JP6225593B2 - Sim breaker - Google Patents

Description

  The present invention relates to a shim breaker that is attached to a chip, which is a cutting blade used in a lathe, and breaks chips generated continuously when a workpiece is cut with the chip with an appropriate length.

Conventionally, as shown in FIG. 8A, a shim breaker 154 is attached to a rake face 153A of a tip 153 which is a cutting blade used in a lathe.
When cutting the workpiece with the tip 153, as shown in FIG. 8B, the tip 153 is moved to the workpiece rotation axis XJ while rotating the cylindrical workpiece W around the workpiece rotation axis XJ parallel to the X axis. The workpiece W is moved in the orthogonal Z-axis direction and pressed against the workpiece W, and the tip 153 is further moved in the X-axis direction to cut the workpiece W.
As shown in FIG. 8B, in the conventional shim breaker 154, the inclination direction DAJ of the guide surface 154A with respect to the rake face 153A of the chip 153 and the direction DKJ in which the chips WK extend are not parallel. Accordingly, the chips WK are guided at a gentler angle than the inclination angle of the guide surface 154A.
At this time, the chips WK generated when the workpiece W is cut with the chip 153 are bent while being guided along a simple flat guide surface 154A formed on the shim breaker 154, and usually have an appropriate length. Will be automatically broken.
However, when the sharpness of the cutting edge in the tip 153 is lowered, as shown in FIG. 8C, the chip WK may continue without being broken at the expected length. In such a case, the continuous chips reach the lathe drive unit and the like, and the drive unit and the like may bite the chip and the lathe may stop abnormally.

  Therefore, Patent Document 1 discloses a chip shredding method in which a high-pressure fluid is sprayed from a spray nozzle toward a chip extending beyond a shim breaker to forcibly bend the chip toward the workpiece. . The chips bent toward the workpiece while extending beyond the shim breaker eventually hit the workpiece and are automatically broken when they hit the workpiece.

Japanese Patent Laid-Open No. 60-127743

In the chip shredding method described in Patent Document 1, it is necessary to attach an injection nozzle that injects high-pressure fluid and piping that guides the high-pressure fluid to the injection nozzle at appropriate positions, which complicates the lathe structure. So it is not so preferable. Further, since the chips are broken by hitting the workpiece, it is not preferable that the cutting surface of the workpiece may be damaged.
The present invention was devised in view of such points, and with a simpler configuration, chips generated continuously during cutting with a chip do not hit the workpiece and break down to an appropriate length. It is an object of the present invention to provide a shim breaker that can be more reliably broken.

In order to solve the above problems, the shim breaker according to the present invention takes the following means.
First, a first invention of the present invention is a shim breaker that is attached to a chip that is a cutting blade used in a lathe and breaks chips generated continuously when a workpiece is cut with the chip.
The shim breaker is attached to the rake face of the chip, and a guide face is provided on the side facing the rake face on the side facing the workpiece, and a protrusion is provided on the side far from the rake face. The guide surface has a predetermined inclination angle with respect to the rake face and guides chips toward the projecting portion, and the projecting portion has a convex shape toward the workpiece with respect to the guide surface. It is formed to protrude.
The guide surface includes a first guide surface provided on a side close to the rake surface, and a second guide surface provided on a side far from the rake surface, and the guide surface in the first guide surface The inclination angle of the second guide surface with respect to the rake face is set to be larger than the inclination angle with respect to the rake face.
Further, the second guide surface is inclined so that the side closer to the protruding portion is farther from the workpiece than the side closer to the first guide surface, and the second guide surface in the direction in which chips extend during cutting. The first guide surface chip direction length, which is the length of one guide surface, is set longer than the second guide surface chip direction length, which is the length of the second guide surface in the direction in which the chips extend during cutting. When viewed from a direction parallel to the rotation axis of the workpiece, the protruding portion protrudes in an arcuate convex shape toward the workpiece.

