JP2010076026A - Attachment clamp device of boring and end-face-machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an attachment clamp device of a boring and end-face-machining apparatus capable of automatically executing the unclamping operation and the clamping operation when changing an attachment. <P>SOLUTION: The attachment clamp device comprises a nose nut 152 which has a female screw part 156 to be screwed with a male screw part 155 formed on an outer circumferential surface of a spindle 24 of a boring and end-face-machining apparatus, converts the rotation of the spindle 24 into the vertical motion, and attachably/detachably fixes a body 80 of the attachment 20 to/from the spindle 24, and a locking device 154 to selectively change the nose nut 152 to be rotatable or non-rotatable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a large structure, such as a propeller of a large ship or a stationary processing apparatus used for boss machining of a stator of a large turbine generator. The present invention relates to an attachment clamping device that automates a clamping operation.

  Large propellers for generators and stators for generators installed at power plants are larger than 10 meters in height. Processing such a large structure is impossible even for a large machining center.

Therefore, conventionally, a special processing apparatus is installed in a large structure for processing.
For example, Patent Document 1 proposes a machining apparatus that performs turning inside a large structure. In this machining apparatus, a swiveling column and a swivel drive are installed inside a large structure, and a machining head is attached to the swiveling column. The machining head includes a moving mechanism that moves the swivel column up and down and a moving mechanism that moves in the radial direction of the inner diameter portion.

When turning the inner peripheral portion of a large structure, the inner peripheral portion of the large tool is turned with a tool mounted on the swivel head while turning the swivel column and moving the machining head up and down. In this processing apparatus, an attachment can be attached to the processing head, and drilling can be performed with a drill or end mill attached to the attachment.
Japanese Patent No. 3605579

  However, the conventional technique for processing a large structure has the following problems.

  First, in order to perform different types of processing, such as using a boring attachment for turning the inner peripheral surface and using a facing attachment for turning the end surface, it is essential to replace the attachment. .

  However, since this type of conventional processing machine is a special processing machine that targets too large structures, unlike general-purpose machine tools such as machining centers, automation has not progressed. Since the operator had to manually perform operations such as clamping and unclamping the attachment by tightening or removing the bolts on the setup work table, it was inefficient and it took a long time to replace the attachment. .

  Accordingly, an object of the present invention is to provide an attachment clamping device for an upsetting machine capable of solving the problems of the prior art and automating unclamping and clamping operations when replacing attachments. .

  In order to achieve the above object, the present invention fixes a large structure to a surface plate as a workpiece, attaches an attachment to a spindle driven by a servo motor, and performs a hole machining and end surface machining on the workpiece. In the apparatus, the attachment device is detachably fixed to the main shaft, and includes a female screw portion that is screwed into a male screw portion formed on an outer peripheral surface of the main shaft, and converts the rotation of the main shaft to a vertical movement. And a nose nut for removably fixing the attachment main body to the main shaft, and a detent device for selectively switching the nose nut to be rotatable or non-rotatable.

  Further, according to the present invention, a flange portion having a protruding portion equally distributed on a circumference is formed at a lower end portion of the attachment, and the nose nut restrains the flange portion so that the protruding portion can pass therethrough. The groove has a clamp portion equally arranged on the circumference.

  Further, according to the present invention, the threaded portion of the main shaft and the nose nut are arranged so that the phase of the protruding portion and the groove is shifted when the nose nut is in the clamp position and the phase is matched when the nose nut is in the unclamp position. The thickness of the lead and the flange portion of the female screw portion is related to the gap between the upper surface of the main shaft and the nose nut.

  According to the present invention, the mechanism that clamps and unclamps the attachment to the main shaft employs a mechanism that converts the rotation of the main shaft to the vertical movement of the nose nut. Since the unclamping operation can be easily realized, the attachment clamping and unclamping operations can be automated.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of an attachment clamp device for a turning machine according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view showing an upsetting apparatus to which an attachment clamp apparatus according to the present invention is applied. FIG. 2 is a plan view of the stationary processing apparatus of FIG. 1 as viewed from above. 1 and 2, reference numeral 10 indicates a workpiece to be machined. In this embodiment, as the workpiece 10 of a large structure, a propeller for a large ship is taken as an example, and the inner peripheral surface of the boss portion 12 of the propeller and the end surface of the boss portion 12 are processed.

  The floor surface 11 is provided with pits 14 for accommodating the main body of the processing apparatus. The surface plate 15 is installed on the floor surface 11 so as to cross the pit 14. The workpiece 10 is installed on the surface plate 15 via a block 16, and the boss portion 12 is raised by the block 16 so that the propeller of the workpiece 10 does not contact the surface plate 15.

