JP4769285B2 - Tool breakage detector - Google Patents

Description

  The present invention relates to a tool breakage detection apparatus provided in a machine tool system including a machine unit for machining a workpiece and a tool stocker for storing a plurality of tools used in the machine unit.

  In general, a machine tool system that includes a tool stocker that holds a plurality of detachable tools and performs various types of machining on a workpiece while exchanging tools mounted on a machining spindle of a machine unit is used.

  In such a system using a large number of tools, it is important to keep track of the state of each tool in terms of maintenance of smooth and automatic processing, cycle time, and the like. For example, when a tool breaks due to seizure or the like during processing, it is desirable to detect the breakage quickly and replace the tool as necessary in order to avoid system stoppage or the like as much as possible.

  Therefore, regarding a device for detecting breakage of a tool, Patent Document 1 discloses that a machining head (gang head) that rotatably supports a plurality of machining spindles is mounted on a slide unit and moved to a machining position to machine a workpiece. An apparatus in which a tool breakage detection device is mounted on a turret device to be performed is disclosed. This turret device is a system in which four machining units each having a plurality of tools are arranged in four directions around a turning axis, and each machining unit is turned and indexed. And while processing with respect to a workpiece | work with the processing unit indexed to the downward position, the said tool breakage detection apparatus is arrange | positioned corresponding to the processing unit indexed to the upper position facing this.

Japanese Patent No. 3369712

  By the way, the tool breakage detection apparatus described in the above-mentioned patent document 1 detects collectively the breakage of a plurality of tools arranged in a predetermined processing unit of the turret device.

  Therefore, in the turret device, if the numbers A to D are assigned in order from the lower processing unit that processes the workpiece, the upper processing unit corresponding to the tool breakage detection device is C. In this case, after the desired machining unit A is indexed to the lower position and the workpiece is machined, machining is performed by the machining unit B adjacent to the workpiece, and then drive control is performed such that machining is performed again by the machining unit A. The processing unit A cannot reach the tool breakage detection device over a plurality of cycles. For example, even if the tool is broken in the first machining, there is a possibility that the processing unit A is continuously used without being detected. In other words, tool breakage is not detected at all when machining is continued with only a predetermined machining unit without rotating the pivot axis.

  On the other hand, it is conceivable to detect breakage of a tool by rotating the turret every time one model is processed by a predetermined processing unit, but the system is substantially stopped for a long time and the cycle time is extended. .

  The present invention has been made in consideration of the above-described conventional problems, and is capable of detecting tool breakage quickly and avoiding system stoppage as much as possible to improve production efficiency. The purpose is to provide.

  A tool breakage detection device according to the present invention stores a plurality of work units that are mounted with a detachable tool to process a workpiece, and a plurality of the tools that can be exchanged with the work unit, and the tool is determined by a rotating operation. A tool breakage detection device for a machine tool system comprising a plurality of tool stockers, wherein the tool breakage detection device is capable of simultaneously approaching at least one of the tools stored in each tool stocker. A bracket provided with a plurality of tool approaching portions, a plurality of non-contact or contact-type detectors provided at each tool approaching portion for detecting breakage of the tool, and the bracket moving in the axial direction of the tool And a moving mechanism.

  According to such a configuration, breakage detection can be performed simultaneously on the tools stored in the plurality of tool stockers, and further, breakage detection of the tool can be performed even during machining by the machine unit. Therefore, tool breakage can be detected quickly, and since detection is possible at the time of machining, system stoppage can be avoided as much as possible, and production efficiency can be improved.

  In addition, the tool approach portion is a tool having the shortest and longest axial length among the tools stored in the tool stocker in a state where the tool is in a position closest to the tool by the moving mechanism. If the structure does not interfere, the same tool approaching part can be made to correspond to the detection of breakage of all length tools used.

  In this case, the detector has the shortest and longest axes among the tools stored in the tool stocker when the tool approaching portion is moved from the position closest to the tool to the position farthest away from the tool. If the breakage of the tool having the directional length is fixed at a position where the breakage can be detected, it is possible to reliably detect the breakage of the tools having all the lengths used.

  Furthermore, when the tool stocker is rotated in a state where the tool approaching portion is located closest to the tool by the moving mechanism, the tool approaching portion has a structure that does not interfere with a tool stored in the tool stocker. Even when breakage is detected on the one tool stocker side, the other tool stocker can be rotated, for example, automatic tool change to a machine unit or the like.

  Furthermore, the tool approaching portion is a position that can be handled in a state in which the tools stored in at least two tool stockers among the plurality of tool stockers are indexed to the closest positions by the rotation operation. The tool breakage detection device can be made as small as possible.

  According to the present invention, by providing a tool approaching unit and a detector that can simultaneously handle at least one tool stored in each of a plurality of tool stockers, it is possible to simultaneously detect breakage of the tools of each tool stocker. In addition, tool breakage can be detected even when machining is being performed by the machine unit. Therefore, breakage of the tool can be quickly detected, and since the detection can be performed at the time of machining, the system stop can be avoided as much as possible, and the production efficiency can be improved.