In the first aspect of the invention, the chips generated continuously are guided from the guide surface to the projecting portion, and the chips guided from the guide surface are forced by the projecting portion projecting in a convex manner toward the workpiece. Bend greatly and break.
As a result, it is not necessary to inject high-pressure fluid toward the chips, and it is only necessary to devise the shape of the shim breaker. Can be more reliably broken. In addition, the chip breaker can be largely bent and broken without hitting the workpiece on the workpiece.

  Next, a second invention of the present invention is the shim breaker according to the first invention, wherein the direction of inclination of the guide surface with respect to the rake surface is substantially parallel to the direction in which chips extend during cutting. The direction of the guide surface is set so that

  In the second invention, the direction of the guide surface is set so that the direction of inclination of the guide surface with respect to the rake surface and the direction in which the chips extend during cutting are substantially parallel to each other. It is possible to guide to the protrusion. Moreover, since the angle which a chip | tip hits with respect to a protrusion part can be maintained at an appropriate angle, a chip | tip can be fractured | ruptured more reliably by a protrusion part.

In the first invention, the inclination angle of the guide surface is set in two stages, and the inclination angle of the second guide surface farther from the rake face than the inclination angle of the first guide face closer to the rake face is set. Is set to a larger inclination angle.
Due to the two-step inclination angle, chips generated continuously during cutting are first guided from the first guide surface to the second guide surface appropriately. And the chip | tip led to the 2nd guide surface is made into a suitable curved state so that it may be bent greatly by a protrusion part and it is easy to fracture | rupture, and is guide | induced to a protrusion part. And the chip | tip guide | induced to the protrusion part is bent largely by a protrusion part, and is fractured | ruptured.
Thus, by making the inclination angle of the guide surface into two stages, the chips can be more reliably broken at the protruding portion.

(A) is a top view explaining the example of the whole structure of the lathe provided with the shim breaker of this invention, (B) is a side view of the said lathe. It is a figure explaining the attachment state of a chip | tip and a shim breaker. It is a perspective view explaining the example of the external appearance of the guide surface of the shim breaker of 1st Embodiment, and the protrusion part in the state where the shim breaker of 1st Embodiment was attached to the rake face of the chip | tip. It is a perspective view explaining the example of the whole shape of the shim breaker of 1st Embodiment. In the shim breaker of 1st Embodiment, it is a figure explaining the relationship between the direction where the chip | tip extends when a workpiece | work is cut, and the inclination direction of the guide surface of a shim breaker. It is the figure which looked at FIG. 5 from the B direction, and is a figure explaining a mode that the chip | tip which generate | occur | produced continuously is fractured | ruptured by the protrusion part of a shim breaker. (A) is a perspective view explaining the external appearance of the shim breaker of the second embodiment, and (B) and (C) are the direction in which the chips extend when the workpiece is cut and the inclination direction of the guide surface of the shim breaker. It is a figure explaining a relationship. (A) is a perspective view explaining the example of the external appearance of the conventional shim breaker, (B) is a figure explaining the relationship between the direction where the chip | tip extends when cutting a workpiece | work, and the inclination direction of the guide surface of a shim breaker. (C) is a figure explaining the example in case the chip | tip which generate | occur | produced continuously is not fractured | ruptured.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. In each figure, when X axis, Y axis, and Z axis are described, the X axis, Y axis, and Z axis are orthogonal to each other, and are parallel to the workpiece rotation axis XJ that is the rotation axis of the workpiece W. Is the X-axis direction, the horizontal direction in which the cutting tool 50 is cut into the cylindrical surface of the workpiece W is the Z-axis direction, and the vertical upward direction is the Y-axis direction.