First, an outline of the configuration of the upsetting apparatus will be described.
The stationary machining apparatus according to the present embodiment is roughly divided into a machining apparatus main body 18 accommodated in the pit 14 and an attachment 20.

  The main body 18 of the upsetting apparatus includes a bed 21, a saddle 22 installed on the bed 21, and a headstock 23 installed on the saddle 22. The saddle 22 moves on the bed 21 in the front-rear direction (X-axis direction), and the headstock 23 can move on the saddle 22 in the left-right direction (Y-axis direction). The headstock 23 has a main shaft 24 that rotates the attachment 20, and the attachment 20 is detachably fixed to the main shaft 24 by an attachment clamp device described later. The attachment 20 shown in FIG. 1 is a boring attachment used for turning the inner peripheral surface of the boss portion 12 of the workpiece 10.

Hereinafter, each part of the upsetting apparatus according to the present embodiment will be described in detail.
The bed 21 is fixed to the bottom surface of the pit 14 via a leveling block 26. Guide rails 27 for guiding the saddle 22 are attached to the left and right sides of the upper surface of the bed 21. As shown in FIG. 2, the X-axis servomotor 28 drives the feed shaft mechanism that moves the saddle 22. The headstock 23 is guided by a guide rail 29 provided on the saddle 22. The feed shaft mechanism that moves the headstock 23 is driven by a Y-axis servomotor 30. In the stationary processing apparatus of this embodiment, the head stock 23 can accurately position an arbitrary position on the horizontal plane by simultaneous two-axis numerical control of the X axis and the Y axis.

  Next, FIG. 3 is a cross-sectional view showing the configuration of the head stock 23. In FIG. 3, reference numeral 32 indicates a headstock body. The interior of the head stock body 32 is hollow. A spindle support part 33 is formed integrally with the upper part of the spindle head body 32. The main shaft 24 is rotatably supported by a main shaft bearing 36 in the main shaft support portion 33.

  The attachment 20 is detachably fixed to the main shaft 24 by an attachment clamp device 38. The attachment clamp device 38 includes a nose nut 152 and a detent device 154 that prevents the nose nut 152 from rotating.

  Here, the attachment 20 rotates integrally with the main shaft 24, but in order to process the boss portion 12 of the workpiece 10, it is necessary to send a tool 82. Moreover, it is necessary to feed the tool 82 in two directions, that is, the axial direction and the radial direction. In the stationary processing apparatus of the present embodiment, since the servo motor as the power source is arranged on the head stock 23, two systems for transmitting the power to the attachment 20 are provided. When the attachment 20 is a boring attachment, the axial feed becomes a feed axis and the radial feed becomes a cutting axis. In the following description, a case where the attachment 20 is a bowling attachment will be described.

  Therefore, as shown in FIG. 3, a double transmission shaft including an inner transmission shaft 42 and a hollow transmission shaft 44 is provided at the center of the main shaft 24. The transmission shaft has a double structure because the inner transmission shaft 42 and the hollow transmission shaft 44 are each transmitted to the attachment 20 by the rotation of two servo motors 46 and 48 provided on the headstock 23. This is because it constitutes an axis. One system is a system that transmits the rotation of the first servo motor 46 to the inner transmission shaft 42 and transmits the rotation to the notch shaft of the attachment 20 via a meshing clutch and a universal joint. The other system is a system in which the rotation of the second servo motor 48 is transmitted to the hollow transmission shaft 44 and is transmitted to the feed shaft of the attachment 20 through a meshing clutch and a universal joint.

  Hereinafter, the respective drive transmission systems of the main shaft 24 and the attachment 20 will be described in order.

FIG. 4 shows a rotational drive mechanism of the spindle 24 provided on the spindle stock 23. 3 and 4, the worm wheel 60 is coaxially fixed to the lower end surface of the main shaft 24 by bolts. A worm 62 supported by bearings 61a to 61c is engaged with the worm wheel 60. An output shaft 65 of the main shaft driving servo motor 64 is connected to a gear shaft 66 via a coupling 67. A spur gear 68 is integrally formed on the gear shaft 66. A spur gear 69 is attached to one end of the worm 62 by a key not shown, and a spur gear 68 is engaged with the spur gear 69.
Next, FIG. 3 shows two systems of drive transmission mechanisms that transmit to the attachment 20.

