Abstract:
A feeder for orienting and aligning disorderly incoming articles includes a table having a peripheral wall, a rotary surface surrounded by the peripheral wall, and a discharge substantially tangential to the peripheral wall, the discharge being sized to receive one article at a time from the rotary surface in a predetermined orientation; and at least one pile eliminating member extending above the rotary surface and defining a gap with the rotary surface, the gap being sized to solely permit passage of non-superposed articles laying in the predetermined orientation on the rotary surface. It also relates to a method for doing same and a method and an apparatus for removing obstructing blocks from the discharge.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is related to U.S. patent application Ser. No. 11/117,368 filed on Apr. 29, 2005. 
     BACKGROUND OF THE INVENTION 
     1) Field of the Invention 
     The invention relates to a feeder for orienting items from a disorderly block supply and, more particularly, it relates to a feeder having a rotary table and an apparatus for breaking up superposition of items on the rotary table and mechanisms for unjamming the block discharge. 
     2) Description of the Prior Art 
     Rotary disk feeders are commonly used for orienting and aligning items from a disorderly bulk supply, mainly in the food industry (See for instance U.S. Pat. No. 3,224,554; U.S. Pat. No. 5,044,487; and U.S. Pat. No. 5,065,852). Typically they include a disk turning about its axis and are designed to receive the product to be aligned in bulk. The rotary disk is surrounded by a peripheral wall which has a discharge aperture substantially tangential to the peripheral wall. The items oriented and aligned are discharged through the discharge aperture in a single file. 
     These rotary tables perform well for uniformly sized and mostly short and uniform length items. However, the performance of these rotary tables with blocks having different lengths and/or with relative long items are often inadequate. Several problems typically occur such as blocks wedging at the discharge because the items are pilled on top of each other or are not tangent to the peripheral wall. 
     These problems often occur in the wood industries where wood blocks need to be aligned and oriented for feeding wood working machines such as finger jointers or scanning equipment, for instance. 
     Some methods have been tried to prevent the obstruction such as wipers or deflectors to wipe off any portion of the items that exceeds the thickness of the items being processed. However, these methods are inefficient for long items and items having a length dispersion, i.e. having non-uniform or random lengths. 
     Moreover, for some applications, it is desirable to have a predetermined spacing between two consecutive aligned and oriented blocks. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a feeder for aligning and orienting while reducing the obstruction of the discharge aperture of the feeder. 
     It is another object of the invention to provide a feeder having at least one automated method for dislodging obstructing blocks from the discharge aperture of the feeder. 
     It is a further object of the invention to provide a feeder in combination with a block spacer adapted to feed items with a spacing between two consecutive blocks and/or at a predetermined rate. 
     One object of the invention provides a feeder for orienting and aligning disorderly incoming articles. The feeder comprises: a table having a peripheral wall, a rotary surface surrounded by the peripheral wall, and a discharge substantially tangential to the peripheral wall, the discharge being sized to receive one article at a time from the rotary surface in a predetermined orientation; and at least one pile eliminating member extending above the rotary surface and defining a gap therewith, the gap being sized to solely permit passage of non-superposed articles laying in the predetermined orientation on the rotary surface. The pile eliminating member can be a longitudinal brush conveyor with bristles extending above the rotary surface, having a rotation axis substantially parallel to the rotary surface, and being rotatable in a direction bringing the articles towards the center of the rotary surface, away from the peripheral wall. 
     Another object of the invention provides a method for orienting and aligning disorderly incoming articles. The method comprises: feeding a rotary surface with the articles; driving the rotary surface to carry the articles to a discharge aperture defined in a peripheral wall surrounding the rotary surface, the discharge aperture being configured to only permit passage of one properly oriented article at a time; eliminating article piles or superposition on the rotary surface proximate to the peripheral wall; and individually withdrawing properly oriented articles from the rotary surface through the discharge aperture. 
     Another object of the invention provides a feeder for aligning and orienting disorderly incoming items. The feeder comprises: a table having a peripheral wall, a rotary surface surrounded by the peripheral wall, and a discharge substantially tangential to the peripheral wall, the discharge being sized to receive one item at a time and in a predetermined orientation; and at least one a dislodging arm disposed proximate to the discharge, the dislodging arm being movable between a retracted position and an extended position, the dislodging arm, when deployed to the extended position thereof, dislodging obstructing items from the discharge and pushing the items towards the center of the rotary surface, away from the discharge, thereby permitting oriented items to be received in the discharge to be withdrawn from the table. 
