CA2498865C - Structure for push back pallet storage systems - Google Patents
Structure for push back pallet storage systems Download PDFInfo
- Publication number
- CA2498865C CA2498865C CA 2498865 CA2498865A CA2498865C CA 2498865 C CA2498865 C CA 2498865C CA 2498865 CA2498865 CA 2498865 CA 2498865 A CA2498865 A CA 2498865A CA 2498865 C CA2498865 C CA 2498865C
- Authority
- CA
- Canada
- Prior art keywords
- pawl
- rails
- section member
- pallet
- carriage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
- B65G1/00—Storing articles, individually or in orderly arrangement, in warehouses or magazines
- B65G1/02—Storage devices
- B65G1/026—Racks equipped with a displaceable load carrying surface to facilitate loading or unloading
Abstract
It comprises a set of side members and cross members arranged in levels inside of which pallets are fed resting on carriages that can be moved lengthways relative to fixed beams and formed from an open inverted U-shaped section member which wings include inner bearings. Said section member surrounds the fixed beams and the bearings rest by the lower portion of the flange of the beams which are formed from an open I-shaped section member. The bearings are fitted on aligned transverse shafts housed into shaped portions projecting inward of each wing of the section member of the rails so that they do not protrude from the entire width of the section member of the rail. Constructive improvements are obtained as for simplicity, economy, space saving and effectiveness in guiding of the rails moving the pallets.
Description
5'TRtX.'T~3R"E MR PUSH BACK PALLET STORAGE SYSTEMS
The present invention relates to a structure for push back pallet storage systems which novel manufacturing, conformation and design features fulfil the purpose to which it has been specifically conceived, with a maximum safety and effectiveness and providing many advantages as it will be detailed in the present specification.
More particularly, the invention refers to an improvement in depth pallet storage systems referred to as push back that allow a fast operation speed and high storage density. In these storage systems, pallets are stored placed.on a slightly inclined plane so that the last one that was introduced is the first one that is extracted.
Several levels may be arranged in height with which a simple selectivity of the stock is obtained in contrast with block stacking conventional procedures.
In conventional push back systems, a forklift truck places the pallet loads in the system on a platform that may be moved lengthwise so that each platform is pushed back by the next loadedpallet. For unloading, each platform slips forward in the rack as the previous pallet is extracted with the help of the slightly inclined plane on which said platforms are arranged. Loading and unloading of the pallets is carried out through a central passageway wherein the forklift truck moves.
The movable platforms in the conventional push back systems basically comprise a metallic frame provided with wheels or rollers. One of these structures is described in the US patent 5,312,004 which refers to a slidable platform for a push back system. The platform comprises two rails acting as a guide for rollers fitted in frames running above the rails.
Although this structure is effective, it suffers from several disadvantages such as a great constructive complexity causing, among other things, that the necessary inclination for unloading the pallets by gravity must be high.
The main object of the present invention is to provide an alternative to this type of pallet storage systems through which it is possible to overcome the above disadvantages further providing many advantages regarding them, as it will be detailed hereinafter.
According to the present invention, there is provided a structure for push back pallet storage systems comprising a set of side members and cross members arranged in several levels inside of which pallets may be fed in depth resting on carriages that can be moved lengthways relative to longitudinal beams fixed to said structure, in that said movable carriages are formed from a substantially inverted U-shaped section member provided with wings inside of which respective rotatable bearings are fitted, said section member being adapted to be arranged surrounding said longitudinal beams outwardly so that the bearings run inwardly along the lower portion of a flange of said beams, characterized in that each movable carriage is provided, at the end thereof, with a rotatable pawl having a first end extending upward and which may protrude from the upper portion of the carriage through an opening formed therein and a second, opposed end extending downward and which may be received into an opening formed in the fixed rail, and a shaft being provided transversely fitted inside the movable carriage passing through said pawl at a point of said first end nearer than said second end of the pawl, so that if no pallet is present on a pair of movable carriages, the second end of the pawl remains inserted into said opening of the fixed rail by the own weight of the pawl preventing the carriage from being moved relative to the corresponding rail, the carriage being released when a pallet rests on the first end of the pawl protruding from said upper portion of the carriage through the opening thereof.
Preferably, this structure has the feature that the rails are formed by an open, substantially inverted U-shaped section member. Respective bearings are rotatably fitted at the lower portion of the wings of the section member. It should be kept especially in mind the fact that the bearings are fitted on aligned shafts housed into shaped portions projecting inwardly of each wing of the U-shaped section member of the rails, so that said bearings do not project from the entire width of said section. This advantageously allows reducing the distance between the rails.
. Preferably, the open cross section of said movable carriages is properly adapted to be arranged for surrounding the longitudinal beams. These longitudinal beams have a substantially I-shaped cross section, so that said bearings run through the inside of the flange of said beams.
Preferably, with a structure such as that herein described a very reliable and effective pallet storage means is achieved by means of the so called push back systems. The fact of providing movable carriages obtained from a section member having a configuration "embracing" the beam involves an assurance that the rail will not work their way out of its path during. the forklift truck operation. Furthermore, since two rollers are provided for each rail, guiding is more accurate as there is less freedom of lateral movement.
Preferably, the beams of the structure are formed by an open section member obtained from a single metal sheet bent for forming said section member.
The construction of the structure of the invention is extraordinarily simplified by making this type of section members, thus reducing the costs of the assembly.
Preferably, in one embodiment, three pairs of carriages that can be moved relative to the corresponding fixed longitudinal beams are provided.