  First, the rotation of the first servo motor 46 is transmitted to the inner transmission shaft 42 of the double transmission shaft as follows. The transmission shafts B 1 and B 2 are respectively supported in parallel by bearings, and one end of the transmission shaft B 1 is connected to the first servo motor 46. A spur gear 70 is attached to the other end of the transmission shaft B1. The spur gear 70 meshes with a spur gear 71 attached to the transmission shaft B2. A bevel gear 72 is attached to the tip of the transmission shaft B 2, and the bevel gear 72 meshes with a bevel gear 73 attached to the lower end of the inner transmission shaft 42. The spur gears 70 and 71 and the bevel gears 72 and 73 are all prevented from rotating with respect to each transmission shaft to which the spur gears 72 and 73 are attached.

  Similarly, the rotation of the second servomotor 48 is transmitted to the hollow rotating shaft 44 of the double transmission shaft as follows. The transmission shafts C1, C2, and C3 are respectively supported in parallel by bearings, and one end of the transmission shaft C1 is connected to the second servo motor 48. A spur gear 74 is attached to the transmission shaft C1, and the spur gear 74 meshes with a spur gear 75 attached to the transmission shaft C2. A spur gear 76 is attached to the transmission shaft C2, and the spur gear 76 meshes with a spur gear 77 attached to the transmission shaft C3. A bevel gear 78 is provided at the tip of the transmission shaft C 3, and the bevel gear 78 meshes with a bevel gear 79 attached to the lower end of the hollow rotary shaft 44. The spur gears 74 and 75 and the bevel gears 78 and 79 are all prevented from rotating with respect to each transmission shaft to which the spur gears 78 and 79 are attached.

Next, FIG. 5 shows a tool feed mechanism including a feed shaft and a cutting shaft provided in the attachment 20, and FIG. 6 shows a VI-VI cross section in FIG.
5 and 6, reference numeral 80 indicates the main body of the attachment 20. The attachment main body 80 is a long cylindrical body, and when attached to the main shaft 24, as shown in FIG. 1, the attachment main body 80 has a height that penetrates the boss 12 of the workpiece 10 from below and protrudes further upward. Therefore, the entire region and end face of the boss portion 12 can be processed. Moreover, the outer diameter of the attachment main body 80 is smaller than the inner diameter of the hole 12a of the boss part.

  As shown in FIG. 5, a passage 83 is formed in the attachment body 80 in the axial direction, and the moving block 84 to which the tool 82 is attached moves in the passage 83. In the passage 83, a spline shaft 85 constituting a cutting shaft and a ball screw shaft 86 constituting a feed shaft are arranged in parallel. A bearing support 85b and a boss portion 85c are formed integrally with the spline shaft 85 at the lower end portion of the spline shaft 85, and the boss portion 85c is connected to the universal joint 128 with a bolt. Similarly, a bearing support portion 86 b and a boss portion 86 c are formed integrally with the ball screw shaft 86 at the lower end portion of the ball screw shaft 86, and the boss portion 86 c is connected to the universal joint 138.

  The structure of the feed shaft in the attachment 20 will be described first. The moving block 84 is formed with holes 91 and 92 into which the spline shaft 85 and the ball screw shaft 86 are loosely fitted, respectively. Of these, a ball nut 93 is fixed to the upper opening of the hole 92. The ball nut 93 is screwed onto the ball screw shaft 86. Therefore, according to the feed shaft mechanism of the present embodiment, the rotation of the ball screw shaft 86 is converted into the linear motion in the axial direction of the moving block 84 by the ball nut 93, so that the tool 82 is moved in the axial direction together with the moving block 84. Can send. As shown in FIG. 6 showing a VI-VI cross section of FIG. 5, two guides 97 that guide the linear motion of the moving block 84 in the axial direction are fixed to the attachment main body 80. Sliding plates 98 a to 98 c that slide on three guide surfaces of the guide 97 are attached to the moving block 84. Reference numeral 99 indicates a sliding plate holding member that holds the sliding plate 98a.

Next, the configuration of the cutting shaft in the attachment 20 will be described with reference to FIGS.
First, in FIG. 6, the moving direction of the tool 82 by the cutting shaft is the radial direction of the attachment main body 80. In the moving block 84, the tool 82 is held by the tool holder 100 so as to face in the radial direction. The tool 84 is fixed to the tool holder 100 using a set screw 101. The tool holder 100 is inserted into a hole 102 extending in the radial direction in the moving block 84. Since the key 103 is engaged with the tool holder 100 and the rotation is restricted by the key 103, the tool holder 100 cannot be rotated, but advancing and retreating movements with the hole 102 as a guide is permitted. . The tool holder 100 is moved in and out by a mechanism in which the following worm gear and a screw formed on the tool holder 100 are combined.

