JPH0471662B2 - - Google Patents

Description

Detailed Description of the Invention (Objective of the Invention) The present invention eliminates not only conventional errors caused by wear and thermal displacement of the cutter itself, but also errors caused by thermal displacement of the ball screw of the headstock and tool rest and thermal displacement of the machine body. The present invention also relates to a cutting edge position detection device for a machine tool that can automatically correct the position.

(Prior art) As shown in Japanese Unexamined Patent Application Publication No. 53-59982, automatic correction of the tool position in a conventional numerically controlled lathe is achieved by installing a swingable arm on the tail stock of the lathe, and adjusting the X-axis and Z-axis at the tip of the arm. There are examples in which detectors are stacked vertically to detect the cutting edge in different directions, and a single block is used to detect when the cutting edge touches the surface of the block, as shown in Japanese Patent Publication No. 50-12630. In the former case, the detectors are stacked vertically, so the X
Not only is it difficult to position the axis and Z-axis detectors simultaneously on the X-Z plane, that is, the plane where the headstock and tool rest move for machining, but they are also set in the spindle axis direction, so that the cutting edge is not aligned with the spindle. It has been impossible to measure the position of the cutting edge of a oriented internal tool because the tail stock interferes with the tool and the turret. In addition, in the latter case, since the detection head consists of a single block, there is an extremely high risk that the cutting edge will collide with the block during measurement and damage the cutting edge. As the size of the detection head increases, there are many problems such as the need for a strong support device to position the detection head at an accurate cutting edge measurement position. Furthermore, since multiple measurement surfaces are formed on a single detection block, the size of the measurement surface inevitably increases in proportion to the size of the block itself, resulting in variations in measurement positions and measurement errors. There is a high risk of errors. In addition, in order to eliminate such problems and perform accurate measurements on each measurement surface, it is necessary to maintain the parallelism and perpendicularity of each measurement surface extremely accurately, which requires a lot of time and effort to process the blocks. Furthermore, with such a single block configuration, there arises the disadvantage that mounting errors of the block, positional deviations over time, and deformation of the block itself simultaneously affect all measurement surfaces.

In addition, in both cases, the position of the detector during measurement is far from the front part of the chuck where the work is actually machined, such as the side of the spindle or the front of the headstock, so the position of the cutting edge is The measured position and the position where the measured tool is used for machining are far apart, and the positioning error of the drive system of the tool post regarding the distance between the measured position and the machining position (ball screw pitch error, etc.) This has the disadvantage that errors such as guide surface errors remain uncorrected and appear as machining errors during machining. In particular, when performing high-precision machining such as finish machining of a workpiece using a raw jaw, in order to perform accurate machining, it is important to measure the position of the cutting edge of the tool used for machining as much as possible to ensure the accuracy of the workpiece to be machined and the chuck to which the raw jaw is attached. Preferably in the front.

On the other hand, in order to correct changes in the position of the cutting edge due to thermal displacement between the headstock and the tool post, it is desirable to install a cutting edge position detection device on the headstock, but in order to also satisfy the high precision machining described above, This posed an extremely difficult problem, as it was necessary to position the detection device in the space in front of the chuck by some method on the headstock in a manner that would prevent interference with the chuck and would not interfere with normal machining. Therefore, all conventional headstocks equipped with cutting edge position detection devices are installed on the side of the chuck, and in that case, as a natural result, the distance between the measurement position and the machining position cannot be measured. The positioning error of the drive system of the tool post (ball screw pitch error and guide surface error) is
It was treated as something that could not be corrected.

Moreover, conventional detectors are only capable of measuring the position of the cutting edge in the X-axis and Z-axis directions. No consideration was given to what should be done. For example, when cutting an end face with an external cutting tool, the important thing is the position of the external cutting tool in the direction of the spindle axis.
The position is not perpendicular to the spindle axis direction, which is important in normal outer diameter machining of workpieces. In this way, even with the same tool, the required cutting edge position is completely different depending on the machining process being performed, so simply arranging the detection heads will not allow the operator to immediately determine which detection head should be used to measure the cutting edge position. This makes it difficult to measure the position of the cutting edge, and requires a high degree of skill.

Furthermore, conventional detectors have no means to protect against cutting dust such as cutting water and swarf when not measuring, and therefore during machining of a workpiece, and contamination from cutting dust may impede proper measurement performance over a long period of time. The problem has arisen that it is difficult to maintain the system for a long time.