Each pair of rails is provided in such a way that the rail of each pair is arranged at a different level in height regarding the adjoining one, the pair of rails in the outer portion of the structure having the shortest height and the pair of rails in the inner portion thereof having the highest height. According to this embodiment, a structure having this *configuration allows a pallet to be stored for each pair of rails plus an additional pallet (if any) that would be placed in the last place resting on the rails.
Preferably, the invention further provides a mechanism that guarantees the locking of the assembly when there is no load on the movable carriages. In this way, each movable carriage is provided, at the end thereof, with a rotatable pawl having a first end projecting upward and which may protrude from the upper portion of the carriage through an opening formed therein. The rotatable pawl has a second, opposed end projecting downward and which may be housed into an opening formed in the corresponding fixed rail. There is also provided a transverse shaft inside the movable carriage passing through said rotatable pawl.
The transverse shaft passes through the pawl at a point in the first end thereof nearer than the second end thereof.
Preferably, according to the previously defined structure of the pawl, when no pallet is present on a pair of movable carriages, the second end of the pawl remains inserted into the opening of the fixed rail due to the own weight of the pawl. Displacement of the carriage regarding the corresponding rail is therefore prevented, locking the assembly when there. is no load.
Preferably, when a pallet rests on the pair of carriages, the pallet is arranged on the first end of the pawl that projects from of the upper portion of the carriage through said opening thereof, pushing out the second end of the pawl from the opening of the fixed rail and thus releasing the assembly so that the carriages may be moved.
Preferably, the pawl in each carriage is provided at the initial end thereof through which the pallets are fed into the structure.
Due to the provision of the rotatable pawl mechanism the pairs of movable carriages are only moved when necessary and in a synchronized way, two by two. A maximum optimisation in the load and unload process in the storage system is achieved since the proper positioning of the carriages is thus always guaranteed.
The features and the advantages of the structure for push back pallet storage systems of the present invention will be apparent from the detailed description of a preferred embodiment thereof which will be given hereinafter by way of a non limitative example, with reference to the drawings that are herein accompanied.
4a In the drawings:
Fig. 1 is a front elevational view of one level of the structure of the invention;
Fig. 2 is a side elevational view of three structures as that shown in Fig. 1, forming a push back load unit for four pallets;
Fig. 3 is a fully enlarged View of one of the rails of the structure of the invention as seen from an = ~
The present invention relates to a structure for push back pallet storage systems which novel manufacturing, conformation and design features fulfil the purpose to which it has been specifically conceived, with a maximum safety and effectiveness and providing many advantages as it will be detailed in the present specification.
More particularly, the invention refers to an improvement in depth pallet storage systems referred to as push back that allow a fast operation speed and high storage density. In these storage systems, pallets are stored placed.on a slightly inclined plane so that the last one that was introduced is the first one that is extracted.
Several levels may be arranged in height with which a simple selectivity of the stock is obtained in contrast with block stacking conventional procedures.
In conventional push back systems, a forklift truck places the pallet loads in the system on a platform that may be moved lengthwise so that each platform is pushed back by the next loadedpallet. For unloading, each platform slips forward in the rack as the previous pallet is extracted with the help of the slightly inclined plane on which said platforms are arranged. Loading and unloading of the pallets is carried out through a central passageway wherein the forklift truck moves.
The movable platforms in the conventional push back systems basically comprise a metallic frame provided with wheels or rollers. One of these structures is described in the US patent 5,312,004 which refers to a slidable platform for a push back system. The platform comprises two rails acting as a guide for rollers fitted in frames running above the rails.
Although this structure is effective, it suffers from several disadvantages such as a great constructive complexity causing, among other things, that the necessary inclination for unloading the pallets by gravity must be high.
The main object of the present invention is to provide an alternative to this type of pallet storage systems through which it is possible to overcome the above disadvantages further providing many advantages regarding them, as it will be detailed hereinafter.
According to the present invention, there is provided a structure for push back pallet storage systems comprising a set of side members and cross members arranged in several levels inside of which pallets may be fed in depth resting on carriages that can be moved lengthways relative to longitudinal beams fixed to said structure, in that said movable carriages are formed from a substantially inverted U-shaped section member provided with wings inside of which respective rotatable bearings are fitted, said section member being adapted to be arranged surrounding said longitudinal beams outwardly so that the bearings run inwardly along the lower portion of a flange of said beams, characterized in that each movable carriage is provided, at the end thereof, with a rotatable pawl having a first end extending upward and which may protrude from the upper portion of the carriage through an opening formed therein and a second, opposed end extending downward and which may be received into an opening formed in the fixed rail, and a shaft being provided transversely fitted inside the movable carriage passing through said pawl at a point of said first end nearer than said second end of the pawl, so that if no pallet is present on a pair of movable carriages, the second end of the pawl remains inserted into said opening of the fixed rail by the own weight of the pawl preventing the carriage from being moved relative to the corresponding rail, the carriage being released when a pallet rests on the first end of the pawl protruding from said upper portion of the carriage through the opening thereof.
Preferably, this structure has the feature that the rails are formed by an open, substantially inverted U-shaped section member. Respective bearings are rotatably fitted at the lower portion of the wings of the section member. It should be kept especially in mind the fact that the bearings are fitted on aligned shafts housed into shaped portions projecting inwardly of each wing of the U-shaped section member of the rails, so that said bearings do not project from the entire width of said section. This advantageously allows reducing the distance between the rails.
. Preferably, the open cross section of said movable carriages is properly adapted to be arranged for surrounding the longitudinal beams. These longitudinal beams have a substantially I-shaped cross section, so that said bearings run through the inside of the flange of said beams.
