Cut-out tool holder

Abstract

To provide an indexing tool holder capable of converting linear motion of a polishing tool into a rotation step operation, and automatizing rotation of a prescribed angle of the polishing tool by being attached to an NC machine tool.SOLUTION: An indexing tool holder comprises: drive means in which a linear drive part is stored in an indexing tool holder body, and reciprocating and moving linearly the linear drive part; a linear motion groove in which, there is provided a guide groove on a facing surface of the linear drive part facing the indexing tool holder body, to which a protrusion member is engaged, the protrusion member energized toward the linear drive part from the indexing tool holder body, in which the guide groove has a depth which has a longitudinal direction parallel to the linear direction and which is varied according to the position of an indexing rotation angle; and an inclination groove which has a longitudinal direction in a direction crossing the linear direction, and whose depth is varied, among indexing rotation angles. The linear groove and inclination groove are alternately arranged along a circumferential direction of the linear drive part, and are continuously arranged so as to circulate on the facing surface of the linear drive part in the circumferential direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a indexing tool holder that utilizes a groove mechanism for converting a linear motion into a rotational step motion (hereinafter referred to as an indexing motion).

Background Art

[0002] In cutting processes for metals, resins, etc., when using machine tools such as lathes and cylindrical grinding machines, burrs that protrude outward are generated at the edge portions of the processed products. The presence of such burrs may cause problems in subsequent processes and the assembly of parts, and may also affect the functions of the products, so they need to be removed.

[0003] The generation of burrs in cutting processes is caused by the plastic deformation occurring on the processed surface, where the portion protruding outside the edge is left uncut. However, depending on the material of the workpiece and the shape of the processed product, etc., the size and location of the burrs vary. Therefore, as a method for removing burrs, the processed products have been rotated and manually polished using abrasive brushes, grindstones, sandpaper, etc.

[0004] However, such manual polishing needs to be performed one by one for each workpiece, which requires labor and time.

[0005] Also, recent machine tools are equipped with an interlock that prevents the lathe from operating with the safety door open for ensuring safety. For example, the interlock device described in Patent Document 1 is known. In machine tools equipped with such an interlock device, it has become difficult to rotate the workpiece spindle and perform manual polishing with the safety door open.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] For the reasons described above, instead of manual polishing, as one of the processing tools of an NC machine tool, a polishing tool such as a polishing brush or a grinding wheel can be attached, and the polishing tool can be moved by an NC program to perform polishing. However, general machine tools such as NC lathes rotate the workpiece and press a processing tool such as a tool that moves linearly or curvilinearly against the workpiece for processing, so the processing tool side cannot be rotated. When a cylindrical polishing tool is attached to such an NC machine tool for polishing, only a part of the cylindrical side surface of the polishing tool comes into contact with the workpiece, and it is difficult to use the entire circumference of the cylindrical side surface. Also, when it is desired to change the action point of the polishing tool with respect to the workpiece, it is necessary to temporarily stop the processing by the machine tool, manually change the rotation angle of the polishing tool, and re-fix it. Although a method using a rotating tool can also be considered, a high cost is incurred for attaching the unit of the rotating tool.

[0008] Therefore, the present invention has been made in view of the above matters, and an object of the present invention is to provide a dividing tool holder that can automate the rotation of a polishing tool by a predetermined angle by converting the linear motion of the polishing tool into a rotational step motion and attaching it to an NC machine tool.

Means for Solving the Problems

[0009] This invention has been made to achieve the above object, and is characterized by the following.

[0010] The indexing tool holder according to the present invention is an indexing tool holder that can convert the movement of a linear drive unit driven in the axial direction into a rotational movement of a certain angle and change the position of the working point of the tool. The linear drive unit is housed inside the indexing tool holder body, and there is a driving means for linearly reciprocating the linear drive unit. A guide groove with which a protruding member biased from the indexing tool holder body toward the linear drive unit engages is formed on the opposing surface of the linear drive unit with the indexing tool holder body. The guide groove has a linear movement groove with a changing depth having a longitudinal direction parallel to the linear movement direction at the position of the indexing rotation angle, and an inclined groove with a changing depth having a longitudinal direction in a direction intersecting the linear movement direction between the indexing rotation angles. The linear movement groove and the inclined groove are alternately arranged along the circumferential direction of the linear drive unit, and are continuously arranged so as to circulate in the circumferential direction on the opposing surface of the linear drive unit. is provided, and the straight-ahead drive unit includes a collet as a tool fixing means and a cap for tightening the collet, and an inner diameter tapered surface for receiving the collet is formed It is characterized by this.

[0011] In the indexing tool holder according to the present invention, it is preferable that the linear movement groove and the inclined groove include a base portion with the largest groove depth and a tip portion with the groove depth gradually decreasing along the longitudinal direction from the base portion.

[0012] In the indexing tool holder according to the present invention, it is preferable that the tip portion of either one of the linear movement groove and the inclined groove is continuously arranged with the base portion of the other one of the adjacent inclined groove and the linear movement groove.

[0013] In the indexing tool holder according to the present invention, in the reference state, it is preferable that the position in the linear movement direction of the base portion with which the protruding member engages is at two or more positions.

[0015] In the indexing tool holder according to the present invention, it is preferable that a resilient body for return movement that biases the linear drive unit in the linear movement direction is provided in the indexing tool holder body.

[0016] In the indexing tool holder according to the present invention, it is preferable that the driving means advances the linear drive unit by fluid pressure.

[0017] In the indexing tool holder according to the present invention, it is preferable that the driving means advances the linear drive unit by the mechanical movement of a linear motion unit attached to a machine tool.

[0018] In the indexing tool holder according to the present invention, it is preferable that the driving means abuts the linear drive unit against a fixed protrusion provided on a machine tool by the movement of a turret tool post according to an NC program, and advances the linear drive unit.

[0019] In the indexing tool holder according to the present invention, it is preferable that the driving means advances and retracts the linear drive unit by fluid pressure.

[0020] In the indexing tool holder according to the present invention, it is preferable that the fluid pressure is a coolant pressure used for a machine tool.

[0021] In the indexing tool holder according to the present invention, it is preferable that the tool to be attached is a polishing tool.

[0022] The above summary of the invention does not list all the features necessary for the present invention, and sub-combinations of these feature groups can also be inventions.

