Patent Publication Number: US-2023158577-A1

Title: Anvil with curved passage for cutting tool

Description:
RELATED APPLICATION DATA 
     This application is a divisional of U.S. Pat. Application Serial No. 16/465,699 filed May 31, 2019, which is a §371 National Stage Application of PCT International Application No. PCT/EP2017/079574 filed Nov. 17, 2017 claiming priority to EP 16201718.0 filed Dec. 1, 2016. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to anvils for cutting tools and, more particularly, to such anvils having fluid passages therein. 
     BACKGROUND 
     Cutting tools for modem metal cutting and other machining operations typically include toolholders with replaceable cutting inserts. The cutting inserts are typically made of much harder materials, such as sintered, cemented carbide, than the toolholders. The cutting inserts are typically clamped in recesses provided in the toolholders for the cutting inserts. Often, an anvil (sometimes referred to as a shim) is provided in the recess between the bottom surface of the recess and the bottom surface of the cutting insert. One purpose for providing an anvil is to position the cutting edge(s) of the cutting insert relative to the toolholder in a desired fashion. 
     Because of high temperatures generated during cutting operations, it is often desirable to provide cooling and/or lubricating fluid near the cutting edge of the cutting insert. It is also often desirable to provide fluid for removing of chips generated at the workpiece by the cutting operation. One technique for providing fluid for cooling, lubricating, and/or flushing is to position a nozzle above the cutting edge so that fluid can be directed at the cutting edge. This arrangement is disadvantageous in that it requires additional equipment and is difficult to use in applications involving small tools or workpieces. It is also largely limited to turning applications where the tool is not rotating, and is difficult or impossible to use in applications such as milling operations. 
     Another technique for providing fluid for cooling, lubricating, and/or flushing is to direct fluid through passages in the toolholder and, in some instances, through passages in the cutting insert. EP2946857A1 shows a turning tool holder and cutting insert with an anvil having a passage extending therethrough for introducing fluid to the cutting edge. 
     It is desirable to provide an anvil for a cutting tool with a passage having a complex geometry to facilitate providing fluid through the anvil. It is also desirable to be able to produce such an anvil by a simple, accurate technique. 
     EP2946857A1, however, only provides a fluid passage through the anvil that is in a straight line. A passage having a straight line structure limits options available for providing fluid by the cutting edge. For example, in the event that the anvil is secured to the toolholder by a bolt or other structure extending through a hole in the anvil, the hole may make it impossible to provide a passage that extends along a straight line. Forming a passage that goes around the hole may require several manufacturing steps such as advanced drilling and/or blind plugging operations, adding to the cost of the cutting insert. 
     Summary 
     According to an aspect of the present disclosure, an anvil for a cutting tool includes an anvil body, wherein a curved passage extends from an inlet opening in the anvil body to an outlet opening in the anvil body. 
     A curved passage in an anvil provides options for providing fluid to cool and/or lubricate a cutting insert, and/or flush chips away from a workpiece that are not possible or are only possible via passages in the anvil having complex geometries when passages extend along straight lines. The anvil provides additional geometry options for providing a coolant/lubrication/flushing beam from below a cutting insert without advanced drilling or blind plugging operations. 
     The anvil itself is applicable to most cutting insert clamping systems. The anvil can be manufactured at different thicknesses, depending on what is most suitable for the cutting insert shape. The anvil can, if desired, extend fully through the cutting toolholder to the bottom surface of the toolholder. 
     The present disclosure relates generally to anvils for cutting tools and, more particularly, to such anvils having fluid passages therein. 
     According to another aspect of the disclosure, the anvil includes a top surface, a bottom surface, and a side surface between the top surface and the bottom surface, the side surface having at least three side surface portions and at least three corner portions, each corner portion of the at least three corner portions being disposed between respective pairs of side surface portions of the at least three side surface portions, at least one corner portion of the at least three corner portions including a surface that extends radially outward from a central axis of the anvil relative to extensions of a respective pair of side surface portions of the at least three side surface portions, the central axis extending between the top surface and the bottom surface. By providing such a structure, a limited portion of the top surface of the anvil can extend past a bottom surface of the cutting insert to define an exposed area and the outlet opening can be provided in the exposed area, facilitating directing fluid toward the cutting edge. 
     In accordance with yet another aspect of the disclosure, a method for making an anvil for a cutting tool includes forming an anvil body having a curved passage that extends from an inlet opening in the anvil body to an outlet opening in the anvil body. 
