JP2000158213A - Tool fixing structure of machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized tool fixing structure for fitting a tool or the like to a machine tool, which can have sufficient stiffness, and which can easily remove the tool while it can fix the tool by light force. SOLUTION: A tool fixing structure of a machine tool comprises an inverted- trapezoidal ridge 5, an inverted-trapezoidal groove 31, a rock hole 11 piercing through this inverted-trapezoidal ridge 5 or one of both inclined surfaces of the inverted-trapezoidal groove 31, a lock piece 12 inserted in the lock hole so as to be axially movable, and a lock screw 23 incorporating a conical front end 22, the lock piece 12 including a saw tooth-like cutout 14 incorporated therein with an inclined lock surface 13 adapted to slide on one of the inclined surfaces of the inverted-trapezoidal groove or abut against an inclined surface of the inverted-trapezoidal ridge, and a conical hole 16 formed in the peripheral surface, for receiving the conical front end 22, the lock hole 11 and the lock screw 23 crossing each other so that the conical surface of the conical front end abut against the retracting side of the peripheral surface of the lock hole in the lock piece in order to urge the lock piece 12 in the retracting direction under wedging action when the lock screw 23 is tightened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing structure for fixing a tool or a tool holder (hereinafter, referred to as "tools") of a machine tool to a machine. The present invention relates to a structure for detachably fixing a head, a rotary tool holder, and the like to a machine.

[0002]

2. Description of the Related Art A turning tool of a lathe is fixed by inserting a shank of the cutting tool into a U-shaped groove provided on a tool stand and fastening the side face of the shank with a bolt. Therefore, the tool can be replaced by unfastening the bolt, but the replacement operation is not always easy. Therefore, the shank of the cutting tool and the tip (head) of the cutting tool to which the cutting edge (tip) is attached are divided to provide a head fixing structure on the shank side, and only the head can be replaced while the shank is fixed to the tool base. Various structures have been proposed.

A structure generally used as a structure for fixing the head is such that a deep groove such as a T-shaped groove or an inverted trapezoidal groove is provided in the head, while a clamp bar (pull bar) having a bulging portion at the tip of the shank. , A draw bar, etc.) and a pull bar retracting means, and the head is fixed by retracting the clamp bar with the tip of the clamp bar fitted in the groove of the head. As the retracting means of the clamp bar, for example, a disc spring, a hydraulic cylinder, a screw, a wedge, or the like is used. Serrations and keys are used for positioning the shank and the head during locking.

When a rotary tool (drill or the like) or a boring tool is attached to a machine, a tool holder on which the rotary tool or the boring tool is mounted is fixed to a shank fixed to a tool base with the above-described structure. That is also being done. Further, a tool holder for fixing a rotary tool or a boring tool is provided with a shank similar to a shank of a tool, and is directly fixed to a tool table.

[0005]

A high rigidity is required for a tool fixing structure of a machine tool. On the other hand, a wide variety of tools are mounted on the machine tool according to the processing shape of the workpiece, so that the tool can be changed quickly and easily in order to improve machining efficiency and reduce the work load. Required. Furthermore, the shape of the work that can be processed is limited by the interference between the work and the tools, so that the structure for fixing the tool must be as small as possible.

Accordingly, the present invention provides a fixing structure for fixing tools to a machine tool, which has sufficient rigidity, facilitates the work of attaching and detaching tools, can fix tools with a small force, and can be reduced in size. It is an object of the present invention to obtain a fixing structure for tools capable of performing such operations.

