JP2001198751A - Vertical machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tool magazine device which has a movable cover with which a vertical machine tool can position with high precision, and which can accelerate the tool change time and simplify the structure. SOLUTION: A main shaft head 6 which is vertically movable is arranged between a first slider 4 which is arranged on a bed 1 and longitudinally movable, a second slider 5 laterally movable, and a pair of guide rails 31, 41 with which the second slider 5 is laterally movable. A movable cover 91 is mounted on a magazine plate 72 so as to turn integrally with the magazine plate 72 and to close an open section of a cover device 90 when the magazine plate 72 is at a resting position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical machine tool for rotating a tool spindle around a vertical axis and a machine tool having a cover for isolating a tool magazine device from a machining area.

[0002]

2. Description of the Related Art There is known a vertical machine tool in which a spindle head or a tool spindle moves in three orthogonal directions of front and rear, left and right, and up and down to process a workpiece mounted on a jig device fixed on a bed. ing. As a configuration of this vertical machine tool, a first slider provided on a bed and movable in a first horizontal direction and a first slider stacked on the first slider and movable in a horizontal second direction at right angles to the first direction are provided. The first slider, the second slider, and a jig device disposed below the respective guide rails of the first slider, the second slider, and the main spindle head are provided. Are known. In this conventional vertical machine tool, a main spindle head is vertically movably disposed on one side of a pair of guide rails that enable the second slider to move in the left-right direction, opposite to the other guide rail. Was. Also,
In some other vertical machine tools, the spindle head returns the tool directly to the tool magazine device, and the spindle head removes the tool directly from the tool magazine device. The area where the tool magazine device is installed is separated from the processing area by a cover device surrounding the processing area. The cover device has an opening / closing cover element (movable cover) that allows the spindle to enter the tool magazine device installation area. This cover element was normally driven by a hydraulic cylinder.

[0003]

As described above, in the conventional vertical machine tool, one of the pair of guide rails that enables the second slider to move in the left-right direction is opposite to the other guide rail. That is, the spindle head is arranged outside the pair of guide rails so as to be movable in the vertical direction. The second slider receives a leftward propulsive force from the ball screw when traveling leftward, and receives a rightward frictional resistance from a pair of guide rails. Due to the differences, the frictional resistance exerted by the individual guide rails is not the same. Further, since the points of action of the propulsive force and the frictional resistance acting on the second slider are separated, they act as a rotational moment, and slightly turn the second slider. Also, the second
When the slider moves to the right, the force relationship is opposite to that when the slider moves to the left. As a result, the second slider is turned in the opposite direction when moved and positioned in the leftward direction and when moved and positioned in the rightward direction. Since the center of this rotation is between the pair of guide rails, in the case of a configuration in which the spindle head is disposed outside these guide rails, a positioning error in the left-right movement direction occurs, and the machining accuracy deteriorates. Further, in the round processing by contouring, the shape accuracy of the workpiece is deteriorated by switching the quadrants of the XY coordinates.

When a cutting force is applied to the spindle head, the force acting on the guide rail closer to the spindle head increases, and the deformation of the guide rail increases. Further, since the spindle head is overhanging from the guide rail, the deformation of the guide rail is enlarged at the position of the spindle head. For example, in rough boring, a cutting thrust force is applied in a direction that causes the spindle head to float upward. In this case, the force acting on the guide rail closer to the spindle head is greater than the cutting thrust force acting on the spindle head due to the principle of leverage with the distant guide rail as a fulcrum. In addition, since the mass of the spindle head acts on the guide rail of the second slider on the spindle head side, the guide rail on the spindle head side is greatly worn. Also, since the spindle head is overhanging on the guide rail,
The second slider is structurally large and its mass is increased, so that the feed speed and the feed acceleration cannot be increased.