     Another object of the invention provides a method for orienting and aligning disorderly incoming items, comprising: feeding a rotary surface having a first rotation direction with the items; driving the rotary surface in rotation; aligning the items substantially tangential to a wall disposed at the periphery of the rotary surface; withdrawing the items aligned in a predetermined orientation from the rotary surface through a discharge aperture in the peripheral wall; detecting a presence of an item in the discharge aperture; calculating a duration of the presence of the item at a predetermined location; comparing the duration to a threshold duration wherein the threshold duration is a maximum time of the presence of the item at the predetermined location and after which the item is considered as obstructing the discharge aperture; and extending an extendable arm through the discharge aperture, if the calculated duration is longer than the threshold duration, the extendable arm in the extended position abutting the item obstructing the discharge aperture and pushing the item towards the center of the rotary surface, away from the discharge aperture. 
     Another object of the invention provides a feeder for orienting and aligning disorderly incoming articles in combination with an article spacer for spacing the aligned and oriented articles. The feeder comprises: a table having a peripheral wall, a rotary surface surrounded by the peripheral wall, and a discharge substantially tangential to the peripheral wall, the discharge being sized to receive one article at a time from the rotary surface in a predetermined orientation; and a first carrier disposed proximate to the discharge, the first carrier withdrawing, from the rotary surface, the articles introduced into the discharge, the first carrier cooperating with the article spacer to provide a distance between two consecutive articles withdrawn from the feeder. 
     Another object of the invention provides an apparatus for aligning and spacing items. The apparatus comprises: a rotatable table having a peripheral wall and a discharge opening in the peripheral wall, the discharge opening allowing the items in a predetermined orientation to be successively withdrawn from the rotatable table in a single file line, the rotatable table being fed with disorderly items; a first carrier disposed proximate to the discharge opening, the first carrier recovering the oriented items exiting through the discharge opening; and an item spacer mounted proximate to the first carrier, the item spacer providing a predetermined spacing between two consecutive oriented items. 
     A further object of the invention provides a method for aligning and spacing items. The method comprises: feeding a rotary surface with the items; driving the rotary surface in rotation; aligning the items substantially tangential to a wall disposed at the periphery of the rotary surface; withdrawing the items aligned in a predetermined orientation from the rotary surface through a discharge aperture in the peripheral wall; carrying the items withdrawn from the discharge aperture on a first carrier; and providing a spacing between two consecutive items withdrawn from the discharge aperture and carried by the first carrier. 
     A further aspect of the invention provides a feeder for orienting and aligning disorderly incoming articles. The feeder comprises: a table having a peripheral wall, a rotary surface surrounded by the peripheral wall, and a discharge substantially tangential to the peripheral wall, the discharge being sized to receive one article at a time from the rotary surface in a predetermined orientation; at least one pile eliminating member extending above the rotary surface and defining a gap therewith, the gap being sized to solely permit passage of non-superposed articles; and a rotary misaligned article eliminating member disposed over the rotary surface, spaced from the peripheral wall by a distance sufficient to permit only articles in the predetermined orientation to circulate therebetween, and rotatable in a direction dislodging the articles not in the predetermined orientation. 
     Another aspect of the invention provides a method for orienting and aligning disorderly incoming articles. The method comprises: feeding a rotary surface with the articles; driving the rotary surface to carry the articles to a discharge aperture defined in a peripheral wall surrounding the rotary surface, the discharge aperture being configured to only permit passage of one properly oriented article at a time; eliminating article piles on the rotary surface proximate to the peripheral wall; displacing with a rotary misaligned article eliminating member, spaced apart from the peripheral wall, articles not in the predetermined orientation towards the center of the rotary surface, away from the peripheral wall; and individually withdrawing properly oriented articles from the rotary surface through the discharge aperture. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which: 
         FIG. 1  is a perspective view of a feeder followed by a block spacer in accordance with an embodiment of the invention; 
         FIG. 2  is a perspective view of a frame for supporting a rotary surface in accordance with an embodiment of the invention; 
         FIG. 3  is a perspective view, fragmented and enlarged, of a discharge aperture of the feeder shown in  FIG. 1 ; 
         FIG. 4  is a perspective view, fragmented and enlarged, of a longitudinal brush conveyor extending over the rotary surface in accordance with an embodiment of the invention; 
         FIG. 5  is a perspective view, fragmented and enlarged, of a dislodging arm of the feeder shown in  FIG. 1 , in the retracted position; 
         FIG. 6  is a perspective view, fragmented and enlarged, of the dislodging arm shown in  FIG. 6 , in the extended position; 
         FIG. 7  is a perspective view of the block spacer shown in  FIG. 1 ; 
         FIG. 8  is a perspective view of the block spacer in accordance with another embodiment of the invention, with feed rolls; 
         FIG. 9  is a perspective view of the feed rolls of the block spacer shown in  FIG. 8 ; 
         FIG. 10  is a side elevation view of the feed rolls of the block spacer shown in  FIG. 8 ; 
         FIG. 11  is a perspective view of the block spacer in accordance with another embodiment of the invention; 
         FIG. 12  is a perspective view of a barrier member of the block spacer shown in  FIG. 11 ; and 
         FIG. 13  is a perspective view of the barrier member of the block spacer shown in  FIG. 11  with the barrier member abutting one block. 