Effects of the Invention

[0023] According to the indexing tool holder of the present invention, with a simple structure, the linear motion of the polishing tool can be changed to a rotational step motion. Further, by attaching it to an NC machine tool, the rotational step motion of the polishing tool can be automated in an inexpensive manner, and the acting point of the polishing tool on the workpiece can be changed.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0025] Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. Note that the following embodiments do not limit the invention according to each claim, and not all combinations of the features described in the embodiments are essential for the solution means of the invention.

[0026] FIG. 1 is a perspective view showing an example of an NC machine tool to which a indexing tool holder according to an embodiment of the present invention is attached, and FIG. 2 is a cross-sectional view of the indexing tool holder according to the first embodiment of the present invention, where (a) is a partial cross-sectional view showing a reference state, (b) is a partial cross-sectional view showing a forward state, and (c) is a cross-sectional view taken along line A-A of FIG. 2(a). In this specification, the “front-rear direction” and the “linear movement direction” are defined as the directions indicated by the arrows in FIG. 2. Further, in this specification, “indexing” means stepping the position by a predetermined angle around the axis center and rotating. Also, in this specification, “coolant pressure” means the pressure of the cutting fluid used for machining.

[0027] [Usage example of indexing tool holder] The indexing tool holder according to the present invention holds a polishing tool or the like and is attached to a turret tool post 100 provided in a machine tool such as an NC lathe, as shown in FIG. 1, via a turret tool holder 101.

[0028] The NC lathe shown in FIG. 1 includes a spindle headstock 200 that rotates a workpiece at a position facing the turret tool post 100, and a chuck 201 for fixing the workpiece is attached to the tip of the spindle headstock 200. Such an NC lathe uses the rotation of the spindle headstock 200 to which the workpiece is attached as the main movement for cutting or polishing, and the linear or curvilinear movement of the turret tool post 100 to which the indexing tool holder according to the present invention and cutting tools are attached as the feed movement, and is mainly used for cutting out cylindrical products. In this embodiment, the case where the indexing tool holder is attached to an NC lathe having a turret tool post 100 has been described. However, the machine tool in which the indexing tool holder is used is not limited to this, and other machine tools such as a comb-type tool post may be used.

[0029] [First embodiment] [Component configuration of indexing tool holder] As shown in Fig. 2, the indexing tool holder 1 according to this embodiment includes a linear drive unit 10 that grips a deburring tool 41 which is a polishing tool, and an indexing tool holder body 30 that slidably houses the linear drive unit 10 in the front-rear direction. Further, in front of the indexing tool holder body 30, an elastic body 35 for return movement that biases the linear drive unit 10 in the front-rear direction is provided via a spring cap 36, and on the cylindrical side surface of the indexing tool holder body 30, a stopper unit 50 that biases the linear drive unit 10 perpendicular to the front-rear direction is provided.

[0030] The linear drive unit 10 is composed of a substantially cylindrical linear drive member 11, a collet 42 that grips the deburring tool 41, and a collet nut 43 for fixing the collet 42.

[0031] The linear drive member 11 has a cylindrical sliding portion 12 having a cylindrical side surface slidable with respect to the inner diameter surface of the indexing tool holder body 30, and a substantially cylindrical shaft portion 15 that is located in front of the cylindrical sliding portion 12 and is formed coaxially with the axis of the cylindrical sliding portion 12.

[0032] As shown in Fig. 2(a), the cylindrical sliding portion 12 has a cylindrical side surface that forms a predetermined clearance with the inner diameter surface of the indexing tool holder body 30 so that the linear drive unit 10 can slide appropriately by the coolant pressure described later. Further, it is preferable that the cylindrical side surface of the cylindrical sliding portion 12 is finished with a smooth surface so that it can slide smoothly with respect to the indexing tool holder body 30. In addition, in order to prevent leakage of the coolant generated by the clearance between the indexing tool holder body 30 and the cylindrical sliding portion 12, a circumferential groove may be provided at the rear end of the cylindrical side surface of the cylindrical sliding portion 12, and a sealing material such as an O-ring may be attached.

[0033] Further, on the cylindrical side surface of the cylindrical sliding portion 12, as shown in FIG. 3(a), a plurality of linear motion grooves 21 having a longitudinal direction parallel to the axial direction of the cylindrical sliding portion 12 and a plurality of inclined grooves 22 having a longitudinal direction in a direction intersecting the axial direction are formed. The linear motion grooves 21 and the inclined grooves 22 engage with a sphere 51 described later and function as guide grooves when the linear drive portion 10 performs a linear motion and an indexing operation. In the present embodiment, there are a plurality of embodiments regarding the arrangement of these grooves, and the linear motion and indexing operations of the linear drive portion 10 differ depending on the arrangement form of the grooves. The arrangement form of the grooves in the present embodiment and the operation of the linear drive portion 10 will be described in detail later.

[0034] Further, on the front end surface of the cylindrical sliding portion 12, a shaft portion 15 having a cylindrical side surface smaller than the outer diameter of the cylindrical side surface of the cylindrical sliding portion 12 extends, and a spring support surface 16 for supporting the seating surface of the return elastic body 35 is formed between the front outer edge of the cylindrical sliding portion 12 and the cylindrical side surface of the shaft portion 15.

[0035] The cylindrical side surface of the shaft portion 15 is formed to have an outer diameter smaller than the inner diameter of the return elastic body 35 and penetrates the inner diameter side of the return elastic body 35. It is preferable that the outer diameter of the shaft portion 15 is formed so as to ensure an appropriate clearance with the inner diameter of the return elastic body 35 so that there is no rubbing with the return elastic body 35. Further, in order to prevent contact between the return elastic body 35 and the shaft portion 15, the outer diameter of the shaft portion 15 on the spring support surface 16 side may be increased and a stepped guide may be provided.

[0036] A deep hole capable of accommodating a collet 42 is formed in the shaft portion 15, and an inner diameter tapered surface 17 that can be fitted to the side surface of the collet 42 is provided near the entrance of the deep hole. Further, a screw portion 18 for tightening a collet nut 43 is formed at the tip of the shaft portion 15. When tightening the collet nut 43, it is preferable that parallel two planes 19 that can be gripped by a tool such as a wrench are formed behind the screw portion 18 in order to suppress the rotation of the linear drive member 11.