● [Overall configuration of lathe (Fig. 1) and mounting condition of chip and shim breaker (Fig. 2)]
As shown in the plan view of the lathe 1 shown in FIG. 1 (A) and the side view of the lathe 1 shown in FIG. 1 (B), the lathe 1 equipped with the shim breaker of the present invention includes a base 2, a headstock 40, a center It has a pedestal 46, an X-axis direction moving table 10, an X-axis direction driving means 10M, a Z-axis direction moving table 20, a Z-axis direction driving means 20M, a turret 30, a cutting tool 50, a control means 60, and the like. In addition, description of the tailstock 46 is abbreviate | omitted in FIG. 1 (B).
The headstock 40 is fixed on the base 2 and includes a main shaft 41.
The main shaft 41 includes a chuck 42 that can be driven to rotate around the workpiece rotation axis XJ based on a control signal from a control means 60 (for example, a numerical controller) and can grip and release the workpiece W.
The tailstock 46 is fixed on the base 2 and includes a center 47.
The center 47 is rotatably provided around the workpiece rotation axis XJ, is movable along the direction of the main shaft 41, and is urged in a direction toward the main shaft 41.
The workpiece W is, for example, a cylindrical member, is gripped by the chuck 42 of the main shaft 41, is pressed against and supported by the center 47 in the direction of the main shaft 41, and is rotated about the workpiece rotation axis XJ by the rotation of the main shaft 41. The

The X-axis direction moving table 10 reciprocates in the X-axis direction with respect to the base 2 along a guide rail 10 </ b> L provided along the X-axis direction on the base 2.
The X-axis direction driving unit 10M (for example, an electric motor) rotates a ball screw (not shown) based on a control signal from the control unit 60, and moves the X-axis direction moving table 10 connected to the ball screw to the X-axis. Move back and forth in the direction. The movement amount is controlled based on a detection signal from an encoder 10E provided in the X-axis direction driving unit 10M.
The Z-axis direction moving table 20 reciprocates in the Z-axis direction with respect to the X-axis direction moving table 10 along a guide rail 20L provided along the Z-axis direction on the X-axis direction moving table 10.
The Z-axis direction driving means 20M (for example, an electric motor) rotates a ball screw (not shown) based on a control signal from the control means 60, and moves the Z-axis direction moving table 20 connected to the ball screw to the Z-axis. Move back and forth in the direction. The movement amount is controlled based on a detection signal from an encoder 20E provided in the Z-axis direction driving unit 20M.

The turret 30 is fixed on the Z-axis direction moving table 20 and holds the cutting tool 50.
The cutting tool 50 is held by the turret 30 so that the contact point with the workpiece W is located on a virtual plane VM that is an XZ plane including the workpiece rotation axis XJ.
As described above, the control means 60 receives the detection signals from the encoders 10E and 20E, controls the main shaft 41 to rotate, controls the X-axis direction drive means 10M, and Z-axis direction drive. A control signal for driving the means 20M is output.

Next, the mounting state of the chip 53 and the shim breaker 54 will be described with reference to FIG.
A cutting tool 50 is fixed to the turret 30 together with the spacer 31 and the like.
The cutting tool 50 includes a holder 51, a shim 52, a chip 53, a shim breaker 54, a clamper 55, and the like.
The holder 51 is fixed to the turret 30, and a recess is formed at the tip, and a shim 52, a chip 53, and a shim breaker 54 are arranged in this recess from the bottom. It is fixed. The shim 52 and the chip 53 are firmly fixed inside with a bolt or the like.
The shim 52 is disposed between the holder 51 and the chip 53 and adjusts the protruding amount of the tip (cutting blade) of the chip 53.
The chip 53 is a cutting blade and is disposed between the shim 52 and the shim breaker 54 and is disposed so that a tip portion extending in the Z-axis direction (toward the workpiece W) protrudes by a predetermined amount.
The shim breaker 54 is disposed on the rake face of the chip 53 and is provided to break chips generated continuously when the workpiece W is cut with the chip 53 with an appropriate length.
The clamper 55 fixes a shim 52, a chip 53, and a shim breaker 54 disposed at the tip of the holder 51 to the tip of the holder 51.

● [Sim Breaker of First Embodiment (FIGS. 3 to 6)]
Next, the shim breaker 54 of the first embodiment will be described with reference to FIGS.
3 shows a perspective view of the chip 53 with the shim breaker 54 attached on the rake face 53A. FIG. 4 shows a perspective view of the appearance of the shim breaker 54. As shown in FIG.
FIG. 5 is a diagram (a diagram viewed from the Y-axis direction) illustrating how the chips WK extend when the workpiece W is cut by the chip 53, and FIG. 6 is a diagram of FIG. 5 viewed from the B direction. is there.