     
    
    
     It will be noted that throughout the appended drawings, like features are identified by like reference numerals. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings and, more particularly, to  FIG. 1 , there is shown a disk singulator, a feeder or a feeding apparatus for aligning and orienting blocks  22 . According to one embodiment of the present invention, the feeder is provided in the form of a turn table or rotary table  20 . The rotary table  20  includes a frame  26  with supporting wheels  28  disposed at the periphery of the frame  26  and on which a rotary surface  24  is rotatably disposed. Referring now to  FIG. 2 , it will be seen that the frame  26  includes an actuator  29 , such as a gear motor, operatively connected to the rotary surface  24  for rotating the latter. One skilled in the art will appreciate that various types of actuators could be used to drive the rotary surface  24 . For instance, it is contemplated to use an hydraulic motor. The rotary surface  24  is fed with the blocks  22 , as will be described in more details below. 
     Referring back to  FIG. 1 , there is shown that the rotary surface  24  is surrounded by a peripheral wall  30 , which is fixedly mounted to the frame  26 . By rotating, the rotary surface  24 , the blocks  22  are transferred towards the peripheral wall  30  by centrifugal force. The peripheral wall  30  guides the blocks  22  towards a discharge aperture  32 , or block discharge. The shape and size of the discharge aperture  32  permits only correctly oriented blocks  22  to pass one at a time therethrough, or one block in a predetermined orientation. 
     A disorderly block feeder  44 , such as a conveyor  45  or any other means known by those skilled in the art, feeds the rotary table  20  with the blocks  22 . The disorderly block feeder  44  extends above the rotary surface  24 . The blocks  22  are fed randomly on the rotary table  20 . 
     The rotary surface  24  is preferably substantially flat but it can also include a conical central member  46  for facilitating the transfer of the blocks  22  towards the peripheral wall  30 , especially when the rotary surface diameter is relatively important (typically above eight (8) feet). 
     The rotary surface  24  can preferably be rotated in both directions, as will be described in more details below. However, for aligning and orienting the blocks  22 , the rotary surface  24  is rotated in the direction of the discharge aperture  32 , represented by arrow  48 . 
     Referring now to  FIG. 3 , it will be seen that the discharge aperture  32  is substantially tangential to the peripheral wall  30  for withdrawing only the blocks  22  oriented substantially tangential to the peripheral wall  30 . A discharge track  34  is juxtaposed to the discharge aperture  32  for supporting the blocks  22  withdrawn from the rotary surface  24 . Inner and outer guide members  36 ,  38  are mounted on each side of the discharge track  34  for guiding the blocks  22 . The outer guide member  38  is contiguous and tangential to the peripheral wall  30  on a first side of the discharge aperture  32 . The inner guide member  36  is juxtaposed to the peripheral wall  30  on the opposite side of the discharge aperture  32 . The discharge track  34  is followed by a first conveyor  42  ( FIG. 1 ), as will be described in more details below. 
     For clarity, the blocks  22  will be characterized by a length, a width, and a thickness. The width of the blocks  22  corresponds substantially to the width (or size) of the discharge aperture  32 . When the blocks  22  are withdrawn from the rotary table  20  in the predetermined orientation, the width of the blocks  22  is substantially parallel to the rotary surface  24 , i.e. one face of the block  22  lays on the rotary surface  24 . The thickness of the blocks  22  corresponds to the vertically extending dimension when the blocks are withdrawn from the rotary table  20 . The length of the blocks  22  is the remaining dimension and corresponds to the dimension parallel to the first conveyor  42  when the blocks  22  are disposed thereon. For blocks  22 , the length is the longest dimension. The thickness is typically the shortest dimension. 