[0005]

In order to solve the above-mentioned problems of the prior art, a vertical machine tool according to claim 1 or 2 has a first slider movable on a bed in a first horizontal direction. A second slider movable in a horizontal direction perpendicular to the first direction is laminated on the second slider, and the rotary tool main shaft is guided by the second slider so as to be movable in a vertical direction. In this configuration, the tool spindle is positioned between the pair of guide rails that enable the second slider to move in the second direction. That is, the tool spindle is arranged so as to be located between the pair of guide rails. Thus, as described in the above-described problem of the present invention, the second slider is turned in the opposite direction between when the second slider is positioned in the leftward direction and when the second slider is positioned in the rightward direction. Since the center of rotation of the slider is located between the guide rails, there is almost no positioning error between the left and right of the spindle head.

Further, when a reaction force of a thrust force due to the cutting is applied in a direction that causes the tool spindle to float upward, the tool slider is positioned substantially at the center of the pair of guide rails, so that the second slider is moved in the left-right direction. The reaction force is substantially evenly distributed to the pair of movable guide rails, the deformation of the guide rails is suppressed, and the deformation amount of the guide rails does not increase at the tool spindle position. Further, since the guide rail is positioned so as to straddle the processing point of the workpiece, the transmission path of the cutting force between the workpiece and the tool spindle is shortened, and the rigidity is improved. In addition, the mass of the slide system including the second slider and the tool spindle mounted on the second slider is substantially evenly distributed to the pair of guide rails that enable the second slider to move in the left-right direction. Be even.

According to a third aspect of the present invention, there is provided a tool magazine device according to the first or second aspect, wherein the tool magazine device is rotatable about an axis parallel to the axis of the tool spindle and exchanges tools with the tool spindle. A cover device for isolating the tool magazine device from the processing area when the tool magazine device is in the rest position, wherein the cover device is configured to rotate the tool magazine device from the rest position to a tool attachment / detachment position cooperating with the tool spindle. An allowable opening is formed, and a movable cover that is rotatable integrally with the tool magazine device and closes an opening of the cover device when the tool magazine device is in a rest position is attached to the magazine. Features. The movable cover rotates integrally with the tool magazine, eliminating the time required for opening and closing the movable cover, thereby simplifying the structure and shortening the tool replacement time.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The basic configuration of the machine tool of the present invention is, as shown in FIGS. 1 and 2, a fixture for fixing a workpiece 2 on the front side (operator side) of the bottom of a U-shaped bed 1 when the machine is viewed from the front. The fixture device 3 is attached. Bed 1
A vertical unit device 9 is attached to the upper part on the front side of the device. A tool magazine device 7 to be described later is mounted on the bed 1 via a plate 8 at an upper portion on the back side of the bed 1. A horizontal unit device 10 is attached to a bottom portion on the back side of the bed 1.

The vertical unit device 9 and the horizontal unit device 10 will be described with reference to FIGS. The vertical unit device 9 mainly includes a first slider 4 and a second slider 5.
And a spindle head 6. Vertical unit 9
Is formed of a lower portion 1a, a left side portion 1b, and a right side portion 1c, and has a U-shape. A guide rail 11 is fixed to the upper part 1b 'of the left side surface part 1b in the front-rear direction (Y-axis direction). A guide rail 21 is fixed to an upper portion 1c 'of the right side surface portion 1c in parallel with the guide rail 11. The first on the guide rails 11 and 21
A slider 4 is slidably supported. At the substantially center of the first slider 4, a rectangular window 4a is formed. First
Guide rails 31 and 41 are provided on the upper side of the slider 4 at right angles to the guide rails 11 and 21 on both sides of the window 4a.
Direction). The second slider 5 is slidably supported on the guide rails 31 and 41. At four corners of the lower surface of the second slider 5, guide blocks 32 and 32 ′ engaging with the guide rail 31 and the guide rail 41
Are fixed to the slide blocks 42 and 42 '.

A rectangular window 5a is formed at the center of the second slider 5, so that the spindle head 6 can move up and down. The second slider 5 is formed with a vertical plate parallel to the guide rails 31 and 41 and along one side of the guide rails to form a vertical surface 5b. Guide rails 51 and 61 are fixed to the vertical surface 5b in the vertical direction (Z-axis direction). The spindle head 6 is slidably supported by the guide rails 51 and 61.

