JPH04354640A - Tool storage device for lathe cell - Google Patents

Abstract

PURPOSE:To improve the indexing precision of a chain type tool storage device provided on a lathe cell. CONSTITUTION:A tool storage device 60 provided on a lathe cell is arranged on both side sections of a base 500. A tool magazine and a jaw magazine are formed on two endless chains suspended in parallel between a driving sprocket 610 and a driven sprocket 620. A driven sprocket 615 for position detection is provided at the intermediate section between both sprockets 610, 620, the shift quantity of chains is detected by a rotary encoder, and the driving sprocket 610 is controlled by a servo-motor 612 for indexing. A service position for the tool/jaw exchange is set immediately above the sprocket 615.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lathe and a lathe cell equipped with a conveyance device for storing and automatically feeding jigs and workpieces used by the lathe.

0002

2. Description of the Related Art A lathe cell is known which includes a multi-tasking lathe, a storage device for jigs and workpieces used by the multi-tasking lathe, and a device for transporting the jigs and tools and workpieces. In the lathe cell, by preparing a large amount of spare jigs and tools used by the multi-tasking lathe, it is possible to unmannedly produce a wide variety of workpieces over a long period of time. Examples of the types of jigs include chuck jaws that are attached to the spindle chuck of a lathe, and examples of tools include cutting tools that are supplied to the tool rest of the lathe. As the transport device, for example, a gantry robot that runs on a guide rail is used. The hand attached to the end of the robot's arm is used to hold jigs, tools,
Since you will be handling workpieces, etc., prepare hands appropriate for the purpose and replace them as appropriate.

0003

A lathe cell requires space because it is constructed by disposing a storage device for setup members such as jigs and tools and a storage device for workpieces around the lathe. In particular, the storage device for setup members stores spare jigs and tools, so if a large amount of jigs and tools are to be stored, the device will become larger and the space will increase. As the equipment becomes larger,
This results in disadvantages such as the transportation route for the parts becoming longer and the production lead time also becoming longer. The present invention provides an apparatus that is equipped with a chain-type magazine, compactly stores a large amount of setup members such as jigs, and has high magazine indexing accuracy.

0004

[Means for Solving the Problems] A lathe cell is a lathe cell that provides a lathe for combined machining, a workpiece storage device and a setup member storage device that are arranged adjacent to the lathe for combined machining, and a lathe for workpieces between the lathe for combined machining and the storage device. It is equipped with a conveyance device that conveys setup materials, etc. The setup member storage device has a base disposed in a direction perpendicular to the transport rail, and includes a stocker that linearly runs on the base. The stocker stores a hand that is replaceably attached to the arm of a transporting robot. Two jig storage devices are installed on both sides of the base. The tool storage device has two chains running in parallel between a driving sprocket wheel and a driven sprocket wheel, and a tool magazine is provided between the two chains. A jaw magazine is formed on the side of one chain. The chain spans between a driving sprocket wheel and a driven sprocket wheel. A driven sprocket wheel for position detection is disposed between the driving sprocket wheel and the driven sprocket wheel, and a service position for exchanging tools and jaws is disposed above the sprocket wheel.

[0005]

[Operation] The first jig and tool storage device is the first tool storage device of the compound machining lathe.
The jaws and tools are supplied to the main shaft and the first tool rest, and the second
The jig and tool storage device supplies jaws and tools to the second spindle and the second tool post. Since the amount of movement of the chain is detected by a position detecting driven sprocket disposed at the service position, the tool magazine and jaw magazine can be indexed with high precision.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view of a lathe cell according to the present invention, and FIG. 2 is a front view thereof. The lathe cell, designated as a whole by reference numeral 1, includes a composite processing lathe 10, a work storage device 50, a setup member storage device 30, and a conveyance device 20. The compound machining lathe 10 is, for example, of the type proposed in the present application and disclosed in Japanese Patent Publication No. 2-42602. This type of compound machining lathe is equipped with two main spindles arranged opposite to each other and a tool rest that cooperates with each main spindle. 1st
The main spindle and the first tool rest cooperate to perform the first process on the workpiece gripped by the first main spindle. The second spindle receives the workpiece that has been processed in the first step from the first spindle, and cooperates with the second tool post to process the workpiece in the second step. All machining of the workpiece is completed through a series of machining steps. Therefore, highly processed workpieces can be produced in a short time and with high precision. A workpiece storage device, generally indicated by the reference numeral 30, and a setup member storage device, indicated by the reference numeral 50, are disposed on the side of the compound machining lathe 10.