  Hereinafter, a preferred embodiment of a tool breakage detection apparatus according to the present invention will be described in detail in relation to a machine tool system equipped with the tool breakage detection apparatus, with reference to the accompanying drawings.

  FIG. 1 is a partially cutaway perspective view of a machine tool system 10 equipped with a tool breakage detection apparatus 200 according to an embodiment of the present invention. FIG. 2 is a front view of the machine tool system 10 shown in FIG. FIG. 3 is a side view of the machine tool system 10 shown in FIG. The machine tool system 10 performs drilling, boring, honing and the like on the workpiece W. Hereinafter, in order to specify the direction of the machine tool system 10, the left-right direction in FIG. 2 is the X direction (X1, X2 direction), the height direction is the Y direction (Y1, Y2 direction), and the X direction and the Y direction are The orthogonal depth direction is defined as the Z direction (Z1, Z2 direction) (see FIG. 3). The X direction and the Y direction are predetermined one direction in the horizontal plane and are orthogonal to each other.

  The machine tool system 10 includes a first machine tool 10a on the left side (arrow X1 side), a second machine tool 10b on the right side (X2 side), and the first machine tool 10a and the second machine tool 2 in the front view shown in FIG. And a controller 12 that controls the machine tool 10b in an integrated and cooperative manner. Further, above the first machine tool 10a and the second machine tool 10b (Y2 side), two tool stockers (tool stockers) 80a and 80b for holding a plurality of detachable tools T corresponding to the two machines, respectively. Is provided, and a tool breakage detection device 200 is disposed between the tool stockers 80a and 80b.

  As shown in FIGS. 1 and 2, a first machine tool 10 a and a second machine tool 10 b that constitute a machine unit that is mounted with a detachable tool and processes a workpiece W are provided in parallel and adjacent to each other. The surface plate 13, the workpiece moving device 14 and the frame 15 are shared. The surface plate 13, the workpiece moving device 14, and the frame 15 may be dedicated to the first machine tool 10a and the second machine tool 10b. In the present embodiment, the first machine tool 10a and the second machine tool 10b have the same structure, and the first machine tool 10a will be representatively described below.

  The first machine tool 10a is configured based on a surface plate 13 fixed to the floor. The surface plate 13 is narrow in the X direction and low in the Y direction. A workpiece moving device 14 and a frame 15 are attached to the upper surface of the surface plate 13.

  The workpiece moving device 14 includes workpiece tables 19a to 19c provided on the front side (arrow Z1 side) of the upper surface of the surface plate 13. Above the workpiece moving device 14, workpiece pressing and fixing devices 17a and 17b (see FIG. 3) for pressing and fixing the workpiece W placed on the workpiece tables 19a to 19c from above are provided. In the case of this embodiment, the work tables 19a to 19c are configured as rotating tables arranged at intervals of 120 °. 1, 2, and 5, the work pressing and fixing devices 17 a and 17 b are omitted so that a support 22, a rotating arm 32, and the like described later can be visually recognized.

  As shown in FIG. 1, the frame 15 includes tool stockers 80a and 80b, which are tool stockers that store (hold) a plurality of tools T, and a tool breakage detection device 200 that can simultaneously handle both tool stockers 80a and 80b. It is supported. That is, the tool stockers 80a and 80b and the tool breakage detection device 200 are configured as units independent of the first machine tool 10a and the second machine tool 10b, which are machine units, and outside the machining section having the machine units. Yes, it is protected from cutting waste and cutting oil during processing of the workpiece W by a plate 15b and the like which will be described later.

  The frame 15 includes four support columns 15a extending upward from both ends of the surface plate 13 in the arrow Z direction, and plates 15b supported by the upper portions of the support columns 15a. In addition, two sets of two support columns 15a in the Z direction constituting the frame 15 are provided, and a shutter 107 is provided between the two support columns 15a, and the shutter 107 is provided in each set. When the workpiece W is processed, the shutter 107 prevents cutting waste and cutting oil from scattering left and right outside the apparatus. The shutter 107 is opened during maintenance of the machining spindle 36 that performs machining on the workpiece W with the tool T.

  The first machine tool 10a includes a pair of Z rails 16 and 16 provided on the upper surface of the surface plate 13 and extending in the Z direction, a column 18 guided by the Z rail 16 and slid in the Z direction, It has a pair of Y rails 20 and 20 that extend in the Y direction on the front surface, and a support body 22 that is guided by the Y rails 20 and slides in the Y direction (see FIG. 2). The Z direction position of the column 18 on the Z rail 16 is detected by the Z position sensor 16a, and the Y direction position of the support 22 on the Y rail 20 is detected by the Y position sensor 20a (see FIG. 2). 12 is supplied.

