JPH032605B2 - - Google Patents

Description

Detailed Description of the Invention A. Object of the Invention (1) Industrial Field of Application The present invention provides a structure in which a leaning tower type turret head rotatably supports a plurality of tool rotation spindles and is rotatably supported with respect to a frame. When one of the spindles is positioned at the machining position as the turret head rotates, at least one of the other spindles is at the tool change position. This invention relates to a tool holder release device used in a drive unit.

(2) Prior art A leaning tower type turret head that rotatably supports a plurality of tool rotation spindles is rotatably supported on a frame body, and while one of the plurality of spindles is in a processing position, the other spindle is rotated. A machine tool equipped with a tool drive unit configured such that at least one of its spindles is in a tool changing position is disclosed in Japanese Patent Application Laid-Open No.
This is known from the prior art as seen in Japanese Patent No. 122976.

(3) Problems to be solved by the invention If the structure of the tool drive unit is made compact in order to increase the mechanical rigidity of the tool drive unit and improve machining accuracy, the proximal ends of the plurality of spindles supported by the turret head will be reduced. The parts become close to each other. At the tip of the spindle, the tool holder engages with the tip of a drawbar that axially passes through the hollow part of the spindle. When the drawbar is pushed by the push rod to move the drawbar toward the tip side of the spindle against the spring biasing force, the engagement relationship between the drawbar and the tool holder is released, and the tool holder can be removed from the tip of the spindle. can. If the push rod for pressing the base end surface of the drawbar is set at a fixed position, the base end of the spindle and the push rod may interfere with each other as the turret head turns when the tool drive unit is made more compact. Put it away.

In addition, the spindle receives an axial force due to the push rod's pressing force on the drawbar, which applies an axial force to the bearing that rotatably supports the spindle relative to the turret head, which has an undesirable effect on the bearing. .

Therefore, even if the structure of the tool drive unit is made compact, the present invention prevents interference between the base end of the spindle and the push rod as the turret head rotates, and prevents the pressing force of the push rod from exerting excessive force on the spindle bearing. The main purpose of this invention is to obtain a tool holder release device for a machine tool that does not cause any adverse effects.

B. Structure of the Invention (1) Means for Solving Problems According to the present invention, a leaning tower type turret head that rotatably supports a plurality of tool rotation spindles is rotatably supported on a frame. The tool drive unit of the machine tool is such that when any one of the spindles is positioned at the machining position as the turret head rotates, at least one of the other spindles is at the tool change position. The tool holder release device is used in a tool holder detachment device, the base end of which is pivotally supported by the frame, and which moves the spindle positioned at the processing position to the tool exchange position in conjunction with a clutch for connecting it to the drive source side. a hook that swings between an engagement position where it engages with the positioned base end of the spindle and a retracted position where it is spaced apart from the base end of the spindle at the tool exchange position; When the hook is in the engaged position, the hook is held on the distal end side of the drawbar by pressing the base end surface of the drawbar that axially passes through the hollow part of the spindle in the tool exchange position. There is provided a tool holder release device for a machine tool, comprising: a push rod for releasing a tool holder in the tool exchange position from the spindle at the tool exchange position.

(2) Operation When the turret head rotates, the hook is placed in a retracted position away from the base end of the spindle. When the spindle subject to tool exchange is positioned at the tool exchange position, the hook swings and engages with the base end of the spindle at the tool exchange position, and the push rod moves forward and presses the base end surface of the drawbar. . As a result, the drawbar moves toward the distal end with respect to the spindle, so that the tool holder can be removed from the spindle. During this time, since the hook is engaged with the base end of the spindle, the spindle does not move in the axial direction and no undue force is applied to the bearing supporting the spindle.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. First, in FIGS. 1 and 2, a horizontal moving table 3 is mounted on the machine tool bed 1 and is moved horizontally by a feed motor 2. motor 4
A back-and-forth moving table 7 is mounted which is moved back and forth along a pair of guide rails 5 and 6. A column 8 is erected on this back-and-forth direction movable table 7, and a tool drive unit A is moved up and down by a feed screw 10 which is rotationally driven by a feed motor 9.
The lifting frame 11 has a pair of left and right guide rails 12, 1 extending vertically on the front side of the column.
3 relative to the column 8.
A leaning tower type turret head 17 is supported on the front side of the lifting frame 11 and is pivoted around an axis in a direction inclined with respect to the front-rear direction in a horizontal plane. 66 is formed. The center axis of each spindle head 16, 66 is set at the first axis in order to avoid mutual interference of the internal mechanisms of the tool drive unit A.
They are in a twisted relationship with each other as shown in the figure.
As shown in FIG. 2, when the tool is in cutting operation, the center axis of the spindle head is directed in the longitudinal direction with respect to the column 8, and when changing the tool, as the turret head 17 rotates, the center axis of the spindle head is Head left and right with respect to column 8. In Figure 2, spindle head 1
6 is in the cutting position, and the spindle head 66 is in the tool changing position. Also, as shown in Figure 2,
The guide rail 13 is arranged in front of the guide rail 12, and the distances from each guide rail 12, 13 to the turret head 17 are both short.

