Patent Publication Number: US-8985422-B2

Title: Accumulating apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to an accumulating apparatus for accumulating continuous sheet supplied from an upstream apparatus while continuously feeding the continuous sheet to a downstream apparatus. 
     2. Description of the Related Art 
     Conventionally, a system where various processes are applied to continuous sheet while the continuous sheet is continuously conveyed to continuously manufacture products such as disposable diapers, is in practical use. In such a system, an accumulating apparatus is provided between an upstream supplying apparatus for drawing continuous sheet from wound sheet where the continuous sheet is wound like a roll (hereinafter the wound sheet is simply referred to as a “wound roll”) and a downstream manufacturing apparatus for sequentially applying processes to each portion of the continuous sheet. 
     In the accumulating apparatus, a plurality of upper rollers are located topside in a vertical direction and a plurality of lower rollers are located downside in the vertical direction. The continuous sheet is held in contact with the upper rollers and the lower rollers alternately to be conveyed, and therefore the continuous sheet supplied from the upstream supplying apparatus is accumulated while being continuously fed to the downstream manufacturing apparatus. When the remaining amount of the continuous sheet in the wound roll becomes low, supply of the continuous sheet from the supplying apparatus is stopped and a distance between the upper rollers and the lower rollers is decreased to keep feeding the continuous sheet to the manufacturing apparatus (see, for example, Japanese Patent Application Laid-Open No. 7-137899). Then, the continuous sheet is cut from the wound roll and spliced to an end of continuous sheet of a new wound roll in the supplying apparatus, and therefore it is possible to switch the wound roll with the low remaining amount to new wound roll, without stopping the downstream manufacturing apparatus. 
     In the above accumulating apparatus, the distance between the upper rollers and the lower rollers can be changed by moving the upper rollers or the lower rollers in the vertical direction. However, since normally the weights of the rollers are large, a mechanism for moving the rollers in the vertical direction becomes large in size and also manufacturing costs of the accumulating apparatus increase. 
     SUMMARY OF THE INVENTION 
     The present invention is intended for an accumulating apparatus for accumulating continuous sheet supplied from an upstream apparatus while continuously feeding the continuous sheet to a downstream apparatus. It is an object of the present invention to downsize or omit a mechanism for changing the distance between the upper rollers and the lower rollers in the accumulating apparatus. 
     The accumulating apparatus according to the present invention comprises: an upper arm and a lower arm; and a distance changing mechanism for simultaneously moving the upper arm and the lower arm opposite to each other with respect to a vertical direction to change the distance between the upper arm and the lower arm. The upper arm comprises upper rollers arranged along an arm main body and each of the upper rollers is parallel with a horizontal direction. The lower arm comprises lower rollers arranged along an arm main body and each of the lower rollers is parallel with a horizontal direction. The continuous sheet is held in contact with the upper rollers and the lower rollers alternately to repeatedly travel between the upper arm and the lower arm, and the distance changing mechanism comprises: a motion transmitting mechanism mechanically coupling the upper arm with the lower arm to synchronize movement of the upper arm with movement of the lower arm; and an actuator for performing at least one of an action to move the upper arm and the lower arm away from each other and an action to move the upper arm and the lower arm close to each other. 
     In the present invention, it is possible to downsize the actuator in the accumulating apparatus. 
     According to a preferred embodiment of the present invention, the upper arm and the lower arm are swung up and down, and the motion transmitting mechanism is a plurality of gears. With this arrangement, the structure of the motion transmitting mechanism can be simplified. 
     In this case, more preferably, the motion transmitting mechanism comprises: an upper gear fixed to the upper arm; and a lower gear fixed to the lower arm and engaged with the upper gear. 
     According to another preferred embodiment of the present invention, in a state where the continuous sheet is removed from the upper arm and the lower arm, the upper arm and the lower arm are balanced at constant positions. It is therefore possible to prevent the continuous sheet from being overloaded. 
