JP4961851B2 - Grinding wheel attachment / detachment structure - Google Patents

Description

  The present invention relates to a grinding wheel attachment / detachment structure, and more particularly, to a grinding wheel attachment / detachment structure suitable for automatic tool change.

  As a holding mechanism for a grinding wheel shaft of a grinding wheel used in a grinding machine or the like, there is a mechanism in which a grinding wheel having a tapered hole is fitted to a grinding wheel shaft that rotationally drives the grinding wheel and is fixed by a tightening nut (for example, Patent Document 1). According to this configuration, a simple configuration such as a tightening nut can be fitted into the grindstone shaft in close contact with the tapered hole, and the runout of the grindstone outer periphery when the grinding wheel is rotated by the grindstone shaft can be reduced. There is no need to waste an expensive grinding wheel layer for correction.

There is also a grinding wheel in which a grinding wheel sleeve holding a grinding wheel is provided with a tapered hole that fits with a grinding wheel shaft, and a pull stud located at the center of the tapered hole (for example, Patent Document 2). According to this configuration, by pulling the pull stud with the draw bar attached to the grindstone shaft side, the grindstone sleeve and the grindstone shaft are closely fitted in the tapered hole, and the pushing force is given to the pull stud by the drawbar, so that the grindstone is The contact between the sleeve and the grinding wheel shaft is released, and the grinding wheel can be attached and detached. Therefore, it is applicable also to the exchange of the grinding wheel by the automatic tool changer.
JP 61-182767 A Japanese Utility Model Publication No. 61-137457

  However, according to the grinding wheel disclosed in Patent Document 1, it takes time to attach and detach the grinding wheel to and from the grinding wheel shaft, and the search operation time cannot be shortened. In addition, since the grinding wheel is fixed to the grinding wheel shaft with a screw or the like, it is difficult to apply the grinding wheel to an automatic tool changer.

  Further, according to the grinding wheel disclosed in Patent Document 2, since the grinding wheel and the grinding wheel shaft are fitted only at the tapered portion, the axial displacement caused by the pulling force by the pull stud, There is a problem that the taper portion expands due to the centrifugal force accompanying rotation and axial displacement occurs, causing biting. In particular, when a grinding wheel is driven by high-speed rotation for grinding, a serious problem arises.

  Accordingly, an object of the present invention is to provide a grinding wheel attachment / detachment structure that can be applied to grinding wheel replacement by an automatic tool changer and that is difficult to displace the grinding wheel in the axial direction.

[1] According to the embodiment of the present invention, a grindstone wheel that holds a grindstone on the outer peripheral portion, has an opening on the first end face side, and has a tapered hole portion that leads to the opening on the second end face side. A pressing plate for contacting the first end surface of the grindstone wheel with a predetermined outer diameter and inner diameter and applying a pressing force to the second end surface of the grindstone wheel, and the grindstone wheel A grindstone shaft having a tapered portion inserted into the tapered hole portion, and a stepped portion that is formed in a step shape with respect to the tapered portion and contacts the second end surface side of the grindstone wheel with the predetermined outer diameter. And a clamp unit that can be fitted into a guide hole formed in the center portion of the grindstone shaft and that can clamp the pullstat fixed to the pressing plate, and the clamp unit includes the clamp wheel. Second An axial tensile force is applied to the pressing plate so that a predetermined contact pressure is generated between the end surface side and the step portion of the grindstone shaft, and between the tapered hole portion and the tapered portion, and the grindstone The grindstone that the wheel holds on the outer peripheral portion is positioned within the axial width of the tapered hole formed in the grindstone wheel, and the pressing plate is arranged on the second end face side of the grindstone wheel. Provided is a grinding wheel attaching / detaching structure characterized by being substantially the same as the diameter of a contact surface with which an end face is in contact .

  [2] The grindstone wheel is restrained by two surfaces, a tapered hole portion that fits into the grindstone shaft and a contact surface where the end surface of the grindstone shaft contacts the second end surface side of the grindstone wheel. The grinding wheel attaching / detaching structure described in [1] may be used.

[ 3 ] The clamp unit is configured to apply a pulling force or an pushing force to a pull stud provided on the grinding wheel side through a collet chuck by a draw bar provided on the grinding wheel shaft. The grinding wheel attaching / detaching structure described in [1] may be used.

  ADVANTAGE OF THE INVENTION According to this invention, it can apply to the replacement | exchange of the grinding wheel by an automatic tool change apparatus, and the attachment / detachment structure of the grinding wheel of a structure with which a grinding wheel cannot be displaced to an axial direction can be provided.

