Square blade for bar peeling and blade holder tool for the same

Abstract

A square bar parting blade and a blade holder designed to have recesses to hold two such square blades. Each blade has four peripheral sub-surfaces and corners. Between each pair of adjacent corners is a cutting edge comprising a straight wiping sub-edge and two at least partially curved parting sub-edges on opposite sides of the wiping sub-edge, respectively. The corners of the blade are inwardly disposed relative to an imaginary square formed by the sub-edges.

Description

Technical Field

[0001] This application relates to bar stripping blades, blade holders, and tool assemblies including the same. More specifically, the subject matter relates to square bar stripping blades and blade holders for retaining the square blades. Background Technology

[0002] Bar-peeling is a machining operation distinct from both standard turning, where the workpiece rotates, and standard milling, where the cutting tool rotates and the workpiece remains stationary. Generally, in bar-peeling, a slender bar moves axially (relatively) through the area occupied by the bar-peeling cutting tool assembly, and the peeling head rotates around the bar, thus "peeling" off the outer layer.

[0003] Such operations are characterized as very “coarse” machining operations, with large chip loads and resulting large forces on the cutting inserts and cutting components, as well as instabilities, in which a large amount of vibration is typical.

[0004] US 5,256,008 Figure 1 A schematic representation of a conventional bar stripping operation is shown, which is helpful for understanding.

[0005] The disclosure of US 5,256,008 relates to a tool assembly for a stripping operation, wherein the tool holder is provided with a roughing insert having a convexly curved cutting edge and a finishing insert having a substantially linear cutting edge. In this application, the bar stripping insert positioned to first contact the workpiece (hereinafter alternatively referred to as "bar") will be referred to as a roughing bar stripping insert (or, for simplicity, a "roughing insert"), and the bar stripping insert positioned to subsequently contact the workpiece will be referred to as a finishing bar stripping insert (or, for simplicity, a "finishing insert").

[0006] DE 35 40 665 A1 appears to illustrate a similar overall concept of a curved roughing insert (made of multiple parts) followed by a straight-edge finishing insert.

[0007] DE 2 820 810 discloses an elongated double-edged blade, wherein each edge has a peeler edge and a scraper edge, as referred to below. The peeler edge, which is inclined at an angle different from the scraper edge, is further inclined at two different angles for the stated purpose of reducing the risk of edge breakage. The reason given is that the curved shape (two different angles) is beneficial in preventing breakage but reduces surface finish. It is to be understood according to this disclosure that the use of an elongated blade also allows for deep cuts.

[0008] In publications many years after DE 2 820 810, US 7,972,092 discloses a similar blade, in which the difference appears to be that the blade not only has two different angles at the main edge, but also has multiple radii. It is noteworthy that in Figure 1 In A-1E, blade shapes described as prior art are shown. Notably, they are generally elongated, with one blade being essentially triangular in shape. Also note, in the background, that the stripping blade has a stripping edge and a scraping edge (also known as a smoothing cutting edge). It should also be explained that this smoothing cutting edge is also used in a supporting manner for the machined bar stock and is centrally guided in the stripping head.

[0009] FR 2 483 819 appears to show a convex, curved triangular blade, and an embodiment in which three such blades are used together.

[0010] Some general observations can be made regarding the cutting insert shapes of the prior art described above. Typically, prior art inserts have elongated shapes that allow for increased depth of cut and stabilization effects as described in prior art disclosures, or triangular-type shapes known in the art to be more stable given the direction of the cutting force used for bar stripping operations.

[0011] Only one prior art disclosure has been found that discloses a generally square stripping blade, namely DE 298 15761 U1. The disclosed cutting blade is similar to the slender blades of the prior art because it has a stripping sub-edge and a slender scraping (smoothing) sub-edge. Of particular concern is the lack of disclosure of a blade holder that enables the holding of the cutting blade. Related to this is the undisclosed challenge of stably mounting square blades for bar stripping operations.

[0012] US 2019 / 0054542 is the most recent disclosure found by the applicant related to bar stripping inserts, and discloses a cutting insert with even more cutting edges than DE 298 15 761 U1, namely five or six pairs of stripping and scraping edges per side (i.e., pentagonal or hexagonal cutting inserts). Given that the disclosed cutting insert can be double-sided, it can therefore have ten or twelve cutting edges (i.e., each cutting edge is a pair of stripping and scraping edges).

[0013] One object of the present invention is to provide a new and improved bar stripping blade and a blade holder therefor.

[0014] A separate objective of this invention is a novel gasket.

[0015] It will be understood that the cutting blade is not a perfect polygonal shape, and the term "square" means that a square is the closest to a regular shape (alternatively, "basically square" or "nearly square" can be used). This is similar to existing blades described as pentagonal, hexagonal, triangular, or triangular, etc. Summary of the Invention

[0016] This invention relates to providing a more versatile bar stripping blade than those known to date.

[0017] According to a first aspect of the subject matter of this application, a square bar stripping blade is provided, which includes a cutting edge; the cutting edge includes: a straight shaving edge and a first stripping edge and a second stripping edge that are at least partially curved and located on opposite sides of the shaving edge and connecting the shaving edge to adjacent corners.

[0018] Providing two opposing, at least partially curved peeler edges on one side of the bar stripping blade allows for increased versatility compared to the prior art, because the bar stripping blade thus has additional peeler edges.

[0019] Preferably, the edges of the first and second peelers are mirror-symmetrical about the center of the scraper edge.

[0020] While it may seem intuitive to provide additional cutting edges to the cutting insert, it is necessary to explain why existing bar stripping inserts do not have this construction.

[0021] The first reason is that the scraper edge is conventionally significantly elongated from the peeler edge to the end or essentially the end of the bar stripping blade. This is because bar stripping is an extremely rough machining operation, and the scraper edge provides not only a scraping function but also a stabilizing function, as mentioned above in the explanation in US 7,972,092. So-called scraper edges in other machining applications are typically much smaller (e.g., 1 mm) because their entire function is to produce a surface finish rather than stabilization, unlike bar stripping blades where the scraper edge is typically significantly longer than, or even the so-called "peeler edge."

[0022] The second reason for the squeegee's elongated edge is to allow for a greater depth of cut, as explained above with reference to DE 2 820810.

[0023] It goes without saying that by adding an additional peeler edge according to the present invention, the total length of the scraper edge is reduced from the total length that can be provided for a bar peeler blade of similar size (thereby reducing stability and cutting depth).

