Abstract:
An embroidering sewing machine comprising a needle vertically reciprocated to stitch a work; an embroidering frame for holding the work to be stitched; a base ( 2 ) enclosed to provide a predetermined space therein; a driver means arranged in the base ( 2 ) and including a carriage assembly operatively connected to the embroidering frame and operated in synchronism with vertical movement of the needle to move in X-direction and in Y-direction normal to X-direction, the carriage assembly including a base carriage ( 5 ) movable in X-direction, an intermediate carriage ( 6 ) operatively connected to the base carriage ( 5 ) to move therewith and being movable in Y-direction relative to the base carriage ( 5 ), a distal end carriage ( 7 ) operatively connected to the intermediate carriage ( 6 ) to move therewith; a transmission means arranged between the intermediate carriage ( 6 ) and the distal end carriage ( 7 ) and transmitting the movement of the intermediate carriage ( 6 ) to the distal end carriage ( 7 ) to move the distal end carriage ( 7 ).

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a sewing machine, more particularly relates to an embroidering sewing machine having a needle vertically reciprocated relative to a work held on an embroidering frame to be stitched and an embroidering frame driver including a carriage which is operatively connected to the embroidering frame and is operated in synchronism with vertical reciprocation of the needle to move in a first direction and in a second direction normal to the first direction, thereby to move the embroidering frame in accordance with the movement of the carriage relative to the needle. 
     2. Prior Art 
     It has been generally known that the embroidering sewing machine has a driver for drivingly moving embroidering frame holding a work to be stitched. The embroidering frame driver includes a carriage operatively connected to the embroidering frame and is operated in synchronism with vertical reciprocation of the needle to move in a first direction (X-direction) and in a direction (Y-direction) normal to the first direction. The embroidering frame driver is normally arranged in a base of the sewing machine or in a casing which is separated from the sewing machine. In any case, the carriage is partly extended out of the base or the casing to hold the embroidering frame which is to be moved in accordance with movement of the carriage relative to the needle. 
     Therefore, the area where the embroidering frame driver including a carriage can move is determined by the size of sewing machine or by the size of the embroidering frame driver because the embroidering frame driver can not move the machine beyond a limited size of the base of the sewing machine or a limited size of separate casing in which the embroidering frame driver is housed. This makes it impossible to continuously stitch a large sized pattern without interruption of stitching operation. In order to stitch a large sized pattern, it has been required to reset the work to the embroidering frame so often while the sewing machine is stopped until the pattern is completed. 
     For the purpose of solving this problem, it has been designed to enlarge the base of sewing machine or the separate casing in which the embroidering frame is housed, thereby to enlarge the area where stitching operation is performed. Such a sewing machine will be inevitably bulky and heavy and, therefore, will not be adapted to being used in the houses in general. 
     OBJECT OF THE INVENTION 
     The invention has been provided to eliminate the defects and disadvantages of the prior art. 
     It is, therefore, an object of the invention to provide an embroidering sewing machine which may stitch a large sized pattern continuously without interruption of stitching operation halfway for resetting a work to the embroidering frame. 
     It is another object of the invention to provide an embroidering sewing machine which is compact is structure and smooth in operation. 
     It is another object of the invention to provide a embroidering sewing machine including a carriage assembly which accomplish a amplified motion exceeding the size of the carriage assembly per se. 
     It is still another object of the invention to make it possible to use a relatively large sized embroidering frame to stitch a relatively large sized pattern. 
