Apparatus, system and method for cooling a tool

Abstract

The invention relates to a device for cooling a tool, comprising a base body, a contact element and at least one inlet into the base body, and an outlet of the base body, the inlet and the outlet being connected to each other by one or more internal channels in the base body, and the device being connectable to the tool such that the contact element is in contact with the tool, and the one or more internal channels are designed to conduct cooling liquid. The one or more internal channels include a contact portion in contact with the contact element, and the contact portion includes a plurality of diversion elements designed to locally increase turbulence and flow of the cooling liquid through the contact portion. The invention also relates to a system comprising the apparatus and the tool, and a cooling method using the system.

Description

[0001] This invention relates to an apparatus for cooling a tool, comprising a base, contact elements, at least one inlet into the base, and an outlet out of the base. The inlet and outlet are connected to each other via one or more internal channels within the base. The apparatus is connectable to a tool to bring the contact elements into contact with the tool. The one or more internal channels are used for the conduction of coolant. Each internal channel includes a contact portion that contacts the contact elements. The contact portion includes a plurality of flow guiding elements for locally increasing the turbulence and flow rate of the coolant passing through the contact portion. The invention also relates to a system comprising the apparatus and the tool, and a cooling method using the system. Background Technology

[0002] This invention relates to the field of industrial manufacturing, and more particularly to machining workpieces using a turning tool.

[0003] In industrial manufacturing processes, such as turning, effective cooling strategies are of paramount importance to reduce the heat generated between the tool and workpiece during chip formation. To date, the most common method in metalworking is flood cooling using a cooling lubricant. In this method, the cooling lubricant is supplied at a volumetric flow rate of several hundred liters per hour to cool the tool and / or workpiece, applied as close as possible to the machining area between the tool and workpiece through external nozzles. Failure to meet these conditions during turning results in insufficient cooling lubrication. Furthermore, the excessive use of cooling lubricants limits their lifespan, leads to high maintenance and disposal costs, and imposes a significant economic and health burden on businesses.

[0004] In recent years, specific cooling strategies, such as minimum quantity lubrication and cryogenic cooling, have been developed to reduce the use of cooling lubricants while ensuring efficient cooling. All processes are constantly evolving to achieve the most sustainable production. However, they still retain inherent disadvantages, such as high energy and resource consumption and cost-intensive handling of materials. Therefore, research and development are increasingly focused on innovative methods to improve cooling in industrial manufacturing processes, thereby achieving the most sustainable production possible.

[0005] To overcome the drawbacks of insufficient process control and non-reproducible performance, a novel closed-loop cooling strategy can be employed, eliminating the need for external coolant lubricants in the machining area. Therefore, heat generated during machining is dissipated both through chips and through enclosed internal cooling. Heat conduction in internal cooling occurs indirectly through conduction and forced convection, enabling targeted and uniform cooling of the tool by the coolant, thereby improving temperature control and process stability. Furthermore, internal cooling significantly reduces the demand for coolant lubricants, thus lowering associated storage and disposal costs.

[0006] Generally, methods and systems capable of internal cooling using closed loops are known. The following prior art exists in this field:

[0007] DE 19730539C1 describes a heat sink located within an improved tool holder, featuring a segmented and plate-like microstructure with channel dimensions less than 300 micrometers to improve cooling efficiency. Heat conduction occurs through a material with good thermal conductivity on the tool's bottom surface. The heat sink can be positioned on opposite sides.

[0008] WO 2018046489A1 describes an improved tool holder that enhances cooling and temperature control of cutting inserts. The tool includes a cutting plate and a cooling system. The cooling system consists of a dual-pipe system that simultaneously supplies and discharges coolant. This dual-pipe system specifically directs the cooling medium to the underside of the tool.

[0009] SU 795883 A1 describes a tool holder or turning tool with internal cooling, having a housing with an axial channel. This channel is connected to a tube made of a thermally conductive material, partially filled with a coolant, such as water. Heat is dissipated from the cutting plate and transferred to a more distant cooler area by evaporating the coolant. The tube is hinged to the inner cavity and can be adjusted at various angles to allow cooling at any location on the tool holder or turning tool.