     The method provides options for providing fluid to cool and/or lubricate a cutting insert, and/or flush chips away from a workpiece that are not possible or are only possible via passages in anvils having complex geometries when passages extend along straight lines. The method provides additional geometry options for providing a coolant/lubrication/flushing beam from below a cutting insert without advanced drilling or blind plugging operations. 
     In accordance with still a further aspect, the anvil body can be formed via an additive manufacturing process. By forming an anvil via an additive manufacturing process, an anvil having a complex shape, particularly a complex interior geometry such as including a curved passage, can be formed. Moreover, such an anvil can be formed at minimal cost. 
     In accordance with yet another aspect, a cutting tool including an anvil as described is provided. 
     The foregoing summary, as well as the following detailed description of the embodiments, will be better understood when read in conjunction with the appended drawings. It should be understood that the embodiments depicted are not limited to the precise arrangements and instrumentalities shown. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 - 4    are a perspective, a top, a side, and a bottom view of an anvil according to an aspect of the present disclosure. 
         FIG.  5    is a perspective view of a cutting tool including an anvil according to an aspect of the present disclosure. 
         FIG.  6    is an enlarged view of a portion of  FIG.  5   . 
         FIG.  7    is a top view of the cutting tool including an anvil according to an aspect of the present disclosure. 
         FIG.  8    is an enlarged view of a portion of  FIG.  7   . 
         FIGS.  9 A and  9 B  are side views of anvils according to further aspects of the present disclosure. 
         FIG.  10    is a perspective view of an anvil according to another aspect of the present disclosure. 
         FIG.  11    is a perspective view of an anvil according to yet another aspect of the present disclosure. 
         FIGS.  12 - 14    are a perspective, top, and side view of an anvil according to still yet another aspect of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS.  1 - 4    show an anvil  21  for a cutting tool  23  of the type shown in  FIGS.  5 - 8   . The cutting tool  23  illustrated in  FIGS.  5 - 8    is a turning tool, however, the disclosure is not limited to turning tools and may be applicable to other tools that use anvils (also referred to as shims), such as rotating tools, such as milling tools. 
     As seen in  FIG.  5   , the cutting tool  23  has a tool body or toolholder  25  in which a recess  27  is provided. The recess  27  can include a bottom abutment surface  29 , and two side abutment surfaces  31  and  33 . A cutting insert  35  is mounted in the recess  27  on top of the anvil  21 . Typically, side supporting surfaces  37  and  39  of the cutting insert  35  abut the side abutment surfaces  31  and  33  of the recess  27 , and a bottom supporting surface  41  of the cutting insert abuts a top surface, also referred to as a top abutment surface,  43  ( FIG.  1   ) of the anvil  21 . Side surfaces, also referred to as side supporting surfaces,  45  and  47  of the anvil  21  typically abut the side abutment surfaces  31  and  33  of the recess, and a bottom surface, also referred to as a bottom supporting surface,  49  ( FIG.  4   ) of the anvil abuts the bottom abutment surface  29  of the recess  27 . 
     A clamp  51  is provided to clamp the cutting insert  35  in the recess  27 . The clamp  51  may also clamp the anvil  21  in the recess  27 . Alternatively, the anvil  21  may be clamped in the recess  27  by a clamping arrangement separate from the clamp  51  that clamps the cutting insert  35 . For example, the anvil  21  may be clamped in the recess  27  by a screw or bolt that extends through a central opening  53  in the anvil while the insert may be clamped by a separate clamp  51 , such as the cantilever clamping assembly shown. 
     As seen in  FIGS.  1 - 4   , the anvil  21  includes an anvil body  55 , and a curved passage  57  extends from an inlet opening  59  in the anvil body to an outlet opening  61  in the anvil body. In the embodiment shown in  FIGS.  1 - 4   , the curved passage  57  extends from an inlet opening  59  in the bottom surface  49  of the anvil  21  to an outlet opening  61  in the top surface  43  of the anvil. 
     The expression “curved passage” is expressly defined herein as referring to passages that are not straight over their length and is particularly to be contrasted to a passage made up only of one straight portion, or more than one connected straight portions. Ordinarily, a “curved passage” will have a mathematically continuous curvature, however, it may comprise plural discontinuous mathematically continuously curved components as shown in  FIGS.  9 A and  9 B , including plural curved components  57   a  and  57   b  that are adjacent to each other to form a curved passage  571  as shown in  FIG.  9 A  and plural curved components 57a′ and 57b′ that are separated by a straight component  57   c ′ to form a curved passage  572  as shown in  FIG.  9 B . 