[0007]

According to a first aspect of the present invention, there is provided a tool fixing structure for a machine tool which is used for fixing a replaceable tool or a tool holder to a fixing table provided on the machine tool. In the fixing structure of the above, an inverted trapezoidal ridge 5;
An inverted trapezoidal groove 31 fitted into the inverted trapezoidal ridge, a lock hole 11 penetrating one of the inclined surfaces 5a, 31a of the inverted trapezoidal ridge or the inverted trapezoidal groove, and an axially movably inserted through the lock hole. Lock screw 12 having lock piece 12 and conical tip 22
And the lock piece 12 is provided with the one slope 5
a, a notch 14 having a locking slope 13 abutting against the surface of an inverted trapezoidal groove or an inverted trapezoidal ridge sliding on 31a, and a conical hole 1 provided on the peripheral surface for receiving the conical tip 22.
The lock hole 11 and the lock screw 23 are provided so as to intersect with each other, and when the lock screw 23 is screwed in, the conical surface at the tip of the cone contacts the retracted side of the conical peripheral surface of the conical hole of the lock piece. The lock piece 12 is urged in the retracting direction by a wedge action upon contact.

According to a second aspect of the present invention, in the fixing structure for a tool of a machine tool according to the first aspect, the groove depth S of the inverted trapezoidal groove 31 is greater than the height T of the inverted trapezoidal ridge 5 provided on the fixing stand. When the tool or the tool holder is fixed slightly deeper, the fixed base and the tool or the tool holder are in surface contact with each other at both sides of the inverted trapezoidal groove 31 and the inverted trapezoidal ridge 5 when the tool or the tool holder is fixed.

The invention described in claim 3 is the first or second invention.
In the fixing structure of the tool of the described machine tool,
A prismatic shank 3 fitted into a U-shaped cross-section groove of a tool stand of a machine tool, a receiving surface 6 protruding from one side surface and integrally formed, and a direction perpendicular to the longitudinal direction of the shank on the receiving surface. An inverted trapezoidal ridge 5 formed integrally is provided.

According to a fourth aspect of the present invention, in the fixing structure for a tool of a machine tool according to the first, second, or third aspect, the lock piece 12 is elastically urged by a spring to project the rotating ball 17 projecting from the lock slope 13. It is characterized by having.

[0011]

With the tools 1, 41, and 42, the lock screw 23 is inserted into the inverted trapezoidal groove 31 with the inverted trapezoidal ridge 5 of the fixed base fitted therein.
Is fixed by screwing. When the lock screw 23 is screwed in, the peripheral surface of the conical tip 22 comes into contact with the peripheral surface of the conical hole 16 of the lock piece, and the lock piece 12 is pulled in. At this time, a large draw-in force due to the wedge action between the conical peripheral surfaces acts on the lock piece 12, and since the conical peripheral surfaces are in contact with the projections and the holes, the contact surface pressure is small and the screwing force of the lock screw is efficiently reduced. It can be converted to the retraction force of the lock piece. A plurality of lock screws and conical holes may be provided in one lock piece.

When the lock piece 12 is retracted, the lock slope 13 provided on the lock piece presses one slope 31a of the inverted trapezoidal groove provided on the tools, thereby pulling the tools toward the fixed table, The other slope 31b of the trapezoidal groove is urged in a direction to press the slope 5b of the inverted trapezoidal ridge on the corresponding side. That is, when the lock piece 12 is retracted, the tools are locked on the lock slope 13 of the lock piece and the other slope 31 of the inverted trapezoidal groove.
b and the bottom of the inverted trapezoidal groove or the receiving plane 6 on both sides of the inverted trapezoidal groove are fixed to the fixed base in close contact. In a structure in which the groove depth S of the inverted trapezoidal groove is greater than the height T of the inverted trapezoidal ridge,
Since the flat surfaces on both sides of the inverted trapezoidal groove are fixed to the fixed base in close contact, and the width between the two fixed surfaces increases,
Tools can be fixed more stably.

A stopper plate 32 can be fixed to the tools so as to close one end of the inverted trapezoidal groove 31. When the inverted trapezoidal groove 31 is inserted into the inverted trapezoidal ridge 5, the stopper plate 32
, The position of the tools in the direction orthogonal to the inverted trapezoidal groove 31 (the height of the cutting edge) is defined. The stopper plate 32 can be provided so as to slightly protrude toward the fixed base side from the tools, so that the inclination of the tools at the position regulated by the stopper plate can be more reliably prevented.