Guide rails 11 and 21 of first slider 4
Are parallel to each other to form projections 16 and 26,
A pair of nuts 15 and 25 are fixed thereto. The pair of nuts 15 and 25 have a pair of ball screws 13 and 23, respectively.
Are engaged. A pair of ball screws 13, 23 are provided on the upper part 1 b ′, 1 c ′ of the bed 1, on the guide rail 11,
It is rotatably supported in parallel with these outside the outside. The pair of ball screws 13 and 23 are coupled so as to be rotationally driven by a pair of Y-axis direction feed servo motors 14 and 24.

Guide rails 31, 41 of the second slider 5
Are parallel to each other to form projections 36, 46,
A pair of nuts 35 and 45 are fixed thereto. A pair of nuts 35 and 45 are provided with a pair of ball screws 33 and 43, respectively.
Are engaged. The pair of ball screws 33, 43
It is supported on the upper part of the slider outside the guide rails 31 and 41 so as to be rotatable in parallel with them. The pair of ball screws 33 and 43 are a pair of X-axis direction feed servomotors 34,
It is coupled so as to be driven to rotate by 44. The spindle head has a projection 56 on which a nut 55 is fixed. Nut 55 has ball screw 53
Are engaged. The ball screw 53 is rotatably supported in parallel with the vertical surface 5b of the second slider. The ball screw 53 is coupled so as to be driven to rotate by a Z-axis direction feed servomotor 54.

The horizontal unit device 10 includes a horizontal tool spindle 1.
02, a tool 103 is attached to the front of the tool spindle 102, is positioned in the X-axis direction, the Y-axis direction, and the Z-axis direction by a numerical controller, and can perform machining on the workpiece 2. It is a processing device. This vertical unit device 1
Numeral 0 is installed at the bottom of the bed 1 on the rear side. This is because the tool magazine device 7 is suspended from the top of the bed 1 and a space is formed at the bottom of the bed 1 so that it can be installed. As a result, the side surface of the workpiece 2 that cannot be machined by the vertical unit device 9 can be machined.

As shown in FIG. 3, FIG. 4, and FIG. 6 to FIG. 8, the tool magazine device 7 is attached across the upper portions 1b 'and 1c' on the back side of the bed 1 via the plate 8. . The tool magazine device 7 mainly includes a speed reducer 71 suspended from the plate 8, a magazine plate 72, and a servomotor 73. A magazine plate 72 is attached to the output shaft of the speed reducer 71. Reduction gear 7
A servo motor 73 is attached to the other end of the magazine plate 1 so that the magazine plate 72 is indexed at a predetermined angle. The magazine plate 72 has a large number of substantially semicircular tool receiving portions 74a to 74d recessed from the outer peripheral portion toward the center.
4l is formed radially from the center 72a of the magazine plate 72 on the circumference excluding a part of the circumference. The semicircular tool accommodating portions 74a to 74l are formed with projections 75 which engage with the annular groove of the tool 80b along the inner peripheral surface thereof. Thereby, the movement of the tool 80b in the axial direction is restricted.

The magazine plate 72 is provided with a key 76 for engaging with a key groove of the tool 80b. As a result, the tool 80b does not rotate around its axis in the storage state on the tool magazine. The magazine plate 72 is provided with an engraved groove 72b milled from the lower side of the tool magazine plate 72 in the vicinity of each tool accommodating portion. A claw 77 is attached to the engraved groove 72b so as to be rotatable around the axis of the pin 78 by a threaded pin 78. Claws 77
Is inclined by a spring 79 so that the tool 80b can be easily fitted. Thereby, the tool 8
Ob does not fall out of the tool storage portion 74b. The front of the machine is a cover (not shown) that can be opened and closed to carry the work in.
Is installed. At the top of the bed 1, a wind-up type cover is installed in the X-axis direction and the Y-axis direction,
The closed state can be maintained even if the spindle head 6 moves. A cover 90 is fixed inside the left and right side surfaces 1b and 1c of the bed 1 in parallel with the X axis. Portions of the magazine plate 72 other than the tool storage portions 74a to 74l are:
A linear portion 72c is formed. The movable cover 91 is fixed to the linear portion 72c, and turns integrally with the magazine plate 72. The cover 90 allows the movable cover 91 to rotate vertically and pivotally, and has a tool take-out window 90a closed by the cover 91. A bellows cover is provided between the cover 90 and the horizontal unit 10,
The closed state is maintained even when the spindle head of the horizontal unit device 10 moves. As a result, the processing region is isolated from the outside, and chips do not scatter outside during processing.