     A “curved passage” will transit sufficiently smoothly to provide minimal risk for clogging and/or significant pressure drop. The cross-sectional area of the passages may change, typically becoming smaller as the passage transits from its inlet opening(s)  59  to its outlet opening(s)  61 . The inlet opening  59  of the curved passage  57  will typically connect to a passage (not shown) in the toolholder  25  or elsewhere so that fluid can enter the passage and pass to the outlet opening  61 , usually for flushing chips from the cutting edge of the cutting insert  35  and/or for cooling the cutting edge. 
     In addition to or instead of having a curved passage that extends from an inlet opening in the bottom surface  49  of the anvil  21 ′ to an outlet opening in the top surface  43  of the anvil, the curved passage  57 ′ may extend from an inlet opening  59 ′ in the side surface  45 ′ and/or  47 ′ of the anvil as seen in  FIG.  10   . In addition to or instead of having a curved passage that extends from an inlet opening in the bottom surface  49  of the anvil  21 ″ to an outlet opening in the top surface  43  of the anvil, the curved passage  57 ″ may extend to an outlet opening  61   a ″ or  61   b ″ in the side surface  75 ″ and/or  77 ″ of the anvil as seen in  FIG.  11   . In addition to the anvil  21  having one or more curved passages, the anvil may also include one or more straight passages (not shown). 
     As seen in  FIGS.  1 - 4   , the passage  57  can have at least two branches. The anvil  21  includes the central hole  53 , the passage  57  includes plural branches  63  and  65 , and the inlet opening  59  includes plural inlet openings  69  and  71 , respectively. The first inlet opening  69   of the first branch  63  is disposed on a first side of the central hole  53 , and the second inlet opening  71  of the second branch  65  is disposed on a second side of the central hole opposite from the first branch. 
     If desired, one or more inlet openings (not shown) may be provided in the central hole so that fluid can flow through the central hole into the inlet openings and then through the curved passage. 
     In the anvil  21 ′ shown in  FIG.  10   , the passage  57 ′ includes plural branches  63 ′ and  65 ′, and the inlet opening  59 ′ includes plural inlet openings  69 ′ and  71 ′. The first inlet opening  69 ′ of the first branch  63 ′ is disposed in a first side surface  45 ′ of the anvil, and the second inlet opening  71 ′ of the second branch  65 ′ is disposed in a second side surface  47 ′ of the anvil different from the first side surface. 
     To illustrate the variety of curved passage configurations possible, in the anvil  21 ″ shown in  FIG.  11   , the passage  57 ″ includes plural branches  63 ″,  65 ″, and  67 ″, and the inlet opening  59 ″ includes plural inlet openings  69 ″,  71 ″, and  73 ″. The first inlet opening  69 ″ of the first branch  63 ″ is disposed in the side surface  45 ″ of the anvil, and the second inlet opening  71 ″ of the second branch  65 ″ is disposed in the bottom surface  49 ″ of the anvil, and the third inlet opening  73 ″ of the third branch  67 ″ is disposed in the side surface  47 ″. 
     The outlet openings  61   a ″ and  61   b ″ are disposed in the side surfaces  75 ″ and  77 ″ (considering portions of the corner portion  85 ″ to be part of these side surfaces), respectively, however, they might alternatively or additionally be disposed in the top surface  43 ″. There may be a different number of outlet openings than inlet openings, and there may be more outlet openings than inlet openings or vice versa. The outlet opening(s) will ordinarily be disposed in at least one of the side surface and the top surface and the inlet opening(s) will ordinarily be disposed in at least one of the bottom surface and the side surface, however, an outlet opening might be disposed in the bottom surface and an inlet opening might be disposed in a top surface. 
     Referring, for purposes of discussion, to  FIG.  1   , it will be seen that the anvil  21  can have plural side surfaces  45  and  47 . Typically, an anvil with plural side surfaces will have at least three side surfaces defined by corners or corner portions, i.e., will be substantially triangular, or will have more sides, such as the four sides illustrated in the anvil of  FIG.  1   . In the anvil  21 , there are four straight side surfaces  45 ,  47 ,  75 , and  77  and four corner portions  79 ,  81 ,  83 , and  85  disposed between pairs of the side surface portions. At least one corner portion  85  of the at least three corner portions includes a surface  87  that extends radially outward from a central axis CA ( FIG.  1   ) of the anvil  21  relative to extensions of the pair of side surface portions  75  and  77  separated by the corner portion  85 , the central axis extending between the top surface and the bottom surface. 
