Patent Description:
A machine tool such as a lathe includes a workpiece conveyance device that receives and delivers workpieces from/to a plurality of spindles (workpiece holders) that hold and rotate workpieces to be machined. As an example of the workpiece conveyance device, a configuration having main loaders and relay loaders, the main loaders moving along a rail disposed on a machine tool body and receiving and delivering workpieces from/to spindles of the machine tool body and the relay loaders receiving and delivering the workpieces from/to the main loaders and receiving and delivering the workpieces from/to a workpiece supply stand or a workpiece discharge stand, is known (for example, see Patent Literature <NUM>).

In the aforementioned workpiece conveyance device, since receiving and delivery of the workpiece between the main loader and the relay loader is performed by switching between a chuck receiving the workpiece and a chuck delivering the workpiece, there is a problem in that it takes time to switch between the chucks, and a time required for conveying the workpiece becomes long. Furthermore, for example, in a case where there are a plurality of spindles like a parallel double spindle lathe or the like, if one main loader receives and delivers a workpiece from/to each spindle, a time required for workpiece conveyance becomes long, and workpiece machining efficiency is reduced. Therefore, it is desired to efficiently convey the workpiece when there are a plurality of spindles.

The nearest state of the art regarding the present invention is disclosed in <CIT>. This document already discloses a workpiece conveyance system that receives and delivers workpieces to be machined from/to two workpiece holders that hold the workpieces, comprising a main loader including three main loader chucks that can receive and deliver the workpieces from/to the two workpiece holders.

A rather similar state of the art is also disclosed in <CIT>.

In view of the foregoing, an object of the present invention is to provide a workpiece conveyance system and a machine tool system, by which, even when there are a plurality of workpiece holders such as spindles, it is possible to improve workpiece machining efficiency by efficiently receiving and delivering a workpiece from/to each workpiece holder and shortening a time required for workpiece conveyance.

To solve the above problems, the present invention provides a machine tool system with a workpiece conveyance system according to claim <NUM>, that receives and delivers workpieces from/to n workpiece holders (where n is an integer satisfying n ≥ <NUM>) that hold and rotate workpieces to be machined, including a main loader including n + m main loader chucks (where m is an integer satisfying m ≥ <NUM>) that receive and deliver the workpieces from/to the n workpiece holders or n relay loaders disposed corresponding to the n respective workpiece holders to receive and deliver the workpieces from/to the workpiece holders.

Furthermore, the workpiece conveyance system may include a controller that, when the n main loader chucks hold unmachined workpieces and the m main loader chucks are in an empty state in relation to one of the n workpiece holders, allows the main loader chucks in the empty state to receive a machined workpiece from the one of the workpiece holders and allows the main loader chucks holding the unmachined workpieces to supply the unmachined workpiece to the one of the workpiece holders, and in relation to one of next workpiece holders, allows the main loader chucks previously in the empty state to receive a machined workpiece from the one of the next workpiece holders and allows the main loader chucks holding the unmachined workpieces to supply the unmachined workpiece to the one of the next workpiece holders, the controller receiving the machined workpiece and supplying the unmachined workpiece from/to the one of the workpiece holders repeatedly n times. Furthermore, the relay loaders may each include a relay loader chuck that receives and delivers the workpiece from/to the corresponding workpiece holder, and in the main loader, the main loader chucks may move to a position corresponding to the relay loader chuck and receive and deliver the workpiece from/to the relay loader chuck. Furthermore, one of the relay loaders may have disposed thereon a plurality of the relay loader chucks. Furthermore, the n + m main loader chucks may be disposed in one direction at a predetermined interval, the relay loader chucks may be disposed at the same interval as that between the main loader chucks, and the relay loader chucks may be disposed in parallel with the one direction with the movement of the relay loaders. Furthermore, the workpiece conveyance system may include a controller that performs, in one operation, an operation of delivering the workpieces from the relay loader chucks to the main loader chucks and an operation of delivering the workpieces from the main loader chucks to the relay loader chucks.

Furthermore, the main loader is movable in a direction that is a horizontal direction and is orthogonal to a direction of a rotation axis of the workpiece holders, and the relay loaders are able to turn in a direction around an axis parallel with the rotation axis of the workpiece holders, and may be configured to turn between a first position where any one of the relay loader chucks faces the workpiece holder and a second position where the relay loader chucks can face the n + m main loader chucks. Furthermore, the relay loader chucks and the main loader chucks may be configured to hold the workpieces toward a direction parallel with the rotation axis of the workpiece holders. Furthermore, the main loader chucks may be switched between a state of holding a workpiece toward a direction parallel with the rotation axis of the corresponding workpiece holder and a state of holding a workpiece in a downward direction.

Furthermore, the present invention provides a machine tool system including a machine tool body including a plurality of workpiece holders that hold and rotate workpieces to be machined, a carrying-in part that holds an unmachined workpiece, a carrying-out part that holds a machined workpiece, and the workpiece conveyance system that conveys a workpiece between the workpiece holders and the carrying-in part, or between the workpiece holders and the carrying-out part, or both.

According to the workpiece conveyance system and the machine tool system of the present invention, since the n + m main loader chucks are provided for the n workpiece holders, the main loader does not need to repeat movement between the workpiece holder and the carrying-in part and between the workpiece holder and the carrying-out part for each workpiece holder, and since the main loader can receive and deliver workpieces from/to the n workpiece holders in a short period of time, the efficiency in conveying workpieces is improved, and thus it is possible to improve workpiece machining efficiency. Furthermore, when the aforementioned controller is provided, receiving of a machined workpiece and supplying of an unmachined workpiece from/to one of the workpiece holders can be efficiently performed by the controller. Furthermore, in the case where the workpiece conveyance system has the relay loader including the relay loader chucks disposed corresponding to the n respective workpiece holders to receive and deliver workpieces from/to the workpiece holders, and the main loader chuck moves to a position corresponding to the relay loader chuck and receives and delivers a workpiece from/to the relay loader chuck, since the main loader can move toward another workpiece holder while the relay loader delivers and receives a workpiece from/to the workpiece holder, and the time during which the main loader stops is shortened, the efficiency in conveying workpieces can be improved. Furthermore, when one of relay loaders has disposed thereon a plurality of the relay loader chucks, a plurality of workpieces can be simultaneously received and delivered between the plurality of relay loader chucks of such a relay loader and the n + m main loader chucks of the main loader; for example, while a machined workpiece held by one of the relay loader chucks is delivered to one of the main loader chucks, an unmachined workpiece held by another one of the main loader chucks can be received by another one of the relay loader chucks. As described above, since a plurality of workpieces can be simultaneously received and delivered, a time required for receiving and delivering the workpieces can be shortened, and efficiency in conveying the workpieces can be improved.

Furthermore, when the n + m main loader chucks are disposed in one direction at a predetermined interval, the relay loader chucks are disposed at the same interval as that among the main loader chucks, and the relay loader chucks can be disposed in parallel with the one direction with the movement of the relay loaders, the relay loader chucks and the n + m main loader chucks can be allowed to easily face each other and a plurality of workpieces can be easily received and delivered. Furthermore, when the workpiece conveyance system includes a controller that performs, in one operation, an operation of delivering the workpieces from the relay loader chucks to the main loader chucks and an operation of delivering the workpieces from the main loader chucks to the relay loader chucks, the relay loader and the main loader can be easily operated by the controller. Furthermore, when the main loader is movable in a direction that is a horizontal direction and is orthogonal to a direction of a rotation axis of the workpiece holders, and the relay loaders are able to turn in a direction around an axis parallel with the rotation axis of the workpiece holders, and turn between a first position where any one of the relay loader chucks faces the workpiece holder and a second position where the relay loader chucks can face the n + m main loader chucks, the main loader can efficiently move to the workpiece holders and the relay loader turns between the first position and the second position, so that the relay loader chuck can be allowed to easily face the workpiece holder or the main loader chuck.

Furthermore, in a case where the relay loader chuck and the main loader chuck hold workpieces toward a direction parallel with the rotation axis of the workpiece holders, when the relay loader chuck receives and delivers a workpiece from/to the workpiece holder or the main loader chuck, it is possible to shorten a time required for receiving and delivering the workpiece because it is not necessary to change the orientation of the relay loader chuck or the main loader chuck. Furthermore, when the main loader chucks can be switched between a state of holding a workpiece toward a direction parallel with the rotation axis of the corresponding workpiece holder and a state of holding a workpiece in a downward direction, even though the workpiece is placed in an upward direction, it is possible to hold the workpiece by switching the orientation of the main loader chuck and it is possible to ensure the general usability of the orientation in which the workpiece is placed.