  FIG. 1 shows the structure of a grinding wheel according to an embodiment of the present invention. FIG. 1 (a) shows a grinding wheel 600 assembled by a grinding wheel 610, a pressing plate 620, and a pull stud 630, and FIG. These are the right view of the press plate 620, (c) is a figure which shows the left view of the grindstone wheel 610. The grinding wheel 600 includes a grinding wheel 610, a pressing plate 620, and a pull stud 630.

  The grindstone wheel 610 is formed by fixing a layer of the grindstone 611 so as to rotate together with the grindstone wheel 610 on the outer periphery of the cylinder. The grindstone wheel 610 is formed with a first end surface 610a perpendicular to the central axis CL and a second end surface 610b on the opposite side. A tapered hole portion 610c is formed at a predetermined taper angle coaxially with the central axis CL. Further, a key-like engaging portion 610d is formed in a part of the inner diameter region where the tapered hole portion 610c is not formed.

  The pressing plate 620 includes a key-like engaging portion 620a for engaging and fastening with a key-like engaging portion 610d of the grindstone wheel 610 coaxially with the central axis CL, and a first of the grindstone wheel 610 perpendicular to the central axis CL. 1 has an abutting portion 620b that abuts against one end surface 610a. The pressing plate 620 is twisted by a predetermined angle by inserting the key-like engaging portion 620a shown in FIG. 1B into the key-like engaging portion 610d of the grindstone wheel 610 shown in FIG. 1C. Thus, the abutting portion 620b is assembled in a state where it abuts on the first end surface 610a of the grindstone wheel 610. A screw hole 620 c is formed on the central axis CL of the pressing plate 620. The outer diameter or inner diameter of the contact portion 620b is preferably substantially the same as the outer diameter or inner diameter of the second end surface 610b formed on the grindstone wheel 610. That is, the outer diameters or inner diameters of the contact portion 620b and the second end surface 610b are approximate to each other so that the force from the pressing plate 620 is transmitted to the inside of the grinding wheel 610 and works efficiently on the second end surface 610b. It is preferable that the value be

  The pull stud 630 is a member to which a pulling force or a pushing force is applied from the grindstone shaft side (not shown), and at one end thereof, a screw portion 630a for being screwed into the screw hole portion 620c of the pressing plate 620 is formed. The pressing plate 620 is screwed and fixed. In addition, the distal end portion on the other end side includes a protruding portion 631 having an inclined portion 631a and a neck portion 632 having a diameter smaller than the outer diameter of the protruding portion 631.

  In the above-described configuration, the grindstone wheel 610, the pressing plate 620, and the pull stud 630 are formed and assembled as separate parts, but any two parts or all parts may be integrally formed. .

  FIG. 2 is a diagram showing a grinding wheel 600 according to an embodiment of the present invention and a grinding wheel drive main shaft 700 to which the grinding wheel 600 is attached and detached, and a diagram showing that the grinding wheel driving main shaft 700 is in an unclamped state. is there.

  The grindstone drive spindle 700 includes a grindstone shaft 710, a collet chuck 720, a clamp unit 730, and a draw bar 740. The grindstone drive spindle 700 is rotationally driven by a rotational drive device such as a motor or an air spindle (not shown).

  The grindstone shaft 710 is formed with a tapered portion 710a that fits in the tapered hole 610c of the grindstone wheel 610 on the outer peripheral portion of the tip, and is perpendicular to the central axis CL of the grindstone shaft 710 and contacts the second end surface 610b of the grindstone wheel 610. A contacting grindstone shaft end surface 710b is formed on the stepped portion 710e. Further, a grindstone shaft guide hole 710c through which the collet chuck 720, the clamp unit 730, and the draw bar 740 are movably fitted penetrates through the central portion of the grindstone shaft 710.

  A plurality of collet chuck segments 721 are attached to the clamp unit 730 through a collet detent pin 750 so as to be openable and closable, thereby forming a collet chuck 720. The clamp unit 730 is screwed to the draw bar 740.

  As described above, the collet chuck 720, the clamp unit 730, and the draw bar 740 are mounted in the grindstone shaft guide hole 710c of the grindstone shaft 710 so as to be slidable in the central axis CL direction.