  The column 18 reciprocates in the Z direction via a ball screw mechanism 26 under the action of a Z motor 24 provided behind the surface plate 13 (see FIG. 3). A rotary encoder (not shown) is attached to the Z motor 24, and the rotary encoder detects the rotation angle of the ball screw of the ball screw mechanism 26. The detected rotation angle of the ball screw is determined as the Z-direction position of the column 18. , It may be configured to be transmitted to each controller 12.

  The support 22 reciprocates in the Y direction via the ball screw mechanism 30 under the action of the Y motor 28 disposed inside the surface plate 13 (see FIG. 2). Further, a rotary encoder (not shown) is attached to the Y motor 28, the rotation angle of the ball screw of the ball screw mechanism 30 is detected by the rotary encoder, and the detected rotation angle of the ball screw is detected as the Y-direction position of the support 22. May be transmitted to each controller 12. Note that the column 18 and the Y rail 20 have a reasonably long shape in the Y direction, and can move the support 22 for a relatively long distance.

  As shown in FIG. 4, the support 22 includes a rotary arm 32 that rotates (turns) in a vertical plane (XY plane) facing the workpiece W facing in the Z1 direction, and an arm motor 34 that rotates the rotary arm 32. The machining arm 36 is provided near the end of the rotation arm 32 in the centrifugal direction, is rotatably supported by the rotation arm 32 and faces the Z1 direction, and a spindle motor 38 that rotates the machining spindle 36. The arm motor 34 is, for example, a direct motor. The support body 22 is configured based on a frame body 40, and an arm motor 34 is provided inside the frame body 40. The arm motor 34 has a stator 34a fixed to the frame body 40 and a hollow rotor 34b provided inside the stator 34a.

  The rotary arm 32 is fixed to the end of the rotor 34b on the arrow Z1 side, and rotates under the action of the arm motor 34. The angle of the rotary arm 32 with respect to the support 22 is measured by an angle sensor 41 (see FIG. 1) and supplied to the controller 12.

  As can be understood from FIG. 4, the rotary arm 32 can be rotated endlessly, but it is sufficient that the rotary arm 32 can rotate at least once (360 degrees). The machining spindle 36 is provided at a location separated from the rotation center C1 of the rotary arm 32 by a distance R.

  In the rotary arm 32, a balancer 42 is provided on the opposite side (upper side in FIG. 4) to the side where the machining main shaft 36 is provided. The balancer 42 is a liquid tank containing a liquid such as coolant, and can balance by changing the amount of liquid inside according to the tool attached to the machining spindle 36. The balancer 42 may be a metal weight. The inside of the rotary arm 32 other than the portion where the balancer 42 is provided has a hollow structure. The rotary arm 32 is considerably lighter than the support body 22, and does not impair the stability of the support body 22 and the first machine tool 10a when rotated.

  The spindle motor 38 protrudes in the direction of the arrow Z2, and is fixed to the rear surface of the frame body 40 in the support body 22 so as to be coaxial with the arm motor 34. Thus, by arranging the spindle motor 38 and the arm motor 34 coaxially, the support 22 can be configured as a compact unit. That is, if the spindle motor 38 does not exist on the axis of the machining spindle 36 and the spindle motor 38 is located near the center of the rotating arm 32, the mass and size of the balancer 42 can be reduced, and the support 22 can be reduced. Can be made compact as a whole.

  The shaft 44 is provided through the hollow portion of the rotor 34 b, one end is fixed to the rotating shaft of the spindle motor 38, and the other end protrudes from the frame body 40 and reaches the side plate on the arrow Z <b> 1 side of the rotating arm 32. . The shaft 44 is pivotally supported by bearings 45a, 45b, and 45c in order at three locations, the arrow Z1 side end portion and the arrow Z2 side end portion of the rotating arm 32, and the arrow Z2 side end portion of the frame body 40.

  The pulley mechanism 46 includes a drive pulley 46a that is fixed to the shaft 44 between the bearings 45a and 45b, a driven pulley 46b that is fixed to an end in the arrow Z2 direction of the machining main shaft 36, and the drive pulley 46a and the driven pulley. The belt 46c is stretched between the belt 46b and the belt 46b. Thus, the drive mechanism using a pulley is suitable because the rotating arm 32 can be reduced in weight. In addition to the drive mechanism using a pulley, for example, the drive pulley 46a may be replaced with a gear, and the driven pulley 46b may be replaced with a pinion, and a drive transmission mechanism using a silent chain may be used. In this case, the driving force may be transmitted between the gear and the pinion via a plurality of gears.

  The pulley mechanism 46 is provided in a hollow portion in the rotary arm 32, and the tension of the belt 46c is adjusted by a predetermined tension mechanism. With such a structure, the rotation of the spindle motor 38 is transmitted to the machining spindle 36 via the shaft 44 and the pulley mechanism 46.