     Referring to  FIGS. 1 ,  2 , and  4 , it will be seen that the rotary table  20  also includes two overhead longitudinal brush conveyors  50  for eliminating block piles ( FIG. 4 ) and reducing the probabilities of obstruction of the discharge aperture  32 . The brush conveyors  50  extend from the peripheral wall  30  above the rotary surface  24 . The brush conveyors  50  include an endless belt covered with bristles sufficiently stiff for moving the blocks  22 . The brush conveyors  50  preferably rotate in a direction for bringing the blocks  22  towards the center of the rotary table  20 , represented by arrow  51  ( FIG. 3 ). One skilled in the art will appreciate that the rotary table  20  can include one or more longitudinal brush conveyors  50 . The brush conveyors  50  are disposed over the rotary surface  24  at a distance, or a gap, allowing only non-superposed blocks  22  to circulate between the brush conveyor  50  and the rotary surface  24  in the orientation wherein the width of the block  22  is substantially parallel to the rotary surface  24 , i.e. the face of the block  22  is in contact with the rotary surface  24 . The distance between the brush conveyor  50  and the rotary surface  24  is preferably adjustable in accordance with the thickness of the blocks  22  being aligned and oriented. The gap between the brush conveyor  50  and the rotary surface  24  can also be adjusted to flip the blocks  22  that do not have their face in contact with the rotary surface  24 . 
     As shown in  FIG. 3 , the brush conveyors  50  can be mounted to the frame  26  with L-shape supports  52  or any other appropriate supports. 
     Referring to  FIGS. 1 and 3 , it will be seen that the rotary table  20  can also include a rotary brush  53  that moves the blocks  22 , which are not adequately aligned with the discharge aperture  32  and in the predetermined orientation or not enough proximate to the peripheral wall  30  away from the peripheral wall  30  to reduce the probabilities of obstruction of the discharge aperture  32 . The rotary brush  53  preferably rotates in the direction of arrow  54  for propulsing away from the peripheral wall  30  the misaligned blocks  22 . 
     The rotation axis of the rotary brush  53  shown in  FIG. 3  is substantially horizontal and parallel to the rotary surface  24 . One skilled in the art will appreciate that the rotation axis of the rotary brush  53  can also be in a substantially vertical orientation or any other orientation. 
     The rotary brush  53  is mounted over the rotary surface  24  at a distance shorter than the thickness of the blocks  22 , proximate to the discharge aperture  32 , upstream therefrom. The rotary brush  53  is preferably mounted over the rotary surface  24  at a distance from the peripheral wall  30  allowing the blocks  22  in the predetermined orientation to pass between the rotary brush  53  and the peripheral wall  30 . The misaligned blocks  22  are moved away or displaced by the rotary brush  53  which pushes them away from the discharge aperture  32  towards the center of the rotary surface  24 . 
     The brush conveyors  50  are operatively connected to an actuator  55 , such as an electric motor, with a chain and sprocket assembly  56 . The rotary brush  53  mounted proximate to the discharge aperture  32  can be operatively connected to the brush conveyors  50  mounted proximate thereto with a second chain and sprocket assembly  57 . One skilled in the art will appreciate that other means can be used to transfer the motion between the actuator  55  and the brush conveyor  50  or between the brush conveyor  50  and the rotary brush  53  such as, without being limitative, a belt and pulley assembly. 
     One skilled in the art will appreciate that the brush conveyors  50  can be replaced by any block pile eliminating member extending above the rotary surface at a distance allowing one block having one face laying on or in contact with the rotary surface to circulate therebetween. 
     If one block  22  gets jammed into the discharge aperture  32 , several mechanisms can be used for dislodging the obstructing block  22   c . Referring to  FIGS. 5 and 6 , it will be seen that the rotary table  20  can include a dislodging arm  60 , or extendable arm, mounted proximate to the block discharge aperture  32 , the dislodging arm  60  being movable between a retracted position ( FIG. 5 ) and an extended position ( FIG. 6 ) for dislodging the obstructing block  22   c  from the discharge aperture  32  by applying a force to the obstructing block  22   c  in the extended position. The actuator  61  for moving the dislodging arm  60  between the extended and retracted positions is preferably a linear actuator such as a pneumatic cylinder or any other linear actuator those known to those skilled in the art. The dislodging arm  60  can include an impacting element  63  such as a rod attached to the actuator  61 . 