  In FIG. 2, the draw bar 740 of the grindstone driving spindle 700 is pushed by the pushing force in the direction A in the figure, and each collet chuck segment 721 of the collet chuck 720 is open, that is, the grindstone driving spindle 700 is in an unclamped state. When the draw bar 740 is pushed in the A direction in the figure, the clamp unit 730 screwed to the draw bar 740 is also pushed in the A direction, and a plurality of collet chuck segments 721 attached to be openable / closable via the spring 740 are also pushed in the A direction. It is. At this time, since the projection 710d is formed at a position corresponding to the collet chuck segment base portion 721a in the grinding wheel shaft guide hole 710c of the grinding wheel shaft 710, when the collet chuck segment 721 is pushed in the direction A, the collet fulcrum The collet chuck segment base portion 721a is pushed inward by the projection 710d with the portion 730a as a fulcrum, thereby opening the collet chuck segment tip 721b outward. This state is an unclamped state in which the grinding wheel 600 shown on the left side of FIG. 2 can be mounted on the grinding wheel drive spindle 700 shown on the right side.

  FIG. 3 shows that the draw bar 740 of the grinding wheel drive spindle 700 is pulled in by a pulling force in the B direction shown in the figure, each collet chuck segment 721 of the collet chuck 720 is closed, and the pull stud 630 is pulled in the B direction in the drawing to clamp the grinding wheel 600. It is a figure which shows the state which carried out.

  From the state of FIG. 2, the grinding wheel 600 and the grinding wheel drive main shaft 700 approach each other by relative movement, and the pull stud 630 is inserted into the inner diameter region of the collet chuck 720. At this time, when the draw bar 740 is pulled by the pulling force in the B direction in the drawing, the clamp unit 730 and the collet chuck 720 are also drawn in the B direction in the drawing. When the collet chuck segment 721 moves in the direction B shown in the drawing, the pressing force to the collet chuck segment base portion 721a by the projection 710d is released, and the outer tapered portion 721c of the collet chuck segment tip 721b becomes the grindstone shaft guide hole 710c. , The collet chuck segment tip 721b is closed and stored in the direction B in the figure. By this operation, the gripping portion 721d is fitted to the neck portion 632 of the pull stud 630, and the inner tapered portion 721e is joined to the inclined portion 631a to further apply a pulling force in the B direction in the drawing.

  Here, the tapered hole portion 610 c of the grinding wheel 610 is pressed against the tapered portion 710 a of the grinding wheel shaft 710, and the second end surface 610 b of the grinding wheel 610 is pressed against the grinding wheel shaft end surface 710 b of the grinding wheel shaft 710. Accordingly, the grindstone wheel 610 is constrained by two surfaces by the grindstone shaft 710.

  FIG. 4 is a diagram showing that the draw bar 740 is moved in the direction A in the figure by the pushing force from the clamped state to be in an unclamped state.

  When the draw bar 740 is moved in the direction A in the drawing by the pushing force from the clamped state in FIG. 3, the collet chuck segment 721 is also pushed in the direction A and moved, and the collet chuck segment base portion 721a with the collet fulcrum portion 730a as a fulcrum. Is pushed inward by the protrusion 710d, and thereby the collet chuck segment tip 721b opens outward. Therefore, the pressure contact between the tapered hole portion 610c of the grinding wheel 610 and the taper portion 710a of the grinding wheel shaft 710, and the pressure contact between the second end surface 610b of the grinding wheel 610 and the grinding wheel shaft end surface 710b of the grinding wheel shaft 710, that is, the grinding wheel. The two-surface restriction between 610 and the grindstone shaft 710 is released. Therefore, the grinding wheel 600 is in an unclamped state that can be detached from the grinding wheel drive spindle 700.

(Effect of the embodiment of the present invention)
The embodiment of the present invention has the following effects.
(1) The tapered hole portion 610c of the grindstone wheel 610 and the tapered portion 710a of the grindstone shaft 710, and the second end surface 610b of the grindstone wheel 610 and the grindstone shaft end surface 710b of the grindstone shaft 710 are press-contacted together, so-called two-surface restraint. Since the grinding wheel 600 is held, it is possible to attach and detach the grinding wheel with small runout and small axial displacement.
(2) Since the grinding wheel 600 having a pull stud is retracted by the collet chuck 720 on the grinding wheel driving spindle 700 side and fixed to the grinding wheel shaft 710, automatic replacement is possible when the grinding wheel is attached or detached, and the tool is replaced by an automatic tool change tool. It becomes possible to apply to a combined processing machine that performs processing by exchanging.
(3) Since the grindstone wheel and the grindstone shaft are joined by the tapered hole formed in the inner diameter portion of the grindstone wheel, the grinding point is located within the taper shape range, and the grinding load is reduced. The displacement of the grinding point can be reduced, and the radial rigidity of the grinding wheel 600 can be improved.
(4) By using a standardized clamp unit that can accommodate the grinding wheel shaft guide hole 710c of the grinding wheel drive main shaft 700, it is possible to relatively easily change the grinding wheel wheel clamping force according to the grinding load. As a unit standardized in the clamp part, for example, a BT clamping unit or the like can be applied.
(5) Since the outer diameter or inner diameter of the contact portion 620b of the pressing plate 620 is substantially the same as the outer diameter or inner diameter of the first end surface 610a formed on the grinding wheel 610, the force from the pressing plate 620 Transmits the inside of the grinding wheel 610 and works efficiently on the second end surface 610b, and the clamped state between the grinding wheel 610 and the grinding wheel shaft 710 becomes more stable.

