Patent Publication Number: US-2015060199-A1

Title: Order pickers

Description:
This application is a National Stage completion of PCT/GB2013/000099 filed Mar. 8, 2013, which claims priority from British patent application serial no. 1204387.3 filed Mar. 12, 2012. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to improvements in and relating to Order Pickers. 
     BACKGROUND OF THE INVENTION 
     Order Pickers are industrial trucks that are used to select items which are located in stacks. Conventionally an order picker includes a cab for an operative and a pallet into which the selected items may be placed. The Order picker is driven down an aisle between two stacks, so that the operative may pick items from pallets or storage bins located in the stacks on either side of the aisle. 
     Means may be arranged for elevating the cab, so that items may be selected from pallets or bins on upto three levels. The pallet would normally rise with the cab but may also be mounted on forks for vertical movement independently of the cab. This will enable the pallet to be lowered, as items are stacked upon it. The use of independently moveable forks will also allow the pallet to be removed from the Order Picker when the order has been filled. 
     With known Order Pickers, generally the maximum to which the cab may be elevated would typically be upto three levels, say 2.8 m to 4 m. Typically stacks may extend to 7 m to 12 m. It is common practice in warehouses to store reserve items on pallets or in bins above the pallets or bins from which the items are picked. If a conventional Order Picker comes to an empty pallet or bin, then it is necessary to call on a high reach lift truck to replace the empty pallet or bin with a replacement pallet or bin located at a bulk stock location to which the Order Picker is capable of reaching. 
     SUMMARY OF THE INVENTION 
     The present invention provides an improved Order Picker which is capable of retrieving storage bins above the normal order picking levels. 
     According to one aspect of the present invention an Order Picker comprises a body section having a pair of ground engaging wheels and a first lift mechanism pivotally mounted to one end of the body section about a vertical pivot, one or more ground engaging wheels being provided on the first lift mechanism, means being provided for pivoting the first lift mechanism relative to the body section whereby the order picker may be steered, an open cab being provided on the body section whereby an operative located in the cab may have access to stacks on either side of the order picker, the cab being mounted to the body section on a second lift mechanism by which the cab may be raised and lowered with respect to the body section independently of the first lift mechanism; and a receptacle onto or into which picked items may be placed, the receptacle being mounted on the cab on the end thereof remote from the end of the body section to which the first lift mechanism is mounted. 
     With the order picker of the present invention, the first lift mechanism may be used to lift pallets or storage bins which are outside the range of the cab when elevated to its maximum height. A further advantage of the present invention is that the first lift mechanism may be used to lower a pallet or storage bin to a level at which it is accessible from the raised cab thus avoiding the need to lower the pallet or storage bin to ground level or first clear a space at a level which is accessible from the raised cab. 
     According to a preferred embodiment of the present invention, the first lift mechanism is capable of operating to heights of from 7 to 12 meters, while the second lift mechanism is capable of raising the cab to from 2.8 to 4 meters. 
     For safety considerations, the control means for, driving the order picker, pivoting the first lift mechanism relative to the body section and raising and lowering the first lift mechanism are preferably only accessible from the lowered position of the cab. 
     According to a further preferred embodiment of the invention, the receptacle is mounted with respect to the cab on a third lift mechanism, by which the receptacle may be raised and lowered with respect to the cab, to adjust the height of the receptacle as items are stacked onto or into the receptacle and to allow the receptacle to be deposited on to the ground when an order has been filled. The receptacle may, for example, be a pallet or bin. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
       The invention is now described, by way of example only, with reference to the accompanying drawings, in which: 
         FIG. 1  shows a perspective view of an order picker in accordance with the present invention; 
         FIG. 2  shows the order picker illustrated in  FIG. 1  in conventional order picker raised mode; 
         FIG. 3  shows the order picker illustrated in  FIG. 1  being used to access pallets stored above the level normally accessible to order picker in order picker mode; 
         FIG. 4  shows a perspective view of a modified order picked in accordance with the present invention; 
         FIG. 5  shows the order picker illustrated in  FIG. 4  in conventional order picker mode; 
         FIG. 6  shows the order picker illustrated in  FIG. 4  in conventional order picker raised mode; 
         FIG. 7  shows the order picker illustrated in  FIG. 4  being used to access pallets stored above the level normally accessible to order picker in order picker mode; 
         FIG. 8  shows a perspective view illustrating a further modified order picker in accordance with the present invention; 
         FIG. 9   a  illustrates the manner in which the cab is secured to the outer section of the cab raise mast of the order picker illustrated in  FIG. 8 ; 
         FIG. 9   b  illustrates the intermediate section of the cab raise mast of the order picker illustrated in  FIG. 8 ; 
         FIG. 9   c  illustrates how the inner section of the cab raise mast of the order picker illustrated in  FIG. 8  is secured to the body section; 
         FIG. 10  is a rear view of the cab raise mast of the order picker illustrated in  FIG. 8 ; 
         FIG. 11  is a view of the of the cab raise mast of the order picker body illustrated in  FIG. 8 , from above; and 
         FIG. 12  is a detailed view of the intermediate section of the cab raise mast of the order picker body illustrated in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     As illustrated in  FIGS. 1 to 3  an order picker  10  has a body section  12  having a pair of rear ground engaging wheels  14 , one wheel  14  being mounted on each side of the body section  12 , towards the rear of the body section  12 . 