     In the retracted position, the dislodging arm  60  is preferably completely withdrawn from the rotary surface  24  and/or the discharge track  34  ( FIG. 5 ) while in the extended position, at least a section of the dislodging arm  60  extends above the rotary surface  24  and abuts the obstructing block  22   c  for removing the obstructing block  22   c  from the discharge aperture  32  and moving it towards the center of the rotary surface  24  for being aligned ( FIG. 6 ). As shown on  FIGS. 5 and 6 , the dislodging arm  60  is preferably mounted to the peripheral wall  30  proximate to the outer guide member  38 . 
     The rotary table  20  can also include at least one sensor  62  conceived for detecting a presence of one block  22  proximate to or in the discharge aperture  32  and a controller  66  for calculating a duration of the presence of the block  22  in the discharge aperture  32 . The duration of the presence of the block  22  in the discharge aperture  32  is compared by the controller  66  to a threshold duration. The threshold duration can be a maximum time of the presence of the block  22  in the discharge aperture  32  if the block  22  is not obstructing the discharge aperture  32 . If the calculated duration is longer than the threshold duration, the dislodging arm  60  is actuated for moving from the retracted position to the extended position for abutting the block  22   c  obstructing the discharge aperture  32 . The sensor can be positioned to detect blocks in the discharge aperture  32 , on the carrier  42  extending after the discharge aperture  32 , before the discharge aperture  32 , or at any other appropriate location known to one skilled in the art that allows the detection of the obstruction of the discharge aperture  32 . Once the obstructing block  22   c  is removed from the discharge aperture  32 , the dislodging arm  60  is retracted into the retracted position ( FIG. 5 ). 
     A second mechanism for dislodging the obstructing block  22  includes rotating the rotary surface  24  in the opposite rotation direction. As mentioned above, for aligning and widthdrawing the blocks  22  from the rotary surface  24 , the rotary surface  24  is rotated in the direction of the discharge aperture  32 , represented by arrow  48 , a first rotation direction. The actuator  29  for rotating the rotary surface  24  is preferably conceived for rotating the rotary surface  24  in both directions, the first rotation direction, represented by arrow  48 , and a second rotation direction, opposite to the first rotation direction. Therefore, if the block  22  obstructs the discharge aperture  32 , the rotation direction of the rotary surface  24  can be reversed for one of a predetermined time period and a predetermined rotation distance sufficient for dislodging the obstructing block  22 . Thereafter, if the block  22  has been dislodged from the discharge aperture  32 , the rotation direction of the rotary surface  24  is reversed and the rotary surface  24  is rotated in the first rotation direction, represented by arrow  48 . 
     The rotation speed of the rotary surface  24  in the second rotation direction can be slower or similar. 
     One skilled in the art will appreciate that both dislodging mechanisms described above can be combined for dislodging blocks  22  obstructing the discharge aperture  32 . 
     The discharge aperture  32  is juxtaposed to the discharge track  34 , which is followed by the first conveyor  42  which imparts to the blocks  22  traveling thereon a first traveling speed. Once past the discharge aperture  32 , the aligned and oriented blocks  22  are queued waiting to be fed to other machineries. If the oriented and aligned blocks  22  need to be fed at a controlled rate and/or timing, several mechanisms, or block spacers, can be used for providing the spacing or time interval between two consecutive blocks  22 . 
     Referring to  FIG. 7 , it will be seen one block spacer  68  for providing the spacing or time interval between two consecutive blocks  22   a ,  22   b . The first conveyor  42  is followed by a second conveyor  70  which imparts to the blocks  22  traveling thereon a second traveling speed. The blocks  22  carried by the first conveyor  42  are transferred to the second conveyor  70 . The second traveling speed imparted by the second conveyor  70  is faster than the first traveling speed imparted by the first conveyor  42 , thereby providing the spacing or the time interval between the two consecutive blocks  22   a ,  22   b . A bridging member  71  can be provided between the two conveyors  42 ,  70  for providing a smooth transfer of the blocks  22  from the first conveyor  42  to the second conveyor  70 . 
     If a predetermined spacing or time interval is required between the two consecutive blocks  22   a ,  22   b , the block spacer  68  can include a controller (not shown) for controlling the first and second traveling speeds. 
