CN111050952A - Cutting tool pressing method and apparatus - Google Patents

Abstract

The present invention relates to a method of manufacturing a cutting tool, in particular a milling cutter, such as an end mill. The method includes providing one or two part molds. In one embodiment, two mold units are used, each mold unit comprising two openings. According to this embodiment, the method comprises: connecting two mold units to form a mold; and inserting at least one pressing punch through one of the remaining openings to press the metal, ceramic or carbide powder added to the die. The pressed cutting tool can be ejected by a rotating ejector rod which pushes the cutting tool out of the die by a rotational translational movement. The invention also relates to a device for implementing said method.

Description

Cutting tool pressing method and apparatus

Technical Field

The present invention relates to a method of manufacturing a cutting tool, a precursor cutting tool, a blank and/or a cutting tool insert, to a cutting tool, a precursor, a blank and an insert obtained by said method, and to an apparatus for carrying out said method.

Background

Cutting tools such as end mills are typically manufactured by feeding a particulate material such as metal and/or carbide powder into an extruder to compact and extrude rods, hydrogen de-waxing, sintering, cutting, centerless grinding, groove grinding and coating. Different manufacturers may perform different steps. The dewaxing step is typically carried out in a hydrogen furnace and sintering in a HIP (hot isostatic pressing) furnace. In some cases, the grooves are honed prior to cleaning and coating.

The cutting edge or the groove of the cutting tool is formed in the step of grinding the bar to obtain the groove of a desired shape.

Only few manufacturers have equipment for producing so-called blanks, which are extruded cemented carbide rods that have been cut to the correct length and centerless ground to change their diameter. Small and medium companies can purchase blanks for grinding processes and coatings. This can be achieved by a groove grinder that can grind out grooves to obtain a specific geometry.

The above-described production of particularly radiused cutting tools presents several disadvantages and limitations. The step of grinding the grooves into the extrusion stem or blank results in a large amount of scrap material because much of the material is cut from the extrusion stem when cutting the grooves or other cutting edges of the cutting tool. In other words, a lot of raw material is lost due to grinding the groove in the cutting tool. Although the spent carbide can be filtered and reused, it would be advantageous to reduce the amount of waste material in the grinding process.

In addition, the groove grinding process is typically a slow process performed on a relatively expensive grinding machine. Therefore, grinding the grooves requires a large capital investment and the machining cost is high. It would be advantageous to reduce the costs associated with the grinding step.

The energy consumption of the whole process from extrusion to production of the final product is very high. It is an object of the present invention to reduce the energy costs associated with the production of cutting tools.

The object of the invention is to reduce the time, cost and energy consumption of the manufacturing process by reducing the grinding time of the grooves and the loss of material due to grinding.

The object of the invention is to produce a blank which already has the desired length and diameter and has already finished grooves or already pre-grooves or near finished grooves so that only the necessary final grinding is necessary to obtain the desired geometry of the finished product. From the above it is clear that small and medium companies need such near-finished tools, which do not produce blanks themselves.

In the prior art, it has been proposed to produce cutting tools by some type of moulding process. For example, US2010/0090362 discloses an apparatus using a bag made of elastic material, the bag comprising a mould of cutting tools. After filling the bag with powder, it is transferred to a pressure sleeve connected to an isostatic press using a high pressure liquid. The pressurized liquid applies a generally uniform compressive load to the outer surface of the elastic die, thereby pressurizing the powder within the pocket. The method appears to involve several steps, some of which must be performed manually, such as securing the top and bottom caps to the bag, transferring the bag to a filling sleeve, and transferring the bag to a pressurizing sleeve. Secondly, US2010/0090362 does not disclose how to obtain a cutting tool comprising a spiral or thread groove using said method.

FR2078131 discloses an apparatus for compacting a helical or threaded pinion using metal powder. The apparatus uses two opposing punches having helical profiles that can be matched to the helical shape of a die having internal threads. After filling the die with the metal powder, the pinion is pressed by rotating the punch while the punch enters the die from the top end and the bottom end, thereby pressing the pinion with a thread. Although this method may be suitable for obtaining a pinion featuring an integral helical external thread, said method is not suitable for cutting tools. In particular, this document does not disclose how to obtain a cutting tool, such as an end mill, which requires a non-helical, generally cylindrical shank for holding and positioning the cutting tool in a tool holder.

JP H08260006A relates to a method of manufacturing a drill bit by displacing a first rotary punch in a mould cavity, wherein the mould cavity comprises a shank portion and a groove portion of the drill bit. The method suggests to spray film former onto the compressed preform during extraction to prevent the preform from collapsing during extraction from the mold cavity.

US 2016/0229082 discloses a press for manufacturing cutting tool green bodies using a die having helical projections and two simultaneously rotating electric punches for pressing the green bodies. This document solves the problem of providing a press with two rotating screw punches. According to the present disclosure, it is not possible to manufacture an end mill comprising a shank and a helical region by pressing.

US 2012/0003443 discloses a split box die for producing cutting inserts. This document does not disclose how to produce an end mill or drill, but teaches separating the mold parts in a direction non-parallel to the pressing axis to release the parts.

The present invention solves the above problems.

Disclosure of Invention

Notably, the present inventors provide a method of producing a cutting tool by pressing, for example, by die pressing.

In one aspect, the present invention provides a method of making a cutting tool, a blank tool and/or a precursor cutting tool, the method comprising the steps of: providing a mold, wherein the mold comprises a first opening and a second opening; filling the mould with a suitable powder or granules; applying pressure to the powder, thereby obtaining a pressed cutting tool, a blank tool and/or a precursor cutting tool.

In one aspect, the method comprises providing a first and a second mould unit, connecting the two mould units to obtain a continuous mould of the tool to be manufactured, filling the mould with powder or granules, and pressing the powder or granules into the mould so as to obtain a pressed cutting tool.

In one aspect, the present invention provides a method of making a cutting tool, a blank tool and/or a precursor cutting tool, the method comprising the steps of: providing a first mold unit and a second mold unit, wherein the first mold unit comprises a first mold part or region, wherein the second mold unit comprises a second mold part or region; filling carbide, ceramic or metal powder into the first and second mold units; applying pressure to the powder, thereby obtaining a pressed cutting tool, a blank tool and/or a precursor cutting tool.

In one aspect, the present invention provides a method of making a cutting tool, a blank tool and/or a precursor cutting tool, the method comprising the steps of: providing a first mould unit and a second mould unit, wherein the first mould unit comprises a first mould part or region defining at least a part of a shank of a tool to be manufactured, wherein the second mould unit comprises a second mould part or region comprising a ridge designed to define a recess of the tool to be manufactured, and wherein the first and second mould units each comprise a first opening; making up a mold from the first mold unit and a second mold unit by bringing a first opening of the first mold unit into contact with a first opening of the second mold unit; filling a powdered composition comprising carbide, ceramic, metal, nitride or cermet powders, or powders comprising one, two or more of the foregoing mixtures into the first and second mold units; applying pressure to the powdered composition, thereby obtaining a pressed cutting tool, a green tool, and/or a precursor cutting tool.

In one aspect, the invention provides an apparatus for carrying out the method of the invention. Preferably, the apparatus of the present invention is used to manufacture cutting tools, blank tools and/or precursor cutting tools.

In one aspect, the apparatus of the present invention comprises a first mould unit comprising a first mould part of a tool to be manufactured; a second mould unit comprising a second mould part of the tool to be manufactured; at least one pressing device arranged to be inserted through an opening of the first and/or second mould unit and to press the powder remaining in the mould.

In one aspect, the present invention provides an apparatus for manufacturing a cutting tool, a blank tool and/or a precursor cutting tool, the apparatus comprising: a first mould unit comprising a section having a first mould portion or region defining at least a portion of a shank of a tool to be manufactured; a second mould unit comprising a second mould part comprising a ridge designed to define a groove of a tool to be manufactured; at least one pressing device arranged to be inserted through an opening of the first and/or second mould unit and arranged to move coaxially with the axis of the mould formed by the mould unit connection for pressing the powder remaining in the mould.

Other aspects and preferred embodiments of the invention are defined hereinafter and in the appended claims.