In the illustrated embodiment, the setup member storage device 50 is disposed on the side of the compound machining lathe 10, and the workpiece storage device 30 is disposed on the outside thereof. However, this setup member storage device 50 and workpiece storage device 30
They may be separated and placed on both sides of the combined machining lathe 10. Further, the setup member storage device 50 and the workpiece storage device 30 can be disposed on either side of the compound machining lathe. A conveyance device 20 is provided at the top of the multi-tasking lathe 10 to connect it to a workpiece storage device 30. The transport device 20 includes a guide rail 200 and a guide rail 20
A gantry robot 210 is provided that runs along an axis B, which is the longitudinal axis of the robot. Gantry robot 2
Reference numeral 10 indicates an arm 220 that moves up and down along an axis A that is a vertical direction, and a hand 250 that is installed at the tip of the arm 220.
has. The hand 250 is replaceable, and various types of hands are available depending on the workpieces and jigs to be handled. The structure and function of the conveying device 20 in the lathe cell are disclosed in Japanese Patent Application No. 2-2733925 filed by the present applicant. The work storage device 30 includes a guide rail 200
It has a base 300 disposed in a direction perpendicular to . A trolley 310 is attached to the base 300 in a movable manner. The trolley 310 is a loading station WS1 for pallets loaded with workpieces, and a station WS2 for loading pallets.
It moves back and forth between.

[0008] Work pallet 35 carrying work 360
0 are carried into the carry-in station WS1 in a stacked state. The traveling truck 310 includes a fork device 320. The fork device 320 is supported movably in the vertical direction with respect to the traveling carriage 310. The arms of the fork device 320 grip the work pallet 350 from both sides. The work pallet 350 is provided with a memory element, and information about the placed work is written therein. The fork device 320 is a work pallet 35
A device for reading data from a 0 storage element is provided. When the stacked pallets are delivered to the delivery station WS1,
The fork device 320 moves up and down along the stacked pallets 350, reads information on the workpieces on each pallet, and sends it to the controller 90. The controller 90 instructs the conveyance device 20 and the multi-tasking lathe 10 to perform machining procedures and the like based on information about the workpiece that has been carried in. The traveling truck 310 and the fork device 320 transport the pallet 350 carrying the workpiece to a service position set directly below the guide rail 200, and work together with the gantry robot 210 to supply the corresponding workpiece 360 to the multi-tasking lathe 10. . The workpiece that has been processed by the multi-tasking lathe 10 is placed on the workpiece pallet 3.
Returned to 50. When all the workpieces on one pallet 350 are processed, the traveling truck 310 and the fork device 3
20 unloads the work pallet 350 to the unloading station WS2. Thereafter, the pallets 350 loaded with material workpieces are sequentially transported to the service position to continue processing.

The compound machining lathe 10 is capable of machining workpieces of various shapes and sizes. Depending on the type of workpiece, it is necessary to change the setup of the chuck of the spindle, tools, etc. The lathe cell 1 of the present invention includes a device for accommodating a large number of setup members. The setup member storage device 50 includes a base 500 disposed in a direction perpendicular to the guide rail 200 of the conveyance device 20 . A rail 502 is provided on the base 500, and a stocker 510 is attached movably along the axis X5. The stocker 510 has a box-like shape with an open top, and the exchange hand 250 is stored inside the stocker 510. The exchange hand 250 is exchangeably attached to the tip of the arm 220 of the gantry robot 210. Types of the hand 250 include a tool hand that handles tools that are supplied to the tool rest of the multi-tasking lathe 10, a jaw hand that handles the jaw that is supplied to the chuck of the main spindle of the multi-tasking lathe 10, and a work hand that handles a workpiece. Work hands include a scroll chuck type hand that grips the end face of a workpiece and a work hand that grips the outer periphery of a bar workpiece. In a scroll chuck type work hand, it is necessary to replace the jaws of the hand depending on the diameter of the work. Stocker 5
Hand jaw set 26 stored in the flange surface of 10
0 is provided with a jaw set corresponding to the geometry of the workpiece and is replaced with a workhand. Both side fixtures of the base 500 of the setup member storage device 50 are equipped with large-capacity jig and tool storage devices.