     SUMMARY OF THE INVENTION 
     For attaining the objects, the embroidering sewing machine of the invention having an embroidering frame for holding the work to be stitched, comprises a first drive means operated in synchronism with vertical reciprocating movement of a needle to move the embroidering frame in a first direction and a second drive means operated in synchronism with vertical reciprocating movement of the needle to move the embroidering frame in a second direction normal to the first direction, wherein: at least one of said first and second drive means comprises; a movable means which reciprocatingly moves in a limited area in said first or second direction, and a motion amplifying means to amplify the movement of said movable means and transmit it to said embroidering frame, thereby to move said embroidering frame in the range exceeding said limited area. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an embroidering sewing machine according to the invention; 
     FIG. 2 is a plan elevational view of a base of the sewing machine laterally sectioned to show the interior thereof, 
     FIG.  3 (A) is an enlarged plan elevational view of a carriage drive device of the sewing machine; 
     FIG.  3 (B) is a further enlarged plan elevational view of an essential part of the carriage drive device of the sewing machine; 
     FIG.  4 (A) is an enlarged perspective view of the carriage drive device composed of a base carriage, an intermediate carriage, a distal end carriage and transmission belts; 
     FIG.  4 (B) is a perspective view of a part of the carriage drive device; 
     FIG.  5 (A) through FIG.  5 (C) are plan elevational views of the carriage drive device for explaining the operations thereof, 
     FIG. 6 is a perspective view of a second embodiment of the carriage drive device shown in combination with X-Y drive mechanism; 
     FIG. 7 is a plan elevational view of the carriage drive device shown in lateral section; 
     FIG. 8 is a perspective view of the carriage drive device partly broken to show the interior thereof; 
     FIG.  9 (A) is a perspective view of the carriage drive device shown in combination with X-Y drive mechanism; 
     FIG.  9 (B) is a plan elevational view of a modified embodiment of transmission belt which may be employed in the embodiment; 
     FIG.  10 (A) is a plan elevational views of a transmission belt of the carriage drive device shown as is at the initial position; 
     FIG.  10 (B) is a plan elevational views of a transmission belt of the carriage drive device shown as is moved to maximum extent; 
     FIG.  11 (A) through FIG.  11 (C) are plan elevational views of the carriage drive device for explaining the operations thereof; 
     FIG.  12 (A) is a perspective view of a slightly modified embodiment of the carriage drive device shown as partly broken; 
     FIG.  12 (B) is a plan elevational view of the modified embodiment of FIG.  12 (A); 
     FIG. 13 is a perspective view of a third embodiment of the carriage drive device; 
     FIG. 14 is a perspective view of a fourth embodiment of the carriage drive device; in combination with X-Y drive mechanism: 
     FIG.  15 (A) and FIG.  15 (B) are perspective views of the embodiment for explaining the operations thereof; 
     FIG.  16 (A) is a plan elevational view of the embodiment wherein the carriage assembly is at the initial position; 
     FIG.  16 (B) is a plan elevational views of the embodiment wherein the carriage assembly is moved to maximum extent from the initial position; and 
     FIG.  17 (A) through FIG.  17 (C) are elevational views of the embodiment for explaining the operations of the carriage drive device. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The invention will now be described in reference to the attached drawings. FIG. 1 shows the outline of a sewing machine. FIG. 2 is a plan elevational view of a base  2  of the sewing machine shown in lateral section to show the interior thereof wherein a X-Y drive device A is housed. 
     In an arm  1  of the sewing machine, there is provided a stitching device including a rotary drive shaft and a needle bar which is vertically reciprocated in association with rotation of the drive shaft. 
     The arrow X shows a width direction of the sewing machine while arrow Y shows a depth direction of the sewing machine. 
     The drive device A has a portion  20  to which an embroidering frame  21  is attached rearwardly of the base  2  in the direction Y. The embroidering frame attaching portion  20  is extended out of the base  2  through a guide groove  2   a  formed at the rear side of the base  2 . such that the embroidering frame  21  attached to the embroidering frame attaching portion  20  may be moved by the drive device A in the directions X and Y. 
     The embroidering frame attaching portion  20  is an extension end of an distal end carriage  7  which forms a carriage structure together with an intermediate carriage  6  and a base carriage  5  which is moved by a drive motor  19  only in the direction X. 
     As shown in FIG.  3 (A), the base carriage  5  is composed of a flat plate  5   a  extended in the direction Y and having a sectionally circular guide shaft  5   b   1  and a guide rail  5   b   2  which is located opposite to the guide shaft  5   b   1  in the direction X, the guide shaft and guide rail extending in the direction Y respectively. The guide shaft  5   b   1  is supported by beatings  5   a   1 ,  5   a   2  formed at the opposite sides of the flat plate  5   a  in the direction Y by bending up the flat plate  5   a  while the guide rail  5   b   2  is formed by bending up the flat plate  5   a  and further horizontally bent inside above the flat plate  5   a.    
     The flat plate  5   a  has a pair of opposite pulleys  8   a,    8   b  spaced from each other in the direction Y. An endless belt  9  is wound around the pulleys  8   a,    8   b  and is extended in parallel with the guide shaft  5   b   1 . 