However, the present invention is not limited to the forms illustrated in the drawings. In the drawings, in order to describe the content, the scale is appropriately changed by enlarging or emphasizing a part, for example. In each of the following drawings, directions in the drawings will be described using an XYZ coordinate system. In the XYZ coordinate system, a plane parallel with a horizontal plane is defined as an XZ plane. In the XZ plane, a direction of a spindle <NUM> or the like is denoted as a Z direction and a direction orthogonal to the Z direction is denoted as an X direction. Furthermore, a direction perpendicular to the XZ plane is denoted as a Y direction. Each of the X direction, the Y direction, and the Z direction will be described on the assumption that in the drawings, the arrow direction is a positive (+) direction and a direction opposite to the arrow direction is a negative (-) direction.

A first embodiment will be described with reference to the drawings. <FIG> is a diagram illustrating an example of a workpiece conveyance system <NUM> and a machine tool system <NUM> according to the first embodiment. As illustrated in <FIG>, the machine tool system <NUM> includes a first body (machine tool body) <NUM>, a second body (machine tool body) <NUM>, a carrying-in part <NUM>, a carrying-out part <NUM>, the workpiece conveyance system <NUM>, and a controller <NUM>. The controller <NUM> is a controller of the machine tool system <NUM> and is a controller of the workpiece conveyance system <NUM>. However, the present invention is not limited to one controller <NUM> and the controller of the machine tool system <NUM> and the controller of the workpiece conveyance system <NUM> may also be installed separately.

The first body <NUM> and the second body <NUM>, for example, are parallel double spindle lathes and are disposed in the +Z direction as a front side. The first body <NUM> has spindles (workpiece holders) <NUM> and <NUM>, and a cutting tool holder such as a turret (not illustrated) that holds a cutting tool. The cutting tool holder such as the turret holds a plurality of cutting tools that cut a workpiece W, and one of the cutting tools is selected for use. The two spindles <NUM> and <NUM> are juxtaposed in the X direction. Each of the spindles <NUM> and <NUM> is rotatably supported around the axial line of a rotation axis AX1 parallel with the Z direction by a bearing or the like (not illustrated). Spindle chucks <NUM> and <NUM> are disposed at ends of the spindles <NUM> and <NUM> on the +Z side, respectively. The spindle chucks <NUM> and <NUM> include a plurality of grasping claws 13A and 14A (see <FIG>), and can hold the workpieces W toward the +Z direction by closing the grasping claws 13A and 14A, respectively.

Similar to the first body <NUM>, the second body <NUM> has spindles (workpiece holders) <NUM> and <NUM>, and a cutting tool holder such as a turret (not illustrated) that holds a cutting tool. The cutting tool holder such as the turret holds a plurality of cutting tools that cut the workpiece W, and one of the cutting tools is selected for use. The two spindles <NUM> and <NUM> are juxtaposed in the X direction. Each of the spindles <NUM> and <NUM> is rotatably supported around the axial line of the rotation axis AX1 parallel with the Z direction by a bearing or the like (not illustrated). Similar to the spindles <NUM> and <NUM>, spindle chucks <NUM> and <NUM> are disposed at ends of the spindles <NUM> and <NUM> on the +Z side, respectively. The spindle chucks <NUM> and <NUM> include a plurality of grasping claws 23A and 24A (see <FIG>), and can hold the workpieces W toward the +Z direction by closing the grasping claws 23A and 24A, respectively.

The spindles <NUM> and <NUM> and the spindles <NUM> and <NUM> are parallel with each other, the ends of these spindles <NUM>, <NUM>, <NUM>, and <NUM> on the +Z side are disposed to be aligned in the X direction (spindle chucks <NUM>, <NUM>, <NUM>, and <NUM> are aligned in the X direction). In the present embodiment, the number of spindles of each of the first body <NUM> and the second body <NUM> is <NUM> but is not limited thereto; n spindles (where n is an integer satisfying n ≥ <NUM>) may be disposed, and three or more spindles may be disposed.

The carrying-in part <NUM> allows an unmachined workpiece W to be machined to be placed thereon in the machine tool system <NUM>. The carrying-in part <NUM> has a holding table <NUM> that holds the workpieces W. The holding table <NUM> holds two or more (two in the present embodiment) unmachined workpieces W. A plurality of workpieces W are juxtaposed at an interval d to be described later. The carrying-in part <NUM> is configured to be able to deliver the unmachined workpiece W to a main loader <NUM> to be described later. Details of the carrying-in part <NUM> will be described later.

The carrying-out part <NUM> holds a machined workpiece W machined by the first body <NUM> or the second body <NUM> in the machine tool system <NUM>. The carrying-out part <NUM> has a plurality of (two in the present embodiment) carrying-out chucks <NUM> capable of holding the machined workpiece W. The carrying-out chucks <NUM> are juxtaposed at the interval d to be described later. Each of the carrying-out chucks <NUM> can hold the workpiece W toward the -Z direction. However, the carrying-out part <NUM> is not limited to being provided with the carrying-out chucks <NUM> and, for example, may include a placement table on which the machined workpiece W is simply placed.

The workpiece conveyance system <NUM> has relay loaders <NUM> (relay loaders) and a main loader <NUM> (main loader). The relay loaders <NUM> are disposed corresponding to n respective spindles <NUM> and <NUM> in the first body <NUM> (where n is an integer satisfying n ≥ <NUM>; n = <NUM> in the present embodiment) and are disposed corresponding to n respective spindles <NUM> and <NUM> in the second body <NUM> (where n is an integer satisfying n ≥ <NUM>; n = <NUM> in the present embodiment). In the present embodiment, two relay loaders <NUM> are disposed at two positions of the -X side of the spindle <NUM> and the +X side of the spindle <NUM> in the first body <NUM>, and are disposed at two positions of the -X side of the spindle <NUM> and the +X side of the spindle <NUM> in the second body <NUM>. Hereinafter, when the two relay loaders <NUM> disposed in each of the first body <NUM> and the second body <NUM> are distinguished from each other, the relay loaders <NUM> on the -X side, that is, the relay loaders <NUM> disposed corresponding to the spindles <NUM> and <NUM> are denoted as relay loaders 51a. Furthermore, the relay loaders <NUM> on the +X side, that is, the relay loaders <NUM> disposed corresponding to the spindles <NUM> and <NUM> are denoted as relay loaders 51b.

The relay loader <NUM> has a plurality of (two in the present embodiment) relay loader chucks <NUM>. Hereinafter, when the two relay loader chucks <NUM> are distinguished from each other, the relay loader chuck <NUM> on the -X side is denoted as a relay loader chuck 53a and the relay loader chuck <NUM> on the +X side is denoted as a relay loader chuck 53b. The relay loader chucks <NUM> are disposed at the same interval d as that among a plurality of main loader chucks <NUM> disposed in the main loader <NUM> to be described later.

The number of relay loader chucks <NUM>, which are provided in one relay loader <NUM>, is not limited to <NUM>, and three or more relay loader chucks <NUM> may be provided. When three or more relay loader chucks <NUM> are disposed, the respective relay loader chucks <NUM> are disposed to be aligned in one direction at the predetermined interval d. Each of the relay loader chucks <NUM> includes grasping claws, a sucker, or the like (not illustrated) that hold the workpiece W, and can hold the workpiece W toward the -Z direction, that is, a direction parallel with the rotation axes AX1 of the spindles <NUM>, <NUM>, <NUM>, and <NUM>. The relay loader chuck <NUM> receives and delivers the workpiece W from/to each of the spindles <NUM>, <NUM>, <NUM>, and <NUM>.

Each of the relay loader chucks <NUM> can move back and forth in the -Z direction, and when delivering the workpiece W to the spindle <NUM> or the like, moves in the -Z direction to receive and deliver the workpiece W. However, the present invention is not limited to the case where the relay loader chuck <NUM> moves back and forth in the -Z direction, and the spindle <NUM> or the like may move back and forth in the +Z direction when receiving and delivering the workpiece W. The relay loader chuck <NUM> moves in the -Z direction, so that an unmachined workpiece W is delivered from the relay loader chuck <NUM> to the spindle <NUM> or the like, or a machined workpiece W is received in the relay loader chuck <NUM> from the spindle <NUM> or the like. Details of the relay loader <NUM> will be described later using other drawings.