  The machining spindle 36 is accommodated in a spindle cover 48 that is provided integrally with the rotary arm 32, and a tool head 50 to which a tool T is mounted is provided at the tip in the direction of the arrow Z1. In addition, an unclamp lever 52 that releases the tool T from the tool head 50 and allows the tool T to be detached is provided at the end in the direction of the arrow Z2. The unclamp lever 52 has a shape that slightly protrudes outward as viewed from the rotation center C1, and is operated by being pressed in the direction of the rotation center C1 by an unclamp block 53 (see FIG. 6), thereby unclamping the tool T. Can be clamped. Further, the unclamping lever 52 is returned to the original position by an elastic body (not shown) when the unclamping block 53 is separated, and the tool T in the tool head 50 can be clamped. Of course, the clamping and unclamping of the tool T by the tool head 50 may be a mechanism for clamping the tool T electrically.

  On the back side (Z2 side) of the rotary arm 32, a fixing device 64 is provided that clamps the disc 62 made of a leaf spring or the like with a screw 60 to fix the rotary arm 32 at a predetermined position. The fixing device 64 includes a receiving seat 66 that contacts the back side of the disc 62, and a pressing piece 68 that holds the disc 62 between the receiving seat 66. The pressing piece 68 is provided at the tip of a rod 72 biased in the clamping direction by a disc spring 70, and the rod 72 is pushed forward against the disc spring 70 to release the clamping state of the disk 62, thereby rotating the arm. 32 rotations are possible. In the case of the present embodiment, since the disk 62 is configured by a leaf spring, the rotating arm 32 does not fall down while the disk 62 is held, and the rotation of the rotating arm 32 can be reliably prevented.

  Returning to FIG. 1, the tool stocker 80a that accommodates a plurality of tools T that can be attached to and detached from the machining spindle 36 corresponding to the first machine tool 10a is provided on the upper and slightly left side (X1 side) of the plate 15b. . In the frame 15, a tool stocker 80b having the same mechanism as the tool stocker 80a is provided on the upper surface of the plate 15b slightly on the right side (X2 side), corresponding to the second machine tool 10b. Hereinafter, the tool stocker 80a will be described as a representative.

  As shown in FIGS. 1 to 3, the tool stocker 80 a is viewed from the front with the rotating shaft 82 extending in the direction of the arrow Z, the magazine motor 83 driving the rotating shaft 82, and the rotating shaft 82 as the center (FIG. 2). And a plurality of holding arms 84 provided radially in a range of about 270 degrees. A substantially C-shaped grip (retainer) 85 that holds the tool T is provided at the tip of each holding arm 84. The grip 85 is an elastic body. When the tool T is pushed into the C-shaped opening, the grip 85 is elastically expanded so that the tool T can be inserted. After the insertion, the grip 85 is closed to hold and hold the tool T. Can do. The held tool T can be pulled out from the C-shaped opening. The number of holding arms 84 is preferably about 16, for example.

  The tool stocker 80a has a portion at about 90 degrees (except for the range of 270 degrees where the holding arm 84 is provided) without the holding arm 84 in a normal state (during machining or non-use) (see FIG. 2). Since the whole is above the plate 15b, the operation of the column 18 and the support 22 is not hindered. On the other hand, when exchanging the tool T of the machining spindle 36, the tool stocker 80a is rotated to direct a predetermined holding arm 84 downward from the end of the plate 15b (see FIG. 5).

  Specifically, an empty holding arm 84 that does not hold the tool T is directed downward, and after adjusting the position of the column 18 in the Z direction, the support 22 is raised. As a result, as shown in FIG. 6, the tool T is held by the holding arm 84, and the unclamp lever 52 is operated in contact with the unclamp block 53 suspended from the upper part of the column 18, whereby the tool T is moved to the tool head. Unclamped to 50. Therefore, the tool T is extracted from the tool head 50 by retracting the column 18 in the direction of the arrow Z2.

  Next, the tool stocker 80a is rotated, the holding arm 84 holding the tool T to be used from now on is directed downward, and the column 18 is advanced in the arrow Z1 direction. As a result, the target tool T is inserted into the tool head 50, and the unclamp lever 52 can be separated from the unclamp block 53 to clamp the tool T by lowering the support 22. Thereafter, the tool stocker 80a is rotated so that all the holding arms 84 are arranged above the plate 15b as shown in FIG.

  Between the tool stocker 80a and the processing spindle 36, there is no intervening mechanism for delivering the tool T on the way as described above, and the holding arm 84 directly grips the tool T. And the attachment / detachment operation of the tool T can be performed directly under the action of the rotating arm 32. Therefore, since a dedicated attaching / detaching mechanism or the like is unnecessary, the structure is simplified, and the time required for attaching / detaching the tool is shortened.

  The tool breakage detection apparatus 200 according to the present embodiment is disposed between the tool stockers 80a and 80b as described above (see FIGS. 1 and 2), and is stored in a pair of the tool stockers 80a and 80b ( The tool breakage is detected almost simultaneously. In this case, the breakage of the tool includes, for example, a state in which a cutting edge or the like of various tools such as a drill is bent or chipped by baking or the like by processing.

