured to lever 23. Together with pins 26 and 29 the pins 21 and 37 form a rectilinear guide for an operating lever 38. A collar 39 at the end of this lever 38 forms a stop which prevents the lever 38 from being pulled out between the pins 21 and 37. The operating lever 38 also rests on pin 29 and is movable between the broken-line position in which the lever 38 is received completely in the bottom part 10 and a solid-line position in which the collar 39 abuts the pins 21 and 37 and a part of the operating lever 38 which functions as a foot pedal projects from the bottom part 10. The operation of the mechanism shown in Figs. 1 to 4 is as follows: In the free-standing position of the mobile unit shown in Fig. 1, the operating lever 38 is retracted and the mobile unit 8 is moved in this condition up to the basic unit to which it is to be connected. In the position of the operating lever 38 shown in Fig. 1, the bent-over ends 32 and 33 occupy the highest position and springs 12 press the functional part up against said ends 32 and 33. When the mobile unit 8 has been moved to close to the basic unit 1 as shown in Fig. 2, the operating lever 38 is pulled out from beneath the bottom part 10, whereupon the projecting part of the operating lever functioning as a foot pedal is pressed down into the position shown in Fig. 2. When this foot pedal is pressed down, the operating lever 38 tilts about pin 21, and in so doing pulls down pin 29 and the arm 31 connected thereto. Pin 28 and arm 30 are also pulled down via the levers 22 and 23 coupled by pin 26. As a result of the arms 30 and 31 being pulled down, the bent-over ends 32 and 33 of these arms press the stops 34 and 35, and hence the functional part 14, down into the position shown in Fig. 2 against the action of the springs 12. In this position roller 15 is at a level completely beneath hook 4 and hook 16 is at a level at which it fits in the recess 5. The mobile unit 8 is now driven against the basic unit with the foot pedal depressed, the roller 15 being situated directly beneath hook 4 and hook 16 engages in recess 5. If the foot pedal is then released, the mobile unit 8 comes into the connected position shown in Figs. 3 and 4, Fig. 3 showing the situation when the basic unit and the mobile unit 8 are both on the same flat floor and Fig. 4 the situation if the mobile unit 8 is at a higher level than the basic unit 1. In each connected position, the position of the bottom part of the functional part 14 is fixed horizontally and vertically with respect to the basic unit 1, since springs 12 press the roller 15 against the convex contact surface 6 of hook 4. The springs 12 will also press the functional part 14 with contact surface 18 of hook 16 against contact surface 7 of recess 5, so that the top part of the functional part 14 also occupies a fixed position with respect to the basic unit. When in the connected position both the basic unit and the mobile unit are on a flat floor, then there is a clear space between the stops 34 and 35, on the one hand, and the bent-over ends 32 and 33, on the other hand, as shown in Fig. 3. If the floor is not flat, the mobile unit at roller 15 being somewhat higher than the basic unit 1, then the distance between stop 34 and a bent-over end 32 is greater, as shown in Fig. 4. If a mobile unit 8 is at a somewhat lower level, then this distance is of course smaller. Figs. 5 to 7 show one embodiment of a connecting mechanism according to the invention in which each connecting element on the basic unit 1 is formed by a roller 40 secured to be freely rotatable on a spindle 41 extending in the direction in which the units 1 and 8 can move towards and away from one another. A roller 40 is provided near each bottom corner at the side of the basic unit 1 to which the mobile unit 8 can be connected. As considered in its axial direction, roller 40 has a semi-circular peripheral surface fitting in a convex hook 42 forming the connecting element on the functional part 14 of the mobile unit 8. Since the contact surface between the roller 40 and hook 42 is a cylindrical surface, the basic unit 1 and the functional part 14 of the mobile unit 8 are each fixed with respect to one another at the centre 43 of the cylindrical surface when the units are connected, but the functional part 14 of the mobile unit 8 has freedom to rotate with respect to a line through the centres 43 so that the units can also be positioned with respect to one another at the top in the same way as the connecting elements 5, 7 and 16, 18 shown in Figs. 1 to 4. Also, the rollers 40 shown in Figs. 5 to 7 can roll in the channel-shaped hooks 42 in order to give the units 1 and 8 some freedom of movement in a direction perpendicular to the drawing plane, and this may be important if one of the units is skew and/or is standing on a floor sloping somewhat in that direction. Figs. 5, 6 and 7 respectively show a situation in which the basic unit 1 and the mobile unit 8 are both on the same flat floor (Fig. 5), a situation in which the basic unit 