In FIG. 3, the cylindrical support part 1 of the lifting frame 11 is
The outer circumferential side of the cylindrical connecting portion 18 of the turret head 17 is rotatably supported on the inner circumferential side of the turret head 17 via a bearing 15, and the outer circumferential flange 11f of the lifting frame 11 and the outer circumferential flange 17f of the turret head 17 are supported on the inner circumferential side of the turret head 17. The opposing surfaces are configured to be able to come into sliding contact with each other. and each outer periphery flange 11
The back sides of f and 17f are tapered surfaces 11t and 17f, respectively.
17t, and the outer surfaces of the pair of outer circumferential flanges 11f, 17f are surrounded by an annular clamp 19 for restraining the rotation of the turret head 17 as required.

A gear 20 is integrally fixed to the end surface side of the cylindrical connecting portion 18, and a turret rotation motor 21 mounted on the elevating frame 11 is attached to the gear 20. The bevel gear 23 and the gear 28 at the other end of the gear shaft 26 which is rotatably driven via the bevel gear 27 at one end of the gear shaft 26 which is pivotally supported on the cylindrical support part 14 by bearings 24 and 25 mesh with each other. It's on.

The rotational driving force of the tool rotation motor 29 mounted on the lifting frame 11 is transmitted through the output shaft 30 and the lifting frame 11.
A gear 34 on a gear shaft 33 rotatably supported by the elevator frame 11 via bearings 31 and 32, a gear 38 on a gear shaft 37 rotatably supported by the elevator frame 11 via bearings 35 and 36, and an elevator. The signal is transmitted to the spline 43 on the outer peripheral surface of the forward projection of the gear shaft 41 via the gear 42 on the gear shaft 41 which is rotatably supported by the frame 11 via bearings 39 and 40.

The spline 43 is engaged with a spline on the inner circumferential surface of the drive-side engaging member 44a of the clutch 44. The drive-side engagement member 44a has a cylindrical shape as a whole, and has an engagement portion on its front edge that engages with the driven-side engagement member 44b, and has an engagement portion on its outer peripheral surface near the rear end. A clutch operation wheel 45 having an annular groove 46 formed on the outer peripheral surface thereof is fixed.

A proximal end of a rod 47 that protrudes forward in parallel with the spline 43 is fixed to the lifting frame 11, and a fixed spindle 48 formed at the center of the rod 47 has a clutch operating cylinder 4.
9 is fitted. Both end walls of the clutch operating cylinder 49 are slidable along the outer peripheral surface of the rod 47, and a clutch operating pawl 50 fixed on the outer peripheral surface near the rear end of the clutch operating cylinder 49 is fitted into an annular groove of the clutch operating wheel 45. 46. Fourth
As shown in the figure, the base end of a sliding member 73 that protrudes in a direction perpendicular to the axial direction of the clutch operation cylinder 49 is fixed on the upper surface of the rear end of the clutch operation cylinder 49. The sliding member 73 is slidably fitted into a guide rail 74 parallel to a rod 47 whose base end is fixed on the elevating frame 11 and a stopper nut 75 is screwed into the distal end. The sliding member 7 along this guide rail 74
3 (FIG. 4), the clutch operating cylinder 49 slides along the rod 47 while always maintaining a constant orientation. When the pressure fluid is conducted to the pressure fluid path 51 in the rod 47, the clutch operation cylinder 49 is moved back and the clutch 44 is closed.
When the lever is in the disengaged state and pressure fluid is introduced into the pressure fluid path 52 in the rod 47, the clutch operation cylinder 49 moves forward and the clutch 44 becomes in the engaged state.

In FIG. 3, a hollow spindle 55 is rotatably supported on the inner circumference 17 of the spindle head 16 via a bearing 53 and a bearing group 54, and a clutch is mounted on the outer circumferential surface of the rear end of the hollow spindle 55. An annular driven-side engagement member 44b constituting 44
is fixed. Therefore, when the clutch 44 is in the engaged state, the rotational driving force on the spline 43 side is transmitted to the hollow spindle 55 via the clutch 44.