Preferably, with a structure such as that herein described a very reliable and effective pallet storage means is achieved by means of the so called push back systems. The fact of providing movable carriages obtained from a section member having a configuration "embracing" the beam involves an assurance that the rail will not work their way out of its path during. the forklift truck operation. Furthermore, since two rollers are provided for each rail, guiding is more accurate as there is less freedom of lateral movement.
Preferably, the beams of the structure are formed by an open section member obtained from a single metal sheet bent for forming said section member.
The construction of the structure of the invention is extraordinarily simplified by making this type of section members, thus reducing the costs of the assembly.
Preferably, in one embodiment, three pairs of carriages that can be moved relative to the corresponding fixed longitudinal beams are provided.
Each pair of rails is provided in such a way that the rail of each pair is arranged at a different level in height regarding the adjoining one, the pair of rails in the outer portion of the structure having the shortest height and the pair of rails in the inner portion thereof having the highest height. According to this embodiment, a structure having this *configuration allows a pallet to be stored for each pair of rails plus an additional pallet (if any) that would be placed in the last place resting on the rails.
Preferably, the invention further provides a mechanism that guarantees the locking of the assembly when there is no load on the movable carriages. In this way, each movable carriage is provided, at the end thereof, with a rotatable pawl having a first end projecting upward and which may protrude from the upper portion of the carriage through an opening formed therein. The rotatable pawl has a second, opposed end projecting downward and which may be housed into an opening formed in the corresponding fixed rail. There is also provided a transverse shaft inside the movable carriage passing through said rotatable pawl.
The transverse shaft passes through the pawl at a point in the first end thereof nearer than the second end thereof.
Preferably, according to the previously defined structure of the pawl, when no pallet is present on a pair of movable carriages, the second end of the pawl remains inserted into the opening of the fixed rail due to the own weight of the pawl. Displacement of the carriage regarding the corresponding rail is therefore prevented, locking the assembly when there. is no load.
Preferably, when a pallet rests on the pair of carriages, the pallet is arranged on the first end of the pawl that projects from of the upper portion of the carriage through said opening thereof, pushing out the second end of the pawl from the opening of the fixed rail and thus releasing the assembly so that the carriages may be moved.
Preferably, the pawl in each carriage is provided at the initial end thereof through which the pallets are fed into the structure.
Due to the provision of the rotatable pawl mechanism the pairs of movable carriages are only moved when necessary and in a synchronized way, two by two. A maximum optimisation in the load and unload process in the storage system is achieved since the proper positioning of the carriages is thus always guaranteed.
The features and the advantages of the structure for push back pallet storage systems of the present invention will be apparent from the detailed description of a preferred embodiment thereof which will be given hereinafter by way of a non limitative example, with reference to the drawings that are herein accompanied.
4a In the drawings:
Fig. 1 is a front elevational view of one level of the structure of the invention;
Fig. 2 is a side elevational view of three structures as that shown in Fig. 1, forming a push back load unit for four pallets;
Fig. 3 is a fully enlarged View of one of the rails of the structure of the invention as seen from an = ~
elevational view;
Fig. 4 is a fragmentary ei.ev-ational view of a movable carriage fitted on the corresponding fixed rail, said movable carriage being provided with a rotatable pawl in a locked position;
Fig. 5 is _a front elevational view of the movable carriage and the fixed rail in Fig. 4 in which the pawl is in the locked position;
Fig. 6 is a fragmentary elevational view of a movable carriage fitted on the corresponding fixed rail, showing the rotatable pawl in the unlocked position;
Fig. 7 is aÃront elevational view of the movable carriage and the fixed rail in Fig. 6 in which the pawl is in the unlocked position;
Fig. 8 is a fragmentary plan view showing a movable carriage fitted on the respective fixed rail of the structure of each of the three pairs forming the assembly of the embodiment shown; and Fig. 9 is a front elevational view of one level of the structure of the invention:
A detailed list of the various parts cited in the present invention is given below.
(1) side members ;
(2) cross members;
(3) upri.ght posts;
(4, 5, 6) pallets;
(7, 8, 9) movable cartiages;
(10) direction of movement of the pallets;
(11) longitudinal beams fixed to the structure;
(12, 13) wings of the section of the rails;
(14', 15) shaped portions of the section of the rails;
(16, 17) aligned transverse shafts;
(18, 19) washers;
(20, 21) bearings;
=
_ 6 ..
(22) lower portion of the web of the longitudinal beam septi.on;
(23, 24, 25) raoks of the structure;
(26) load and unload area;
(100) initial end of the carriage;
(101) initial side member;
(102) intezmediate side members;
(103) diagonal members;
(200) pawl;
(201) first end of tho pawl;
(202) second end of the pawl;
(203) transverse shaft of the pawl;
(204) upper portion of the carriage;
(205) opening of the upper portion of the carriage;
(206) head of the fixed r-ail; and (207) opening in the head Qf the fixed rail.
The invention shown by way of an example in the figures of the drawings that are herein attached in the present specification is intended to be used to the variant of the known compact palletisation referred to as push back. The structure comprises a set of side members (1), cross members (2) and upright posts (3).
In the figures only one load level has been depicted defined by the plane of the cross members (2) but it will be understood that there may exist as many levels as required by the storage.
The pallets (4, 5, 6) are fed in depth resting on corresponding pairs of movable carriages (7, 8, 9) as shown in the elevational view in fig. 1. The pairs of movable carriages (7, 8, 9) may be moved in the load and unload direction as shown by the arrow (10) in Fig. 2 relative to longitudinal beams =(11) fixedly fitted in the structure and which may be seen in Fig. 1. The longitudinal beams (11) rest by their own weight on the cross members (2) of the structure and their ends are fixed thereto by means of screws or any appropriate means.