FIG. 3 is a plan view of the tool storage device, FIG. 4 is a front view, and FIG. 5 is a side view. The tool storage device 60 has two chains 630 and 640 arranged in parallel. The two chains 630, 640 are threaded around a pair of chain sprocket wheels 610, 620 attached to opposite ends of the base 500. The first chain sprocket wheel 610 is the drive wheel and the second
The chain sprocket wheel 620 is a driven wheel. Drive wheel 610 is controlled by a servo motor 612. Drive wheel 610 and driven wheel 6
A service position SP for exchanging tools and jaws is set approximately in the center of the machine 20. Service position SP
A driven sprocket wheel 615 is provided at the bottom of the chain, and the amount of rotation of the wheel 615 is detected by an encoder to position the chain. The diameters of the wheels 610, 620 have large dimensions and a large radius of curvature. Therefore, the overall height H of the tool storage device 60 increases. The two tool storage devices 60 provided on both sides of the base 500 have symmetrical structures sandwiching the center line of the base 500.

FIG. 6 is a plan view showing the main parts of the tool storage device, and FIG. 7 is a side view. One chain 630 has plates 632 on both sides of links 631, and pins 63
It has a structure in which 3 are connected. The other chain 640 has a similar structure. Tool holder 65 for holding tools
0 has a board-like structure that connects the left and right chain links. A tool pocket 651 into which a tool 710 is inserted is provided in the center of the tool holder 650. The tool pocket 651 is the cylindrical shank 7 of the tool 710.
It has a cylindrical structure into which 12 is inserted. Serrations 713 are formed on the outer periphery of the tool shank 712. The tool holder 650 has a shaft 653 with serration grooves at the tip, and the shaft 653 has a cam follower 6.
55 to move in the axial direction. The serrations at the tip of the shaft 653 mesh with the serrations 713 of the tool shank 712 to form a receiving part for the tool 710. An ID antenna 790 is installed at a predetermined position on the base 500, and tool information written on an ID tag embedded in the tool holder 650 is read or written. A jaw holder 660 is attached to the side of the second chain 640 disposed inside. A jaw holder 660 is provided for each link of the chain. In this example, 100 jaw holders 660 are provided. Jaw holder 660 is Jaw 7
20 into the jaw pocket 661.

As described above, according to the present invention, the setup member storage device attached to the lathe is equipped with the first and second jig storage devices. The first tool storage device can store 50 tools and 100 jaws. The tool is fed to the first turret of the multitasking lathe. The jaws are fed into the chuck of the first spindle of the multitasking lathe. Generally, a spindle chuck is used as a set of three jaws. This jig and tool storage device can store 100 jaws, but a total of 99 jaws are stored in 33 sets, and one jaw holder is left empty. This empty jaw holder 665 can be used as the origin of a chain-type tool storage device. Since this device can accommodate a large number of tools and jaws, the lathe cell can continue unmanned production of a wide variety of workpieces for long periods of time. The tool magazine and jaw magazine constituting the tool storage device 60 of the present invention exchange tools and jaws at a service position set above the circulating chain. Therefore, at the bottom of the chain, the tools and jaws are subjected to a downward force and a force in the direction of pulling them out of the tool pocket or jaw pocket. Therefore, a mechanism is required to prevent the tool or jaw from slipping out of the pocket.

FIG. 8 is an explanatory diagram showing the operation of the jaw magazine. The jaw magazine, generally designated by the reference numeral 70, is controlled to move in the forward direction P1 or in the reverse direction P2. A service position SP for replacing jaws is set at the upper center of the path of the jaw magazine 70. At this service position SP, the jaw hand of the gantry robot pulls out a predetermined jaw 720 of the jaw magazine 70 from the magazine and returns it to the magazine. Therefore, the detachment prevention device provided in the jaw magazine 72 is
In the vicinity of the service position SP, the jaw is unclamped to allow the jaw to be pulled out of the pocket, and in other areas it is clamped to prevent the jaw from coming out of the pocket. As a mechanism for operating the retaining device, a first guide G1 is provided at the service position SP, and a first dog 11 and a second dog 12 are provided on the upstream and downstream sides of the guide G1. When the jaw magazine 70 moves in the forward direction P1, an unclamping range UC1 is set between the guide G1 and the first dog D11. When the jaw magazine 70 moves in the reverse direction P, an unclamping range UC2 is set between the guide G1 and the second dog D12.