Further, by screwing the lifting screw 38 to the stopper plate, the mounting height of tools can be adjusted. If two lifting screws 38 are provided, the inclination of tools at the time of height adjustment can be prevented. In order to prevent this inclination, it is desirable to make the interval between the two adjustment screws as wide as possible.

According to a third aspect of the present invention, there is provided a structure in which a prismatic shank 3 fitted into a U-shaped groove of a tool stand of a machine tool is used as a fixed base, and a receiving surface 6 protruding from a side surface of the fixed base is provided. Thus, the projecting portion of the stopper plate 32 can be brought into contact with the fixed base while avoiding interference with the tool base. This stopper plate can be used as a means for supplying cutting oil to the cutting edge by providing an oil hole 36 inside.

The rotating ball 17 provided on the lock slope 13 of the lock piece is used to smoothly insert and remove the reverse trapezoidal groove 31 of the tools into and from the inverted trapezoidal ridge 5 with the lock piece loosened. It is valid. Further, in the structure provided with the receiving surface 6, by providing the receiving surface wide in the longitudinal direction of the inverted trapezoidal ridge 5, it is possible to prevent galling due to the inclination of the tools during the insertion / removal operation, and to reduce the number of tools. Stable fixing can be realized.

By providing a loose spring 20 at the bottom of the lock hole 11 for urging the lock piece 12 in the pushing direction, the lock piece can be smoothly returned when the lock screw 23 is loosened, and when the lock screw is loosened. However, the direction of the lock slope is stable, and the work of inserting and removing tools becomes easy.

[0018]

Embodiments of the present invention will be described below with reference to the drawings showing examples. 1 and 2 show a first embodiment of the present invention. The tool 1 of the first embodiment is a cutting tool, and the fixing base 2 is a cutting tool holder provided with a shank 3 having the same shape as the shank of the cutting tool.
The shank 3 is fixed to the lathe by being inserted into a tool mounting groove having a U-shaped cross section provided on a tool rest or turret (tool rest) of the lathe. That is, the shank 3 of the fixed base 2 is fixed to the tool base of the machine tool instead of the cutting tool. A receiving plate 4 extending downward from the lower surface of the shank 3 is integrally formed on one side surface of the shank 3, and an inverted trapezoidal ridge 5 extending in a direction orthogonal to the longitudinal direction of the shank 3 is integrally formed at the center of the receiving plate 4. Is formed. The opposite sides of the inverted trapezoidal ridge 5 of the receiving plate are receiving surfaces 6 that abut against the side surfaces of the shank of the cutting tool. Oil supply holes 7, 7 are provided at the base end of the shank 3 of the fixed base, and the oil supply holes 7, 7 communicate with a long groove 8 opened in the receiving surface 6 (see FIG. 3).

The fixed base 2 is provided with a lock hole 11 penetrating one slope 5a of the inverted trapezoidal ridge 5, and a lock piece 12 is slidably fitted in the lock hole 12 in the hole axis direction. Has been inserted. The lock piece 12 is provided with a saw blade-shaped notch 14 having a lock slope 13 coplanar with the one slope 5a of the inverted trapezoidal ridge, and a notch 14 of a small diameter portion 15 on the base end side. Conical hole 16
(See FIG. 3). This lock piece 1
2 is provided with a horizontal hole opening in the lock slope 13 in a direction perpendicular to the axis thereof, a rotating ball 17 slightly projecting from the lock slope into the horizontal hole, a coil spring 18 for urging the rotary ball, and a horizontal hole. A blind screw 19 screwed into the hole and locking the coil spring 18 is provided. Rotating ball 1
7 is held by the urging force of the coil spring 18 so that a part of its peripheral surface protrudes from the lock slope 13 (see FIG. 3). The lock hole 11 is a stepped hole having a diameter that allows the large diameter portion and the small diameter portion of the lock piece 12 to be slidably fitted to each other.