[0037] According to the shaft portion 15 formed in this way, for example, as shown in Fig. 2(a), by tightening the collet nut 43 assembled to the threaded portion 18, the side surfaces of the collet 42 with radially alternating circumferential grooves in the front and rear in the longitudinal direction are pressed against the inner diameter tapered surface 17, and the inner diameter surface of the collet 42 is reduced substantially in parallel, enabling the burr removal tool 41 to be gripped. Note that the gripping method of the burr removal tool 41 is not limited to the structure of such an inner diameter tapered surface 17 and the collet 42, and known fixing methods can be used.

[0038] As shown in Fig. 2(a), the indexing tool holder body 30 has an inner diameter surface that forms a predetermined clearance with the cylindrical side surface of the cylindrical sliding portion 12 so that the straight drive portion 10 can slide appropriately by the coolant pressure described later. Further, it is preferable that the inner diameter surface of the indexing tool holder body 30 is finished with a smooth surface so that the straight drive portion 10 can slide smoothly.

[0039] Further, the indexing tool holder body 30 has a cylindrical side surface that is inserted into the inner diameter of the turret tool holder 101. A circumferential groove is formed at the rear end of the cylindrical side surface, and an O-ring for preventing leakage of the coolant described later is attached. Note that it is preferable that the rear edge portion of the indexing tool holder body 30 is chamfered or the like to prevent damage to the O-ring and facilitate attachment.

[0040] Further, the cylindrical side surface of the indexing tool holder body 30 has a pressing surface 31 that serves as a fixing mechanism for restraining movement in the rotational direction and the front and rear directions when the indexing tool holder 1 is attached to the turret tool holder 101, and a through hole 32 for attaching the stopper portion 50.

[0041] As shown in an example in Fig. 6, the pressing surface 31 is a flat surface formed on the outer diameter surface of the indexing tool holder body 30, and is formed at a position corresponding to the set screw 103 attached to the turret tool holder 101. The indexing tool holder 1 is attached to the turret tool holder 101 with its movement in the rotational direction and the front-rear direction restricted by fastening the set screw 103. In the present embodiment, the case where the pressing surface 31 is a continuous flat surface corresponding to the positions of two set screws 103 arranged side by side in the axial direction of the indexing tool holder 1 has been described. However, the position and arrangement of the pressing surface 31 are not limited to this, and it may be divided into a plurality in accordance with the position of at least one set screw 103. Also, as a fixing mechanism of the indexing tool holder 1 to the turret tool holder 101, known means such as a key may be used.

[0042] As shown in Figs. 2(a) and (c), the through hole 32 is a through hole formed in a direction perpendicular to the axial direction of the indexing tool holder body 30. The side surface of the through hole 32 located on the inner diameter side of the indexing tool holder body 30 is formed so that a sphere 51 described later can be fitted therein, and a screw portion for screwing a set screw 53 described later is formed on the side surface of the through hole 32 located on the outer diameter side of the indexing tool holder body 30.

[0043] The elastic body 35 for return movement passes through the shaft portion 15 and is housed in the inner diameter of the indexing tool holder body 30, and a compression coil spring is preferably used. One seating surface of the elastic body 35 for return movement is supported by the spring support surface 16 of the direct drive member 11, and the other seating surface is supported by a spring cap 36 described later, and it is attached in a state where the direct drive unit 10 is biased rearward with a predetermined load.

[0044] The spring cap 36 has a shaft portion 15 passing through its center and is attached to the front end face of the indexing tool holder body 30 by a fastening member such as a bolt. Note that the attachment method of the spring cap 36 is not limited to that using a bolt or the like, and any attachment method capable of resisting the spring load of the resilient member 35 for reciprocation may be used, such as other attachment methods. For example, the spring cap 36 and the indexing tool holder body 30 may be provided with mating screw threads and screwed together, or may be attached by known attachment means such as mechanical joining by caulking. Further, the indexing tool holder body 30 may be formed in a shape integrated with the spring cap 36.

[0045] The stopper portion 50 is attached to the through-hole 32 of the indexing tool holder body 30 and is composed of a sphere 51, a resilient member 52 for the sphere, and a set screw 53.

[0046] The sphere 51 contacts the bottom surface of the linear motion groove 21 or the inclined groove 22. The resilient member 52 for the sphere is positioned between the sphere 51 and the set screw 53. The set screw 53 is screwed into the threaded portion of the through-hole 32 and supports one seating surface of the resilient member 52 for the sphere. At this time, the resilient member 52 for the sphere is biased by a predetermined load, and the sphere 51 presses against the bottom surface of the linear motion groove 21 or the inclined groove 22. Further, the total length of the set screw 53 is formed such that when attached to the through-hole 32, the head does not protrude from the outer diameter of the indexing tool holder body 30. In the present embodiment, the case where the sphere 51 is spherical has been described. However, the shape of the sphere 51 is not limited to this, and any protruding member having a smooth roundness at the tip may be used, such as a bullet-shaped pin.

[0047] [Arrangement forms of the linear motion groove and the inclined groove, and linear motion and indexing operations of the linear drive unit] Next, the arrangement forms of the linear motion groove and the inclined groove provided in the cylindrical sliding portion 12 of the linear drive member 11, and the linear motion and indexing operations of the linear drive unit 10 in each arrangement form will be described in detail.

[0048] FIG. 3(a) is a front view of a linear drive member having the groove arrangement form A of the present invention, FIG. 4(a) is a front view of a linear drive member having the groove arrangement form B of the present invention, and FIG. 5(a) is a front view of a linear drive member having the groove arrangement form C of the present invention.

[0049] [Groove arrangement form A] As shown in FIG. 3(a), the groove arrangement form A in the present embodiment is composed of a plurality of linear grooves 21 having a longitudinal direction parallel to the axial direction of the cylindrical sliding portion 12 and a plurality of inclined grooves 22 having a longitudinal direction in a direction intersecting the axial direction. Note that the shapes of the groove bottom surfaces of the linear grooves 21 and the inclined grooves 22 are formed in an arc shape in a cross section orthogonal to the longitudinal direction of the grooves.