     Another accumulating apparatus according to the present invention comprises: an upper arm and a lower arm; and a motion transmitting mechanism mechanically coupling the upper arm with the lower arm, when one arm of the upper arm and the lower arm is moved with respect to a vertical direction, the motion transmitting mechanism simultaneously moves the other arm toward an opposite direction with respect to the vertical direction. The upper arm comprises upper rollers arranged along an arm main body and each of the upper rollers is parallel with a horizontal direction. The lower arm comprises lower rollers arranged along an arm main body and each of the lower rollers is parallel with a horizontal direction. The continuous sheet is held in contact with the upper rollers and the lower rollers alternately to repeatedly travel between the upper arm and the lower arm, and in a state where the continuous sheet is removed from the upper arm and the lower arm, the upper arm and the lower arm are moved away from each other. It is therefore possible to omit an actuator in the accumulating apparatus. 
     These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view showing a part of a manufacturing system of absorbent product in accordance with a first preferred embodiment; 
         FIG. 2  is a view showing an accumulating apparatus in normal operation; 
         FIG. 3  is a view showing an accumulating apparatus of comparative example; 
         FIG. 4  is a view showing an accumulating apparatus in accordance with a second preferred embodiment; 
         FIG. 5  is a view showing another example of an accumulating apparatus; 
         FIG. 6  is a view showing still another example of an accumulating apparatus. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a view showing a part of a manufacturing system  1  of absorbent product in accordance with a first preferred embodiment of the present invention. The manufacturing system  1  shown in  FIG. 1  has a supplying apparatus  2  for drawing continuous sheet  9  from a wound roll  90  where the continuous sheet  9  of nonwoven fabric is wound like a roll, a manufacturing apparatus  3  for sequentially applying processes to each portion of the continuous sheet  9  to manufacture absorbent products (finished products or parts) such as disposable diapers, and an accumulating apparatus  4  (it is also called as an accumulation dancer) located between the supplying apparatus  2  and the manufacturing apparatus  3 . The supplying apparatus  2  and the accumulating apparatus  4  are supported by a base part  11 . The accumulating apparatus  4  is for accumulating the continuous sheet  9  supplied from the upstream supplying apparatus  2  while continuously feeding the continuous sheet  9  to a downstream manufacturing apparatus  3 . In  FIG. 1 , two horizontal directions orthogonal to each other are shown as the X direction and the Y direction, and a vertical direction (i.e., a direction of gravitational force) orthogonal to the X direction and the Y direction is shown as the Z direction. In  FIG. 1 , only a part of the manufacturing apparatus  3  is illustrated. 
     The supplying apparatus  2  has two shaft parts  21 ,  22  each holding one wound roll  90 , and each shaft part  21 ,  22  parallel with the X direction is rotatably supported by the base part  11 . The shaft parts  21 ,  22  are connected with a motor (not shown), and the wound roll  90  can be rotated together with the shaft parts  21 ,  22  by driving the motor, to draw the continuous sheet  9  from the wound roll  90 . There may be a case where the continuous sheet  9  can be drawn from each wound roll  90  by a rotating belt which is in contact with the continuous sheet  9  or the like. 
     In the supplying apparatus  2 , only the continuous sheet  9  drawn from one wound roll  90  is supplied to the accumulating apparatus  4  through a plurality of rollers  23  that are parallel with the X direction (some rollers are denoted by reference signs  23   a .). The plurality of rollers  23  are rotatably supported by the base part  11 . Hereinafter the wound roll  90  from which the continuous sheet  9  is drawn to be supplied to the accumulating apparatus  4  (in  FIG. 1 , the left wound roll  90 ) is referred to as a “current wound roll  90 ”. 
     Cutting parts  24  are provided between two rollers (in  FIG. 1 , they are denoted by reference signs  23   a ) located in the vicinities of respective shaft parts  21 ,  22 . In each cutting part  24 , cutting of the continuous sheet  9  can be achieved by moving a cutter in the Z direction. An after-mentioned splicing part  25  is provided downstream of the two rollers  23   a  (i.e., on the downstream side in a moving direction of portions of the continuous sheet  9 ). 