  As shown in FIGS. 7 and 8, the tool breakage detection apparatus 200 includes a substantially W-shaped bracket 206 in which a substantially U-shaped tool approaching portion (tool insertion portion) 202 is connected by a moving nut 204, and a bracket 206. It includes a moving mechanism 210 that moves forward and backward along a rail 208 that extends in the Z direction, and a base member 211 that supports the bracket 206 and the moving mechanism 210.

  The tool approaching part 202 constituting the bracket 206 can insert the tool T in the axial direction between a pair of wall members 202a, 202a extending in the arrow Z direction and facing each other, and the inserted tool T is inserted into the wall member 202a, It can be detected by a sensor (detector) 212 provided on the opposite inner wall surface 202a. The sensor 212 is, for example, a non-contact type (photoelectric type) detector that is provided with a light projector and a light receiver on the opposing wall member 202a, and detects the optical axis between the light projector and the light receiver by the tool T blocking. .

  The moving mechanism 210 slides the moving nut 204 on the rail 208 via the ball screw mechanism 216 under the action of the motor 214 fixed on the base member 211, thereby moving the bracket 206 (tool approaching portion 202). It is a mechanism to make.

  As shown in FIGS. 2 and 8, the tool breakage detecting device 200 is between the tool stockers 80 a and 80 b, stored in the tool stockers 80 a and 80 b, and swung via the holding arm 84. It is provided corresponding to the position (breakage detection position) where the tools T are closest to each other and become the distance Da.

  Here, among the tools T used in the machine tool system 10, the tool having the shortest axial length is referred to as a tool TS, and the tool having the longest length is referred to as a tool TL. Accordingly, FIG. 8 is a partially omitted plan view showing a state in which one tool stocker 80a has indexed the shortest tool TS and the other tool stocker 80b has indexed the longest tool TL at the breakage detection position corresponding to the distance Da. It is.

  In this case, as shown in FIG. 8, in the tool breakage detection apparatus 200, the width of the sensor 212 (the distance between the light projector and the light receiver) W1, in other words, the width W1 between the wall members 202a is determined by the tool T (TS, TL) width (diameter, width in plan view) W2 and the axial direction (Z direction) length (depth) L1 of the tool approaching portion 202 is longer than the axial length L2 of the longest tool TL. It is set long. Note that the interval between the pair of wall members 202a and 202a is usually set to be equal to or greater than the width W1 between the sensors 212. Therefore, when the tool approaching part 202 advances and retreats under the action of the moving mechanism 210, the tool T (TL, TS) can be inserted into the U-shaped opening without interference.

  FIG. 9 is a partially omitted front view showing the positional relationship between the tool T stored in the tool stockers 80a and 80b and the tool approaching part 202 (wall member 202a) of the tool breakage detection device 200. FIG. In FIG. 9, for easy understanding, the sensor 212 is omitted, and the interval between the wall members 202a and 202a is shown as a width W1.

  As shown in FIG. 9, the center of rotation of the tool stockers 80a and 80b is referred to as C2, and the distance between the center of rotation C2 and the wall member 202a is referred to as D1, and the farther distance. Is referred to as D2. Of the turning trajectories of the tool T swung by the tool stockers 80a and 80b, the turning trajectory closer to the rotation center C2 is referred to as Tr1, and the far turning trajectory is referred to as Tr2, and these turning trajectories Tr1 and Tr2 The radii around the rotation center C2 are referred to as radii R1 and R2, respectively. In FIG. 9, for ease of understanding, the distances D1 and D2 are illustrated as the radius of the arc from the rotation center C2. However, since the wall member 202a does not operate in the Y direction as described above, Specifically, the distances D1 and D2 are linear distances in the X direction between the wall member 202a and the rotation center C2. In other words, distances D1 and D2 that are distances in the X direction are secured on both ends of the wall member 202a in the height direction (Y direction).

  As understood from FIG. 9, in the tool breakage detection apparatus 200, the turning trajectories Tr1 and Tr2 can pass between the distance D1 and the distance D2 (width W1 portion), that is, the distance D1 has the radii R1 and R2. It is desirable that the distance D2 is smaller (D1 <R1 <R2) and the distance D2 is larger than the radii R1 and R2 (D2> R2> R1). With this configuration, the tool stockers 80a and 80b are not separated from the tool T as shown in FIG. 8 and are close to the tool T as shown in FIGS. 11A and 11B. During rotation, the tool T and the wall member 202a (sensor 212) of the tool approaching section 202 do not interfere with each other, and drive control of each mechanism can be performed more easily.

  As described above, in the tool breakage detection apparatus 200, the two tool approaching portions 202 constituting the bracket 206 are set to have a structure having a length L1 that can correspond to the shortest and longest tools TS and TL, and the tool The structure is set so as not to interfere with the tool T turned by the rotation of the stockers 80a and 80b. That is, the tool breakage detection apparatus 200 has an interference avoidance structure that can avoid interference with all types of tools T stored in the tool stockers 80a and 80b regardless of the advance / retreat position of the bracket 206 by the moving mechanism 210. ing.