As it can be seen from the view in Fig. 2, the pairs of movable carriages (7, 8, 9) are provided in such a way that they are slightly inclined lengthwise (of the order of 10) for promoting unloading operations with a forklift truck.
The movable carriages (7, 8, 9) are formed from a open, substantially inverted U-shaped section member. Each of the wings (12, 13) of the section member has a shaped portion (14, 15) projecting inwardly of the U-shaped section member. A transverse shaft (16, 17) is provided in each shaped portion (14, 15) . Each shaft (16, 17) holds, by means of washers (18, 19) fitted therein, respective 15. bearings (20, 21) which may be rotated freely during the rail displacement (7, 8, 9) . Therefore, said bearings (20, 21) rest on the lower portion (22) of the web of the beam section (11) . In said Fig. 3, it may be appreciated how a washer (18, 19) is provided inside the section member and another one in the outer portion thereof to retain the bearing (20, 21) axially. The assembly of the bearings (20, 21) is such that these and the corresponding shaft (16, 17) do not protrude from the entire width of the section member of the rail (7, 8, 9) due to the shaped portions (14, 15), and therefore the distance between the rails (7, 8, 9) is notably decreased. It should be pointed out that, although in the embodiment of the figures axialretention means of the bearings comprising washers (18, 19) fitted in the shafts (16, 17) have been used, other alternative means such as threaded shaft and nut by the outer portion would be also possible.
The open section member of the rails (7, 8, 9) surrounds the longitudinal beam outwardly (11) of the structure and therefore a perfect guiding of the assembly is achieved as well as a remarkable movement accuracy. This -8~
is achieved by folding said section member until conferring it a substantially I-shaped section member, as it may be seen from Fig. 3.
Side members (1), cross members (2) and upright posts (3) of the structure of the push back system of the present invention define sets of racks (23, 24, 25) forming inner load passageways with several levels, according to the necessities and the height of the premises. In each level of the structure a product reference may be provided as they are each independent since it is not necessary to drive the f orkl i f t truck into the passageways.
The forklift trucks run along the approach passageway perpendicular to the load passageways (not shown). In order to be positioned, the forklift trucks are guided toward the passageway and to the given height required by the product in the pallet (4, 5, 6) to be placed at every time.
In the embodiment shown in the figures, the pallet (4) rests on the pair of rails (9) whereas, in a similar way, the second pallet (5) rests on the intermediate pair of rails (8) and the third pallet (6) do it on the pair of rails (7). A fourth pallet could be placed resting on the rails of the structure.
The longitudinal beams (11) provided on the cross members (2) of the structure are separated according to the width required by each pallet (4, 5, 6) for ,achieving a stable support. The length of each rail (7, 8, 9) running along the corresponding beam (11) is the same as the depth of the pallet (4, 5, 6).
:.Along each rail (7, 8, 9) there are provided as many bearings (20, 21) as necessary, generally one at each side in the two ends of each rail (7, 8, 9) If more bearings ,(20, 21) are requir:ed depending on the load to be supported, more bearings may be provided, these being perfectly guided in their path.
With a structure as the one herein described it is not necessary the forklift truck to be driven inside the passageway as it is always placed at the beginning of the passageway above its corresponding level.
In use, the operator feeds the first pallet (6) on the pair of rails (9) as it is at a level slightly higher than the next one, as it can be seen from Fig. 1.
The pallet (6) only rests on said pair of rails (9). Once the pallet (6) has been placed, the operator places the second pallet (5) displacing with this the first pallet (6) inward of the structure in the direction of the arrow (10) in Fig. 2 of the drawings. The pallet (6) is moved sl ight ly raised so that it does not touch the parts of the structure due to the level of the rails (9). When the first pallet (6) hasbeen travelled a distance equal to the space that it takes up [which is occupied by the second pallet (5)), it is lowered until resting on the immed%ately shorter height rails (8). The third pallet (4) is moved and it is positioned in the same way as the second pallet (5) and 2.0 since the first pallet (6) and. the second pallet (5) have been moved inward of the structure, the third pallet (4) is lowered and rests on the pair of shorter height rails (7).
As it has been previously noted, a fourth pallet (not shown) may be provided resting on all of the rails (7, 8, 9).
To extract the three pallets (4, 5, 6) shown plus the fourth pallet of the structure, not shown, the operator first extracts the last pallet which was fed, the three remaining pallets (4, 5, 6) being inside the passageway, returning back to the load and unload area (26) tnoving above the rails (7, 8, 9) due to the longitudinal inclination, thereof that makes them to be returned back to said load and unload area (26) of the pallets.
The movable carriages (7, 8, 9) are always braked since the cross member (2) provi+ded at the beginning of the CA 02498865 . 2005-02-28 passageway acts as a etop member. When removing the second pallet (4) the process is repeated by lowering other two pallets (5, 6) and so forth. In the loading operation, the movement of the pallets is carried out by pushing inward of the passageway and upwards, while in the unloading operation this is performed outward of the passageway and downwards slipping the pallets by gravity.
A further embodiment of the invention is now disclosed with reference to Figs. 4 to 9. In this embodiment, the push back cc-mpact palletisation system comprises the already, ddisclosed structure, formed by a frame including upright posts or props (3), an initial side member (101) and intermediate side members (102), as shown in Fig. 9, The frame of the structure is further provided with diagonal rtnembers (103).
The loaded pallets (4, 5, 6) are fe:d in depth supported on pairs of movable carriages (7). The movable carriages (7) may be moved in the loading and unloading direction relative to the longitudinal rails (11) fixedly fitted in the structure. The longitudinal rails (11) rest by their own weight on the side members (101, 102) of the structure and their ends are fixed thereto by means of screws or any appropriate means.