[0050] As shown in FIG. 3(b), the linear groove 21 has a base portion 21a with the deepest groove depth on the front side of the cylindrical sliding portion 12, and has a tip portion 21b with a gradually decreasing groove depth along the longitudinal direction of the linear groove 21 from the base portion 21a. Note that the base portions 21a of the plurality of linear grooves 21 are arranged at equal angles, for example, along the circumferential direction of the cylindrical sliding portion 12.

[0051] As shown in FIG. 3(c), the inclined groove 22 has a base portion 22a with the deepest groove depth on the rear side of the cylindrical sliding portion 12, and has a tip portion 22b with a gradually decreasing groove depth along the longitudinal direction of the inclined groove 22 from the base portion 22a. Note that the base portions 22a of the plurality of inclined grooves 22 are arranged at equal angles, for example, along the circumferential direction of the cylindrical sliding portion 12. Further, it is preferable that the inclined groove 22 changes in depth along the circular arc of the right-angled cross section of the cylindrical side surface of the cylindrical sliding portion 12.

[0052] As shown in Fig. 3(a), the linear movement groove 21 and the inclined groove 22 are arranged such that the base portion 22a of the inclined groove 22 is located on the longitudinal axis of the linear movement groove 21, and the linear movement groove 21 is connected to the inclined groove 22. Further, on the longitudinal axis of the inclined groove 22, the base portions 21a of the adjacent linear movement grooves 21 are located, and the inclined groove 22 is connected to the adjacent linear movement grooves 21. The linear movement groove 21 and the inclined groove 22 maintain the above-described positional relationship and are repeatedly arranged along the circumferential direction of the cylindrical sliding portion 12. Therefore, on the cylindrical side surface of the cylindrical sliding portion 12, the linear movement groove 21 and the inclined groove 22 are alternately continuous, and a circulation groove that makes one round in the circumferential direction is formed.

[0053] According to the arrangement of the linear movement groove 21 and the inclined groove 22 as described above, as shown in Fig. 3(b), the base portion 22a with a deep groove depth and the tip portion 21b with a shallow groove depth are connected, and as shown in Fig. 3(c), the base portion 21a with a deep groove depth and the tip portion 21b with a shallow groove depth are connected. Therefore, at the connection portion between the linear movement groove 21 and the inclined groove 22, a step 23 composed of a gentle bottom surface and a steep bottom surface is formed. It is preferable that the edge portion of the step 23 is smoothly connected.

[0054] Next, the operation of the linear drive unit 10 having the groove arrangement form A as described above during linear movement and indexing will be described.

[0055] A state where the linear drive unit 10 is not receiving an external load (hereinafter referred to as the "reference state") is shown in Fig. 2(a). In the reference state, the linear drive unit 10 is biased rearward in the linear movement direction by the return elastic body 35, and the spherical body 51 is stationary by engaging with the base portion 21a of the linear movement groove 21.

[0056] When a load is applied to the straight - drive unit 10 in the reference state from the rear by the driving means described later, it slides on the inner diameter of the indexing tool holder body 30, deflects the elastic body 35 for return movement, and moves forward. At this time, the straight - drive unit 10 moves linearly as the linear movement groove 21 is guided by the spherical body 51, and the pressure - contact position of the spherical body 51 moves from the base portion 21a shown in Fig. 3(b) along the linear movement groove 21 to the tip portion 21b. Further, when the straight - drive unit 10 moves forward, the pressure - contact position of the spherical body 51 crosses the step 23 and shifts to the base portion 22a of the inclined groove 22. At this time, as shown in Fig. 2(b), the spherical body 51 engages with the base portion 22a, and the straight - drive unit 10 stops moving forward. (Hereinafter, this state is referred to as the "forward state".)

[0057] When the load from the driving means is removed from the straight - drive unit 10 in the forward state, a load is applied to the straight - drive unit 10 so as to be pushed back from the front by the repulsive force of the biased elastic body 35 for return movement, and the straight - drive unit 10 moves backward. At this time, the straight - drive unit 10 moves backward while rotating about the axis as the inclined groove 22 is guided by the spherical body 51, and the pressure - contact position of the spherical body 51 moves from the base portion 22a shown in Fig. 3(c) along the inclined groove 22 to the tip portion 22b located in the front.

[0058] As described above, the inclined groove 22 is formed such that the groove depth gradually becomes shallower from the base portion 22a to the tip portion 22b, while the slope of the step 23 leading from the base portion 22a to the linear movement groove 21 is formed steeply. Therefore, when the straight - drive unit 10 moves backward, the pressure - contact position of the spherical body 51 located at the base portion 22a surely selects the inclined groove 22 without crossing the step 23 again and returning to the linear movement groove 21.

[0059] After that, when the straight - drive unit 10 is further pushed back, the pressure - contact position of the spherical body 51 crosses the step 23 and shifts to the base portion 21a of the linear movement groove 21 that connects to the inclined groove 22, and the straight - drive unit 10 stops moving backward. At this time, since the base portion 21a with which the spherical body 51 engages is the base portion 21a of the linear movement groove 21 adjacent to the linear movement groove 21 that engaged in the reference state, the straight - drive unit 10 is in a state of rotating by a predetermined angle with respect to the reference state.

[0060] In this way, by linearly reciprocating the linear drive unit 10 with the drive means and the return elastic body 35, the indexing of the linear drive unit 10 can be performed. Further, since the linear groove 21 and the inclined groove 22 are continuous circulation grooves that circle around in the circumferential direction, the linear drive unit 10 can be repeatedly linearly reciprocated to continue the indexing of the linear drive unit 10.

[0061] Also, according to the groove arrangement form A, when the linear drive unit 10 moves forward, only the linear movement is performed without performing the indexing operation. Therefore, the load on the linear drive unit 10 of the drive means that is required only needs to be able to compress the return elastic body 35, and can be made smaller than the case of compressing the return elastic body 35 while accompanying the indexing operation. Further, when a compression coil spring is used for the return elastic body 35, since the indexing operation is performed by the extension of the compressed compression coil spring, the shortening of the compression coil spring and the indexing operation are not performed simultaneously, and there is no possibility that the torsional force of the compression coil spring acting against the indexing rotation direction acts.

[0062] Also, by intersecting the longitudinal direction angle of the inclined groove 22 in the direction opposite to the axial direction of the cylindrical sliding portion 12, the indexing rotation direction of the linear drive unit 10 can be reversed.