Other features and advantages of the present invention will become apparent to the skilled person from the description of preferred embodiments given below.

Drawings

Fig. 1 shows an apparatus according to an embodiment of the invention.

FIG. 2A illustrates various exemplary components of a device according to an embodiment of the invention.

Fig. 2B shows an exemplary cutting tool obtainable by the method of the present invention.

Fig. 3A and 3B show the empty and powder-filled filling hoppers, respectively, of the apparatus of fig. 1.

Fig. 4A and 4B show longitudinal sections of the die unit and punch of fig. 2 arranged at an earlier stage of the method of an embodiment of the invention.

Fig. 5 is an enlarged view of the mold unit of fig. 4B filled with powder.

Fig. 6A, 6B and 6C illustrate a pressing process of the cutting tool according to the embodiment of the present invention.

Fig. 7 and 8 illustrate a process of removing a pressed cutting tool from a die after pressing the cutting tool according to an embodiment of the present invention.

Fig. 9 illustrates a knockout process of a pressed cutting tool according to an embodiment of the present invention.

Fig. 10A and 10B illustrate a method and apparatus according to a second embodiment of the invention, in which different punches are used to apply pressure to the powder in the die.

Detailed Description

The present invention relates to a method of manufacturing a cutting tool and to an apparatus or machine for carrying out the method.

The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

For the purposes of this specification, the term "including" and its various grammatical forms are intended to mean "including, but not limited to. It is not intended to mean "consisting only of.

Fig. 1 shows an apparatus 100 according to an embodiment of the invention. The apparatus comprises a support, mount or frame 60 on which the die units 4, 5 and the press punches 12, 13 are supported. The apparatus 100 comprises a displacement and positioning device 90 configured to displaceably support one or more parts of the apparatus relative to the frame 60. In one embodiment, one or more of the first mold unit 4, the second mold unit 5, and the fill container 40 are movably positioned by a positioning device 90. In the embodiment shown, the first or lower die unit 4 is preferably arranged so as to be movable along the axis of movement of the punch, shown vertically in the figures, and optionally also horizontally. To ensure that certain parts of the apparatus are displaceable, the positioning device 90 may comprise guide structures or rails 91, 92, 93 on which certain parts or elements are displaceably arranged.

In the illustrated embodiment, the positioning device 90 includes a first rail or guide 94 that includes a first rail 91. The first guiding means 94 allow the mould unit, here the first mould part 4, to be displaced along the first axis, here the vertical axis 27 (see fig. 2A).

In the illustrated embodiment, the positioning device 90 includes a second rail or guide device 95 that includes a second rail or guide structure 92 that allows the mold unit (here, the second mold unit 5) to be displaced along a second axis (here, a horizontal axis perpendicular to the first axis 27).

In the illustrated embodiment, the positioning device 90 includes a third track or guide 96 that includes a third track or guide structure 93 that allows the powder-filled container or funnel 40 to be displaced, preferably along a third axis. The filling container is preferably arranged displaceable along a horizontal axis, e.g. perpendicular to said first and/or second axis.

For the purposes of this specification, the terms "first," "second," and "third" are not necessarily used to imply order or importance, but are used to distinguish structural elements, some of which may be optional. For example, any one, two, or all three of the first, second, and third guides 94-96 may not be present. For example, the above-mentioned second guiding means 95 may be the first and/or the only guiding means. Preferably, at least one mould unit and/or filling container 40 is displaceably arranged.

It should also be noted that the guide shown is configured to allow displacement along a straight, linear axis. In other embodiments, the present invention includes a guide arrangement that allows one or more of the mold units 4, 5 and other structural components (e.g., the fill container 40) to be displaced along a non-linear axis.

The first and second pressing punches 12, 13 are preferably displaceably arranged on the apparatus 60. The press ram is preferably configured to be movable along a common axis 27 (fig. 2A). Preferably, in the invention of the present invention, the pressing punches 12, 13 are coaxially arranged and coaxially movable along a common axis.

The apparatus 100 of the present invention preferably includes first and second punch holders or retainers 81, 82 in which the pressurized punches are secured. The apparatus preferably comprises a pressure generator (not shown) which allows the punches 12, 13 to move while applying pressure, or to be displaced against a certain counter pressure. Preferably, the pressure and counter-pressure exerted by the punches 12, 13 can be adjusted.

The apparatus of the invention preferably comprises a data processing unit (not shown), such as a computer, for controlling and implementing the method of the invention. The data processing unit may be used to configure the method steps to control the time, speed and sequence of movement of the apparatus structural parts and the amount of pressure applied, for example, as well as the activity of the powder compaction entity (e.g. an ultrasonic generator).

In the illustrated embodiment, the structural components of the device are arranged to have an overall vertical mode of operation. The punches 12, 13 are coaxial along a vertical axis and the die portions 4, 5 are stacked vertically one above the other. The vertical arrangement may provide some advantages, for example, allowing filling of the die by gravity and facilitating adjustment and alignment of structural components such as the die unit and punch. However, the present invention is not meant to be limited to such an overall vertical arrangement. Parts such as punches and dies may also be aligned on another axis, for example, relative to a horizontal axis or even an offset axis, without departing from the concept of the invention. Preferably, the die and punch are configured to be coaxially disposed.

The apparatus of the invention preferably comprises propulsion means for actively propelling the movement of certain movable parts, such as electric motors, actuators, which may comprise, for example, electric motors or actuators, pneumatic and hydraulic actuators, etc.

Fig. 2A and 2B illustrate components of an apparatus for practicing the method of the present invention and an exemplary cutting tool 20 that may be manufactured by the method of the present invention.

For the purposes of this specification, the term "cutting tool" is used to refer to any one or all of a cutting tool, a blank tool, a cutting tool blank, and/or a precursor cutting tool. For example, a "cutting tool" may be referred to as a cutting tool blank. As mentioned in the introduction, a cutting tool prepared for commercialization may undergo various steps such as hydrogen dewaxing, sintering, cutting, centerless grinding, groove grinding, honing, cleaning, and coating. These known steps are not described in detail in this specification, but are also included as optional further or supplemental processing steps of the invention. For the purposes of this specification, a "cutting tool" is a product obtained by the method disclosed in this specification, optionally further processed in preparation for commercialization.

In one embodiment, the cutting tool is selected from the group consisting of an insert and a solid radius tool. Solid radius tools include solid end mills, reamers, drills, and thread mills.

In a preferred embodiment, the cutting tool 20 is a milling cutter, preferably an end mill. Preferably, the cutting tool is longitudinal, so it is longer or not larger. It preferably has a longitudinal axis 23.

In a preferred embodiment, the cutting tool, blank tool and/or precursor cutting tool 20 is a solid radius tool, a blank solid radius tool and/or a precursor solid radius tool, preferably an end mill, a blank end mill or a precursor end mill, more preferably a solid end mill, a solid blank end mill or a solid precursor end mill.

The cutting tool 20 shown in fig. 2B has a generally substantially rod-like configuration. Due to its longitudinal rod-like configuration, the cutting tool 20 has two ends, as shown in FIG. 2B, corresponding to the bottom and top ends of the tool 20. Furthermore, the cutting tool preferably comprises two parts or sections, in particular two bar sections 1, 2, which cover at least the first and second ends of the cutting tool. The first shank segment 1 preferably comprises at least a first end of a cutting tool. The first shank segment 1 preferably defines or comprises a shank of a cutting tool. The two ends are preferably present at two opposite sides of the cutting tool. When the cutting tool is used, it is preferably placed in a cutting tool holder at the shank 1 and rotated.

The second shank segment 2 preferably comprises at least a second end of the cutting tool. The second rod section preferably comprises a groove and/or a flank 10. The recess and/or shoulder preferably determines the geometry of the cutting portion of the tool and thus generally helps to define at least part of the cutting performance of the cutting tool. The groove 10 at the second shank segment 2 allows cutting of a suitable material by means of a rotary cutting tool 20.

In a preferred embodiment, the groove is a helical groove, for example a spiral groove.

Furthermore, the cutting tool may comprise additional surface structures that are typically used for cutting tools. Such additional structures may for example be integrated into the spiral groove portion 2 on the surface of the spiral groove portion 2.

The cutting tool preferably comprises and/or consists essentially of a hard material such as metal, ceramic and/or carbide. In a preferred embodiment, the cutting tool comprises or consists essentially of tungsten carbide. For example, the cutting tool comprises at least 50 wt.%, preferably at least 70 wt.%, more preferably at least 90 wt.% of a metal, cermet, ceramic, nitride or carbide, preferably tungsten carbide.

For purposes of illustration in fig. 2A, some components of the apparatus 100 of the present invention are arbitrarily arranged. The apparatus comprises in particular a first mould unit 4 and a second mould unit 5, both in the longitudinal section shown in fig. 2A.

The mould units 4, 5 are parts which preferably comprise mould parts or zones 14, 15, i.e. parts shaped as a negative mould or template 14, 15 for the cutting tool 20 to be manufactured.

As can be seen in fig. 2A, the first mould unit 4 may be provided in the form of a single piece 4 comprising a longitudinal bore 24. Thereby forming a first opening 6 and a second opening 8 in the mould unit 4. As will be more clearly seen from the description of the specification, the die portion or section 14 of the bore 24 comprises a negative die or die region 14 of a portion of the cutting tool to be manufactured. Preferably, the first die region 14 provides a negative die of the shank 2 of the cutting tool 20 to be manufactured. The bore 24 is preferably a cylindrical bore having a straight axis 27.

In one embodiment, the conduit 24 and the region 14 have the shape of a straight hollow cylinder with a constant cross-section along the axis 27 of the conduit. The first opening 6 and the second opening 8 are provided at a first end and a second end or end of the duct 24.

The conduit 24 defines the first mould region 14 at the first opening 6 and in the vicinity of the first opening 6. The tube forms a punch entry opening for the first punch 12 at the second opening 8. At said opening, the hole 24 preferably has the purpose of guiding the first punch 12 during the pressing operation.

In a preferred embodiment, the mold region 14 and/or the entire aperture 24 includes a smooth, regular, and/or unstructured surface. Preferably, the mold region 14 is substantially free of structures and/or raised structures that may appear from the inner surface of the liner defining the mold region 14 and/or the conduit 24. Preferably, the conduit 24 is free of internal threads and/or ridges. Preferably, the mold region 14 is free of helical ridges. The presence of the ridge will imply a change in the shape and/or profile of the cross-section of the mold region or cavity 14 due to the presence of the ridge along the longitudinal axis 27. As described elsewhere in this specification, smooth surfaces and the absence of protruding structures are preferred to facilitate entry of the first press punch and to allow removal of the first die 4 by translational movement along axis 27. The above does not exclude the possibility that the duct 24 comprises areas of different diameter. For example, the diameter at region 14 may be different, e.g., smaller or larger, than the diameter of the conduit 24 at the punch entry port 8.

Preferably, the cross-section of the bore 24 is a circle with a constant radius along the axis 27, so that the bore 24 in the first die 4 has a hollow cylindrical shape. Preferably, the aperture 24 is tubular. The present invention does not exclude that the duct 24 has another cross-section, for example a polygonal shape (e.g. rectangular, hexagonal, etc.). Thus, the cavity 24 formed by the first mold 4 may have the shape of a prism, for example.

Note that the expressions duct, bore, chamber and mould are used with reference to the blank areas marked with reference numerals 24, 25 and 26. Different terms are used to emphasize different functional and/or geometric features of the space in question. For example, the term conduit and/or bore may be used to indicate the continuous nature of the blank spaces on the exemplary mold units 4 and 5, the term "chamber" generally denoting the fact that a defined blank space is provided, and the term "mold" generally denoting that at least a portion of the blank space provides a mold or negative for the cutting tool to be prepared.

The apparatus of the present invention preferably comprises a second mould unit 5. In the embodiment shown, the second mould unit 5 is a mould part assembly. The second mold unit 5 preferably includes an insert 50 that is secured or received in the mold securing member 43. Insert 50 preferably comprises a negative or mold region 15 of a portion of a cutting tool to be manufactured. Preferably, the second mould region 15 provides a negative of the recess portion 2 of the cutting tool 20 to be manufactured.

The insert 50 includes a longitudinal conduit 28, the walls of the longitudinal conduit 28 defining a mold region 15 of a portion of a cutting tool to be manufactured. In this regard, the liner or surface forming the conduit 28 preferably includes ridges 3, the ridges 3 designed to define the grooves 10 of the cutting tool to be manufactured.

In a preferred embodiment said ridge 3 in the die area 15 is a helical, preferably spiral ridge, providing a negative die or die for the helical groove 10 on the cutting tool.

According to one embodiment, the ridges 3 in the second die region 15 may be compared to, similar to, or may be provided along the grain of the straight internal thread, thereby providing a concave portion to the straight external thread in the second section 2 of the cutting tool 20 in order to be pressurized. Although the expressions internal and external threads may be used in this description, these terms are not intended to exclude that the flutes of the cutting tool generally have more complex shapes, which are not necessarily symmetrical, and which help to define the cutting geometry and/or cutting characteristics of the cutting tool 20.

In one embodiment, the ridge 3 comprises and/or provides a straight internal thread provided in the longitudinal duct 28 of the second mould unit, in particular in the longitudinal duct 28 of the insert 50.

The insert 50 may be fixed in the housing 26, and the housing 26 may be in the form of a hole provided in said holder 43, said hole 26 preferably being such that the longitudinal mould 15 is coaxially positioned with respect to the mould region 14 of the first mould unit 4. The insert 50 can be rigidly but removably fixed with respect to the holder 43 by means of a screw (not shown) extending in a hole 29 provided in said member 43, said hole 29 preferably having an internal thread.

One advantage of providing the second mould part 15 in the form of an insert 50 of the mould unit 5 is that it allows the same holder 43 to be used for manufacturing cutting tools having different recesses 10. An operator may simply replace a particular insert 50 with another insert whose mold region 15 defines a different recess 10 pattern. Furthermore, given that the mould region 15 is subjected to wear in the method of the invention, it is possible to replace the new mould region quickly and with little cost.

Note that the housing 26 may be provided in the form of a cylindrical hole, but may also be provided in the form of a hollow, uniform prism (e.g., having a polygonal cross section). A non-circular housing that mates with a corresponding non-circular outer side of the insert 50 may help prevent rotation of the insert 50 in the method of the present invention.

In the illustrated embodiment, the piece 43 holding the mold insert 50 comprises another insert or second insert 36 comprising a longitudinal bore or conduit 25. The members 50 and 36 are preferably coaxially fixed in said member 43, in particular in a longitudinal hole or bore 26 provided in said member 43. More specifically, the inserts 50 and 36 are fixed relative to the piece 43 such that the bore 25 in the piece 36 is coaxial with and aligned with the longitudinal mold region 15 in the insert 50. Preferably, insert 36 is also removably secured to mold fixture 43. In this manner, the insert 36 can be replaced and replaced as necessary.

It should be noted that a mold component assembly 5 including only one insert 50 may be provided such that the conduit 25 is disposed directly in the piece 43, rather than being provided by a separate insert 36. Furthermore, the entire assembly 5 may be provided in a single piece.

Preferably, the second die unit 5 comprises a continuous conduit 25, 28 comprising the second opening or punch entry region 9 and the conduit 28 in the insert 50. The punch entry 9 of the tube 25 and the tube 28 at the second die area 15 are preferably coaxial, so that one single, preferably straight tube 25, 28 is formed.

The insert 50 is preferably received as follows: the conduit 28 of the insert 50 is coaxial with the conduit 25 of the piece 36 and forms one continuous conduit 25, 28 with the conduit 25 of the piece 36. The second opening 16 of the insert 50 is thus formed by the terminal opening of the tube 28 of the insert 50. The first opening 7 of the insert 50 is preferably provided and coincides with the first opening 7 of the second mould unit 5.

For the purposes of the present invention, the separate mould unit 4 on the one hand and the separate mould unit 5 on the other hand, which two mould units each comprise a respective mould area 14, 15, can be provided separately in one piece. Or provided as an assembly, such as the assembly 43, 50, 36 of the second mould unit 5.