  Next, in the machine tool system 10 configured basically as described above, the breakage detection operation of the tool T by the tool breakage detection apparatus 200 will be described with reference to the flowchart of FIG. FIG. 10 is a flowchart showing a breakage detection process of the tool T by the tool breakage detection apparatus 200 according to the present embodiment.

  First, in step S1 of FIG. 10, the tool T is held by the holding arms 84 (grips 85) of the tool stockers 80a and 80b (tool holding step). For example, at the start of use of the machine tool system 10, various tools T used for the workpiece W are held by the holding arms 84 of the two tool stockers 80 a and 80 b by hand. Further, if the workpiece W is being machined, the column 18 and the support 22 are driven as shown in FIG. 6 to hold the used tool T from the machining spindle 36 to the holding arm 84 after use or unnecessary (replacement). ) In other words, step S1 is also a step of storing a large number of desired tools at desired positions in the tool stockers 80a and 80b configured independently of the first machine tool 10a and the second machine tool 10b. (Tool storage process).

  As shown in FIGS. 8 and 9, the tool breakage detection apparatus 200 has the above-described interference avoidance structure with the tool T. Therefore, when the tool T is held and stored by the tool stockers 80a and 80b, the position in the Z direction of the bracket 206 (the tool approaching portion 206) by the moving mechanism 210 does not become a problem. Description will be made assuming that step S1 is executed in a state in which 206 is most advanced to the tool T side (Z2 side) (see FIG. 11A).

  Next, in step S2, under the control of the controller 12, the tool stockers 80a and 80b are rotationally driven, and the tool T for detecting breakage is determined at the breakage detection position (see FIGS. 8 and 9). That is, one tool from each of the tools T stored in the tool stockers 80a and 80b is detected, and the two tools T are indexed to a position where the distance Da is closest to each other. Thereby, it will be in the state where the tool T of the detection object was inserted inside each of a pair of tool approach part 202 of the state advanced in the Z2 direction (refer FIG. 11A).

  In this case, the tool stockers 80a and 80b can easily and quickly determine a desired tool T under the control of the controller 12 based on an identification address (not shown) written on the tool T. In other words, the controller 12 stores the length in the axial direction of the tool T indexed at the breakage detection position in a normal state (a state without breakage).

  In step S3, the tool breakage detection device 200 is driven to check the breakage state of the tool T that has been determined at the breakage detection position. That is, the moving mechanism 210 is driven from the state shown in FIG. 11A, and the pair of tool approaching portions 202 are retracted in the Z1 direction as shown in FIG. 11B. In FIG. 11A and FIG. 11B, the broken blade edge portion is shown by a broken line, assuming that the blade edge of the tool TS held in one tool stocker 80a is broken.

  In this case, as can be understood from FIGS. 11A and 11B, the sensor 212 moves from a position where the tool approaching portion 202 is closest to the tool T side (see FIG. 11A) to a position where it is most separated (see FIG. 11B). When this is done, the tip of the shortest tool TS (cutting edge) and the tip of the longest tool TL (cutting edge) can be detected and fixed to the wall member 202a. Accordingly, in step S3, the tool approaching unit is moved along the indexed tool T and away from the tool T under the action of the moving mechanism 210 with the rotation of the tool stockers 80a and 80b stopped. By retracting 202, breakage of all lengths of the tool T from the shortest to the longest held by the two tool stockers 80a and 80b by the sensor 212 can be easily detected. Of course, the bracket 206 may be set at the retracted position (see FIG. 8) at the start of detection, and the detection may be performed by advancing from there.

  That is, in step S3, when the bracket 206 is moved, the tool approaching portion 202 (sensor 212) when the origin is the position most advanced to the tool T side or the most retracted position from the tool T side by a linear sensor or the like (not shown). ). Needless to say, the base end position in the Z direction of the tool T indexed to the breakage detection position is always constant.

  Then, based on the obtained movement amount and the information on the axial length of the tool T in the normal state determined to the breakage detection position, the tip (blade edge) position of the tool T actually detected is normal (breakage). It is determined whether or not it is within the position range (step S4). For example, in the case of the shortest tool TS, it can be determined that there is no breakage if the cutting edge is detected with the sensor 212 arranged as shown in FIG. 11A, but the cutting edge is broken as shown by the broken line in FIG. 11A. If it is, the sensor 212 cannot detect the cutting edge of the tool TL and determines that there is breakage.

  As a result of the determination in step S4, if it is determined that there is no breakage, the tool T is normal. Therefore, it is preferable to return to step S1 or step S2 to detect breakage of the next tool T or the like. On the other hand, if it is determined that there is a breakage, an alarm is generated using a speaker, a lamp, etc. (not shown) in step S5. Thereby, it is possible to promptly notify the operator that the breakage has occurred, and to appropriately perform replacement, maintenance, etc. of the broken tool T. At this time, the system may be stopped if necessary, but the system is not stopped if the broken tool T is not used for the workpiece W currently being machined (there is no plan to use it). While the machining is continued, the controller 12 can perform control so that the tool T is not mounted on the machining spindle 36 side until the broken tool T is replaced. If another tool T is subsequently detected, the process may return to step S1 or step S2.