[0063] [Groove arrangement form B]

[0064] Next, the groove arrangement form B to be described is different from the groove arrangement form A described above in the longitudinal direction angle of the inclined groove and the position of the base portions of the linear groove and the inclined groove, as shown in FIG. 4(a).

[0065] That is, for the inclined groove 22 of the groove arrangement form A, as shown in FIG. 3(a), the base portion 22a is located behind the cylindrical sliding portion 12, and the groove depth gradually becomes shallower in the direction intersecting the axial direction from the base portion 22a toward the front, whereas for the inclined groove 22' of the groove arrangement form B, as shown in FIG. 4(a), the base portion 22a' is located in front of the cylindrical sliding portion 12, and the groove depth is gradually formed shallower in the direction intersecting the axial direction from the base portion 22a' toward the rear.

[0066] Further, in the linear motion groove 21 of groove arrangement form A, the base portion 21a is located in front of the cylindrical sliding portion 12, and the groove depth gradually becomes shallower toward the rear in the axial direction. On the other hand, in the linear motion groove 21' of groove arrangement form B, the base portion 21a' is located behind the cylindrical sliding portion 12, and the groove depth is gradually formed shallower toward the front in the axial direction.

[0067] In addition, regarding other aspects such as the bottom surface shape of the groove and the connection portion between the linear motion groove and the inclined groove, etc., they are formed by the same configuration as that of groove arrangement form A. For these configurations, the same reference numerals are given and detailed descriptions are omitted.

[0068] Next, the operation of the linear drive unit 10 having the groove arrangement form B as described above during linear motion and indexing will be described.

[0069] When the linear drive unit 10 is in the reference state, the linear drive unit 10 is biased rearward in the linear motion direction by the return elastic body 35, and the spherical body 51 is engaged with the base portion 22a' of the inclined groove 22' and thus is stationary.

[0070] When a load is applied to the linear drive unit 10 in the reference state from the rear by a driving means to be described later, it slides on the inner diameter of the indexing tool holder main body 30, deflects the return elastic body 35, and moves forward. At this time, the linear drive unit 10 moves forward while rotating about the axis as the inclined groove 22' guides the spherical body 51, and the pressure contact position of the spherical body 51 moves from the base portion 22a' along the inclined groove 22' to the tip portion 22b'. Further, when the linear drive unit 10 moves forward, the pressure contact position of the spherical body 51 crosses the step 23 and shifts to the base portion 21a' of the linear motion groove 21', and the linear drive unit 10 stops moving forward and reaches the forward state.

[0071] When the load from the forward driving unit 10 in the forward state is removed by the driving means, a load is applied to the forward driving unit 10 by the repulsive force of the biasing elastic body 35 for return movement, and the forward driving unit 10 moves backward. At this time, the forward driving unit 10 linearly moves backward as the linear movement groove 21' is guided by the spherical body 51, and the pressure contact position of the spherical body 51 moves from the base portion 21a' to the tip portion 21b' along the linear movement groove 21'. When the forward driving unit 10 is further pushed back, the pressure contact position of the spherical body 51 crosses the step 23 and shifts to the base portion 22a' of the inclined groove 22' adjacent to the base portion that was engaged in the reference state, and the backward movement of the forward driving unit 10 stops.

[0072] In this way, the indexing operation of the forward driving unit 10 according to the groove arrangement form A is performed when the forward driving unit 10 is pushed back by the repulsive force of the elastic body 35 for return movement and moves backward, while the indexing operation of the forward driving unit 10 according to the groove arrangement form B is different in that the indexing is performed when the forward driving unit 10 is pushed forward by the driving means.

[0073] [Groove arrangement form C] The groove arrangement form C to be described next is different from the above-described groove arrangement form A in that, as shown in FIG. 5(a), the positions of the bases of the adjacent linear movement grooves are alternately arranged before and after in the axial direction of the cylindrical sliding portion 12.

[0074] The base portion 24a of the linear movement groove 24 of the groove arrangement form C is formed with a distance L backward in the axial direction from the base portion 21a of the adjacent linear movement groove 21, and the linear movement groove 21 and the linear movement groove 24 are alternately arranged along the circumferential direction of the cylindrical sliding portion 12.

[0075] Further, the base portion 24a of the linear movement groove 24 is located on the longitudinal axis of the inclined groove 25, and the base portion 21a of the linear movement groove 21 is located on the longitudinal axis of the inclined groove 22. A circulation groove that is repeatedly and continuously connected in the order of the linear movement groove 21, the inclined groove 25, the linear movement groove 24, and the inclined groove 22 is formed on the cylindrical side surface of the cylindrical sliding portion 12. Since the base portions 22a and 25a of the inclined grooves 22 and 25 are arranged along the circumferential direction of the cylindrical sliding portion 12, the longitudinal directions of the inclined grooves 22 and 25 intersect at different angles with respect to the axial direction of the cylindrical sliding portion 12.

[0076] In addition, with regard to other aspects such as the bottom surface shape of the groove and the connection portion between the linear movement groove and the inclined groove, they are formed by the same configuration as that of the groove arrangement form A. For these configurations, the same reference numerals are used and detailed descriptions are omitted.

[0077] Next, the operation of the linear drive unit 10 having the groove arrangement form C as described above during linear movement and indexing will be described.

[0078] The linear drive unit 10 having the groove arrangement form C, similar to the case of having the groove arrangement form A, is pushed out from the reference state by the drive means to reach the forward state, and is pushed back by the repulsive force of the return elastic body 35 from the forward state, and indexing is performed when moving backward.

[0079] In the groove arrangement form C, as described above, the adjacent base portions 21a and 24a are arranged at positions separated by a distance L in the axial direction of the linear drive unit 10. Therefore, for example, in the initial reference state, when the sphere 51 is engaged with the base portion 21a, when the linear drive unit 10 performs a linear movement and an indexing operation and makes a round trip, the sphere 51 engages with the base portion 24a, and the operation of the linear drive unit 10 is completed in a state where it has advanced by a distance L in the axial direction with respect to the reference state.