In another embodiment according to this aspect, in which only one mould or one mould assembly is used instead of two separate mould units 4, 5, the mould assembly may also be in the form of a single piece or an assembly comprising a plurality of pieces, which are rigidly connected but detachable.

Thus, a unit or assembly comprising one of the two mould parts may be referred to as a "mould assembly", irrespective of the number of separate pieces used to construct the apparatus. These first and second die units 4, 5 may be positioned, arranged or oriented together relative to each other to form a complete die for the cutting tool 20. The mould units 4, 5 can also be considered as partial moulds.

Thus, the die unit is preferably considered to be one of two or more elements constituting a part of a die of the cutting tool to be manufactured. Such a mould unit may be provided in one piece as the first mould unit 4, or may be formed from a plurality of pieces, for example the mould unit 5. In the shown embodiment each mould unit comprises pipes end to end, so that each mould unit has at least two openings. The opening of the first mould unit is preferably configured to be connected with the opening of the second mould unit, thereby forming a continuous mould 14, 15. Preferably, one or both of the two other openings are preferably used for inserting a pressurized punch and/or more generally for applying pressure to the powder provided in the continuous die.

In other embodiments, not shown in the figures, the invention comprises the use of three or more part moulds 4, 5 or part mould units connected to form the entire mould of the cutting tool. For example, the invention comprises three, four, five or more mould parts which can be connected to form a continuous mould for a cutting tool manufactured by pressing.

Note that preferably at least one of the two mould units 4, 5 is displaceably arranged relative to the other of the two mould units, so that the two mould units 4, 5 can be connected to form a mould and/or can be separated from each other, thereby allowing removal of the cutting tool 20 manufactured in the mould.

The openings 8, 9 provided in the die units are preferably such as to allow the pressurized punches 12, 13 to enter the holes and/or channels 24, 25 provided in the first and second die units. The holes and/or passages 24, 25, 28 preferably allow the pressurized punches 12, 13 to enter the respective holes and/or passages 24, 25, 28 in order to apply pressure to the powder 30 contained therein, as will be described in more detail elsewhere.

In fig. 2A, a first press punch 12 and a second press punch 13 are also shown. First press punch 12 comprises a preferably cylindrical punch rod 31, an optional collar 33 and a shank 32. Shank 32 and collar 33 are designed for connecting press punch 12 to a press adapted to produce a linear pressing motion along an axis, preferably a vertical axis, for pressing a cutting tool as described elsewhere in this specification. For example, an electric press may be used to apply the pressure. As shown in fig. 1, collar 33 is located on and abuts a first punch support 81 to which shank 32 is releasably secured as in a bore.

Second press punch 13 further includes a shank 37 and an optional collar 38 to facilitate releasable but rigid securement to second punch support 82 (fig. 1). The punch stem 39 of the second press punch 13 is different from the punch stem in the first press punch 12 due to the action of the second press punch 13 with respect to the second die unit 5 including the ridge 3. Punch stem 39 includes a thinned region or stem 41, the diameter of which region or stem 41 is smaller than the diameter of punch stem 31 or the upper portion of punch stem 39. The rod 41 connects the head 22 of the second press punch with the larger area of the longitudinal rod 39. The purpose of the thin stem 41 of the stem 39 is to allow the head 22 to penetrate into the die area 15 when pressing and/or ejecting a pressed cutting tool, as described elsewhere in this specification. The head 22, stem 41, longitudinal rod 39 and handle 37 of the ejector rod 21 are preferably coaxial.

The head 22 of the second press punch preferably comprises a cut-out or a straight external thread to allow it to move through the helical ridge 3 in the second die unit 5 by a linear rotational movement. Thus, at least the head 22 or, as in the illustrated embodiment, the entire press punch 13 is preferably configured to be able to rotate when moving along its axis.

The dimensions of the rod 31, 39, the rod 41 and the cut-outs in the head 22 are such that the punch can enter the respective die unit 4, 5 and/or the piece 43 in a matching, suitable manner. The holes and channels 14, 24, 25, 15 are preferably just large enough to allow the rod to enter without causing any undue friction and wear, but without leaving too much space to occupy the respective holes and channels in a maximized, optimal manner.

It should also be noted that the collars 33, 38 provided on the press punches are optional and are preferably provided to facilitate accurate positioning of the press punches 12, 13 in their respective punch holders 81, 82.

Fig. 3A and 3B show a powder filling receptacle or funnel 40, which is preferably displaceably arranged with respect to the inventive device 100. In fig. 3A, the funnel 30 is empty, but is placed in a guide structure or housing 42. The hopper containing the powder 30 is shown in fig. 3B. The hopper 40 may be filled with powder at a particular location on the apparatus and, after filling, may be displaced to release the powder at a desired location for filling the mold. The displacement of the hopper 40 and other movable parts of the apparatus, such as the moulds 4, 5, is preferably actively driven, for example by a motor or a pneumatic or hydraulic actuator, and guided by a guide structure 93 (fig. 1).

In one embodiment, the method of the present invention comprises the step of forming a mould by connecting and/or releasably connecting two separate mould units 4, 5 or part mould parts 14, 15.

In one embodiment, the method of the present invention comprises the steps of: the moulds 14, 15 are composed of the first mould unit 4 and the second mould unit 5 by bringing the first opening 6 of the first mould unit 4 into contact with the first opening 7 of the second mould unit 5.

Fig. 4A and 4B show a configuration in which the first mold unit 4 is brought into contact with and aligned with the second mold unit 5. In particular, the first opening 6 of the first mould unit 4 is in contact with the first opening 7 of the second mould unit 5. In the embodiment shown, the first opening 7 of the second mould unit 5 is a free opening of the insert 50. In this configuration, the conduits 24, 25 and 28 in the first and second die units are aligned to form one single straight conduit having a single axis 27.

In one embodiment, the first and second mould units are connected by moving at least one mould unit into contact with the respective other mould unit. For example, the moving mold unit moves along a common axis, for example, along a vertical axis. For example, the configuration shown in fig. 4A and 4B may be achieved by holding the second mold 5 in a fixed position and moving the first mold unit 4 upwardly (along axis 27) in a linear motion until it is connected to the second mold unit 5.

The complementary tubular form of the respective tubular end regions 34 and 35 at the respective first openings 6, 7 of the first mould unit 4 and the second mould unit 5 facilitates accurate alignment of the opening 7 provided at the bottom of the second mould unit 5 with the opening 6 of the first mould unit 4. In the embodiment shown, the tubular collar 34 of the first mould unit 4 fits into the tubular collar 35 provided by the second mould unit 5 at the opening 7. In the embodiment shown, the collar 35 at the second mould unit 5 is provided by a mould holder 43, in particular by an opening of the cavity 26 in which the insert 50 is provided (fig. 2A). Of course, the present invention includes the reverse arrangement in which the collar 35 provided at the second mold unit 5 is fitted into the collar provided at the first mold unit 4. Furthermore, the present invention may provide other and/or additional means for stabilizing or guiding the alignment of the mould units on the axis and/or for connecting the mould units in a reversible, releasable manner.

In one embodiment, the ends of the first 4 and second 5 mould dies have geometrically complementary mating forms at their openings 6 and 7, allowing a stable connection of the two moulds 4, 5 on a common axis. In other words, the mating form prevents one of the molds from being displaced relative to the other mold along an axis perpendicular to the common axis 27.

In one embodiment, the first die unit 4 is in communication with a punch entry port 8, the method comprising the steps of: the punch inlet opening 8 is closed by positioning a pressurized punch 12 at or in the punch inlet opening 8 before the first and second die units 4, 5 are filled with powder. In the illustrated embodiment, the punch inlet opening 8 corresponds to a second or bottom opening of the die unit 4, which is provided by a conduit 24 in the die unit 4.