The shank 3 of the fixed base is provided with a screw hole 21 from the tip end toward the lock hole 11, and a lock screw 23 having a conical tip 22 is screwed into the screw hole. The lock screw shown in FIG. 1 is a screw with a hexagonal hole, and the head 24 is screwed into the shank 3 while being buried in the large-diameter hole formed at the opening end of the screw hole 21. In this screwed state, the conical tip 22 of the lock screw is inserted into the conical hole 16 of the lock piece 12.

A pressing spring 20 for urging the lock piece 12 in the pushing direction is inserted into the bottom of the lock hole 11 (FIG. 1). When the lock screw 23 is loosened, the pressing spring pushes the lock piece 12 to press the side surface of the conical hole 16 against the conical tip 22 of the lock screw. By this pressing, the locking slope 13 is held parallel to the slope of the inverted trapezoidal ridge 5, and the movement of the inverted trapezoidal groove 31 when the cutting tool is inserted and removed is made smooth. Further, the pressing spring 20 has a function of pushing out the lock piece 12 from the lock hole 11 when the lock screw 23 is removed.

The cutting tool 1 is provided with an inverted trapezoidal groove 31 on the side surface of the shank to be fitted to the inverted trapezoidal ridge 5 of the fixed stand. A cutting blade 30 is fixed to the tip of the cutting tool 1, and a stopper plate 3 is provided on the upper surface so as to close the inverted trapezoidal groove 31.
2 is fixed by bolts 33. An oil hole 35 facing the long groove 8 of the fixing base is opened on the base end side of the side surface of the cutting tool 1 where the inverted trapezoidal groove 31 is provided, and the oil hole 35 opens on the upper surface of the base end of the cutting tool. Further, it passes through an oil hole 36 provided in the stopper plate 32 and opens at a portion immediately above the cutting edge of the stopper plate (see FIG. 1).

FIG. 2 shows a state in which the cutting tool 1 is mounted on the fixed base 2. The cutting tool 1 is inserted into the inverted trapezoidal groove 31 into the inverted trapezoidal ridge 5 until the stopper plate 32 comes into contact with the upper end of the receiving plate 4 of the fixing stand, and then the lock screw 23 is screwed in so that the conical tip 22 of the lock screw is locked. 12, the locking slope 13 of the lock piece is turned into the inverted trapezoidal groove 3 by the pulling operation.
1 is fixed to the fixed base 2 by pressing one slope 31a. The depth S of the inverted trapezoidal groove is slightly deeper than the height T of the inverted trapezoidal ridge, and therefore, in a fixed state, the surfaces 34 on both sides of the inverted trapezoidal groove of the cutting tool and the other side of the inverted trapezoidal groove (the lock piece is provided). The slope 31b (opposite to the side) is in close contact with the fixed receiving surface 6 and the other slope 5b on the other side of the inverted trapezoidal ridge, and one slope 5a of the inverted trapezoidal groove is in close contact with the lock slope 13 of the lock piece. It is fixed to the fixed base 2. In this state, when the cutting oil is supplied from the oil supply hole 7 opened in the shank of the fixed base, the cutting oil is cut through the long groove 8, the oil hole 35 provided in the shank of the cutting tool, and the oil hole 36 provided in the stopper plate. It is supplied to the blade 30.

According to the fixing structure of the present invention, the tool (tools) 1 can be strongly fixed by fastening the lock screw with a small force. Therefore, it is possible to fasten and release the tools 1 by manually gripping and turning the knob 37 using a lock screw having a knob 37 as shown in FIG. 3). Although the structure using the lock screw with the knob 37 is convenient for attaching and detaching the tools 1, the knob 37 may interfere with the work and hinder the processing operation. Use a lock screw with no protruding head as shown.