1 is completely or partly on a somewhat higher floor than the mobile unit 8 (Fig. 6), and a situation in which the basic unit 1 is situated completely or partly on a somewhat lower floor than the mobile unit 8 (Fig. 7). In Figs. 5 to 7 the hook-shaped connecting element 42 is shown in solid lines in the position connected to roller 40 while the broken lines show the position disconnected from roller 40, in which position the units 1 and 8 can be moved apart or towards one another without the hook 42 coming into contact with the roller 40. In the position shown in Fig. 7, in which the basic unit is in its lowest position at the side of hook 42, the disconnected highest position of the functional part 14 of the mobile unit 8 as shown in broken lines in Fig. 7 coincides with the position in which the functional part 14 is kept pressed down during the movement of the mobile unit 8 towards or away from the basic unit 1 (the transport position shown by reference 46). In Figs. 5 and 6 this transport position 46 is at a distance beneath the broken-line position, this distance corresponding to the distance that the basic unit 1 is lower than the mobile unit 8. Figs. 8 to 11 show an embodiment for mechanically latching the connection made between the mobile unit 8 and the basic unit 1 and for establishing an electrical connection between an electrical power supply in the basic unit 1 and functions requiring an electrical power supply in the functional part 14 of the mobile unit. The above-described operating lever 38, for the purpose of mechanically connecting and disconnecting the mobile unit 8 and the basic unit 1, is used for this mechanical latching and electrical connection. To latch the mechanical connection the operating lever 38 is movable in its longitudinal direction in the bottom part 10 of the mobile unit 8. If the operating lever 38 is pressed in in the direction of arrow 50 into the bottom part 10 a screw 51 freely rotatable but axially immovable on the free end of the lever 38 operating as a foot pedal, abuts a nut 52 fixed in the bottom part 10. In this position of the operating lever 38 a projection 53 on the other end of the operating lever 38 comes against a leaf spring 54 at the end of a rod 55 axially movable in the bottom part 10. By turning screw 51 in nut 52 by hand or a hand tool when the operating lever is in this position, the operating lever moves further in the direction indicated by arrow 50 and projection 53 via leaf spring 54 presses rod 55 in the direction indicated by arrow 50, the rod 55 in turn turning an arm 59 pivotally secured to the bottom part 10 about pivot 58 from the position shown in Fig. 8 into the position shown in Fig. 9. Pin 60 fixed on arm 59 comes to lie on a projection 61 fixed on the basic unit 1, as shown in Fig. 9. In this condition pin 60 also presses against an element 63 fixed pivotally about pivot 62 on the basic unit. When said element 63 turns, a lip 64 fixed on element 63 operates an electrical switch pin 65 to establish the above mentioned electrical connection. As a result of the co-operation of pin 60 and projection 61 the coupled mobile unit 8 cannot now be readily disconnected by pressing down the functional part 14 of the mobile unit. For such disconnection the operating lever 38 must first be unscrewed from the bottom part and pulled out. Since this operation requires some time, the electrical connection has already been disconnected for some time when mechanical disconnection is effected by pressing in the foot pedal end of the operating lever 38, so that undesirable voltage build-up when the electrical connections are broken has already ceased when the mechanical disconnection is effected, and there is no burning of the contacts of the switch providing the electrical connection nor any risk of the contacts still being live if they are touched. To latch the functional part 14 of the mobile unit 8 in its pressed-down position during transport and movement of the mobile unit 8, an arm 70 is connected to pin 26 as shown in Figs. 8, 9 and 12, 13. Arm 70 is connected by a screw 71 to a block 72. When the functional part 14 is pulled down by ends 32 and 33 of arms 30 and 31 the levers 22 and 23 occupy the position shown in Fig. 2, connecting pin 26 and the block 72 connected thereto occupying their highest position. In this highest position a slide 75, loaded by spring 74 and provided with a slot 76 in which the screw 71 but not the block 72 fits, is pulled into the position shown in Fig. 12, the block 72 coming to rest on the edges of slot 76 thus preventing the springs 12 from pressing up the functional part 14. Only when the mobile unit 8 has been moved against basic unit 1 in this position shown in Fig. 2 the slide 75 is pulled into the position shown in Fig. 13 by means of cable 77 connected to a handle (not shown) on mobile unit 8, and in this position, the block 72 is free from slot 76 so that springs 12 can press up the functional part 14 of mobile unit 8 in order to make the connection between units 1 and 8.

Claims: A connecting mechanism for connecting a functional part (14) of a mobile unit (8) to a basic unit (1), comprising at least one first set of connecting elements (4, 6, 15) formed by a first connecting element (4, 6) connected to the basic unit (1) and a second connecting element (15) connected to the functional part (14) of the mobile unit (8), which second connecting element (15) can co-operate with the first connecting element (4,6) in order functionally to connect the units (1, 8) in a required position, characterised in that the mobile unit (8) comprises a mobile bottom part (10) and thereabove a functional part (14) which rests resiliently on the bottom part by means of a resilient element between (12) said parts and in that the functional part (14) of the mobile unit (8) is movable between a first position in which the second connecting element (15) is at a different level from the first connecting element (4) and the first and second connecting elements are adapted to be placed exactly above one another and a second position in which the connecting element (4) is in contact, in a contact surface (6), with the second connecting element (15) for fixing the units (1, 8) in place relatively to one another in the vertical direction and in the direction in which they are movable towards one another. A connecting mechanism according to claim 1, characterised in that during the connection of the functional part (14) of the mobile unit (8) and the basic unit (1) the resilient element (12) presses the second connecting element (15) against the first connecting element (4, 6). A connecting mechanism according to claim 2, characterised in that the contact surface (6) is situated in a convex plane. A connecting mechanism according to claim 3, characterised in that one of the connecting elements of the first set is a roller (15), the axis of rotation of which extends in the direction in which the units (1, 8) are movable towards one another. A connecting mechanism according to any one of the preceding claims, characterised in that at least a second set of connecting elements (5, 7; 16, 18) is provided which is higher than the first set of connecting elements (4, 6, 15), which second set of connecting elements (5, 7, 16, 18) is formed by a third connecting element (5, 7) connected to the basic unit (1) and a fourth connecting element (16, 18) connected to the functional part (14) of the mobile unit (8), which third (5, 7) and fourth connecting element (16, 18) in the active state form a contact surface (7, 18) with one another extending in the vertical direction. A connecting mechanism according to claim 5, characterised in that the second set of connecting elements (5, 7, 16, 18) can form, in addition to their contact surfaces (7, 18) for the positioning of the units (1, 8) in the connected state, a second contact surface (9, 19) with one another which is formed by a surface (19) on the mobile unit (8) which in the connected state is closer to the basic unit (1) than a surface (9) on the basic unit (1). A connecting mechanism according to claim 1, characterised in that at least one arm is secured to the bottom part (10) of the mobile unit (8), which arm (30, 31) is movable between a position in which a hook (32, 33) at one end of the arm (30, 31) holds the functional part (14) in its first position against the action of the resilient element (12), and a position in which the hook-shaped end (32, 33) of the arm (30, 31) is free from the functional part (14). A connecting mechanism according to claim 7, characterised in that two levers (22, 23) are provided which are pivotally secured at its centre on the bottom part (10) and each carries one of the arms (30, 31) at one end and the other ends (25, 27) together carry a common pin (26) movable between two positions in which the pin (26) is situated respectively on either side of the connecting line between the pivot axes (20, 21) of the levers (22, 23). A connecting mechanism according to claim 8, characterised in that an operating lever (38) is pivotally secured to the bottom part (10) of the mobile unit (8), which operating lever (38) can tum the levers (22, 23) about their pivot axes (20, 21) and forms, on a side of the mobile unit (8) remote from the connecting elements (15, 16, 18), a foot pedal adapted to project outside the mobile unit. A connecting mechanism according to claim 9, characterised in that the foot pedal (38) is movable between an operative position projecting beyond the mobile unit (8) and an inoperative position in which the foot pedal (38) does not project beyond the mobile unit (8). A connecting mechanism according to claim 10, characterised in that the operating lever (38) can, by means of the end (53) remote from the foot pedal, operate a latching mechanism (60, 61, 59, 58, 55, 54) for latching the first set of connecting element (4, 6, 15) against disconnection when the foot pedal is in the inoperative position. A connecting mechanism according to claim 10 or 11, characterised in that the operating lever (38) can operate a switching mechanism (55, 59, 60, 63, 62, 64) by the end (53) remote from the foot pedal in order to establish an electrical connection between the basic unit (1) and the mobile unit (8) when the foot pedal is in the inoperative position.

Inventors: SMIT HENDRIK, SMIT, HENDRIK
Applicants: OCE TECH BV, OCE-TECHNOLOGIES B.V.
Application year: 1996
Main classification: B60D1
IPC codes: B62B3, B60D1