FIGS. 9, 10 and 11 show details of the jaw retaining device. The retaining device, which is generally designated by the reference numeral 670, has a plate-shaped bracket 672 that is rotatably attached to the jaw pocket 661 by a pin 671. The upper end of the bracket 672 has an inwardly bent portion 67.
3 is formed, and a cam follower 674 is attached to the lower end. The center of gravity of the bracket 672 is set at a position where the bracket 672 stands upright in its natural state so as to maintain a clamped state when the jaw pocket faces downward. Accordingly, the bend 673 at the upper end of the bracket 670 engages the shoulder 724 of the jaw 720 and prevents the jaw 720 from slipping out of the jaw pocket 661. Figure 12
9 is a plan view of the guide G1 and the two dogs D11 and D12. FIG. The guide G1 is made of a plate-like material 680 and has a cam groove 681. This cam groove 681 is connected to the cam follower 6 of the retaining prevention device 670.
74 in the direction of the arrow. FIG. 11 is a view taken in the direction of arrow B in FIG. 9, showing a state in which the retaining device 670 rotates in the direction of the arrow, and the bent portion 673 is removed from the shoulder portion 724 of the jaw 720. In this state, the jaw 720 can be pulled out upward. When the cam follower 674 comes off the cam groove 681 of the guide G1 and is guided by the first dog D11, it returns to the clamped state. The first dog D11 has a main body 685 made of a plate-like material, and forms a chevron-shaped cam crest 686. When the cam follower 674 of the retainer 670 hits this cam ridge 686, the cam action forces the retainer 670 to return to the clamped state.

Since the jaw magazine of the present invention is equipped with the fall prevention device as described above, the chain-type jaw magazine can be freely rotated within a vertical plane. Next, the tool drop prevention device will be explained with reference to FIGS. 13 to 17. The pocket 651 of the tool magazine has a cylindrical shape into which the shank 712 of the tool 710 is inserted. A shaft 653 is slidably attached to this tool pocket 651. A tool shank 71 is attached to the tip of the shaft 653.
Serrations 654 that engage with the serrations 713 of No. 2
is formed. This shaft 653 is the cam follower 65
5. The service position SP in the tool magazine is set near the service position SP of the jaw magazine. A guide G2 is provided at the service position SP, and a first dog D21 and a second dog D22 are provided on the upstream and downstream sides of the guide G2. The guide G2 has a main body 690 made of a plate-like material, and cam ridges 691 are formed at the front and rear of the main body 690. The first dog D21 has a main body 695 made of a plate-like material, and the main body 695 has a cam ridge 696.
has. The second dog D22 has a similar body 697, and the body 697 forms a cam ridge 698.

FIGS. 13 and 14 show tool 710 clamped within tool pocket 651. FIG. The shaft 653 comes into contact with the tool shank 712, and the serrations are engaged and the tool 710 is inserted into the tool pocket 651.
prevent it from falling. When the tool magazine approaches the service position SP, the cam ridge 691 of guide G2
The cam follower 655 rides up and pulls the shaft 653 away from the tool shank 712. FIGS. 15 and 16 show this state. Serrations 654 of shaft 653 disengage from serrations 713 of tool shank 712, allowing tool 710 to exit tool pocket 651. When passing through the service position, the cam follower 655 is pressed toward the tool shank 712 by the cam ridge 696 of the first dog D21, and the serrations of both are engaged to return to the clamped state. Therefore, even if the tool magazine moves downward, the tools are prevented from falling. Since the tool magazine of the present invention is equipped with the tool fall prevention device as described above, the tool magazine on the chain can be freely run in a vertical plane. The present invention constructs a large-capacity jig and tool storage device by forming a tool magazine and a jaw magazine using a chain in which a large number of links are connected endlessly as described above.

[0017] When exchanging tools or jaws stored in a magazine, a designated magazine is indexed to the service position SP. At the service position SP, the hand of the gantry robot automatically performs the process of pulling out tools and jaws from the magazine and putting them back in. Therefore, it is necessary to accurately position the designated magazine on the service position SP. With use, the chain stretches and backlash between the chain and the sprocket causes positioning errors. Therefore, in order to index the chain to a predetermined position, it is necessary to take these factors into consideration. A possible solution to this problem is to set a service position directly above the driving sprocket wheel or driven sprocket wheel over which the chain is passed. However, in this layout, the jig and tool storage device largely protrudes in one direction with respect to the axis of the transport rail, which poses a problem when increasing the capacity of the jig and tool storage device. Therefore, in the present invention, as described above, a driving sprocket and a driven sprocket are provided, the amount of movement of the chain is detected by this second driven sprocket, and a service position is provided above the driven sprocket.