     An arm  20  extends forwardly from the front of the body section  12 , a vertical pivot tube  22  being provided at the end of the arm  20  remote from the body section  12 . 
     A lift mechanism  30  has a yoke assembly  32  having an upper and lower plate members  34 ,  36  extending horizontally, a pivot pin  38  extending centrally between the plate members  34 ,  36 , the pivot pin  38  being mounted in bearings, in the pivot tube  22 . 
     A single ground engaging front wheel  40  is mounted on the yoke assembly  32 , on an axle which is parallel to the plate members  34 ,  36 . The front wheel is driven by an electric or hydraulic motor  42  and gear box  44  mounted coaxially of the wheel  40 . 
     The pivot pin  38  is non-rotatably secured with respect to the yoke assembly  32 . A gear  50  is secured to the pivot pin  38  or directly to the yoke assembly coaxially of the pivot pin  38  and is engaged by a gear  52  driven by an electric steering motor  54 . A steering control on a control module  56  mounted in a fixed position on the front end of the body section  12 , adjacent arm  20 , is used to control the electric steering motor  54 . The steering control may be used to energise the electric motor  54  in either direction, to pivot the yoke assembly  32  to one side or the other relative to the body section  12 , and thereby steer to order picker  10 . The yoke assembly  32  may be pivoted in excess of 90° to either side of the straight ahead position. 
     A telescopic lift mast  60  is mounted on the yoke assembly  32 , a pair of forks  62  extending forwardly of the lift mast, being mounted on the lift mast for movement vertically thereof. 
     Means for controlling forward and reverse movement of the order picker  10  and for controlling movement of the telescopic mast  60  and forks  62 , are also provided on the control module  56 . 
     A cab  70  is mounted on the forward end of the body section  12 , the cab  70  being mounted for vertical movement on a telescopic mast  72 . The floor  74  of the cab  70  provides a platform upon which the operative may stand. The cab  70  is open to the front and provides access to the control module  56 , when to cab  70  is in a lowered position. The cab  70  is open to each side to allow access to pallets or storage bins located in stacks on either side of the order picker  10 . A frame structure  76  extends rearwardly from to rear of the cab  70 , at a working height for supporting a pallet or other receptacle  78  onto which picked items may be placed. 
     Means for controlling telescopic mast  72  is mounted on the cab  70 , for movement with the cab  70 . 
     A battery pack  80  is provided to the rear of the body section  12 , beneath the frame structure  76  on the cab  70 , to power the various systems of the order picker. A motor and hydraulic pump (not shown) may also be provided on the body section  12 , to power hydraulic systems of the order picker  10 . 
     The order picker  10  described above may be used in conventional order picker mode to pick items from pallets or storage bins located in stacks on either side of an aisle as the order picker  10  is driven straight down the aisle. As illustrated in  FIG. 2 , the cab  70  may be raised, typically from 2.8 meters or higher, to pick items from storage pallets or bins on, for example, upto three or more levels. Picked items are placed by the operative on a pallet or other receptacle  78  supported on frame  76 . 
     Alternatively, the order picker  10  may be used, with the cab  70  at its lowermost position, as a high reach lift truck, at heights typically from 7 meters to 12 meters. The articulation of the lift mechanism  30  providing good manoeuvrability and enabling the order picker  10  in this mode to operate in narrow aisles. 
     Furthermore, as illustrated in  FIG. 3 , the order picker  10  may be used in high reach mode to lower a storage pallet of bin to a level at which it is accessible from the cab  70  in a raised position, the cab  70  then being raised and the item picked from the storage pallet or bin supported in the lift mechanism  30 . 