[0080] That is, every time the linear drive unit 10 linearly reciprocates in the axial direction, the indexing is performed by changing the stop position in the axial direction back and forth. In the present embodiment, the positions of the base 21a and the base 24a are formed to be separated from each other by a distance L in the axial direction, and the case where the stop position of the linear drive unit 10 has two steps has been described. However, the positions of the bases are not limited to this. For example, the stop positions of the linear drive unit 10 may be formed to be separated by three or more steps.

[0081] [Driving means of linear drive unit] Next, the driving means of the linear drive unit 10 in the present embodiment will be described. The driving means in the present embodiment is roughly classified into a method of applying a load to the rear of the linear drive unit 10 by using the coolant pressure used in the NC machine tool and a method of applying a load to the rear of the linear drive unit 10 by mechanical operation.

[0082] [Driving means using coolant pressure] FIG. 6 shows an example of the driving means of the linear drive unit 10 using the coolant pressure. In this driving means, the indexing tool holder 1 is attached to an oil hole tool-compatible turret tool holder 101.

[0083] The oil hole tool-compatible turret tool holder 101 has a lid member 102 airtightly attached to the rear, and a sealed space 105 is formed between the indexing tool holder 1 and the lid member 102. Further, a coolant discharge port 104 communicating with the sealed space 105 is provided behind the turret tool holder 101 through a passage provided in the lid member 102. By discharging the coolant of the NC machine tool, the pressure in the sealed space 105 can be increased.

[0084] Between the indexing tool holder 1 and the turret tool holder 101, it is sealed by an O-ring attached to the rear end of the indexing tool holder body 30. Also, the clearance between the inner diameter surface of the indexing tool holder body 30 and the cylindrical side surface of the cylindrical sliding portion 12 is set so that the linear drive portion 10 can slide appropriately by the coolant pressure. For this reason, due to the pressure increase in the sealed space 105, surface pressure is applied to the rear end face of the linear drive portion 10, and the linear drive portion 10 is pushed forward. Regarding the drive of the linear drive portion 10 backward, as described above, when the coolant stops, the linear drive portion 10 is pushed back by the repulsive force of the return elastic body 35 applied to the front end portion of the cylindrical sliding portion 12.

[0085] Also, the configuration of the turret tool holder used for the drive means using the coolant pressure is not limited to the above. As shown in FIG. 7, a lid member 107 provided with a coolant inlet 108 may be airtightly attached to the rear of the turret tool holder 106. The coolant inlet 108 is provided with a connection structure such as a pipe taper screw and can be connected to a pipe or the like to which the coolant is supplied. Also, a sealed space 109 similar to the above is formed between the indexing tool holder 1 and the lid member 107. Using such a turret tool holder 106, the coolant may be directly introduced into the sealed space 109 to increase the pressure and drive the linear drive portion 10.

[0086] In this embodiment, a method of linearly reciprocating the linear drive portion 10 by applying a load due to the coolant pressure to the rear end face of the linear drive portion 10 and arranging the return elastic body 35 in front of the linear drive portion 10 has been described. However, the direction of applying the load is not limited to this. The return elastic body 35 may be arranged behind the linear drive portion 10, and a load due to the coolant pressure may be applied from the front of the linear drive portion 10 to linearly reciprocate the linear drive portion 10.

[0087] [Drive means using mechanical operation] Figure 8 shows an embodiment of the driving means of the linear drive unit 10 using mechanical operation. In this driving means, the indexing tool holder 1 is attached to a turret tool holder 110 with an open rear end.

[0088] In the NC machine tool using this driving means, a linear motion unit such as a cylinder is attached to the NC machine tool, and the tip end portion 111 of the piston rod of the linear motion unit is in contact with the rear end face of the linear drive unit 10. To drive the linear drive unit 10, the linear motion unit is operated to push in the tip end portion 111 of the piston rod, thereby moving the linear drive unit 10 forward. Regarding the drive of the linear drive unit 10 backward, as described above, the linear drive unit 10 is pushed back by the repulsive force of the elastic body 35 for double-acting applied to the front end portion of the cylindrical sliding portion 12.

[0089] Also, by utilizing the movement of the turret type tool rest 100 according to the NC program, the rear end face of the linear drive unit 10 may be brought into contact with a fixed projection or the like installed on the machine tool to move the linear drive unit 10 forward.

[0090] [Second Embodiment] The indexing tool holder 1 according to the first embodiment described above is an indexing tool holder that moves the linear drive unit 10 forward by a driving means and moves backward by the repulsive force of the elastic body 35 for double-acting to perform a linear motion and indexing operation. Next, the indexing tool holder 6 according to the second embodiment to be described is an indexing tool holder that linearly moves in the front-rear direction by a method different from that of the first embodiment and performs an indexing operation. Regarding the configurations that are the same as or similar to those of the first embodiment described above, the same reference numerals are given and detailed descriptions are omitted.

[0091] [Component Configuration of Indexing Tool Holder] Figure 9 is a cross-sectional view showing a state in which an indexing tool holder element according to the second embodiment of the present invention is attached to a turret tool holder.

[0092] As shown in FIG. 9, the indexing tool holder 6 according to the second embodiment is composed of a linear drive unit 60 that grips the turning tool 44 and a sleeve 80 that slidably houses the linear drive unit 60. Further, on the cylindrical side surface of the sleeve 80, a stopper unit 50 is provided that biases the linear drive unit 60 perpendicular to the front-rear direction.

[0093] As shown in FIG. 9, the linear drive unit 60 is composed of a substantially cylindrical linear drive member 61, a collet 42 that grips the turning tool 44, and a collet nut 43 for fixing the collet 42.

[0094] The linear drive member 61 has a cylindrical sliding portion 62 having a cylindrical side surface slidable with respect to the inner diameter surface of the sleeve 80, and a shaft portion 15 that is located in front of the cylindrical sliding portion 62 and is formed coaxially with the axis of the cylindrical sliding portion 12.

[0095] The cylindrical sliding portion 62 is slidable with respect to the inner diameter surface of the sleeve 80 and has circumferential grooves for attaching O-rings at both axial ends so that there is no leakage of coolant described later. It is preferable that the cylindrical side surface of the cylindrical sliding portion 62 is finished to have a smooth surface so as to be slidable smoothly with respect to the sleeve 80.