  The step S1 is not necessarily performed. For example, when the same tool T held in the tool stockers 80a and 80b is used every day, before the work by the daily machine tool system 10 is started. When performing the breakage detection operation as an inspection operation, the tools T that have already been stored may be detected sequentially.

  As described above, according to the tool breakage detection apparatus 200 according to the present embodiment, the bracket that includes the pair of tool approaching portions 202 that can simultaneously support the two tool stockers 80a and 80b, and supports the tool approaching portion 202. The breakage of the tool T is detected by causing the moving mechanism 210 to advance and retreat 206 in the axial direction (Z direction) of the tool T. That is, the tool breakage detection device 200 detects breakage of the tool T on the tool stocker 80a, 80b side that stores the tool T, not on the machine unit side that works the workpiece W such as the first machine tool 10a.

  Therefore, for example, with respect to the tool T that is mounted on the machining spindle 36 and used for machining the workpiece W, and then temporarily returned to the tool stockers 80a and 80b, machining with another tool T is performed. In the middle, the breakage can be confirmed. For this reason, if a breakage is found in the tool T, it can be quickly replaced on the tool stocker 80a, 80b. If necessary, it is possible to perform control so that the machining spindle 36 is not mounted.

  Thereby, every time the tool T is mounted on the machining spindle 36 and used for machining, the broken state of the tool T can be confirmed, and the broken tool T is effectively avoided from being used for machining. Can do. In addition, it is possible to continue machining the workpiece on the machine unit side while detecting breakage on the tool stocker side, so there is almost no need to stop the system, reducing cycle time and improving production efficiency. Is also possible.

  Moreover, the tool breakage detection apparatus 200 is arrange | positioned corresponding to the tool stockers 80a and 80b outside the processing area by the said machine unit. For this reason, it is possible to avoid erroneous detection of the sensor 212 due to cutting waste or cutting oil due to processing of the workpiece W. At the same time, since the moving mechanism 210 is not affected by the cutting waste or the like, the movement amount of the bracket 206 can be controlled more accurately, and the breakage of the tool T can be detected with higher accuracy.

  Further, the tool breakage detection apparatus 200 employs the interference avoidance structure that can simultaneously cope with the shortest and longest tools TS and TL among the tools used in the system (see FIGS. 8 and 9). For this reason, since both types of tool stockers 80a and 80b can detect breakage of different types of tools substantially simultaneously, the versatility is high, and while the breakage is detected by one tool stocker 80a, the other tool stocker 80b performs machining. Automatic tool exchange with the main shaft 36 can also be performed, and it is possible to further improve production efficiency by avoiding as much as possible tool breakage and system stoppage due to the detection.

  The tool breakage detection device 200 corresponds to a position (breakage detection position) that is stored in both tool stockers 80a and 80b and that is the closest distance Da between the tools T that are swung via the holding arm 84. (See FIGS. 8 and 9). For this reason, the bracket 206 holding the tool approaching portion 202 can be miniaturized as much as possible, so that the moving mechanism 210 can also be configured with a low output and a small size. Therefore, the tool breakage detection apparatus 200 can be reduced in size and weight, and the degree of installation freedom can be increased.

  As described above, the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

  For example, the tool approach part which comprises a tool breakage detection apparatus may be other than U-shape. As an example thereof, as shown in FIG. 12, a tool breakage detection device 200 a having a bracket 207 in which a flat tool approaching portion 203 formed of a single wall member 202 a is connected by a moving nut 204 can be configured. In this case, a sensor (detector) 218 capable of detecting the tool T with one device, for example, a non-contact type proximity sensor is used. In such a tool breakage detection device 200a, the entire device can be further reduced in size and weight, and the tool approaching portion 203 is a single plate, so that the interference avoidance structure as shown in FIG. However, there are few design elements and it can be constructed very easily.

  Furthermore, as shown in FIG. 13, as a detector for detecting breakage of the tool T, a tool breakage detection device 200b including a contact sensor 220 may be configured. The sensor 220 is, for example, a proximity switch that detects the tool T when the elastic contact piece 220a is brought into contact with the tool T and tilted.

  In addition, although the case where the number of tool stockers is two was illustrated in the said embodiment, of course, it can also comprise in three or more. For example, as shown in FIG. 14, when a tool stocker 80c is installed in an upside-down direction above the tool stockers 80a and 80b, the tool breakage detection device 200c corresponding to the tool stocker 80c is replaced with the tool breakage detection device 200. What is necessary is just to provide integrally or separately. Furthermore, as shown in FIG. 15, when three tool stockers 80 a to 80 c are arranged side by side, for example, together with two tool breakage detection devices 200 that are integrated or separated, 2 are further integrated or separated. What is necessary is just to provide the tool breakage detection apparatus 200c of a stand. When three or more tool stockers are provided in this way, at least two tool stockers correspond to the breakage detection positions (see FIGS. 8 and 9) that are closest to each other between the tools T. Any or all of the tool breakage detection devices may be installed.