  In FIG. 6, a worm 104 is fitted to the spline shaft 85. A worm wheel 105 meshing with the worm 104 is rotatably attached to the moving block 84 via a bearing 106. A female screw is formed on the inner diameter portion of the worm wheel 105, and a male screw is formed on the tool holder 100.

  Therefore, according to the cutting shaft mechanism of the present embodiment, the rotation of the spline shaft 85 is largely decelerated by the worm 104 and the worm wheel 105, and the tool holder is engaged by the engagement of the internal thread of the worm wheel 105 and the external thread of the tool holder 100. Converted to 100 radial advance and retreat movements. Thereby, in the attachment 20, the cutting amount of the tool 82 with respect to a workpiece | work can be given. Needless to say, the rotational transmission by the spline shaft 85 is compatible with the movement of the moving block 84 by the ball screw shaft 86.

  Next, the power transmission system from the headstock 23 to the spline shaft 85 and the ball screw shaft 86 will be described with reference to FIGS.

  The double transmission shaft provided coaxially with the main shaft 24 includes an inner transmission shaft 42 and a hollow transmission shaft 44 that accommodates the inner transmission shaft 42 coaxially. As shown in FIG. 3, the inner transmission shaft 42 is rotatably supported by bearings 110a and 110b fixed to the hollow transmission shaft 44 at upper and lower ends thereof. The hollow transmission shaft 44 is rotatably supported by bearings 112 a and 112 b fixed to the main shaft 24. Therefore, the inner transmission shaft 42 can rotate independently of the hollow transmission shaft 44 and the main shaft 24, and the hollow transmission shaft 44 can also rotate independently of the inner transmission shaft 42 and the main shaft 24.

  Such a double transmission shaft is connected to the spline shaft 85 and the ball screw shaft 86 by changing the transmission type from a coaxial two-axis transmission to a parallel two-axis transmission by the following transmission coupling mechanism.

In FIG. 5, a claw 115 that forms an element of a meshing clutch is formed at the shaft end portion 114 at the upper end of the inner transmission shaft 42. Further, one tooth of the mesh clutch 117 is formed at the upper end of the hollow transmission shaft 44.
On the other hand, the following coaxial double joint shaft is attached to the lower part of the attachment main body 80 via an attachment member 116. That is, this double joint shaft is composed of an inner joint shaft 118 and a hollow outer joint shaft 120. Among these, the inner relay shaft 118 is rotatably supported by a bearing 121 fixed to the hollow outer relay shaft 120. The outer relay shaft 120 is rotatably supported by a bearing 122 fixed to the support member 116.

First, the transmission system from the inner transmission shaft 42 and the inner relay shaft 118 to the spline shaft 85 will be described.
At the lower end of the inner joint shaft 118, a groove 123 is formed which engages with the above-described pawl 115 and forms a meshing clutch element, and a spur gear 124 is integrated with the inner joint shaft 118 at the upper end portion of the inner joint shaft 118. Is formed.

  A drive-side universal joint 126 and a driven-side universal joint 128 form a pair at a position eccentric from the inner intermediate shaft 118. The universal joint 126 and the universal joint 128 are eccentric from each other and are connected by an inclined intermediate shaft 129. In the universal joint 126, a spur gear 134 is formed at the tip of the support shaft 130 on the outer ring. The spur gear 134 is fixed with a bolt, and the support shaft 130 is rotatably supported by a bearing 131. The inner ring side of the universal joint 126 is connected to the intermediate shaft 129. In the universal joint 128 on the driven side, the outer ring side is supported by the bearing 132 via the bearing support portion 85b and the boss portion 85c, and the inner ring side is connected to the intermediate shaft 129. The spur gear 134 is engaged with the spur gear 124 at the tip of the inner intermediate shaft 118. Therefore, the rotation of the inner transmission shaft 42 is transmitted from the inner relay shaft 118 to the spline shaft 85 via the pair of universal joints 126 and 128, and the above-described cutting shaft is operated.

Next, the transmission system from the hollow transmission shaft 44 and the outer joint shaft 120 to the ball screw shaft 86 will be described.
At the lower end of the outer relay shaft 120, teeth forming the elements of the mesh clutch 117 are formed together with the teeth formed at the upper end of the hollow transmission shaft 44, and the inner relay shaft 118 is idled at the upper end of the outer relay shaft 120. The spur gear 135 is integrally formed with the inner relay shaft 118 by fitting.

  A drive-side universal joint 136 and a driven-side universal joint 138 make a pair at a position eccentric from the outer joint shaft 120. The universal joint 136 and the universal joint 138 are eccentric from each other and are connected by an inclined intermediate shaft 139. In the universal joint 136, an outer ring is formed at the tip of the support shaft 140. A spur gear 144 is fixed to the outer ring with a bolt, and the support shaft 140 is rotatably supported by a bearing 141. The inner ring side of the universal joint 136 is connected to the intermediate shaft 139. In the universal joint 138 on the driven side, the outer ring side is supported by the bearing 142 via the bearing support part 86b and the boss part 86c, and the inner ring side is connected to the intermediate shaft 139. The spur gear 144 of the outer ring of the universal joint 136 on the drive side is adapted to mesh with the spur gear 135 of the outer joint shaft 120. Accordingly, the rotation of the hollow transmission shaft 44 is transmitted from the outer joint shaft 120 to the ball screw shaft 86 through the pair of universal joints 136 and 138, and the above-described feed shaft is operated.

The attachment 20 described above is fixed to the tip end of the main shaft 24 by using an attachment clamp device described below, and conversely, by releasing the clamp, it can be removed for attachment replacement.
FIG. 7 shows the configuration of the attachment clamp device 38 according to the present embodiment. In FIG. 7, the attachment clamp device 38 includes a nose nut 152 and a detent device 154. The nose nut 152 is screwed into the main shaft 24, and by using a screw mechanism, the rotation of the main shaft 24 is converted into the vertical movement of the nose nut 152 to perform clamping and unclamping operations. The detent device 154 is a device for restricting the rotation of the nose nut 152 in order to move it up and down.

A male screw portion 155 is formed on the upper outer peripheral surface of the main shaft 24. The nose nut 152 is a cylindrical nut, and an internal thread 156 is formed on the inner periphery thereof. The nose nut 152 is formed with a clamp portion 158 that restrains the flange portion 174 formed at the lower end of the attachment main body 80. The clamp portion 158 has a flange shape protruding inward.
A spindle support part 33 is provided at the upper end of the headstock body 32, and a space in which the nose nut 152 can move up and down is provided between the spindle 24 and the inner peripheral surface of the spindle support part 33. ing.

  The detent device 154 is a device whose main element is a cylinder 162 that puts and removes a pin 164 in a long groove 163 on the outer peripheral surface of the nose nut 152. In this case, the long groove 163 is a groove that is long in the axial direction of the nose nut 152. The pin 164 constitutes a part of the piston 165 of the cylinder 162. A piston rod 167 constituting a part of the piston 165 protrudes from the cylinder cover 166, and a dog 168 is provided on the piston rod 167. Two limit switches 170a and 170b that are turned on / off by the dog 168 to detect the position of the pin 164 are arranged at predetermined positions. In this case, when pressure oil is supplied from the inlet port A, the pin 164 protrudes. Since the limit switch 170a is turned on when the pin 164 is in the position where the long groove 163 is entered as shown in FIG. 7, it can be confirmed whether the pin has entered the long groove 163 normally. On the other hand, when pressurized oil is supplied from the inlet port B, the pin 164 is detached from the long groove 163. Since the limit switch 170b is turned on, it can be confirmed that the release operation has been normally performed. When attaching / detaching the attachment 20 to / from the main shaft 24, the pin 164 is in the position shown in FIG. Since the main shaft 24 rotates during the processing of the workpiece, the pin 164 is detached from the long groove 163.

  Here, FIG. 8 shows the phase matching relationship between the flange 174 at the lower end of the attachment body 80 and the nose nut 152 when the attachment body 80 is clamped with the nose nut 152 or attached / detached. 8A shows a phase relationship when the attachment main end 80 is detached, and FIG. 8B shows a phase relationship when the attachment main body 80 is clamped.

  A flange portion 174 having a structure as shown in FIG. 8 is formed at the lower end portion of the attachment main body 80. In this embodiment, four protruding portions 176 are arranged at equal intervals on the outer peripheral portion of the flange portion 174 in a symmetrical manner every 90 °.

  In the clamp part 158 of the nose nut 152, four grooves 178 are equally arranged approximately every 90 °. The groove 178 has a contour that allows the protruding portion 176 to pass therethrough.