[0096] On the cylindrical side surface of the cylindrical sliding portion 62, a plurality of linear motion grooves 21 having a longitudinal direction parallel to the axial direction of the cylindrical sliding portion 62 and a plurality of inclined grooves 22 having a longitudinal direction in a direction intersecting the axial direction are formed, similar to the first embodiment. Since the groove arrangement form and the operation of the linear drive unit 60 implemented in this second embodiment are the same as those in the first embodiment, detailed description thereof is omitted.

[0097] The sleeve 80 slidably houses the direct drive unit 60 and has an inner diameter surface corresponding to the O-rings attached to both ends of the cylindrical sliding portion 62 so that there is no leakage of the coolant described later. It is preferable that the inner diameter surface of the sleeve 80 is finished to have a smooth surface so that the direct drive unit 60 can slide smoothly. Further, the overall length of the sleeve 80 is formed longer than the overall length of the cylindrical sliding portion 62. Therefore, as shown in FIG. 9, in a state where the indexing tool holder 6 is attached to the turret tool holder 112 described later, when in the reference state, a sealed space 115 is formed between the front end surface of the cylindrical sliding portion 62 and the front cover member 113 described later. Further, the overall length of the sealed space 115 is formed corresponding to the linear movement groove 21 and the inclined groove 22 provided on the cylindrical side surface of the cylindrical sliding portion 62 so that the front end surface of the cylindrical sliding portion 62 and the rear end surface of the front cover member 113 come into contact with each other in the forward movement state of the direct drive unit 60. For this reason, when the direct drive unit 60 performs a linear movement and indexing operation, the forward movement of the direct drive unit 60 stops when the front end surface of the cylindrical sliding portion 62 and the rear end surface of the front cover member 113 come into contact with each other, and it reaches the forward movement state.

[0098] The cylindrical side surface of the sleeve 80 has a pressing hole bottom surface 81 that serves as a fixing mechanism when the indexing tool holder 6 is attached to the turret tool holder 112, and a through hole 32 for attaching the stopper portion 50.

[0099] Further, the cylindrical side surface of the sleeve 80 is formed so as to have an appropriate fit with the inner diameter surface of the turret tool holder 112 so that there is no leakage of the coolant. Note that the assembly of the sleeve 80 to the turret tool holder 112 is not limited to the fitting as shown in FIG. 9, and a sealing material such as an O-ring may be used. In such a case, a circumferential groove is formed on the cylindrical side surface of the sleeve 80 or the inner diameter surface of the turret tool holder 112.

[0100] The indexing tool holder 6 of the second embodiment configured as described above is attached to a turret tool holder 112 having a front cover member 113 and a rear cover member 114 in the front and rear in the axial direction as shown in FIG. 9.

[0101] The front cover member 113 is formed with a through hole 116 for passing through the shaft portion 15, and is airtightly attached to the front end surface of the turret tool holder 112 by fastening means (not shown).

[0102] A circumferential groove is provided on the inner diameter surface of the through hole 116, and an O-ring for preventing leakage of coolant is attached between the through hole 116 and the shaft portion 15.

[0103] A predetermined gap 117 is formed between the rear end surface of the front cover member 113 and the front end surface of the sleeve 80 in the mounting state of the indexing tool holder 6. Further, a groove portion 120 communicating the inner diameter of the coolant inlet hole 118 and the sleeve 80 is formed at a position corresponding to the coolant inlet hole 118 on the rear end surface of the front cover member 113. In addition, in order to apply surface pressure to the front end surface of the cylindrical sliding portion 62 by the high-pressure coolant described later, it is preferable that a countersunk hole having an inner diameter smaller than the outer diameter of the cylindrical sliding portion 62 and communicating with the groove portion 120 is formed on the rear end surface of the front cover member 113.

[0104] A set screw 103 for restraining the movement of the indexing tool holder 6 in the rotational direction and the front-rear direction is attached to the turret tool holder 112. Further, a coolant inlet hole 118 having a connection structure with a pipe such as a pipe taper screw is provided at a position corresponding to the gap 117 in the turret tool holder 112.

[0105] The rear cover member 114 is airtightly attached to the rear end surface of the turret tool holder 112 by fastening means (not shown). Further, a coolant inlet hole 119 having a connection structure with a pipe such as a pipe taper screw is provided in the rear cover member 114. The front end surface of the rear cover member 114 is formed corresponding to the guide groove provided on the cylindrical side surface of the cylindrical sliding portion 62 so as to contact the rear end surface of the cylindrical sliding portion 62 in the reference state as shown in FIG. 9. Therefore, when the direct drive unit 60 performs a linear motion and an indexing motion, the backward movement of the direct drive unit 60 stops when the rear end surface of the cylindrical sliding portion 62 and the front end surface of the rear cover member 114 come into contact, and the reference state is reached.

[0106] [Driving means of the linear drive unit] Next, the driving means of the linear drive unit 60 in the present embodiment will be described. In the second embodiment, using a high pressure such as a high-pressure coolant used in an NC machine tool, the linear forward and backward movement and indexing operation of the linear drive unit 60 are performed.

[0107] When advancing the linear drive unit 60 in the reference state as shown in FIG. 9, the high-pressure coolant is discharged from the coolant inlet hole 119 of the rear cover member 114. At this time, the sealed space 115 is filled with the coolant, and the pressure from the coolant inlet hole 118 of the turret tool holder 112 is not supplied. Therefore, the pressure applied to the coolant inlet hole 119 advances the linear drive unit 60, and the coolant filling the sealed space 115 passes through the gap 117 and is discharged from the coolant inlet hole 118. Further, when the linear drive unit 60 advances, the front end surface of the cylindrical sliding portion 62 comes into contact with the front cover member 113, and the linear drive unit 60 stops advancing and enters the advancing state. At this time, the front end surface of the cylindrical sliding portion 62 is in communication with the coolant inlet hole 118 through the groove portion 120 formed in the front cover member 113.

[0108] Thereafter, when the linear drive unit 60 in the advancing state is retracted and an indexing operation is performed, the high-pressure coolant is discharged from the coolant inlet hole 118 of the turret tool holder 112. The high-pressure coolant applies surface pressure to the front end surface of the cylindrical sliding portion 62 through the groove portion 120 to retract the linear drive unit 60. At this time, no pressure is supplied from the coolant inlet hole 119 of the rear cover member 114, and the coolant filling the rear of the linear drive member 61 is discharged from the coolant inlet hole 119. Further, when the linear drive unit 60 retracts, the rear end surface of the cylindrical sliding portion 62 comes into contact with the front end surface of the rear cover member 114, and the linear drive unit 60 stops retracting and returns to the reference state.

