GUIDED VEHICLE FOR THE TRANSPORT OF PALLETS

Abstract

A guided vehicle for transporting pallets moves through a rack structure in a first direction and in a second direction that is perpendicular to the first direction. The guided vehicle includes a frame provided with a first set of wheels provided for moving the frame in the first direction, and a second set of wheels provided to move the frame in the second direction, and a loading platform. In addition, driving means configured to lift the loading platform are provided, controlled by a control unit, the upwards and downwards movement of the loading platform being linkable to the upwards and downwards movement of the first plurality of wheels. The driving means includes a cam system actuated by motor means, the cam system being provided with a set of cams in such a way that the spatial position of the cams defines three operating positions.

Claims

1.-14. (canceled)

15. A guided vehicle for transporting pallets, intended to be moved along a rack structure provided with movement rails to be movable in a first direction and in a second direction that is perpendicular to the first direction, the guided vehicle comprising: a frame provided with a first plurality of wheels provided for the movement of the frame in the first direction and a second plurality of wheels provided for the movement of the frame in the second direction, a loading platform configured to support the pallets which is able to be axially lifted perpendicular to the horizontal plane, wherein driving means configured for elevating the loading platform are provided, controlled by a control unit mounted on the frame, the upwards and downwards movement of the loading platform being linked to the upwards and downwards movement of the first plurality of wheels, wherein the driving means comprise a cam system actuated by motor means, the cam system being provided with a plurality of cams in such a way that the movement of the cam is linked to the upwards and downwards movement of the loading platform, the upwards and downwards movement of the first plurality of wheels and the upwards and downwards movement of the second plurality of wheels, such that the spatial position of the cams defines three operating positions, wherein the cam system comprises two cam assemblies, each provided with an actuator rod configured to be moved upwards and downwards associated with the first plurality of wheels, two cams spaced apart from each other that act synchronously by means of a chain gear mechanism, and wherein each of the actuator rods has a contact surface provided to be in contact with the cam in at least one operating position.

16. The guided vehicle according to claim 15, wherein the gear mechanism for each cam assembly comprises gearwheels solidly coupled to a corresponding cam, in such a way that the movement of the gearwheels is transmitted by an endless chain, and at least one drive pinion associated with a drive shaft.

17. The guided vehicle according to claim 16, wherein the endless chain comprises a pair of end regions provided with a plurality of links coupled to one another and a central region provided with a tensioning means.

18. The guided vehicle according to claim 15, further comprising elastic return means that are connected to the two actuator rods and the frame.

19. The guided vehicle according to claim 18, wherein the return means comprise a plurality of helical springs located in end areas of each of the actuating rods, wherein the upper end abuts against a portion of the actuator rod while the lower end abuts against an abutment surface present in the lower portion of the frame.

20. The guided vehicle according to claim 19, further comprising a position sensor means connected to the control unit, which are configured to detect the position of the cams in the space.

21. The guided vehicle according to claim 20, wherein the sensor means comprise three fixed probes in a fixed position and a projection provided in a movable part of the gear assembly, such that, in any of their positions in space corresponding to the operating positions of the cams, the projection is aligned with one of the three probes, thus detecting the corresponding operating position.

22. The guided vehicle according to claim 15, wherein the first plurality of wheels comprises wheels that are located in two movable housings arranged on opposite sides of the frame, the wheels being detachably mounted on fixed shafts, each end of the actuator rods being solidly connected to a respective housing, in such a way that the actuator rods and the housings are moveable together.

23. The guided vehicle according to claim 22, wherein the guide means are provided for the axial movement of the housings in an upwards and downwards direction.

24. The guided vehicle according to claim 23, wherein the guide means comprise linear grooves present in vertical walls of the frame facing one another on which a corresponding rail is able to slide.

25. The guided vehicle according to claim 15, further comprising retractable guide means linked to the first plurality of wheels.

Description

BRIEF DESCRIPTION OF THE INVENTION

[0021] FIG. 1 is a perspective view of an embodiment of the vehicle according to the present invention;

[0022] FIG. 2 is a lower perspective view of the vehicle according to the invention;

[0023] FIG. 3 is an upper plan view of the vehicle shown in FIGS. 1 and 2;

[0024] FIGS. 4a and 4b are elevation views of the vehicle of the invention in a first operating position with the second plurality of wheels in operation, with the platform at the highest position thereof, wherein some parts have been omitted for illustrative purposes;

[0025] FIG. 5 is a partial elevation view of the driving means in the first operating position;

[0026] FIGS. 6a and 6b are elevation views of the vehicle of the invention in a second operating position with the platform lowered and the second plurality of wheels in operation, wherein some parts have been omitted for illustrative purposes;