It should also be noted that in fig. 4A and 4B, first punch 12 is also aligned on common axis 27, so that conduits 24 and 25 of first and second die units 4, 5 and punch stem 31 of first punch 12 are coaxial. Note that the free end of the punch rod 31 is in contact with the second opening 8 of the first die unit 4. In particular, the punch rod 31 slightly passes through the opening 8 into the duct 24. In this configuration, first opening 8 is closed or covered by punch 12. The invention consists in that the first stamping bar 31 can be advanced further into the duct 24 of the first die unit 4 than shown in the figures, thereby substantially closing the second opening 8. It should also be noted that said closing of the opening 8 by the punch 12 does not necessarily have to be airtight, but has the purpose of preventing the powder 30 from leaking when filling the die. The allowed play between the rod 31 and the opening 8 and the duct 24 depends to some extent on the particle size of the powder of the tool 20 used for pressing.

It can be seen that by coaxially aligning the first and second mould units 4, 5 as described, the first mould region 14 of the first mould 4 and the second mould region 15 provided by the second mould 5 can be formed into a continuous, complete and/or "unitary" mould 14, 15. If an insert 50 is used as in the illustrated embodiment, the conduit 28 in the insert (or a portion thereof) preferably provides the second mold region 15. In this case, the conduits 28 of the insert are preferably also aligned and/or coaxial with the conduits 24 and 25.

As can be understood from fig. 4A and 4B, when the two dies 4, 5 are in contact at their respective first openings 6, 7, and when the second (or bottom) opening 8 is covered, the ducts 24, 25 form a cavity comprising a single opening, in particular the top opening 9, which in the illustrated embodiment is the second and/or punch entry opening of the second die 5.

In one embodiment, the method of the present invention comprises the step of filling the first mould 4 and the second mould unit 5 with powder 30. In particular, the mould may be filled with powder through the opening 9.

The powder 30 may be a commercially available powder, which is typically used for manufacturing cutting tools by pressing, for example. In one embodiment, the powder is selected from powders comprising carbide, ceramic, metal, nitride or cermet powders, or powders comprising a mixture of one, two or more of the foregoing powders. Examples of nitride powders are, for example, boron nitride, titanium nitride, silicon nitride and chromium nitride powders. Preferably, a carbide powder, most preferably a tungsten carbide powder, is used or included in the powder 30.

Preferably, the powder is a powdered composition comprising a carbide and one or more metals, such as a cermet powder and/or a cemented carbide powder.

In a preferred embodiment, the powder 30 is a powdered composition further comprising one or more organic components. Preferably, the one or more organic components constitute from 0.5 to 10 wt.% of the powdered composition, preferably from 1 to 5 wt.% of the powdered composition.

In a preferred embodiment, the one or more organic components comprise 1.4 to 3 wt%, preferably 1.5 to 2.5 wt% of the powdered composition.

The organic component preferably has binding properties allowing the inorganic powder components to adhere together after pressurization. Such organic components are therefore often referred to as binders. The binder maintains the pressed tool including the pressurized inorganic powder in a pressurized shape and prevents the tool from breaking when removed from the mold.

In a preferred embodiment, the powder is a powdered composition comprising the inorganic component (carbide, metal, cermet, etc., as mentioned elsewhere) and one or more organic binders.

The organic component, in particular the binder, may for example be selected from waxes and PEG (polyethylene glycol). Typically, the powder (or powdered composition) to be pressurized comprises one of a wax and PEG. Possibly, other organic polymers may be used as binders. Preferably, the organic component consists essentially of the binder.

In a preferred embodiment, the above percentages of organic components are applied to one or more selected from the group consisting of waxes, PEG and other organic polymers. The other organic polymer may be selected from cellulose and its derivatives, such as alkyl cellulose and nitrocellulose. For the purposes of this specification, ethanol and/or ammonium stearate are not considered binders, and the powder is preferably free of ethanol and/or ammonium stearate.

In a preferred embodiment, the one or more organic components comprise and/or consist essentially of one of a wax and PEG. Preferably, the powder is a powdered composition comprising at least 30 wt% wax and/or PEG, preferably at least 50 wt%, more preferably at least 75 wt%, most preferably at least 90 wt% wax and/or PEG.

Interestingly, powders comprising relatively small amounts of organic components can be used according to the present invention. Typically, to produce a stick by extrusion as described above, the powder contains about 15 wt.% wax. In this case, a separate dewaxing step is required prior to sintering due to the large amount of wax. Typically, dewaxing is carried out in a special furnace (dewaxing or H2 furnace). Dewaxing in such furnaces is typically carried out at temperatures below 500 c, for example at 200 c. Sintering is typically carried out at temperatures above 1000 c, for example at about 1400 c.

In the case of the present invention, a small amount of organic binder is included in the powder. This has the advantage that a separate dewaxing step can be omitted. The pressed or precursor tool can be sintered directly, thus eliminating the need for separate dewaxing.

In one embodiment, the method of the present invention includes sintering the pressed cutting tool, green tool, and/or precursor cutting tool prior to sintering without a separate dewaxing step.

Fig. 4B shows a funnel 40 which is filled with powder 30 and has been displaced to be positioned directly above the opening 9 of the second mould unit 5.

As described above with respect to fig. 1, the hopper 40 may be guided on the horizontal rails 93, for example, from a horizontal filling station to the powder releasing position shown in fig. 4B. In a preferred embodiment, the mould formed by the moulds 4, 5 is filled by gravity, which is the force used to fill the successive moulds comprising the mould units 4 and 5.

Fig. 5 shows the mould units 4 and 5 filled with powder 30, the powder 30 having been released from the movable container 40, preferably by gravity. In fig. 5, the receptacle 40 has been removed, for example by moving back to the filling station, before the subsequent method step, in order to access the punch entry opening 9 of the second die unit 5.

Although not shown, the apparatus of the present invention preferably comprises a sound generator, preferably an ultrasonic generator, or another powder compacting entity, such as a vibrating entity. In one embodiment, the method of the present invention comprises the steps of: exposing the powder to sound waves, preferably to ultrasound, during filling of the powder and/or while applying the pressure to the powder. Thus, the powder 30 is preferably already exposed to (ultra) sound waves in the step of filling the mould 4, 5 between fig. 4B and fig. 5. In one embodiment, the ultrasonic generator is preferably in physical contact with the die unit 4, 5, such that the sound waves penetrate the die unit 4, 5 and reach the powder 30 during filling. A sound or ultrasonic generator is preferably arranged to efficiently transmit suitable sound waves to the powder in the interior of the mould unit 4, 5. For example, a sound or ultrasonic generator (or other compact) is in direct contact with the mold or mold element.

Without wishing to be bound by theory, acoustic waves, in particular ultrasound, are believed to facilitate compaction of the powder in the die 4, 5, 50.

During filling of the die units 4, 5 with powder 30, the first press punch 12 preferably remains substantially stationary and/or does not move far away from the mouth 8, so that the free end of the stem 31 of the press punch remains closed off the second opening 8 of the first die unit 4.

In one embodiment, the method of the present invention comprises the steps of: pressure is applied to the powder 30 to obtain a pressed cutting tool, a blank tool and/or a precursor cutting tool 20. Preferably, said pressure is exerted by one or both of said first and second presser punches 12, 13.

Fig. 6A, 6B and 6C but in particular the transition between fig. 6B and 6C illustrates the pressing process of the cutting tool 20, wherein one or both of the pressing punches 12, 13 are moved along the common axis 27, causing the punches to approach each other and the powder in the die to be pressed.

In fig. 6A, second press punch 13 has been aligned with first punch 12 so as to be coaxial with first punch 12 and also with conduits 24 and 25 of die units 4, 5. In fig. 6B, the second pressurized punch has been inserted into the tube 25, just down to the level of filling of the powder in the tubes 24, 25. In fig. 6B, the movement of the second punch 13 is stopped at a position just where the head 22 of the punch comes into contact with the powder. The first punch 12 has not moved yet and therefore still functions to close the lower opening (or the second opening 8) of the first die unit 4. During the movement of the second punch 13, and generally in the position shown in fig. 6B, the powder 30 has not yet been subjected to pressure.

In one embodiment, during said step of applying pressure to said powder, a pressing punch is moved, preferably in a punch entry port of the respective die unit.

In one embodiment, said first die unit 4 comprises a punch inlet port 8, and wherein during said step of applying pressure to said powder, a pressurized punch 12 is moved in said punch inlet port 8 of said first die unit 4. As can be seen in fig. 6B, the first punch 12 preferably moves in the duct 24 of the first die 4.