[0024] However, the following text combines Figure 5BIt will be understood that for this multi-purpose bar stripping blade, which is used not only for finishing purposes (and therefore has this disadvantage) but also for roughing surfaces, this disadvantage will not occur for at least one of the two proposed applications.

[0025] Furthermore, known bar stripper retainers are not designed to operate in both directions, and therefore, the end user will only need one stripper edge on one side of the cutting blade. Therefore, adding a second stripper edge offers no immediate and obvious benefit.

[0026] Therefore, the functionality of reducing the elongated swabbing edge shown in the prior art disclosure is not obvious.

[0027] Therefore, the first advantage related to the versatility of the provided blades is that the same bar stripping blade can be used in both the left and right blade holders, which is believed to outweigh the disadvantage of losing part of the scraping / stabilizing sub-edge.

[0028] In addition, unlike other machining operations, the peeler edge is relatively short compared to the scraper edge, and the scraper edge suffers less functional loss than in other applications.

[0029] However, the loss of stable length is particularly significant because the bar stripping blade here is square, rather than slender as in some existing technologies, resulting in a more significant loss of length at the scraper edge.

[0030] Therefore, to compensate for the loss of stabilizing effect, it is preferable that the bar stripping inserts are relatively large for the cutting inserts. For example, it is preferable that the inscribed circle IC of the bar stripping insert has a diameter D that satisfies the following condition: D ≥ 30 mm, more preferably D ≥ 35 mm. Nevertheless, such bar stripping inserts are generally made of relatively expensive sintered carbides, and large inserts are more difficult to press, so it is preferable that they are not made larger than necessary. Therefore, it is preferable that the insert satisfies the following condition: D ≤ 45 mm, more preferably D ≤ 40 mm.

[0031] Another significant advantage related to its versatility is that the same stripping insert can also be used as a stripping insert for roughing bar stock, utilizing the entire cutting edge along one side, and even including a second stripping edge (see...). Figure 5B ).

[0032] In other words, for at least one of the two advantages described above, providing an additional stripper edge is believed to outweigh the additional cost of increasing the cutting edge and / or the disadvantage of a shorter stripper edge, which are generally considered beneficial for bar stripping inserts.

[0033] It will be understood that this advantageous configuration can be applied to more than one side, and preferably all sides, of the bar stripping blade.

[0034] Therefore, according to a second aspect of the subject matter of this application, a square bar stripping blade is provided, comprising: a first rake face and a second surface positioned opposite thereto; a blade peripheral surface connecting the first rake face and the second surface; and a first cutting edge extending along the intersection of the blade peripheral surface and the first rake face; the blade peripheral surface includes a first peripheral sub-surface, a second peripheral sub-surface, a third peripheral sub-surface, and a fourth peripheral sub-surface, and a first corner, a second corner, a third corner, and a fourth corner connecting the first peripheral sub-surface, the second peripheral sub-surface, the third peripheral sub-surface, and the fourth peripheral sub-surface; wherein, in the first rake face... In the plan view of the blade face, between each adjacent pair of the first corner, the second corner, the third corner, and the fourth corner, the first cutting edge defines a first imaginary square and includes: a straight scraper edge; and a first peeler edge that connects the scraper edge to the first corner with at least a partial bend; and a second peeler edge that connects the scraper edge to the second corner with at least a partial bend; the first peeler edge and the second peeler edge are respectively located on opposite sides of the scraper edge; wherein, in the plan view of the first rake face: each of the first corner and the second corner is positioned inwardly spaced from the imaginary square.

[0035] It is worth noting that the preferred but optional features mentioned above (i.e., the mirror symmetry of bar stripping and the blade size) apply equally to all blade aspects.

[0036] Preferably, in the plan view of the first front blade surface: each of the first peripheral sub-surface, the second peripheral sub-surface, the third peripheral sub-surface, and the fourth peripheral sub-surface is associated with the edge of the squeegee defining the imaginary square, and each of the first corner, the second corner, the third corner, and the fourth corner is positioned inwardly spaced from the imaginary square.

[0037] As described above, inwardly spaced (or in other words, "recessed") corners are generally considered disadvantageous for cutting inserts that normally have significantly rounded or rounded corners to increase tool life. It will be understood that sharper corners are more prone to breakage. However, for a given application of bar stripping, sharp corners, or inwardly spaced corners as defined above, allow for the utilization of more cutting edges. It is important to note that, unlike other machining operations, the corners of bar stripping inserts are not intended for machining the workpiece.

[0038] It should be understood that an alternative definition of "positioned inwardly spaced from the imaginary square" for the corner can be that, in the plan view of the first rake face, the corner is a corner with a sharp edge (i.e., the opposite of a corner with a rounded edge). This also applies to the preferred embodiment having a cutting edge along the second surface.

[0039] The aspects defined above allow for square bar stripping blades to have eight bar stripping edges, which is an improvement over known triangular blades. While triangular blades offer a more straightforward and stable mounting arrangement, the stable mounting configuration of square blades will be detailed below.

[0040] While it may be noted that US 2019 / 0054542 discloses a bar stripping blade with even more edges, this invention is considered suitable at least for longer scraping (and stabilizing) sub-edges and such Figure 5B The overall machining depth length along one side of the blade, as shown in the roughing bar stripping blade, is advantageous.

[0041] According to any aspect above and below, preferably, the bar stripping insert according to the invention is reversible (i.e., a double-sided insert). In other words, opposite to the first rake face is a second rake face that forms a second cutting edge with the peripheral surface of the insert. In other words, the second surface mentioned above and in the claims may be the second rake face.

[0042] Preferably, the second rake face may be the same as the first rake face, but at least includes a cutting edge configured for bar stripping operations to be formed on a second surface positioned opposite to the rake face. In other words, the second cutting edge may include the same features as the first cutting edge.

[0043] The term "second surface" in the specification and claims refers to a second "rake" face after it indicates that this surface is a rake face (e.g., formed to have a cutting edge extending along its intersection with the peripheral surface of the insert) (even though the name "second surface" is retained for readability).

[0044] It will be understood that it is highly preferred that all cutting edges are positioned adjacent to chip forming arrangements such as grooves (of course, this is for embodiments where the cutting blade itself is a negative blade and a positive edge is required for compensation).

[0045] What will be understood is that double-sided inserts can double the number of cutting edges. This means that if there are two peeling edges along a single side of a square insert, then there can therefore be eight peeling edges on each rake face.