The main loader <NUM> conveys the workpiece W between the carrying-in part <NUM> and the relay loader <NUM> and between the relay loader <NUM> and the carrying-out part <NUM>. The main loader <NUM> includes a loader head (for example, see a loader head 52B in <FIG>), and the loader head has n + m main loader chucks <NUM> (where m is an integer satisfying m ≥ <NUM>). In the present embodiment, a case where the number of main loader chucks <NUM> is <NUM>, that is, n = <NUM> and m = <NUM> will be described. Hereinafter, when three main loader chucks <NUM> are distinguished from one another, the main loader chuck <NUM> on the most -X side is denoted as a main loader chuck 56a, the main loader chuck <NUM> at the center in the X direction is denoted as a main loader chuck 56b, and the main loader chuck <NUM> on the most +X side is denoted as a main loader chuck 56c.

Each of the main loader chucks <NUM> includes a plurality of grasping claws <NUM> (see <FIG>) that grasp the workpiece W and can hold the workpiece W toward the +Z direction, that is, the direction parallel with the rotation axes AX1 of the spindles <NUM>, <NUM>, <NUM>, and <NUM> by closing the grasping claws <NUM>. The main loader chuck <NUM> receives the workpiece W from the carrying-in part <NUM> or delivers the workpiece W to the carrying-out part <NUM>. The main loader chuck <NUM> can move back and forth in the +Z direction. When receiving the workpiece W from the carrying-in part <NUM> or when delivering the workpiece W to the carrying-out part <NUM>, the main loader chuck <NUM> moves in the +Z direction with respect to the carrying-in part <NUM> or the carrying-out part <NUM>.

Furthermore, the main loader chuck <NUM> receives and delivers the workpiece W from/to the relay loader chuck <NUM>. When receiving and delivering the workpiece W, the main loader chuck <NUM> moves in the +Z direction toward the relay loader chuck <NUM>; however, the present invention is not limited thereto and the relay loader chuck <NUM> may move in the -Z direction toward the main loader chuck <NUM>. The main loader chucks <NUM> may be configured to move back and forth in the +Z direction individually, or to move back and forth in the +Z direction as a whole (for example, together with the loader head). When the main loader chucks <NUM> move back and forth in the +Z direction as a whole, it is possible to simplify a driving system in the Z direction in the main loader chucks <NUM>.

The main loader chucks <NUM>, for example, are disposed to be aligned in the X direction at the predetermined interval d. Consequently, the relay loader <NUM> and the main loader <NUM> are allowed to face each other in the Z direction, two relay loader chucks <NUM> and two of the three main loader chucks <NUM> are brought into a state in which they face each other in a one-to-one manner.

The main loader <NUM> has a guide <NUM>. The guide <NUM> is disposed along the carrying-in part <NUM>, the first body <NUM>, the second body <NUM>, and the carrying-out part <NUM>. The main loader chuck <NUM> is movable along the guide <NUM> in the X direction (horizontal direction and direction orthogonal to the direction of the rotation axis AX1 of the spindle <NUM> or the like) together with the loader head (not illustrated) by driving a driving device (not illustrated). The main loader chuck <NUM> moves in the X direction, so that the main loader chuck <NUM> can be disposed for each of the carrying-in part <NUM>, the first body <NUM>, the second body <NUM>, and the carrying-out part <NUM>. Furthermore, when the main loader chuck <NUM> is disposed for the carrying-in part <NUM> or the like, a height of the guide <NUM> is set such that the main loader chuck <NUM> can receive and deliver the workpiece W at the height thereof. However, the main loader chuck <NUM> (or the loader head (not illustrated)) can also move vertically, and in such a case, the height of the guide <NUM> can be arbitrarily set.

The controller <NUM> collectively controls the operations of the first body <NUM>, the second body <NUM>, the carrying-in part <NUM>, the carrying-out part <NUM>, and the workpiece conveyance system <NUM> on the basis of a predetermined machining program. The controller <NUM> includes a communication part (not illustrated), and instructs the operations of the first body <NUM>, the second body <NUM>, the carrying-in part <NUM>, the carrying-out part <NUM>, and the workpiece conveyance system <NUM> and receives various types of information such as an operation status of each part by the communication part. Communication between the controller <NUM> and each part may be performed in a wired or wireless manner.

<FIG> is a diagram illustrating an example of the carrying-in part <NUM>. As illustrated in <FIG>, the carrying-in part <NUM> includes a holding table 31A and a conveyor belt <NUM>. The conveyor belt <NUM> can transport the workpiece W by placing the workpiece W on the upper surface thereof. The conveyor belt <NUM> is rotated in the X direction or the Z direction by a driver (not illustrated) in the state in which the workpiece W is placed thereon. The workpiece W, for example, is placed on the conveyor belt <NUM> at a position different from the carrying-in part <NUM>, and is disposed on the carrying-in part <NUM> by the rotation of the conveyor belt <NUM>. As described above, the workpiece W is placed on the conveyor belt <NUM>, so that the workpieces W can be continuously disposed on the carrying-in part <NUM> and the arrangement positions of the workpieces W on the carrying-in part <NUM> can be adjusted. The carrying-in part <NUM> is not limited to being provided with the conveyor belt <NUM> and may be configured to simply place the workpiece W on the holding table 31A.

As illustrated in <FIG>, the conveyor belt <NUM> places the workpiece W in a transverse direction, that is, in a state in which the center axis of the workpiece W is aligned along the Z direction. When the workpiece W is placed in the transverse direction, a positioning protrusion or the like may be provided on the conveyor belt <NUM>, for example, such that the workpiece W does not roll on the conveyor belt <NUM>. When the workpiece W is placed in the transverse direction, the main loader chuck <NUM> of the main loader <NUM> moves in the transverse direction from the - Z side of the workpiece W, and receives the workpiece W by grasping the workpiece W. Furthermore, the workpiece W is placed on the conveyor belt <NUM> with the -Z side of the workpiece W protruding so as not to interfere with the conveyor belt <NUM> or the holding table 31A when the main loader chuck <NUM> receives the workpiece W. As described above, the workpiece W is placed on the carrying-in part <NUM> in the transverse direction, so that it is possible to receive the workpiece W with the main loader chuck <NUM> of the main loader <NUM> directed to the transverse direction (toward the +Z direction) and it is not necessary to provide a structure that changes the orientation of the main loader chuck <NUM>.

<FIG> is a diagram illustrating another example of the main loader. As illustrated in <FIG>, the conveyor belt <NUM> may also place the workpiece W in a longitudinal direction, that is, in a state in which the center axis of the workpiece W is aligned along the Y direction. When an end surface of the workpiece W is a flat surface, the workpiece W can be placed on the conveyor belt <NUM> in the longitudinal direction. When the workpiece W is placed in the longitudinal direction, it is necessary to move the main loader chuck <NUM> of a main loader 52A toward the +Y direction (that is, the longitudinal direction) from the upper side to the lower side of the workpiece W. However, when the workpiece W is received and delivered from/to another part other than the carrying-in part <NUM>, since the main loader chuck <NUM> needs to direct the workpiece W toward the +Z direction (that is, the transverse direction), the main loader 52A needs to have a structure that changes the orientation of the main loader chuck <NUM>.

As illustrated in <FIG>, the main loader 52A includes a switching structure <NUM> that switches the orientation of the main loader chuck <NUM>. The switching structure <NUM> includes a driver (not illustrated), is provided between the loader head 52B and the main loader chuck <NUM>, and switches the orientation of the main loader chuck <NUM> between the +Z direction (transverse direction) and the -Y direction (longitudinal direction) by the driver. The switching structure <NUM> includes the driver (not illustrated) and switches the orientation of the main loader chuck <NUM> by the driver. Furthermore, the main loader 52A includes a lifting device (not illustrated) that moves the loader head 52B up and down, and moves the main loader chuck <NUM> up and down together with the loader head 52B.

The main loader 52A configured as above sets the main loader chuck <NUM> downward by the switching structure <NUM> above the workpiece W placed on the carrying-in part <NUM>, moves down the main loader chuck <NUM> by the lifting device (not illustrated), and holds the workpiece W by closing the grasping claws <NUM> at a stage where the grasping claws <NUM> are positioned outside the upper portion of the workpiece W. Thereafter, the main loader chuck <NUM> is switched in the transverse direction by the switching structure <NUM>, so that the workpiece W is held toward the +Z direction. As a consequence, it is possible to receive and deliver the workpiece W from/to the relay loader chuck <NUM> of the relay loader <NUM>.