(Example of application of the embodiment of the present invention to a multi-task machine)
Below, the case where the attachment / detachment structure of the grinding wheel which concerns on embodiment of this invention is applied to a multi-tasking machine is demonstrated.

  FIG. 5 is a plan view of a combined processing machine to which the grinding wheel attaching / detaching structure according to the embodiment of the present invention is applied. In FIG. 5, the X direction is defined vertically and the Z direction is defined horizontally.

  The multi-task machine 1 is controlled by a computer numerical control device (CNC) (not shown) and is composed of a multi-task machine body and an accessory device (not shown). Main accessory devices include an oil supply device, a cooling device, an air supply device, a coolant supply device, a chip collecting device, a duct device for connecting these devices to the multi-tasking machine body, and the like.

  The multi-tasking machine 1 is placed on a bed 10 and supports a workpiece or a long workpiece W so as to be rotationally driven, and is mounted on the bed 10 to move in the X and Z directions. And an X stage 301 and a Z stage 302 for positioning, a workpiece processing unit 200 that is mounted on the Z stage 302 so as to be detachable, and a processing tool is attached to and detached from a predetermined position of the workpiece processing unit 200. A tool mounting unit 400. The workpiece processing unit 200 not only moves in the X and Z directions by the X stage 301 and the Z stage 302, but also moves in the XZ plane by a so-called parallel mechanism in which closed link mechanisms are arranged in parallel, for example. It may be.

  The work support drive unit 100 includes a headstock base 101 placed on a bed 10 and left and right headstocks 103 that are slidably movable via left and right headstock slide guides 102. Is equipped with a main shaft drive motor 104 for driving the main shaft 105 to rotate at a predetermined rotational speed. Each of the left and right headstocks 103 is configured to be able to slide in the Z direction independently on the left and right sides, hold the workpiece W between predetermined centers, and fix the position thereof. The workpiece W is rotationally driven via a non-illustrated rotating metal to rotate the main shaft 105.

  The workpiece processing unit 200 includes a tool rotation main shaft 202 that is rotatably supported by a unit housing 201, and a tool drive motor 203 that rotationally drives the tool rotation main shaft 202 at a predetermined rotation speed. . Here, as the tool rotation main shaft 202, the structure of the grindstone driving main shaft 700 in the grinding wheel attaching / detaching structure according to the embodiment of the present invention described above can be applied. FIG. 5 shows a view in which the grinding wheel 600 according to the embodiment of the present invention is mounted on the tool rotation main shaft 202 as a processing tool.

  Note that the tool rotation main shaft 202 may be a rotation drive system using a gear or a belt, in addition to being directly connected to the tool drive motor 201 for rotation.

  The tool mounting unit 400 is placed at a predetermined position on the bed 10 and has a tool turret 403 having a plurality of tool pods 402 that can hold various processing tools 501 and a servo that performs indexing control around the X axis. The motor 404 is configured. The tool pod 402 is formed with a coupling portion 405 that can grip a part of the processing tool 501. The coupling part 405 may be one that mechanically grasps the processing tool 501 or one that is grasped by a magnet or the like.

  Here, the tapered hole portion 610c of the grinding wheel 600 according to the embodiment of the present invention can be applied to the tapered hole portion 510 of the processing tool 501.

  In addition to the grinding wheel 600 according to the embodiment of the present invention, the processing tool 501 includes a turning tool such as an electrodeposition wheel for turning used for turning, a drill used for drilling, grooving, and cutting such as an end mill. There are heat treatment tools as heat treatment tools such as tools and laser hardening heads, surface finishing tools used for superfinishing, ELID grinding and the like. In addition, when processing the workpiece | work W without rotationally driving a heat processing tool etc., the tool drive motor 201 is stopped and it processes.

  In FIG. 5, the case where the grinding wheel 600 mounted on the tool rotation spindle 202 is replaced with another processing tool 501 will be described. The X stage 301 and the Z stage 302 are used to move the machining tool to a predetermined position where the machining tool can be exchanged, and the grinding wheel 600 is gripped by the coupling portion 405 of the tool pod 402 not equipped with the machining tool 501 shown in FIG. . Thereafter, the clamp of the tool rotation main shaft 202 is released to be in an unclamped state, and the grinding wheel 600 is recovered to the tool mounting unit 400 side.