  Therefore, when the attachment main body 80 is attached to or removed from the main shaft 24, the phases of the protruding portion 176 and the groove 178 may be matched. Further, in the present embodiment, when the main shaft 24 turns by an integral multiple of about 45 °, as shown in FIG. 8B, the protruding portion 176 is located in the middle of the adjacent groove 178, and at this time, the flange portion 174 Is clamped. In order to adjust or shift the phase in this way, in FIG. 7, the thickness HN of the lead or flange portion 174 of the male screw portion 155 of the main shaft 24 and the gap H between the upper surface of the main shaft 24 and the nose nut 152 Relationship is set.

Next, a workpiece machining procedure will be described.
First, an outline of a workpiece machining procedure will be described.
Workpiece processing is performed in the order of setup such as workpiece installation, attachment attachment, and processing. When the boss portion 12 of the propeller is processed as in this embodiment, the processing proceeds in the order of end surface processing of the boss portion 12 and turning of the inner peripheral surface of the boss portion 12.

  There are two types of attachments: a facing attachment that performs end face machining and a boring attachment that performs turning of the inner peripheral surface, and the attachment is changed from the facing attachment to the boring attachment along the way. Regardless, the description will focus on the common points, and the feature points depending on the type of processing will be mentioned as appropriate.

Setup
First, in FIGS. 1 and 2, the workpiece 10 is fixed so that its axis is perpendicular to the surface plate 15. After the workpiece 10 is installed, the headstock 23 is moved directly below the workpiece 10. This movement of the headstock 23 activates the X-axis servomotor 28 and the Y-axis servomotor 30 to feed the saddle 22 and the headstock 23 so that the center of the main spindle 24 of the headstock 23 coincides with the center of the work 10. The headstock 23 is roughly positioned.

Attachment attachment, clamp
The attachment 20 is suspended by a crane and lowered from directly above the workpiece 10 through the hole 12a of the boss portion 12.

  With the protrusion 176 of the flange portion 174 at the lower end of the attachment body 80 and the groove 178 in the clamp portion 158 of the nose nut 152 in phase (see FIG. 8A), the attachment body 80 is moved to the nose nut. When placed on 152, the protrusion 176 can pass through the groove 178. When the attachment main body 80 is placed on the main shaft 24, the double transmission shaft on the main shaft 24 side is clutch-connected to the double relay shaft on the attachment side.

  That is, in FIGS. 3 and 5, in the double joint shaft incorporated in the lower part of the attachment main body 80, the groove 123 of the inner joint shaft 118 and the claw 115 at the shaft end 114 of the inner transmission shaft 42 are engaged with each other. The teeth at the lower end of the outer relay shaft 120 constituting the clutch 117 mesh with the teeth at the upper end of the hollow transmission shaft 44. Thereby, the double relay shaft on the attachment 20 side is connected to the double transmission shaft on the main shaft 24 side in a state where power can be transmitted.

  Next, in FIG. 3, FIG. 4, and FIG. 7, the spindle driving servo motor 64 is activated, and the spindle 24 turns in an integer multiple positive rotation direction of about 45 °. At this time, pressure oil is supplied from the port A to the cylinder 162 of the detent device 154, and the pin 164 is in the advanced position. In this position, the head of the pin 164 is engaged from the long groove 163 of the nose nut 152, and the rotation of the nose nut 152 is restricted. Moreover, since the female screw 156 of the nose nut 152 is screwed into the male screw portion 155 of the main shaft 24, the nose nut 154 is lowered when the main shaft 24 is rotated forward, and is raised when the main shaft 24 is rotated reversely. Since the long groove 163 is long in the vertical direction, the pin 164 does not interfere with the vertical movement of the nose nut 154.

  When the main shaft 24 turns in the forward rotation direction, the clamp portion 158 of the nose nut 152 descends and eventually presses the flange portion 174 of the attachment main body 80. In this embodiment, when the main shaft 24 is rotated by an integral multiple of about 45 °, as shown in FIG. 8B, the protruding portion 176 is positioned in the middle of the adjacent groove 178, and at this time, the flange portion 174 is clamped. The

When the main shaft 24 is rotated to clamp the attachment main body 80, the main shaft driving servo motor 64 is controlled under the torque control mode. When the torque necessary for clamping is set in advance and the nose nut 152 starts to restrain the flange portion 174 of the attachment body 80, the torque of the spindle driving servo motor 64 increases, and eventually reaches the set torque, after a predetermined time has passed. Is completed, the spindle driving servomotor 64 is stopped. Thereafter, the state in which the nose nut 152 is fastened to the main shaft 24 is maintained, and the attachment body 80 is firmly clamped by the nose nut 152.
Thereafter, in FIG. 7, in the cylinder 162 of the detent device 154, the pin 164 is retracted, and the head of the pin 164 is detached from the long groove 163 of the nose nut 152. Thereafter, the attachment main body 80 can be rotated integrally with the main shaft 24 while being clamped by the nose nut 152.

Unclamping and removing the attachment
The operation of unclamping the attachment body 80 is the reverse of the above-described clamping operation.

First, the servo motor 64 for driving the spindle is driven, and the spindle 24 is rotated to a position where the long groove 163 of the nose nut 152 engages with the pin 164. Next, in the cylinder 162 of the detent device 154, the pin 164 moves forward, and the head of the pin 164 engages with the long groove 163 of the nose nut 152. Thereafter, the rotation of the nose nut 152 is regulated by the pin 164. Next, when the main shaft 24 turns in the reverse direction, the clamp part 158 of the nose nut 152 rises and lowers, and the clamp of the flange part 174 of the attachment body 80 is eventually released. . In the present embodiment, when the main shaft 24 turns 45 °, the phases of the adjacent groove 178 and the protruding portion 176 coincide with each other in FIG.

  The angle at which the long groove 163 of the nose nut 152 engages with the pin 164 and the angle at which the phases of the adjacent groove 178 and the protruding portion 176 coincide with each other are memorized by the servo motor 64 for driving the main shaft. Can be rotated.

  Thereafter, the attachment 20 is hung with a crane and extracted from the hole 12 a of the boss portion 12 of the workpiece 10. At this time, the meshing clutch that connects the double transmission shaft on the main shaft 24 side and the double joint shaft on the attachment side can be cut only by pulling up the attachment 20.

Processing of workpiece by attachment In FIGS. 1 and 5, in processing of the end surface 12 b of the boss portion 12, a facing attachment (not shown) is attached to the main shaft 24 instead of the attachment 20 shown in the drawing.

  In the end face processing, as a preparation, a dial gauge or the like is attached to the attachment, and the shape of the inner peripheral surface of the boss portion 12 is measured while rotating the attachment. From this measurement result, the position of the axial center of the boss portion 12 is calculated.

  Then, the X-axis servo motor 28 and the Y-axis servo motor 30 are started, the positions of the saddle 22 and the headstock 23 are finely adjusted, and the boss portion 12 and the attachment are centered. Accurate centering can be performed by simultaneous 2-axis numerical control of the X and Y axes.

  Thereafter, the facing attachment is rotated together with the main shaft 24, and the tool is fed in the axial direction to be cut into the end face 12b. Then, the end face 12b can be turned by sending the tool in the radial direction.

  Next, the attachment is replaced with the attachment 20 shown in FIGS. Moreover, the steady rest shown in FIG. 9 is attached.

  The steady rest includes a spline shaft 180, a fixed portion 182, leg portions 184a and 184b, and a ring portion 185. A plurality of positioning pins 186 are equally arranged on the circumference of the flange-shaped fixing portion 182, and the positioning pins 186 are fitted into pin holes 187 formed at the top of the attachment main body 80. A sleeve 188 is fitted to the spline shaft 180 so as to be movable up and down, and the sleeve 188 is held by a ring portion 185 via a bearing. The ring portion 185 is fixed to the upper ends of the leg portions 184a and 184b with bolts. The lower end portions of the leg portions 184a and 184b are adapted to engage with the spigot portions provided on the upper end surface of the boss portion 10 of the workpiece 10.

  In such a steady rest, since the spline shaft 180 is held so as not to be shaken by the ring portion 185 supported by the legs 184a and 184b, the attachment 20 is located on the center line of the workpiece 10 at the above centered position. Will rotate. Since the sleeve 188 fitted to the spline shaft 180 can be adjusted in the vertical position, the sleeve 188 can be fixed at an appropriate position with the set screw 190.

  In the process of turning the inner diameter of the boss portion 12, the main shaft 24 is rotated, and the tool 82 of the attachment 20 is sent in the radial direction by the cutting shaft to be cut into the inner diameter surface of the boss portion 12. And the tool 82 is sent to an axial direction with a feed shaft, and the whole internal diameter part of the boss | hub part 12 is turned.

  In this upsetting apparatus, a first servo motor 46 and a second servo motor 48 for driving a cutting shaft and a feed shaft in the attachment 20 are provided on the spindle stock 23. The main shaft 24 is coaxially provided with a double transmission shaft comprising an inner transmission shaft 42 and a hollow transmission shaft 44, and the attachment 20 is provided with a double joint shaft comprising an inner relay shaft 118 and an outer relay shaft 120. ing.

  The rotation of the first servo motor 46 is transmitted from the inner transmission shaft 42 to the inner relay shaft 118 through the meshing clutch, and further to the spline shaft 85 through the pair of universal joints 126 and 128, and is attached to the attachment 20 by the worm mechanism described above. It is designed to operate the cutting axis.

  On the other hand, the rotation of the second servo motor 48 is transmitted from the hollow transmission shaft 42 to the outer relay shaft 120 via the meshing clutch, and further to the ball screw shaft 86 via the pair of universal joints 136 and 138. The feed shaft is operated by a nut mechanism.

  Since the two drive transmission systems connected to such a notch shaft and feed shaft are mechanisms that directly transmit to the attachment 20 from the first servo motor 46 and the second servo motor 48 installed on the headstock 23, As in the prior art, the configuration of the drive transmission mechanism is fundamentally different from that in which a motor is provided on a machining head arranged in a boss portion of a workpiece.

  In other words, when a motor is provided on the machining head as in the past, it is necessary to supply power and transfer control signals to the motor that rotates with the machining head. Maintenance was required to maintain the reliability.

  On the other hand, in this upsetting apparatus, the first servo motor 46 and the second servo motor 48 that are fixedly disposed on the headstock 23 side may be controlled, so that the notch shaft and the feed shaft of the attachment 20 can be easily provided. Thus, numerical control with high reliability can be realized as in a general machine tool. In addition to end face machining and internal diameter turning, taper hole machining by simultaneous biaxial control can be performed with high accuracy.

Replacement of Attachment As described above, the mechanism for clamping and unclamping the attachment 20 to the main shaft 24 employs a mechanism that converts the rotation of the main shaft 24 into the vertical movement of the nose nut 152. . For this reason, by controlling the turning operation of the main shaft 24, the clamping and unclamping operations can be easily realized, so that the attachment clamping and unclamping operations can be automated.

  In addition, as described above, it is unnecessary to attach a motor for driving the incision shaft and the feed shaft to the attachment 20, and the attachment structure can be made into a simple columnar shape, the incision shaft, and the feed shaft. Since the shaft transmission system is intermittently realized by a clutch that engages only by the vertical movement of the attachment, attachment replacement can be easily performed.

It is sectional drawing which shows the stationary processing apparatus with which the attachment clamp apparatus of this invention is applied. It is a top view of the same turning processing apparatus. It is sectional drawing of the headstock with which the same turning processing apparatus is provided. The top view which shows the drive transmission mechanism of the main shaft in a head stock. It is a longitudinal cross-sectional view of the attachment used with the same turning processing apparatus. It is VI-VI sectional drawing in FIG. It is sectional drawing which shows the structure of the attachment clamp apparatus by one Embodiment of this invention. The figure which shows the phase matching relationship of the nose nut and attachment in the attachment clamp apparatus. Sectional drawing which shows the steadying of an attachment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Work 12 Boss part 15 Surface plate 20 Attachment 22 Saddle 23 Main stand 24 Spindle 28 X-axis servomotor 30 Y-axis servomotor 38 Attachment clamp apparatus 42 Inner power transmission shaft 44 Hollow power transmission shaft 46 1st servomotor 48 2nd servomotor 60 Worm wheel 80 Attachment body 82 Tool 85 Spline shaft 86 Ball screw shaft 93 Ball nut 118 Inner joint shaft 120 Outer joint shaft 152 Nose nut 154 Non-rotating device

Claims (3)

A large structure is fixed to the surface plate as a workpiece, an attachment is attached to the spindle driven by a servo motor, and the attachment is detachably fixed to the spindle in a boring machine that performs hole machining and end face machining on the workpiece. A clamping device,
A nose nut having a female thread portion that is threadedly engaged with a male thread portion formed on an outer peripheral surface of the main shaft, and reversibly rotating the main shaft to fix the attachment body to the main shaft;
A detent device that selectively switches the nose nut to be rotatable or non-rotatable;
An attachment clamp device comprising:   A flange portion having a protruding portion equally distributed on the circumference is formed at a lower end portion of the attachment, the nose nut restrains the flange portion, and a groove through which the protruding portion can pass is formed on the circumference. The attachment clamp device according to claim 1, further comprising clamp portions arranged at equal intervals.   Leads and flanges of the screw portion of the main shaft and the female screw portion of the nose nut so that the phase of the protruding portion and the groove are shifted when the nose nut is in the clamp position and the phase is matched when the nose nut is in the unclamp position The attachment clamp device according to claim 2, wherein the thickness of the portion is related to the clearance between the upper surface of the main shaft and the nose nut.

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