<FIG> is a diagram illustrating another example of the carrying-in part <NUM>. When the switching structure <NUM> is not provided in the main loader 52A illustrated in <FIG>, since it is necessary to receive the workpiece W in the transverse direction, the workpiece W, which is placed on the carrying-in part <NUM> in the longitudinal direction, is changed in the transverse direction, so that it is possible to receive the workpiece W from the carrying-in part <NUM> by the main loader chuck <NUM>. The carrying-in part <NUM> illustrated in <FIG> can switch the workpiece W from the longitudinal direction to the transverse direction. As illustrated in <FIG>, the carrying-in part <NUM> has a holding table 31c and a holding structure <NUM> that holds the workpiece W. The holding structure <NUM> has a base portion 33a, a shaft portion 33b, and a holding portion 33c. The base portion 33a is attached to the holding table 31c; however, instead of this, for example, the base portion 33a may be attached to a conveyor, a rotary table, or the like for movement. The shaft portion 33b is disposed in parallel with the X direction on the upper portion of the base portion 33a.

The holding portion 33c is rotatable in the direction around the axis in the X direction centering on the shaft portion 33b with respect to the base portion 33a, and is rotated by the driver (not illustrated). The holding portion 33c includes grasping claws, a sucker, or the like and holds an end portion of the workpiece W. When the holding portion 33c moves in the direction around the axis of the shaft portion 33b, the orientation of the workpiece W can be switched between the transverse direction (Z direction) and the longitudinal direction (Y direction). Consequently, for example, in a state in which the workpiece W has been transported to the carrying-in part <NUM>, even though the workpiece W is directed in the longitudinal direction, when the workpiece W is delivered to the main loader <NUM>, it is possible to dispose the workpiece W from the longitudinal direction to the transverse direction by rotating the holding portion 33c. As a consequence, the main loader chuck <NUM> of the main loader <NUM> can receive the workpiece W in the transverse direction from the +Y side.

<FIG> is a diagram illustrating an example of the relay loader <NUM>, in which (A) illustrates a case where the relay loader <NUM> is viewed from the +Z direction (front side) and (B) illustrates a case where the relay loader <NUM> is viewed from the +Y direction (upper side). As illustrated in <FIG>, the relay loader <NUM> has relay loader chucks <NUM>, a shaft <NUM>, and a turning plate <NUM>. The relay loader chucks <NUM> are fixed to the turning plate <NUM>. The center axis AX2 of the shaft <NUM> is disposed in parallel with the Z direction. The turning plate <NUM> can be turned in the direction around the axis of the shaft <NUM> by the driver (not illustrated). In <FIG>, the relay loader <NUM> corresponding to the spindles <NUM> and <NUM> is described as an example; however, the same applies to the relay loader <NUM> corresponding to the spindles <NUM> and <NUM> except that it is configured to be symmetrical to the configuration illustrated in <FIG> and the turning orientation of the turning plate <NUM> is opposite.

When the turning plate <NUM> is turned in the direction around the axis of the shaft <NUM>, the relay loader <NUM> can move the relay loader chucks <NUM> between a first position P1 and a second position P2. When the turning plate <NUM> is at the first position P1, the relay loader chucks <NUM> face the spindle chucks <NUM> and <NUM> of the spindles <NUM> and <NUM>. Furthermore, when the turning plate <NUM> is at the second position P2, the relay loader chucks <NUM> face the main loader chucks <NUM> of the main loader <NUM>.

In the relay loader <NUM>, the turning position of the turning plate <NUM> is adjusted, so that it is possible to allow two relay loader chucks 53a and 53b and the spindles <NUM> and <NUM> to face each other at the first position P1. (A) in <FIG> illustrates a state in which the turning plate <NUM> indicated by one dot chain line allows the relay loader chuck 53a and the spindles <NUM> and <NUM> to face each other at the first position P1. Furthermore, as illustrated in (B) in <FIG>, the relay loader <NUM> is provided to be movable back and forth in the -Z direction by the driver (not illustrated). The relay loader chuck <NUM> is movable between a retracted position P1a retracted in the +Z direction in order to prevent the workpiece W from interfering with the spindles <NUM> and <NUM> during the turning of the turning plate <NUM> and an advancing position P1b advanced in the -Z direction in order to be able to receive and deliver the workpiece W from/to the spindles <NUM> and <NUM>. However, as described above, instead of the configuration in which the relay loader chuck <NUM> is movable back and forth in the -Z direction, it may be possible to employ a configuration in which the spindle chucks <NUM> and <NUM> are movable back and forth in the +Z direction.

Subsequently, the operation of the workpiece conveyance system <NUM> and the machine tool system <NUM> configured as described above will be described. <FIG> are diagrams illustrating an example of the operation of the machine tool system <NUM> including the workpiece conveyance system <NUM>. In the following example, a description will be given for an operation from a state in which workpieces W are machined by a cutting tool T (see (A) in <FIG>) in the spindles <NUM> and <NUM> of the first body <NUM> and the spindles <NUM> and <NUM> of the second body <NUM>, and machined workpieces W are held on the relay loader chucks 53b of the relay loader <NUM> corresponding to the respective spindles <NUM>, <NUM>, <NUM>, and <NUM>. In the drawings, in order to distinguish the machined workpieces W from the unmachined workpieces W, a plurality of dots are provided to the machined workpieces W.

As illustrated in <FIG>, the controller <NUM> instructs the main loader <NUM> to receive two workpieces W placed in advance on the carrying-in part <NUM>. The two workpieces W are disposed in advance on the carrying-in part <NUM> in the transverse direction and are set to have the interval d similar to the interval among three main loader chucks <NUM> or the interval between two relay loader chucks <NUM>. The controller <NUM> moves the three main loader chucks <NUM> of the main loader <NUM> in the +Z direction, and allows two main loader chucks 56a and 56b of the three main loader chucks <NUM> to simultaneously receive the two unmachined workpieces W. In such a case, a main loader chuck 56c moves in the +Z direction together with the other main loader chucks 56a and 56b, but is in an empty state of holding no workpiece W (state of holding no workpiece W, the same applies below).

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51a corresponding to the spindle <NUM> of the first body <NUM>. After or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51a holds the machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51a and the main loader chuck 56b holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51a and the main loader chuck 56c in the empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received and delivered from/to the relay loader chucks <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56c to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56c. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56b. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56b to the relay loader chuck 53a. As described above, the receiving and delivery of the unmachined workpiece W and the machined workpiece W between the relay loader 51a and the main loader <NUM> can be simultaneously performed in one operation.

With the aforementioned operation, in the relay loader 51a, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chuck 56c holds the machined workpiece W and the main loader chuck 56b at the center is in an empty state. The main loader chuck 56a maintains the state of holding the unmachined workpiece W as is. In the receiving and delivery operation of the workpieces W, since it is not necessary to change the orientation of the relay loader chuck <NUM> or the main loader chuck <NUM> for the receiving and delivery of the workpieces W, and the receiving and delivery of the workpieces W are performed in one operation, it is possible to shorten a time required for receiving and delivering the workpieces W. In the above, the main loader chucks <NUM> move in the +Z direction; however, instead of this configuration, the relay loader chuck <NUM> may be allowed to move in the -Z direction.

In addition, during the conveyance of the workpiece W by the main loader <NUM> and the receiving and delivery of the workpiece W from/to the next relay loader 51b, the controller <NUM> performs a series of controls to turn the turning plate <NUM> (see <FIG>) of the relay loader 51a having received the unmachined workpiece W to the first position P1, to allow the relay loader chuck 53b to receive a machined workpiece W from the spindle chuck <NUM> (see description of <FIG> to be described later), to turn the turning plate <NUM> by a predetermined amount, to allow the spindle chuck <NUM> to receive the unmachined workpiece W held by the relay loader chuck 53a (see description of <FIG> to be described later), to turn the turning plate <NUM> to the second position P2 in the state in which the relay loader chuck 53b holds the machined workpiece W (see description of <FIG> to be described later), and to allow the relay loader 51a to reach the state illustrated in <FIG>. In a manner similar to the receiving delivery of the workpieces W between the relay loader chuck <NUM> and the spindle chuck <NUM>, receiving and delivery of workpieces W between another relay loader chuck <NUM> and another main shaft chuck, <NUM>, or the like, can also be performed.

Next, as illustrated in <FIG>, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51b corresponding to the spindle <NUM> of the first body <NUM>. After or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51b holds a machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51b and the main loader chuck 56a holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51a and the main loader chuck 56b in the empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader 51b. Subsequently, the controller <NUM> closes the main loader chuck 56b to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56b. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56a. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56a to the relay loader chuck 53a. As described above, the receiving and delivery of the unmachined workpiece W and the machined workpiece W between the relay loader 51b and the main loader <NUM> can be simultaneously performed in one operation.