According to the present invention, each of the detection heads facing the first and second directions can be simultaneously positioned on the plane in which the headstock and the tool rest move for machining, and the detection head can be miniaturized. A first object of the present invention is to provide a cutting edge position detection device that does not damage the tool cutting edge during measurement.

Furthermore, it is an object of the present invention to provide a highly reliable cutting edge position detection device in which the detection head is easy to manufacture and mount, and mounting errors and changes over time of one detection head do not affect the measurement accuracy of other heads. The second purpose is to

In addition, it is possible to position the detection device in front of the workpiece holding means by mounting the detection device on the headstock.Moreover, the detection head can be adapted to the machining mode of the workpiece by the tool to be measured, so that it can be used when measuring the cutting edge. , the operator can measure the necessary cutting edge position simply by touching the corresponding detection head according to the processing mode, and the cutting edge can prevent contamination by cutting dust when not measuring. A third purpose is to provide a position detection device.

(Structure of the Invention) A first aspect of the present invention is that a bending arm having a bent arm shape as a whole is swingably mounted on the headstock, and a measuring device main body is attached to the tip of the bending arm. The swinging motion of the arm causes the workpiece holding means to move between a retracted position in which the headstock and the turret are retracted from the movement plane for machining, and a position in which the headstock and the turret are evacuated from the movement plane for machining and within the movement plane for machining. A detection head for end face processing is provided in the first direction on the outside of the measuring device main body, and a detection head for end face processing is provided in the first direction, and
A detection head for outer diameter machining and a detection head for inner diameter machining are arranged facing backward in the direction of , the detection head for outer diameter machining is arranged on the side closer to the tool rest, and the detection head for inner diameter machining is arranged on the opposite side. The detection heads are provided in such a manner that the directions in which the measurement surfaces of the detection heads face do not intersect with each other, and the measurement surfaces are movable, and a signal transmission path is provided between each detection head and an automatic control device provided in the machine tool. Connected and configured via.

In a second aspect of the present invention, a bending arm having a bent arm shape as a whole is swingably mounted on the headstock, and a measuring device main body is attached to the tip of the bending arm by the swinging movement of the bending arm. , a retraction position where the headstock and the turret are evacuated from the movement plane for machining, and a measurement provided within the movement plane for the machining of the headstock and the turret and in front of the workpiece holding means. Provided so that it can be moved freely between positions,
A detection head for end face machining is provided on the outside of the measuring device main body in the first direction, and a detection head for external machining and a detection head for internal diameter machining are provided facing away from the second direction. The detection head for internal diameter machining is arranged on the side close to the tool rest and the detection head for inner diameter machining is arranged on the opposite side, and the directions in which the measurement surfaces of the detection heads face do not intersect with each other, and are provided so as to be freely pushable, and a cover means is provided at the retracted position to protect the detection head of the measuring device main body from cutting dust generated during the cutting operation of the workpiece held by the workpiece holding means, and the It is constructed by connecting each detection head to an automatic control device provided in the machine tool via a signal transmission path.