In an embodiment, said second die unit 5 comprises a punch inlet port 9, and wherein during said step of applying pressure to said powder, a pressurized punch 13 is moved in said punch inlet port 9 of said second die unit 5. As can be seen in fig. 6B, the second punch 13 preferably moves in the duct 25 and/or 28 of the second die 5.

In one embodiment, during said step of applying pressure to the powder 30, the first and/or second pressing punches 12, 13 are moved along a common, preferably vertical, axis 27.

In one embodiment, the method of the present invention comprises the steps of: providing a first press punch 12 and/or a second press punch 13; providing a first punch inlet port 8 in communication with the first die unit 4 and/or a second punch inlet port 9 in communication with the second die unit 5, wherein during said step of applying pressure to the powder, the first pressurized punch 12 is moved through the first punch inlet port 7 to apply pressure to the powder and/or a second pressurized punch 13 is moved through the second punch inlet port 9 to apply pressure to the powder.

In one embodiment, during said step of applying pressure to said powder 30, said first and second pressing punches 12, 13 are coaxially arranged on a common axis 27 and said first or second pressing punch 12, 13 or both are moved along said common axis 23, 27 in a converging direction, thereby applying pressure to said powder.

According to the embodiment shown in the figures, the first pressing punch 12 is a lower or bottom-up pressing punch 12, said pressing punch 12 moving in an upward direction during said step of applying pressure to the powder 30, and/or wherein the second pressing punch 13 is an upper or top-down pressing punch 13, said pressing punch 13 moving in a downward direction during said step of applying pressure to the powder 30.

Starting from the position shown in fig. 6B, one or both of the first and second punches 12, 13 can now be moved along the axis 27 to penetrate further into the ducts 24 and 25 of the dies 4 and 5 to exert pressure on the powder in the successive dies 14, 15. Preferably, in the method of the invention, one or both of first punch 12 and second punch 13 are translated along their common axis 27 so as to approach each other and pressurize powder 30. Note that the outside dimensions of the punch rods 31, 39 are such that they fit the dimensions of the conduits 24, 25. Thus, the first punching rod 31 passes (further) through the second opening 8 of the first die unit 4 and/or the second punching rod 39 passes (further) through the second opening 9 of the second die unit 5. Preferably, first punch 12 and/or second punch 13 move along a common axis with a linear translational movement. The first punch 12 preferably performs a non-rotational motion while applying pressure to the powder 30. In the illustrated embodiment, first pressing punch 12 moves in a bottom-up direction.

It is evident that when only one punch is moved to compress the powder, the respective other punch is preferably fixed in a specific position, preferably in a vertical position, so as to support the counter-pressure transmitted by the force exerted on the powder from the moving punch.

Fig. 6C illustrates a stage where both punches 12 and 13 have approached the powder 30 and applied pressure to the powder 30. Thus, the first pressurized punch has been raised along the axis 27 and the second pressurized punch has been lowered along the axis to compact the powder 30.

In one embodiment of the method of the invention, the first and second pressing punches 12, 13 apply pressure to the powder by means of successive advancing movements of the punches with respect to the die units 4, 5. Thus, one of the two punches is moved first, and then the other punch is moved to further compress the powder. The first and second punches may have only two successive alternating movements, or a series of successive alternating movements.

In one embodiment, the first punch at the bottom starts to press the powder by moving upwards. Preferably, the pressurized punch 12 is preferably moved until a predetermined counter pressure or force is reached. After the first punch has completed its stroke, the second punch 13 applies pressure by moving downwards along the common axis 27.

In one embodiment, the method comprises the steps of: providing a press punch 13, said press punch 13 comprising a head 22, said head 22 comprising a complementary shape such as a cut-out or an external thread, e.g. to allow said press punch to move through said die part 15 comprising a helical ridge 3 by a linear rotational movement. The form of the head 22 is therefore preferably complementary to the formation 3 (fig. 2A) of the inner surface on the mould part 15, the formation 3 of the inner surface on the mould part 15 defining the recess 10 of the tool 20 to be manufactured.

In one embodiment, the method of the present invention comprises the steps of: the pressing punch 13 is rotated while applying pressure to the powder, and preferably the pressing punch 13 is rotated and linearly moved while applying the pressure.

In one embodiment, in the step of applying pressure to the powder 30, the head 22 of the press punch 13 is advanced into the second die part 15 comprising the ridges 3, wherein the head 22 and/or the press punch 13 rotate about the axes 23, 27 as it is advanced into the second die part 15.

During the step of applying pressure, the second punch 13 (or only the head 22 thereof) is preferably rotated. In this way, the second punch, in particular the head 22 of the second punch, moves along the portion 15 comprising the ridge 3 of the die unit. This is possible because the design of the head 22 preferably comprises a shape, e.g. cut-out, matching the helical ridge 3, allowing the head to rotate while moving in the duct 28, while being close to the inner wall of the duct 28, in order to effectively apply pressure to the powder.

To allow punch 13 to advance through section 15, only head 22 needs to rotate. In principle, the lever 39 and/or the lever 41 may not rotate during said step. This may be achieved, for example, by rotatably connecting the head 22 to the second punch 13. For example, head 22 may be rotatably connected to either rod 39 or rod 41. Alternatively, the entire punch 13 may be caused or allowed to rotate.

It is also worth noting in this context that the rotational movement of the second punch 13 (or its head 22) may be an active or passive rotational movement. For example, the punch 13 or only the head 22 may be caused to rotate, preferably in a determined manner, by a motor or other suitable propulsion means. Alternatively, the punch or head 22 may be configured to be passively rotatable, e.g. housed in a bearing or ball bearing, which allows the punch 13 and/or head 22 to be passively rotated as it advances in the section 15 comprising the helical ridge 3. The force exerted by the helical ridge will then cause the head 22 to rotate as it advances in the conduit 28.

Second punch 13 is preferably moved along axis 27 until a predetermined counter pressure or force is reached.

The apparatus of the present invention preferably comprises one or more force sensors adapted to determine the force exerted by one or both of the pressurized punches at a particular time.

Preferably, the data processing entity is configured to apply the pressure until a pressure or force threshold is reached.

In another embodiment, the data processing entity is configured to perform a movement of a predetermined distance and/or a predetermined speed during the step of applying pressure.

In another embodiment, the data processing entity is configured to perform a movement with a predetermined maximum speed and up to a certain force during the step of applying pressure.

In one embodiment, the data processing entity is configured to apply an algorithm when moving the pressing punch during the step of applying pressure, wherein the algorithm may use one or more or all of the parameters selected from the group consisting of: (1) the force determined by the data processing entity and/or by the force sensor, (2) the speed of movement of the ram, and (3) the distance the ram has traveled.

Preferably, the apparatus and/or data processing entity of the present invention is readily configurable by an operator or technician and allows the operator or technician to input one or more of a predetermined force, speed and/or distance to be applied from the pressurized punch during the step of applying pressure.

In some embodiments, the top-down punches move first, while the bottom-up punches move upward in a subsequent step of applying pressure. Alternatively, the punch from bottom to top is moved first, and then the punch from top to bottom is moved. In other embodiments, the first and second punches move and apply pressure simultaneously.

In a preferred embodiment, the non-rotating press punch, here the first punch 12, performs a first pressing movement followed by a pressing movement of the rotating punch 13.

In other embodiments of the sequential steps of applying pressure, the rotating punch moves first and then the non-rotating punch applies pressure.

In one embodiment, the rotary punch 13 rotates only during a portion of the step of applying pressure. As can be seen in fig. 5 and 6A, the top filling level of the powder 30 coincides with the top end 16 of the section 28 of the mould unit 4, said mould unit 4 comprising a spiral ridge. Thus, the second punch must be rotated to be able to apply pressure and compact the powder 30 while entering the section 28. The present invention also contemplates filling the tubes 24, 25 to a level above the top end 16 of the tube 28/insert 50. The punch 13 may or may not rotate when pressure is applied without entering the conduit 28.

In other embodiments, none of the pressurized punches are rotating. In another embodiment (fig. 10A and 10B), the two pressing punches may have straight cylindrical punching rods 31.

In another embodiment, one of the two punches, for example the lower punch 12 or the upper punch 13, does not in fact actively exert pressure while moving, but stays in a fixed position and works as a support, supporting and bearing the pressure exerted by the other of the two punches on the powder 30 while compacting it. In this case, the non-moving punch may actually be a simple locking structure, and not necessarily a movable pressing punch.

During the step of applying pressure to the powder 30, a compaction unit, such as an ultrasonic generator, is preferably activated so as to continue to act on the powder while it is subjected to pressure from one or both of the pressurizing punches. In the case of a successive movement of two separate pressing punches, the compacting unit is preferably actuated during two movements of the pressing punches. In another embodiment, during the step of applying pressure to the powder, the compaction unit is only actuated during one or some but not all movements of the pressing punch. Preferably, the compacting unit is activated during at least part of the step of applying pressure to the powder.

After the step of applying pressure to the powder is completed, the pressed cutting tool will be accommodated in the die unit 4, 5 (fig. 6C). The method of the present invention preferably includes the step of removing the pressed cutting tool from one or both of the die units.

Preferably, care is taken not to break or otherwise damage when removing the pressed cutting tool 20 from the mold.

In one embodiment, the removal of the tool 20 from the mold is accomplished in two or more separate processing steps.

In a first step, pressure from first or bottom punch 12 is first released. Preferably, the punch 12 is held in contact with the lower end of the pressed tool 20, as shown in fig. 6C.

In one embodiment, the first or bottom mold 4 is removed first. In one embodiment, the method comprises the steps of: the first die unit 4 is moved linearly away from the pressed tool 20 along the axis 23, 27 for relative movement with respect to the pressed tool 20 and/or the press punch 12. The method steps are best illustrated by the transition from fig. 6C to fig. 7. The mould unit 4 has moved downwards and is no longer visible in figure 7. It is noted at this point that the length of the punch rod 31 is preferably longer than it is shown in the figures, so that the entire die unit 4 can be moved preferably along the axis 27 until the shank 1 (fig. 2B) of the tool 20 is completely ejected from the die 4. As shown in fig. 7, the first punch 12 preferably remains in contact with the bottom end of the shank during the linear movement of the removal die 4.

Preferably, the die component 4 defining the shank of the cutting tool is first removed. In the embodiment shown, this is the first or bottom mold 4. The first removed mould unit may also be the top mould unit 4 or a laterally positioned mould unit, as the invention is not limited to a specific orientation of the mould in the method of the invention.

In one embodiment, the method of the present invention comprises the steps of: the first press punch 12 is removed from the pressed tool 20, preferably after the first die unit 4 is removed from the tool 20. As shown in fig. 7, after removal of first die 4, first pressing punch 12 is preferably removed by a translational movement along axis 27 in a direction opposite to the direction in which the pressing force is applied. Preferably, the first or bottom punch 12 is lowered.

The process of completely removing the pressed tool 20 from the second mould 5 is illustrated in fig. 8 and 9. In one embodiment, the method of the present invention comprises the steps of: the press tool 20 is preferably removed from the second die unit 5 by linearly moving the press punch 13 through the second die unit 5, preferably simultaneously with the linear and rotational movement of the press punch 13 (possibly only the head 22 is rotated). In other words, the data processing entity advances the punch 13 further into the tube 28 of the die unit 5 comprising the helical ridge. As mentioned above, the punch 13, or at least the head 22, must be rotated in order to be able to advance in the pipe 28, since the pipe 28 does not have a constant cylindrical cross section but contains a structure defining a helical groove of the tool 20. The second punch 13 preferably passes through the entire conduit 28 until it reaches the first opening 7 of the second die unit 5, as shown in fig. 9. In this position, the cutting tool 20 has been fully ejected from the second mold portion and will fall out. The collection can be performed manually or by means of a suitable collection device.

Fig. 10A and 10B illustrate another embodiment of the method and apparatus of the present invention. According to this embodiment, the second press punch 13' differs from the second press punch 13 in the preceding figures in that it is not adapted to enter the duct 28 of the second die unit 5 in which the second die zone 15 is provided. The second press punch 13' preferably lacks a head 22, said head 22 comprising a cut or similar shape complementary to the second die area 15. The second punch 13' also preferably lacks a stem 39, said stem 39 having a thinner cross-section, as shown for the punch 13 in the previous figures. Therefore, the second press punch 13' of the present embodiment may not be configured to rotate, or may not rotate in the step of applying pressure. For example, the second press punch may be configured to apply pressure to the powder 30 in a similar manner to the first press punch, and may have the same overall configuration.

The cutting tool 20 may be prepared entirely as described above, except that the second press punch 13' is not advanced into the conduit 28 of the second die unit. The punch 13' preferably stops linear movement at the opening 16 of the insert 50 or before reaching the opening 16.

In order to eject the pressed tool 20 obtained according to the second embodiment, it is necessary to extract the second press punch 13' from the second die unit 5 and use the ejection punch 13 as shown in the previous figures. Accordingly, according to the alternative embodiment shown in fig. 10A and 10B, the punch 13 shown in these figures is preferably still used for ejecting the pressed tool 20, but preferably, said punch 13 is not used for applying pressure.

Another difference of this second embodiment can be seen when comparing fig. 5 and 6A on the one hand with fig. 10A on the other hand. In fig. 10A, the powder is filled above the level 16 of the duct 28, which characterizes the presence of the second die area 15 for this duct. In fig. 5 and 5A, the powder 30 is preferably filled substantially no higher than the opening 16. Thus, in the first embodiment, pressure may be applied from near or below (or from above) the opening 16, while in the second embodiment, pressure has been applied from above the opening 16.

Once the tool 20 is ejected, a cutting tool, a blank tool and/or a precursor cutting tool is preferably obtained. The tool may be commercialized as such, or may be subjected to further steps for further processing and/or refinement. In one embodiment, the method of the invention comprises one or more of the following further steps: (1) hydrogen dewaxing, (2) sintering, (3) cutting, (4) centerless grinding, (5) groove grinding, (6) honing, (7) coating, and/or (8) cleaning. Of course, the present invention does not exclude other or further steps of completing the cutting tool ready for use.

From the present description, it is clear that the term "pressing" is used in the context of preferably pressing the material 30 provided in the mould or mould units. The term "pressing" is therefore not intended to mean the production of a billet by extrusion, for example through a nozzle. "pressing" may be referred to in accordance with the present invention as coining or mold-based pressing.

Examples of applying pressure by means of one or two coaxial pressurizing rods have been discussed in detail with reference to the figures. The invention also includes the possibility of applying pressure to the powder in the mould from the side and/or in a non-axial manner. For example, in one embodiment, the die body may comprise a lateral opening therein provided at the pressing structure, such that the powder may be pressed from the pressing structure pressing the powder in a non-axial direction. Such non-axial or transverse compressive forces may be used, for example, to form openings or flat sides or concavities in cutting tools. Such openings, flat surfaces or cavities may thus be disposed transversely with respect to the axis of the cutting tool, and may result in a reduced number of axes of symmetry of the tool, and/or may result in the cutting tool not being axially symmetric. The present invention also contemplates the use of interlaced or nested mold parts that can be displaced to pressurize the powder contained in the internal cavity formed by the interlaced, intersecting and/or nested mold parts.

Furthermore, the figures show the invention comprising two mould units connected to form a continuous mould. In another embodiment, a single mold unit comprising a mold is included. In other words, the mold of the tool may be contained entirely in a single piece, or in a plurality of rigidly connected pieces. Preferably, such a mold further comprises at least two openings to allow one or two coaxial pressing bars to enter the mold and to allow ejection of the cutting tool after pressing. In the case of a single mould unit, the mould unit may or may not comprise a first mould region defining at least part of the shank, and a second mould region comprising ridges designed to define the grooves of the tool to be manufactured. The single die unit may define only helical ridges or may define only rods that do not have helical grooves, e.g., substantially cylindrical rods. When a single mould unit is used, the method may generally be carried out according to the steps described in this specification, except for the step of displacing one or both of the two part mould units relative to the other.

According to the above embodiments, the present invention also provides an apparatus comprising only one mold assembly, such as a single mold assembly or a single mold unit.

In the foregoing specification, reference has been made to certain publications and patent documents in order to more fully describe the state of the art to which this invention pertains. The disclosure of each of these references is incorporated herein by reference.

While certain preferred embodiments of the present invention have been described and specifically exemplified above, it is not intended that the present invention be limited to these embodiments. Various modifications may be made thereto without departing from the scope and spirit of the invention as set forth in the appended claims.

Claims (27)

1. A method of making a cutting tool, a blank tool and/or a precursor cutting tool (20), the method comprising the steps of:

-providing a first mould unit (4) and a second mould unit (5),

wherein the first mould unit (4) comprises a first mould part or region (14), the first mould part or region (14) defining at least a part of a shank (2) of the tool (20) to be manufactured,

wherein the second mould unit (5) comprises a second mould part or region (15), the second mould part or region (15) comprising a ridge (3), the ridge (3) being designed to define a groove (10) of the tool (20) to be manufactured,

wherein the first and second mould units (4, 5) comprise a first opening (6, 7), respectively;

-composing a mould (14, 15) from the first and second mould units (4, 5) by bringing a first opening (6) of the first mould unit (4) into contact with a first opening (7) of the second mould unit (5);

-filling a powder (30) comprising a carbide, ceramic, metal, nitride or cermet powder or a powder comprising a mixture of one, two or more of the above into the first and second mould units (4, 5);

-applying pressure to the powder (30) thereby obtaining a pressed cutting tool, a blank tool and/or a precursor cutting tool (20).

2. A method according to claim 1, wherein the first mould unit (4) comprises a second opening (8), the method comprising the steps of:

-closing the second opening (8) by positioning a pressing punch (12) at or in the second opening (8) before filling the powder into the first and second die units (4, 5).

3. The method according to claim 1 or 2, wherein the first die unit (4) comprises a second opening (8) and during the step of applying pressure to the powder a pressurized punch (12) is moved within the second opening (8) of the first die unit (4).

4. Method according to any of the preceding claims, wherein the second die unit (5) comprises a second opening (9), and wherein during the step of applying pressure to the powder a pressing punch (13) is moved through the second opening (9) of the second die unit (4).

5. The method according to any of the preceding claims, comprising the steps of:

-providing a first pressing punch (12) and a second pressing punch (13);

-providing a first punch inlet opening (8) communicating with the first die unit (4) and a second punch inlet opening (9) communicating with the second die unit (5);

wherein in the step of applying pressure to the powder, the first pressure punch (12) is moved through the first punch inlet port (8) to apply pressure to the powder and/or the second pressure punch (13) is moved through the second punch inlet port (9) to apply pressure to the powder.

6. A method according to claims 3-5, wherein the first and second pressing punches (12, 13) apply pressure to the powder by means of a continuous advancing movement of the punches with respect to the die units (4, 5).

7. The method according to any of the preceding claims, comprising the steps of: during filling of the powder, the powder is exposed to ultrasound.

8. The method according to any of the preceding claims, comprising the steps of: exposing the powder to ultrasound while applying the pressure to the powder.

9. The method according to any one of the preceding claims, wherein the powder is a powdered composition further comprising one or more organic components, in particular organic binders, wherein the one or more organic components comprise 0.5-10 wt%, preferably 1 wt% to 5 wt% of the powdered composition.

10. The method of claim 9, wherein the one or more organic components comprise from 1.25 wt% to 3 wt%, preferably from 1.5 wt% to 2 wt% of the powdered composition.

11. The method of claim 9 or 10, wherein the one or more organic components comprise and/or consist essentially of one of a wax and/or PEG.

12. The method according to any of the preceding claims, comprising the steps of:

-providing a press punch (13) comprising a head (22), said head (22) comprising a complementary shape such as a cut or an external thread, allowing the press punch to move through the second die part (15) comprising ridges (3) by a linear rotational movement.

13. The method according to any of the preceding claims, comprising the steps of:

-rotating a pressing punch (13) while applying pressure to the powder, preferably rotating and linearly moving the pressing punch (13) while applying the pressure.

14. Method according to any one of the preceding claims, wherein, during the step of applying pressure to the powder (30), the first and second pressing punches (12, 13) are coaxially arranged on a common axis (23) and the first or second punches (12, 13) or both are moved along the common axis (23, 27) in a converging direction, thereby applying pressure to the powder.

15. The method according to any of the preceding claims, comprising the steps of: removing the first mould unit (4) from the pressed tool (20) by linearly moving the first mould unit (4) along an axis (23, 27) of the tool (20) and/or the first mould unit (4).

16. The method of claim 15, comprising the steps of: -linearly moving the first die unit (4) along the axis (23, 27) away from the pressed tool (20) for relative movement with respect to the pressed tool (20) and/or the press punch (12).

17. The method according to any of the preceding claims, comprising the steps of: -removing a first press punch (12) from the pressed tool (20), preferably after removing the first die unit (4) from the tool (20).

18. The method according to any of the preceding claims, comprising the steps of: -removing the pressed tool (20) from the second die unit (5) by linearly moving a pressing punch (13) through the second die unit (5) while the pressing punch (13) performs a linear and a rotational movement, or at least a head (22) of the punch (13) performs the rotational movement.

19. Method according to any one of the preceding claims, wherein a first pressing punch (12) is a lower or bottom-up pressing punch (12) which moves in an upward direction during the step of applying pressure to the powder (30), and/or wherein a second pressing punch (13) is an upper or top-down pressing punch (13), the pressing punch (13) moving in a downward direction during the step of applying pressure to the powder (30).

20. Method according to any one of the preceding claims, wherein during the step of applying pressure to the powder (30), the first (12) and second (13) pressing punches are moved along a common, preferably vertical, axis (27).

21. A method according to any of the preceding claims, wherein the second mould unit (5) comprises a removable insert (50), the insert (50) comprising the second mould part or region (15).

22. The method according to any one of the preceding claims, wherein the cutting tool, blank tool and/or precursor cutting tool (20) is a solid radius tool, a blank solid radius tool and/or a precursor solid radius tool, preferably an end mill, a blank end mill or a precursor end mill, more preferably a solid end mill, a solid blank end mill or a solid precursor end mill.

23. Apparatus for manufacturing a cutting tool, a blank tool and/or a precursor cutting tool (20), preferably according to the method of claims 1-18, the apparatus comprising:

-a first mould unit (4) comprising a section with a first mould portion (14), the first mould portion (14) defining at least a part of a shank (2) of the tool (20) to be manufactured;

-a second mould unit (5) comprising a second mould part (15), the second mould part (15) comprising a ridge (3), the ridge (3) being designed to define a recess (10) of the tool (20) to be manufactured;

-at least one pressing device (12, 13) arranged to be inserted through an opening (8, 9) of the first and/or second mould unit (4, 5) and arranged to move coaxially with the axis of a mould (14, 15) formed in connection with the mould unit (4, 5) for pressing the powder (30) remaining in the mould.

24. Apparatus according to claim 23, comprising a mounting frame (60) on which said first and second mould units (4, 5) are mounted, wherein at least one of said first and second mould units (4, 5) is mounted on said mounting frame (60) so as to be movable along an axis (27) coaxial with the axis of said at least one pressing device (12, 13).

25. The apparatus of claim 23 or 24, comprising: -a mounting (60) and-a container (40) for receiving the powder (30), the container (40) being mounted on the mounting (60) so as to be movable in order to convey the powder (30) towards an opening (9) of a mould formed by the first and second mould units (4, 5), the container comprising an outlet designed to transfer the powder to the mould (4, 5).

26. Apparatus according to any one of claims 23-25, further comprising a sound generator arranged to expose the powder present in the mould (4, 5) to sound, preferably ultrasound.

27. A method of making a cutting tool, a blank tool and/or a precursor cutting tool (20), the method comprising the steps of:

-providing a mould (4, 5), wherein the mould (4, 5) comprises a first and a second opening (6, 7);

-filling a powder (30) comprising a carbide, ceramic, metal, nitride or cermet powder or a powder comprising a mixture of one, two or more of the above into the mould (4);

-applying pressure to the powder (30) thereby obtaining a pressed cutting tool, a blank tool and/or a precursor cutting tool (20).

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