[0010] The aforementioned technologies require adaptation to tools or tool holders, and their standardized interfaces and geometries do not represent suitable industrial solutions. Furthermore, the cooling performance regarding flow parameters and heat transfer mechanisms has not been investigated. Therefore, a novel industrially applicable cooling strategy is needed, building upon existing technologies, to more effectively remove heat from tools, improving the energy efficiency of tool systems without requiring modifications to the tools or tool holders.

[0011] Purpose of the invention

[0012] The purpose of this invention is to provide a technical solution for cooling tools that avoids the release of toxic or irritating coolants into the environment and reduces the consumables required for cooling. Another object of this invention is to provide an economical solution for cooling tools that ensures high and repeatable cooling performance and allows the coolant to be placed particularly close to the heat dissipation contact area between the tool and the workpiece. Summary of the Invention

[0013] This objective is achieved through the features of the independent claims. Advantageous embodiments of the invention are described in the dependent claims.

[0014] In a first aspect, the present invention relates to an apparatus for cooling a tool, the apparatus comprising a base, a contact element, at least one inlet into the base, and an outlet from the base. The inlet and the outlet are connected to each other via one or more internal channels in the base. The apparatus is connectable to the tool such that the contact element contacts the tool. The one or more internal channels are used for the conduction of coolant. The one or more internal channels include contact portions, wherein the contact portions contact the contact element to achieve heat conduction. The contact portions include a plurality of flow guiding elements configured to change the flow rate and locally increase the turbulence of the coolant through the contact portions, thereby resulting in increased heat transfer from the contact element.

[0015] Coolant can be continuously conducted through the equipment via internal channels within the equipment's base. Therefore, the coolant can be maintained in a closed loop for cooling the equipment and connected tools, preventing its uncontrolled release into the environment. Furthermore, a closed loop through which environmentally friendly coolant flows is preferably provided, eliminating the need to introduce external cooling lubricant into the processing area. Thus, the health and safety risks of conventional diffused cooling can be completely eliminated from the cooling process. Personnel are not exposed to the coolant, and there is no risk of leakage that could contaminate workpieces and machine surfaces. This also reduces the consumables required for cooling. Because the internal channels can be connected to external systems to form a closed fluid loop, significantly less coolant can be used over a longer period before replacement is necessary (e.g., compared to diffused cooling). This is particularly economical and environmentally friendly.

[0016] Because the device according to the invention can be connected to the tool, the coolant flowing in the internal channels can be brought particularly close to the tool. Specifically, the coolant can be very close to the contact area between the tool and the workpiece. Since this is the area where most of the heat is generated, the cooling process is more efficient due to this close contact. This is particularly advantageous compared to flood cooling systems, in which the coolant typically cannot reach this area or evaporates into the environment before reaching it.

[0017] Another advantage of the invention is that the device for cooling the tool is a component independent of the tool itself. While the device according to the invention can be connected to a tool, the tool does not necessarily have to be part of the device. Therefore, the device can be used directly with any suitable tool without modification. The tool does not need to be modified for connection to the device, meaning in particular, that the tool itself does not need modification. This means it is advantageous that no new tool needs to be implemented to adapt to an established machining process. Furthermore, the strength of the tool is not adversely affected because there is no need to run channels inside the tool. Additionally, the coolant circuit does not need to be interrupted when changing the tool, thus preventing contamination or leakage. Since the tool is typically a frequently replaced consumable part, it is economically advantageous to implement the cooling solution provided by the invention without modifying this part. Instead, the device itself can be manufactured or modified to include the internal channels and flow guiding elements according to the invention. Since the device does not participate in the machining process, it experiences less or even no wear compared to the tool. Therefore, the device can be reused over a longer service life. Thus, long-term modifications applied to the base material are more economical than modifications applied to worn parts. The tool holder for securing tools and connecting equipment requires no modification, which in particular means that no drilling or similar alterations to the tool holder are required, thus eliminating the need to replace or modify existing tool holders. Tools do not require recalibration, which advantageously means that installation time is not significantly increased. The continued use of existing tool holders and the lack of a significant increase in installation time make this invention very economically attractive. Furthermore, the coolant circuit does not need to be interrupted when changing the tool holder. In particular, components independent of the tools and tool holders can be easily transferred from one tool to another. This advantageously allows the use of the device according to the invention with different tools without the need for individual adjustment of each tool. However, it is possible, but not excluded, that channels for coolant are also integrated into the tools or tool holders.

[0018] For example, a tool holder may be provided including a flow channel, wherein a flow within the tool holder flows along a surface in contact with the tool. The coolant inlet and / or outlet can be located on any surface of the tool holder. However, it can also be connected to a cooling unit, a base, and / or clamping fingers. Thus, coolant inlets and outlets can be provided leading to the flow channel within the tool holder, through the device for cooling the tool, and / or directly on the tool clamp. Additional flow channels within the tool holder can advantageously promote particularly effective cooling performance.

[0019] The presence of the substrate in the device allows for a convenient three-dimensional shape, which can enable secondary functions, such as acting as gripping fingers. Furthermore, the substrate provides an internal space in which the internal channels can be freely arranged, for example, on different planes and with different angles of incidence relative to the contact portion. Since the substrate is a separate component from the contact element, these two components can use different materials; the substrate material can be chosen for ease of processing or particular economic efficiency. In contrast, the contact element material can be designed for maximum thermal conductivity and extremely high heat resistance.

[0020] The contact elements are arranged such that they contact the tool when the device is connected to it. Therefore, the material for the contact elements can be specifically selected for this purpose. Since materials with extremely high conductivity can be expensive, it is advantageous to separate the contact elements from the substrate of the device.

[0021] However, the contact element and the substrate can also be made of the same material, thus forming a monolithic structure for overall heat conduction. If the contact element and the substrate are made of the same material, the wall thickness of the contact element can be ≤ 1 mm, preferably ≤ 0.5 mm, and particularly preferably ≤ 0.2 mm.

[0022] The overall structure advantageously reduces the number of manufacturing steps required and allows for great flexibility in the geometry of the contact elements and / or the contact surfaces between the tooling and the cooling equipment. Whether by eliminating assembly steps and connection processes or by using cheaper materials for the contact elements, the reduction in the number of manufacturing steps advantageously lowers production costs. Heat transfer is further improved by reducing the amount of material in contact with each other, which helps to achieve a particularly efficient cooling process. This also allows for the use of smaller flow-guiding elements in the contact areas.

[0023] With the contact element and substrate being an integral structure, the wall thickness is ≤1mm, which advantageously enables efficient heat transfer from the tool to the coolant, and mainly features high wall stability.

[0024] When the contact element and the substrate are an integral structure, a wall thickness of ≤0.5 mm is preferred, which advantageously provides a particularly excellent ratio, ensuring both efficient heat transfer to the coolant and maintaining high strength. This configuration is particularly preferred when the cooling device is used as a clamping finger.

[0025] When the contact element and the substrate are an integral structure, a wall thickness of ≤0.2 mm is particularly preferred, which advantageously leads to an increase in heat flux in the coolant, which is comparable to the effect achieved by a separate contact element with a larger wall thickness that does not form an integral unit with the substrate.

[0026] System peripherals can be connected to the inlet and outlet of the base. These peripherals may include commercial components (pumps, hoses, condensers / cooling units) or customer-specific arrangements for continuously pumping coolant into the equipment. The coolant preferably circulates in a fluid loop. Therefore, even if the coolant evaporates as it flows through the equipment, it will not leak into the atmosphere. This eliminates health risks and is particularly environmentally friendly.