As it can be seen from the view in Fig. 9, the rails. (11) have a small longitudinal inclination (of the order of 4%) for promoting unloading operations with the forklift truck.
Each of the movable carriages (7) of the structure has, in the initial end (100) therecif, that is, in the end corresponding to the load and unload area, a rotatable pawl (200) . Said rotatable pawl (20Q) is a flat metal piece having a first end (201) extending upwards and a second end (202) extending downwards, as it can be seen from Figs. 4 and 5 of the drawings attached iri the present specification.
The rotatable pawl (200) is rotatably pivoted by means of a transverse shaft (203) placed inside the movable carriage (7), as shown in Figs. 6 and 7.
In the upper portion (204) of the movable carriage (7) where the load pallet (4, 5, 6) rests an opening (205) is formed wherein said first end (201) of the rotatable pawl (200) projects.
In the head (206) of the fixed rail (11) an opening (207) is provided for receiving the second end (202) of the rotatable pawl (200).
As it can be seen from Figs. 4 and 7, the transverse shaft (203) passes through the pawl (200) at a point of the first end (201) nearer than the second end (202) of the pawl (200). Therefore, when no pallet (4, 5, 6) is on the upper part (204) of a pair of movable carriages (7), the locked position shown in Figs. 4 and 5 occurs. In this locked position, the movable carriage (7) can not be moved relative to the fixed rail (11) as the second end (202) of the rotatable pawl (200) remains inserted into the opening (207) of the head (207) of the fixed rail (11) due to the own weight of that part of the pawl (200).
When a pallet (4, 5, 6) is placed on the. upper portion (204) of a pair of carriages (7), the lower portion of the pallet (4, 5, 6) rests on said first end (201) of the pawl (200) that projected therefrom through the opening (205) . As the pallet (4, 5, 6) rests on the first end (201) of the pawl (200) rotation thereof around the shaft (203) takes place as well as the subsequent releasing of the second end (202) of the opening (207) of the rail (11) , so that the carriage (7) may be already.moved freely relative to the rail (11).
With this pawl mechanism unwanted advance of the carriages (7) is avoided, thua assuring the locking of the assembly when no load is present on said movable carriages (7).
Therefore, it is started from an unloaded, locked position as shown in Fig. 4 in which the operator may load a first pallet (6) on a pair of carriages (7) located at a slightly upper level than the next one. The pallet (6), resting only on a pair of carriages (7), is placed on.said carriage (7) unlocking the assembly according to Figs. 6 and 7 of the drawings. The operator carries out the same operation with the other pallets, that is, a second pallet (5) is placed moving with this the first.pallet (6) inward of the structure as shown in Fig. 9 of the drawings. The pallet (6) is moved slightly raised so that it does not touch the parts of the structure due to the level of the carriages (7). When the first pallet (6) has travelled a distance equal to the space taken up [which is occupied by the second pallet (5)], it is lowered until resting on the immediately shorter height carriages (7). The third pallet (4) is moved and it is positioned in the same way as the second pallet (5) and, as the first pallet (6) and the second pallet (5) have been moved inward of the structure, said third pallet (4) is lowered and rests on the pair of shorter height carriages (7). As it has been previously noted, a fourth pallet (not shown) may be provided resting on all of the rails (11Y.
To extract the three pallets shown (4, 5, 6) plus a fourth additional pallet, not shown, from the structure, the operator first extracts the last pallet which was fed, the three remaining pallets (4, 5, 6) being inside the passageway, returning back to the load and unload area moving above the rails (11) thanks to the longitudinal inclination thereof that makes them to be returned back to said load and unload area of the pallets.
The movable carriages (7) are always braked since the side member (101) provided in the initial part of the passageway acts as a stop member. When removing the second pallet (4) the process is repeated lowering the other two pallets (5, 6) and so forth. In the loading operation, the movement of the pallets is carried out by pushing inward of the passageway and upward, whereas in the unloading operation it is performed, outward of the passageway and downward slipping the pallets by gravity.
Once having been sufficiently described what the structure for push back pallet storage systems of the present invention consists according to the enclosed drawings, it is understood that any detail modification can be introduced as appropriate, unless variations may alter the essence of the invention as summarised in the appended c 1 aimas .
Fig. 4 is a fragmentary ei.ev-ational view of a movable carriage fitted on the corresponding fixed rail, said movable carriage being provided with a rotatable pawl in a locked position;
Fig. 5 is _a front elevational view of the movable carriage and the fixed rail in Fig. 4 in which the pawl is in the locked position;
Fig. 6 is a fragmentary elevational view of a movable carriage fitted on the corresponding fixed rail, showing the rotatable pawl in the unlocked position;
Fig. 7 is aÃront elevational view of the movable carriage and the fixed rail in Fig. 6 in which the pawl is in the unlocked position;
Fig. 8 is a fragmentary plan view showing a movable carriage fitted on the respective fixed rail of the structure of each of the three pairs forming the assembly of the embodiment shown; and Fig. 9 is a front elevational view of one level of the structure of the invention:
A detailed list of the various parts cited in the present invention is given below.
(1) side members ;
(2) cross members;
(3) upri.ght posts;
(4, 5, 6) pallets;
(7, 8, 9) movable cartiages;
(10) direction of movement of the pallets;
(11) longitudinal beams fixed to the structure;
(12, 13) wings of the section of the rails;
(14', 15) shaped portions of the section of the rails;
(16, 17) aligned transverse shafts;
(18, 19) washers;
(20, 21) bearings;
=
_ 6 ..