     In the embodiment illustrated in  FIGS. 4 to 6 , the cab  170  is mounted on lift mast  172 , towards the rear of the body section  112 . The battery pack  180  is mounted towards the front of the body section  112 . 
     A floor extension  190  extends over the battery pack  180 , the floor extension  190  being attached to the cab  170  for limited vertical movement relative there to, permitting the main floor  174  of the cab  170  to move below the floor extension  190  when it abuts the battery pack  180 , the floor extension  190  being constrained to move with the cab  170  in alignment with the main floor  174 , when the main floor  174  rises above the level of the battery pack  180 . As illustrated in  FIG. 6 , the floor extension  190  will thereby permit access to storage pallets or bins supported on the lift mechanism  30 , in similar manner to that described above with reference to  FIG. 3 , in spite of the increased distance between the cab  170  and lift mechanism  30 . 
     In place of the fixed frame  76  of the embodiment illustrated in  FIGS. 1 to 3 , in the embodiment illustrated in  FIGS. 4 to 6 , the receptacle  178  is mounted on a pair of forks, the forks being mounted on the rear of the cab  170  on lift means  192 . The receptacle  178 , for example may thereby be lowered from its initial working height, as items are stacked on the receptacle  178 , to maintain the working height. Moreover, the lift mechanism  192  may lower the forks and receptacle  178  to the ground, to unload the receptacle  178  from the order picker  10 , when an order has been filled. 
     In the embodiment illustrated in  FIGS. 8 to 12 , the lift mechanism  30  is similar to that described with reference to  FIGS. 1 to 7 . In this embodiment a cab raise mast  272  is secured to the rear of the body section  212 . The mast  272  comprises three sections, an inner section  274 , an intermediate section  276  and an outer section  278 . The sections  274 ,  276  and  278  of the mast are each formed from a pair of spaced apart I-section uprights  280  mounted parallel to one another with the front and rear flange formations  282 ,  284  of one upright of being coplanar of the corresponding front and rear flange formations  282 ,  284  of the other upright  280 . The uprights  280  of each section  274 ,  276  and  278 , are interconnected by upper and lower cross members  286 ,  288 ;  290 ,  292 ; and  294 , 296  respectively, located adjacent the top and bottom of the l-section uprights  280 . 
     The cross members,  286 ,  288  of section  274 ;  290 ,  292  of section  276 ; and  294 ,  296  of section  278 ; vary in length so that the sections  274 ,  276  and  278  may be nested in telescopic manner. The uprights  280  of inner section  274  are located within the uprights  280  of intermediate section  276 ; with the outer portions of flange formations  282  of the inner section  274  engaging in the inner channel  298  formed between flange formations  282 ,  284  of intermediate section  276  and the inner portions of flange formations  284  of intermediate section  276  engaging in the outer channel  300  formed between flange formations  282 ,  284  of inner section  274 . The uprights  280  of the intermediate section  276  are located within uprights  280  of the outer section  278 , with the outer portions of flange formations  284  of intermediate section  276  engaging in the inner channel  298  formed between flange formations  282 ,  284  of outer section  278  and the inner portions of flange formations  282  of outer section  278  engaging in the outer channel  300  formed between flange formations  282 ,  284  of intermediate section  276 . 
     Rollers  302  are attached adjacent the top of sections  274  and  276 , the rollers  302  being rotatably attached in the outer channel sections  300  defined between flanges  282  and  284  of sections  274  and  276 , for rotation about axes parallel to the plane the flange formations  282  and  284 . The rollers  302  attached to inner section  274  extend into the inner channel sections  289  defined between the flange formations  282 ,  284  and engage the flange formations  284  of intermediate section  276 . The rollers  302  attached to intermediate section  276  extend into the inner channel sections  289  defined between the flange formations  282 ,  284  of outer section  278  and engage the flange formations  282  of outer section  278 . 
     Rollers  304  are pivotally attached adjacent the bottom of sections  276  and  278 , the rollers  304  being pivotally attached in the inner channel sections  298  for rotation about axes parallel to the plane the flange formations  282  and  284 . The rollers  304  on intermediate section  276  extend into the outer channel sections  300  defined between the flange formations  282 ,  284  and engage flange formations  282  on inner section  274 . The rollers  304  on outer section  278  extend into the outer channel sections  300  defined between the flange formations  282 ,  284  and engage flange formations  284  on intermediate section  276 . 
     The rollers  302  and  304  thereby ensure that as the sections  274 ,  276  and  278  move with respect to one another, the flange formations  282  and  284  of each section  274 ,  276 ,  278  are held in sliding engagement with the corresponding flange formations  282  and  284  of the adjacent section  274 ,  276 ,  278 . 