With the aforementioned operation, in the relay loader 51b, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chuck 56b holds the machined workpiece W and the main loader chuck 56a is in an empty state. The main loader chuck 56c maintains the state of holding the machined workpiece W as is. Similar to the above description, the receiving and delivery operation of the workpieces W can shorten a time required for receiving delivering the workpieces W.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader <NUM> along the guide <NUM> in the +X direction, and allows the main loader chucks <NUM> to face the carrying-out chucks <NUM> of the carrying-out part <NUM>. In such a case, the controller <NUM> allows the two main loader chucks 56b and 56c holding the machined workpieces W and two carrying-out chucks <NUM> to face each other. An interval between the two carrying-out chucks <NUM> is set to the interval d, similar to the interval among the main loader chucks <NUM>. Subsequently, as illustrated in <FIG>, the controller <NUM> moves the main loader chucks <NUM> in the +Z direction to a position where the workpieces W can be received and delivered from/to the carrying-out chucks <NUM>.

Subsequently, the controller <NUM> allows each carrying-out chuck <NUM> to hold the machined workpiece W and releases the main loader chucks 56b and 56c. As a consequence, the two machined workpieces W are simultaneously or almost simultaneously delivered from the main loader chucks 56b and 56c to the carrying-out chucks <NUM>, respectively. As described above, between the main loader <NUM> and the carrying-out part <NUM>, a plurality of (two) workpieces W can be simultaneously received and delivered in one operation. With such an operation, in the main loader <NUM>, the three main loader chucks <NUM> are in an empty state, move along the guide <NUM> in the -X direction, and return to the carrying-in part <NUM>, so that two unmachined workpieces W can be held by the main loader chucks <NUM> as illustrated in <FIG>.

As described above, while the main loader <NUM> moves once in the +X direction from the carrying-in part <NUM> to the carrying-out part <NUM>, the main loader <NUM> continuously receives and delivers workpieces W from/to the two relay loaders 51a and 51b disposed in the first body <NUM>. That is, by one-time movement in the +X direction, the main loader <NUM> conveys two unmachined workpieces W on the carrying-in part <NUM> to the relay loaders 51a and 51b, respectively, receives machined workpieces W from the relay loaders 51a and 51b, and conveys the machined workpieces W to the carrying-out part <NUM>.

Next, in a manner similar to the illustration in <FIG>, the main loader chucks <NUM> hold two unmachined workpieces W on the carrying-in part <NUM>, move along the guide <NUM> in the +X direction, deliver the unmachined workpiece W to the relay loader chucks <NUM> of the relay loader 51a corresponding to the spindle <NUM> of the second body <NUM>, and receive machined workpieces W. The receiving and delivery operation of the workpieces W is similar to the operation illustrated in <FIG>. Next, in a manner similar to the illustration in <FIG>, the main loader chucks <NUM> move along the guide <NUM> in the +X direction, deliver unmachined workpieces W to the relay loader chucks <NUM> of the relay loader 51b corresponding to the spindle <NUM> of the second body <NUM>, and receive machined workpieces W. The receiving and delivery operation of the workpieces W is similar to the operation illustrated in <FIG>. Next, the main loader chucks <NUM> move along the guide <NUM> in the +X direction and deliver the machined workpieces W to the carrying-out chucks <NUM> of the carrying-out part <NUM>.

In the main loader <NUM>, the main loader chucks <NUM> are in an empty state and return to the carrying-in part <NUM>, so that the main loader chucks <NUM> can hold two unmachined workpieces W as illustrated in <FIG>. Such an operation is repeated, so that unmachined workpieces W are continuously supplied to the spindles <NUM> and <NUM> of the first body <NUM> and the spindles <NUM> and <NUM> of the second body <NUM> and machined workpieces W are continuously collected. The machined workpieces W held by the carrying-out chucks <NUM> of the carrying-out part <NUM>, for example, are transported from the carrying-out part <NUM> to another place by a conveyor device or the like. In the present embodiment, the receiving and delivery operation of the workpieces W by the main loader chucks <NUM> is repeated twice (n = <NUM>) for the spindles <NUM> and <NUM> or the spindles <NUM> and <NUM>, respectively.

As described above, according to the present embodiment, since a plurality of the workpieces W can be simultaneously delivered and received, and the main loader <NUM> does not frequently reciprocate between the relay loaders <NUM> and the carrying-in part <NUM> or between the relay loaders <NUM> and the carrying-out part <NUM>, a time required for receiving and delivering the workpieces W is shortened to improve the efficiency in conveying the workpieces W, and thus the efficiency in machining the workpieces W can be improved. In the aforementioned embodiment, an example corresponding to the first body <NUM> and the second body <NUM> each having two spindles has been described; however, even though each body has three or more spindles, (the number of spindles + m) main loader chucks <NUM> are disposed, so that it is possible to cope with the situation in a manner similar to the above description. Furthermore, it would be similar to the above even though there are one or three or more bodies each having two spindles. Furthermore, the number of main loader chucks <NUM> is <NUM> (which is equal to the number of spindles (two) plus one); however, the present invention is not limited to this configuration and, for example, four or more main loader chucks <NUM> may be provided for two spindles because it is sufficient if the number of main loader chucks <NUM> is the number of spindles plus m.

A second embodiment will be described with reference to the drawings. <FIG> is a diagram illustrating an example of a workpiece conveyance system <NUM> and a machine tool system <NUM> according to the second embodiment. As illustrated in <FIG>, the machine tool system <NUM> includes the first body (machine tool body) <NUM>, the second body (machine tool body) <NUM>, the carrying-in part <NUM>, the carrying-out part <NUM>, the workpiece conveyance system <NUM>, and the controller <NUM>. In the second embodiment, the configuration of the workpiece conveyance system <NUM> is different from that of the first embodiment and the other configurations are similar to those of the first embodiment. In the following description, the same or equivalent components as those of the first embodiment are denoted by the same reference numerals and a description thereof will be omitted or simplified.

The workpiece conveyance system <NUM> has relay loaders <NUM> and a main loader <NUM>. The relay loader <NUM> has a configuration similar to that of the first embodiment. Like in the first embodiment, the number of spindles <NUM> and <NUM> of the first body <NUM> is set to n (which is an integer satisfying n ≥ <NUM>). In the present embodiment, four relay loaders <NUM> disposed in the first body <NUM> and the second body <NUM> are distinguished from one another, and a relay loader 51a is disposed corresponding to the spindle <NUM> of the first body <NUM>, a relay loader 51b is disposed corresponding to the spindle <NUM> of the first body <NUM>, a relay loader 51c is disposed corresponding to the spindle <NUM> of the second body <NUM>, and a relay loader 51d is disposed corresponding to the spindle <NUM> of the second body <NUM>.

Furthermore, in the present embodiment, the main loader <NUM> has five main loader chucks <NUM> of n + m (m = <NUM>). The five main loader chucks <NUM> are juxtaposed at the interval d in the X direction. Each of the main loader chucks <NUM> has a configuration similar to that of the first embodiment described above. Hereinafter, when the five main loader chucks <NUM> are distinguished from one another, they are sequentially denoted as main loader chucks 56a, 56b, 56c, 56d, and 56e from the -X side to the +X side.

On the carrying-in part <NUM>, four unmachined workpieces W are placed in parallel to correspond to the main loader chucks 56a to 56d. The fact that the four workpieces W are disposed at the interval d is similar to that of the first embodiment. Furthermore, the carrying-out part <NUM> has four carrying-out chucks <NUM> so as to correspond to the main loader chucks 56b to 56e. The fact that the carrying-out chucks <NUM> are juxtaposed at the interval d is similar to that of the first embodiment.

Subsequently, the operation of the workpiece conveyance system <NUM> and the machine tool system <NUM> configured as described above will be described. <FIG> are diagrams illustrating an example of the operation of the machine tool system <NUM> including the workpiece conveyance system <NUM>. In the following example, as in the first embodiment, a description will be given for an operation from a state in which workpieces W are machined by the cutting tool T (see (A) in <FIG>) in the spindle <NUM> and <NUM> of the first body <NUM> and the spindle <NUM> and <NUM> of the second body <NUM>, and machined workpieces W are held on the relay loader chucks 53b of the relay loaders 51a to 51d corresponding to respective the spindles <NUM>, <NUM>, <NUM>, and <NUM>.

As illustrated in <FIG>, the controller <NUM> allows the main loader chucks <NUM> of the main loader <NUM> to receive the four unmachined workpieces W placed on the carrying-in part <NUM>. The receiving procedure of the workpieces W by each of the main loader chucks <NUM> is similar to that of the first embodiment. The controller <NUM> allows the four main loader chucks 56a, 56b, 56c, and 56d of the five main loader chucks <NUM> of the main loader <NUM> to simultaneously receive the unmachined workpieces W. Consequently, the main loader chuck 56e is in an empty state.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51a corresponding to the spindle <NUM> of the first body <NUM>. As in the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51a holds the machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51a and the main loader chuck 56d holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51a and the main loader chuck 56e in the empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the five main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received and delivered from/to the relay loader chucks <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56e to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56e. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56d. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56d to the relay loader chuck 53a.