Next, the operation of the above-described embodiment will be described. The Y-axis feed servomotors 14, 24 and the X-axis feed servomotors 34, 44 are synchronously controlled for each of the Y-axis and the X-axis by a pre-programmed numerical controller, and are detected by encoders incorporated in the respective servomotors. Feedback control is performed based on the current position feedback information of the corresponding first slider 4 and second slider 5. The Z-axis feed servomotor 54 is a spindle head 6 which is detected by an encoder incorporated in the Z-axis feed servomotor 54 by a pre-programmed numerical controller.
Is feedback-controlled based on the current position feedback information. Thus, the spindle head 6 can be positioned and controlled in the X-axis direction, the Y-axis direction, and the Z-axis direction, and the tool 80 attached to the lower part of the rotary tool spindle 101 on the spindle head 6
The workpiece 2 can be machined by three-dimensionally positioning a with respect to the workpiece 2.

When the X-axis feed servo motors 34 and 44 are driven leftward, the second slider 5
Propulsion acts on the protrusions 36 and 46 to the left via the nuts 35 and 45 and the nuts 35 and 45, and receives the frictional resistance from the guide rails 33 and 43 to the right. X-axis feed servo motor 3
Since the sliders 4 and 44 are driven synchronously, the inclination of the second slider is reduced. However, synchronization errors and guide rail 3
The second slider slightly turns due to the difference in the frictional resistance received from 3, 43. When the second slider 5 is moving rightward,
The power relationship is the opposite of when going left. Thereby, the second slider 5
Is turned in the opposite direction when positioned in the leftward direction and when moved and positioned in the rightward direction. Since the center of this rotation is between the guide rails 31 and 41 and the tool spindle 101 is near the center of this rotation, there is almost no positioning error in the left-right movement direction. As a result, in the round processing by contouring, it is possible to reduce a decrease in the shape accuracy of the workpiece caused by the switching of the quadrants of the XY coordinates. The propulsive force from the ball screws 33 and 43 acts on both sides of the center of the mass of the slide system including the second slider 5 and the tool spindle 101 mounted thereon. Therefore, when the second slider is accelerated or decelerated, the inertial force generated by the mass is transferred to the ball screw 3.
Since it is received almost equally at 3 and 43, no force for tilting the second slider is generated, and smooth acceleration and deceleration can be performed.

Next, the automatic tool change operation will be described.
As shown in FIG. 6, the opening 90 a of the fixed cover 90 is closed by the movable cover 91 during the processing step. When the machining process by the tool 80a is completed, the magazine plate 72 is rotated clockwise so that the empty tool holding portion 74a of the magazine plate 72 is aligned with the tool exchange position of the tool spindle 101 in the left-right direction (X direction). Rotate. At this position, the tool spindle 101 is retracted in the Y direction until the tool holding groove of the tool 80a fixed to the end face of the tool spindle 101 engages with the annular projection 75 of the tool holding portion 74a of the magazine plate 72. In this state, the draw bolt of the tool spindle 101 is released, the tool spindle 101 is further retracted in the Z direction, and completely separates from the tool shank. And
The magazine plate 72 is further rotated clockwise so that the next tool 80b to be used, which is held in the other tool holding groove 74b of the magazine plate 72, is aligned with the axis of the tool spindle 101. At that position, the tool spindle 101 is advanced in the Z direction, the shank of the tool 80b is fitted into the tool receiving hole at the tip thereof, and the tool 80b is moved to the tool spindle 1 with a draw bolt.
Fixed to 01. The spindle head 6 is a magazine plate 7
When the magazine plate 72 advances in the Y direction to a position where it does not interfere with the rotation of the magazine 2 (including the movable cover 91), the magazine plate 72 is rotated counterclockwise to return to the initial standby position. In this state, the opening 90a of the cover 90 of the tool changing device is completely closed by the movable cover 91, and thereafter, the processing by the tool 80b is performed.

[0019]

As described above, in the vertical machine tool according to the first aspect, the tool spindle moves up and down between a pair of guide rails that enable the second slider to move in the left-right direction.
In the vertical machine tool, the tool spindle moves vertically through the first slider and the second slider. The second slider is turned in the opposite direction when it is positioned in the leftward direction and when it is positioned in the rightward direction. Both the spindle head and the center of the rotation are between the guide rails. Therefore, there is almost no positioning error between the left and right (X-axis direction) of the spindle head.

Further, when a reaction force of the thrust force due to the cutting is applied in a direction for causing the spindle head to float upward,
The reaction force is substantially evenly distributed to the pair of guide rails that enable the second slider to move in the left-right direction, the guide rails are hardly deformed, and the deformation is not enlarged at the position of the spindle head. Further, since the rigidity between the workpiece and the spindle head is high, there is an advantage that vibration during cutting is reduced, the shape accuracy and surface roughness of the machined surface are good, and the tool life can be extended. In addition, the mass of the slide system including the second slider and the tool spindle mounted on the second slider is substantially evenly distributed to the pair of guide rails that enable the second slider to move in the left-right direction. It becomes uniform, there is little deterioration in positioning accuracy, and good processing accuracy can be maintained over a long period of time.

According to the third aspect of the present invention, a movable cover that can rotate integrally with the tool magazine device and closes an open portion of the cover device when the tool magazine device is at the rest position is attached to the magazine device. The opening and closing time of the movable cover is omitted, so that the structure can be simplified and the tool replacement time can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a vertical processing machine having a feed unit configuration and a magazine cover according to the present invention.

FIG. 2 is a right side view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a partially exploded perspective view showing a unit configuration of the present invention.

FIG. 6 is a sectional view taken along line CC of FIG. 2;

FIG. 7 is a partial schematic perspective view of the tool magazine device of the present invention.

FIG. 8 is a partial view seen from D in FIG. 7;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bed, 2 ... Jig apparatus, 3 ... Workpiece, 4 ... 1st slider, 5 ... 2nd slider, 6 ... Spindle head, 7 ... Tool magazine Device 8 ... plate 9 ... vertical feed unit device 10 ... horizontal feed unit device 72 ...
-Magazine plate, 101 ... Tool spindle.

Claims (3)

[Claims] 1. A first slider provided on a bed and movable in a first horizontal direction, and a second slider laminated on the first slider and movable in a second horizontal direction perpendicular to the first direction. A tool spindle provided on the second slider and movable in the vertical direction, and a jig device provided below the guide rails of the first slider, the second slider, and the spindle head for positioning and clamping a workpiece, A vertical machine tool characterized in that the tool spindle moves vertically between a pair of guide rails that enable the second slider to move in the left-right direction. 2. A first slider provided on a bed and movable in a first horizontal direction, and a second slider laminated on the first slider and movable in a second horizontal direction perpendicular to the first direction. A spindle head provided on the second slider and movable vertically, and a jig device provided below the guide rails of the first slider, the second slider, and the spindle head for positioning and clamping a workpiece, A vertical machine tool characterized in that a tool spindle moves up and down through a first slider and a second slider. 3. A tool magazine device according to claim 1, further comprising a tool magazine device rotatable around an axis parallel to the axis of said spindle head, for exchanging tools with said spindle head. A cover device for isolating the tool magazine device from the processing area when the magazine device is in the rest position;
The cover device has an opening that allows the tool magazine device to rotate from a rest position to a tool attachment / detachment position cooperating with the spindle head, and closes the open portion of the cover device when the tool magazine device is at the rest position. A vertical machine tool, wherein a movable cover to be mounted is attached to the tool magazine device so as to be able to rotate integrally with the tool magazine device.