As shown in FIG. 3, the shim breaker 54 is attached to the rake face 53 </ b> A of the chip 53. As shown in the AA cross section, the edge portion of the chip 53 is formed in a concave shape, and the edge portion in contact with the workpiece W for cutting the workpiece W has an acute angle shape in the rotation direction of the workpiece. Is formed.
As shown in FIGS. 3 and 4, the shim breaker 54 includes a first guide surface 54 </ b> A, a second guide surface 54 </ b> B, and a protruding portion in order from the side near the rake face 53 </ b> A on the surface facing the workpiece W during cutting. 54C.
As shown in FIG. 6, the first guide surface 54A and the second guide surface 54B have predetermined inclination angles (θ1, θ2) with respect to the rake face 53A, respectively, and the chips WK are projected to the protruding portion 54C. Guide (lead).

Further, as shown in FIG. 5, the inclination direction DA of the first guide surface 54A and the second guide surface 54B with respect to the rake face 53A and the direction DK in which the chips WK extend during cutting are substantially parallel to each other. The directions of the first guide surface 54A and the second guide surface 54B are set. Therefore, as shown in FIG. 5, the directions of the first guide surface 54A and the second guide surface 54B are inclined with respect to the workpiece rotation axis XJ by an angle θa.
The “inclination direction DA of the first guide surface 54A and the second guide surface 54B with respect to the rake face 53A” refers to an object placed on the first guide face 54A when the rake face 53A is assumed to be a horizontal plane, and the second This is the direction in which the object placed on the guide surface 54B slides down. Since the angle θa is provided, in FIG. 5, the inclination direction DA and the direction DK in which the chips WK extend at the time of cutting are substantially parallel.
By setting this angle θa, the chips WK can be reliably guided to the protruding portion 54C. Further, in FIG. 5, when the chip WK strikes the projecting portion 54C obliquely, there is a possibility that the chip WK is not largely bent by the projecting portion 54C and does not break. However, in FIG. 5, the angle at which the chip WK strikes the protrusion 54 </ b> C can be set to an appropriate angle (in the case of FIG. 5, a substantially right angle), so that the chip WK is bent more reliably at the protrusion 54 </ b> C. The chip WK can be reliably broken (see FIG. 6) at the protrusion 54C.

Further, as shown in FIG. 6, the guide surface constituted by the first guide surface 54A and the second guide surface 54B has an inclination angle set in two stages.
The inclination angle of the first guide surface 54A that is the guide surface closer to the rake face 53A is set to the first inclination angle θ1 that is a relatively gentle inclination angle with respect to the rake face 53A.
Chips WK continuously generated during cutting by the first guide surface 54A having the first inclination angle θ1 are first appropriately set to have the second inclination angle θ2 on the first guide surface 54A having the first inclination angle θ1. It is guided to the second guide surface 54B.

The inclination angle of the second guide surface 54B, which is the guide surface far from the rake face 53A, is a relatively steep inclination angle (an inclination angle larger than the first inclination angle) with respect to the rake face 53A. θ2 is set.
Due to the second guide surface 54B having the second inclination angle θ2, the chips WK guided to the second guide surface 54B having the second inclination angle θ2 are appropriately bent so that the chips WK are largely bent by the protrusion 54C and easily broken. It will be in a state and will be guide | induced to the protrusion part 54C.

54 C of protrusion parts arrange | positioned in the position furthest from the rake face 53A are formed so that it may protrude in the convex direction to the side which goes to the workpiece | work W with respect to a guide surface (in this case, 2nd guide surface 54B adjacent). ing.
As shown in FIG. 6, the protrusion 54C is formed to protrude from the second guide surface 54B to the workpiece side by the protrusion amount D1, and the chips WK guided to the protrusion 54C are transferred to the workpiece W. Bending to the side of, and breaking. It should be noted that if the protrusion amount D1 is too small, the chips cannot be properly broken, and if the protrusion amount D1 is too large, the protrusion may break due to the stress of the hit chips, so the protrusion amount D1 is appropriate. Is set to a proper protruding amount.
The chip WK comes into contact with the projecting portion 54C at the contact point P, is largely bent toward the workpiece W, and is broken.