  Indexing control is performed by the servo motor 404, and the processing tool 501 is set at a position where it can be mounted on the tool rotation spindle 202. The tool rotation main shaft 202 is moved by the Z stage 302, the tool rotation main shaft 202 is mounted in the tapered hole 510 of the processing tool 501, and the processing tool 501 is mounted on the tool rotation main shaft 202 by being in a clamped state.

  Through the above series of operations, the desired processing tool 501 can be easily attached to and detached from the tool rotation main shaft 202. Since the machining tool can be exchanged by being programmed by a computer numerical control device, automatic tool exchange can be performed while performing various machining on the workpiece W. Therefore, by applying the grinding wheel attaching / detaching structure according to the embodiment of the present invention, a multi-task machine equipped with an automatic tool changer can be easily realized.

The structure of the grinding wheel which concerns on embodiment of this invention is shown, (a) shows the grinding wheel 600 assembled by the grinding wheel 610, the press plate 620, and the pull stud 630, (b) shows the press plate. 620 is a right side view of 620, and FIG. 6C is a view showing a left side view of the grindstone wheel 610. FIG. It is a figure which shows the grindstone 600 which concerns on embodiment of this invention, and the grindstone drive main axis | shaft 700 with which the grindstone 600 is attached or detached, It is a figure which shows that the grindstone drive main axis | shaft 700 is an unclamped state. The drawing bar 740 of the grindstone driving spindle 700 is pulled in by the pulling force in the B direction shown in the drawing, and each collet chuck segment 721 of the collet chuck 720 is closed, and the pull stud 630 is pulled in the B direction in the drawing to clamp the grinding wheel 600. FIG. It is a figure which shows that drawbar 740 was moved to the direction of illustration A by pushing force from the clamp state, and was in the unclamp state. It is a top view of the compound processing machine to which the attachment / detachment structure of the grinding wheel according to the embodiment of the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Combined processing machine 10 Bed 100 Work support drive unit 101 Spindle base 102 Spindle base slide guide 103 Spindle base 104 Spindle drive motor 105 Spindle 200 Work processing unit 201 Unit housing 202 Tool rotation spindle 203 Tool drive motor 301 X stage 302 Z stage 400 Tool mounting unit 402 Tool pod 403 Tool turret 404 Servo motor 405 Coupling portion 501 Processing tool 600 Grinding wheel 610 Grinding wheel 611 Grinding wheel 620 Press plate 630 Pull stud 700 Grinding wheel drive main shaft 710 Grinding wheel shaft 720 Collet chuck 730 Clamp unit 740 Drawbar 750 Collet Non-rotating pin

Claims (3)

A grindstone wheel that holds a grindstone on the outer peripheral portion, has an opening on the first end face side, and has a tapered hole portion that leads to the opening on the second end face side;
A pressing plate for contacting the first end surface side of the grinding wheel with a predetermined outer diameter and inner diameter, and applying a pressing force to the second end surface side of the grinding wheel;
A tapered portion that is inserted into the tapered hole portion of the grinding wheel, and a step portion that is formed stepwise with respect to the tapered portion and contacts the second end surface side of the grinding wheel with the predetermined outer diameter. A grinding wheel shaft having,
A clamp unit that is fitted in a guide hole formed in the center of the grindstone shaft and that can clamp the pullstat fixed to the pressing plate;
The clamp unit is configured to generate a predetermined contact pressure between the second end face side of the grindstone wheel and the stepped portion of the grindstone shaft, and between the tapered hole portion and the tapered portion. Apply axial tension to the pressing plate,
The grindstone that the grindstone wheel holds on the outer periphery is located within the axial width of the tapered hole formed in the grindstone wheel ,
The grinding wheel mounting / demounting structure is characterized in that the pressing plate has substantially the same diameter as a contact surface that is in contact with an end surface of the grinding wheel shaft on a second end surface side of the grinding wheel .   The said grindstone wheel is restrained by two surfaces of the taper hole part fitted to the said grindstone shaft, and the contact surface which the end surface of the said grindstone shaft contacts the 2nd end surface side of the said grindstone wheel. 2. A structure for attaching and detaching a grinding wheel according to 1. The said clamp unit gives drawing force or pushing force to the pull stud fixed to the said press plate via a collet chuck by the draw bar with which the said grindstone axis | shaft was equipped. Detaching structure for the described grinding wheel.