     An overhead member  80  can be mounted over the conveying surface of the first conveyor  42 . The overhead member  80  applies a small pressure on the top surface of the blocks  22  for preventing the blocks  22  to flip upwardly if the number of blocks  22  withdrawn from the rotary table  20  is too important relative to the capacity of the block spacer  68  and the blocks  22  apply a pressure on one another. In the embodiment of  FIG. 7 , the overhead member  80  includes a plurality of idle rollers or wheels  82  press against the top surface of the blocks  22  carried by the first conveyor  42 . The wheels  82  could also be driven. The wheels  82  apply a small pressure on the blocks  22  for transferring the traveling speed of the first conveyor  42  to the blocks  22   b.    
     Referring to  FIG. 8 , there is shown another block spacer  168  for providing a spacing or time interval between two consecutive blocks  22   a ,  22   b . The features are numbered with reference numerals which correspond to the reference numerals of the previous embodiment in the 100 series. The block spacer  168  includes two feed rolls  178  having a constant rotation speed. The feed rolls  178  convey the blocks  22   a ,  22   b  withdrawn to a second conveyor (not shown) or directly to a processing apparatus (not shown) that needs to be fed with blocks  22  at intervals. The feed rolls  178  convey the blocks  22  at a faster speed that the conveying or traveling speed imparted by the first conveyor  42 . 
     The block spacer  168  can also include a controller (not shown) for controlling the rotation speed of the feed rolls  178  and the conveying speed of the second conveyor, if any, for providing one of a predetermined distance and a predetermined time lapse between the two consecutive blocks  22   a ,  22   b.    
     Referring to  FIGS. 9 and 10 , it will be seen that the blocks  22  ( FIG. 8 ) are conveyed between both feed rolls  178 . The spacing between the feed rolls  178  is preferably adjusted in accordance with the thickness of the blocks  22  carried. One skilled in the art will appreciate that the block spacer  168  can include only one feed roll  178  or one driven feed roll  178   a  and one idler feed roll  178   b . Preferably, the lower feed roll  178   a  is the driven roll and the upper feed roll  178   b  is the idler roll but one skilled in the art will appreciate that both rolls  178   a ,  178   b  can be driven rolls. The upper feed roll  178   b  can have an adjustable height in a manner such that a low pressure is applied to the blocks  22  carried between the feed rolls  178 . 
     Referring back to  FIG. 8 , it will be seen that, as for the block spacer  68 , the block spacer  168  can include a bridging member  71  between the first conveyor  42  and the feed rolls  178  for providing a smooth transfer of the blocks  22  from the first conveyor  42  to the the feed rolls  178 . A top guard  180  is mounted over the first conveyor  42 . The top guard  180  is mounted above the blocks  22  conveyed by the first conveyor  42  and does not apply pressure on the blocks  22  carried by the conveyor  42  in normal operation. The top guard  180  is only abutted by the blocks  22  when they begin to flip upwardly. The top guard  180  acts as a security system. 
     The block spacer  168  shown in  FIGS. 8 to 10  can be operated differently while still providing a spacing or time interval between two consecutive blocks  22   a ,  22   b . The feed rolls  178  can be adapted to be in one of a rotating state and a stationary state. The feed rolls  178  are in the rotating state for conveying the blocks  22  to one of a second conveyor (not shown) or a processing apparatus (not shown) such as a finger jointer. The feed rolls  178  are in the stationary state for distancing the two consecutive blocks  22   a ,  22   b . The relative duration of the state of the feed rolls  178  determines the spacing between the two consecutive blocks  22   a ,  22   b . A servo-motor or any other appropriate actuator known to one skilled in the art can be used to drive the feed rolls  178 . 
     If a predetermined spacing or time interval is required between the two consecutive blocks  22   a ,  22   b , the block spacer  168  can include a controller (not shown) for controlling the state of the feed rolls  178 . 
     Referring to  FIGS. 11 to 13 , it will be seen another block spacer  268  for providing a spacing or time interval between two consecutive blocks  22   a ,  22   b . The features are numbered with reference numerals which correspond to the reference numerals of the previous embodiments in the 200 series. The first conveyor  42  is followed by a second conveyor  270 . The block spacer  268  also includes a barrier member  284  disposed between the first and the second conveyors  42 ,  270 . The barrier member  284  is movable between a closed position preventing the passage of the blocks  22  from the first conveyor  42  to the second conveyor  270  and an open position allowing the passage of the blocks  22  from the first conveyor  42  to the second conveyor  270 . 