[0046] However, due to the roughing applications of the scraper edges (meaning they will experience more wear than scraper edges for other machining applications), it is still expected that each cutting edge along each side will only undergo a single use (until wear renders it unusable). This implies unusual designs, such as even though a bar stripper has 16 stripper edges, it is still expected to be used only as an eight-way indexable insert.

[0047] The aforementioned double-sided blade is preferably a result of the blade being a negative blade (i.e., wherein the peripheral surface of the blade extends perpendicularly to both the first rake face and the second surface), because this is the type of blade to be manufactured that is extremely efficient (even bar stripping blades may require a negative mounting position in order to provide clearance).

[0048] Nevertheless, other options besides the preferred negative arrangement are also feasible. For example, forming the blade peripheral surface with an inwardly concave shape (i.e., a dovetail arrangement as known in the art) may be preferred for additional mounting stability, etc.

[0049] Therefore, according to a third aspect of the subject matter of this application, a square bar stripping blade is provided, comprising: a first rake face and a second rake face positioned opposite thereto; a blade peripheral surface connecting the first rake face and the second surface; and a first cutting edge extending along the intersection of the blade peripheral surface and the first rake face; the blade peripheral surface includes a first peripheral sub-surface, a second peripheral sub-surface, a third peripheral sub-surface, and a fourth peripheral sub-surface, and a first corner, a second corner, a third corner, and a fourth corner connecting the first peripheral sub-surface, the second peripheral sub-surface, the third peripheral sub-surface, and the fourth peripheral sub-surface; wherein, in a plan view of the first rake face, between each adjacent pair of the first corner, the second corner, the third corner, and the fourth corner, the first cutting edge includes: a straight scraper edge defining an imaginary square together with other scraper edges of the same cutting edge; and a single stripping edge connecting an adjacent scraper edge to an adjacent corner; wherein the second rake face is mirror-symmetrical to the first rake face.

[0050] For example, the above construction can give the bar stripping blade a similar appearance to DE 298 15 761 U1. Figure 1 The cutting edge shape shown is the cutting edge shape on both rake faces of the bar stripping insert. For example, this can be accomplished using a negative arrangement structure or an inwardly concave shape along the peripheral surface, as illustrated below.

[0051] While it may seem trivial to simply make the two opposing rake faces of a single cutting insert identical, in this particular case, it will result in one side of the insert becoming a left-oriented insert and the other a right-oriented insert (the specific names here are not important, rather than, as mentioned above, one rake face being suitable only for a left-side insert holder and the other only for a right-side insert holder). Therefore, this will only be considered in retrospect in the recognition of the versatility of this insert in the production of different insert holders. For the end user, this insert does not have more cutting edges than DE 298 15 761 U1, but it offers only advantages for the manufacturer.

[0052] In any case, it is clear that the foregoing aspect is more advantageous than the third aspect, which itself is advantageous in a particular way over the known prior art.

[0053] It is worth noting that while the preferred embodiment of the bar stripping blade shown below is configured with screw holes, which is preferred for all aspects above, it will be understood that an alternative option is to make the bar stripping blade without screw holes and to clamp it, for example, using a top clamping member as known in the art. Nevertheless, it is preferred that the bar stripping blade include screw holes extending through the first rake face and the second surface.

[0054] According to a fourth aspect of the subject matter of this application, a square bar stripping insert is provided, comprising: a first rake face and a second surface positioned opposite thereto; an insert axis (As) extending through the center of both the first rake face and the second surface; an insert peripheral surface connecting the first rake face and the second surface, the insert peripheral surface including a first peripheral sub-surface, a second peripheral sub-surface, a third peripheral sub-surface, and a fourth peripheral sub-surface, and a first corner, a second corner, a third corner, and a fourth corner connecting adjacent peripheral sub-surfaces; and a first cutting edge extending along the intersection of the insert peripheral surface and the first rake face, the first cutting edge including sub-cutting edges located between each pair of adjacent corners; wherein, in a plan view of the first rake face, each sub-cutting edge includes: a centrally positioned straight... The scraper edge; and a first peeler edge and a second peeler edge located on opposite sides of the scraper edge; the first peeler edge is at least partially curved and connects the scraper edge to the first corner edge of a first corner in one of the plurality of pairs of adjacent corners; the second peeler edge is at least partially curved and connects the scraper edge to the second corner edge of a second corner in the same pair of adjacent corners as the first corner; in the plan view of the first front blade face: a straight scraper edge positioned in the center defines an imaginary square (S) that demarcates the blade; the first corner, the second corner, the third corner and the fourth corner are spaced inward from the imaginary square; the sides of the imaginary square have blade side lengths SL; and the scraper edge has a scraping length WL.

[0055] The preferred but optional features of the bar stripping blade according to any aspect above are as follows.

[0056] The second surface is preferably a rake face, which includes a cutting edge (hereinafter also referred to as the "second cutting edge") at its intersection with the peripheral surface of the insert. The chip forming groove or configuration may preferably extend adjacent to the cutting edge.

[0057] In the plan view of the first rake face: each of the first corner, second corner, third corner and fourth corner is preferably positioned inwardly spaced from the imaginary square.

[0058] When the second surface is the rake face, in its plan view: Each of the first corner, the second corner, the third corner, and the fourth corner is preferably positioned inwardly spaced apart from a hypothetical square formed by the wiper edge of the second surface.

[0059] The peripheral surface of the blade preferably extends perpendicular to both the first rake face and the second surface.

[0060] Preferably, the stripper edge includes a main sub-edge connected to the wiper edge, and an auxiliary sub-edge connected to the main sub-edge on one side thereof and to the corner on the other side thereof; wherein, in the plan view of the rake face on which the stripper edge is located, the main sub-edge is more curved than the auxiliary sub-edge. Preferably, each of the first stripper edge and the second stripper edge of the bar stripping blade includes the main sub-edge and the auxiliary sub-edge, wherein each corresponding main sub-edge is more curved than the adjacent auxiliary sub-edge.

[0061] For explanation, as mentioned, bar stripping is a very rough machining operation, and thus a curvature as large as possible (extending from the straight wiper edge) is desired to prevent breakage. However, this curvature also increases the rake angle K and thus the load on the stripper edge. Therefore, preferably, the auxiliary sub-edge is straighter than the main sub-edge, most preferably straight, resulting in a lower rake angle K. This has allowed the preferred embodiments to have a rake angle K that satisfies the following conditions: 15° < K < 25°, more preferably 18° < K < 22°.

[0062] Preferably, in the plan view of the rake face, the auxiliary sub-edge is straight.

[0063] It will be understood that both the stripper edge and the wiper edge are functional and need to be balanced. Preferably, in the plan view of the rake face, the length of one side of the hypothetical square defines the side length SL of the blade, and the length of each wiper edge in the same view defines the wiper length WL; wherein, the blade satisfies the following conditions: WL / SL < 0.6, more preferably WL / SL < 0.5, and most preferably WL / SL < 0.45. Nevertheless, it is believed to be advantageous that the wiper length WL is not overly small so that no beneficial surface finishing / stabilizing effect can be provided. Therefore, preferably, the blade satisfies the following conditions: WL / SL > 0.20, more preferably WL / SL > 0.30, and most preferably WL / SL > 0.35.

[0064] For a larger operating length on the blade side, the corner size can be reduced. Preferably, each corner has a corner radius smaller than either the first peeler edge or the second peeler edge. Since the main edges have a smaller radius than the auxiliary edges, it is preferable that each corner has a corner radius smaller than either of the main edges.

[0065] In the planar view of the first rake face, the length of one side of the imaginary square defines the blade side length SL, and the length of each peeler edge in a direction parallel to an adjacent side of the imaginary square defines the peeling length PL; wherein, preferably, the blade satisfies the condition: PL / SL < 0.3, more preferably PL / SL < 0.25. The peeler edges are functional and preferably should not be excessively small. Therefore, preferably, the blade satisfies the condition: PL / SL > 0.10, more preferably PL / SL > 0.15.

[0066] Preferably, at least one of the first cutting edge and the second cutting edge, and more preferably both, are rotationally symmetrical about a cutting edge axis extending through the center of both the first rake face and the second surface at 90°.

[0067] In view of the above explanation, according to a fifth aspect of the subject matter of this application, a bar stripping blade is provided, comprising: a cutting edge; wherein, along one side of the bar stripping blade defined between first and second adjacent corners, the cutting edge includes: a straight scraping edge and a first stripping edge connecting the scraping edge to the first corner; the scraping edge is longer than the first stripping edge, and wherein the stripping edge includes a main sub-edge connected to the scraping edge and an auxiliary sub-edge connected to the main sub-edge on one side and connected to the corner on the other side; and wherein the main sub-edge is more curved than the adjacent auxiliary sub-edge.

[0068] The preferred but optional features of the bar stripping blade according to any aspect above are as follows.

[0069] Preferably, in the plan view of the rake face of the bar stripping insert, the auxiliary sub-edge is straight. This allows for a relatively small, but not excessively small, lead angle.

[0070] Although the curved master edge may include multiple different curvatures, it is preferred to include a single curvature (i.e., radius) for ease of manufacture.

[0071] Preferably, as detailed above and for the reasons explained above in connection with the bar stripping operation, the scraping length WL is significantly longer than the stripping length PL. Preferably, the blade satisfies the condition that PL / WL < 0.75, more preferably PL / WL < 0.65. The stripping edge is functional and preferably should not be overly small. Therefore, preferably the blade satisfies the condition: PL / WL > 0.35, more preferably PL / WL > 0.45.

[0072] Since preferably the stripping edge is firm, it is preferably mostly curved. Thus, preferably the length of the main sub-edge, i.e., the main length P1L, is longer than the length of the auxiliary sub-edge, the auxiliary length P2L. In other words, preferably, P2L / P1L < 0.50, more preferably P2L / P1L < 0.40. Nevertheless, in order to obtain the advantages of a small front angle, the length of the auxiliary sub-edge must be significant. Therefore, preferably: P2L / P1L > 0.20, more preferably P2L / P1L > 0.30.

[0073] Preferably, the front angle K satisfies the condition: 15° < K < 25°, more preferably 18° < K < 22°.

[0074] Although this particular cutting edge design is considered to be independently creative, it can obviously be combined with any of the previous bar stripping blade aspects above for even more benefits.

[0075] According to a sixth aspect of the subject matter of the present application, there is provided a bar stripping blade holder comprising: a shank portion and a cutting portion; the cutting portion includes a first blade groove and a second blade groove that open outwardly in the same direction; each of the first blade groove and the second blade groove includes a groove base surface and a first groove side surface and a second groove side surface extending from the groove base surface; wherein, in a plan view of each respective groove base surface: the first groove side surface and the second groove side surface define two sides of a hypothetical square; and the hypothetical square of each groove base surface is rotated relative to the hypothetical square of the other groove base surface.

[0076] As will become clear below, the versatile design of the bar stripping blade allows it to be used as both a roughing bar stripping blade and a finishing bar stripping blade.

[0077] Although FR 2 483 819 seems to show an embodiment in which the same blades are used together, the lack of a significant scraping edge seems to be the reason for using three blade grooves instead of only two grooves in this aspect. And even in the case of three blades, it is believed that the scraping edge of the present invention will provide better surface finishing and other advantages (such as a relatively long cutting edge, and additional edges for each blade).

[0078] Given that the bar stripping blade is square, the blade groove can have a corresponding shape. Preferably, the first groove side surface and the second groove side surface of each of the corresponding first blade groove and second blade groove extend along the adjacent sides of the imaginary square.

[0079] The first blade recess (i.e., the blade recess intended to hold the roughing bar stripping blade) may preferably include a third recess side surface extending from the recess base surface, wherein, in a plan view of the recess base surface of the first blade recess, the third recess side surface defines the sides of the imaginary square of the first blade recess. It is noteworthy that, in this preferred but non-limiting embodiment, the third recess side surface is not used to abut the bar stripping blade, and therefore is added only to protect the bar stripping blade from damage. However, it is conceivable that different abutment arrangements in which the bar stripping blade abuts the third recess side surface may be utilized.

[0080] Preferably, the second blade groove (i.e., the blade groove designed to hold the finishing bar stripping blade) includes a third groove side surface extending from the groove base surface, wherein, in a plan view of the groove base surface of the second blade groove, the third groove side surface defines the sides of the imaginary square of the second blade groove.

[0081] Preferably, one of the first groove side surface and the second groove side surface of the second blade groove is parallel to the elongation direction of the blade holder.

[0082] As is known in the art, a shim can be used to protect the blade holder from damage when the bar stripper breaks. Preferably, the shim is made of a material harder than the blade holder, typically a sintered carbide.

[0083] During the development of this invention, a standard gasket design with the bushing coaxial with the screw hole of the blade was considered a second-best option compared to the following design concept.

[0084] Due to the unusually large size of the bar stripping insert compared to cutting inserts used in other machining operations, there is sufficient space to provide a recessed base surface having a centrally positioned screw hole for the bar stripping insert, and two additional washer screw holes spaced apart from the centrally positioned screw hole. Since the washer screw holes are not centrally positioned, it is preferable that there be more than one washer screw hole to provide stability. While this may seem less elegant than a single centrally positioned screw hole for both the cutting insert and the washer, and requires additional parts such as two separate screws for individually securing the washer, it is a preferred design unknown to the inventors to date, reducing the need for relatively complex washer components.

[0085] Preferably, the first blade groove and the second blade groove are both surrounded, and at least one of the groove base surfaces is formed with a centrally positioned screw hole and two washer screw holes spaced apart from the centrally positioned screw hole.

[0086] Therefore, according to a seventh aspect of the subject matter of this application, a blade holder is provided, which includes a blade recess having a recessed base surface formed with a centrally positioned screw hole and two washer screw holes spaced apart from the centrally positioned screw hole.

[0087] According to an eighth aspect of the subject matter of this application, a flat gasket is provided, comprising opposing first gasket sides and second gasket sides, and a gasket peripheral edge connecting the first gasket side and the second gasket side; the gasket is further formed with a centrally located screw hole and two gasket screw holes spaced apart from the centrally located screw hole. Preferably, the screw hole is larger in diameter than each of the two gasket screw holes.

[0088] According to a ninth aspect of the subject matter of this application, a tool assembly is provided, comprising a blade holder according to a sixth or seventh aspect and at least one gasket according to an eighth aspect.

[0089] According to a tenth aspect of the subject matter of this application, a bar stripping tool assembly is provided, comprising a blade holder according to any one of the sixth or seventh aspects, and at least one bar stripping blade according to any one of the first to fifth aspects.

[0090] It will be understood that the bar stripping tool assembly may also preferably include a gasket according to aspect eight.

[0091] Preferably, the bar stripping tool assembly includes two (first and second) bar stripping aspects according to the aspects described above, which are respectively mounted in the first and second blade recesses of the blade holder.

[0092] Preferably, the first blade is oriented such that at least one peeler edge and scraper edge on one side of the bar stripping blade are positioned to contact the bar workpiece, and the second blade is oriented such that at least one scraper edge is positioned to contact the bar workpiece, the scraper edge of the second blade being positioned substantially parallel to the elongation direction of the bar.

[0093] Preferably, the first blade is oriented such that both the first peeler edge and the second peeler edge, as well as the scraper edge, are positioned to contact the bar workpiece.

[0094] Preferably, the second blade is oriented such that its first peeling edge, which is positioned closer to the first blade than its second peeling edge, is positioned to contact the bar workpiece.

[0095] Preferably, the second blade is oriented such that its second peeler edge is positioned to not contact the bar workpiece.

[0096] It will be understood that the blades referred to in the specification and claims are bar stripping blades, and the term "blade" is used only occasionally for the sake of brevity when the preceding term "bar stripping" is not used. Similarly, the terms "blade holder" or "assembly" may appear in abbreviated form. The only exception to this statement relates to the gasket aspect and the related blade holder and assembly aspect, which is believed to be an advantageous design for cutting blades, even if it is not related to bar stripping. Attached Figure Description

[0097] To better understand the subject matter of this application, and to show how it can be implemented in practice, reference will now be made to the accompanying drawings, in which:

[0098] Figure 1 This is a perspective view of a tool assembly according to an inventive aspect of the invention;

[0099] Figure 2A This is a separate inventive aspect of the invention and is also used for Figure 1 A perspective view of the pads in the tool component;

[0100] Figure 2B yes Figure 2A A plan view of the gasket in the middle;

[0101] Figure 3A This is an inventive aspect of the invention and is also used for Figure 1 A perspective view of the bar stripping blade in the tool assembly;

[0102] Figure 3B yes Figure 3A A plan view of a blade and an imaginary dashed square;

[0103] Figure 3C yes Figure 3A A side view of the blade in the image;

[0104] Figure 3D It is along Figure 3B A cross-sectional view taken from the lines in IIID-IIID;

[0105] Figure 4A This is an inventive aspect of the invention and is also used for Figure 1 A perspective view of a portion of the blade holder in the tool assembly, with imaginary shading used to indicate the intended adjacent area;

[0106] Figure 4B yes Figure 4A The blade holder portion and the plan view of the imaginary dashed square;

[0107] Figure 4C yes Figure 4A A side view of the blade in the image;

[0108] Figure 5A yes Figure 1 The side perspective view of the tool components in the document; and

[0109] Figure 5B This is a schematic illustration of performing a bar stripping operation on a bar workpiece. Figure 5A A near-planar view of a portion of the components (i.e., slightly not perpendicular to the top surface of the blade holder, as will be explained below). Detailed Implementation

[0110] refer to Figure 1 The diagram shows a bar stripping tool assembly 10. Assembly 10 includes: a blade holder 12; and two identical blades 14, 16, which serve as a roughing blade 14 and a finishing blade 16 in the blade holder 12 with their respective positions and orientations; and identical first shims 18 and second shims 20, which are respectively located between the roughing blade 14 and the finishing blade 16 and their respective first blade recesses 22 and second blade recesses 24 into which they are mounted.

[0111] The roughing insert 14 is secured to the first insert recess 22 by a screw 26. Similarly, the finishing insert 16 is secured to the second insert recess 22 by another screw 28.

[0112] Also refer to Figure 2A , Figure 2B , Figure 3A and Figure 4A Only the first gasket 18 of these two identical gaskets will be described.

[0113] The first gasket 18 is made of sintered carbide and has a planar (or in other words, plate) shape. More specifically, the first gasket 18 includes opposing first gasket sides 30 and second gasket sides 32, as well as a gasket peripheral edge 34.

[0114] The first washer 18 is formed with a centrally positioned screw hole 36 and two washer screw holes 38 and 40 separated from the centrally positioned screw hole.

[0115] Since the centrally located screw hole 36 is used for the larger screw 26 (due to the greater force on the roughing insert 14 (or even the finishing insert 16), it has a diameter greater than that of each of the two washer screw holes 38, 40.

[0116] During assembly, two separate screws (not shown) are used to secure the first washer to the threaded first washer screw hole 38 and second washer screw hole 40 formed in the first blade recess 22. However, standard screws are selected (constructed) to be flush with or below the first washer side to avoid interfering with the stable installation of the roughing blade 14.

[0117] With the first washer 18 secured, the roughing insert 14 can then be secured to the first insert groove 22 using screws 26.

[0118] Now for reference Figures 3A to 3D The roughing insert 14 will be described in detail (similar to a shim, only one of the two identical inserts will be described, namely the roughing insert 14).

[0119] The roughing insert 14 includes a first rake face 42 and a second surface 44 (also referred to as the "second rake face" 44 in this example, where a plan view is not shown because the second surface 44 is...) Figure 3B The first rake face 42 is the same as the first rake face 42 in the diagram, and the peripheral surface 46 of the insert connects the first rake face 42 and the second surface 44. Since the first rake face 42 and the second surface 44 are the same, only the first rake face 42 will be described in detail.

[0120] Depending on the different views, it will be understood that the peripheral surface 46 of the insert extends perpendicularly to both the first rake face 42 and the second surface 44, and therefore the roughing insert 14 is a so-called negative cutting insert.

[0121] The roughing insert 14 comprises four identical sides, of which only one will be described in detail.

[0122] For the sake of detail, the blade peripheral surface 46 can be considered as including a first peripheral sub-surface 48, a second peripheral sub-surface 50, a third peripheral sub-surface 52 and a fourth peripheral sub-surface 54, and a first corner portion 56, a second corner portion 58, a third corner portion 60 and a fourth corner portion 62 connecting the first peripheral sub-surface 48, the second peripheral sub-surface 50, the third peripheral sub-surface 52 and the fourth peripheral sub-surface 54.

[0123] The roughing insert 14 includes a screw hole 64 extending through the center of the first rake face 42 and the second surface 44. As mentioned above, such a bar stripping insert can alternatively be a solid insert (i.e., without a screw hole) if a different clamping method is desired.

[0124] The first cutting edge 66 extends along the intersection of the insert peripheral surface 46 and the first rake face 42. In this preferred example, the first cutting edge 66 extends along the entire insert peripheral surface 46.

[0125] More precisely, the first cutting edge 66 includes a first sub-cutting edge 68 adjacent to the first peripheral sub-surface 48, a second sub-cutting edge 70 adjacent to the second peripheral sub-surface 50, a third sub-cutting edge 72 adjacent to the third peripheral sub-surface 52, and a fourth sub-cutting edge 74 adjacent to the fourth peripheral sub-surface 54.

[0126] Since the roughing insert 14 can be indexed in four directions (90°), only the first sub-cutting edge 68 will be described in detail.

[0127] Plan view of the first rake face 42 (i.e., Figure 3B In the first sub-cutting edge 68, there are: a straight scraping edge 76 positioned in the center; a first peeling edge 78 connected to the first corner 56 (or more precisely, to the first corner edge 80 formed at the intersection of the first corner 56 and the first front blade face 42) on one side; and a second peeling edge 82 connected to the second corner 62 (or more precisely, to the second corner edge 84) on the other side.

[0128] Note that all peeler edges are identical, with the first peeler edge 78 including a main sub-edge 86 connected to the scraper edge 76 and an auxiliary sub-edge 88 connected to the first corner 56 (or more precisely, to the first corner edge 80).

[0129] Preferably, the primary edge 86 is more curved than the secondary edge 88 (which is straight in this preferred example) (in the plan view shown in FIG3).

[0130] like Figure 3B As shown, both the first peeling edge and the second peeling edge are about the plane P. M (Its extension passes through the center of the blade, and more precisely, through the center of the scraper edges of the sub-cutting edges 72, 76 seen on the opposite side of the first rake face 42) The center C of the bisected scraper edges 76 is mirror-symmetrical.

[0131] It is worth noting that the blade axis A, which is also used as the axis of the screw hole, S Extends through the center of screw hole 64 and lies in plane P M middle.

[0132] The roughing insert 14 has its axis A about the first rake face 42 and the second rake face 44. S It has 90° rotational symmetry. Therefore, on each side, the roughing insert 14 has a relative to the screw hole axis A. S Four-way rotational indeterminateness.

[0133] Returning to the first cutting edge 66, preferably, all cutting edges are positioned adjacent to a chip forming arrangement such as groove 90, which in this preferred example extends adjacent to the entire cutting edge 66.

[0134] like Figure 3B As seen, each of the scraper edges 76 forms an imaginary square S, that is, all four scraper edges are located on different sides of the imaginary square.

[0135] For completeness, it is worth noting that not only the scraper edges on the first rake face, but also similar imaginary squares (not shown) will exist in the same view (not shown) of the second surface, and a portion of the blade periphery surface between the scraper edges on the first and second surfaces will indeed fall within the plane connecting these two imaginary squares. Thus, the eight scraper edges (four associated with each rake face) are considered to have negative (or at least neutral) geometry.

[0136] Furthermore, the first cutting edge 66, or more precisely, its scraper edge 76, defines an inscribed circle IC with a diameter D. In this preferred example, the diameter D is approximately 35 mm.

[0137] The diameter D is also equal in length to the blade side length SL of the imaginary square S.

[0138] It is worth noting that the scraping length WL is longer than the peeling length PL.

[0139] In this preferred example, the shaving length WL is approximately 14 mm.

[0140] In this preferred example, the peel length PL is approximately 8 mm.

[0141] It should also be noted that, in the preferred embodiment, the length of the blade edge SL is still greater than, or even twice, the sum of the scraping length WL and the peeling length PL.

[0142] Similarly, the primary length P1L associated with the primary sub-edge 86 is preferably longer than the secondary length P2L associated with the secondary sub-edge 88.

[0143] In this preferred example, the main length P1L is approximately 6 mm.

[0144] In this preferred example, the auxiliary length P2L is approximately 2 mm.

[0145] Now for reference Figure 1 The blade holder 12 includes a shank portion 92 and a cutting portion 94.

[0146] refer to Figures 4A to 4C The cutting section 94 will be described in more detail.

[0147] As mentioned above, in a preferred embodiment, the cutting portion 94 includes a first blade groove 22 and a second blade groove 24 that open outward in the same direction.

[0148] The first blade groove 22 includes a groove base surface 96 and circumferentially adjacent first groove side surface 98 and second groove side surface 100 extending from the groove base surface 96. (Plan view of the surface of the groove base surface 96) Figure 4B In the first groove side surface 98 and the second groove side surface 100, the first imaginary square S1 has two adjacent circumferential sides defined.

[0149] All the adjacent surfaces of the grooves of the first blade groove 22 (in) Figure 4A (Shown schematically in shading) Formed on the first groove side surface 98 and the second groove side surface 100.

[0150] Specifically, the first groove side surface 98 includes a first groove abutment surface 102 adjacent to the front end 104 of the blade holder 12 in this preferred embodiment. Although not easily visible, the adjacent region 106 of the first groove side surface 98 is slightly recessed behind the first groove abutment surface 102 to ensure contact between the roughing blade 14 and the intended abutment region, i.e., the first groove abutment surface 102.

[0151] Additionally, the second groove side surface 100, which is the groove side surface furthest from the front end 104, includes a second groove adjacent surface 108 and a third groove adjacent surface 110 separated by the gap recess 112.

[0152] The first blade groove 22 also includes a third groove side surface 114, which in this non-limiting embodiment is intended to avoid contact with the roughing blade 14.

[0153] Therefore, in the preferred arrangement shown, the roughing blade 14 only contacts the groove base surface 96 (or more precisely, in this embodiment including the gasket, the first gasket 18, which in turn contacts the groove base surface 96) and only the first groove adjacent surface 102, the second groove adjacent surface 108, and the third groove adjacent surface 110.

[0154] It will be understood that different adjacent arrangement structures may be conceivable, including adjacent surfaces on the third recess side surface 114.

[0155] The second blade groove 24 is essentially the same as the first blade groove 22, and will therefore be described only briefly.

[0156] The second blade groove 24 includes a groove base surface 116, a first groove side surface 118 and a second groove side surface 120 that are circumferentially adjacent to the two sides of the second imaginary square S2. (Plan view of the cutting portion 94 of the blade holder) Figure 4B In the first blade groove 24, the groove base surface 116 of the second blade groove 24 and the groove base surface 96 of the first blade groove 22 face the same direction. However, in the plan view, the angular orientation of the first groove 22 is different from that of the second groove 24. Therefore, correspondingly, the imaginary squares S1 and S2 of the two grooves 22 and 24 are rotated relative to each other in the plan view, and this rotation is about the center of the corresponding imaginary square S1 or S2.

[0157] All the adjacent surfaces of the grooves in the second blade groove 24 (in) Figure 4A (Shown schematically in shading) Formed on the first groove side surface 118 and the second groove side surface 120.

[0158] Specifically, the first groove side surface 118 includes a first groove adjacent surface 122. The second groove side surface 120 includes a second groove adjacent surface 124 and a third groove adjacent surface 126 separated by a gap recess 128.

[0159] The second blade groove 24 also includes a third groove side surface 129, which in this non-limiting embodiment is intended to avoid contact with the finishing blade 16.

[0160] Therefore, in the preferred arrangement shown, the finishing blade 16 only contacts the groove base surface 116 (or more precisely, in this embodiment including the gasket, the second gasket 20, which in turn contacts the groove base surface 116) and only the first groove adjacent surface 122, the second groove adjacent surface 124 and the third groove adjacent surface 126.

[0161] Corresponding to the first washer 18, the groove base surface 96 of the first blade groove 22 is formed with a centrally positioned threaded screw hole 130 and two threaded washer screw holes 132, 134 separated from the centrally positioned screw hole 130 (where the corresponding structure is formed in the second blade groove 24).

[0162] The third recess side surface 114, or more precisely, the first recess wall 114A of the first blade recess 22 including the third recess side surface 114, is not used for adjacency and is therefore not necessary. Nevertheless, it provides the protective function as described above.

[0163] For completeness, the second wall 98A separates the first blade recess 22 and the second blade recess 24, and includes a first recess side surface 98 of the first blade recess 22 and a third recess side surface 129 of the second blade recess 24 on the opposite side.

[0164] Additionally, the third wall 118A includes the first groove side surface 118 of the second blade groove 24.

[0165] Regarding the rotational positions of the first blade recess 22 and the second blade recess 24, it should be noted that the second adjacent surface 124 and the third adjacent surface 126 of the second blade recess 24 (and the second recess side surface 120 formed thereon) are substantially perpendicular to the extension direction of the blade holder 12 (by the extension axis A). E limited).

[0166] In order to limit the angular rotation of the groove in an alternative manner, in the plan view of the cutting portion 94 of the blade holder 12 ( Figure 4B In the first blade recess 22, a first normal N1 is perpendicular to the second recess side surface 100 of the blade (and more precisely, perpendicular to its second recess adjacent surface 108 and third recess adjacent surface 110) and bisects the first imaginary square S1. Simultaneously, a second blade recess 24 has a second normal N2 perpendicular to the second recess side surface 120 of the blade (and more precisely, perpendicular to its second recess adjacent surface 124 and third recess adjacent surface 126) and bisects the second imaginary square S2. The first normal N1 and the second normal N2 form an acute angle α. In some embodiments, the angle α is between 30° and 50° (i.e., 30° ≤ α ≤ 50°) and preferably: 35° ≤ α ≤ 45°. The second normal N2 may be parallel to the elongation axis A of the blade holder 12. E .

[0167] refer to Figure 5B The description of the bar stripping tool assembly 10 in the elongation direction D E The operation on the bar 136. In this figure, a cutting blade is placed in each blade groove, wherein the operating sub-cutting edge of the blade (in this example, sub-cutting edge 68) engages the bar 136.

[0168] As described above, the roughing insert 14 and the finishing insert 16 are negative inserts, and therefore, preferably, the insert holder 12 provides a clearance with a negative orientation, which is visible due to the fact that the peripheral insert surface 46 is slightly visible.

[0169] The roughing insert 14 is oriented to provide roughing functionality (removing a large amount of material) such that the entire first operational sub-cutting edge 68 (i.e., both the scraper edge 76 and the first peeler edge 78 and the second peeler edge 82) engages the bar 136 to achieve a cutting depth A P1 Remove the material from it.

[0170] It should be understood that the cutting depth A P1Very large, and of course, if the force on the roughing insert 14 is too great in a particular application, the depth of cut A can be reduced by using less of the second peeler edge 82 to engage the workpiece. P1 .

[0171] However, the second corner 62 was not joined due to its sharp and therefore relatively fragile construction.

[0172] Nevertheless, it will be understood that by using the subsequent indexing of the roughing insert 14, its entire cutting edge is actually utilized.

[0173] Similarly, the finishing insert 16 is oriented to remove less material (note that when combined with the depth of cut A) P1 For comparison, the cutting depth A is relatively much smaller. P2 The finishing function is provided using only one peeler edge (second peeler edge 82) and scraper edge 76 of the joining bar 136.

[0174] Similarly, the second corner 62 was not joined, and of course, the first corner 56 was not joined either.

[0175] It is worth noting that the scraper edge 76 of the finishing blade 16 is substantially aligned with the elongation direction D of the bar. E It is parallel, and therefore provides not only a wiping function, but also a stabilizing function as described above.

[0176] The foregoing description includes exemplary embodiments, and does not exclude embodiments and details not illustrated from the scope of the claims of this application.

Claims

1. A square bar stripping blade, comprising: The first rake face and the second surface positioned opposite it; The blade axis (As) extends through the center of both the first rake face and the second surface; The blade peripheral surface connects the first rake face and the second surface. The blade peripheral surface includes a first peripheral sub-surface, a second peripheral sub-surface, a third peripheral sub-surface, and a fourth peripheral sub-surface, as well as a first corner, a second corner, a third corner, and a fourth corner connecting adjacent peripheral sub-surfaces. as well as A first cutting edge extends along the intersection of the peripheral surface of the blade and the first rake face, and the first cutting edge includes sub-cutting edges between each pair of adjacent corners; In the planar view of the first rake face, each sub-cutting edge includes: A straight, centered edge for the scraper; and The first peeler edge and the second peeler edge are located on opposite sides of the edge of the scraper; The first peeler edge is at least partially bent, and the scraper edge is connected to the first corner edge of the first corner of one of the pairs of adjacent corners; The second peeler edge is at least partially curved, which connects the scraper edge to the second corner edge of the second corner of a pair of adjacent corners that are the same as the first corner; In the plan view of the first rake face: The straight edge of the centrally positioned squeegee is defined as an imaginary square bounded by the blade. The first corner, the second corner, the third corner, and the fourth corner are separated inward from the imaginary square; The imaginary square has a blade-length side SL; The edge of the squeegee has a squeegee length WL; Each of the first peeling edge and the second peeling edge includes a main sub-edge connected to the scraping edge and an auxiliary sub-edge connected to the main edge on one side and to the corner on the other side; Wherein, the first peeler edge has a length PL measured parallel to the straight scraper edge; The main edge has a main length P1L measured parallel to the straight scraper edge; The auxiliary sub-edge has an auxiliary length P2L measured parallel to the straight squeegee edge, where PL = P1L + P2L; and The main length P1L is longer than the auxiliary length P2L.

2. The square bar stripping blade according to claim 1, wherein, The blade is double-sided and also includes a second cutting edge extending along the intersection of the peripheral surface of the blade and the second surface.

3. The square bar stripping blade according to claim 1, wherein, The leading angle (K) formed between the straight scraper edge and the auxiliary sub-edge satisfies the condition 15° < K < 25°.

4. The square bar stripping blade according to claim 2, wherein, The second cutting edge includes sub-cutting edges located between each pair of adjacent corners; wherein, in a plan view of the second surface, each sub-cutting edge includes: a centrally located straight squeegee edge; and a first peeling edge and a second peeling edge located on opposite sides of the squeegee edge; the first peeling edge is at least partially curved and connects the squeegee edge to a first corner edge of a first corner in one of the pairs of adjacent corners; and the second peeling edge is a second peeling edge that is at least partially curved and connects the squeegee edge to a second corner edge of a second corner in the same pair of adjacent corners as the first corner.

5. The square bar stripping blade according to claim 1, wherein, The peripheral surface of the blade extends perpendicularly to both the first rake face and the second surface.

6. The square bar stripping blade according to claim 1, wherein, In the plan view, the primary edge is more curved than the secondary edge.

7. The square bar stripping blade according to claim 6, wherein, In the plan view, the auxiliary sub-edge is straight.

8. The square bar stripping blade according to claim 1, wherein, The blade meets the following condition: WL / SL < 0.

6.

9. The square bar stripping blade according to claim 8, wherein, The blade meets the following condition: WL / SL > 0.

20.

10. The square bar stripping blade according to claim 1, wherein, Each corner has a corner radius smaller than either the first peeler edge or the second peeler edge.

11. The square bar stripping blade according to claim 6, wherein, Each corner has a corner radius smaller than any of the main edges.

12. The square bar stripping blade according to claim 1, wherein: The length of each peeler edge in the direction associated with one of the sides of the imaginary square defines the peeling length PL; and the blade satisfies the condition: PL / SL < 0.

3.

13. The square bar stripping blade according to claim 12, wherein, The blade meets the following condition: PL / SL > 0.

15.

14. The square bar stripping blade according to claim 1, wherein, The first cutting edge is rotationally symmetrical about the blade axis (As) by 90°.

15. The square bar stripping blade according to claim 3, wherein, The forward angle (K) satisfies the condition 18° < K < 22°.

16. The square bar stripping blade according to claim 1, wherein, 0.20 ≤ P2L / P1L ≤ 0.

50.

17. A bar stripping tool assembly comprising a bar stripping blade holder having a first blade groove and a second blade groove, and two square bar stripping blades according to any one of claims 1 to 16, wherein, The first square bar stripping blade and the second square bar stripping blade are respectively installed in the first blade groove and the second blade groove of the blade holder. The first square bar stripping blade has a first operable sub-cutting edge, and the second square bar stripping blade has a second operable sub-cutting edge.

18. The bar stripping tool assembly according to claim 17, wherein, The rod stripping tool assembly has an elongation direction (D) E The first square bar stripping blade and the second square bar stripping blade are both in contact with the bar workpiece; the first square bar stripping blade is oriented such that the scraper edge and at least one stripping edge of the first operational sub-cutting edge are in contact with the bar workpiece; the second square bar stripping blade is oriented such that at least one scraper edge of the second operational sub-cutting edge is in contact with the bar workpiece; and the scraper edge of the second operational sub-cutting edge is parallel to the elongation direction of the bar workpiece.

19. The bar stripping tool assembly according to claim 18, wherein, The two peeling edges of the first operational cutting edge contact the bar workpiece.

20. The bar stripping tool assembly according to claim 18, wherein, The second operational sub-cutting edge has a peeling edge that contacts the bar workpiece, and the peeling edge is closer to the first square bar peeling blade than the other peeling edge of the second operational cutting edge.

21. The bar stripping tool assembly according to claim 20, wherein, The other peeling edge of the second operational cutting edge does not contact the bar workpiece.

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