     Cam rollers  306  are mounted to the top on both sides of the inner section  274  and intermediate section  276 , on the outside of uprights  280 ; and on both sides to the bottom of intermediate section  276  and outer section  278  on the inside of uprights  280 . The cam rollers  306  are mounted for rotation about axes perpendicular to the plane of the flange formations  282 ,  284 . The cam rollers  306  at the top of inner section  274  run against the bases of the inner channels  298  of intermediate section  276 , the cam rollers  306  at the bottom of intermediate section  276  run against the bases of the outer channel sections  300  of inner section  274 . The cam rollers  306  at the top of intermediate section  276  run against the bases of the inner channels  298  of outer section  278 , and the cam rollers  306  at the bottom of outer section  278  run against the bases of the outer channel sections  300  of intermediate section  276 . The cam rollers  306  thereby serve to prevent lateral sway of the sections  276  and  278  of the mast  272 . 
     The base of inner section  274  of the mast  272  is secured centrally to the rear of the body section  212 . 
     A hydraulic ram  310  is secured to the lower and upper cross members  286 ,  288  of the inner section  274  of the mast  272 , the ram  310  extending centrally of and parallel to the upright sections  280  of inner section  274 . A piston  312  extends from the upper end of ram  310  and is secured at its free end  314  to the upper cross member  290  of the intermediate section  276 . A pair of sprocket wheels  316  are mounted in cross member  290 , one each side of the piston  312 . The sprocket wheels  316  are mounted for rotation about an axis parallel to the plane of the flange formations  282 ,  284  of the inner section  274 . 
     A pair of chains  318  engage the sprocket wheels  314 , one end of each chain  318  being anchored to the upper cross member  286  of the inner section  274 , while the other end of each chain  318  is anchored to the lower cross member  296  of the outer section  278 . In this manner when the ram  310  is extended, intermediate section  276  will be lifted relative to inner section  274  by the piston  312 , while the outer section  278  is raised relative to the intermediate section  276  by the chains  318 . 
     A pair of plates  320  are secured to the front flange formations  282  of outer section  278 , adjacent the bottom of section  278 , the plates  320  extending outwardly of uprights  280 . A platform  322  of a cab  324  is secured to the plates  320  by hook formations  326  and bolts  328 , so that movement of outer section  278  by the ram  310  and chains  318 , will raise and lower cab  324 . 
     A carriage  330  comprises a pair of end plates  332  interconnected by upper and lower of cross members  334 . The cross members  334  span outer section  278  of the mast  272 , the end plates  332  extending in juxtaposed relationship to the outer sides of uprights  280  of outer section  278 . A pair of vertically separated rollers  336  are pivotally attached to the inner surfaces of each of the end plates  332 , the rollers extending into the outer channels  300  of outer section  278  and engaging the flange formations  282 ,  284 . 
     A pair of hydraulic rams  340  are mounted, one on either side of outer section  278  of mast  272 , outside the endplates of the carriage  330 . The rams  340  are secured to extensions  338  of plates  320  and extend parallel to uprights  280  of outer section  278 . Pistons  342  extend from the upper end of rams  340 . A sprocket wheel  344  is secured to the free end of each piston  342 , the sprocket wheels  344  being mounted for rotation about axes parallel to the plane of flange formations  282 ,  284 . Chains  346  engage the sprocket wheels  344 , one end of each chain being connected to the outer section  278  and the other end of each chains  346  being connected to the carriage  330 . The rams  340  may thus be actuated to move the carriage  330  up and down the outer section  278  of the mast  272 . 
     A pair of forks  348  are secured to the cross members  334  of carriage  330 , to support a pallet or bin onto or into which picked items may be placed. 
     The cab  324  of this embodiment is provided with a suitably geared steering mechanism, for example a steering wheel  350  and drive controls which are mounted for movement up and down, with the cab  324 . The steering mechanism  350  is connected electronically to the electric steering motor  254  which acts through a gear or corresponding mechanism  250 ,  252  to pivot the lift mechanism  30  and front wheel  40  relative to the body section  211 , to steer the order picker. The order picker  210  may thereby be steered with the cab  212  raised of lowered. 
     Various modifications may be made without departing from the invention. For example while in the above embodiments a single front wheel  40  is provided on the lift mechanism  30 , two front wheels may alternatively be provided. The or each front wheel and/or the rear wheels of the order picked may be driven. 
     The order picker may be driven, steered and the different lift mechanisms operated by means of electric motors or hydraulic mechanisms.