     One of the pulleys  8   a,    8   b  is operatively connected to a drive motor  15  through a gear assembly  14 , the drive motor  15  being supported on lower side of the flat plate  5   a.  The drive motor  15  is driven to rotate one of the pulleys  8   a,    8   b,  thereby to move the endless belt around the pulleys  8   a,    8   b.  The gear assembly  14  includes a plurality of gears including an intermediate gear  14   b  in mesh with a drive gear of the motor  15  and a follower gear  14   a  which is in mesh with the intermediate gear  14   b  and coaxial with the pulley  8   a  to rotate the pulley  8   a  at a reduced speed, thereby to reduce the moving speed of the endless belt  9  which is moved around the pulleys  8   a,    8   b.    
     As shown in FIG.  4 (A), the intermediate carriage  6  has guide portions  6   c  formed at the opposite sides thereof in the direction X. One of the engaging portions  6   c  is in engagement with the guide rail  5   b   2  while the other two engaging portions  6   c  are in engagement with the guide shaft  5   b   1 . The intermediate carriage  6  has a portion  6   d  fixedly connected to the endless belt  9  at a connecting point indicated by Fo in FIG.  5 (A) through FIG.  5 (C) such that the intermediate carriage  6  may be reciprocatingly moved relative to the base carriage  5  in the direction Y as guided by the guide shaft  5   b   1  and the guide rail  5   b   2  when the drive motor  15  is driven. 
     The intermediate carriage  6  is a flat plate partly formed with a hollow frame  6   a  extending in the direction Y and further has a pair of opposite pulleys  10   a  located thereon spaced from each other in the direction Y. An endless belt  11  is wound around the pulleys  10   a.  The endless belt  11  is fixedly connected to the base carriage  5  at a point Fa defined as a connecting point. Precisely a connector  12  fixedly provided on the base carriage  5  as shown in FIG. ( 4 B) is fixedly connected to the belt  11  at one of the opposite sides thereof with the spaced pair of pulleys  10   a  located therebetween. 
     As shown in FIG.  5 (A) through FIG.  5 (C), the connector  12  is extended up through an elongated opening  6   a   1  formed at the flat plate of the intermediate carriage  6  and extending in the direction Y in parallel with the endless belt  11 . The length of the elongated opening  6   a   1  is more than the length of stroke of the intermediate carriage  6  in the direction Y. 
     Since the endless belt  11  is fixedly connected to the base carriage  5  at the point Fa which is located at one of the opposite sides of the endless belt  11  with the spaced pair of pulleys  10   a  located therebetween, the endless belt  11  is moved around the pulleys  10   a  as the intermediate carriage  6  is reciprocatingly moved in the direction Y relative to the base carriage  5 . 
     The distal end carriage  7  is operatively connected to the intermediate carriage  6  and is reciprocatingly moved relative thereto in the direction Y into and out of the hollow frame  6   a  of the intermediate carriage  6 . 
     The distal end carriage  7  is composed of an elongated flat hollow frame  7   a  extending in the direction Y and inserted into the hollow frame  6   a  of the intermediate carriage  6  and having an upstanding free end  20  to which an embroidering frame is attached. The distal end carriage  7  has an engaging portion  7   b  which is in sliding engagement with a guide shaft  6   b  provided on the intermediate carriage  6  and extending in the direction Y. The distal end carriage  7  is further fixedly connected to the endless belt  11  at a point Fb which is located at the other of the opposite sides of the endless belt  11  with a pair of spaced pulleys  10   a  being located therebetween. Precisely the distal end carriage  7  has a connector  13  formed thereon and fixedly connected to  7  the endless belt  11  at the point Fb as shown in FIG.  5 (A) through FIG.  5 (C). 
     It is preferred to provide one of the connecting point Fa and Fb at a position adjacent to one of the pulleys  10   a  and  10   b  and provide the other of the connecting point Fa and Fb at a position adjacent to the other of the pulleys  10   a  and  10   b.  With the connecting points Fa and Fb being thus positioned, the opposite sides of the endless belt  11  will obtain effective strokes respectively in the movements of opposite directions. 
     For example, as shown in FIG.  5 (A), when the connecting point Fa is moved to the position adjacent to the pulley  10   b  while the endless belt  11  is moved, the connecting point Fb is moved to the position adjacent to the pulley  10   a.  The positional relation is contrary as shown in FIG.  5 (C). Thus the connecting point Fb may be moved substantially the length of the endless belt  11  between the opposite pulleys  10   a  and  10   b  in the direction Y. Namely the intermediate carriage  6 , which is connected to the endless belt  11  at the connecting point Fa, may be reciprocatingly moved substantially the length of the endless belt  11  relative to the base carriage  5  between the opposite pulleys  10   a  and  10   b  in the direction Y. Therefore, the distal end carriage  7  connected to the endless belt  11  at the connecting point Fb may be reciprocatingly moved substantially the length of the endless belt  11  between the opposite pulleys  10   a  and  10   b  in the direction Y. 