With the aforementioned operation, in the relay loader 51a, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chuck 56e holds the machined workpiece W, the main loader chuck 56d is in an empty state, and the main loader chucks 56a to 56c maintain the state of holding the unmachined workpiece W as is.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51b corresponding to the spindle <NUM> of the first body <NUM>. In a manner similar to the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51b holds the machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51b and the main loader chuck 56c holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51b and the main loader chuck 56d in an empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the five main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chucks <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56d to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56d. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56c. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56c to the relay loader chuck 53a.

With the aforementioned operation, in the relay loader 51b, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chucks 56d and 56e hold the machined workpieces W, the main loader chuck 56c is in an empty state, and the main loader chucks 56a and 56b maintain the state of holding the unmachined workpieces W as is. Although not illustrated in the second embodiment, the receiving and delivery of the workpieces W between the relay loader chuck <NUM> and the spindle chuck <NUM> is similar to the operation of the aforementioned relay loaders 51a illustrated in <FIG> and <FIG>.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51c corresponding to the spindle <NUM> of the second body <NUM>. In a manner similar to the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51c holds the machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51c and the main loader chuck 56b holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51c and the main loader chuck 56c in the empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the five main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chucks <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56c to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56c. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56b. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56b to the relay loader chuck 53a.

With the aforementioned operation, in the relay loader 51c, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chucks 56c to 56e hold the machined workpieces W, the main loader chuck 56b is in an empty state, and the main loader chuck 56a maintains the state of holding the unmachined workpiece W as is.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chucks <NUM> of the relay loader 51d corresponding to the spindle <NUM> of the second body <NUM>. In a manner similar to the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck 53b of the relay loader 51d holds the machined workpiece W received from the spindle <NUM> and the relay loader chuck 53a is empty, the controller <NUM> disposes the relay loader chucks <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck 53a in the empty state in the relay loader 51d and the main loader chuck 56a holding the unmachined workpiece W in the main loader <NUM> to face each other. In such a state, the relay loader chuck 53b holding the machined workpiece W in the relay loader 51d and the main loader chuck 56b in the empty state in the main loader <NUM> are in a state of simultaneously facing each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the five main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chucks <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56b to hold the machined workpiece W and then releases the relay loader chuck 53b. As a consequence, the machined workpiece W is delivered from the relay loader chuck 53b to the main loader chuck 56b. Simultaneously or almost simultaneously, the controller <NUM> closes the relay loader chuck 53a to hold the unmachined workpiece W and then releases the main loader chuck 56a. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56a to the relay loader chuck 53a.

With the aforementioned operation, in the relay loader 51d, the relay loader chuck 53a holds the unmachined workpiece W and the relay loader chuck 53b is in an empty state. Furthermore, in the main loader <NUM>, the main loader chucks 56b to 56e hold the machined workpieces W and the main loader chuck 56a is in an empty state.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the carrying-out chucks <NUM> of the carrying-out part <NUM>. Next, as illustrated in <FIG>, the controller <NUM> moves the five main loader chucks <NUM> in the +Z direction to a position where the workpieces W can be received from and delivered to the carrying-out chucks <NUM>. Subsequently, the controller <NUM> allows each carrying-out chuck <NUM> to hold the machined workpiece W and then releases the main loader chucks 56b to 56e. As a consequence, the four machined workpieces W are simultaneously or almost simultaneously delivered from the main loader chucks 56b to 56e to the carrying-out chucks <NUM>, respectively. With such an operation, in the main loader <NUM>, the five main loader chucks <NUM> are in an empty state, move along the guide <NUM> in the -X direction, and return to the carrying-in part <NUM>, so that four unmachined workpieces W can be held by the main loader chucks <NUM> as illustrated in <FIG>.

As described above, while the main loader <NUM> moves once in the +X direction from the carrying-in part <NUM> to the carrying-out part <NUM>, the main loader <NUM> continuously receives and delivers workpieces W from/to the four relay loaders 51a to 51d disposed in the first body <NUM> and the second body <NUM>. That is, by one-time movement in the +X direction, the main loader <NUM> conveys four unmachined workpieces W on the carrying-in part <NUM> to the relay loaders 51a to 51d, respectively, receives machined workpieces W from the relay loaders 51a to 51d, and conveys the machined workpieces W to the carrying-out part <NUM>. In the present embodiment, the receiving and delivery operation of the workpieces W by the main loader chucks <NUM> is repeated four times (n = <NUM>) for the spindles <NUM>, <NUM>, <NUM>, and <NUM>.

As described above, according to the present embodiment, since unmachined workpieces W are supplied to the spindles <NUM>, <NUM>, <NUM>, and <NUM>, and machined workpieces W are collected, while the main loader <NUM> reaches the carrying-out part <NUM> from the carrying-in part <NUM>, a time required for receiving and delivering the workpieces W is shortened, and the efficiency in conveying the workpieces W can be improved. In the aforementioned embodiment, five (= <NUM> + four spindles <NUM>, <NUM>, <NUM>, and <NUM>) main loader chucks <NUM> are used; however, the present invention is not limited to this configuration and, for example, six or more main loader chucks <NUM> may be provided for four spindles because it is sufficient if the number of main loader chucks <NUM> is the number of spindles + m.

A third embodiment will be described with reference to the drawings. <FIG> is a diagram illustrating an example of a workpiece conveyance system <NUM> and a machine tool system <NUM> according to the third embodiment. As illustrated in <FIG>, the machine tool system <NUM> includes the first body (machine tool body) <NUM>, the second body (machine tool body) <NUM>, the carrying-in part <NUM>, the carrying-out part <NUM>, the workpiece conveyance system <NUM>, and the controller <NUM>. In the third embodiment, the configuration of the workpiece conveyance system <NUM> is different from that of the first embodiment and the other configurations are similar to those of the first embodiment. In the following description, the same or equivalent components as those of the first embodiment are denoted by the same reference numerals and a description thereof will be omitted or simplified.

The workpiece conveyance system <NUM> includes a main loader <NUM> but includes no relay loader. In the third embodiment, as in the first embodiment, a description will be given in which n, which is the number of spindles <NUM> and <NUM> of the first body <NUM>, is set to <NUM>. The main loader <NUM> is movable along a guide <NUM> in the X direction. The guide <NUM> is different from the guide <NUM> of the first embodiment, and is disposed along the X direction on the +Z side of the first body <NUM> and the second body <NUM>.

The main loader chucks <NUM> have a configuration similar to that illustrated in the first embodiment, except that the main loader chucks <NUM> are disposed to face the spindle chuck <NUM> or the like. Similar to the guide <NUM> of the first embodiment, the guide <NUM> may be disposed on the -Z side of the first body <NUM> and the second body <NUM>. In such a case, the main loader <NUM> is provided with a structure that allows the main loader chucks <NUM> to face the spindle chuck <NUM> or the like. Furthermore, the carrying-in part <NUM> is similar to the first embodiment, except that the carrying-in part <NUM> holds unmachined workpieces W in the +Z direction.

Subsequently, the operation of the workpiece conveyance system <NUM> and the machine tool system <NUM> configured as described above will be described. <FIG> are diagrams illustrating an example of the operation of the machine tool system <NUM> including the workpiece conveyance system <NUM>. In the following example, as in the first embodiment, a description will be given for an operation from a state in which workpieces W are machined by the cutting tool T (see (A) in <FIG>) in the spindles <NUM> and <NUM> of the first body <NUM> and the spindles <NUM> and <NUM> of the second body <NUM>, and machined workpieces W are held on the spindles <NUM>, <NUM>, <NUM>, and <NUM>, respectively.