As described above, the shim breaker 54 according to the first embodiment has a simpler configuration and has an appropriate length without causing the chips WK continuously generated during cutting by the tip 53 to break against the workpiece W. Can be more reliably broken.
The shim breaker 54 of the first embodiment has a shape for cutting by moving the tip 53 relative to the workpiece W in the left direction (direction XL in FIG. 5) in the state shown in FIG. Yes, in the case of cutting by moving the tip 53 relative to the workpiece W in the right direction in FIG. 5, the angle θa in FIG. 5 is changed to match the direction in which the chips WK extend.

● [Sim breaker of the second embodiment (FIG. 7)]
As shown in FIG. 7B, the shim breaker 54 ′ of the second embodiment moves the tip 53 relatively to the left with respect to the workpiece W (direction XL in FIG. 7B). The tip 53 may be moved relative to the workpiece W in the right direction (direction XR in FIG. 7C) as shown in FIG.
As shown in FIG. 7A, the shim breaker 54 ′ of the second embodiment moves the chip 53 in the direction XL with respect to the shim breaker 54 of the first embodiment shown in FIG. First guide surface 54AL, second guide surface 54BL, protrusion 54CL for cutting, and first guide surface 54AR, second guide surface 54BR, and protrusion for cutting by moving the tip 53 in the direction XR 54CR is different in that it has surfaces in two directions.
Hereinafter, this difference will be mainly described.

FIG. 7B is a diagram for explaining a state in which the chip 53 is moved (relatively moved) in the direction XL.
In this case, the chips WK are guided from the first guide surface 54AL to the second guide surface 54BL, guided to the protruding portion 54CL, and are broken at the protruding portion 54CL.
Further, the first guide surface 54AL and the first guide surface 54AL and the second guide surface 54BL are inclined in parallel with each other so that the inclination direction DAL of the first guide surface 54AL and the second guide surface 54BL with respect to the rake face 53A is substantially parallel to the direction DKL in which the chips WK extend during cutting. The direction of the second guide surface 54BL is set. Accordingly, as shown in FIG. 7B, the directions of the first guide surface 54AL and the second guide surface 54BL are directed to be inclined by an angle θL with respect to the workpiece rotation axis XJ.
The “inclination direction DAL of the first guide surface 54AL and the second guide surface 54BL relative to the rake face 53A” refers to an object placed on the first guide face 54AL when the rake face 53A is assumed to be a horizontal plane, and the second This is the direction in which the object placed on the guide surface 54BL slides down. And since angle (theta) L is provided, in FIG.7 (B), the inclination direction DAL and the direction DKL where the chip | tip WK extends in the case of cutting become substantially parallel.
Further, the inclination angle of the first guide surface 54AL with respect to the rake face 53A is the same as that of the first embodiment (first inclination angle θ1 shown in FIG. 6), and the inclination angle of the second guide face 54BL with respect to the rake face 53A is also set. Since it is the same as that of the first embodiment (second inclination angle θ2 shown in FIG. 6), description thereof is omitted.

FIG. 7C is a diagram illustrating a state in which the chip 53 is moved (relatively moved) in the direction XR.
In this case, the chips WK are guided from the first guide surface 54AR to the second guide surface 54BR, guided to the protruding portion 54CR, and are broken at the protruding portion 54CR.
In addition, the first guide surface 54AR and the first guide surface 54AR and the inclined direction DAR of the first guide surface 54AR and the second guide surface 54BR with respect to the rake surface 53A and the direction DKR in which the chips WK extend during cutting are substantially parallel to each other. The direction of the second guide surface 54BR is set. Accordingly, as shown in FIG. 7C, the directions of the first guide surface 54AR and the second guide surface 54BR are inclined with respect to the workpiece rotation axis XJ by an angle θR.
The “inclination direction DAR of the first guide surface 54AR and the second guide surface 54BR with respect to the rake face 53A” refers to an object placed on the first guide surface 54AR when the rake face 53A is assumed to be a horizontal plane, and the second This is the direction in which the object placed on the guide surface 54BR slides down. And since angle (theta) R is provided, in FIG.7 (C), the inclination direction DAR and the direction DKR where the chip WK extends in the case of cutting become substantially parallel.
Further, the inclination angle of the first guide surface 54AR with respect to the rake face 53A is the same as that of the first embodiment (first inclination angle θ1 shown in FIG. 6), and the inclination angle of the second guide face 54BR with respect to the rake face 53A is also set. Since it is the same as that of the first embodiment (second inclination angle θ2 shown in FIG. 6), description thereof is omitted.