     In this connection, the endless belt  11  is toothed and is in mesh with the toothed pulley as shown in FIG.  3 (B). However, the toothed belt may be replaced by a flat, V-belt or a wire in combination with the correspondingly designed pulley. 
     The base carriage  5  carrying the intermediate carriage  6  may be moved in the direction X by a drive motor  19  supported on the base plate  5   a  of the base carriage  5  as shown in FIG.  2  and FIG.  3 (A). The base carriage  5  is supported at the opposite ends thereof in the direction Y on a pair of spaced guide rails  16 ,  16  extending in the direction X. The base carriage  5  has an engaging portion  18  secured thereto and extending in the direction Y and being in slide engagement with the guide shaft  16 . The engaging portion  18  is fixedly connected to an endless belt  17   a  which is wound around a pair of pulleys  17   b  which are spaced from each other in the direction X. One of the pulleys  17   b  is operatively connected to the drive motor  19  and is rotated thereby such that the endless belt  17   a  may be moved around the pulleys  17   b  , thereby to move the base carriage  5  in the direction Y. Therefore, the end portion  20  of the distal end carriage  7  extended out of the base  2  through the guide groove  2   a,  to which an embroidering frame is attached, may be moved in the directions X and Y. 
     According to the embodiment of the invention, a single stage of carriage drive mechanism is disclosed including the intermediate carriage  6  and the distal end carriage  7 . It is, however, possible to occasionally provide a multi-stage of carriage drive mechanisms including plural set of the intermediate carriage  6  and the distal end carriage  7  to further increase the moving distance of the carriage carrying an embroidering frame. 
     The operations of the embodiment will now be described in reference to FIG.  5 (A) through FIG.  5 (C). 
     The intermediate carriage  6  is moved in the direction Y by the endless belt  9  which is operatively connected to the drive motor  15  and is moved thereby, the drive motor  15  being supported on the base carriage  5  and driven by control signal supplied from a control device (not shown). 
     Since the endless belt  11  is fixedly connected to the base carriage  5  at the point Fa, the endless belt  11  is moved in the direction Y around the pullets  10   a  and  10   b  as the intermediate carriage  6  is moved in the direction Y. 
     As shown in FIG.  5 (B), in case the intermediate carriage  6  is moved in the right direction from the position as shown in FIG.  5 (A), the connecting point Fb, which is located on the opposite side of the connecting point Fa, is moved in the same direction with the intermediate carriage  6 . It is, therefore, apparent that the distal end carriage  7 , which is fixedly connected to the endless belt  11  at the point Fb, is moved while the intermediate carriage  6  is moved and remains stopped while the intermediate carriage  6  is stopped. 
     Actually the distal end carriage  7  is moved in association with the movement of the endless belt  11 . Therefore, the moving amount of the distal end carriage  7  is determined by the moving amount of the endless belt  11  moving around the two pulleys  10   a  and  10   b.  Namely the movement amount of the distal end carriage  7  is equivalent to the moving amount of the endless belt  11 . Since the endless belt  11  is rotationally moved around the pulleys  10   a  and  10   b  and the opposite sides of the endless belt  11  are moved substantially in parallel with each other in the direction Y, one side moving in one direction while the opposite side moving in the opposite direction, it is apparent that the moving amount of one side of the endless belt  11  is equivalent to the moving amount of the opposite side of the endless belt  11 . Thus movement amount of the endless belt  11  is twice of the moving amount of the intermediate carriage  6 . Therefore, the movement amount of the distal end carriage  7  is twice of the moving amount of the intermediate carriage  6 . Namely provided that the moving amount of the intermediate carriage  6  is S, the movement amount of the distal end carriage  7  is  2 S. 
     More precisely, provided that the axial center of the pulley  10   b  is a reference moving point Q of the intermediate carriage  6 , the point Q is moved with a maximum stroke S indicating a maximum moving amount of the intermediate carriage  6  from the position as shown in FIG.  5 (A) where the intermediate carriage  6  is completely housed in the base carriage  5  to the position as shown in FIG.  5 (C) where the intermediate carriage  6  has been moved in maximum. 