(22) lower portion of the web of the longitudinal beam septi.on;
(23, 24, 25) raoks of the structure;
(26) load and unload area;
(100) initial end of the carriage;
(101) initial side member;
(102) intezmediate side members;
(103) diagonal members;
(200) pawl;
(201) first end of tho pawl;
(202) second end of the pawl;
(203) transverse shaft of the pawl;
(204) upper portion of the carriage;
(205) opening of the upper portion of the carriage;
(206) head of the fixed r-ail; and (207) opening in the head Qf the fixed rail.
The invention shown by way of an example in the figures of the drawings that are herein attached in the present specification is intended to be used to the variant of the known compact palletisation referred to as push back. The structure comprises a set of side members (1), cross members (2) and upright posts (3).
In the figures only one load level has been depicted defined by the plane of the cross members (2) but it will be understood that there may exist as many levels as required by the storage.
The pallets (4, 5, 6) are fed in depth resting on corresponding pairs of movable carriages (7, 8, 9) as shown in the elevational view in fig. 1. The pairs of movable carriages (7, 8, 9) may be moved in the load and unload direction as shown by the arrow (10) in Fig. 2 relative to longitudinal beams =(11) fixedly fitted in the structure and which may be seen in Fig. 1. The longitudinal beams (11) rest by their own weight on the cross members (2) of the structure and their ends are fixed thereto by means of screws or any appropriate means.
As it can be seen from the view in Fig. 2, the pairs of movable carriages (7, 8, 9) are provided in such a way that they are slightly inclined lengthwise (of the order of 10) for promoting unloading operations with a forklift truck.
The movable carriages (7, 8, 9) are formed from a open, substantially inverted U-shaped section member. Each of the wings (12, 13) of the section member has a shaped portion (14, 15) projecting inwardly of the U-shaped section member. A transverse shaft (16, 17) is provided in each shaped portion (14, 15) . Each shaft (16, 17) holds, by means of washers (18, 19) fitted therein, respective 15. bearings (20, 21) which may be rotated freely during the rail displacement (7, 8, 9) . Therefore, said bearings (20, 21) rest on the lower portion (22) of the web of the beam section (11) . In said Fig. 3, it may be appreciated how a washer (18, 19) is provided inside the section member and another one in the outer portion thereof to retain the bearing (20, 21) axially. The assembly of the bearings (20, 21) is such that these and the corresponding shaft (16, 17) do not protrude from the entire width of the section member of the rail (7, 8, 9) due to the shaped portions (14, 15), and therefore the distance between the rails (7, 8, 9) is notably decreased. It should be pointed out that, although in the embodiment of the figures axialretention means of the bearings comprising washers (18, 19) fitted in the shafts (16, 17) have been used, other alternative means such as threaded shaft and nut by the outer portion would be also possible.
The open section member of the rails (7, 8, 9) surrounds the longitudinal beam outwardly (11) of the structure and therefore a perfect guiding of the assembly is achieved as well as a remarkable movement accuracy. This -8~
is achieved by folding said section member until conferring it a substantially I-shaped section member, as it may be seen from Fig. 3.
Side members (1), cross members (2) and upright posts (3) of the structure of the push back system of the present invention define sets of racks (23, 24, 25) forming inner load passageways with several levels, according to the necessities and the height of the premises. In each level of the structure a product reference may be provided as they are each independent since it is not necessary to drive the f orkl i f t truck into the passageways.
The forklift trucks run along the approach passageway perpendicular to the load passageways (not shown). In order to be positioned, the forklift trucks are guided toward the passageway and to the given height required by the product in the pallet (4, 5, 6) to be placed at every time.
In the embodiment shown in the figures, the pallet (4) rests on the pair of rails (9) whereas, in a similar way, the second pallet (5) rests on the intermediate pair of rails (8) and the third pallet (6) do it on the pair of rails (7). A fourth pallet could be placed resting on the rails of the structure.
The longitudinal beams (11) provided on the cross members (2) of the structure are separated according to the width required by each pallet (4, 5, 6) for ,achieving a stable support. The length of each rail (7, 8, 9) running along the corresponding beam (11) is the same as the depth of the pallet (4, 5, 6).
:.Along each rail (7, 8, 9) there are provided as many bearings (20, 21) as necessary, generally one at each side in the two ends of each rail (7, 8, 9) If more bearings ,(20, 21) are requir:ed depending on the load to be supported, more bearings may be provided, these being perfectly guided in their path.
With a structure as the one herein described it is not necessary the forklift truck to be driven inside the passageway as it is always placed at the beginning of the passageway above its corresponding level.
In use, the operator feeds the first pallet (6) on the pair of rails (9) as it is at a level slightly higher than the next one, as it can be seen from Fig. 1.
The pallet (6) only rests on said pair of rails (9). Once the pallet (6) has been placed, the operator places the second pallet (5) displacing with this the first pallet (6) inward of the structure in the direction of the arrow (10) in Fig. 2 of the drawings. The pallet (6) is moved sl ight ly raised so that it does not touch the parts of the structure due to the level of the rails (9). When the first pallet (6) hasbeen travelled a distance equal to the space that it takes up [which is occupied by the second pallet (5)), it is lowered until resting on the immed%ately shorter height rails (8). The third pallet (4) is moved and it is positioned in the same way as the second pallet (5) and 2.0 since the first pallet (6) and. the second pallet (5) have been moved inward of the structure, the third pallet (4) is lowered and rests on the pair of shorter height rails (7).
As it has been previously noted, a fourth pallet (not shown) may be provided resting on all of the rails (7, 8, 9).
To extract the three pallets (4, 5, 6) shown plus the fourth pallet of the structure, not shown, the operator first extracts the last pallet which was fed, the three remaining pallets (4, 5, 6) being inside the passageway, returning back to the load and unload area (26) tnoving above the rails (7, 8, 9) due to the longitudinal inclination, thereof that makes them to be returned back to said load and unload area (26) of the pallets.
The movable carriages (7, 8, 9) are always braked since the cross member (2) provi+ded at the beginning of the CA 02498865 . 2005-02-28 passageway acts as a etop member. When removing the second pallet (4) the process is repeated by lowering other two pallets (5, 6) and so forth. In the loading operation, the movement of the pallets is carried out by pushing inward of the passageway and upwards, while in the unloading operation this is performed outward of the passageway and downwards slipping the pallets by gravity.
A further embodiment of the invention is now disclosed with reference to Figs. 4 to 9. In this embodiment, the push back cc-mpact palletisation system comprises the already, ddisclosed structure, formed by a frame including upright posts or props (3), an initial side member (101) and intermediate side members (102), as shown in Fig. 9, The frame of the structure is further provided with diagonal rtnembers (103).
The loaded pallets (4, 5, 6) are fe:d in depth supported on pairs of movable carriages (7). The movable carriages (7) may be moved in the loading and unloading direction relative to the longitudinal rails (11) fixedly fitted in the structure. The longitudinal rails (11) rest by their own weight on the side members (101, 102) of the structure and their ends are fixed thereto by means of screws or any appropriate means.
As it can be seen from the view in Fig. 9, the rails. (11) have a small longitudinal inclination (of the order of 4%) for promoting unloading operations with the forklift truck.
Each of the movable carriages (7) of the structure has, in the initial end (100) therecif, that is, in the end corresponding to the load and unload area, a rotatable pawl (200) . Said rotatable pawl (20Q) is a flat metal piece having a first end (201) extending upwards and a second end (202) extending downwards, as it can be seen from Figs. 4 and 5 of the drawings attached iri the present specification.
The rotatable pawl (200) is rotatably pivoted by means of a transverse shaft (203) placed inside the movable carriage (7), as shown in Figs. 6 and 7.
In the upper portion (204) of the movable carriage (7) where the load pallet (4, 5, 6) rests an opening (205) is formed wherein said first end (201) of the rotatable pawl (200) projects.
In the head (206) of the fixed rail (11) an opening (207) is provided for receiving the second end (202) of the rotatable pawl (200).
As it can be seen from Figs. 4 and 7, the transverse shaft (203) passes through the pawl (200) at a point of the first end (201) nearer than the second end (202) of the pawl (200). Therefore, when no pallet (4, 5, 6) is on the upper part (204) of a pair of movable carriages (7), the locked position shown in Figs. 4 and 5 occurs. In this locked position, the movable carriage (7) can not be moved relative to the fixed rail (11) as the second end (202) of the rotatable pawl (200) remains inserted into the opening (207) of the head (207) of the fixed rail (11) due to the own weight of that part of the pawl (200).
When a pallet (4, 5, 6) is placed on the. upper portion (204) of a pair of carriages (7), the lower portion of the pallet (4, 5, 6) rests on said first end (201) of the pawl (200) that projected therefrom through the opening (205) . As the pallet (4, 5, 6) rests on the first end (201) of the pawl (200) rotation thereof around the shaft (203) takes place as well as the subsequent releasing of the second end (202) of the opening (207) of the rail (11) , so that the carriage (7) may be already.moved freely relative to the rail (11).
With this pawl mechanism unwanted advance of the carriages (7) is avoided, thua assuring the locking of the assembly when no load is present on said movable carriages (7).
Therefore, it is started from an unloaded, locked position as shown in Fig. 4 in which the operator may load a first pallet (6) on a pair of carriages (7) located at a slightly upper level than the next one. The pallet (6), resting only on a pair of carriages (7), is placed on.said carriage (7) unlocking the assembly according to Figs. 6 and 7 of the drawings. The operator carries out the same operation with the other pallets, that is, a second pallet (5) is placed moving with this the first.pallet (6) inward of the structure as shown in Fig. 9 of the drawings. The pallet (6) is moved slightly raised so that it does not touch the parts of the structure due to the level of the carriages (7). When the first pallet (6) has travelled a distance equal to the space taken up [which is occupied by the second pallet (5)], it is lowered until resting on the immediately shorter height carriages (7). The third pallet (4) is moved and it is positioned in the same way as the second pallet (5) and, as the first pallet (6) and the second pallet (5) have been moved inward of the structure, said third pallet (4) is lowered and rests on the pair of shorter height carriages (7). As it has been previously noted, a fourth pallet (not shown) may be provided resting on all of the rails (11Y.
To extract the three pallets shown (4, 5, 6) plus a fourth additional pallet, not shown, from the structure, the operator first extracts the last pallet which was fed, the three remaining pallets (4, 5, 6) being inside the passageway, returning back to the load and unload area moving above the rails (11) thanks to the longitudinal inclination thereof that makes them to be returned back to said load and unload area of the pallets.
The movable carriages (7) are always braked since the side member (101) provided in the initial part of the passageway acts as a stop member. When removing the second pallet (4) the process is repeated lowering the other two pallets (5, 6) and so forth. In the loading operation, the movement of the pallets is carried out by pushing inward of the passageway and upward, whereas in the unloading operation it is performed, outward of the passageway and downward slipping the pallets by gravity.
Once having been sufficiently described what the structure for push back pallet storage systems of the present invention consists according to the enclosed drawings, it is understood that any detail modification can be introduced as appropriate, unless variations may alter the essence of the invention as summarised in the appended c 1 aimas .