Various changes, additions, and deletions can be made to the structure, appearance, shape, and the like of the shim breakers 54 and 54 'of the present invention without departing from the spirit of the present invention.
In the description of the present embodiment, an example in which the guide surface is configured by two surfaces, the first guide surface having the first inclination angle θ1 and the second guide surface having the second inclination angle θ2, has been described. The guide surface may be configured by one guide surface having an inclination angle between the first inclination angle θ1 and the second inclination angle θ2.
In the example shown in FIGS. 5 and 7, the tilt direction DA (or tilt directions DAL, DAR) of the guide surfaces (first guide surface and second guide surface) and the direction DK (or direction DKL) in which the chips WK extend are included. , DKR) is explained so that the direction of the guide surface is inclined with respect to the workpiece rotation axis XJ so as to be substantially parallel to the DKR). It may be substantially parallel to the axis XJ (θa = 0 in FIG. 5 and θL = θR = 0 in FIGS. 7B and 7C).

DESCRIPTION OF SYMBOLS 1 Lathe 2 Base 10 X-axis direction moving table 10M X-axis direction driving means 20 Z-axis direction moving table 20M Z-axis direction driving means 30 Turret 40 Spindle table 41 Spindle 46 Tailstock 47 Center 50 Cutting tool 51 Holder 52 Shim 53 Tip 53A Rake face 54, 54 'Shim breakers 54A, 54AL, 54AR First guide face 54B, 54BL, 54BR Second guide face 54C, 54CL, 54CR Protrusion 55 Clamper 60 Control means DA, DAL, DAR (with respect to rake face) Guide face Inclination direction DK, DKL, DKR Direction in which chip WK extends XJ Work rotation axis θ1 First inclination angle θ2 Second inclination angle θa, θL, θR Guide surface angle with respect to work rotation axis W Work WK Chip

Claims (2)

In a shim breaker that is attached to a chip that is a cutting blade used for a lathe and breaks chips generated continuously when a workpiece is cut with the chip,
The shim breaker is
Attached to the rake face of the chip,
In the surface facing the workpiece, a guide surface is provided on the side close to the rake face, and a protrusion is provided on the side far from the rake face,
The guide surface has a predetermined inclination angle with respect to the rake surface and guides chips toward the protrusion,
The protruding portion is formed so as to protrude in a convex shape toward the workpiece with respect to the guide surface ,
The guide surface has a first guide surface provided on a side close to the rake surface, and a second guide surface provided on a side far from the rake surface,
The inclination angle of the second guide surface with respect to the rake surface is set to be larger than the inclination angle of the first guide surface with respect to the rake surface,
The second guide surface is inclined such that the side closer to the protruding portion is away from the work than the side closer to the first guide surface,
The first guide surface chip direction length, which is the length of the first guide surface in the direction in which chips extend during cutting, is the length of the second guide surface in the direction in which chips extend during cutting. Is set longer than the second guide surface chip direction length,
The protruding portion protrudes in an arcuate convex shape toward the workpiece when viewed from a direction parallel to the rotation axis of the workpiece,
Sim breaker. The shim breaker according to claim 1,
The direction of the guide surface is set so that the direction of inclination of the guide surface with respect to the rake surface and the direction in which chips extend during cutting are substantially parallel,
Sim breaker.

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