A tapered surface 55t that expands toward the front is formed on the inner peripheral surface side of the front end of the hollow spindle 55, and a tool holder 57 is formed on this tapered surface 55t.
A tapered surface 57t formed on the outer periphery of the plate is in close contact with the tapered surface 57t. The tool holder 57 has a tapered surface 5
In the state in which the hollow spindle 55 is fitted into the 5t section, the rotational driving force of the hollow spindle 55 is applied to the engagement pin 56 fixed to the front end surface of the hollow spindle 55 and the engagement pin 56 formed on the outer peripheral surface of the front end of the tool holder 57. By engaging with the recessed portion, the force is transmitted to the tool holder 57 via the engagement pin 56.

A tool holder shaft 58 having an enlarged portion at the rear end protrudes rearward from the rear end surface of the tool holder 57, and this tool holder shaft 58 extends in the axial direction within the hollow portion of the hollow spindle 55. It is adapted to fit into a cylindrical portion 60 formed at the front end of the drawbar 59. The cylindrical portion 60 has a plurality of, for example, three, radially penetrating ball holding holes formed at intervals in the circumferential direction, and the balls 61 are held in each ball holding hole so that they do not come off. has been done. A cylindrical member 62 having a tapered surface that expands forward is held at a position corresponding to the cylindrical portion 60 in the hollow portion of the hollow spindle 55 on the inner peripheral portion of the front end side. A nut 63 is screwed to the rear end of the drawbar, and the spring biasing force of a large number of annular leaf springs 64 interposed between the nut 63 and the shoulder on the inner peripheral side of the hollow spindle 55 causes The drawbar 59 is constantly receiving a backward tensile force, and due to this spring biasing force, each ball 61 moves along the tapered surface on the inner circumferential side of the cylindrical member 62, tightens the tool holder shaft 58, and tightens the tool holder 57. is securely held within the tapered surface 55t.

When removing the tool holder 57 from the hollow spindle 55, the turret head 17 is rotated to position the spindle head 16 at the tool exchange position, and then the base end surface of the draw bar 59 is pressed against the spring biasing force by a push rod described later. At the same time, the tool holder 57 is attached to the hollow spindle by engaging the gripping claw with the annular engagement groove 65 formed on the outer circumferential surface of the tip end of the tool holder 57 and pulling the tool holder 57 out of the hollow spindle 55. It can be removed from 55.

A pressurized air introduction hole 59c is formed in the drawbar 59 so as to penetrate in the axial direction, and when the tool holder 57 is removed from the hollow spindle 55 during tool exchange, pressurized air can be introduced into the pressure air introduction hole 59c. The pressurized air is transferred to the tapered surface 55.
The tapered surface 55t can be cleaned by spraying toward the t side.

In Figures 4 to 7, spindle head 1
6 is a machining position, and the tool 124, whose tool shaft 125 is held by the tool holder 57, is in a cutting operation state. In contrast, the spindle head 66 is in the tool change position. This spindle head 66
A hollow spindle 69 is rotatably supported on the inner peripheral side of the tool via a bearing 67 and a bearing group 68, and the hollow spindle 69 holds a tool holder 71 that holds a tool shaft 70.