     On the other hand, provided that the distal end  7   c  of the distal end carriage  7  is a reference moving point P of the distal end carriage  7 , the point P is moved with a maximum stroke  2 S indicating a maximum moving amount of the distal end carriage  7  from the position as shown in FIG.  5 (A) where the distal end carriage  7  is completely housed in the base carriage  5  to the position as shown in FIG.  5 (C) where the distal end carriage  7  has been moved in maximum. 
     Thus it is possible to obtain, in the direction Y an extremely increased moving amount of the distal end carriage  7  having the distal end  20  to which an embroidering frame is attached, the distal end carriage  7  being otherwise placed under limitation of movement in the base  2  of sewing machine. 
     Subsequently, a second embodiment of the invention will be described. 
     According to the second embodiment, there is provided a carriage assembly including a carriage  44  and a distal end carriage  47  operatively connected to the carriage  44  and being capable of moving in X and Y directions. The distal end carriage  47  has a distal end  47   a  to which an embroidering frame is attached by means of an adapter  53 . 
     A pair of guide rails  35 ,  35 ′ are provided as extending in the direction X and supported on bearings  37 . Another pair of guide rails  36 ,  36 ′ are provided as extending in the direction Y and supported on bearings  37 . A pair of endless belts  38 ,  38 ′ are provided as extending in the direction Y along the guide rails  35 ,  35 ′ respectively and wound around a pair of pulleys  40  secured to the guide rails  35 ,  35 ′ respectively. Another pair of endless belts  39 ,  39 ′ are provided as extending in the direction Y along the guide rails  36 ,  36 ′ and wound around a pair of pulleys  40  secures to the guide rails  36 ,  36 ′ respectively. The pulley  40  are operatively connected to drive motors M respectively and rotated by the motors to move the endless belts there around. 
     As particularly shown in FIG. 9, an X-direction carrier  41  includes slide members  41   a,    41   b  oppositely located in the direction Y as slidably mounted on the guide rails  35 ,  35 ′ respectively and a member  41   c  for connecting the two slide members  41   a,    41   b  . The slide members  41   a,    41   b  are fixedly connected to the endless belts  38 ,  38 ′ respectively so as to be slidingly moved along the guide rails  35 ,  35 ′ as the endless belts  38 ,  38 ′ are moved. 
     A Y-direction carrier  42  includes slide members  42   a,    42   b  oppositely located in the direction X as slidably mounted on the guide rails  36 ,  36 ′ respectively and guide shafts  42   c  connecting the two slide members  41   a,    41   b.  The slide members  41   a,    41   b  are fixedly connected to the endless belts  39 ,  39 ′ respectively so as to be slidingly moved along the guide rails  35 ,  35 ′ as the endless belts  39 ,  39 ′ are moved. 
     As shown in FIG. 6, a slide member  43  is mounted on the on the guide shafts  42   c  and is slidingly movable therealong. 
     The carriage  44  has one end fixedly connected to the slide member  43  and has the opposite end mounted on the carrier  41  so as to be slidingly movable in the direction Y. 
     As shown in FIG. 7, a pair of pulleys  45   a,    45   b  are rotatably mounted on the carriage  44  with the central axes thereof being displaced in the direction X in the manner that a tangent line is common to the two pulleys  45   a,    45   b  and is in alignment with the Y axis. A cord-belt  49  is wound around the pulleys  45   a,    45   b  in formation generally of S-shape. The belt  49  has one end  49   a  fixedly connected to the slide member  41   a  and the opposite end  49   b  fixedly connected to the slide member  41   b.    
     As shown in FIGS. 7,  8  and  9 , a pair of guide shafts  46 ,  46  are provided on the base carriage  44  as extended in the direction Y with a predetermined space provided therebetween in the direction X for enabling the distal end carriage  47  to reciprocatingly move in the direction Y. 
     The distal end carriage  47  has a pair of engaging portions  48 ,  48  which are in slide engagement with the guide shafts  46 ,  46  respectively. One of the engaging portions  48 ,  48  is fixedly connected to the belt  49  at the point F located between the two pulleys  45   a,    45   b.    
     As the carriage  44  is moved in the direction Y, the belt  49  is rotatingly moved around the pulleys  45   a,    45   b.  The connecting point F is linearly moved with the carriage  44  in the same direction between the two pulleys  45   a,    45   b.    