FIGS. 4, 5 and 6 show modifications of the fixed base 2 of FIG. 4 has the height of the receiving plate 4 equal to the height of the shank 3, and a straight lock piece 12 is fitted into a lock hole 11 thereof. FIG. 5 shows an example in which the lock hole 11 is provided in such a size that one slope 5a of the inverted trapezoidal ridge 5 is removed, and the slope of the inverted trapezoidal ridge 5 on the lock hole side is a lock piece. The lock slope 13 is formed only. In the example of FIG. 6, the receiving plate 4 is extended in the vertical direction of the shank 3 to form a long inverted trapezoidal ridge 5.
By increasing the length, the stability at the time of mounting tools and the smoothness at the time of loading and unloading are improved.

FIG. 7 shows a state in which a lifting screw 38 is screwed onto the stopper plate 32, and the lifting screw is provided at a position where the tip thereof contacts the upper surface of the receiving plate 4. Byte 1 to fixed base 2
Then, the height of the cutting edge 30 of the cutting tool with respect to the fixed base 2 can be adjusted by adjusting the lifting screw 38. The stopper plate 32 is, as shown in FIG.
The inverted trapezoidal groove 31 can be attached to the end face on the side opposite to FIG.

FIG. 9 shows a tool holder interposed between the fixed base and the shank of the tool. A U-shaped groove 46 extending in a direction perpendicular to the inverted trapezoidal groove is provided on a side surface of the bite holder opposite to the inverted trapezoidal groove 31. The tool and the tool holder are integrated by fitting the tool shank into the U-shaped groove and fastening with the fastening bolts 47. The height of the cutting edge of the cutting tool is adjusted by operating a lifting bolt of the stopper plate 32 fixed to the upper surface of the cutting tool holder. By using such a tool holder, a normal tool can be fixed to the fixing base 2 so that the height can be adjusted.

FIG. 10 shows a modification of the shank of the fixed base. The tool mounting groove of the U-shaped cross section provided on the turret is usually 25 mm square, but some turrets have a tool mounting groove of 50 mm width. At this time, by using a shank having a wide width as shown in FIG. 10, the cutting tool can be fixed to the turret of the machine tool so that the cutting edge height can be adjusted.

The fixing structure according to the present invention can also be used as a structure of a portion for attaching a boring tool 41 shown in FIG. 11 or a rotary tool holder 42 shown in FIG. 12 to a machine tool. The structure shown in FIG. 11 is an example in which a tool holder 43 in which a boring tool 41 is mounted on a fixed base 2 provided with a shank 3 similar to the shank of FIG. An inverted trapezoidal ridge 5 and an inverted trapezoidal groove 31 shown in FIG. Lock holes, lock pieces, and the like are provided in the same manner as the structure shown in FIG. 1, and the head of the lock screw 23 faces the base end of the shank 3.
It is also possible to reverse the positional relationship between the inverted trapezoidal ridge 5 and the inverted trapezoidal groove 31. That is, the inverted trapezoidal ridge 5 on the tool 1 side,
The lock piece 12 and the lock screw 23 are provided, and an inverted trapezoidal groove 31 is provided on the fixed base 2 side.

In the example shown in FIG. 12, an inverted trapezoidal ridge 5 is integrally provided on a fixed base 2 which is fixed to a tool base of a machine tool by a bolt (not shown), and a holder block 44 holding a rotary tool holder 42 is provided. This is an example in which an inverted trapezoidal groove 31 is provided, and the fixed base 2 and the holder block 44 are fixed with the same structure as shown in FIG. In FIG. 12, two lock pieces 12 are provided at intervals in the longitudinal direction of the inverted trapezoidal ridge 5, and lock screws 23 for each of them are shown.