     By “extensions of the pair of side surface portions  75  and  77 ” it is intended to refer to the surfaces that would be defined if the side surface portions  75  and  77  were extended beyond where they are shown as ending and the corner portion  85  starts in  FIG.  2   , and illustrated by two dashed, straight lines E75 and E77 therein. The dashed, straight lines may intersect within the periphery of the anvil. By providing the corner portion  85  with the surface portion  87  that extends outwardly in this fashion, a portion of the top surface  43  of the anvil  21  can extend beyond the bottom supporting surface  41  of the cutting insert  35  as shown in  FIGS.  5 - 8   . The outlet opening  61  can be provided in this portion of the top surface  43  to facilitate providing cooling/flushing fluid to the cutting edge above the cover portion  85 . 
       FIGS.  12 - 14    show an anvil  121  according to another aspect of the disclosure in which an intermediate surface  200  is provided on a protruding corner  185  of the anvil. An outlet opening  161  can be provided in the intermediate surface  200 . Inlet openings (not shown) and other outlet openings (not shown) can be provided in any other surfaces as desired. The intermediate surface  200  is disposed below the top surface  143  and above the bottom surface  149 , although the intermediate surface may extend to the top surface and/or the bottom surface. 
     As illustrated, a plane of the intermediate surface  200  is parallel to a plane of the top surface  143  and a plane of the bottom surface  149  ( FIG.  3   ), however, the intermediate surface may form a non-zero angle with planes of the top or bottom surfaces and/or may be curved. Providing an intermediate surface  200  in which an outlet opening  161  can be provided between the top and bottom surfaces  143  and  149  and, more particularly, below the top surface, can facilitate providing workpiece clearance when the anvil  121  is used with thinner cutting inserts, negative inserts, or toolholders with small rake and/or inclination angles. The surface  187  of the protruding corner  185  may be at the same inclination angle as the rest of the side surface(s) of the anvil at a different inclination angle from some or all of the rest of the side surface(s) of the anvil. 
     Tool life generally increases with increase in coolant supply pressure. This can be attributed to the ability of the high-pressure coolant to lift the chip and gain access closer to the cutting interface. This action leads to a reduction of the seizure region, thus lowering the friction coefficient, which in turn results in reduction in cutting temperature and cutting forces. The pressure used in the discussed embodiments is above 30 bar, for example, above 100 bar coolant pressure. 
     In another aspect of the disclosure, a method for making an anvil  21  for a cutting tool  23  includes forming an anvil body  55  having a curved passage  57  that extends from an inlet opening  59  in the anvil body to an outlet opening  61  in the anvil body. The anvil body  55  can be formed via any suitable one of a plurality of different additive manufacturing processes such as metal 3D printing processes that use binders, or fully dense metal processes such as selective laser sintering (SLS) or direct metal laser sintering (DMLS). DMLS technology, for example, uses a high power laser to fuse small particles of metal powders into a shim or anvil that has a desired three dimensional shape. A laser beam “draws” directly on the powder so that only selected portions of the powder are solidified. The powder is said to be “scanned” by the laser. The use of a laser in this manner allows layers of different shape to be easily and rapidly fused, enabling complex objects with intricate internal structures to be produced. The laser selectively fuses the powdered metal by scanning the cross-sections (or layers) generated by a three dimensional modeling program on the surface of a powder bed. 
     After each cross-section is scanned, the powder bed is lowered by one layer thickness. Then a new layer of material is applied on top and the process is repeated until the shim is completed. Such a process makes it possible to produce complex anvils with shapes such as curved passages. Thus, the curved passage exhibits a continuous course, which is optimized from the point of view of flow engineering and which can be produced, for example, by means of an additive manufacturing process. Machining subsequent to additive manufacturing may also be performed. 
     In the present application, the use of terms such as “including” is open-ended and is intended to have the same meaning as terms such as “comprising” and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as “can” or “may” is intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such. 
     The curved passage is to be distinguished from a groove or a curved groove in a surface of the anvil. The curved passage is curved along its length, and is tubular in that the wall or walls of the curved passage extend entirely around a longitudinal axis of the passage. 
     Although the present embodiment(s) has been described in relation to particular aspects thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred therefore, that the present embodiment(s) be limited not by the specific disclosure herein, but only by the appended claims.