[0109] Thus, according to the second embodiment, in the reference state, fluid pressure is applied to the front end face of the cylindrical sliding portion 62 of the linear drive unit 60, and the rear end portion is stationary in contact with the rear cover member 114. Therefore, compared with the first embodiment, the force for fixing the linear drive unit 60 in the front-rear direction is stronger, and not only the polishing tool but also the turning tool 44 can be attached to the indexing tool holder 6. As the turning tool 44, for example, a turning tool provided with a plurality of cutting edges can be used, and by performing an indexing operation corresponding to each cutting edge of the plurality of cutting edges, long continuous machining becomes possible.

[0110] As described above, according to the first and second embodiments, without providing special equipment, by utilizing the coolant pressure used in the NC machine tool and the operation of the turret tool post 100, the linear motion of the polishing tool can be changed to a rotational step motion. Therefore, in the deburring operation and polishing process by the NC machine tool, the rotation of polishing tools such as brushes and grindstones can be automated at a low cost, and the action point of the polishing tool on the workpiece can be automatically changed, so that the polishing tool can be used without waste in the circumferential direction. In addition, since it is no longer necessary to reattach conventional manually operated polishing tools and turning tools, etc., the production efficiency can be increased.

[0111] Note that in the above, the case where the coolant pressure used in the NC machine tool is utilized as the driving means of the linear drive unit has been described. However, the fluid pressure for driving the linear drive unit is not limited to that by the coolant pressure, and may be a pressure by hydraulic oil or the like used in general hydraulic equipment. Also, the described elements are the minimum necessary ones, and components for functional improvement may be appropriately added and assembled. For example, a disk-shaped component may be sandwiched between the spring support surface 16 and the elastic body 35 for reciprocating motion to eliminate the torsional force of the compression coil spring and make indexing rotation easier. It is clear from the description of the claims that forms with such changes or improvements can also be included in the technical scope of the present invention.

Description of Reference Numerals

[0112] 1 Cutting tool holder, 10 60 Linear drive unit, 11 61 Linear drive member, 12 62 Cylindrical sliding part, 15 Shaft part, 16 Spring support surface, 17 Inner diameter taper surface, 18 Thread part, 19 Parallel two planes, 21 21’ 24 Linear motion groove, 21a 21a’ 22a 22a’ 24a 25a Base part, 21b 21b’ 22b 22b’ 24b 25b Tip part, 22 22’ 25 Inclined groove, 23 Step, 30 Cutting tool holder body, 31 Pressing surface, 32 116 Through hole, 35 Elastic body for return motion, 36 Spring cap, 41 Burr removing tool, 42 Collet, 43 Collet nut, 44 Turning tool, 50 Stopper part, 51 Sphere, 52 Elastic body for sphere, 53 103 Set screw, 80 Sleeve, 81 Bottom surface of pressing hole, 100 Turret type tool post, 101 106 110 112 Turret tool holder, 102 107 Cover member, 104 Coolant discharge port, 105 109 115 Sealed space, 108 118 119 Coolant inflow hole, 111 Piston rod tip part, 113 Front cover member, 114 Rear cover member, 117 Gap, 120 Groove part, 200 Headstock, 201 Chuck.

Claims

1. A indexing tool holder that can convert the movement of a linear drive unit driven in the axial direction into a rotational movement of a certain angle and change the position of the working point of the tool, a driving means for accommodating the linear drive unit inside the indexing tool holder body and reciprocating the linear drive unit linearly, a guide groove with which a protruding member biased from the indexing tool holder body toward the linear drive unit engages is formed on the opposing surface of the linear drive unit with the indexing tool holder body, the guide groove has a linear movement groove with a changing depth having a longitudinal direction parallel to the linear movement direction at the indexing rotation angle position, and an inclined groove with a changing depth having a longitudinal direction in a direction intersecting the linear movement direction between the indexing rotation angles, the linear movement groove and the inclined groove are alternately arranged along the circumferential direction of the linear drive unit, and are continuously arranged so as to circulate in the circumferential direction on the opposing surface of the linear drive unit, the linear drive unit includes a collet as a tool fixing means and a cap for tightening the collet, and is characterized in that an inner diameter tapered surface for receiving the collet is formed. An indexing tool holder.

2. In the indexing tool holder according to claim 1, the linear movement groove and the inclined groove are characterized by having a base portion with the largest groove depth and a tip portion with a gradually decreasing groove depth along the longitudinal direction from the base portion. An indexing tool holder.

3. In the indexing tool holder according to claim 2, the tip portion of either one of the linear movement groove and the inclined groove is characterized by being continuously arranged with the base portion of the other one of the adjacent inclined groove and the linear movement groove. An indexing tool holder.

4. In the indexing tool holder according to claim 2 or 3, in the reference state, the position in the linear movement direction of the base portion with which the protruding member engages is two or more. An indexing tool holder.

5. In the indexing tool holder according to any one of claims 1 to 4, the indexing tool holder body is provided with a resilient body for return movement that biases the linear drive unit in the linear movement direction. An indexing tool holder.

6. In the indexing tool holder according to claim 5, the driving means is characterized by advancing the linear drive unit by fluid pressure. An indexing tool holder.

7. In the indexing tool holder according to claim 5, The indexing tool holder is characterized in that the driving means advances the linear drive unit by the mechanical movement of a linear motion unit mounted on a machine tool. **Claim 8** In the indexing tool holder according to claim 5, the driving means is characterized in that the linear drive unit is brought into contact with a fixed protrusion provided on the machine tool by the movement of a turret tool rest according to an NC program, and the linear drive unit is advanced. **Claim 9** In the indexing tool holder according to any one of claims 1 to 4, the driving means is characterized in that the linear drive unit is advanced and retracted by fluid pressure. **Claim 10** In the indexing tool holder according to claim 6 or 9, the fluid pressure is a coolant pressure used in the machine tool. **Claim 11** In the indexing tool holder according to any one of claims 1 to 10, the tool to be attached is a grinding tool.

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