The hollow spindle 69 has exactly the same structure as the hollow spindle 55, and the driven side engagement member 72 of the clutch 44 is fixed on the outer peripheral surface of the proximal end of the hollow spindle 69. An engagement groove 83 is formed adjacent to the engagement member 72. On the other hand, a bracket 79 protruding from the proximal end of the hook 80 is pivotally supported by a pivot portion 78 of a bracket 77 fixed to the elevating frame 11.
A forked engagement claw 82 that engages with the engagement groove 83 of the hollow spindle 69 is formed at the distal end of the hook 80, and a forked engagement claw 82 that engages with the engagement groove 83 of the hollow spindle 69 is formed at the center of the hook 80. A long hole 81 that is elongated toward
An engaging pin 76 protruding from the upper surface of the outer peripheral portion of the clutch operation cylinder 49 is loosely fitted into the elongated hole 81 . Therefore, while the clutch operating cylinder 49 is retracted and the clutch 44 is placed in the disengaged state when the turret head 17 is rotated by the operation of the turret rotation motor 21, the hook 80 is rotated about the pivot portion 78. The engaging claw 82 swings toward the lifting frame 11 and engages the engaging groove 8.
3, one of the pair of spindle heads, e.g., spindle head 16, is positioned at the machining position, and at the same time, the other spindle head, e.g., spindle head 66, is positioned at the tool changing position, and the clutch operating cylinder 49 is When the clutch 44 moves forward and becomes engaged, the hook 80 swings forward about the pivot portion 78, and the engagement pawl 82 engages the engagement groove 83, causing the hook 80 to move in the axial direction of the hollow spindle 69. To counter such forces,
To prevent excessive force from being applied to the bearing 67 and the bearing group 68. Particularly, as shown in FIGS. 6 and 7, a cylinder 90 is integrally formed within the hook 80, and a piston slides in this cylinder 90. The tip of the push rod 92, which is integral with the piston rod 91, can protrude toward the tip of the hook 80.
A flow path 93 is formed in the push rod 92, and when pressure fluid is introduced into the port 95 as shown in FIG. However, as shown in FIG.
When pressure fluid is introduced into the port 94 while engaged with the proximal end of the piston 91, the piston 91 moves toward the distal end of the hook 80, and the push rod 92 presses the proximal end surface of the drawbar 97.
The drawbar 97 is moved toward the tip of the spindle 69 against the spring force of the leaf spring 98. At the same time, the flow path 93 communicates with the port 96, and pressurized air passes through the port 96, the flow path 93, and the pressure air introduction hole 97c formed by the hollow part of the drawbar 97, and connects to the tapered surface 69t at the tip of the spindle 69. It is introduced into the annular gap between the tool holder 71 and the tapered surface 71t.

As a result, the engagement between the drawbar 97 and the tool holder 71 is released, and the tool holder 71 can be detached from the spindle 69.
The tapered surface 69t of is cleaned by pressurized air.
During this time, since the hook 80 is engaged with the base end of the spindle 69, the spindle 69 is not pressed toward the distal end, and no unreasonable force is applied to the bearings 67, 68.

C. Effects of the Invention As described above, according to the present invention, the hook swings in conjunction with the clutch for connecting the spindle positioned at the processing position to the drive source side, so the drive source of the hook operates the clutch. The hook can be operated in conjunction with the clutch, and the hook can be operated in conjunction with the clutch. Further, since the push rod is configured to be operated by a cylinder integrally constructed with the hook, when the turret head rotates, it is retracted to the retracted position together with the hook, so that it cannot interfere with the base end of the spindle. Furthermore, when changing tools, the hook engages with the base end of the spindle, so the spindle does not move toward the tip due to the pushing force of the push rod, and undue force is not applied to the bearing that supports the spindle. I won't join.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of a machine tool equipped with a support device for a tool drive unit according to an embodiment of the present invention, FIG. 2 is a plan view of the machine tool shown in FIG. 1, and FIG. Fig. 4 is a plan sectional view of the main part taken along the - line in Fig. 1, Fig. 5 is a plan sectional view of the main part taken along the - line in Fig. 4. 6 is a sectional view of the main part shown in FIG. 4, and FIG. 7 is a sectional view of the main part similar to FIG. 6 in an operating state different from that in FIG. 6. A... Tool drive unit, 11... Frame, 17... Turret head, 44... Clutch, 55, 69... Spindle, 71... Tool holder, 80... Hook, 9
0...Cylinder, 92...Push rod, 97...Draw bar.

Claims (1)

[Claims] 1. A leaning tower type turret head 17 that rotatably supports a plurality of tool rotation spindles 55, 69 is rotatably supported on the frame 11, and as the turret head 17 rotates, the spindles 55, 69 rotate. When one of the spindles 55 is positioned at the processing position, at least one spindle 69 of the other spindles
is a tool holder release device used in a tool drive unit A of a type of machine tool in a tool exchange position, the base end side of which is pivotally supported by the frame 11;
In conjunction with the clutch 44 for connecting the spindle 55 positioned at the processing position to the drive source side,
Spindle 6 positioned at the tool exchange position
a hook 80 that swings between an engagement position where it engages with the base end of the spindle 69 and a retracted position where it is spaced apart from the base end of the spindle 69 at the tool exchange position; when the hook 80 is in the engaged position,
By pressing the proximal end surface of a draw bar 97 that axially passes through the hollow portion of the spindle 69 at the tool exchange position, the tool holder 71 held on the distal end side of the draw bar 97 is moved to the spindle at the tool exchange position. A tool holder release device for a machine tool, comprising: a push rod 92 for release from a tool holder 69;