As shown in FIG. 13, in a structure in which an inverted trapezoidal ridge 5 is provided on the fixed base 2 side and an inverted trapezoidal groove 31 is provided on the tools 1, 43, 44 side, an inverted trapezoidal shape is provided on the tools side. Groove 31
, A lock hole 11, a lock piece 12, and a lock screw 23 can be provided. In addition, it is also possible to provide a structure in which an inverted trapezoidal groove is provided on the fixed base side and an inverted trapezoidal ridge is provided on the tools side, and a lock hole, a lock piece and a lock screw penetrating the inverted trapezoidal ridge on the tools side can be provided, Still further, in a structure in which an inverted trapezoidal groove is provided on the fixed base side and an inverted trapezoidal ridge is provided on the tool side, a lock hole, a lock piece and a lock screw penetrating the inverted trapezoidal groove can be provided on the fixed base side.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a first embodiment.

FIG. 2 is a perspective view showing an assembled state of the first embodiment.

FIG. 3 is a plan view showing a lock screw with a knob and a fixing base.

FIG. 4 is a perspective view showing a first modification of the fixed base.

FIG. 5 is a perspective view showing a second modification of the fixed base.

FIG. 6 is a perspective view showing a third modification of the fixed base.

FIG. 7 is a perspective view showing a fixing structure capable of adjusting the height.

FIG. 8 is a perspective view showing another mounting structure of the stopper plate.

FIG. 9 is a perspective view of a normal tool holder.

FIG. 10 is a perspective view showing a modification of the shank of the fixing base.

FIG. 11 is a perspective view showing a fixing structure of a boring tool;

FIG. 12 is a perspective view showing a structure for fixing a holder of a rotary tool.

FIG. 13 is a plan view showing a modification of the fixed base and tools.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool 2 Fixing stand 5 Inverted trapezoid ridge 5a One slope 6 Receiving plane 11 Lock hole 12 Lock piece 13 Lock slope 14 Notch 16 Conical hole 17 Rotating ball 22 Conical tip 23 Lock screw 31 Inverted trapezoidal groove 31a One slope 38 Screw 42 Tool holder 44 Holder block S Depth of inverted trapezoidal groove T Height of inverted trapezoidal ridge

Claims (4)

[Claims] An inverted trapezoidal ridge (5) and a reverse trapezoidal ridge (5) for fixing a tool or a tool holder of a machine tool used for fixing a replaceable tool or tool holder to a fixing table provided on the machine tool side. An inverted trapezoidal groove (31) to be inserted into a lock hole (11) penetrating one slope (5a, 31a) of the inverted trapezoidal ridge or the inverted trapezoidal groove.
A lock piece (12) inserted in the lock hole movably in the axial direction, and a lock screw (23) having a conical tip (22), and the lock piece (12) is provided on the one slope ( 5a, 31a), a saw blade-shaped notch (14) provided with a locking slope (13) abutting against the surface of an inverted trapezoidal groove or an inverted trapezoidal ridge, and the conical tip (22 The lock hole (11) and the lock screw (23) are provided so as to intersect with each other, and when the lock screw (23) is screwed in, the conical surface at the tip of the cone is locked. A fixing structure for a tool of a machine tool, wherein a lock piece (12) is urged in a retraction direction by a wedge action by abutting against a retraction side of a conical peripheral surface of a conical hole of a piece. 2. When the depth of the inverted trapezoidal groove (31) is slightly deeper than the height (T) of the inverted trapezoidal ridge (5) provided on the fixed base, and the tool or tool holder is fixed. 2. A tool fixing structure for a machine tool according to claim 1, wherein the fixed base and the tool or the tool holder are in surface contact with each other on both sides of the inverted trapezoidal groove (31) and the inverted trapezoidal ridge (5). . 3. A fixed shank having a prismatic shank (3) fitted into a U-shaped groove of a tool stand of a machine tool, and a receiving surface (6) integrally formed by protruding from one side surface thereof. 3. The fixing structure for a tool of a machine tool according to claim 1, further comprising an inverted trapezoidal ridge integrally formed on the receiving plane in a direction orthogonal to a longitudinal direction of the shank. 4. The lock piece (12) according to claim 1, wherein the lock piece (12) is provided with a rotating ball (17) which is elastically urged by a spring and protrudes from the lock slope (13). Fixing structure for machine tool tools.