As illustrated in <FIG>, the controller <NUM> moves the main loader chucks <NUM> in the -Z direction and allows the main loader chucks <NUM> of the main loader <NUM> to receive two unmachined workpiece W placed on the carrying-in part <NUM>. The receiving procedure of the workpieces W by each of the main loader chucks <NUM> is similar to that of the first embodiment. The controller <NUM> allows the two main loader chucks 56a and 56b of the three main loader chucks <NUM> of the main loader <NUM> to simultaneously receive the unmachined workpieces W. Consequently, the main loader chuck 56c is in an empty state.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the +Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chuck 56c of the main loader chucks <NUM> at a position where the main loader chuck 56c can face the spindle chuck <NUM> of the spindle <NUM>. Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the -Z direction to a position where the workpiece W can be received from and delivered to the spindle chuck <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56c to hold the machined workpiece W and then releases the spindle chuck <NUM>. As a consequence, the machined workpiece W is delivered from the spindle chuck <NUM> to the main loader chuck 56c.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the +Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and then disposes the main loader chuck 56b holding the unmachined workpiece W among the main loader chucks <NUM> at a position where the main loader chuck 56b can face the spindle chuck <NUM> of the spindle <NUM>. Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the -Z direction to a position where the workpiece W can be received from and delivered to the spindle chuck <NUM>. Subsequently, the controller <NUM> closes the main shaft chuck <NUM> to hold the unmachined workpiece W and then releases the main loader chuck 56b. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56b to the spindle chuck <NUM>.

With the aforementioned operation, in the main loader <NUM>, the main loader chuck 56c holds the machined workpiece W, the main loader chuck 56b is in an empty state, and the main loader chuck 56a maintains the state of holding the unmachined workpiece W as is.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the +Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chuck 56b of the main loader chucks <NUM> at a position where the main loader chuck 56b can face the main spindle <NUM> of the spindle <NUM>. Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the -Z direction to a position where the workpiece W can be received from and delivered to the spindle chuck <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56b to hold the machined workpiece W and then releases the spindle chuck <NUM>. As a consequence, the machined workpiece W is delivered from the main shaft chuck <NUM> to the main loader chuck 56b.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the +Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chuck 56a holding the unmachined workpiece W among the main loader chucks <NUM> at a position where the main loader chuck 56a can face the spindle chuck <NUM> of the spindle <NUM>. Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the -Z direction to a position where the workpiece W can be received from and delivered to the spindle chuck <NUM>. Subsequently, the controller <NUM> closes the spindle chuck <NUM> to hold the unmachined workpiece W and then releases the main loader chuck 56a. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56a to the spindle chuck <NUM>.

With the aforementioned operation, in the main loader <NUM>, the main loader chucks 56b and 56c hold the machined workpiece W and the main loader chuck 56a is in an empty state. Next, the controller <NUM> moves back the main loader chucks <NUM> in the +Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the carrying-out chucks <NUM> of the carrying-out part <NUM>.

Next, as illustrated in <FIG>, the controller <NUM> moves back the three main loader chucks <NUM> in the -Z direction to a position where the workpieces W can be received from and delivered to the carrying-out chucks <NUM>. Subsequently, the controller <NUM> allows each carrying-out chuck <NUM> to hold the machined workpiece W and then releases the main loader chucks 56b and 56c. As a consequence, the two machined workpieces W are simultaneously or almost simultaneously delivered from the main loader chucks 56b and 56c to the carrying-out chucks <NUM>, respectively. With such an operation, in the main loader <NUM>, the three main loader chucks <NUM> are in an empty state, move along the guide <NUM> in the -X direction, and return to the carrying-in part <NUM>, so that two unmachined workpieces W can be held by the main loader chucks <NUM> as illustrated in <FIG>.

As described above, while the main loader <NUM> moves once in the +X direction from the carrying-in part <NUM> to the carrying-out part <NUM>, the main loader <NUM> continuously receives and delivers workpieces W from/to the two spindle chucks <NUM> and <NUM> disposed in the first body <NUM>. That is, by one-time movement in the +X direction, the main loader <NUM> conveys two unmachined workpieces W on the carrying-in part <NUM> to the spindle chucks <NUM> and <NUM>, respectively, receives machined workpieces W from the spindle chucks <NUM> and <NUM>, and conveys the machined workpieces W to the carrying-out part <NUM>.

Next, in a manner similar to the illustration in <FIG>, the main loader chucks <NUM> hold two unmachined workpieces W on the carrying-in part <NUM>, move along the guide <NUM> in the +X direction, receive a machined workpiece W from the spindle chuck <NUM> of the spindle <NUM> of the second body <NUM>, and deliver the unmachined workpiece W. The receiving and delivery operation of the workpieces W is similar to the operations in <FIG> and <FIG>. Next, the main loader chucks <NUM> move along the guide <NUM> in the +X direction, receive a machined workpiece W from the spindle chuck <NUM> of the spindle <NUM> of the second body <NUM>, and deliver the unmachined workpiece W. The receiving and delivery operation of the workpieces W is similar to the operations in <FIG> and <FIG>. Next, the main loader chucks <NUM> move along the guide <NUM> in the +X direction and deliver the machined workpieces W to the carrying-out chucks <NUM> of the carrying-out part <NUM>.

In the main loader <NUM>, the main loader chucks <NUM> are in an empty state and return to the carrying-in part <NUM>, so that the main loader chucks <NUM> can hold two unmachined workpieces W as illustrated in <FIG>. Such an operation is repeated, so that unmachined workpieces W are continuously supplied to the spindles <NUM> and <NUM> of the first body <NUM> and the spindles <NUM> and <NUM> of the second body <NUM> and machined workpieces W are continuously collected. In the present embodiment, the receiving and delivery operation of the workpieces W by the main loader chucks <NUM> is repeated twice (n = <NUM>) for the spindles <NUM> and <NUM> or the spindles <NUM> and <NUM>, respectively.

As described above, according to the present embodiment, since unmachined workpieces W are supplied to the spindles <NUM> and <NUM> or the spindles <NUM> and <NUM>, and machined workpieces W are collected, while the main loader <NUM> reaches the carrying-out part <NUM> from the carrying-in part <NUM>, a time required for receiving and delivering the workpieces W is shortened, and the efficiency in conveying the workpieces W can be improved. Furthermore, according to the present embodiment, it is possible to reduce the equipment cost because no relay loader is used. In the aforementioned embodiment, three (which is equal to the number of spindles <NUM> and <NUM> (n = <NUM>) plus one) main loader chucks <NUM> are used; however, four or more main loader chucks <NUM> may be used. Furthermore, as in the second embodiment, five (= <NUM> + four spindles <NUM>, <NUM>, <NUM>, and <NUM>) main loader chucks <NUM> may also be used. In such a case, the receiving and delivery operation of the workpieces W by the main loader chucks <NUM> is repeated four times (n = <NUM>) for the spindle <NUM> or the like.

A fourth embodiment will be described with reference to the drawings. <FIG> is a diagram illustrating an example of a workpiece conveyance system <NUM> and a machine tool system <NUM> according to the fourth embodiment. As illustrated in <FIG>, the machine tool system <NUM> includes the first body (machine tool body) <NUM>, the second body (machine tool body) <NUM>, the carrying-in part <NUM>, the carrying-out part <NUM>, the workpiece conveyance system <NUM>, and the controller <NUM>. In the fourth embodiment, the configuration of the workpiece conveyance system <NUM> is different from that of the first embodiment and the other configurations are similar to those of the first embodiment. In the following description, the same or equivalent components as those of the first embodiment are denoted by the same reference numerals and a description thereof will be omitted or simplified.

The workpiece conveyance system <NUM> has relay loaders <NUM> and a main loader <NUM>. In the relay loader <NUM>, one relay loader chuck <NUM> is provided to the turning plate <NUM> (see <FIG>). That is, the spindle shaft chuck <NUM> or the like of the spindle <NUM> or the like and the relay loader chucks <NUM> of each relay loader <NUM> correspond to each other in a one-to-one manner. Similar to the relay loader <NUM> of the first embodiment, the relay loader <NUM> can move the relay loader chuck <NUM> to the first position P1, where the relay loader chuck <NUM> faces the spindle chuck <NUM> or the like, and the second position P2, where the relay loader chuck <NUM> faces the main loader chuck <NUM> of the main loader <NUM>, by turning the turning plate <NUM>. The main loader <NUM> has a configuration similar to that of the first embodiment.

As illustrated in <FIG>, the controller <NUM> allows the main loader chucks <NUM> of the main loader <NUM> to receive two unmachined workpieces W placed on the carrying-in part <NUM>. The receiving procedure of the workpieces W by each of the main loader chucks <NUM> is similar to that of the first embodiment. The controller <NUM> allows the two main loader chucks 56a and 56b of the three main loader chucks <NUM> of the main loader <NUM> to simultaneously receive the unmachined workpieces W. Consequently, the main loader chuck 56c is in an empty state.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chuck <NUM> of a relay loader 451a corresponding to the spindle <NUM> of the first body <NUM>. As in the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck <NUM> of the relay loader 451a holds the machined workpiece W received from the spindle <NUM>, the controller <NUM> disposes the relay loader chuck <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck <NUM> of the relay loader 451a and the main loader chuck 56c in the empty state in the main loader <NUM> to face each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chuck <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56c to hold the machined workpiece W and then releases the relay loader chuck <NUM>. As a consequence, the machined workpiece W is delivered from the relay loader chuck <NUM> to the main loader chuck 56c. Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and allows the relay loader chuck <NUM> of a relay loader 451a and the main loader chuck 56b holding the unmachined workpiece W in the main loader <NUM> to face each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chuck <NUM>. Subsequently, the controller <NUM> closes the relay loader chuck <NUM> to hold the unmachined workpiece W and then releases the main loader chuck 56b. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56b to the relay loader chuck <NUM>. With the aforementioned operation, in the main loader <NUM>, the main loader chuck 56c holds the machined workpiece W, the main loader chuck 56b is in an empty state, and the main loader chuck 56a maintains the state of holding the unmachined workpiece W as is.