[0027] FIG. 7 is a partial elevation view of the driving means in the second operating position;

[0028] FIGS. 8a and 8b are elevation views of the vehicle of the invention in a third operating position, with the plurality of wheels in operation, wherein some parts have been omitted for illustrative purposes;

[0029] FIG. 9 is a partial elevation view of the driving means in the third operating position;

[0030] FIG. 10 is a side elevation view of the vehicle, wherein some parts have been omitted;

[0031] FIG. 11 is a perspective detailed view of the area where retractable guide means are located linked to the first plurality of wheels in a retracted position;

[0032] FIG. 12 is a detailed elevation view of the retractable guide means shown in FIG. 11 in an extended position; and

[0033] FIG. 13 is an exploded perspective view of the guided transport vehicle according to the invention and with a guide rail or channel along which the guided vehicle is able to slide.

DESCRIPTION OF A PREFERRED EMBODIMENT

[0034] In view of the aforementioned figures, and in accordance with the adopted numbering, one may observe therein a preferred exemplary embodiment of the invention, which comprises the parts and elements indicated and described in detail below.

[0035] Moreover, the terms first, second, third, and the like in the description and in the claims are used to distinguish between similar elements and not necessarily to describe a sequential or chronological order. The terms may be interchanged under appropriate circumstances and the embodiments of the invention may operate in sequences other than those described or illustrated herein.

[0036] Moreover, the terms upper, lower, up, down, and the like in the description and in the claims are used for descriptive purposes and not necessarily to describe relative positions.

[0037] FIGS. 1 to 3 show an embodiment of the guided vehicle, generally indicated with the reference (1), for transporting pallets, intended to be moved along a conventional rack structure (not shown), which is provided with movement rails to be movable in a first direction and in a second direction that is perpendicular to the first direction. Thus, the guided vehicle operates on the three spatial axes (x,y,z).

[0038] The vehicle (1) comprises a box-shaped frame (2) provided with a first plurality of wheels arranged in such a way to allow for the movement of the frame (2) in the first direction, having two wheels (3) separated from one another located on each of two opposite sides. On each of the sides, one of the wheels (3) is a drive wheel that is linked to an electric motor (4) by a chain gear system (35), both electric motors (4) working synchronously, so that both drive wheels rotate at the same speed.

[0039] The frame (2) also includes a second plurality of wheels provided for the movement of the frame in the second direction which has four wheel trains (5), each formed by two wheels (50) linked together by a gear chain (6), with two wheel trains (5) located on opposite sides to one another. Two wheel trains (5) are coupled to respective electric motors (15) (see FIG. 3) which act synchronously with one another.

[0040] Thus, the first plurality of wheels is on an axis perpendicular to the second plurality of wheels described above.

[0041] A loading platform (7) is provided at the upper portion of the frame (2) configured to lift the pallets resting on the rack structure. The pallet can be axially and vertically lifted perpendicular to the horizontal plane, wherein driving means (described in greater detail below) are provided, configured for lifting the loading platform (7), controlled by a control unit mounted on the frame (2), the upwards and downwards movement of the loading platform (7) being linkable to the upwards and downwards movement of the wheels (3).

[0042] In particular reference to the driving means, the same comprise a cam system actuated by a servomotor (8) connected to the control unit, the cam system being provided with a plurality of cams (9) (in this embodiment there are four cams), in such a way that the movement of the cam is linked to the upwards and downwards movement of the loading platform (7), the upwards and downwards movement of the first plurality of wheels and the upwards and downwards movement of the second plurality of wheels, such that the spatial position of the cams (9) defines three operating positions.

[0043] These three previous operating positions correspond to a first position (FIGS. 8a-8b) in which the vehicle moves along a main aisle and the loading platform (7) is at the lowest position thereof; a second position (FIGS. 6a-6b) in which the vehicle moves along a side channel and the loading platform (7) is at the lowest position thereof; and a third position (FIGS. 4a-4b) in which the loading platform (7) is lifted for loading a pallet (not shown).

[0044] The cam system comprises two cam assemblies located on the sides of the frame (2), each of which being provided with an actuator rod (10) movable upwards and downwards associated with the first plurality of wheels, two cams (9) spaced apart from one another operating synchronously by means of a chain gear mechanism, and wherein each of the actuator rods (10) has a pair of contact surfaces (11) intended to make contact with a respective cam (9) in an operating position. Each of the actuator rods (10) is made up of an elongated profile located inside the frame that covers a large portion of the length of the side on which it is arranged, the contact surfaces (11) being defined by recessed portions.