     The accumulating apparatus  4  has an upper arm  51  located at the upper side ((+Z) side) in the vertical direction, a lower arm  52  located at the lower side ((−Z) side) in the vertical direction, and a distance changing mechanism  6  for changing a distance (i.e., gap distance) between the upper arm  51  and the lower arm  52 . The upper arm  51  has a long arm main body  512  and a plurality of upper rollers  511  arranged along the arm main body  512 . The arm main body  512  has two supporting rods  513  each extending in a direction orthogonal to the X direction, and the two supporting rods  513  are arranged in the X direction. The plurality of upper rollers  511 , parallel with the X direction, are rotatably supported between the two supporting rods  513  parallel with each other. In a similar fashion to the upper arm  51 , the lower arm  52  has a long arm main body  522  and a plurality of lower rollers  521  arranged along the arm main body  522 , and the plurality of lower rollers  521 , parallel with the X direction, are rotatably supported between two supporting rods  523  of the arm main body  522  which are parallel with each other. In the accumulating apparatus  4 , the continuous sheet  9  supplied from the upstream supplying part  2  is held in contact with the upper rollers  511  and the lower rollers  521  alternately from the (−Y) side toward the (+Y) direction, to repeatedly travel between the upper arm  51  and the lower arm  52  (i.e., to have multiple turns therebetween) and to be conveyed. 
     The distance changing mechanism  6  has an upper gear  61  fixed to an end of the arm main body  512  of the upper arm  51  and a lower gear  62  fixed to an end of the arm main body  522  of the lower arm  52 . The upper gear  61  and the lower gear  62  are rotatably supported by the base part  11 , and the upper arm  51  and the lower arm  52  can be swung up and down in the vertical direction (the Z direction) with respect to the upper gear  61  and the lower gear  62  (around the gears), respectively. The upper gear  61  and the lower gear  62  are engaged with each other, and in the present embodiment, the upper gear  61  and the lower gear  62  have the same shape (i.e., both have the same diameter, the same number of gear teeth and the like). Thus, when the lower arm  52  is rotated clockwise or counterclockwise around the lower gear  62  by a predetermined angle, the upper arm  51  is rotated counterclockwise or clockwise around the upper gear  61  by the same angle. In other words, the upper arm  51  and the lower arm  52  are simultaneously moved by the same distance in opposite directions with respect to the vertical direction. With respect to each position in the Y direction, the upper arm  51  and the lower arm  52  are moved simultaneously by the same distance toward respective directions opposite to each other. 
     As above, in the distance changing mechanism  6  shown in  FIG. 1 , the upper gear  61  and the lower gear  62 , which function as a motion transmitting mechanism  60 , mechanically couple the upper arm  51  with the lower arm  52  to synchronize movement of the upper arm  51  with movement of the lower arm  52 . In the present embodiment, the upper gear  61  and the lower gear  62  have the same shape, the amount of torque exerted by the weight of the upper arm  51  on the upper gear  61  is almost equal to the amount of torque the weight of the lower arm  52  exerts on the lower gear  62 , and therefore if supposing a state where the continuous sheet  9  is removed from the upper arm  51  and the lower arm  52 , the upper arm  51  and the lower arm  52  are balanced at constant positions (exactly, tangential forces between the upper gear  61  and the lower gear  62  are balanced and positions of the both arms are not changed). 
     The distance changing mechanism  6  further has an air cylinder  63 , and an end of a piston part  631  of the air cylinder  63  is rotatably attached, through a pin  641 , to a portion of the arm main body  522  in the lower arm  52  which is positioned in the vicinity of the lower gear  62 . Also a main body part (cylinder part)  632  of the air cylinder  63  is rotatably supported through a pin  642  by the base part  11 . With the above structure, the air cylinder  63 , which is an actuator, can perform an action to move the upper arm  51  and the lower arm  52  away from each other and an action to move the upper arm  51  and the lower arm  52  close to each other (i.e., it can perform an action to distance the arms from each other and an action to bring the arms close to each other). The actuator may be another fluid cylinder for moving a piston part by another kind of fluid (for example, oil) other than air. 
     In normal operation of the accumulating apparatus  4 , in a state where the upper arm  51  and the lower arm  52  are close to each other in the Z direction as shown in  FIG. 2 , the continuous sheet  9  supplied from the supplying apparatus  2  located upstream is continuously fed to the downstream manufacturing apparatus  3  (see  FIG. 1 ). In fact, the continuous sheet  9  is conveyed at a constant conveying speed in the manufacturing apparatus  3 , and a supplying speed (i.e., a length of the continuous sheet  9  supplied per unit time) of the continuous sheet  9  is appropriately controlled in the supplying apparatus  2  so that a tension of the continuous sheet  9  positioned in the manufacturing apparatus  3  is kept constant. 
     When the remaining amount of the continuous sheet  9  in the current wound roll  90  becomes low, the lower arm  52  is gradually moved downward (toward the (−Z) direction) by the air cylinder  63  as shown in  FIG. 2 . The upper arm  51  is simultaneously moved in a direction that is opposite to the moving direction of the lower arm  52  (i.e., upward) by the upper gear  61  and the lower gear  62  which are engaged (meshed) with each other, and with respect to the Z direction, the distance between the upper arm  51  and the lower arm  52  (the distance between the upper rollers  511  and the lower rollers  521 ) increases. Therefore, the upper arm  51  and the lower arm  52  are located at positions shown in  FIG. 1  where both are away from each other. At this time, since the supplying speed of the continuous sheet  9  is temporarily increased than that in the normal operation in the supplying apparatus  2 , the feeding speed of the continuous sheet  9  to the downstream manufacturing apparatus  3  and the tension (tensile force) of the continuous sheet  9  are kept constant in the accumulating apparatus  4  while the upper arm  51  and the lower arm  52  are moved away from each other. 
     Subsequently, the supplying apparatus  2  of  FIG. 1  stops supplying the continuous sheet  9  from the current wound roll  90  (the left wound roll  90  in  FIG. 1 ). Also, the lower arm  52  is gradually moved upward (toward the (+Z) direction) by the air cylinder  63 , and with this, the upper arm  51  is moved downward to gradually decrease the distance between the upper arm  51  and the lower arm  52  as shown by the double-dashed lines in  FIG. 1 . Therefore, the feeding speed of the continuous sheet  9  to the downstream manufacturing apparatus  3  and the tension of the continuous sheet  9  are kept constant in the accumulating apparatus  4 . 
     In the supplying apparatus  2 , an end of continuous sheet  9  in the other wound roll  90  (the right wound roll  90  in  FIG. 1 ) is led to the splicing part  25 , and the end of the continuous sheet  9  is spliced (joined) onto continuous sheet  9  of the current wound roll  90  with kraft adhesive tape or the like in the splicing part  25  while stopping supplying the continuous sheet  9  from the current wound roll  90 . And the continuous sheet  9  is cut off from the current wound roll  90  by the cutting part  24  near the current wound roll  90 , and the current wound roll  90  from which continuous sheet  9  is drawn is switched to the right wound roll  90  in  FIG. 1 . The process where the current continuous sheet  9  is spliced to the continuous sheet  9  of another wound roll  90  while stopping movement of the current continuous sheet  9 , is referred to as zero-splice. The splicing of the continuous sheets  9  may be performed by another technique such as heat bonding. A product manufactured with the spliced portion (i.e., a portion on which the kraft adhesive tape is attached) in the manufacturing apparatus  3  is discarded. 
     In the accumulating apparatus  4 , after completion of switching of the current wound roll  90 , the upper arm  51  and the lower arm  52  reach positions in the normal operation shown in  FIG. 2 . At almost the same time, movement of the upper arm  51  and the lower arm  52  is stopped and the supplying apparatus  2  of  FIG. 1  starts (restarts) to supply the continuous sheet  9  from the current wound roll  90 . 
     The wound roll  90  cut by the cutting part  24  (i.e., the wound roll  90  where the remaining amount of the continuous sheet  9  is low) is replaced with a new wound roll  90  (shown by the double-dashed line in  FIG. 1 ). When the remaining amount of the continuous sheet  9  in the current wound roll  90  becomes low, the above process is performed to switch the current wound roll  90  while continuously feeding the continuous sheet  9  to the manufacturing apparatus  3 . In the normal operation, the upper arm  51  and the lower arm  52  may be located at the positions shown in  FIG. 1  where both are away from each other. 
       FIG. 3  is a view showing an accumulating apparatus  91  of comparative example. In the accumulating apparatus  91  of comparative example, structure of an upper arm  911  and a lower arm  912  is same as that of the upper arm  51  and the lower arm  52  of  FIG. 1 , however the upper arm  911  is fixed on a base part and an end  9121  of the lower arm  912  is rotatably supported by the base part. In the accumulating apparatus  91  of a comparative example, when decreasing a distance between the upper arm  911  and the lower arm  912 , the lower arm  912  is moved (rotated) upward by an air cylinder  913 . However, since the weight of the lower arm  912  having a plurality of rollers is large, it is necessary to use the air cylinder  913  whose bore diameter or the like is large, thereby increasing the manufacturing cost of the accumulating apparatus  91 . When increasing the distance between the upper arm  911  and the lower arm  912 , it is thought that the lower arm  52  is moved downward by its own weight. However, in this case, the continuous sheet  9  is overloaded (applied with an excessive load). As shown by the double-dashed lines in  FIG. 3 , by providing a weight  914  to a supporting point of the lower arm  912  so as to be opposite to the lower arm  912 , influence of the weight of the lower arm  912  can be reduced in movement of the lower arm  912  in the up-down direction. However, in this case, the accumulating apparatus  91  becomes large in size. 
     Correspondingly, in the accumulating apparatus  4  shown in  FIG. 1 , since the upper gear  61  and the lower gear  62  are engaged with each other, it is possible to simultaneously move the upper arm  51  and the lower arm  52  opposite to each other with respect to the vertical direction. Therefore, when moving the lower arm  52  in the vertical direction, influence of the weight of the lower arm  52  is canceled (decreased) by the weight of the upper arm  51 . Thus, the force necessary to move the lower arm  52  upward can be reduced without providing the large weight  914  like the accumulating apparatus  91  of the comparative example. As a result, the air cylinder  63  for changing the distance between the upper arm  51  and the lower arm  52  can be downsized and the manufacturing cost of the accumulating apparatus  4  can be reduced. Also the weight of the lower arm  52  does not apply an excessively large load to the continuous sheet  9  unlike the case of the comparative example. 
     In a state of the accumulating apparatus  4  where the continuous sheet  9  is removed from the upper arm  51  and the lower arm  52 , the upper arm  51  and the lower arm  52  are balanced at constant positions, and therefore the continuous sheet  9  can be further prevented from being overloaded by the weight of the lower arm  52 . In addition, since the distance between the upper arm  51  and the lower arm  52  can be changed by a smaller force, the air cylinder  63  can be further downsized. Even if the continuous sheet  9  is removed from the accumulating apparatus  4  for maintenance, both arms can be positioned (stay) at desired positions. 
       FIG. 4  is a view showing an accumulating apparatus  4   a  in accordance with a second preferred embodiment of the present invention. In the accumulating apparatus  4   a  shown in  FIG. 4 , the air cylinder  63  in the accumulating apparatus  4  of  FIG. 1  is omitted and a small weight  524  is provided to the lower arm  52 . The other constituent parts of the accumulating apparatus  4   a  are the same as those of the accumulating apparatus  4  shown in  FIG. 1 , and parts corresponding to respective parts of the accumulating apparatus  4  are denoted by the same reference signs. 
     In the accumulating apparatus  4   a , the upper gear  61  and the lower gear  62  have the same shape, and the amount of torque exerted on the lower gear  62  by the weight of the lower arm  52  is larger than the amount of torque exerted on the upper gear  61  by the weight of the upper arm  51 . Thus, in a state where the continuous sheet  9  has just been removed from the upper arm  51  and the lower arm  52  (i.e., in a period from the time when the continuous sheet  9  is removed to the time when movement of the arms is stopped), the lower arm  52  is moved downward (i.e., toward the (−Z) direction) with respect to the vertical direction and the upper arm  51  is moved upward. 
     In normal operation of the accumulating apparatus  4   a , the continuous sheet  9  supplied from the upstream supplying apparatus  2  is continuously fed to the downstream manufacturing apparatus  3  in a state where the upper arm  51  and the lower arm  52  are close to each other as shown by double-dashed lines in  FIG. 4 . At this time, since the supplying speed of the continuous sheet  9  by the supplying apparatus  2  is equal to a feeding speed of the continuous sheet  9  toward the manufacturing apparatus  3 , the upper arm  51  and the lower arm  52  in the accumulating apparatus  4   a  are almost maintained at the positions shown by the double-dashed lines in  FIG. 4 . In other words, the upper arm  51  and the lower arm  52  are held at the above positions by the continuous sheet  9 . 
     When a remaining amount of the continuous sheet  9  in the current wound roll  90  located left in  FIG. 4  becomes low, the supplying speed of the continuous sheet  9  in the supplying apparatus  2  is temporarily made higher than that in the normal operation. Therefore, an amount (length) of the continuous sheet  9  supplied to the accumulating apparatus  4   a  per unit time increases, the lower arm  52  is moved downward in the vertical direction by the own weight of the lower arm  52 , and this is accompanied by upward movement of the upper arm  51 . Thus, in the accumulating apparatus  4   a , the upper arm  51  and the lower arm  52  are located at positions away from each other as shown in  FIG. 4  (the positions are shown by solid lines.) while the feeding speed of the continuous sheet  9  to the downstream manufacturing apparatus  3  is kept constant. 
     Subsequently, the supplying apparatus  2  stops supplying the continuous sheet  9  from the current wound roll  90 . The manufacturing apparatus  3  keeps drawing the continuous sheet  9  accumulated between the upper arm  51  and the lower arm  52  in the accumulating apparatus  4   a , and with this, a distance between the upper arm  51  and the lower arm  52  gradually decreases. As above, in the accumulating apparatus  4   a , supply of the continuous sheet  9  from the upstream supplying apparatus  2  is stopped while the feeding speed of the continuous sheet  9  to the downstream manufacturing apparatus  3  is kept constant. In a period when the supplying apparatus  2  stops supplying the continuous sheet  9 , current wound roll  90  from which continuous sheet  9  is drawn is switched to the right wound roll  90  in  FIG. 4 , in a similar fashion to the above first preferred embodiment. 
     After completion of switching of current wound roll  90 , at almost the same time when the upper arm  51  and the lower arm  52  reach the positions in the normal operation shown by the chain double-dashed lines in  FIG. 4 , supply of the continuous sheet  9  from the current wound roll  90  is started by the supplying apparatus  2 . Therefore, movement of the upper arm  51  and the lower arm  52  is stopped, and the upper arm  51  and the lower arm  52  keep the positions in the normal operation. 
     As described above, in the accumulating apparatus  4   a  shown in  FIG. 4 , by engaging the upper gear  61  fixed to the upper arm  51  with the lower gear  62  fixed to the lower arm  52 , a motion transmitting mechanism  60  is constructed. When one arm of the upper arm  51  and the lower arm  52  is moved with respect to the vertical direction, the motion transmitting mechanism  60  simultaneously moves the other arm toward an opposite direction with respect to the vertical direction. In addition, the amount of torque exerted on the lower gear  62  by the weight of the lower arm  52  is lager than the amount of torque exerted on the upper gear  61  by the weight of the upper arm  51 , and therefore in a state where the continuous sheet  9  is removed from the upper arm  51  and the lower arm  52 , the upper arm  51  and the lower arm  52  are moved away from each other (i.e., moved toward directions away from each other). Thus, by controlling the supplying speed of the continuous sheet  9  in the supplying apparatus  2 , the distance between the upper arm  51  and the lower arm  52  can be changed without providing the air cylinder  63  of the accumulating apparatus  4  in  FIG. 1 . As the result, the feeding speed of the continuous sheet  9  can be kept constant for a period when supply of the continuous sheet  9  is stopped, while the air cylinder  63  is omitted. Since the weight  524  is small to be able to swing the arm by a small force, the continuous sheet  9  is prevented from being applied with an excessively large tension by the motion transmitting mechanism  60  and the weight  524 . 
     Though the preferred embodiments of the present invention have been discussed above, the present invention is not limited to the above-discussed preferred embodiments, but allows various variations. 
     In the above first and second preferred embodiments, the supplying apparatus  2  does not necessarily stop supplying the continuous sheet  9  when switching the current wound roll  90 . Switching of current wound roll  90  may be performed while a speed of conveying the continuous sheet  9  in the supplying apparatus  2  (the speed is a supplying speed.) is made lower than a speed in normal operation. In the accumulating apparatus  4 ,  4   a , even if the supplying speed of the continuous sheet  9  from the supplying apparatus  2  becomes lower than that in normal operation, the feeding speed of the continuous sheet  9  can be kept constant (i.e., can be maintained at the same speed as the normal operation) by gradually bringing the upper arm  51  and the lower arm  52 , which are away from each other, close to each other. 
     In the accumulating apparatus  4 ,  4   a  shown in  FIGS. 1 and 4 , since the motion transmitting mechanism  60  is implemented by the upper gear  61  and the lower gear  62 , structure of the motion transmitting mechanism  60  can be simplified. However, the upper gear  61  and the lower gear  62  may be mechanically coupled with each other through another gear(s) (in other words, the upper gear  61  and the lower gear  62  may be engaged with each other indirectly.). Since the motion transmitting mechanism is achieved by a plurality of gears (toothed gears), the structure of the motion transmitting mechanism can be simplified. Shapes of the plurality of gears (diameter, the number of gear teeth and so on) may be different from each other. The weight  524  in  FIG. 4  may be omitted by making the number of gear teeth of the lower gear  62  lower than the number of gear teeth of the upper gear  61  (by making a diameter of the lower gear  62  smaller than a diameter of the upper gear  61 ). 
     As shown in  FIG. 5 , there may be a case where a rack  651  extending in the Z direction is fixed to a (+Y) side end portion of the upper arm  51 , a rack  652  extending in the Z direction is fixed to a (+Y) side end portion of the lower arm  52 , and a gear (pinion)  653  engaged with the both rack  651  and rack  652  is provided between the both racks  651 ,  652  to construct a motion transmitting mechanism  60   a  which can simultaneously move the upper arm  51  and the lower arm  52  opposite to each other with respect to the vertical direction (Z direction). Actually, a guide to guide movement of each rack  651 ,  652  is provided. 
     Furthermore, as shown in  FIG. 6 , there may be a case where a slider  662  supported by a guide  661  (only an outer shape is drawn by broken lines in  FIG. 6 .) movably in the Y direction is provided and link members  663 ,  664  in each of which one end is rotatably coupled with the slider  662  and the other end is rotatably coupled with an approximately middle portion of arm main body  512 ,  522  are provided, to achieve a motion transmitting mechanism  60   b  for synchronizing movement of the upper arm  51  with movement of the lower arm  52 . 
     As above, when one arm of the upper arm  51  and the lower arm  52  is moved with respect to the vertical direction, a motion transmitting mechanism simultaneously moves the other arm toward an opposite direction with respect to the vertical direction (i.e., synchronizes movement of the upper arm  51  with movement of the lower arm  52 ) by mechanically coupling the upper arm  51  with the lower arm  52 , and such a motion transmitting mechanism may be implemented by combination of various mechanical elements such as gear, rack, link mechanism, chain, belt (the same applies to the accumulating apparatus  4   a  shown in  FIG. 4 .). 
     In the accumulating apparatus  4  of  FIG. 1  having the air cylinder  63 , the amount of torque exerted on the upper gear  61  by the weight of the upper arm  51  may be made lager than the amount of torque exerted on the lower gear  62  by the weight of the lower arm  52  (in the motion transmitting mechanism  60   a  shown in  FIG. 5 , the weight of the upper arm  51  is made larger than the weight of the lower arm  52 .). In this case, the upper arm  51  and the lower arm  52  can be brought close to each other without using the air cylinder  63  (note that a spacer is provided between the upper arm  51  and the lower arm  52  to keep their positions in normal operation.), and the air cylinder  63  performs an action to move the upper arm  51  and the lower arm  52  away from each other. On the other hand, the amount of torque exerted on the lower gear  62  by the weight of the lower arm  52  may be made lager than the amount of torque exerted on the upper gear  61  by the weight of the upper arm  51  (in the motion transmitting mechanism  60   a  shown in  FIG. 5 , the weight of the lower arm  52  is made larger than the weight of the upper arm  51 .). In this case, by increase of the supplying speed of the continuous sheet  9  in the supplying apparatus  2 , the upper arm  51  and the lower arm  52  can be brought away from each other without using the air cylinder  63 , and the air cylinder  63  performs an action to move the upper arm  51  and the lower arm  52  close to each other. As above, the air cylinder  63  which is an actuator has only to perform at least one of an action to move the upper arm  51  and the lower arm  52  away from each other and an action to move the upper arm  51  and the lower arm  52  close to each other. 
     In a certain design of the accumulating apparatus  4 ,  4   a , an actuator may be implemented by a driving mechanism having a motor, a solenoid or the like. 
     It is only necessary that the number of rollers (upper rollers  511  or lower rollers  521 ) provided in each of the upper arm  51  and the lower arm  52  is two or more, and therefore the accumulating apparatus  4 ,  4   a  can accumulate a sufficient length of the continuous sheet  9 . 
     The accumulating apparatus  4 ,  4   a  for accumulating continuous sheet supplied from an upstream apparatus while continuously feeding the continuous sheet to a downstream apparatus may be used for various applications treating continuous sheet (it may be formed of material other than nonwoven fabric), other than manufacturing of absorbent product with use of the continuous sheet  9  of nonwoven fabric. 
     The constituent elements of above-discussed preferred embodiments and modified examples may be appropriately combined with one another, as long as they are not mutually exclusive. 
     While the invention has been shown and described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is therefore understood that numerous modifications and variations can be devised without departing from the scope of the invention. This application claims priority benefit under 35 U.S.C. Section 119 of Japanese Patent Application No. 2010-275875 filed in the Japan Patent Office on Dec. 10, 2010, the entire disclosure of which is incorporated herein by reference. 
     REFERENCE SIGNS LIST 
     
         
         
           
               2  supplying apparatus 
               3  manufacturing apparatus 
               4 ,  4   a  accumulating apparatus 
               6  distance changing mechanism 
               9  continuous sheet 
               51  upper arm 
               52  lower arm 
               60 ,  60   a ,  60   b  motion transmitting mechanism 
               61  upper gear 
               62  lower gear 
               63  air cylinder 
               511  upper roller 
               512 ,  522  arm main body 
               521  lower roller