In addition, during the conveyance of the workpiece W by the main loader <NUM> and the receiving and delivery of the workpiece W from/to a next relay loader 451b, the controller <NUM> performs a series of controls to turn the turning plate <NUM> (see <FIG>) of the relay loader 451a having received the unmachined workpiece W to the first position P1, to allow the spindle chuck <NUM> to receive an unmachined workpiece W held by the relay loader chuck <NUM> (see description of <FIG> to be described later), and to turn the turning plate <NUM> to the second position P2. In a manner similar to the receiving and delivery of the workpieces W between the relay loader chuck <NUM> and the spindle chuck <NUM>, receiving and delivery of workpieces W between another relay loader chuck <NUM> and another main shaft chuck <NUM>, or the like, can also be performed.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the relay loader chuck <NUM> of the relay loader 451b corresponding to the spindle <NUM> of the first body <NUM>. In a manner similar to the first embodiment, after or before the main loader chucks <NUM> are reached, in a state in which the relay loader chuck <NUM> of the relay loader 451b holds the machined workpiece W received from the spindle <NUM>, the controller <NUM> disposes the relay loader chuck <NUM> at the second position P2. The controller <NUM> allows the relay loader chuck <NUM> holding the machined workpiece W in the relay loader 451b and the main loader chuck 56b in the empty state in the main loader <NUM> to face each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chuck <NUM>. Subsequently, the controller <NUM> closes the main loader chuck 56b to hold the machined workpiece W and then releases the relay loader chuck <NUM>. As a consequence, the machined workpiece W is delivered from the relay loader chuck <NUM> to the main loader chuck 56b. Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and allows the relay loader chuck <NUM> of a relay loader 451b and the main loader chuck 56a holding the unmachined workpiece W in the main loader <NUM> to face each other.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpiece W can be received from and delivered to the relay loader chuck <NUM>. Subsequently, the controller <NUM> closes the relay loader chuck <NUM> to hold the unmachined workpiece W and then releases the main loader chuck 56a. As a consequence, the unmachined workpiece W is delivered from the main loader chuck 56a to the relay loader chuck <NUM>. With the aforementioned operation, in the main loader <NUM>, the main loader chucks 56b and 56c hold the machined workpieces W and the main loader chuck 56a is in an empty state.

Next, the controller <NUM> moves back the main loader chucks <NUM> in the -Z direction, then moves the main loader chucks <NUM> along the guide <NUM> in the +X direction, and disposes the main loader chucks <NUM> at a position where the main loader chucks <NUM> can face the carrying-out chucks <NUM> of the carrying-out part <NUM>.

Next, as illustrated in <FIG>, the controller <NUM> moves the three main loader chucks <NUM> in the +Z direction to a position where the workpieces W can be received from and delivered to the carrying-out chucks <NUM>. Subsequently, the controller <NUM> allows each carrying-out chuck <NUM> to hold the machined workpiece W and then releases the main loader chucks 56b and 56c. As a consequence, the two machined workpieces W are simultaneously or almost simultaneously delivered from the main loader chucks 56b and 56c to the carrying-out chucks <NUM>, respectively. With such an operation, in the main loader <NUM>, the three main loader chucks <NUM> are in an empty state, move along the guide <NUM> in the -X direction, and return to the carrying-in part <NUM>, so that two unmachined workpieces W can be held by the main loader chucks <NUM> as illustrated in <FIG>.

As described above, even though there is one relay loader chuck <NUM> in each relay loader 451a or the like, while the main loader <NUM> moves once in the +X direction from the carrying-in part <NUM> to the carrying-out part <NUM>, the main loader <NUM> continuously receives and delivers workpieces W from/to the two spindle chucks <NUM> and <NUM> disposed in the first body <NUM>.

Next, in a manner similar to the illustration in <FIG>, the main loader chucks <NUM> hold two unmachined workpieces W on the carrying-in part <NUM>, move along the guide <NUM> in the +X direction, receive a machined workpiece W from the relay loader chuck <NUM> of the relay loader 451a of the second body <NUM>, and deliver the unmachined workpiece W. The receiving and delivery operation of the workpieces W is similar to the operations in <FIG> and <FIG>. Next, the main loader chucks <NUM> move along the guide <NUM> in the +X direction, receive a machined workpiece W from the relay loader chuck <NUM> of the relay loader 451b of the second body <NUM>, and deliver the unmachined workpiece W. The receiving and delivery operation of the workpieces W is similar to operations in <FIG> and <FIG>. Next, the main loader chucks <NUM> move along the guide <NUM> in the +X direction and deliver the machined workpieces W to the carrying-out chucks <NUM> of the carrying-out part <NUM>.

As described above, according to the present embodiment, since unmachined workpieces W are supplied to the spindles <NUM> and <NUM> or the spindles <NUM> and <NUM>, and machined workpieces W are collected, while the main loader <NUM> reaches the carrying-out part <NUM> from the carrying-in part <NUM>, a time required for receiving and delivering the workpieces W is shortened, and the efficiency in conveying the workpieces W can be improved. Furthermore, according to the present embodiment, since there is only one relay loader chuck <NUM> in each relay loader 451a or the like, it is possible to reduce the equipment cost by simplifying the configurations of the relay loader 451a or the like. In the aforementioned embodiment, three (which is equal to the number of spindles <NUM> and <NUM> (n = <NUM>) plus one) main loader chucks <NUM> are used; however, four or more main loader chucks <NUM> may be used. Furthermore, as in the second embodiment, five (= <NUM> + four spindles <NUM>, <NUM>, <NUM>, and <NUM>) main loader chucks <NUM> may also be used. In such a case, the receiving and delivery operation of the workpieces W by the main loader chucks <NUM> is repeated four times (n = <NUM>) for the spindle <NUM> or the like.

So far, although the embodiments have been described, the present invention is not limited to the aforementioned description and various modifications can be made without departing from the scope of the present claims. For example, the workpiece conveyance system may be configured by replacing a part of the relay loader <NUM> of the first embodiment with the relay loader <NUM> of the fourth embodiment. Furthermore, in the first and second embodiments, the configuration in which the relay loader chucks <NUM> and the main loader chucks <NUM> are disposed at the same interval d has been described as an example; however, the present invention is not limited to this configuration and the interval between the relay loader chucks <NUM> and the interval between the main loader chucks <NUM> may be different from each other.

Furthermore, in the aforementioned first, second, and fourth embodiments, switching between the first position P1 and the second position P2 is performed by turning the turning plate <NUM> as the relay loaders <NUM> and <NUM>; however, the present invention is not limited to this configuration. For example, the relay loader chuck <NUM> may also be configured to be slidable in an up and down direction (Y direction) or the like as the relay loaders <NUM> and <NUM>.

Claim 1:
A machine tool system (<NUM>; <NUM>; <NUM>; <NUM>) comprising at least one body (<NUM>, <NUM>), each body (<NUM>, <NUM>) with n workpiece holders (<NUM>, <NUM>, <NUM>, <NUM>) (where n is an integer satisfying n ≥ <NUM>), and a workpiece conveyance system (<NUM>; <NUM>; <NUM>; <NUM>) which comprises
a main loader (<NUM>; <NUM>; <NUM>) with n + m main loader chucks (<NUM>, 56a..e), where m is an integer satisfying m ≥ <NUM>, and n relay loaders (<NUM>, 51a...d; <NUM>)
wherein the main loader chucks (<NUM>, 56a...e) are adapted to receive and deliver workpieces to be machined (W) from/to the n workpiece holders (<NUM>, <NUM>, <NUM>, <NUM>) and from/to the n relay loaders (<NUM>, 51a...d; <NUM>), which are disposed corresponding to the n respective workpiece holders (<NUM>, <NUM>, <NUM>, <NUM>) to receive and deliver the workpieces (W) from/to the workpiece holders (<NUM>, <NUM>, <NUM>, <NUM>).