     The distal end carriage  47  is moved in association with the movement of the belt  49  which is moved in association with the carriage  44 . Therefore, the moving amount of the distal end carriage  47  is determined by the moving amount of the belt  49  which is twice of the moving amount of carriage  44  on the reason as has been already described hereinbefore in connection with the first embodiment of the invention. Therefore, the movement amount of the distal end carriage  47  is twice of the moving amount of the carriage  44 . Namely provided that the moving amount of the carriage  44  is S, the movement amount of the distal end carriage  47  is  2 S. 
     As shown in FIG.  11 (C), the length L is an addition of a maximum moving amount La of the carriage  44  and a maximum moving amount Lb of the distal end carriage  47  to the right in the direction Y, wherein La equals Lb. In this connection, FIG.  9 (B) shows in detail a part of a toothed  19  which is in mesh with a toothed pulley  15 , which may be employed in place of the cord-belt  49  and the corresponding pulleys  45   a,    45   b.  Further a wire may be used in place of the cord-belt  49 . 
     FIG.  12 (A) and FIG.  12 (B) show a modified embodiment wherein one of the pulleys  45   a,    45   b,  that is, the pulley  45   b  is arranged to rotate in vertical plane and is mounted to the distal end carriage  47  while the position at which the end  49   b  of the belt  49  is fixed differs from the opposite end  49   a  in vertical direction. 
     FIG. 13 shows a third embodiment of the invention, wherein a carriage drive belt assembly  50  is mounted on the X-direction carrier  41  to move the carriage  44  in the direction Y. The carriage drive belt assembly  50  includes a drive belt  50   a  wound around a pair of pulleys  50   b  located on the X-direction carrier  41  as spaced from each other in the direction Y. The drive belt  50   a  is fixedly connected to the carriage  44  by means of a connector  51 . One of the pulleys  50   b  is operatively connected to a drive motor  52  mounted on the X-direction carrier  41  to be rotated thereby. Thus the drive belt  50   a  is rotatingly moved around the pulleys  50   b  to slidingly move the carriage  44  in the direction Y. 
     A fourth embodiment of the invention will be described in reference to FIGS. 14 through 17, wherein an intermediate support assembly  60  is additionally employed in the embodiment as shown in FIG.  6 . Therefore, the common elements are designated with the same reference numerals. 
     A carriage  44  has a guide  44   a  provided at the distal end thereof in the direction Y. A slide carriage  57  is composed of a pair of slide shafts  57   b  extending in the direction Y and having a support  57   a  secured to one end thereof for supporting an embroidering frame and having a stopper  57   c  secured to the opposite end thereof. The pair of slide shafts  57   b  are extended through a pair of guide holes  44   a   1  of the guide  44   a.    
     The stopper  57   c  of the slide carriage  57  is fixedly connected to a cord  49  at a point F 2 , the cord  19  being wound around a pair of pulleys  45   a,    45   b  located on the carriage  44  with a predetermined space provided therebetween in the direction Y and displaced in the direction X. The cord  49  has one end  49   a  secured to a carrier  41 a and the opposite end  49   b  secured to a carrier  41   b.  The connecting point F 2  is located at a part of the cord  49  extending between two pulleys  45   a,    45   b.    
     An intermediate support assembly  60  is provided, which is composed of a support  60   a  and a pair of shafts  60   b  extending in parallel with each other in the direction Y from the support  60   a  and passing through guide holes  44   a   2  formed at the guide  44   a  and further passing through guide portions  44   c  of the carriage  44  such that the intermediate support assembly  60  may slidingly moved relative to the carriage  44  in a stabilized condition. The slide shafts  57   b  of the slide carriage  57  are extended through guide holes  60   a   1  formed at the support  60   a  such that the intermediate support assembly  60  and the slide carriage  57  may be slidingly movable relative to each other. 
     The slide carriage  57  has a rack  63  extended in the direction Y and being opposite to a rack  64  provided on the carriage  44  and extending in the direction Y. A connector  61  is provided, which is extended in the direction X and has one end fixedly connected to one of the shafts  60   b  of the intermediate support assembly  60 . The connector  61  has a pinion  62  mounted to the opposite end thereof. The pinion  62  is located between the rack  63  and the rack  64  and is in mesh with both racks  63 ,  64  such that the slide carriage  57  and the intermediate support assembly  60  may be moved in association with movement of the carriage  44  in the direction Y. 
     The pinion  62  and the racks  63 ,  64  are designed move the intermediate support assembly  60  half of a distance that the slide carriage  57  is moved. Thus the intermediate support assembly  60  supports the slide carriage  57  at the intermediate portion thereof in case the slide carriage  57  is moved out to a maximum extent. 
     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations or modifications are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims.