Patent Publication Number: US-2023158723-A1

Title: Injection molding system

Description:
TECHNICAL FIELD 
     The present invention relates to an injection molding system. 
     BACKGROUND ART 
     There has been proposed an injection molding system including an injection molding machine having a mold clamping device that opens and closes a mold, and a working device that performs a task of taking out a molded product from the mold. JP H06-155519 A discloses an example thereof. 
     SUMMARY OF THE INVENTION 
     JP H06-155519 A discloses a configuration in which a robot for performing a taking-out task is installed on a side of an injection molding machine. This configuration is difficult to realize in a case where an installation space for the robot cannot be secured on a side of the injection molding machine. 
     Further, the robot disclosed in JP H06-155519 A is installed on an installation pedestal on the side of the mold. In this configuration, the installation pedestal and the robot hinder an operator from performing tasks or operations around the mold. This is not preferable from the viewpoint of workability of the operator. 
      An object of the present invention is to provide an injection molding system which is advantageous for installation in a place where space is limited, and which improves the workability of an operator with respect to a mold. 
     An aspect of the present invention is an injection molding system including: an injection molding machine including a mold clamping device configured to open and close a mold and a machine base configured to support the mold clamping device from below; a working device that is provided under the mold clamping device and is configured to perform at least one of a task of taking out a molded product from the mold or a task of inserting an insert into the mold; and a guide rail configured to retreat the working device from under the mold, in a location under the mold clamping device. 
     According to the present invention, an injection molding system is provided which is advantageous for installation in a place where space is limited, and which improves workability of an operator with respect to a mold. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a configuration diagram of an injection molding system according to an embodiment of the present invention; 
         FIG.  2    is a schematic configuration diagram of a control device according to the embodiment; 
         FIG.  3    is a view for explaining a working position; 
         FIG.  4    is a diagram for explaining a retreated position; 
         FIG.  5    is a flow chart illustrating the flow of a method of controlling the injection molding system of the embodiment; 
         FIG.  6    is a configuration diagram of an injection molding system according to a first modification; 
         FIG.  7    is a configuration diagram of an injection molding system according to a second modification; 
         FIG.  8    is a view for explaining a first position (lower position) in a case where a working device performs a task of taking out a molded product from a mold; 
         FIG.  9    is a view for explaining a second position in a case where the working device performs a task of placing the molded product taken out from the mold at a predetermined position; 
         FIG.  10    is a configuration diagram of an injection molding system according to a tenth modification; 
         FIG.  11    is a first view for explaining an injection molding system according to an eleventh modification; 
         FIG.  12    is a second view for explaining the injection molding system of the eleventh modification; 
         FIG.  13    is a configuration diagram of an injection molding system according to a twelfth modification; 
         FIG.  14    is a first view of the injection molding system of  FIG.  13    viewed from an opening direction side of the injection molding machine; 
         FIG.  15    is a second view of the injection molding system of  FIG.  13    viewed from the opening direction side of the injection molding machine; 
         FIG.  16    is a configuration diagram of an injection molding system according to a thirteenth modification; and 
         FIG.  17    is a schematic configuration diagram of a centralized control apparatus. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     An injection molding system according to the present invention will be detailed below by describing a preferred embodiment with reference to the accompanying drawings. 
     Embodiments 
       FIG.  1    is a configuration diagram of an injection molding system  10  according to an embodiment of the present invention. 
     The injection molding system  10  includes an injection molding machine  12 , a working device  14 , a guide rail  16 , a servo motor (actuator)  18 , a ball screw mechanism  20 , and a control device  22 . 
     The injection molding machine  12  includes a mold clamping device  26  that opens and closes a mold  24  and a machine base  28  that supports the mold clamping device  26  from below. The injection molding machine  12  further includes an injection device  30  that plasticizes a molding material and injects the molding material into the mold  24 . 
     The mold  24  opens and closes in directions in which the mold clamping device  26  and the injection device  30  face each other. That is, the mold  24  has a fixed mold  24   a  and a movable mold  24   b  that comes into contact with and separates from the fixed mold  24   a . The mold  24  is opened when the fixed mold  24   a  and the movable mold  24   b  are separated from each other, and is closed when the fixed mold  24   a  and the movable mold  24   b  are brought into contact with each other. The movable mold  24   b  is moved by driving of the mold clamping device  26 . 
     The opening direction shown in  FIG.  1    is a moving direction of the movable mold  24   b  when moving away from the fixed mold  24   a . Further, the closing direction is a moving direction of the movable mold  24   b  when approaching the fixed mold  24   a . Hereinafter, the closing direction and the opening direction are also collectively referred to as an opening/closing direction. The opening/closing direction is orthogonal to the direction of gravity (up-down direction in  FIG.  1   ). 
     The working device  14  is a device that performs a task of taking out a molded product from the mold  24  (hereinafter, simply referred to as “taking-out task”). The working device  14  of the present embodiment is a robot having an articulated arm  32  capable of gripping a molded product when performing the taking-out task, that is, an arm robot. However, the working device  14  is not limited to the arm robot, and may perform the taking-out task by using a driving mechanism other than the articulated arm  32 . 
     In the present embodiment, the working device  14  is provided under the mold clamping device  26  (i.e., in a dead space of the machine base  28 ). In this configuration, since the working device  14  is accommodated within the machine base  28 , when installing one injection molding machine  12  and one working device  14 , it is enough to just secure a space for the one injection molding machine  12 . Therefore, the injection molding system  10  of the present embodiment is advantageous for installation in a place where space is limited, compared to a configuration in which the working device  14  is provided on the side (or above) of the injection molding machine  12 . 
     The guide rail  16  is installed under the mold clamping device  26  in order to retract or retreat the working device  14  from under the mold  24 . The guide rail  16  of the present embodiment extends at least between a working position (lower position) P1 and a retracted position or retreated position P2, which will be described later, in parallel to the opening/closing direction of the mold  24  ( FIGS.  3  and  4   ). 
     In the present embodiment, the working device  14  is provided with a slider (guide block)  36  configured to be slidably fitted to the guide rail  16 . Thus, the working device  14  is supported by the guide rail  16  so as to be movable parallel to the opening/closing direction. 
     The servo motor  18  generates a driving force for moving the working device  14  along the guide rail  16 . Since the servo motor  18  generates the driving force, the working device  14  can be moved without being manually pushed by an operator. 
     The servo motor  18  includes a rotary shaft  18   a . The servo motor  18  generates a rotational force by rotation of the rotary shaft  18   a . 
     The ball screw mechanism  20  includes a ball screw  38  and a nut  40 . The ball screw  38  is a screw shaft installed in parallel to the guide rail  16 . The rotary shaft  18   a  of the servo motor  18   is connected to the ball screw  38  so as to be integrally rotatable. The nut  40  is a member that is screw-engaged with the ball screw  38 , and is provided in the working device  14 . 
     Thus, the rotational force of the servo motor  18  is converted into a driving force parallel to the guide rail  16 . Further, the driving force is transmitted to the working device  14 . As a result, in the present embodiment, it is possible to move the working device  14  in the opening/closing direction, which is parallel to the guide rail  16 . The movement of the working device  14  in the opening direction and the movement thereof in the closing direction can be easily switched by changing the rotation direction of the rotary shaft  18   a . 
       FIG.  2    is a schematic configuration diagram of the control device  22  according to the embodiment. 
     The control device  22  is a device that controls movement of the working device  14  along the guide rail  16  by controlling at least the servo motor  18  described above. The control device  22  is equipped with a storage unit  42 , an operation unit  44 , a computation unit  46 , and an amplifier  48 . 
     The storage unit  42  stores information and is configured by hardware such as a RAM (random access memory) and a ROM (read only memory). The storage unit  42  stores a predetermined control program  50 . 
     The control program  50  is a program that can be read and executed by the computation unit  46 . The control program  50  specifies information necessary for controlling the servo motor  18 . 
      In addition, the storage unit  42  stores information (position information  52 ) indicating a working position P1 and a retreated position P2 which are predetermined as positions of the working device  14 . 
       FIG.  3    is a diagram for explaining the working position P1. 
     The working position P1 is a position that is under the mold  24 , and is a predetermined position at which the working device  14  performs the taking-out task. The working device  14  that is at the working position P1 performs tasks in a working space  34  around the mold  24 . The storage unit  42  may store a plurality of different working positions P1 according to the type of the mold  24  and the type of the molded product. 
       FIG.  4    is a diagram for explaining the retreated position P2. 
     The retreated position P2 is a predetermined position that avoids or stays away from the working space  34 . The working device  14  that is at the retreated position P2 stands by on the spot without performing the taking-out task. 
     As shown in  FIG.  4   , the retreated position P2 of the present embodiment is under the mold clamping device  26  supported by the machine base  28 , and is closer to the opening direction side than the above-described working position P1. This reduces the possibility that the working device  14  moved to the retreated position P2 protrudes outside the machine base  28  in the widthwise direction of the machine base  28  (see the left-right direction in  FIG.  14   ) orthogonal to the up-down direction and the opening/closing direction. 
      The operation unit  44  is an interface operated by the operator when the operator wants to move the working device  14 . The operation unit  44  of the present embodiment includes a first push button  44 A that is pushed when the working device  14  is to be moved to the retreated position P2, and a second push button  44 B that is pushed when the working device  14  is to be moved to the working position P1. In this case, the operation performed on the operation unit  44  by the operator is that the operator presses the first push button  44 A or the second push button  44 B. 
     When the first push button  44 A is pushed, the operation unit  44  outputs a signal for moving the working device  14  to the retreated position P 2  to the computation unit  46 , and when the second push button  44 B is pushed, the operation unit  44  outputs a signal for moving the working device  14  to the working position P 1  to the computation unit  46 . 
     The computation unit  46  performs arithmetic processing on information, and is configured by hardware such as a CPU (central processing unit) or a GPU (graphics processing unit). As shown in  FIG.  2   , the computation unit  46  includes a movement control unit  54 . The movement control unit  54  is realized by the computation unit  46  reading and executing the control program  50  in the storage unit  42 . 
     The movement control unit  54  generates a control command for driving the servo motor  18 , and outputs the generated control command to the amplifier  48 . When the operation unit  44  is operated, the movement control unit  54  generates different control commands according to the content of the operation. That is, when the first push button  44 A is pushed, the movement control unit  54  generates a control command for moving the working device  14  to the retreated position P2. When the second push button  44 B is pushed, the movement control unit  54  generates a control command for moving the working device  14  to the working position P1. 
     The amplifier  48  serves to perform drive control of the servo motor  18 , and a control command from the movement control unit  54  is input to the amplifier  48 . The amplifier  48  drives the servo motor  18  based on the input control command. The above is the configuration example of the injection molding system  10  according to the present embodiment. 
       FIG.  5    is a flowchart illustrating a flow of a control method of the injection molding system  10  according to the embodiment. 
     Next, a control method of the injection molding system  10  (hereinafter, simply referred to as “control method”) will be described. As a premise, it is assumed that both operation of the injection molding machine  12  and operation of the working device  14  are stopped. 
     The control method includes an operation determination step S 1 , a retreat command step S 2 , a retreat movement step S 3 , a return command step S 4 , and a return movement step S 5 . 
     The operation determination step S 1  is a step of determining which one of the first push button  44 A and the second push button  44 B has been pushed at the time of operating of the operation unit  44 . This step is executed by, for example, the movement control unit  54  of the computation unit  46 . At this time, the movement control unit  54  may determine whether the signal input from the operation unit  44  to the computation unit  46  is a signal input when the first push button  44 A has been pushed or a signal input when the second push button  44 B has been pushed. 
     When it is determined in the operation determination step S 1  that the first push button  44 A has been pushed, the retreat command step S 2  and the retreat movement step S 3  are executed. 
     The retreat command step S 2  is a step of generating and outputting a control command for moving the working device  14  to the retreated position P2. This step is executed by the movement control unit  54 . The generated control command is input to the amplifier  48 . 
     The retreat movement step S 3  is a step of moving the working device  14  to the retreated position P2. This step is executed by the amplifier  48  driving the servo motor  18  based on the control command. Thus, the working device  14  moves to the retreated position P 2  illustrated in  FIG.  4   . 
     On the other hand, when it is determined in the operation determination step S 1  that the second push button  44 B has been pushed, the return command step S 4  and the return movement step S 5  are executed. 
     The return command step S 4  is a step of generating and outputting a control command for moving the working device  14  to the working position P1. This step is executed by the movement control unit  54 . The generated control command is input to the amplifier  48 . 
     The return movement step S 5  is a step of moving the working device  14  to the working position P1. This step is executed by the amplifier  48  driving the servo motor  18  based on the control command. Accordingly, the working device  14  moves to the working position P1 illustrated in  FIG.  3   . The above is the configuration example of the control method of the injection molding system  10  according to the present embodiment. 
     When the operator performs tasks around the mold  24 , if the working device  14  is located at the working position P1, there is a possibility that the workability of the operator is adversely affected. For example, consider a case where the working device  14  is located at the working position P1 when the operator performs replacement work of the mold  24  or maintenance work of the mold  24 . In this case, the operator cannot use the working space  34  around the mold  24  as the operator wishes when performing his/her work, and has to perform the work while avoiding the working device  14 . 
     In this regard, in the injection molding system  10  of the present embodiment, the working device  14  is moved to the retreated position P2 avoiding the working space  34  around the mold  24  merely by pushing the first push button  44 A. Thus, the operator can use the working space  34  at will when performing his/her work. That is, according to the injection molding system  10  of the present embodiment, workability of an operator is improved. 
     Further, in the injection molding system  10  of the present embodiment, the working device  14  moves to the working position P1, which is positioned under the mold  24 , merely by pushing the second push button  44 B. Thus, the operator can easily move the working device  14  to the working position P1 after finishing the task or work on the mold  24 , 
     As described above, according to the present embodiment, there is provided the injection molding system  10  which is advantageous for installation in a place where space is limited, and improves workability of an operator with respect to the mold  24 . 
     Moreover, the injection molding system  10  of the present embodiment includes the servo motor  18  as an actuator that generates a driving force (rotational force) for moving the working device  14 . The servo motor  18  is a motor having good accuracy of rotation control of the rotary shaft  18   a . Therefore, according to the present embodiment, the position control of the working device  14  is realized with good accuracy. 
     Modifications 
     The embodiment has been described above as one example of the present invention. It is noted that various modifications or improvements are capable of being added to the above-described embodiment. Further, it is clear from the scope of the claims that other modes to which such modifications or improvements have been added can be included within the technical scope of the present invention. 
     Hereinafter, some modified examples according to the embodiment will be specifically described. However, in the following, a description overlapping with the embodiment may be appropriately omitted. 
     Modification 1 
       FIG.  6    is a configuration diagram of an injection molding system  10  according to a first modification. 
     Although not described in the embodiment, the control device  22  may further control the working device  14  and the injection molding machine  12 . As shown in  FIG.  6   , the injection molding system  10  may further include a working control device  56  that controls the working device  14 , and a molding control device  58  that controls the injection molding machine  12 , as separate devices from the control device  22 . 
     Modification 2 
       FIG.  7    is a configuration diagram of an injection molding system  10  according to a second modification. 
     In the embodiment, the servo motor  18  is connected to the ball screw mechanism  20 , and the servo motor  18  is controlled by the control device  22  to move the working device  14 . The configuration of the injection molding system  10  is not limited thereto. For example, as shown in  FIG.  7   , a handle  60  may be provided on the ball screw  38  instead of the servo motor  18 . 
     The operator can move the working device  14  by operating the handle  60 . That is, in the configuration of  FIG.  7   , the operator turns the handle  60  to rotate the ball screw  38 . The nut  40  is linearly moved by the rotation of the ball screw  38  in the same manner as in the embodiment. Therefore, in the present modification, the working device  14  moves in conjunction with the operator turning the handle  60 . 
     According to this modification, the servo motor  18  and the control device  22  can be omitted from the configuration of the injection molding system  10 . Further, the operator can easily move the working device  14  by turning the handle  60 . 
     Modification 3 
     In the embodiment, the operation unit  44  having the first push button  44 A and the second push button  44 B has been described. The number of push buttons included in the operation unit  44  is not limited to this, and may be one. In this case, the movement control unit  54  may generate a control command to move the working device  14  to the retreated position P2 when the push button of the operation unit  44  is pushed once, and generate a control command to move the working device  14  to the working position P1 when the push button is pressed again thereafter. 
     Modification 4 
     The operation unit  44  may include a changeover switch or a changeover lever instead of the first push button  44 A and the second push button  44 B. In this case, the movement control unit  54  may generate a control command for moving the working device  14  to the retreated position P2 and a control command for moving the working device  14  to the working position P1 in accordance with a switching operation performed on a switch or a lever. 
     Modification 5 
     When the working device  14  performs work or a task, the control device  22  may control the servo motor  18  such that the working device  14  moves to the working position P1. When the working device  14  does not perform work or a task, the control device  22  may control the servo motor  18  such that the working device  14  moves to the retreated position P2. 
     Such control of the servo motor  18  can be realized by causing the control device  22  to monitor operation of the working device  14  with reference to, for example, the first modification. Accordingly, since the control device  22  also controls the movement of the working device  14 , it is possible to save even labor of the operator operating the operation unit  44 . 
     Modification 6 
     The tasks performed by the working device  14  are not limited to the task of taking out the molded product. The working device  14  may be a device that performs an insertion task of inserting an insert into the mold  24 , or may be a device that performs both the taking-out task and the insertion task. The working position P1 of the mold  24  when the working device  14  performs the insertion task may be a position different from the working position P1 of the mold  24  when the working device  14  performs the taking-out task. 
     Modification 7 
     In relation to the sixth modification, when the working device  14  performs both the taking-out task and the insertion task, the control device  22  may change the working position P1 in accordance with the task content of the working device  14 . By changing the working position P1 in accordance with the task content of the working device  14 , it is possible to cause the working device  14  to efficiently perform tasks. 
     Such control of the servo motor  18  can be realized by causing the control device  22  to monitor operation of the working device  14  with reference to, for example, the first modification. 
     Modification 8 
       FIG.  8    is a view for explaining the first position (lower position) P1 used in a case where the working device  14  performs the task of taking out the molded product from the mold  24 .  FIG.  9    is a view for explaining a second position P1′ used in a case where the working device  14  performs a task of placing the molded product taken out from the mold  24  at a predetermined position. 
     The storage unit  42  of the control device  22  may store the first position (lower position) P1 used in the case where the working device  14  performs the task of taking out the molded product from the mold  24  and the second position P1′ used in the case where the working device  14  performs the task of placing the taken-out molded product at a predetermined position. The movement control unit  54  of the control device  22  may change the position of the working device  14  in accordance with the task performed by the working device  14  based on the positions stored in the storage unit  42 . Note that the second position P1′ may not be a position under the mold  24 . The predetermined position on which the molded product is placed is, for example, a position on a conveyor  61  for carrying out the molded product. 
     That is, after the molded product has been taken out, it is necessary to place the molded product at a predetermined position. At this time, the position of the working device  14  at which the molded product is easily taken out and the position of the working device  14  at which the molded product is easily placed at a predetermined position may be different from each other. By changing the position of the working device  14  in accordance with the task performed by the working device  14 , it is possible to cause the working device  14  to efficiently perform tasks. 
     Such control of the servo motor  18  can be realized, for example, by causing the control device  22  to monitor what kind of control is performed on the working device  14  by the working control device  56  (see Modification 1). 
     Modification 9 
     Modification 8 can also be applied to a case where the working device  14  performs the task of inserting an insert. That is, in order to insert the insert into the mold  24 , it is necessary for the working device  14  to grip the insert placed at a predetermined position in advance. At this time, the position of the working device  14  where it is easy to grip the insert placed at the predetermined position and the position of the working device  14  where it is easy to insert the gripped insert into the mold  24  may be different from each other. In such a case, the above-described first position (working position P1) may be considered as a position used in a case where the task of inserting the insert into the mold  24  is performed, and the second position P1′ may be considered as a position used in a case where the task of gripping the insert placed at a predetermined position is performed. Accordingly, it is possible to cause the working device  14  to efficiently perform tasks. 
     The predetermined position at which the insert is placed is, for example, a position on the conveyor  61  similar to that shown in  FIGS.  8  and  9   . In the case of this modification, the conveyor  61  is a conveyor for carrying-in an insert. 
     Modification 10 
       FIG.  10    is a configuration diagram of an injection molding system  10  according to a tenth modification. 
     The actuator that generates the driving force for moving the working device  14  is not limited to the servo motor  18 . For example, a power cylinder such as an air cylinder or a hydraulic cylinder, or a linear motor may be used. In this case, the control device  22  may be configured to control the power cylinder or the linear motor. 
      Unlike the servo motor  18 , the power cylinder or the linear motor is a linear actuator  18 ′ that generates linear motion power instead of rotational motion power. When the injection molding system  10  includes the linear actuator  18 ′, the ball screw mechanism  20 , which converts the rotational force into a force acting in a direction parallel to the guide rail  16 , is not particularly necessary. 
     Modification 11 
       FIG.  11    is a first view for explaining an injection molding system  10  according to an eleventh modification.  FIG.  12    is a second view for explaining the injection molding system  10  of Modification  11 . 
     Although not described in the embodiment, in a case where the drive mechanism of the working device  14  is the articulated arm  32  having a plurality of joints  62 , as shown in  FIGS.  11  and  12   , each of the plurality of joints  62  is provided with a joint drive motor  64  for driving the joint  62 . The joint drive motor  64  may be used as an actuator that generates a driving force for moving the working device  14 . 
     That is, by controlling the plurality of joint drive motors  64  included in the articulated arm  32 , it is possible to cause the articulated arm  32  to grip the machine base  28  or the mold clamping device  26  ( FIG.  11   ) and to bend and stretch the articulated arm  32  ( FIG.  12   ). This makes it possible to move the working device  14 . In addition, according to this configuration, the ball screw mechanism  20  described in the embodiment becomes unnecessary. 
     Such movement of the working device  14  can be realized by the control device  22  controlling the articulated arm  32  or by requesting the working control device  56  to control the articulated arm  32 , for example, with reference to Modification 1. 
     By causing the articulated arm  32  to grip a movable portion of the mold clamping device  26 , it is also possible to move the working device  14  along with the movement of the movable portion. The movable portion of the mold clamping device  26  is, for example, a movable platen  65 . The movable platen  65  is a member that moves in the opening/closing direction along with the movable mold  24   b  in order to realize opening and closing of the mold  24 . That is, by causing the articulated arm  32  to grip the movable platen  65  from below, it is possible to move the working device  14  in the opening/closing direction in accordance with the movement of the movable platen  65 . 
     Modification  12   
       FIG.  13    is a configuration diagram of an injection molding system  10  according to a twelfth modification.  FIG.  14    is a first view of the injection molding system  10  of  FIG.  13    viewed from the opening direction side of the injection molding machine  12 . 
     In the embodiment, the injection molding system  10  has been described in which the guide rail  16  extending in parallel to the opening/closing direction is provided to enable the movement of the working device  14  in parallel to the opening/closing direction. The configuration of the injection molding system  10  is not limited thereto. For example, as shown in  FIGS.  13  and  14   , the injection molding system  10  may include a guide rail  16  that extends parallel to the width direction (the left-right direction in  FIG.  14   ) of the machine base  28  orthogonal to the opening/closing direction and the up-down direction. Thus, the working device  14  can be moved parallel to the width direction. 
       FIG.  14    illustrates a state in which the working device  14  is at the working position P1 of the mold  24 . In this state, similarly to the embodiment, the working device  14  performs tasks on the injection molding machine  12  at the working position P1. 
       FIG.  15    is a second view of the injection molding system  10  of  FIG.  13    as viewed from the opening direction side of the injection molding machine  12 . 
       FIG.  15    illustrates a state in which the working device  14  is at the retreated position P2. As shown in  FIG.  15   , the retreated position P2 and the working position P1 are arranged side by side with each other in the width direction of the machine base  28  in the present modification. Also in the present modification, by moving the working device  14  to the retreated position P 2 , the working space  34  for the operator can be secured around the mold  24  including the working position P1. 
     Modification 13 
       FIG.  16    is a configuration diagram of an injection molding system  10  according to a thirteenth modification. 
     As shown in  FIG.  16   , the injection molding system  10  may include a plurality of the configurations illustrated in  FIG.  1   . In this case, the injection molding system  10  may further include a centralized control apparatus  66  to which the plurality of control devices  22  are connected and which collectively sets (or specifies) at least one of the working position P1 or the retreated position P2 on the plurality of control devices  22  at a time. 
       FIG.  17    is a schematic configuration diagram of the centralized control apparatus  66 . 
     The centralized control apparatus  66  is an electronic device (computer) connected to the plurality of control devices  22  via a network. The centralized control apparatus  66  includes a computation unit  68 , an operation unit  70 , a storage unit  72 , and a display unit  74 . 
     The computation unit  68  is configured by a CPU or a GPU similarly to the computation unit  46  of the control device  22 , and serves for overall control of the centralized control apparatus  66 . 
     The storage unit  72  is configured by a ROM or a RAM similarly to the storage unit  42  of the control device  22 , and appropriately stores programs necessary for control performed by the computation unit  68 , information input by an operator using the operation unit  70 , and the like. 
     The display unit  74  displays information and includes, for example, a liquid crystal screen. Information or the like input by the operator through the operation unit  44  is appropriately displayed on the display unit  74 . 
     The operation unit  70  is an interface operated by an operator to set (or specify) at least one of the working position P1 or the retreated position P2. The operation unit  70  includes, for example, a mouse, a keyboard, or a touch panel provided on the screen of the display unit  74 . 
     The computation unit  68  includes a command outputting unit  76 . The command outputting unit  76  outputs at least one of the working position P1 or the retreated position P2 set by the operator to the plurality of control devices  22  connected to the centralized control apparatus  66 . When moving the working device  14 , each of the plurality of control devices  22  controls the motor ( 18 ,  18 ′,  64 ), which is the control target of the control device  22 , based on the information input from the centralized control apparatus  66 . The motor in this case is preferably a servo motor from the viewpoint of control accuracy. 
     According to the present modification, it is possible to collectively set at least one of the working position P1 or the retreated position P2 on the plurality of control devices  22  at a time. Accordingly, it is possible to reduce the time and effort of the work of setting the working position P1 and the retreated position P2 on the plurality of control devices  22 . In addition, it is possible to reduce a possibility that an operation error such as omission of setting of information with respect to any of the plurality of control devices  22  may occur. 
     Modification 14 
     In relation to Modification  13 , one of the plurality of control devices  22  may be used as the centralized control apparatus  66 . That is, the injection molding system  10  may be configured such that, when at least one of the working position P1 or the retreated position P2 is set on one of the plurality of control devices  22 , the setting is also applied to the other control devices  22 . 
     Modification 15 
     The modifications may be appropriately combined within a range in which no technical inconsistencies occur. 
      Inventions That Can Be Obtained From the Embodiment 
     The inventions that can be grasped from the above-described embodiment and the modifications thereof will be described below. 
     The injection molding system ( 10 ) includes: the injection molding machine ( 12 ) including the mold clamping device ( 26 ) configured to open and close the mold ( 24 ) and the machine base ( 28 ) configured to support the mold clamping device ( 26 ) from below; the working device ( 14 ) that is provided under the mold clamping device ( 26 ) and is configured to perform at least one of a task of taking out a molded product from the mold ( 24 ) or a task of inserting the insert into the mold ( 24 ); and the guide rail ( 16 ) configured to retreat the working device ( 14 ) from under the mold ( 24 ), in a location under the mold clamping device ( 26 ). 
     With this configuration, it is possible to provide the injection molding system ( 10 ) which is advantageous for installation in a place where space is limited, and improves workability of an operator with respect to the mold ( 24 ). 
     The guide rail ( 16 ) may be disposed to allow the working device ( 14 ) to move in parallel to the opening/closing direction of the mold ( 24 ). This reduces the possibility that the working device ( 14 ) may protrude outside the machine base ( 28 ) in the width direction of the machine base ( 28 ) even if the working device ( 14 ) is moved to the retreated position (P2). 
     The injection molding system ( 10 ) may further include: the ball screw ( 38 ) installed parallel to the guide rail ( 16 ); the nut ( 40 ) provided in the working device ( 14 ) and configured to be screw-engaged with the ball screw ( 38 ); and the handle ( 60 ) provided on the ball screw ( 38 ) and configured to be operated by an operator to thereby rotate the ball screw ( 38 ). Thus, the operator can move the working device ( 14 ) by operating the handle ( 60 ). 
     The injection molding system ( 10 ) may further include the actuator ( 18 ,  18 ′,  64 ) that generates a driving force for moving the working device ( 14 ) along the guide rail ( 16 ), and the control device ( 22 ) that controls at least the actuator ( 18 ,  18 ′,  64 ). This makes it possible to move the working device ( 14 ) without being manually pushed by the operator. 
     The working device ( 14 ) may include the articulated arm ( 32 ), the actuator ( 64 ) may be provided to drive the articulated arm ( 32 ), and the control device ( 22 ) may control the actuator ( 64 ) to cause the articulated arm ( 32 ) to grip the machine base ( 28 ) or the mold clamping device ( 26 ), and cause the articulated arm ( 32 ) to bend and stretch to move the working device ( 14 ). This makes it possible to move the working device ( 14 ). 
     The control device ( 22 ) may control the actuator ( 18 ,  18 ′,  64 ) in a manner that the working device ( 14 ) moves to the lower position (P1) that is under the mold ( 24 ) or the retreated position (P2) that is away from the mold ( 24 ), in accordance with an operation performed by an operator. Thus, the operator can easily move the working device ( 14 ) to the retreated position (P2) avoiding the position that is under the mold ( 24 ), merely by operating the control device ( 22 ). 
     The control device ( 22 ) may control the actuator ( 18 ,  18 ′,  64 ) in a manner that the working device ( 14 ) is moved to the lower position (P1) that is under the mold ( 24 ), when the working device ( 14 ) performs tasks, and the working device ( 14 ) is moved to the retreated position (P2) that is away from the mold ( 24 ), when the working device ( 14 ) does not perform tasks. This makes it possible to eliminate even the time and effort required for the operator to operate the operation unit ( 44 ). 
     The actuator ( 18 ,  18 ′,  64 ) may be a motor, and the control device ( 22 ) may change the lower position (P1) in accordance with the task content of the working device ( 14 ). This makes it possible to cause the working device ( 14 ) to perform tasks efficiently. 
     The actuator ( 18 ,  18 ′,  64 ) may be a motor. Further, the control device ( 22 ) may include the storage unit ( 42 ) configured to store the lower position (P1) and the retreated position (P2) according to the type of the molded product molded by using the mold ( 24 ), and the control device ( 22 ) may control the motor in a manner that the working device ( 14 ) moves to the lower position (P1) or the retreated position (P2) according to the mold ( 24 ) attached to the injection molding machine ( 12 ). Thus, the movement of the working device ( 14 ) can be controlled based on the lower position (P1) and the retreated position (P2) stored in the storage unit ( 42 ) . 
     The storage unit ( 42 ) may further store the first lower position (P1) used in a case where the task of taking out the molded product is performed or the task of inserting the insert is performed, and the second position (P1′) used in a case where a task of placing the molded product taken out by the working device ( 14 ) at a predetermined position ( 61 ) is performed or a task of gripping the insert placed at the predetermined position is performed, and the control device ( 22 ) may change the position of the working device ( 14 ) by using the storage unit ( 42 ). This makes it possible to cause the working device ( 14 ) to perform tasks efficiently. 
     The injection molding system ( 10 ) may further include a centralized control apparatus ( 66 ) to which a plurality of the control devices ( 22 ) are connected and that is configured to collectively set at least one of the lower position (P1) or the retreated position (P2) on the plurality of control devices ( 22 ) at a time. With this configuration, it is possible to reduce the time and effort of the task of setting the lower position (P1) and the retreated position (P2) on the plurality of control devices ( 22 ). In addition, it is possible to reduce a possibility that an operational error such as omission of setting of information with respect to any of the plurality of control devices ( 22 ) may occur.