[0045] With regards to the gear mechanism, each cam assembly comprises a gearwheel (12) rotatably fixed to the frame and solidly coupled on a parallel plane to a corresponding cam (9), in such a way that the movement of the gearwheels (12) is transmitted by an endless chain (13) and at least one drive pinion (14) associated with a spindle (16) linked to the servomotor (8), as can be seen in FIGS. 5, 7, and 9.

[0046] The spindle (16) allows the synchronised movement to be transmitted to the two cam assemblies in a compact and efficient manner, the transmission between the servomotor (8) and the spindle (16) being carried out by means of a transmission chain (37) (see FIG. 3).

[0047] It is noteworthy to mention that the endless chain (13) carries out a reciprocating motion and comprises a pair of end regions (130) provided with a plurality of links coupled to one another, and a central region provided with a tensioning element (17) made of an elastomeric material.

[0048] In addition, the driving means include elastic return or recovery means that are linked to the two actuator rods (10) and the frame (2). More specifically, said return means comprise a plurality of helical springs (18) mounted on vertical shafts located at end areas of each of the actuator rods (10), wherein the upper end abuts against a stop segment (101) fixed to the actuator rod (10) while the lower end of the helical spring (18) abuts against a stop surface (200) in the lower portion of the frame (2).

[0049] Additionally, to ensure the correct operation of the vehicle in the different operating positions, position sensor means are provided connected to the control unit, which are configured to detect the position of the cams in space, so that the control unit is aware at all times of the operative position. These sensor means comprise three fixed probes in fixed positions and a projection in a movable part of the gear assembly, such that, in any of their positions in space corresponding to the operating positions of the cams, the projection is aligned with one of the three probes, thus detecting the corresponding operating position.

[0050] Once again in reference to the first plurality of wheels, said wheels (3) are located in two movable housings (20) arranged on opposite sides and on the outer portion of the frame (2), the wheels being mounted on rotation shafts (21) which are detachably fixed to the movable housings (20). These housings (20) are formed by drawers defined by four side walls in such a way that they are superiorly and inferiorly open. Each end of the actuator rods (10) is solidly joined to a movable housing (20), by the arrangement of bolts (22), such that they guarantee that the actuator rods (10) and the movable housings (20) move together and simultaneously in an upwards or downwards direction, depending on the operating position at each moment.

[0051] To ensure an axial movement without undesirable deviations, guide means are also provided for the axial movement in an upwards and downwards direction of the movable housings with respect to the frame. These guide means comprise linear grooves (23) in vertical walls of the frame (2) facing one another, on which a corresponding rail (24) externally fixed to a side wall of the movable housing (20) is able to slide.

[0052] In order to ensure that unwanted side movements do not occur which could cause the frame (2) to rub against the guide rails of a storage facility, retractable guide means linked to the first plurality of wheels are arranged, which will be explained below and which are shown in detail in FIGS. 11 and 12.

[0053] Said retractable guide means comprise a plurality of idler cylinders (25) housed in boxes (26) situated at the corners of the frame, the idler cylinders (25) being movable upwards and downwards by means of an actuating mechanism which is linked to the housing of the first plurality of wheels, such that in an extended condition (FIG. 12), the idler cylinders (25) extend beyond the plane defined by the lowest point of the wheels that form part of the second plurality of wheels through an outlet hole (27) present on the lower portion of each box (26). Whereas in a retracted condition (FIG. 11), the lowest end of the idler cylinders (25) is located above the plane defined by the lowest point of the wheels.

[0054] As can be seen more clearly in FIGS. 11 and 12, the actuating mechanism comprises a vertically arranged rack (28) fixed to a side wall of the frame (2), wherein a gearwheel (29) is coupled in the housing which transmits its rotational movement to a linear movement of the idler cylinder (25) through a toothed region associated with the idler cylinder (25).

[0055] Also, guide wheels (32) are provided for guidance without presence of unwanted side movements of the frame (2) along the rails (30) formed by two separate and parallel profiles (see FIG. 13), when the vehicle moves by the movement of the wheel trains (5) by coming into contact with the horizontal rolling surface (31) of the rails. These guide wheels (32) are coupled by means of a shaft (36) mounted on a prolongation (33) that projects from the side wall of the frame (2) provided to make contact with a vertical segment (34) of the rail (30). These guide wheels (32) are located on the two facing sides where the wheel trains (5) are located.

[0056] The details, shapes, dimensions and other accessory elements, used to manufacture the guided vehicle of the invention, may be suitably substituted for others which do not depart from the scope defined by the claims which are included below.