Claims (5)
1. Structure for push back pallet storage systems comprising a set of side members (1) and cross members (2) arranged in several levels inside of which pallets (4, 5, 6) may be fed in depth resting on carriages (7, 8, 9) that can be moved lengthways relative to longitudinal beams (11) fixed to said structure, in that said movable carriages (7, 8, 9) are formed from a substantially inverted U-shaped section member provided with wings (12, 13) inside of which respective rotatable bearings (20, 21) are fitted, said section member being adapted to be arranged surrounding said longitudinal beams (11) outwardly so that the bearings (20, 21) run inwardly along the lower portion (23) of a flange of said beams (11), characterized in that each movable carriage (7) is provided, at the end thereof, with a rotatable pawl (200) having a first end (201) extending upward and which may protrude from the upper portion (204) of the carriage (7) through an opening (205) formed therein and a second, opposed end (202) extending downward and which may be received into an opening (207) formed in the fixed rail (11), and a shaft (203) being provided transversely fitted inside the movable carriage (7) passing through said pawl (200) at a point of said first end (201) nearer than said second end (202) of the pawl (200), so that if no pallet (4, 5, 6) is present on a pair of movable carriages (7), the second end (202) of the pawl (200) remains inserted into said opening (207) of the fixed rail (11) by the own weight of the pawl (200) preventing the carriage (7) from being moved relative to the corresponding rail (11), the carriage (7) being released when a pallet (4, 5, 6) rests on the first end (201) of the pawl (200) protruding from said upper portion (204) of the carriage (7) through the opening (205) thereof.
2. Structure for push back pallet storage system as claimed in claim 1, characterized in that said longitudinal beams (11) of the structure are formed by an open section member obtained from a single metal sheet bent to form said section member.
3. Structure for push back pallet storage systems as claimed in claim 1, characterized in that it comprises three pairs of rails (7, 8, 9) that can be moved relative to the corresponding fixed longitudinal beams (11), each of said pair of rails (7, 8, 9) being arranged such that the rail of each pair is placed at a level of height different from the adjoining one, the pair of rails (7) provided in the outer portion of the structure having the shortest height and the pair of rails (9) provided in the inner portion thereof having the highest height.
4. Structure for push back pallet storage systems as claimed in claim 1, characterized in that said bearings (20, 21) are fitted on aligned transverse shafts (16, 17) housed in shaped portions (14, 15) projecting inward of each wing (12, 13) of said U-shaped section member of the rails (7, 8, 9) so that said bearings (20, 21) do not protrude from the entire width of the section member of the rail (7, 8, 9).
5. Structure for push back pallet storage systems as claimed in claim1, characterized in that the pawl (200) is provided at the initial end (100) of each carriage (7) where the pallets (4, 5, 6) are fed into the structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2498865 CA2498865C (en) | 2005-02-28 | 2005-02-28 | Structure for push back pallet storage systems |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2498865 CA2498865C (en) | 2005-02-28 | 2005-02-28 | Structure for push back pallet storage systems |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2498865A1 CA2498865A1 (en) | 2006-08-28 |
| CA2498865C true CA2498865C (en) | 2009-08-18 |
Family
ID=36938925
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2498865 Expired - Fee Related CA2498865C (en) | 2005-02-28 | 2005-02-28 | Structure for push back pallet storage systems |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2498865C (en) |
-
2005
- 2005-02-28 CA CA 2498865 patent/CA2498865C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2498865A1 (en) | 2006-08-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4715765A (en) | Gravity flow storage system | |
| WO2005087648A1 (en) | Computer-controlled transport device | |
| CA2967012C (en) | Lifting device for palletized goods | |
| JPS60183409A (en) | Storage rack with compartment with plurality of rail and interlocking trolley | |
| EP3475212B1 (en) | High-bay warehouse with storage-and-retrieval units provided therein for storing and retrieving, or transferring, articles | |
| US7214024B2 (en) | Push back pallet storage system | |
| EP1478584B1 (en) | Storage retrieval system comprising a load receiving element | |
| AT522434A4 (en) | Shelf storage system with improved transport vehicle lifting device | |
| US5460475A (en) | Long reach shuttle for storage and retrieval machine | |
| MXPA04010361A (en) | Pushback cart storage system. | |
| EP2746193B1 (en) | Vehicle for a warehouse, stacker crane, warehouse and corresponding method | |
| EP1882648B1 (en) | Method for storing and retrieving goods, in particular drinks crates and storage system therefor | |
| CA2498865C (en) | Structure for push back pallet storage systems | |
| DE2406753C2 (en) | Transport trolleys for pallets | |
| EP2158143B1 (en) | Storage and retrieval unit for storing and retrieving, and order-picking, articles, and storage system having at least one such storage and retrieval unit | |
| WO1983002933A1 (en) | Installation for storing and displacing pallets | |
| DE3907623A1 (en) | HIGH SHELVING SYSTEM WITH A SHELVING CONVEYOR | |
| US11760585B2 (en) | Momentum arresting ramp | |
| EP0508404A1 (en) | Security device for a transport frame | |
| JP3595644B2 (en) | Article storage device | |
| MXPA05002813A (en) | Structure for push back pallet storage systems. | |
| JP4586143B2 (en) | loader | |
| JP3153898B2 (en) | Pushback storage trolley device | |
| EP1484278B1 (en) | Device, stacker crane and shelf storage for moving pallets in and out of storage | |
| DE202004017634U1 (en) | Transport and storage frame for goods trolleys has the trolleys rolled onto support rails and secured by adjustable posts and straps |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |