Tool holder adapter, pin for fastening to a tool holder adapter, tool, and tool fastening system

Abstract

The present invention relates to a tool holder adapter (10; 110) for fastening a tool (80; 180; 280) to a machine tool by means of a pin (50; 150; 250; 350; 450). The tool holder adapter (10; 110) has a neck structure (20) for inserting the pin (50; 150; 250; 350; 450), in which neck structure an inner recess (30) extends from a tool side (WS10) along a longitudinal axis (LA30). For robust and reliable fastening of a tool (80; 180; 280) and to facilitate high manufacturing precision, the inner recess (30) has, perpendicular to the longitudinal axis (LA30), a receiving cross-section whose basic shape corresponds to a polygon having at least five vertices (32), a hypocycloid having at least five vertices (32), a pericycloid or an epicycloid. The invention further relates to a matching pin (50; 150; 250; 350; 450) for fastening a tool (80; 180: 280) to a tool holder adapter (10; 110), a matching tool (80; 180; 280) and a tool fastening system having the tool holder adapter (10; 110) and the pin (50; 150; 250; 350; 450).

Description

[0001]

[0002] Tool holder adapter, pin for attachment to a tool holder adapter, tool and tool fastening system

[0003] The present invention relates to a tool holder adapter for attaching a tool to a machine tool by means of a pin, and to a pin for attaching a tool to a tool holder adapter. The present invention further relates to a suitable tool and a tool fastening system comprising the tool holder adapter and the pin.

[0004] In industrial production, rotating, essentially disc-shaped tools such as circular saw blades, disc cutters, and circular knives are used for material processing. Typically, the tool is attached to a tool holder on a suitable machine tool. The machine tool drives the tool attached to the tool holder, causing it to rotate around its central axis and be used for material processing. Many machine tools can also move their tool holder and the workpiece relative to each other. This allows for a controlled machining process using the tool.

[0005] To attach the tool to the machine tool, pins are sometimes used. While one end of the tool rests against the tool holder of the machine tool, the other end rests against the pin. The pin is in turn attached to the tool holder. The tool is held between the pin and the tool holder.

[0006] The tool's attachment to the tool connection should enable long tool life and low flatness and concentricity errors. Furthermore, the

[0007] August 29, 2025 N 30 P 9

[0008] Fasteners capable of transmitting high torques to the rotary drive of the tool.

[0009] The task is to propose components that facilitate a robust and reliable attachment of a tool to a machine tool, as well as the achievement of high manufacturing precision.

[0010] This problem is solved by a tool holder adapter having the features of claim 1.

[0011] The tool holder adapter is used to attach a tool to a machine tool by means of a pin, for example to a tool connection of the machine tool.

[0012] The tool holder adapter extends from one side of the machine to one side of the tool, in particular along a longitudinal direction, wherein the tool holder adapter

[0013] - has an adapter structure towards the machine side for attaching the tool holder to the tool connection and / or is attached to the machine tool and

[0014] - has a neck structure on the tool side.

[0015] The neck structure has an internal recess (for inserting the pin) that extends from the tool side along a longitudinal axis. This longitudinal axis can be parallel to the longitudinal direction.

[0016] The inner recess has a receiving cross-section perpendicular to the longitudinal axis, the basic shape of which corresponds to a polygon with at least five vertices, a hypocycloid with at least five vertices, a pericycloid or an epicycloid.

[0017] August 29, 2025 N 30 P 9

[0018] These basic shapes allow for the reliable transmission of particularly high torques to the rotary drive of the tool, especially with regard to the area of ​​the mounting cross-section and / or the size of the tool holder adapter. Furthermore, they allow for the reliable and precise positioning of a corresponding insertion element of a pin within the tool holder adapter. The internal recess is designed for a positive fit with the corresponding insertion element of the pin.

[0019] The present invention allows for the realization of very small flatness and concentricity errors. It enables long tool life. Nevertheless, tool replacement is simple, quick, and safe. The positioning of the tool relative to the machine tool is very accurate and precisely reproducible.

[0020] The tool holder adapter can be attached to the machine tool, more precisely to the tool port of the machine tool. However, the tool holder adapter can also be permanently attached to the machine tool, in other words, it can be integrally formed with the machine tool (or a part of the machine tool).

[0021] The inner recess has a lateral surface that defines the receiving cross-section (in a radial direction). Accordingly, this lateral surface has the aforementioned basic shape in a cross-section perpendicular to the longitudinal axis.

[0022] From one perspective, the basic shape of the receiving cross-section can correspond to a polygon with at least five vertices or an elongated hypocycloid with at least five vertices. This allows for the reliable transmission of high torques in a small installation space. At the same time, manufacturing is simple.

[0023] August 29, 2025 N 30 P 9

[0024] These basic shapes enable self-centering with respect to runout errors. Furthermore, load-bearing capacity (with regard to torque transmission to the journal) is distributed particularly well, especially under high loads and / or when elastic deformation occurs.

[0025] Alternatively or additionally, the basic shape of the imaging cross-section can correspond to a polygon or a hypocycloid with a maximum of ten, e.g., with a maximum of seven rounded tips.

[0026] If the basic shape is a polygon, it can be a convex and / or regular polygon. This allows for simple yet precise manufacturing with low concentricity errors.

[0027] If the basic shape corresponds to a hypocycloid, it can be an elongated hypocycloid. This allows for simple yet precise manufacturing with low concentricity errors.

[0028] One, several, or all of the vertices (of the polygon / hypocycloid) can be rounded. This simplifies manufacturing and prevents the risk of something becoming wedged in the internal recess, for example, the insertion element of the pin. It allows for easier insertion and removal of the insertion element. Furthermore, rounding reduces the risk of local stress concentrations.

[0029] In particular, the basic shape of the recording cross-section can

[0030] - a regular polygon with exactly five or exactly six rounded vertices or

[0031] - corresponding to an elongated hypocycloid with exactly five or exactly six rounded tips. This ensures the best possible torque transmission for typical internal dimensions.

[0032] August 29, 2025 N 30 P 9

[0033] In one embodiment, the engagement means include at least one internal thread for a clamping screw. The at least one clamping screw serves to fix or secure the pin and / or the tool to the tool holder adapter.

[0034] For example, the engagement devices can include internal threads for multiple clamping screws.

[0035] In particular, the means of engagement can include at least one threaded hole for the clamping screw, and in a wider version, several threaded holes for clamping screws.

[0036] According to another aspect, at least one internal thread (or at least one threaded bore) of the engagement means can connect to the internal recess on the machine side along the longitudinal direction. Thus, the clamping screw can be brought into engagement with the internal thread through the internal recess.

[0037] In one embodiment, the neck structure has a cylindrical outer surface. The central axis of this cylindrical outer surface can coincide with the longitudinal axis of the inner recess. When the tool holder adapter is rapidly rotated by the machine tool, the cylindrical outer surface rotates uniformly in the circumferential direction. This reduces rotational resistance and minimizes the risk of injury and damage from collisions with the rotating outer surface. Unnecessary flinging of coolant by an irregular outer surface is avoided.

[0038] August 29, 2025 N 30 P 9

[0039] According to one aspect, the adapter structure can include a shaft. The machine connection can have a chuck. Accordingly, the shaft can be secured in the chuck.

[0040] Alternatively or additionally, the adapter structure can have at least one transverse groove on a machine-side end face of the adapter structure or the tool holder adapter. The transverse groove allows for a particularly simple and reliable transmission of torque from the machine connection to the tool holder adapter.

[0041] The adapter structure can be designed for mounting on a standardized machine connection. This improves compatibility with common machine tools. For example, the adapter structure can have features according to DIN 138 and / or DIN 1835. Alternatively or additionally, the adapter structure can have one, several, or all of the following features: an external thread, at least one mating circumferential surface (e.g., cylindrical and / or conical), and at least one axial stop surface. Furthermore, the adapter structure can have features of a clamping and / or expanding mechanism. The clamping and / or expanding mechanism can act radially inward or radially outward. It can be mechanical and / or hydraulic. In particular, the adapter structure can have a hydraulic expansion clamping mechanism.

[0042] In a further development, the tool holder adapter has at least one passage for coolant from the machine side into the inner recess. This allows coolant to flow from the machine tool to the inner recess. From there, it can be further distributed and / or flow out to the tool.

[0043] August 29, 2025 N 30 P 9

[0044] The tool holder adapter can have a machine-side internal bore extending longitudinally from the machine side. This internal bore can form part of the adapter structure. Alternatively or additionally, the machine-side internal bore and the internal recess can be fluid-connected. Due to this fluid connection, the internal bore can be used for the passage of coolant.

[0045] According to one aspect, at least one additional coolant recess can be provided on the outer surface of the inner recess, extending along the longitudinal direction and located in a region of the outer surface with the lowest torque transmission during operation. If the basic shape of the receiving cross-section of the inner recess corresponds to a (regular) polygon or an (extended) hypocycloid, the at least one coolant recess can be located in a central region of the outer surface between two adjacent points along the circumferential direction. The coolant recess can, for example, be parallel to the longitudinal axis of the inner recess or helically shaped.

[0046] The insertion element of the pin has a lateral surface whose basic shape (in a cross-section transverse to a longitudinal direction of the insertion element) corresponds to the basic shape of the receiving cross-section of the inner recess (and vice versa). The insertion element can be inserted into the inner recess. The lateral surface of the insertion element and the lateral surface of the inner recess then engage with each other in a form-fitting manner. There is essentially no clearance between the lateral surfaces (apart from a negligible mechanical play necessary for insertion and removal). Thus, no coolant could flow through the inner recess. By additionally providing at least one coolant recess in the lateral surface of the inner recess, a gap is created between the lateral surface of the insertion element and a circumferential wall of the

[0047] August 29, 2025 N 30 P 9

[0048] An internal recess provides a free space that allows the passage of coolant, particularly from the machine-side end of the internal recess to a tool-side end of the internal recess. Generally, the at least one coolant recess is configured such that it is not blocked when the insert element is inserted into the internal recess.

[0049] Furthermore, several coolant recesses can be formed in the outer surface of the inner recess. In particular, a number of these coolant recesses can correspond to a number of points of the basic shape of the receiving cross-section of the inner recess (for example, five or six). The coolant recesses can be arranged uniformly along the circumferential direction.

[0050] In one embodiment, the end face of the tool holder adapter is designed to be flat on the tool side. This allows for a clean and uniform contact between a portion of the machine-side (or adapter-side) end face of the tool and the end face of the tool holder adapter.

[0051] The tool holder adapter and the tool attached to it are rotated during operation, for example around the longitudinal axis of the inner recess of the tool holder adapter.

[0052] Optionally, at least one coolant outlet can be formed in the tool-side end face for radial discharge of coolant from the inner recess. This allows the coolant to cool the tool during operation. The coolant can exit from the inner recess of the tool holder adapter to the outside onto one machine side of the tool. Since the tool holder adapter and the tool attached to it rotate during operation...

[0053] August 29, 2025 N 30 P 9 The centrifugal force ensures that the coolant exits through at least one coolant outlet (or outlets) of the tool holder adapter and also flows radially outwards on the machine side of the tool. This cools the tool over its entire surface and also allows the coolant to penetrate radially outwards to a machining zone on the outside of the tool.

[0054] The at least one coolant outlet (of the tool holder adapter) can open into the inner recess in a region of the recess's outer surface where torque transmission (during operation) is lowest. Due to symmetries, there can be several such regions. The at least one coolant outlet can open into the inner recess along a circumferential direction in a central region between two successive peaks of the basic shape of the holder's cross-section. Little torque would be transmitted through this central region anyway. Therefore, the outer surface of the inner recess is preferably interrupted by the coolant outlet in this area.

[0055] One (radially inner) end of the coolant outlet can lead into at least one coolant recess.

[0056] Naturally, several coolant outlets can be formed in the tool-side end face for the radial discharge of coolant from the inner recess. In particular, a number of these coolant outlets can correspond to a number of peaks of the basic shape of the receiving cross-section of the inner recess (for example, five or six).

[0057] In particular, the number of coolant outlets can correspond to the number of coolant recesses.

[0058] August 29, 2025 N 30 P 9

[0059] In one embodiment, all coolant outlets (of the tool holder adapter) are designed and positioned identically. This ensures a more uniform flow of coolant. The coolant outlets can be evenly spaced along the circumferential surface. Each coolant outlet can be located in a central area between two successive peaks of the holder cross-section.

[0060] In this advanced design, each coolant outlet includes a recess in the tool-side end face (of the tool holder adapter) that, viewed along a radial direction of the tool holder adapter, widens outwards in a circumferential direction and / or narrows outwards in the longitudinal direction. This improves the distribution of coolant during operation.

[0061] The tool holder adapter may have a countersunk hole for a locking screw to secure the tool holder adapter to the machine connection. The tool holder adapter may also include the locking screw.

[0062] According to one aspect, the basic shape of the receiving cross-section can be formed rotating around the longitudinal axis of the inner recess. In other words, as the position along the longitudinal axis of the inner recess increases, the basic shape of the receiving cross-section rotates progressively further around the longitudinal axis, particularly concentrically. For example, grooves on the outer surface of the inner recess, formed by the tips of the basic shape of the receiving cross-section (optionally rounded), can run helically around the longitudinal axis (of the inner recess). The inner recess can thus be spirally formed along its longitudinal axis.

[0063] August 29, 2025 N 30 P 9

[0064] The above-mentioned problem is further solved by a pin for fastening a tool having the features of claim 13.

[0065] The embodiments and advantages described with regard to the tool holder adapter apply accordingly to the pin and vice versa.

[0066] The pin serves to attach a tool to a tool holder adapter, in particular according to the present invention.

[0067] The pin has an insertion element which extends along its longitudinal axis and has a lateral surface whose basic shape in a cross-section transverse to the longitudinal axis (of the insertion element) corresponds to a polygon with at least five vertices, a hypocycloid with at least five vertices, a pericycloid or an epicycloid.

[0068] The insertion element can form the "counter-element" to the inner recess of the tool holder adapter and vice versa.

[0069] The pin can be inserted into the internal recess easily, quickly, safely, and reliably. The pin, and especially the special shape of the insertion element, are relatively easy and inexpensive to produce. Nevertheless, production is possible with high accuracy and repeatability. Furthermore, the special shape of the insertion element allows for high torque transmission while simultaneously enabling easy insertion and removal of the insertion element from the internal recess of the tool holder adapter.

[0070] In a further development, the pin has at least one continuous countersunk bore that extends parallel to the longitudinal axis of the insertion element. This allows a clamping screw to be inserted through it. With the clamping screw

[0071] August 29, 2025 N 30 P 9 The pin can be attached to the tool holder adapter. The countersunk hole can form a contact surface for the screw head of the clamping screw.

[0072] The pin can encompass the tool (and vice versa). The pin can be integral with the tool. In another embodiment, the pin is a separate element from the tool and is designed to attach the tool, for example, at a tool-side end facing away from a machine-side end (along the longitudinal axis).

[0073] According to one aspect, the pin has a flange area at one end of the longitudinal axis of its insertion element. The flange area can include a contact surface for the tool, for example, for the tool to bear against the longitudinal direction (of the insertion element). In operation, the tool can bear against the flange area from the side of the insertion element. In particular, the tool can be mounted onto the insertion element so that the flange comes into contact with the tool on a side facing away from the machine.

[0074] In a further development, the flange area on one side of the insertion element includes at least one (flange) coolant outlet. Each (flange) coolant outlet can include a recess that, viewed along a radial direction of the pin, widens outwards in a circumferential direction and / or narrows outwards in a longitudinal direction. The at least one (flange) coolant outlet is designed to allow coolant to pass between the tool and the flange on the side of the tool facing away from the machine (on the side facing the flange area), even when the tool is in contact with the flange's contact surface. This allows the side of the tool facing away from the machine to be cooled with coolant. In other words, the at least one (flange)

[0075] August 29, 2025 N 30 P 9

[0076] The coolant outlet forms a local interruption of the contact surface for the tool to allow coolant to pass through.

[0077] In one embodiment, the basic shape of the lateral surface can be formed in a rotating manner around the longitudinal axis of the insertion element. In other words, as the position along the longitudinal axis of the insertion element progresses, the basic shape of the lateral surface rotates increasingly further around this longitudinal axis, particularly concentrically. For example, (outer) edges of the lateral surface, which are formed by the tips of the basic shape (optionally rounded), can extend helically around the longitudinal axis (of the insertion element). The lateral surface of the insertion element can thus be spirally formed along the longitudinal axis.

[0078] According to one aspect, at least one coolant recess can be formed in the outer surface of the insertion element, extending from a machine-side end of the outer surface over at least a portion of the insertion element's length. It can be located in a region of the outer surface with minimal torque transmission during operation. The coolant recess can, for example, be parallel to the longitudinal axis of the insertion element or helically shaped. It can be configured such that it is not blocked when the insertion element is inserted into the inner recess.

[0079] Furthermore, several coolant recesses can be formed in the outer surface. In particular, a number of these coolant recesses can correspond to a number of points on the basic shape of the outer surface of the insertion element (for example, five or six). The coolant recesses can be arranged uniformly along the circumference.

[0080] The basic shape of the insertion element in the cross-section perpendicular to the longitudinal axis (of the insertion element) can in particular be a regular polygon with

[0081] August 29, 2025 N 30 P 9 The features must correspond to at least five rounded corners or a hypocycloid with at least five points. One, several, or all points may be rounded. The advantages described for these features regarding the internal recess apply accordingly.

[0082] The above-mentioned problem is further solved by a tool having the features of claim 20.

[0083] The embodiments and advantages described with regard to the pin apply accordingly to the tool and vice versa.

[0084] The tool is suitable for mounting onto an insertion element of a pin, in particular a pin according to the invention.

[0085] The tool has a continuous opening for inserting the insertion element.

[0086] According to the invention, a) a basic shape of a cross-section of the mounting opening (along a longitudinal axis of the mounting opening and / or a central axis of the tool) corresponds to a polygon with at least five points, a hypocycloid with at least five points, a pericycloid or an epicycloid and / or b) at least one coolant recess for the passage of coolant is additionally formed on a lateral surface of the mounting opening.

[0087] The special basic shapes of the cross-sectional area of ​​the mounting opening described in the preceding paragraph a) allow for the reliable transmission of particularly high torques from the pin, especially the insertion element, to the tool. Furthermore, they allow for reliable and precise

[0088] August 29, 2025 N 30 P 9

[0089] Positioning of the tool on the insertion element. The insertion opening is designed to engage positively with the corresponding insertion element of the pin.

[0090] In general, the basic cross-sectional shape of the tool's mounting opening can also correspond to other shapes, for example, a rectangle, in particular a square, a polygon with three or four points, or a hypocycloid with one or four points. One, several, or all points can be rounded. In addition to the basic shape, the tool also has at least one coolant recess formed in its cylindrical surface. This at least one coolant recess establishes a direct fluid connection (along a longitudinal direction) from one end face of the tool to another, even when the tool is mounted on the insert.Since the basic shape of the cross-section of the tool's mounting opening corresponds to the basic shape of the insertion element (in the cross-section to its longitudinal axis), in this mounted state, without the additional coolant recess at the mounting opening, no (significant) passage of coolant between the outer surface of the insertion element and the tool would be possible.

[0091] The at least one coolant outlet (of the tool) can be located in a region of the cylindrical surface of the mounting opening where the torque transmission (during operation) is lowest. The at least one coolant outlet can be located along a circumferential direction (of the tool) in a central region between two successive peaks of the basic shape of the mounting opening. Little torque could be transmitted in this central region anyway. Therefore, in this region along the circumferential direction, the positive locking between the mounting opening and the cylindrical surface of the insertion element of the pin can be interrupted particularly easily.

[0092] August 29, 2025 N 30 P 9

[0093] The tool can have a disc-shaped base with a central axis. The mounting opening can extend along the central axis.

[0094] According to further training, the total thickness of the tool (along the longitudinal axis of the mounting opening or the central axis of the tool) is less than 5 mm, for example, less than 4 mm, and specifically between 1 mm and 3 mm. The tool is therefore particularly thin. Manufacturing requires little material, which reduces costs. The basic shape of the mounting opening allows for high torque transmission despite the tool's thinness. Of course, the overall thickness of the tool can generally be greater.

[0095] In one embodiment, the basic shape of the mounting opening can be formed to rotate around its longitudinal axis. In other words, as the mounting opening's position increases along its longitudinal axis, the basic shape rotates progressively further around this axis, particularly concentrically. For example, grooves on the outer surface of the mounting opening, formed by the tips of the basic shape (optionally rounded), can run helically around the longitudinal axis. Thus, the outer surface of the mounting opening can be spirally formed along its longitudinal axis.

[0096] The above-mentioned problem is further solved by a tool fastening system for fastening a tool to a machine tool (for example, to a tool connection of a machine tool), comprising a tool holder adapter according to the invention and a (suitable) pin according to the invention.

[0097] August 29, 2025 N 30 P 9

[0098] The embodiments and advantages described with regard to the tool holder adapter and / or the pin apply accordingly to the tool fastening system and vice versa.

[0099] In this advanced training, the tool fastening system is designed to allow a tool with a total thickness of less than 5 mm to be fixed between the tool holder adapter and the pin. Specifically, the total thickness can be less than 4 mm, for example, in the range of 1 mm to 3 mm. This enables the use of particularly thin and therefore cost-effective tools. This feature does not generally preclude the use of tools with a greater total thickness. In general, the overall thickness of the tool can, of course, be greater.

[0100] The length of the internal recess of the tool holder adapter, along its longitudinal axis, can be at least equal to the length of the insertion element along its longitudinal axis. This allows for the proper mounting of tools of any thickness. In a further development, the length of the internal recess is at least 0.5 mm greater than the length of the insertion element.

[0101] Alternatively or additionally, tools of different overall thicknesses and / or shank thicknesses can be fixed between the tool holder adapter and the pin. This increases flexibility. In particular, at least tools whose overall thickness and / or shank thickness falls within a range of

[0102] - 1.0 mm, or even 0.07 mm and

[0103] - 3.0 mm, or even 6 mm. This feature defines a "minimum range" regarding permissible overall thicknesses and does not preclude the possibility of fixing even thicker and / or thinner tools.

[0104] August 29, 2025 N 30 P 9

[0105] For example, the length of the insertion element is at least 5 mm. Alternatively or additionally, the length of the inner recess can be at least 8 mm.

[0106] The internal recess of the tool holder adapter can be configured to coaxially accommodate the insertion element of the pin. The insertion element can be displaceable within the internal recess along its longitudinal axis. When the insertion element is at least partially inserted into the internal recess, the insertion element and the internal recess are mechanically engaged in a rotationally secure manner (preventing rotation of the insertion element around the longitudinal axis of the internal recess). This allows for simple, stepless clamping or the mounting of tools of varying thicknesses.

[0107] A machine-facing end face of the tool may have a recess to accommodate the flange area (at least partially).

[0108] The tool can encompass the pin. The pin can be presented as a separate component, or the tool can already be attached to the pin.

[0109] The tool fastening system may include the clamping screw(s).

[0110] The above-mentioned problem is further solved by a tool fastening system for fastening a tool to a machine tool (for example, to a tool connection of a machine tool), comprising a pin according to the invention and a tool according to the invention.

[0111] August 29, 2025 N 30 P 9

[0112] The embodiments and advantages described with respect to the pin and / or the tool apply accordingly to the tool fastening system and vice versa.

[0113] Of course, a tool system according to the invention can comprise the tool holder adapter according to the invention, the pin according to the invention, and the tool.

[0114] In one embodiment, the pin and the tool are flush on the side facing away from the machine when the tool is fully mounted on the pin. This reduces the risk of collision with a workpiece being machined. In particular, the length (in the longitudinal direction) of the flange area can correspond to the depth (along the longitudinal direction) of the recess for receiving the flange.

[0115] The invention is explained below with reference to exemplary embodiments and the figures. All features described and / or illustrated, individually or in any combination, constitute the subject matter of the invention, even independently of their compilation in the claims or their cross-references.

[0116] They show schematically:

[0117] Fig. 1 shows a side view of a tool fastening system comprising a tool holder adapter according to a first embodiment, a pin according to a first embodiment and a clamping screw, as well as a tool which can be fastened to a machine tool by means of the tool fastening system;

[0118] August 29, 2025 N 30 P 9

[0119] Fig. 2A shows a longitudinal section of the tool holder adapter from Fig. 1 (see section line S2A in Fig. 2D);

[0120] Fig. 2B a perspective view of the tool holder adapter from Fig. 1;

[0121] Fig. 2C shows a cross-sectional view of the tool holder adapter from Fig. 1 along a section line S2C in Fig. 2A;

[0122] Fig. 2D shows a top view of a tool-side end face of the tool holder adapter from Fig. 1;

[0123] Fig. 2E is an enlargement of the section M2E in Fig. 2A with a coolant outlet in a tool-side end face of the tool holder adapter from Fig. 1;

[0124] Fig. 2F shows a sectional view along a section line S2F in Fig. 2D;

[0125] Fig. 3A a perspective view of the cone from Fig. 1;

[0126] Fig. 3B shows a top view of a machine-side end face of the pin from Fig. 1;

[0127] Fig. 3C shows a longitudinal section through the pin from Fig. 1;

[0128] Fig. 4A shows a longitudinal section of the tool fastening system from Fig. 1 with the tool from Fig. 1 attached to it;

[0129] Fig. 4B shows a top view of a tool-side end face of the tool fastening system with the tool from Fig. 4A;

[0130] August 29, 2025 N 30 P 9

[0131] Fig. 5 shows the tool fastening system and the tool from Fig. 1, Fig. 4A and Fig. 4, wherein the tool is attached to a machine connection of a machine tool by means of the tool fastening system;

[0132] Fig. 6A shows a modified embodiment of the pin from Fig. 1 with coolant outlets on a flange area in a side view;

[0133] Fig. 6B shows a top view of a machine-side end face of the pin from Fig. 6A;

[0134] Fig. 6C shows a longitudinal section through the pin from Fig. 6A;

[0135] Fig. 7A shows a longitudinal section of a modification of the tool fastening system from Fig. 1 with the tool from Fig. 1 attached thereto, wherein the tool fastening system comprises the modified pin from Fig. 6A to Fig. 6C instead of the pin from Fig. 1;

[0136] Fig. 7B shows a top view of a tool-side end face of the tool fastening system with the tool from Fig. 7A;

[0137] Fig. 8A shows a perspective view of another embodiment of a tool holder adapter;

[0138] Fig. 8B shows a top view of a tool-side end face of the tool holder adapter from Fig. 8A;

[0139] Fig. 8C shows a side view of the tool holder adapter from Fig. 8A;

[0140] August 29, 2025 N 30 P 9

[0141] Fig. 8D shows a longitudinal section through the tool holder adapter from Fig. 8A along a section line S8D in Fig. 8B;

[0142] Fig. 9A is a perspective view of an embodiment of a pin for the tool holder adapter from Fig. 7A;

[0143] Fig. 9B shows a longitudinal section through the pin from Fig. 9A;

[0144] Fig. 9C shows a top view of a machine-side end face of the pin from Fig. 9A;

[0145] Fig. 10A shows a modified embodiment of the pin from Fig. 8A with coolant outlets on a flange area in a perspective view;

[0146] Fig. 10B shows a longitudinal section through the pin from Fig. 10A;

[0147] Fig. 10C shows a top view of a machine-side end face of the pin from Fig. 10A;

[0148] Fig. 11 shows a tool fastening system comprising the tool holder adapter from Fig. 8A, the pin from Fig. 10A and three clamping screws, wherein a tool is fastened to a machine connection of a machine tool by means of the tool fastening system;

[0149] Fig. 12A shows a top view of an end face facing away from the machine of an embodiment of a tool;

[0150] Fig. 12B shows a longitudinal section through the tool from Fig. 12A;

[0151] August 29, 2025 N 30 P 9

[0152] Fig. 13 shows an enlargement of the section M13 in Fig. 7A;

[0153] Fig. 14 shows the tool fastening system used in Fig. 11 in a longitudinal section;

[0154] Fig. 15A shows a perspective view of an insertion element of a pin, in which a basic shape of a lateral surface of the insertion element is formed rotating along a longitudinal axis of the insertion element about this longitudinal axis;

[0155] Fig. 15B shows a side view of the insertion element from Fig. 15A;

[0156] Fig. 15C shows a cross-section of the insertion element at the cut surface S15C in Fig. 15B;

[0157] Fig. 15D shows a cross-section of the insertion element at the cut surface S15D in Fig. 15B;

[0158] Fig. 16A shows a side view of another embodiment of a pin with coolant recesses in the outer surface of the insertion element;

[0159] Fig. 16B shows a perspective view of the tenon from Fig. 16A; and

[0160] Fig. 16C shows a top view of a machine-side end face of the pin from Fig. 16A.

[0161] Fig. 1 shows a side view of a tool 80 and tool fastening system for fastening the tool 80 to a machine tool in

[0162] August 29, 2025 N 30 P 9 in a disassembled state. The tool fastening system comprises a tool holder adapter 10, a pin 50, and a clamping screw 75.

[0163] The tool 80 has a disc-shaped base (see Figs. 1 and 4B). It has a mounting opening 83 in the center. The mounting opening 83 is more clearly visible in Figs. 12A and 12B, which show a similar embodiment of a tool 180.

[0164] On its radial outer region (outside along a radial direction R80), the tool 80 has a plurality of machining features 88. In this example, the machining features 88 are evenly distributed in the outer region along a circumferential direction C80 of the tool 80.

[0165] Tool 80 can be, for example, a circular saw blade, a disc cutter, or a circular knife.

[0166] The embodiment of tool 180 shown in Figs. 11, 12A and 12B differs from tool 80 in Figs. 1, 4A, 4B, 5, 7A and 7B by a different type and a larger number of machining elements 188. Furthermore, the diameter of tool 180 is larger than that of tool 80. Finally, tool 180 is thinner than tool 80 in a radially outer region. Otherwise, tools 80 and 180 are of the same construction.

[0167] The tool holder adapter 10 is shown in more detail in Figures 2A to 2F. A reference to Figure 2 can be used to refer to all individual Figures 2A to 2F.

[0168] August 29, 2025 N 30 P 9

[0169] The pin 50 from Fig. 1 is shown in more detail in Figs. 3A to 3C. A reference to Fig. 3 can be made to the entirety of the individual Figs. 3A to 3C.

[0170] In Figures 1, 2A, 2B, 2E, 2F, 3A, 3C, 4A, 6A, 6C, 7A, 8C, 8D, 9B, 10B, 13, 14, and 16, one side of the machine (a side of the machine tool, not shown) is at the top, and one side of the tool, or the side facing away from the machine, is at the bottom. In Figure 12B, the machine side is on the left and the side facing away from the machine is on the right.

[0171] In Fig. 1, a longitudinal axis LA30 of an inner recess 30 of the tool holder adapter 10, a longitudinal axis LA80 of the mounting opening 83 of the tool 80 and a longitudinal axis LA50 of an insertion element 51 of the pin 50 are arranged along a common longitudinal axis LA.

[0172] Starting from the situation shown in Fig. 1, the tool 80 can be mounted onto the pin 50. For this purpose, the insertion element 51 of the pin 50 is inserted into the mounting opening 83 of the tool 80. The insertion element 51 is inserted along its longitudinal axis LA50 through the mounting opening 83 until an end face 82 of the tool 80 facing away from the machine rests against a machine-side contact surface 61 of a flange area 60 of the pin 50.

[0173] Then the free, machine-side end of the insertion element 51 is inserted into the inner recess 30 of the tool holder adapter 10 until a machine-side end face 81 of the tool 80 rests against an end contact surface 21 of a neck structure 20 of the tool holder adapter 10.

[0174] Finally, the pin 50 is secured to the tool holder adapter 10 by means of the clamping screw 75. This secures the tool 80 along the

[0175] August 29, 2025 N 30 P 9 The common longitudinal axis LA between the end face 21 of the tool holder adapter 10 and the contact surface 61 of the pin 50 is secured and axially clamped.

[0176] A basic shape of a cylindrical surface 31 of the inner recess 30 in a cross-section perpendicular to the longitudinal axis LA30 and a basic shape of a cylindrical surface 52 of the insertion element 51 in a cross-section perpendicular to the longitudinal axis LA50 are coordinated with each other. They are designed such that the insertion element 51 can be inserted into the inner recess 30 and is held in the inner recess 30 in a rotationally secure manner (against rotation about the longitudinal axis LA30) due to a positive locking of the two cylindrical surfaces 31, 52. This enables the transmission of torque from the tool holder adapter 10 to the pin 50 during material processing.

[0177] Furthermore, the basic shape of a cylindrical surface 84 of the mounting opening 83 in a cross-section perpendicular to the longitudinal axis LA80 and the basic shape of the cylindrical surface 52 of the insertion element 51 in a cross-section perpendicular to the longitudinal axis LA50 are aligned with each other. They are designed such that the insertion element 51 can be inserted into the mounting opening 83 and is held in a rotationally secure position (against rotation about the longitudinal axis LA50) on the insertion element 51 due to a positive locking of the two cylindrical surfaces 52, 84. This enables the transmission of torque from the pin 50 to the tool 80 during material processing. Finally, the tool 80 can be driven rotaryally by the machine tool via the tool holder adapter 10 and the pin 50.

[0178] The tool holder adapter 10 shown in more detail in Fig. 2 (i.e. in Figs. 2A to 2F) is an elongated component and extends along a longitudinal direction L10, more precisely along its longitudinal axis, from a machine side MS10 to a tool side WS10.

[0179] August 29, 2025 N 30 P 9

[0180] In Fig. 2 it is clearly visible that the longitudinal axis of the entire tool holder adapter 10 coincides with the longitudinal axis LA30 of the inner recess 30 in the neck structure 20. Therefore, no additional reference numeral is necessary for the longitudinal axis of the entire tool holder adapter 10.

[0181] The tool holder adapter 10 comprises an adapter structure 11 and the neck section 20. The adapter structure 11 faces the machine side MS10 of the tool holder adapter 10. The neck structure 20 is formed on the tool side WS10 opposite the longitudinal direction L10. The neck structure 20 can have a cylindrical outer surface 25. Alternatively or additionally, the shank can have a cylindrical (lateral) outer surface 15. The diameters of the surfaces 15 and 25 can be the same or different.

[0182] The adapter structure 11 can be attached to the machine tool. In particular, it can be formed integrally with the machine tool.

[0183] In the illustrated embodiment, the adapter structure 11 is designed for the detachable or reversible fastening of the tool holder adapter 10 to a tool connection 300 of the machine tool (see Fig. 5).

[0184] The tool connection 300 can correspond to a standardized type. Accordingly, the adapter structure 11 can correspond to the standardized type.

[0185] In this example, the tool connection 300 includes a chuck and the adapter structure 11 has a shank 16 for fastening in the chuck.

[0186] August 29, 2025 N 30 P 9

[0187] The shank 16 extends from the neck structure 20 on the machine side parallel to the longitudinal direction L10. It includes a central internal bore 13. Coolant can flow through the internal bore 13 from the machine side MS10, in particular from a machine-side end face 12 of the shank 16 (or the adapter structure 11 and the entire tool holder adapter 10) towards the neck structure 20.

[0188] A rounding and / or chamfer 14 can be formed on an edge region of the inner bore 13 on the machine-side end face 12. Alternatively or additionally, a rounding and / or chamfer 17 can be formed on an outer edge region of the machine-side end face 12. This facilitates the secure insertion of the shank 16 into the tool connection 300.

[0189] The neck structure 20 has an internal recess 30 for inserting the pin 50, more precisely for inserting the insertion element 51. The internal recess 30 extends along the longitudinal axis LA30, which is parallel to the longitudinal direction L10, away from the tool side WS10 and thus away from the end face 21. According to one aspect, the length of the internal recess 30 along the longitudinal axis LA30 corresponds to at least the length of the insertion element 51 (along the longitudinal axis LA50) minus the receiving thickness dA of the tool 80. The receiving thickness dA of the tool 80 corresponds to a reduction of the free length of the insertion element 51 when the tool 80 is mounted on the insertion element 51 and rests against the flange area 60. The receiving thickness dA is shown in Fig. 12B. In particular, the length of the inner recess 30 can be longer than the length of the insertion element 51 .

[0190] Perpendicular to the longitudinal axis LA30, the inner recess 30 has a receiving cross-section (for receiving the insert element 51) with a special basic shape. The basic shape can generally be described as a polygon with

[0191] August 29, 2025 N 30 P 9 at least five cusps 32, a hypocycloid with at least 5 cusps 32, a pericycloid or an epicycloid.

[0192] In other words, the lateral surface 31 of the inner recess 30 has this basic shape in cross-section perpendicular to the longitudinal axis LA30. The lateral surface 31 is the radially inner wall surface of the neck structure 20, which bounds the inner recess 30 in the radial direction R30, i.e., encloses it along the circumferential direction C30.

[0193] In the embodiment shown here, the basic shape corresponds to an elongated hypocycloid with five vertices 32, wherein the vertices 32 are rounded. The diameter of an imaginary circle that just encloses the hypocycloid can, for example, be in a range of 3 mm to 28 mm.

[0194] Optionally, the tool-side edge of the inner recess 30 is rounded and / or chamfered 22. This facilitates the insertion of the plug-in element 52.

[0195] The tool holder adapter 10 also has engagement means that serve to fasten the pin 50 to the tool holder adapter 10. In particular, these serve to secure the pin 50 against the insertion element 51 slipping out of the inner recess 30 (along the longitudinal axis LA30).

[0196] In the embodiment shown in Fig. 2, the engagement means comprise exactly one threaded bore 26 with an internal thread 27. The internal thread 27 can be self-locking.

[0197] The threaded bore 26 adjoins the inner recess 30 directly on the machine side along the longitudinal direction L10. It is located between the

[0198] August 29, 2025 N 30 P 9

[0199] The inner recess 30 and the inner bore 13 are arranged. One longitudinal axis of the inner bore is parallel to the longitudinal axis LA30 of the inner recess 30. Figures 2A and 2D clearly show that the longitudinal axis of the threaded bore 26 lies on a line with the longitudinal axis LA30.

[0200] A screw thread 76 of the clamping screw 75 (see Fig. 1) can be screwed into the threaded bore 26. To allow the coolant to still reach the inner recess 30 or coolant recesses 23 on the inner recess 30 from the inner bore 13 on the machine side MS10, a fluid connection is formed between the inner bore 13 and the coolant recesses 23 (or at least the inner recess 30), which cannot be blocked by the clamping screw 75. This fluid connection can, for example, have at least one coolant channel 24. In the embodiment shown, the inner recess 30 is in fluid contact with the inner bore 13 via several coolant channels 24. Consequently, the tool holder adapter 10 has an integrated passage for coolant from the machine side MS10 into the inner recess 30 by means of the inner bore 13 and the coolant channels 24.The coolant channels 24 can, for example, be formed by bores parallel to the longitudinal direction L10. The bores can be made from the inner recess 30.

[0201] If the length of the inner recess 30 is slightly longer than the length of the insertion element 51, then a free space remains at the machine-side end of the inner recess 30 even when the insertion element 51 is inserted into the inner recess 30 as far as possible without a tool 80 attached or with a tool of minimal thickness attached. The coolant recesses 23 and the coolant channels 24 therefore always remain in fluid contact via the inner recess 30. For this reason, the individual coolant channels 24 can be arranged offset from the individual coolant recesses 23 along the circumferential direction C30 (see Fig. 2D). This

[0202] August 29, 2025 N 30 P 9 Larger areas in a machine-side end surface of the inner recess 30 (at the tips 32 of the basic shape of the receiving cross-section) can be used for the introduction of the coolant channels 24. Furthermore, a separate coolant channel 24 does not need to be provided for each coolant recess 23 (see Fig. 8B).

[0203] In the outer surface 31 of the inner recess 30, at least one coolant recess 23 is additionally provided. The coolant recess 23 can extend parallel to the longitudinal axis LA30 over a length of the outer surface 31. It can be configured as a groove in the outer surface 31. For example, it is formed by a bore parallel to the longitudinal axis LA30, the bore partially overlapping an interior space of the basic shape of the receiving cross-section. In the present embodiment, there are several coolant recesses 23; more precisely, a number of coolant recesses 23 corresponds to a number of points 32.

[0204] The respective coolant recess 23 is arranged in the outer surface 31 between two adjacent points 32 (along the circumferential direction C30). In this area, due to the adapted basic shapes of the outer surfaces of the inner recess 30 and the insertion element 51, the least torque is transmitted during operation, even without the coolant recesses 23. Therefore, the basic shape of the outer surface 31 of the inner recess 30 can be particularly advantageously "interrupted" here by the additional coolant recesses 23.

[0205] Coolant outlets 40 are also provided on the tool-side end contact surface 21 of the tool holder adapter 10.

[0206] In the following, one of these coolant outlets 40 will be described in more detail. The coolant outlet 40 opens at its radially inner region into a

[0207] August 29, 2025 N 30 P 9 The coolant outlet 40 is formed by a recess in the tool-side end face 21. Along the circumferential direction C30, it is bounded by two side walls 41. Radially outwards (i.e., with increasing distance along the radial direction R30 from the central axis or longitudinal axis LA30), the width 42 of the coolant outlet 40 increases in the circumferential direction C30, for example, continuously. This is clearly visible in Fig. 4.

[0208] Alternatively or additionally, the coolant outlet 40 can decrease in size radially outwards in the longitudinal direction L10. This is particularly well illustrated in Fig. 2E, which shows an enlarged section M2E in Fig. 2A. In this case, a "bottom surface" of the coolant channel can be inclined at least substantially by an angle α relative to a plane perpendicular to the longitudinal direction L10. The angle α can, for example, be in a range from 0.5° to 10°.

[0209] The length of the coolant outlet 40 along the longitudinal direction can, for example, have values ​​in the range of 0.1 mm to 1 mm.

[0210] The coolant outlet 40 can be formed, for example, by driving a cylindrical milling head with an inclination to the longitudinal direction L10 and with partial overlap into the tool-side end contact surface 21, where the inclination corresponds to the angle a.

[0211] Another possibility is to drive a cylindrical milling head, which has a conical recess at a free end, parallel to the longitudinal direction 10 and with partial overlap into the end face 21. A central axis of the milling head at the free end is preferably located outside a radially outer end of the end face 21. The cone angle of the conical recess of the milling head is, for example, (90° - a) / 2. In this case, the bottom surface 43 of the

[0212] August 29, 2025 N 30 P 9

[0213] The coolant outlet is curved at 40° and the angle α varies locally. This is most easily understood with reference to Fig. 2F.

[0214] The tool-side end contact surface 21 is otherwise flat and serves to contact the machine-side end face 81 of the tool 80.

[0215] Figures 3A to 3C show different representations of the pin 50 from Figure 1. A reference to Figure 3 can be made to the entirety of Figures 3A to 3C.

[0216] The journal 50 extends parallel to a longitudinal direction L50 (of the journal 50) from its machine side MS50 to its side facing away from the machine, which is also referred to as the tool side WS50. The journal 50 comprises the insertion element 51 on the machine side MS50 and the flange area 60 on the tool side WS50. The longitudinal axis LA50 of the insertion element 51 simultaneously forms a longitudinal axis of the entire journal 50. In other words, the continued longitudinal axis LA50 of the insertion element 51 can also be considered the longitudinal axis of the flange area 60 in this case.

[0217] The insertion element 51 serves, as described above, for positive-locking insertion into the inner recess 30 of the tool holder adapter 10.

[0218] The basic shape of the lateral surface 52 in the cross-section transverse to the longitudinal axis LA50 generally corresponds to a polygon with at least five vertices 53, or a hypocycloid with at least five vertices 53, a pericycloid or an epicycloid.

[0219] In the embodiment shown here, the basic shape corresponds to an elongated hypocycloid with five tips 53, wherein the tips 53 are rounded.

[0220] August 29, 2025 N 30 P 9

[0221] The diameter of an imaginary circle that just encloses the hypocycloid can, for example, range from 3 mm to 28 mm.

[0222] As already mentioned, the basic cross-sectional shape of the outer surface 52 of the insertion element 51 and the basic cross-sectional shape of the receiving cross-section of the inner recess 30 are identical, and their dimensions are coordinated. Thus, the insertion of the insertion element 51 and a suitable positive fit between the outer surface 52 of the insertion element 51 and the outer surface 31 of the inner recess 30 are ensured.

[0223] A machine-side end face 56 of the insertion element 51 can be rounded and / or have a chamfer 54. This facilitates insertion into the inner recess 30 of the tool holder adapter 10.

[0224] The flange area 60 is arranged at the opposite end of the insertion element 51 along the longitudinal direction L50. Towards the machine side MS50, the contact surface 61 for the tool 80 is formed on the flange area 60. When the insertion element 51 is fully inserted into the mounting opening 83 of the tool 80, a radially inner area of ​​the machine-away end face 82 of the tool 80 rests directly against the contact surface 61.

[0225] A circumferential groove 59 can be formed at a transition between the insertion element 51 and the flange area 60. The groove 59 serves as a relief groove. The circumferential groove 59 can be formed in the outer surface 52 and / or in the contact surface 61.

[0226] The pin 50 has at least one countersunk bore 55 that extends completely through the pin 50 along the longitudinal direction L50. The pin 50 is shown in Fig. 1.

[0227] August 29, 2025 N 30 P 9 and 3 has exactly one countersunk bore 55, which is formed coaxially with the longitudinal axis LA55.

[0228] Figure 3C shows that a first section 55B of the countersink 55, with a larger diameter, opens towards the side facing away from the machine (bottom of Figure 3C), while a second section 55D, with a smaller diameter, opens towards the machine side MS50. A transition section 55C of the countersink 55 is arranged between these two sections. In the example shown, the transition section 55C has a frustoconical shape. However, the transition section 55C could also have one or more steps.

[0229] The transition area 55C serves as a bearing surface for the screw head 77 of the clamping screw 75. When the insertion element 51 is pushed through the mounting opening 83 of the tool 80 as far as possible and further inserted into the inner recess 30 of the tool holder adapter 10, the clamping screw 75 is inserted into the countersunk bore 55 and its screw thread 76 is screwed into the threaded bore 26. The screw head 77 comes to rest against the transition area 55C. By further tightening the clamping screw 75, the tool 80 is increasingly clamped between the pin 50 (more precisely, the bearing surface 61) and the neck structure 20 (more precisely, the end bearing surface 21). The continuous tapering of the transition area 55C towards the machine side MS50 and the adapted shape of the screw head 77 contribute to self-centering.

[0230] The opening of the countersunk bore 55 on the side facing away from the machine can be rounded and / or have a chamfer 55A. This facilitates the insertion of the clamping screw 75. Alternatively or additionally, the opening of the countersunk bore 55 on the machine side 50 can be rounded and / or have a chamfer 55E.

[0231] August 29, 2025 N 30 P 9

[0232] Figures 4A and 4B show the components shown in Figure 1 in an assembled state. The tool 80 is placed on the insertion element 51, the insertion element 51 is inserted into the inner recess 30, and the pin 50 is secured and tightened to the threaded bore 76 by means of the clamping screw 75.

[0233] The tool 80 includes a recess 87. The recess 87 can at least partially accommodate the flange area 60.

[0234] In this embodiment, the flange area 60 is relatively short along the longitudinal direction 50. Therefore, in the assembled state shown in Fig. 4A, the flange area 60 is completely enclosed within the recess 87 of the tool 80. The end face 62 of the flange area 60 facing away from the machine and a region of the end face 82 of the tool 80 facing away from the machine, surrounding the recess 87, are flush.

[0235] In Fig. 4A, it is clearly visible that the tool holder adapter 10 and the pin 50 are designed for stepless clamping. This means that tools 80 with any mounting thickness dA can be clamped. This applies at least as long as the mounting thickness dA is within a permissible range. The permissible range can, for example, extend from at least 1.2 mm to 6.0 mm. In Fig. 12B, the mounting thickness dA is the total thickness dL minus the depth of the recess 87.

[0236] In Fig. 5, the assembled ensemble from Figs. 4A and 4B is further attached to a tool holder 300 of the machine tool. The tool holder 300 comprises a chuck into which the shank 16 of the adapter structure 11 of the tool holder adapter 10 is clamped.

[0237] August 29, 2025 N 30 P 9

[0238] Figures 6A to 6C show various representations of another embodiment of a pin 150. Its construction, function, and advantages are fundamentally the same as those of the pin 50 shown in Figures 1 and 3. The same reference numerals are used for identical elements. Only the essential differences between the pin 150 and the pin 50 are described below.

[0239] A reference to Fig. 6 can refer to the entirety of the individual Figs. 6A to 6C.

[0240] The pin 150 differs from the pin 50 by a modified flange area 160. The flange area 160 has several coolant outlets 165 on one side of the insertion element 51.

[0241] Each coolant outlet 165 includes a recess. Radially outward (i.e., with increasing distance along a radial direction R50 from the central axis or longitudinal axis LA50), the recess widens in a circumferential direction C50 of the pin 150. Accordingly, in Fig. 6B, a distance (along the circumferential direction C50) between the side walls 166 of the coolant outlet 165 widens. Alternatively or additionally, the width of the recess 87 can decrease radially outward along the longitudinal direction L50. In Fig. 6C, the bottom 167 of the coolant outlet 165 is slightly inclined (cf. angle a in Fig. 2E).

[0242] The various methods for manufacturing the coolant outlets 40 in the tool holder adapter 10 can be used analogously for manufacturing the coolant outlets 165.

[0243] Figures 7A and 7B are essentially the same as Figures 4A and 4B. The difference lies in the use of pin 150 instead of pin 50. As shown in

[0244] August 29, 2025 N 30 P 9

[0245] In Fig. 4A, the coolant can reach the inner recess 30 from the machine side MS10 through the inner bore 13 and the coolant channels 24. It then flows through the coolant recesses 23 past the insertion element 51 to the coolant recesses 40. Some of the coolant exits the coolant recesses 40. Another portion of the coolant is guided through coolant recesses 86 of the tool 80 (see also Figs. 12A and 12B) past the insertion element 51 to the side 82 of the tool 80 facing away from the machine, where it enters the coolant outlets 165. The positions of the coolant recesses 23 and 86, as well as the coolant outlets 40 and 165, are aligned accordingly.

[0246] Fig. 13 shows the section M13 in Fig. 7A enlarged. Here, the coolant outlets 40 and 165 on the two opposite end faces 81 and 82 of the tool 80 are particularly easy to see.

[0247] Figures 8A to 8C show various representations of another embodiment of a tool holder adapter 110. Its construction, function, and advantages are fundamentally the same as those of the tool holder adapter 10 shown in Figures 1 and 4. The same reference numerals are used for identical elements. Only the essential differences between the tool holder adapter 110 and the tool holder adapter 10 are described below.

[0248] A reference to Fig. 8 can refer to the entirety of the individual Figs. 8A to 8C.

[0249] Compared to the tool holder adapter 10 from Fig. 2, the inner recess 30 of the tool holder adapter 110 is larger transverse to the longitudinal axis LA30, i.e. in the radial direction R30.

[0250] August 29, 2025 N 30 P 9

[0251] In the tool holder adapter 110 shown in Fig. 8, the basic shape of the receiving cross-section (or the cylindrical surface 31 in cross-section perpendicular to the longitudinal axis LA30) corresponds to an elongated hypocycloid with six points 32, the points 32 being rounded. The diameter of an imaginary circle that just encloses the hypocycloid can, for example, be in a range of 9 mm to 50 mm. Due to the larger diameter of the enclosing circle, this embodiment enables the greatest possible torque transmission with six points 32 instead of five.

[0252] The embodiment of the tool holder adapter 110 shown in Fig. 8 has three threaded bores 26, each with an internal thread 27, as engagement means. All threaded bores 26 adjoin the inner recess 30 directly on the machine side along the longitudinal direction L10. They are arranged at equal radial intervals to the longitudinal axis LA30. Furthermore, they are arranged uniformly (i.e., uniformly offset from one another) along the circumferential direction C30. This facilitates uniform tightening of the pin 150 (or the pin 250) by means of three threaded screws 75.

[0253] Furthermore, an adapter structure 111 of the tool holder adapter 110 has several transverse grooves 116 on the machine-side end face 16. The transverse grooves 116 each extend along the radial direction R30 and are evenly spaced along the circumferential direction C30. The illustrated embodiment has two transverse grooves 116, of which only one is visible at any given time due to perspective. In general, no transverse groove 116, one transverse groove 116, or at least three transverse grooves 116 can also be formed. Alternatively, the shank 16 can also be formed integrally with the machine tool.

[0254] Inside the tool holder adapter 110, the coolant channels 24, which extend along the longitudinal direction L10, are located radially so far outwards that they overlap only slightly or not at all with the inner bore 13. Therefore, a

[0255] August 29, 2025 N 30 P 9 An additional fluid connection 124 is created in the radial direction, for example by a groove in a cylindrical surface of the inner bore 13 and / or by radially extending connection channels at a tool-side end of the inner bore 13.

[0256] Figures 9A to 9C show various representations of another embodiment of a pin 250. Its construction, function, and advantages are fundamentally the same as those of the pin 50 shown in Figures 1 and 3. The same reference numerals are used for identical elements. Only the essential differences between the pin 250 and the pin 50 are described below.

[0257] A reference to Fig. 9 can refer to the entirety of the individual Figs. 9A to 9C.

[0258] The pin 250 is adapted to the tool holder adapter 110. In particular, the basic shape of its cylindrical surface 51 in cross-section perpendicular to the longitudinal axis LA50 and the size of the insertion element 51 are adapted to the inner recess 30 of the tool holder adapter 110.

[0259] Therefore, the basic shape of the lateral surface 51 in cross-section perpendicular to the longitudinal axis LA50 corresponds to an elongated hypocycloid with six vertices 53, where the vertices 53 are rounded. The diameter of an imaginary circle that directly encloses the hypocycloid can, for example, lie in a range of 9 mm to 50 mm.

[0260] In addition, the pin 250 has three countersunk holes 55 instead of one countersunk hole 55. Furthermore, it has an additional blind hole 257 on the side facing away from the machine, which serves to facilitate handling.

[0261] August 29, 2025 N 30 P 9

[0262] Figures 10A to 10C show various representations of another embodiment of a pin 350. Its construction, function, and advantages are fundamentally the same as those of the previously described pins 50, 150, and 250. The same reference numerals are used for identical elements.

[0263] A reference to Fig. 9 can refer to the entirety of the individual Figs. 9A to 9C.

[0264] In principle, the pin 350 in Fig. 10 corresponds in particular to the pin 250 in Fig. 9. Specifically, their insertion elements 51 are identical. The pin 350 also fits the tool holder adapter 110 from Fig. 8. However, compared to the pin 250, the pin 350 has the longer flange area 160 with the additional coolant outlets 165. The explanations regarding the differences between the pin 150 from Fig. 6 and the pin 50 from Figs. 1 and 3 apply analogously to the differences between the pin 350 from Fig. 10 and the pin 250 from Fig. 9.

[0265] The tool holder adapter 110 and the matching pins 250 and 350 are designed to accommodate a larger tool 280 from Fig. 11.

[0266] Figure 11 shows a tool fastening system with the tool holder adapter 110 from Figure 8 and the pin 350 from Figure 10. The tool fastening system optionally includes a tool 280. The components of the tool fastening system are assembled and attached to a tool port 400 of the machine tool. The tool 280 can have the same features as the tool 180 in Figures 12A and 12B, but its mounting opening 83 is adapted to the pins 250 and 350.

[0267] In the tool adapter 110, an additional countersunk bore 28 is formed between the inner recess 30 and the inner bore 13 (see Figs. 8B and 8B).

[0268] August 29, 2025 N 30 P 9

[0269] 8D). The countersunk bore 28 thus connects the inner recess 30 with the inner bore 13. It has a first section 28A of larger diameter, which opens into the inner recess 30. It also has a second section 28C of smaller diameter, which opens into the inner bore 13. Between these sections, it has a transition section 28B. The tool connection 400 (see Fig. 11) can have a boss (not shown) that can be received by the inner bore 13. To secure the tool holder adapter 110 to the tool connection 400, a locking screw 178 can be inserted through the inner recess 30 and screwed into the boss. The transition section 28B then serves as a bearing surface for the screw head 179 of the locking screw 178. The locking screw 178 can be hollow to allow coolant flow. In the tool holder adapter 110, the countersunk bore 28 extends coaxially to the longitudinal axis LA30.

[0270] Figures 12A and 12B show the details of the tool 180 particularly well. The tool 180 is essentially disc-shaped with a small thickness. For example, the total thickness dL along the longitudinal axis LA80 can be less than 6 mm. The continuous mounting opening 83 extends along the longitudinal axis LA80 between the machine-side end face 81 and the machine-away end face 82. The size and basic shape of the mounting opening 83 in cross-section perpendicular to the longitudinal direction LA80 are adapted to the insertion element 51, as formed in the pin 50 and the pin 150. Permissible coolant openings 86 are provided in areas of the cylindrical surface 84 where, during operation, the least torque can be applied by means of the insertion element 51 for rotation about the longitudinal axis LA80.In each central region along the circumferential direction C80 between adjacent peaks 85 of the cylindrical surface 84, one of the coolant recesses 86 is arranged, extending parallel to the longitudinal axis LA80 between the machine-side end face 81 and the machine-away end face 82. On the machine-away end face 82.

[0271] August 29, 2025 N 30 P 9 The receptacle 87 is formed around the mounting opening 83 and the coolant recesses 86 to receive the flange area 60 or to partially receive the flange area 160. The coolant recesses 86 are optional.

[0272] Tools 80, 180, and 280, for example, can be made of carbide, high-speed steel (HSS), and / or high-speed steel with increased cobalt content (HSS-E). This ensures a long tool life.

[0273] The flange area 60 of the pin 50 in Fig. 2 (and analogously of the pin 250 in Fig. 9) has a very short length along the longitudinal direction L50, for example, less than 1.0 mm, in particular less than 0.8 mm. Accordingly, the recess 87 can have a very shallow depth (along the longitudinal direction), for example, less than 1.0 mm, in particular less than 0.8 mm, and still completely accommodate the flange area 60. Machining the material of the tool 80, 180, 280, e.g., carbide, is very complex and expensive. The smaller the recess 87, the more cost-effectively the tool 80, 180, 280 can be manufactured.

[0274] The insert element 51 can have a clearance fit with respect to the mounting opening 83. This facilitates the insertion and removal of the tool 80, 180, 280. Alternatively, the insert element 51 can have an interference or transition fit with respect to the mounting opening 83. In this case, the tool 80, 180, 280 can be pressed onto the insert element 51 at the factory. The tool 80, 180, 280 and the pin 50, 150, 250, 350 then form a single unit.

[0275] Alternatively or additionally (to the coolant recesses 23 and / or 86), at least one coolant recess 58 can be formed in the outer surface 52 of the insertion element 51. It can extend along the longitudinal direction L50.

[0276] August 29, 2025 N 30 P 9 The coolant recesses extend and can, for example, be designed as a groove in the cylindrical surface 52. They can be located in a region (or regions) of the cylindrical surface 52 with the lowest torque transmission during operation, for example, centrally between adjacent centers 53. In particular, several coolant recesses can be arranged in the cylindrical surface 52. The cross-sectional area of ​​the coolant recess can remain constant or vary along the longitudinal direction L50. For example, it can become smaller, at least in certain areas, towards the tool side WS50. This makes it easier to allow a minimum proportion of the coolant to exit through the coolant outlets 40.

[0277] Optionally, the receiving cross-section, the basic shape of the receiving cross-section of the inner recess, the basic shape of the lateral surface of the insertion element and / or the basic shape of the mounting opening can be designed to rotate along the (respective longitudinal axis).

[0278] This is explained using Figures 15A to 15D, which show a modified insertion element 51. Figure 15A shows a perspective view of this insertion element 51, Figure 15B shows a side view, Figure 15C shows a first cross-section transverse to the longitudinal axis LA50 in Figure 15B at a point xL1 along the longitudinal axis LA50, and Figure 15D shows a second cross-section transverse to the longitudinal axis LA50 in Figure 15B at a point xL2 along the longitudinal axis LA50.

[0279] As the position along the longitudinal axis LA50 progresses, the basic shape of the lateral surface 52 rotates increasingly concentrically around the longitudinal axis LA50. A rotation angle θ(xL) of the basic shape at an axial position xL along the longitudinal axis LA50 can, for example, be given by θ(xL) = cL*xL, where cL is a constant. Accordingly, at the axial position xL1 in Fig. 15B, the rotation angle θ(xL1) of the basic shape shown in Fig. 15C is present, while at the axial position xL2 in Fig. 15B, the angle shown in Fig. 15D is present.

[0280] August 29, 2025 N 30 P 9 The rotation angle θ(xL2) shown is of the basic form. θ(xL2) is greater than θ(xL1). Accordingly, the same tip 53 of the basic form, which is highlighted with reference numeral 53' in Fig. 15C, is highlighted with reference numeral 53" in Fig. 15D.

[0281] The surface 52 can be conceptually defined by essentially shifting its basic shape from the machine-side end of the surface 52 along the longitudinal axis LA50 and simultaneously rotating it about the longitudinal axis LA50 according to the aforementioned formula. The individual points or sections of a circumference of the basic shape are each shifted along a helical path around the longitudinal axis LA50.

[0282] In Fig. 15A it is clearly visible how one of the rounded tips 53 of the basic shape of the lateral surface 52 forms an edge 53a of the lateral surface 52. This edge 53a extends along the longitudinal direction L50 and is helical in shape.

[0283] Similarly, the mounting opening 83 of the tool 80, 180, 280 and / or the cylindrical surface 31 of the inner recess 30 can be designed. In a system, the directions of rotation and pitches of the helical profiles preferably match.

[0284] An embodiment of a pin 450 with several coolant recesses 458 in the outer surface 52 of the insertion element 51 is shown in a side view in Fig. 16A, in a perspective view in Fig. 16B, and in a top view in Fig. 16C. The pin 450 otherwise corresponds to the pin 150.

[0285] The coolant recesses 458 extend from the machine-side end of the shell surface 52 at least over the length of the insertion element 51.

[0286] August 29, 2025 N 30 P 9

[0287] The coolant recesses 458 are grooves and extend parallel to the longitudinal axis LA50 of the insertion element 51. They are configured such that they are not blocked when the insertion element 51 is inserted into the inner recess 30.

[0288] Along the circumferential direction C50, a coolant recess 458 is arranged between adjacent peaks 32 of the basic shape of the cylindrical surface 52, more precisely along the circumferential direction C50 in a central region between adjacent peaks 32. These are the regions of the cylindrical surface 52 with the lowest torque transmission during operation. The coolant recesses 458 are arranged uniformly along the circumferential direction C50. One number of coolant recesses 458 corresponds to one number of peaks 32.

[0289] For each of the coolant outlets 165, a coolant recess 458 is provided.

[0290] The coolant recesses 458 each extend at least over the entire length of the shell surface 52.

[0291] In the embodiment shown, the coolant recesses 458 extend further along the longitudinal direction L50, for example towards the end face 62 facing away from the machine, beyond the contact surface 61. Even if a tool similar to the tool 80 or 180 is mounted without coolant recesses 86, a fluid connection is maintained between the coolant recess 458 in the area of ​​the outer surface 52 of the insertion element 51 and the associated coolant outlet 165.

[0292] The respective coolant recess 458, more precisely a machine-away end 459 of the coolant recess, can lead directly into the associated coolant outlet 165. The machine-away end 459 can

[0293] August 29, 2025 N 30 P 9 form part of the associated coolant outlet 165. Of course, the coolant recesses 458 extending away from the machine beyond the cylindrical surface 52 (cf. the machine-away ends 459) and the coolant recesses 86 in the tool 80, 180 do not generally exclude each other.

[0294] The machine-side ends of the coolant recesses 458 can be formed on the machine-side end face 56 and / or on the chamfer 54. In the embodiment shown, they are formed on the chamfer 54.

[0295] On the machine side, the coolant outlets 458 open towards the machine-side end of the inner recess 30 when the insertion element 51 (similar to Fig. 7A) is inserted into the inner recess. Accordingly, a fluid connection is created for each of the coolant outlets 165 via the associated coolant outlet 458 to the machine-side end of the inner recess 30, even if no coolant outlets 23 are formed in the outer surface 31 of the inner recess 30.

[0296] Naturally, coolant recesses 458 can be formed both in the outer surface 52 of the insertion element 51 and on the outer surface 31 of the inner recess 30.

[0297] August 29, 2025 N 30 P 9

[0298] Reference symbol list:

[0299] 10; 110 Tool holder adapter

[0300] 11, 111 Adapter structure

[0301] 12 (machine-side) end face

[0302] 13 Internal bore

[0303] 14th phase

[0304] 15 outdoor area

[0305] 16 shaft

[0306] 20 Neck structure

[0307] 21 Front contact surface

[0308] 22nd phase

[0309] 23 Coolant recess

[0310] 24 Coolant channel

[0311] 25 lateral surface area

[0312] 26 threaded holes

[0313] 27 internal threads

[0314] 28 Countersink

[0315] 28A first area

[0316] 28B Transition area

[0317] 28C second area

[0318] 30 Internal recess

[0319] 31 Surface area (of the inner recess 30)

[0320] 32 peak

[0321] 40 Coolant outlet

[0322] 41 Side wall

[0323] 42 width

[0324] 43 Floor

[0325] 50; 150; 250; 350 cones

[0326] 51 Insert element

[0327] 52 Surface area

[0328] August 29, 2025 N 30 P 9

[0329] 53 Peak

[0330] 53a Edge

[0331] 54th phase

[0332] 55 Countersink

[0333] 55A, 55E phase

[0334] 55B first area

[0335] 55°C transition range

[0336] 55D second area

[0337] 56 (machine-side) front

[0338] 58 Coolant recess

[0339] 59 Nut

[0340] 60; 160 flange area

[0341] 61 Plant area

[0342] 62 (machine-facing) front

[0343] 75 Tensioning screw

[0344] 76 screw threads

[0345] 77 screw head

[0346] 80; 180; 280 tool

[0347] 81 (machine-side) front

[0348] 82 (machine-facing) front

[0349] 83 Mounting opening

[0350] 84 lateral surface area

[0351] 85 peak

[0352] 86 Coolant recess

[0353] 87 Recess (for flange area 60; 160)

[0354] 88; 188 processing element

[0355] 116 Transverse groove

[0356] 124 Fluid connection

[0357] 165 Coolant outlet

[0358] 166 side wall

[0359] August 29, 2025 N 30 P 9

[0360] 167 Base 178 Securing screw 179 Screw head 257 Blind hole 300; 400 Tool connection C30, C50, C80 Circumferential direction dA Mounting thickness dL Total thickness

[0361] MS10, MS50 Machine side M2E, M13 Cutout S2C, S2A, S2F Cutting line S6C, S8D Cutting line L10, L50 Longitudinal direction

[0362] LA, LA30, LA50, LA80 Longitudinal axis R30, R50, R80 Radial direction WS10, WS50 Tool side (side away from machine) xL1, xL2 Position a Angle θ(xL1), θ(xL2) Angle of rotation

[0363] August 29, 2025 N 30 P 9

Claims

1. Claims:

1. Tool holder adapter (10; 110) for attaching a tool (80; 180; 280) by means of a pin (50; 150; 250; 350; 450) to a machine tool, wherein the tool holder adapter (10; 110) extends along a longitudinal direction (L10) from a machine side (MS10) to a tool side (WS10) and - towards the machine side (MS10) has an adapter structure (11; 111) for attaching the tool holder adapter (10; 110) to a tool connection (300; 400) of the machine tool and / or is attached to the machine tool and - on the tool side (WS10) has a neck structure (20), wherein the neck structure (20) has an inner recess (30) for inserting the pin (50; 150; 250; 350; 450), which extends from the tool side (WS10) along a longitudinal axis (LA30) parallel to the longitudinal direction (L10), and wherein the tool holder adapter (10; 110) has engagement means (26, 27) for attaching the pin (50; 150; 250; 350; 450) to the tool holder adapter (10; 110), characterized in that the inner recess (30) has a receiving cross-section perpendicular to the longitudinal axis (LA30), the basic shape of which is a polygon with at least five vertices (32), a hypocycloid with at least five vertices (32), a pericycloid, or an epicycloid corresponds. August 29, 2025 N 30 P 9 WO 2. Tool holder adapter (10; 110) according to claim 1, wherein the basic shape of the holder cross-section corresponds to a regular polygon with at least five points (32) or an elongated hypocycloid with at least five points (32), wherein the points (32) are rounded.

3. Tool holder adapter (10; 110) according to one of the preceding claims, wherein the engagement means (26, 27) comprise at least one internal thread (27) for a clamping screw (75).

4. Tool holder adapter (10; 110) according to claim 3, wherein the at least one internal thread (27) of the engagement means (26, 27) connects to the internal recess (30) on the machine side along the longitudinal direction (L10).

5. Tool holder adapter (10; 110) according to one of the preceding claims, wherein the neck structure (20) has a cylindrical outer surface (25).

6. Tool holder adapter (10; 110) according to one of the preceding claims, wherein the adapter structure (11; 111) has a shaft (16) and / or at least one transverse groove (116) on a machine-side end face (12).

7. Tool holder adapter (10; 110) according to one of the preceding claims, wherein the tool holder adapter (10; 110) has at least one passage (13, 23, 24; 13, 23, 24, 124) for coolant from the machine side (MS10) into the inner recess (30).

8. Tool holder adapter (10; 110) according to one of the preceding claims, wherein the tool holder adapter (10; 110) has a machine-side internal bore (13) extending along the longitudinal direction (L10) from the August 29, 2025 N 30 P 9 WO machine side (MS10) extends, with the inner bore (13) and the inner recess (30) in fluid communication.

9. Tool holder adapter (10; 110) according to one of the preceding claims, wherein at least one coolant recess (23) is additionally provided in a cylindrical surface (31) of the inner recess (30), which extends along the longitudinal direction (L10) and which is arranged in a region of the cylindrical surface (31) with a minimum torque transmission during operation.

10. Tool holder adapter (10; 110) according to one of the preceding claims, wherein an end face (21 ) of the tool holder adapter (10; 110) is formed planar on the tool side (WS10), wherein at least one coolant outlet (40) for radial discharge of coolant from the inner recess (30) is formed in the tool-side end face (21 ).

11. Tool holder adapter (10; 110) according to claim 10, wherein each coolant outlet (40) comprises a recess in the tool-side end face (21) which, viewed along a radial direction (R30) of the tool holder adapter (10; 110), widens outwards in a circumferential direction (C30) and / or narrows outwards in the longitudinal direction (L10).

12. Tool holder adapter according to one of the preceding claims, wherein the basic shape of the receiving cross-section of the inner recess (30) is formed rotating along the longitudinal axis (LA10) of the inner recess (30) about this longitudinal axis (LA10). August 29, 2025 N 30 P 9 WO 13. Pin (50; 150; 250; 350; 450) for attaching a tool (80; 180; 280) to a tool holder adapter (10; 110) according to one of the preceding claims, wherein the pin (50; 150; 250; 350; 450) has an insertion element (51) which extends along its longitudinal axis (LA50) and has a lateral surface (52) whose basic shape in a cross-section transverse to the longitudinal axis (LA50) corresponds to a polygon with at least five vertices (53), a hypocycloid with at least five vertices (53), a pericycloid or an epicycloid.

14. Pin (50; 150; 250; 350; 450) according to claim 13, wherein the pin (50; 150; 250; 350; 450) has at least one continuous countersunk bore (55) extending parallel to the longitudinal axis (LA50) of the insertion element (51).

15. Pin (50; 150; 250; 350; 450) according to one of claims 13 or 14, wherein the pin (50; 150; 250; 350; 450) has a flange area (60; 160) at one end of its insertion element (51) along the longitudinal axis (LA50).

16. Pin (150; 350; 450) according to claim 15, wherein the flange area (160) on one side of the insertion element (51) comprises at least one coolant outlet (165), each coolant outlet (165) comprising a recess which, viewed along a radial direction of the pin (150; 350; 450), widens outwards in a circumferential direction (C50) of the pin (150; 350; 450) and / or narrows outwards in the longitudinal direction (LA50) of the pin (150; 350; 450).

17. Pin according to one of claims 13 to 16, wherein the basic shape of the lateral surface (52) is formed rotating along the longitudinal axis (LA50) of the insertion element (51) about this longitudinal axis (LA50). August 29, 2025 N 30 P 9 WO 18. Pin (450) according to one of claims 13 to 17, wherein at least one coolant recess (458) is formed in the outer surface (52) of the insertion element (51) which extends from a machine-side end of the outer surface (52) at least over a part of a length of the insertion element (51).

19. Pin (50; 150; 250; 350; 450) according to any one of claims 13 to 18, wherein the basic shape of the insertion element (51) in the cross-section transverse to the longitudinal direction (L50) corresponds to a polygon with at least five points (53) or a hypocycloid with at least five points (53), wherein the points (53) are rounded.

20. Tool (80; 180; 280) for mounting onto a plug-in element (51) of a pin (50; 150; 250; 350; 450), wherein the tool (80; 180; 280) has a continuous mounting opening (83) for inserting the plug-in element (51), characterized in that a basic shape of a cross-section of the mounting opening (83) corresponds to a polygon with at least five points (86) or a hypocycloid with at least five points (86) and / or that at least one coolant recess (87) for the passage of coolant is additionally formed in a lateral surface (85) of the mounting opening (83).

21. Tool according to claim 20, wherein the basic shape of the mounting opening (83) is formed rotating along a longitudinal axis (LA80) of the mounting opening (83) about this longitudinal axis (LA80).

22. Tool fastening system for fastening a tool (80; 180; 280) to a machine tool, comprising a tool holder- August 29, 2025 N 30 P 9 WO Adapter (10; 110) according to one of claims 1 to 12 and a pin (50; 150; 250; 350; 450) according to one of claims 13 to 19. August 29, 2025 N 30 P 9 WO

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