FIG. 18 is a plan view showing the vicinity of the service position SP provided in the center of the tool storage device 60.
9 is a front view, and FIG. 20 is a side view. As explained in FIG. 4, the chain 630 constituting the tool storage device is connected to the driving sprockets 610 installed at both ends of the base 500.
A service position SP is set above a second driven sprocket 615 that spans between the driving sprocket 610 and the driven sprocket 620 and is provided at an intermediate portion between the driving sprocket 610 and the driven sprocket 620. sprocket 615
is attached to a shaft 616, and the shaft 616 is supported by a bearing bracket 550 mounted on the base 500 via a bearing 552. A rotary encoder 560 is attached to the end of the shaft 616 to accurately detect the amount of rotation of the sprocket 615. Therefore, the driven sprocket 615 functions as a position detection sprocket. Servo motor 612 that operates drive sprocket 610 performs positioning control based on information from encoder 560. When the valley 615A of the sprocket 615 reaches just above the rotation center C1 of the sprocket 615, the tool pocket,
The center position of the jaw pocket is configured to coincide with the service position SP.

In this position, the pin 643 of the chain link is securely engaged with the sprocket 615A, and backlash with the chain can be eliminated. Therefore, the accuracy of indexing the chain magazine is improved. Furthermore, the rotation center C1 of the sprocket 615
The contact pressure is increased by lifting the chain link pin 643 by about 0.1 mm from the chain travel path when the valley 615A reaches the top. With this configuration, backlash between the sprocket 615 and the chain can be further reduced. In addition, service position S
A chain holding device 577 is installed near point P to hold down the upper part of the chain to prevent the chain from lifting up and ensure the engagement of the sprockets. Since the sprocket 615 is driven by the chain, it tends to continue rotating due to inertia even when the chain stops at the commanded position. Due to this action, the encoder detects that the sprocket has overrun by the amount of backlash between the chain and sprocket, and issues a command to the servo motor to return the chain. This phenomenon causes so-called hunting, in which the sprocket repeatedly goes too far and returns too far from the commanded position.

In the present invention, a mechanism for preventing hunting is provided on the sprocket. sprocket 6
15 is provided with four through holes, a spring 572 is inserted into the through hole, and a sliding pin 5 is inserted at both ends of the spring 572.
70 has been inserted. When the sprocket 615 rotates, the pin 572 is attached to the fixed side brackets 550 on both sides.
, 554, and brakes the rotation of the sprocket 615. This braking force prevents the sprocket from overrunning and hunting does not occur. The tool storage device of the present invention includes a chain tension device on the driven sprocket 620 side that absorbs the elongation of the chain and keeps the tension of the chain constant.

FIG. 21 is a plan view of the chain tension device, and FIG. 22 is a front view. The chain tensioning device, generally designated by the reference numeral 580, has a fixed bracket 581 fixed to the base 500 and a sliding bracket 586 slidably supported by the fixed bracket 581. A shaft 622 is installed in the sliding bracket 586, and a driven sprocket 6 is connected to the shaft 622 via a bearing 621.
20 is rotatably supported. The adjustment bolt 58 is attached to the block 582 fixed to the end of the fixed bracket 581.
3 and secure with nuts 583. Adjustment bolt 58
3 supports a moving block 585. Two shafts 587 attached to the moving block 585 are inserted into holes in the sliding bracket, and a spring 588 is disposed between them. This spring 58
8 biases the sliding bracket 586 in the direction away from the moving block 585. The direction in which the sliding block is biased is
This corresponds to the direction of pulling away from the sliding sprocket 610 and provides tension to the chain. As described above, by providing the chain tension device 580, it is possible to always apply appropriate tension to the chains that constitute the magazine. Therefore, even if the chain stretches due to use, the stretch is automatically absorbed and no adjustment work is required. Therefore, production efficiency can be improved and maintenance labor can be reduced.

[0022]

[Effects of the Invention] As described above, the present invention allows the storage device for tools and jaws to be configured with a large capacity, so it is possible to continue unmanned machining for a long time with sufficient spare tools and spindles. can. The compound machining lathe includes a first spindle and a first tool rest, and a second spindle and a second tool rest. The jig and tool storage device of the present invention includes a tool magazine for accommodating tools and jaws to be supplied to a first spindle and a first tool rest, and a tool magazine for accommodating tools and jaws to be fed to a second spindle and a second tool rest. Since the tool magazine and the jaw magazine that house the tools are configured separately and each is controlled independently, the tools and jaws can be replaced in a short time. The tool magazine and jaw magazine are constructed using an endless chain. The chain runs between a driving sprocket and a driven sprocket mounted on the base, and by locating a service position in the middle of both sprockets, the entire lathe cell can be laid out rationally. In the service position, a driven sprocket for position detection is provided, and the position of the chain is detected based on the amount of rotation of the sprocket. At this time, the service position is set based on the rotational position of the sprocket where the contact between the chain and the sprocket is stable, so the position detection accuracy is improved, and means is provided to increase the contact pressure between the chain and the sprocket. Furthermore, a brake is provided on the driven sprocket for position detection to prevent overrun. This prevents hunting from occurring and achieves highly responsive detection. Since a chain tension device is provided at the attachment part of the driven sprocket, appropriate tension is always applied to the chain, achieving maintenance-free and smooth operation.