     The barrier member  284  of the block spacer  268  has substantially a U-shape with a central member  286  and two legs  288  extending from a respective end of the central member  286 . The free ends  290  of both legs  288  are pivotally mounted two support members  291 , disposed on a respective side of the second conveyor  270 , however one skilled in the art will appreciate that they can be mounted on a respective side of the first conveyor  42 . Two extendable arms  292 , such as linear actuators, are secured on a respective leg  288 , proximate to the junction with the central member  286 . The extendable arms  292  move between an extended position wherein the barrier member  284  is in the open position and a retracted position wherein the barrier member  284  is in the closed position. One skilled in the art will appreciate that any mechanism allowing the barrier member  284  to move between the open and the closed positions can be used such as pneumatic cylinders, hydraulic cylinders, electric solenoids, cam, crankshaft, and the like. Only one extendable arm  292  can be used. Moreover, the structure of the barrier member  284  and its mechanism can differ from the one shown in  FIGS. 11 to 13  and described above. 
     Two abutting wheels  294  are rotatably mounted to the central member  286  of the barrier member  284 . As shown on  FIG. 13 , the abutting wheels  294  of the barrier member  284  abut the block  22   b  being transferred from the first conveyor  42  to the second conveyor  270 . The abutting wheels  294  apply a small pressure on the block  22   b  for transferring the speed of the second conveyor  270 , which is faster than the speed of the first conveyor  42 , to the block  22   b . The small pressure applied by the wheels  294  to the blocks  22   b  closes the barrier member  284  closes when the whole block  22   b  is transferred to the second conveyor  270 , thereby preventing the following block  22  to be transferred to the second conveyor  270 . 
     As for the previous block spacers  68 ,  168 , the block spacer  168  can include a bridging member  271  between the first conveyor  42  and the second conveyor  270  for providing a smooth transfer of the blocks  22  from the first conveyor  42  to the the second conveyor  270 . An top guard  280 , similar to the top guard  180 , is mounted over the first conveyor  42 . 
     The block spacer  268  can also include a controller (not shown) for controlling the movement of the barrier member  284  between the open and the closed positions and/or the speed of the second conveyor  270  for providing one of a predetermined distance and a predetermined time lapse between the two consecutive blocks  22   a ,  22   b.    
     The combination of the rotary table  20 , and the block spacers  68 ,  168 ,  268  permits to orient and align elongaged blocks  22  from a disorderly supply and to feed the oriented and aligned blocks  22  at controlled intervals to another processing apparatus such as a wood working machine such as finger jointers, a scanning equipment and the like. 
     The blocks  22  can be wood blocks, plastic blocks or any other blocks that need to be oriented and aligned. The wood blocks can need to be aligned and oriented for feeding wood working machines such as finger jointers or scanning equipment, for instance. The blocks  22  can be elongated blocks having preferably a length longer than the thickness and the width. One skilled in the art will appreciate that short items can also be aligned and oriented with the above described apparatus. 
     The rotary table  20  and the block spacers  68 ,  168 ,  268  combined with the means for disloging obtrusting blocks  22  from the discharge aperture  32  are adapted for blocks having a random length distribution. 
     The feeder or the rotary table  20  described above allows to orient and aligned items having a length distribution. The probabilities of block wedging at the discharge aperture  32  are reduced because the block piles are destroyed upstream the discharge aperture  32  and the misaligned blocks are removed from the discharge aperture  32 . 
     The blocks obstruct the discharge aperture  32 , automated mechanisms are available for dislodging an obstruing block  22  from the discharge aperture  32 . Moreover, it is possible to automatically space consecutive blocks  22   a ,  22   b  withdrawn from the rotary table  20 . 
     In the wood industries, the aligned and oriented blocks  22  can be transferred or fed to wood working machines or scanning equipment, for instance. 
     The feeder allows to achieve high feed rates with a minimum or no human intervention. 
     The embodiments of the invention described above are intended to be exemplary only. One skilled in the art will appreciate that the discharge aperture  32  can be directly followed by the first conveyor  42  instead of being followed by the discharge track  34 . One skilled in the art will appreciate that the first and second conveyors  42 ,  70 ,  270  can be replaced by any appropriate block carrier. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.