  In the above embodiment, the U-shaped or flat tool approaching portion is exemplified, but the tool approaching portion may be a rod shape or the like, and in short, a sensor for detecting breakage of the tool T can be appropriately arranged. I just need it. Therefore, for example, the tool approaching portion can be formed in a cylindrical shape. In this case, however, it is needless to say that the tool T needs to be removed from the inside of the tool approaching portion when the tool stocker rotates. Further, the tool approaching unit may be configured to be able to simultaneously support not only one but two or more tools stored in one tool stocker. In this case, for example, three or more brackets A tool approaching portion may be provided.

  Further, the moving mechanism constituting the tool breakage detecting device is not limited as long as it can appropriately move the bracket including the tool approaching portion forward and backward, and in addition to the above ball screw mechanism, linear drive, swing link drive, rack and pinion It may be a drive or the like.

  Of course, one machine tool may constitute the machine unit. In this case, for example, two tool stockers corresponding to the one machine tool may be provided.

1 is a partially cutaway perspective view of a machine tool system equipped with a tool breakage detection device according to an embodiment of the present invention. It is a front view of the machine tool system shown in FIG. It is a side view of the machine tool system shown in FIG. It is a cross-sectional side view of the support body and the process spindle which comprise the machine tool system shown in FIG. In the machine tool system shown in FIG. 1, it is a partial cross section perspective view which shows the state which changes a tool with a tool stocker. FIG. 6 is an enlarged side view of a column, a tool stocker, and a peripheral portion thereof when the tool change shown in FIG. 5 is performed. It is a perspective view of the tool breakage detection apparatus shown in FIG. It is a partially omitted plan view showing a tool breakage detection device and a tool stocker that has indexed a tool at a breakage detection position. It is a partially-omission front view which shows the arrangement | positioning relationship between the tool stored in the tool stocker, and a tool approach part. It is a flowchart which shows the tool breakage detection process by the tool breakage detection apparatus which concerns on this embodiment. FIG. 11A is a partially omitted plan view showing a state where the tool approaching portion of the tool breakage detection device is moved to the tool side, and FIG. 11B is a state where the tool approaching portion of the tool breakage detection device is separated from the tool side. FIG. It is a perspective view of the tool breakage detection apparatus which concerns on the 1st modification of this embodiment. FIG. 10 is a partially omitted plan view showing a tool breakage detection device and a tool stocker that has determined a tool at a breakage detection position according to a second modification of the present embodiment. It is a front view which shows typically the structure provided with the tool breakage detection apparatus which concerns on the 3rd modification of this embodiment. It is a front view which shows typically the structure provided with the tool breakage detection apparatus which concerns on the 4th modification of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Machine tool system 12 ... Controller 36 ... Processing spindle 80a-80c ... Tool stocker 200, 200a-200c ... Tool breakage detection apparatus 202, 203 ... Tool approach part 206, 207 ... Bracket 210 ... Moving mechanism 211 ... Base member 212, 218, 220 ... Sensor

Claims (5)

A machine tool system comprising a machine unit that mounts a detachable tool and processes a workpiece, and a plurality of tool stockers that store a plurality of the tools so as to be exchangeable with the machine unit and that calculate the tools by a rotating operation. The tool breakage detection device of
The tool breakage detection device includes a bracket provided with a plurality of tool access portions that can simultaneously access at least one of the tools stored in each tool stocker,
A plurality of non-contact type or contact type detectors that are provided in each tool approaching part and detect breakage of the tool;
A moving mechanism for moving the bracket in the axial direction of the tool;
A tool breakage detecting device characterized by comprising: In the tool breakage detection apparatus according to claim 1,
The tool approach portion does not interfere with a tool having the shortest and longest axial length among the tools stored in the tool stocker in a state where the tool is in a position closest to the tool by the moving mechanism. A tool breakage detecting device having a structure. In the tool breakage detecting device according to claim 2,
The detector has a shortest and longest axial length among the tools stored in the tool stocker when the tool approaching portion is moved from a position closest to the tool to a position farthest away from the tool. A tool breakage detecting device, which is fixed at a position where breakage of a tool having a can be detected. In the tool breakage detection device according to any one of claims 1 to 3,
The tool approaching portion has a structure that does not interfere with a tool stored in the tool stocker when the tool stocker is rotated in a state where the tool is close to the tool by the moving mechanism. Tool breakage detection device. In the tool breakage detection apparatus according to any one of claims 1 to 4,
The tool approaching unit may check a broken state when the tools stored in at least two tool stockers among the plurality of tool stockers are indexed to the closest positions by the rotation operation. A tool breakage detecting device, which is installed at a possible position.

Images