[Brief explanation of drawings]

FIG. 1 is a plan view of a lathe cell implementing the present invention.

[Fig. 2] Front view.

FIG. 3 is a plan view of the setup member storage device.

FIG. 4 is a front view.

FIG. 5 is a side view.

FIG. 6 is a plan view of a tool magazine and a jaw magazine.

FIG. 7 is a cross-sectional view.

FIG. 8 shows the travel path of the tool magazine.

FIG. 9 is a front view showing details of the jaw magazine.

FIG. 10 is a view in the direction of arrow A in FIG. 9;

FIG. 11 is a view taken along arrow B in FIG. 9;

FIG. 12 is a view along arrow C in FIG. 9;

FIG. 13 is a cross-sectional view of the tool magazine.

FIG. 14 is a BB sectional view of FIG. 13.

FIG. 15 is a cross-sectional view of the tool magazine.

FIG. 16 is a sectional view taken along line AA in FIG. 15;

FIG. 17 is an explanatory diagram showing the action of the tool fall prevention device.

FIG. 18 is a plan view of the area around the service position of the tool storage device.

FIG. 19 is a plan view.

FIG. 20 is a side view.

FIG. 21 is a plan view of the chain tension device.

FIG. 22 is a front view.

[Explanation of symbols]

1 Lathe cell 10 Combined processing lathe 20 Transport device 30 Workpiece storage device 50 Setup member storage device 60 Jig storage device 70 Jaw magazine 72 Tool magazine 500 Base 560 Rotary encoder 570 Brake pin 580 Belt tension device 610 Drive sprocket 615 Position detection driven Sprocket 620 Driven sprocket 710 Tool 720 Jaw

Claims (8)

[Claims] Claim 1: A compound machining lathe, a workpiece storage device and a setup member storage device arranged adjacent to the compound machining lathe, and a device for transporting components between the compound machining lathe and the workpiece storage device and setup component storage device. A jig and tool storage device that is installed in a setup member storage device of a lathe cell that is equipped with a conveyance device, and the jig and tool storage device includes a chain that is stretched between a driving sprocket wheel and a driven sprocket wheel that are supported on a base. It has a tool magazine and a jaw magazine arranged on the chain, and a driven sprocket wheel for position detection is arranged in the middle part between the driving sprocket wheel and the driven sprocket wheel, and a tool magazine is arranged on the upper part of the driven sprocket wheel for position detection. A jig and tool storage device for a lathe cell, which has a service position for replacing jaws. 2. Claim 1, further comprising means for controlling a servo motor that drives a drive sprocket wheel based on a signal from a rotary encoder attached to a position detecting driven sprocket and detecting the amount of movement of the chain.
A jig and tool storage device for the lathe cell described. 3. The tool storage device for a lathe cell according to claim 1, wherein the position detecting driven sprocket is provided with a brake device for preventing overrun. 4. The tool storage device for a lathe cell according to claim 1, further comprising means for increasing the contact pressure between the position detecting driven sprocket and the chain. 5. The lathe cell according to claim 4, wherein the means for increasing the contact pressure is means for positioning the rotation center of the position detecting driven sprocket at a position where the chain is pushed upward at the center position of the position detecting driven sprocket. jigs and tools storage device. 6. The tool storage device for a lathe cell according to claim 4, wherein the means for increasing the contact pressure is a pressing means for pressing the upper surface of the chain. 7. The tool storage device for a lathe cell according to claim 1, wherein the driven sprocket wheel is attached to the base via a chain tension device that applies tension to the chain. 8. The chain tension device includes a fixed bracket fixed to a base, a sliding bracket slidably supported by the fixed bracket and rotatably supporting a driven sprocket, and a fixed bracket and a driven bracket. 8. The tool storage device for a lathe cell according to claim 7, further comprising a spring disposed between the lathe cells.