To explain the present invention with reference to figures of embodiments, the first
In the figures to FIG. 6, a bracket 3 is attached above the axis X-X of the main spindle 2 on the front edge of the upper surface of the headstock 1 of a numerically controlled lathe L, and a rotation axis 4 perpendicular to the main spindle 2 is attached to this bracket 3. Detection of the shape of an arm that is rotatably supported up and down by an angular bearing 5 and a cylindrical roller bearing 6, a hydraulically driven swing motor 7 is attached to one end of the rotation shaft 4, and a bent arm shape at the other end. Fix the base of arm 8,
The axis X is located within the vertical rotation plane of this detection arm 8.
- The detection head 10 of the outer diameter cutting tool B ₁ is located on the relative movement axis (first
They are installed facing each other in the direction (indicated as Z-Z in the figure). The detection head 10 has its measurement surface 10' facing in the horizontal right direction in FIG. It is set up in the shape of In addition, the detection head 11 of the end face cutting tool B ₂ is located on the front surface of the outer periphery of the main body 9 (on the right side in Fig. 2) in the direction of the spindle axis (indicated as X-X in Fig. 2).
It is installed opposite to. Detection head 1
1 is provided in such a manner that its surface 11', which is a measurement surface, faces in the horizontal right direction in FIG. 2, that is, in the positive direction of the main shaft axis. Also, the main body 9
A detection head 12 of an internal cutting tool B ₃ is mounted on the front side of the outer circumference (left side in FIG. 1) so as to face the relative movement axis direction of the tool post T.
The detection head 12 has its measurement surface 12' facing in the horizontal left direction in FIG.
The relative movement axis (indicated as Z-Z in FIG. 1) is oriented in the negative direction. Further, the detection heads 10 and 12 are provided opposite to each other. In addition, each detection head 10, 11,
12, as described above, the measurement surfaces of each head do not intersect with each other, and when measuring the cutting edge, the headstock and the tool rest are within the movement plane for machining, that is, in the case of this embodiment, Provided so as to be located on a plane formed by the X-X axis and the Z-Z axis,
A cam 13 is cut approximately in the center of the rotating shaft 4, and limit switches 14 and 15 are provided in contact with the cam 13 to command rotation and stop of the swing motor 7 that rotates the detection arm 8. An upper limit stopper 17 is provided in the cavity 16 of the bracket 13, and is mounted on the headstock 1 to restrict the upper limit of the rise of the detection arm 8, so that the back surface of the detection arm 8 comes into contact with the upper limit stopper 17, and when the detection arm 8 is lowered, A lower limit stopper 18 that regulates the accurate detection position of the detection device main body 9 at the tip is attached to the front surface of the headstock 1, and an adjustment screw is attached to the tip of the lower limit stopper 18 and comes into contact with an abutment piece 19 attached to the detection arm 8. 20 is provided. The detection arm 8 has air nozzles 21, 22, 2 for removing chips toward each of the detection heads 10, 11, 12.
3 are installed, and these nozzles 21, 22,
23 is connected to a compressed air source (not shown) via an air hose 25 via a collection box 24. In the figure, C represents a chuck, N represents a claw of the chuck C, and T represents a turret. This tool post T is moved in the X-axis direction and the Z-axis direction by a ball screw or the like, and its position is detected by a known position detector such as an encoder.

In FIGS. 7 and 8, when the detection arm 8 is not detected, the upper limit stopper 17 rotates upward.
A bulkhead 2 attached to the front of the headstock 1 protects the detection device main body 9 and the detection arm 8 from cutting debris such as chips and cutting water when the detection device body 9 and the detection arm 8 are held by the headstock 1.
Through holes 28, 29 of the detection arm 8 provided at 6, 27
A door 30 for opening and closing is slidably provided between the partition walls 26 and 27. More specifically, the door 30 is mounted below a sliding frame 34 that is slidably fitted onto a rail 33 horizontally mounted above the through hole 28 inside the outer partition wall 27 by means of brackets 31 and 32. A door plate 35 is attached with a hanging width slightly wider than the through holes 28 and 29, and is connected to the tip of a rod 38 of a hydraulic or pneumatic cylinder 37 whose base is pivoted to a bearing 36 attached to the inside of the partition wall 26. The sliding frame 34 is connected to the sliding frame 34 by a connecting plate 39, and the opening and closing of the door 30 by the cylinder 37 is linked to the vertical movement of the detection arm.

The above-mentioned detection device main body 9 will be described in more detail as follows.
9 to 12, the base 42 of the housing 41 is attached to the main body mounting portion 40 at the tip of the detection arm 8.
are screwed together with mounting bolts 43, 43, so that the axis A-A of the detection device main body 9 is aligned with the axis of the detection arm 8, and the axis A-A is installed inside this housing 41.
A sliding hole 44 is perpendicular to the sliding hole 44, and a T-shaped sliding hole 45 is bored in the axial direction at right angles to the sliding hole 44, and the detection shaft 46 is slid in the sliding hole 44 in the Z-axis direction. A groove 47 is provided in the middle of this detection shaft 46 and is freely fitted into the groove 47.
A stopper 4 is screwed onto the outside of the housing 41.
The projection 49 of No. 8 is fitted to prevent the detection shaft 46 from rotating so that it slides only in the Z-axis direction, and a V-shaped groove 50 is provided in the center of the detection shaft 46 on the sliding hole 45 side. The detection heads 10 and 12 are adjustably screwed on both ends, and a stainless steel ball 51 has an outer diameter that can slide into the sliding hole 45 in the direction of the axis A-A.
is inserted into this sliding hole 45 and brought into contact with the V-axis groove 50 of the detection shaft 46, and further, a slide shaft 52 is slidably inserted into this sliding hole 45, and a pin 53 is inserted into this sliding shaft 52. is attached in a perpendicular direction and protrudes from both long holes 55, 55 provided in the cylindrical part 54 of the housing 41, and a bush 56 fitted in the cylindrical part 54 is passed through, so that the proximal end surface 57 of the slide shaft 52 The limit switch is mounted by making it contact with the stainless steel ball 51, screwing the rod 58 onto the tip of the slide shaft 52 (the left end in FIG. 11), and making it come into contact with the stepped end surface 59 inside the cylindrical portion 54 of the housing 41. The stand 60 is fitted into the limit switch storage chamber 61 of the cylindrical portion 54, the cover 63 is screwed in with the coil spring 62 interposed therebetween, the limit switch mounting base 60 is elastically pressed, and the limit switch mounting base 60 is screwed onto the limit switch mounting base 60. A booth d is provided between the detection terminal 65 of the high-sensitivity detection limit switch 64 and the front end surface 66 of the rod 58, and the cable 67 of the limit switch 64 is connected to a numerical control box (not shown). A coil spring 70 is interposed between the bush 56 and a ring 69 fixed with a stop ring 68 in the middle thereof, and inspection slots 71 are provided on both sides of the cylindrical portion 54 near the detection terminal 65 for inspecting the booth d. , 71 are drilled.

On the other hand, a bracket 72 is screwed to the upper front end of the base 42 of the housing 41 with bolts 73, and an insertion hole 74 is bored through the bracket 72 horizontally in a direction perpendicular to the axis A-A. Needle bearings 76, 76 are fitted on both sides of the bracket 72 of the shaft 75 inserted into the insertion hole 74, and the needle bearings 76, 76 are fitted into another bracket 77.
A detection head 1 is inserted into the fulcrum of the bracket 77 so as to be rotatable, and detects the end face cutting tool _B2 at the center of a bridge member 78 installed on the upper rear edge of the bracket 77.
1 by screwing the hanging parts 7 on both sides of the bracket 77.
9, 79 are brought into contact with the pin 53, an adjusting screw 80 is screwed into the lower part of one of the hanging parts 79, and the tip 81 of the adjusting screw 80 is inserted into the base part 42 of the housing 41. It is brought into contact with the front surface 82. In the figure, 83 indicates a cover provided on the main body mounting portion 40 of the detection arm 8.

Further, in this embodiment, a mechanism is shown in which the detection device body 9 is swung down from above the spindle 2, but as long as the rotation shaft 4 is fixed on the headstock 1, the detection arm can be moved from the side of the spindle center XX, etc. A similar effect can be obtained by rotating 8.

(Function of the Invention) To explain the function of the present invention with reference to the drawings of the embodiment, in FIGS. 1 and 2, when the processed workpiece (not shown) is removed from the chuck C,
The front of chuck C will be a blank space. Next, the tool position needs to be corrected (in this case, the outside diameter cutting tool B ₁ is the target of correction), that is, when the tool B ₁ is indexed by the tool rest (turret) T and directed toward the cutting position. , in FIG. 7, the cylinder 37 provided inside the partition wall 26 operates to move the rod 38 in the direction of arrow P.
When pushed in the direction, the connecting plate 39 is attached to the tip of the rod 38.
The sliding frame 34 of the door 30 attached through the rail 33 moves in the direction of arrow P together with the door plate 35 hanging down on the rail 33, and the through holes 28 and 28 provided in the partition walls 26 and 27
29 will be held. Next, the swing motor 7 attached to the bracket 3 provided on the front upper edge of the headstock 1 is activated.
When the rotation shaft 4 connected to this is rotated in the direction of arrow R, the detection arm 8, which has its base end fixed to the rotation shaft 4 and has the detection device main body 9 attached to its tip, also rotates.
Detection head 10, 1 attached to detection device main body 9
1 and 12 pass through the through holes 28 and 29 from the retracted position on the left side of the partition walls 26 and 27 in FIG. Contact piece 19 provided in the middle of 8
is in contact with the adjustment screw 20 at the tip of the lower limit stopper 18 provided on the headstock 1, and the detection device main body 9 at the tip of the detection arm 8 is positioned in front of the spindle 2, that is, on the right side of FIG.
The moving plane for machining the headstock and tool rest where normal cutting is performed and cutting dust such as cutting water and chips is applied (direction perpendicular to the paper plane passing through the X-X axis in Figure 2) The detection head 10,1 is placed at the measurement position within
1 and 12 are positioned (see Figures 2, 5, and 6). At this time, the detection arm 8
is formed in a bent shape, so even if the detection arm 8 is rotated in the direction of arrow R, there will be no interference between the chuck and the arm, and the detection device main body 9 can be accurately positioned in front of the chuck. be done. Simultaneously with the rotation of the arm 8, the intermediate cam 13 of the rotation shaft 4 rotates in the direction of arrow R in FIGS. When it comes into contact with , the swing motor 7 stops.

At this time, the adjustment screw 20 of the lower limit stopper 18
is adjusted appropriately so that the detection device main body 9 is placed at an accurate measurement position, that is, each detection head 10, 11, 12 is located on the movement plane for machining the tool rest and the headstock, but the lower limit Even if the adjustment of the stopper 18 is not proper, each detection head 10,1
1, 12, surfaces 10', 11', as measurement surfaces;
The amount of deviation from the direction of the extension line in which the detection arm 8 is directed is not directly affected by the amount of deviation of the rotation angle of the detection arm 8 in the direction of the arrow R. That is, the rotation direction of the detection heads 10, 11, 12 by the detection arm 8 with respect to the movement plane is perpendicular to the movement plane, and
Surfaces 10', 11', 1 as measuring surfaces of 1, 12
Since the extension line direction of 2' is set parallel to the movement plane for machining the headstock and tool post, even if the detection arm 8 is slightly displaced in the vertical direction in Fig. 2 with respect to the relative movement plane. Also, there is no effect in the Z-axis direction in the figure, which is the direction in which surfaces 10' and 12' as measurement surfaces face, and there is an effect only in the X-axis direction in the figure, which is the direction in which surface 11' faces. . Therefore, the radial dimension of the workpiece (Z-Z axis direction in the figure), which is particularly important for lathe machining, can be positioned with extremely high precision. Also, regarding the amount of positional deviation in the direction of the spindle axis, the detection head 1
1 is shifted downward in FIG. 2 and in the X-axis direction, so that the influence of the positional shift of the detection arm 8 in the direction of arrow R can be greatly alleviated. Note that, as shown in this embodiment, the rotation angle of the detection arm 8 with respect to the movement plane for machining the spindle stock and the tool rest is at right angles when each measurement surface 1
It is most desirable to be able to eliminate the influence of the positional deviation of arm 8 in the direction of arrow R with respect to 0', 12', but considering that the amount of positional deviation of arm 8 in the direction of arrow R itself is small, each measurement Since the influence of the positional deviation of the surfaces 10', 11', and 12' as surfaces with respect to the X-axis and Z-axis is smaller than the amount of positional deviation of the arm in the direction of arrow R, the rotation of the arm 8 with respect to the plane of movement is smaller. The moving angle can also be in a direction intersecting the moving plane.

Next, as shown in FIG. 2, compressed air is blown out from air nozzles 21, 22, 23 for removing chips attached to the detection arm 8, and the cutting edge is brought into contact with the detection heads 10, 11, 23.
Remove chips etc. that adhere to the cutting edge when it comes into contact with the cutting edge 12 to clean the cutting edge. In Fig. 1, the tool post T rapidly moves in the direction of arrow Q, and after the external diameter cutting tool B ₁ attached to the tool post T rapidly approaches the detection device main body 9, it moves to a position previously input to the NC device. Then, the cutting edge B1 _' of the cutting tool _B1 gently comes into contact with the surface 10' of the detection head 10 for outer diameter cutting (see FIG. 12). At this time, since the outer diameter cutting detection head 10 is provided for measuring the cutting edge during outer diameter machining, the operator has no hesitation as to which detection head should be used to measure the outer diameter cutting tool _B1 . The measuring operation can be performed by selecting the detection head 10 for outer diameter cutting provided in accordance with the processing content without any trouble.

To explain the detection operation in detail, in FIG. 11, when the cutting edge B ₁ ′ of the outer diameter cutting tool B ₁ comes into contact with the surface 10 ′ of the detection head 10 and pushes the detection shaft 46 in the direction of arrow Z, the detection shaft 46 The slope 5 of the V-shaped groove 50 provided in
0' pushes the stainless steel ball 51 in the direction of arrow X,
This stainless steel ball 51 moves inside the sliding hole 45 with the arrow
When the slide shaft 52, whose proximal end surface 57 is brought into contact with the elastic force of the coil spring 70, is slid in the direction of the arrow X against the elastic force of the coil spring 70, as shown in FIG. This slide shaft 5
The rod 58 screwed onto the tip of the rod 58 also moves in the direction of the arrow The movement of the cutting tool B ₁ stops at the moment when the tool B 1 comes into contact with the detection terminal 65 and the high-sensitivity detection limit switch 64 is activated, and the difference between the coordinate values at that time and the coordinate values of the previously commanded measurement position is calculated by The control device automatically measures and calculates the position of the cutting edge of bite _B1 .
If the tool B ₁ does not stop even if the high-sensitivity detection limit switch 64 is activated by mistake (manual operation, etc.), protect the high-sensitivity detection limit switch 64 by pressing the high-sensitivity detection limit switch 64 against the coil spring 62. do.

When the blade edge position is detected and the numerical values in the NC control device are automatically corrected, the cleaning air nozzle 21,
The air blowing from 22 and 23 stops, and the rotation shaft 4 of the swing motor 7 attached to the bracket 3 provided on the headstock 1 rotates in the direction of arrow R', which is the opposite direction from the previous one. The detection arm 8, whose base is fixed, also rotates in the direction of arrow R' from the relative movement plane until then, when it comes into contact with the upper limit stopper 17 through the through holes 28 and 29 provided in the partition walls 26 and 27. The cam 13 formed on the shaft 4 touches the limit switches 14 and 15 for detecting the rotational position, and the swing motor 7 is stopped. When the detection arm 8 stops at the upper limit stopper 17, the cylinder 37 provided on the partition wall 26 operates in the direction of arrow P' to pull back the door plate 35 of the door 30 in the direction of arrow P' and close the through holes 28 and 29. Therefore, the detection heads 10, 11, 12 are positioned at the retracted position, and the detection heads 10, 11, 12 of the detection device main body 9 can be protected from cutting dust such as chips and cutting water during the cutting operation.

Since the base of the detection arm 8 is pivoted on the spindle 2 of the headstock ₁ , the amount of correction of the position of the cutting edge B ₁ ′ of the cutting tool B 1 depends only on the wear of the cutting edge B ₁ ′ of the cutting tool B ₁ . It also includes correction of errors caused by expansion and contraction due to thermal displacement of the ball screw of the numerically controlled lathe L and the lathe structure (both not shown). In addition, since the measurement of the cutting edge position is performed in front of the chuck, machining using the measured tool will be performed near the position where the cutting edge of the tool was measured, and the actual cutting edge measurement position will be different from the actual cutting edge position. It is now possible to set the machining positions extremely close to each other, and it is possible to prevent a decrease in machining accuracy due to errors in the drive system such as the tool rest as much as possible between the measurement position of the cutting edge and the actual machining position. High precision processing becomes possible.

Next, the detection function of the internal cutting tool _B3 will be explained.

The cutting edge detection operation is performed by bringing the cutting edge B ₃ ′ of the cutting tool B ₃ into contact with the surface 12 ′ of the detection head 12 for internal cutting.
The detection shaft 46 moves in the direction of the arrow Z', the slope 50'' of the V-shaped groove 50 slides the stainless steel ball 51 in the direction of the arrow X, and the other actions are performed by the outer diameter cutting tool _B1.
The same is true for . At this time, since the detection head 12 for inner diameter cutting is provided for measuring the cutting edge during inner diameter machining, the operator does not have any hesitation as to which detection head should be used to measure the inner diameter cutting tool _B3 . The measuring operation can be performed by selecting the detection head 12 for inner diameter cutting provided in accordance with the processing content.

Next, the detection action of the end face cutting tool _B2 will be explained. The detection operation is performed as follows. First, in FIG. 12, the cutting edge B ₂ ′ of the cutting tool B ₂ hits the surface 11 ′ of the detection head 11 for end face cutting attached to the center of the bridge member 78 of the bracket 77 provided on the upper part of the housing 41 via the bracket 72 . When the shaft 75 is inserted into the bracket 72 attached to the upper part of the base 42 of the housing 41 at right angles to the axis A-A as shown in FIGS. rotates in the direction of arrow S about the shaft 75, and the front surfaces 79', 7 of the hanging parts 79, 79
9' pushes the pin 53 inserted into the bush 56 elastically loaded by the coil spring 70 in the direction of the arrow X, so the slide shaft 52 with the pin 53 inserted is pushed in the direction of the arrow X against the elastic force of the coil spring 70. It will be done. Tip 81 of the adjusting screw 80 screwed onto the hanging portion 79
is brought into contact with the front surface 82 of the base 42 of the housing 41, and the return position of the bracket 77, that is, the starting position of the surface 11' of the end face cutting detection head 11, is finely adjusted to the normal position.

The other functions are the same as those of the external diameter cutting tool B ₁ and the internal diameter cutting tool B ₃ , but in this case, the detection head 11 for end face cutting is provided for measuring the cutting edge during end face machining. , the operator selects the detection head 11 for end face cutting provided according to the processing content and performs the measurement operation without any hesitation as to which detection head should be used to measure the end face cutting tool B ₂ . I can do it.

(Effects of the Invention) The present invention has a headstock 1, and the headstock 1 is rotatably provided with a main shaft provided with a workpiece holding means such as a chuck, and is used for external machining of at least an outer diameter cutting tool B ₁ , etc. A tool rest T is provided on which internal cutting tools such as cutting tools and internal cutting tools B ₃ can be mounted.
The workpiece is moved by relatively moving the main spindle and the turret in a first direction such as the X-X axis parallel to the main spindle axis and in a second direction perpendicular to the main axis such as the Z-Z axis. In a machine tool for processing, a bending arm such as a detection arm 8 having a bent arm shape as a whole is swingably mounted on the headstock, and a measuring device main body such as a detection device main body 9 is attached to the tip of the bending arm. By the swinging motion of the bending arm, the headstock and the turret are retracted from the movement plane for machining, and the headstock and the turret are within the movement plane for machining and the A detection head for end face processing is provided on the outside of the measuring device body in the first direction, and a detection head for end face processing is provided on the outside of the measuring device main body, and a detection head is provided in the back direction in the second direction. A detection head for external machining and a detection head for internal machining are provided in such a manner that the detection head for external machining is disposed on the side closer to the tool post and the detection head for internal machining is disposed on the opposite side, and each of the above-mentioned Each of the detection heads is provided in such a way that the directions in which the measurement surfaces of the detection heads face do not intersect with each other, and the measurement surfaces are movable, and each of the detection heads and an automatic control device provided in the machine tool are connected via a signal transmission path. With this configuration, the blade edge position for three types of machining, outer diameter machining, inner diameter machining, and end face machining, can be measured with one detection device, which is extremely convenient.

Further, a detection head for end face machining is provided on the outside of the measuring device main body in the first direction, and a detection head for external machining and a detection head for internal diameter machining are provided facing back to the second direction. A detection head for external machining is provided on a side close to the tool rest, and a detection head for internal machining is arranged on the opposite side, with the measurement surfaces of each of the detection heads such as surfaces 10', 11', and 12' facing. Since the directions do not intersect with each other and the measurement surfaces are provided so that they can be pushed freely,
Each detection head is installed in a shape according to the processing content,
When measuring the position of the cutting edge of a tool used for external machining, end face machining, and internal diameter machining, the operator presses the cutting edge against the corresponding detection head according to the processing to be performed, and immediately determines the appropriate cutting edge position required for the relevant processing. can be detected.

In addition, each detection head is provided so that its measurement surface can be pushed freely, so when measuring the cutting edge,
It is possible to reduce the impact when the cutting edge comes into contact with the detection head, and prevent the occurrence of a situation where the cutting edge is damaged due to a collision between the cutting edge and the block, as in the case of measurement using a block. Not only can the measurement surface of each detection head be configured independently for each measurement direction, but the measurement device itself can be made larger as would be the case if multiple measurement surfaces were simply formed on a block. This makes it possible to eliminate the risk of measurement errors due to an increase in the size of the measurement surface and variations in measurement positions. In addition, not only can positioning to the measurement position be easily and accurately performed with a small driving force, but the measurement surface of each detection head only needs to be accurately machined in a single measurement direction and then mounted. , the manufacturing and assembly of the measuring device becomes easy. In addition, measurement errors caused by assembly and installation errors of one detection head or changes over time of the measurement surface do not affect measurement errors of other detection heads, providing a highly reliable cutting edge position detection device. You can.

Furthermore, when measuring the cutting edge, the main body of the detection device is positioned at the measurement position within the movement plane for machining the headstock and tool post and in front of the workpiece holding means, so that machining using the measured tool is not possible. However, the measurement is performed near the position where the cutting edge of the tool is measured, making it possible to set the cutting edge measurement position and the actual machining position extremely close to each other. This makes it possible to prevent as much as possible a decrease in machining accuracy due to errors in the drive system such as the tool post, and to easily realize high-precision machining including green jaw machining.

In addition, since the main body of the detection device is movably mounted on the tool post via a bending arm, it is possible to measure the cutting edge while taking into account the effects of thermal displacement between the headstock and the tool post. Since the measurement position can be set in front of the workpiece holding means using the bending arm while eliminating interference with the workpiece holding means, high-precision machining and tool rest can be achieved by bringing the cutting edge measurement position and the actual machining position closer together. It is now possible to measure the cutting edge while taking into account the influence of thermal displacement between the headstocks, making it possible to perform extremely high-precision machining that is not possible with conventional measuring devices.

In addition, by providing a cover means in the retracted position to protect the detection heads from cutting dust, the cover means protects each detection head from cutting dust such as cutting water and chips generated during machining of a workpiece when the cutting edge is not being measured. Since this protects the measuring device from occurring due to adhesion of cutting dust, it is possible to prevent failure of the measuring device and maintain proper measuring performance over a long period of time.

[Brief explanation of drawings]

Fig. 1 is a partially sectional side view of the main part of an embodiment of the present invention, Fig. 2 is a front view of the same, Fig. 3 is a side view of the swing motor mounting section, Fig. 4 is a sectional view of the same, and Fig. The figure is a side view of the lower limit stopper mounting part, Figure 6 is a front view of the same,
Fig. 7 is a plan view of the door attachment part, Fig. 8 is a side view of the same, Fig. 9 is an enlarged partially sectional plan view of the main body of the detection device, Fig. 10 is an enlarged front view of the same, and Fig. 11 is the same housing. FIG. 12 is an enlarged cross-sectional plan view of the base, and FIG. 12 is an enlarged side view thereof. (Explanation of symbols of main parts), 1... Headstock, 4
... Rotation axis, 7 ... Swing motor, 8 ... Detection arm, 9 ... Detection device main body, 10 ... Detection head (for outer diameter cutting), 11 ... Detection head (for end face cutting), 12 ...Detection head (for inner diameter cutting), 13...
...Cam, 26... Bulkhead, 27... Bulkhead, 28...
Through hole, 29...Through hole, 30...Door, 37...Cylinder, B ₁ ...Bite (for cutting outside diameter), B ₁ '...
Cutting edge (of the cutting tool), B ₂ ... Bit (for cutting the end face),
B ₂ ′... Cutting edge (of the cutting tool), B ₃ ... Cutting tool (for internal cutting), B ₃ ′... Cutting edge (of the cutting tool), T... Turret, X-X... Spindle center, A-A ...Center line (of the arm).

Claims (1)

[Scope of Claims] 1. A main spindle, the main spindle having a workpiece holding means rotatably provided therein, and a tool rest capable of mounting at least an external machining tool and an internal machining tool; In a machine tool that processes the workpiece by relatively moving the spindle and the tool rest in a first direction parallel to the spindle axis and a second direction perpendicular to the spindle, A bending arm having a bent arm shape is swingably mounted, and a measuring device main body is attached to the tip of the bending arm, and a measuring device main body is attached to the tip of the bending arm, and a measuring device body is attached to the tip of the bending arm. The measuring device is provided movably between a retracting position for retracting from a moving plane and a measuring position provided within the moving plane for machining the headstock and the tool rest and in front of the workpiece holding means. A detection head for end face machining is provided on the outside of the main body in the first direction, and a detection head for external machining and a detection head for inner diameter machining are provided facing back to the second direction. is provided on a side close to the tool rest with the detection head for inner diameter machining arranged on the opposite side thereof, and the measurement surfaces of the detection heads are arranged in such a manner that the directions in which the measurement surfaces thereof face do not intersect with each other, and the measurement surfaces are pushed. A cutting edge position detecting device for a machine tool, which is configured by connecting each of the detection heads and an automatic control device provided in the machine tool via a signal transmission path. 2 having a headstock, a main spindle provided with a workpiece holding means on the headstock, rotatably provided therein, a tool rest capable of mounting at least an external machining tool and an internal diameter machining tool, parallel to the axis of the main spindle; In a machine tool that processes the workpiece by relatively moving the spindle and the tool rest in a first direction and a second direction perpendicular to the spindle, the headstock has an arm shape that is entirely bent. A bending arm is swingably attached to the bending arm, and a measuring device main body is retracted from a movement plane for machining the headstock and the tool rest by the swinging movement of the bending arm. position and a measurement position provided in a movement plane for machining of the headstock and tool rest and in front of the workpiece holding means, A detection head for end face machining is provided in the first direction, a detection head for external machining and a detection head for internal machining are provided facing away from the second direction, and the detection head for external machining is located close to the tool post. The detection head for inner diameter machining is provided on the opposite side of the detection head, and the measurement surfaces of the detection heads are provided in such a manner that the directions in which their measurement surfaces face do not intersect with each other, and the measurement surfaces are movable. A cover means is provided at the retracted position to protect the detection head of the measuring device main body from cutting dust generated during the cutting operation of the workpiece held by the workpiece holding means, and is provided on each of the detection heads and the machine tool. A cutting edge position detection device for a machine tool that is connected to an automatic control device via a signal transmission line.