[0027] By providing contact portions to the internal channels of the device that come into contact with the contact elements, these portions can be dedicated to maximizing heat exchange. Multiple flow-guiding elements within the contact portions of the internal channels cause localized contraction of the cross-section of the contact portions, resulting in a localized increase in flow velocity. The shape and position of the flow-guiding elements can be further selected to induce vortices in the coolant, thereby increasing turbulence at the contact portions.

[0028] The increased flow rate and increased turbulence synergistically contribute to increasing the heat transfer rate of the tool through the contact elements into the coolant, particularly by increasing the turbulent kinetic energy along the contact portion. Compared to the prior art, this improves the heat dissipation rate of the tool and yields surprising results for the solution according to the invention.

[0029] However, it can also be specified that the flow from the inlet through the contact section and then through the outlet can function without the need for additional flow guiding elements within the contact section. In this case, the inlet, contact section, and outlet are preferably used together as flow guiding elements. This advantageously enables particularly simple and economical production of equipment for cooling tools with low flow resistance.

[0030] In the context of this invention, "device for cooling a tool" is preferably a device that can be used in conjunction with a tool to reduce the tool temperature during workpiece machining, particularly during workpiece turning. Preferably, the device is used to reduce the localized temperature of the tool at the point of contact between the tool and the workpiece.

[0031] In the context of this invention, the "substrate" is preferably a three-dimensional unit, substantially composed of a homogeneous material, and provided with an inlet, an outlet, and an internal channel including a contact portion. Preferably, the substrate has a larger dimension than the contact element. Particularly preferably, the thickness of the substrate is at least two times, preferably at least three times, the thickness of the contact element, wherein the thickness is measured along a direction from the surface of the tool through the contact element and through the substrate. Preferably, the length of the substrate is at least 110%, preferably at least 120%, of the length of the contact element, and the length is preferably measured along the main flow direction through the contact portion. Preferably, the width of the substrate is at least three times, preferably at least five times, the width of the contact element. The substrate may preferably be provided with a groove for receiving the contact element, such that the substrate surrounds the contact element from above and from one or more sides. Generally, the substrate may surround one or all surfaces of the contact element, but excluding the surface for contact with the tool.

[0032] In the context of this invention, the "contact element" is preferably a plate made of a material that ensures a higher thermal conductivity than the substrate material. The contact element is also preferably particularly heat-resistant. The contact element is used to contact a tool on at least one of its surfaces, preferably through direct mechanical contact. Opposite surfaces of the contact element are used to contact a contact portion of an internal channel of the substrate. This opposite surface may also form part of the contact portion, particularly its bottom surface. Alternatively, the opposite surface of the contact element may contact a separate solid bottom surface of the contact portion, formed of the substrate material or other materials. Preferably, the length and / or width of the contact element may also be greater than the contact portion, such that it contacts the material of the substrate at the boundary of the contact portion.

[0033] In the context of this invention, an "internal channel" is preferably a cavity that extends between the inlet and outlet of the substrate and defines the flow direction along its longitudinal axis. The cross-section of the internal channel can take any form and can vary along the flow direction.

[0034] In the context of this invention, the "contact portion" is preferably a cavity or recess in the substrate, through which coolant guided by internal channels is directed along its path between the inlet and outlet. The contact portion contacts a contact element, preferably in direct contact. In the case of direct contact, for example, the bottom surface of the contact portion is in mechanical contact with the contact element, or the contact element forms the bottom surface of the contact portion, such that no additional components are inserted between the cavity of the contact portion and the contact element. This supports rapid heat transfer from the contact element to the coolant.

[0035] In the context of this invention, the "flow guiding element" is preferably a three-dimensional geometric element (also referred to as a "geometry") that produces a localized contraction in the cross-section of the contact portion. The flow guiding element is connected to or protrudes from at least one inner wall of the contact portion. For example, the flow guiding element is connected to the bottom surface, side wall, or both side walls of the contact portion. The flow guiding element preferably has a geometry that increases turbulence at least locally in the contact portion, and preferably increases the turbulent kinetic energy in the region adjacent to the contact element. The flow guiding element can exhibit a regular or irregular geometry.

[0036] In a preferred embodiment of the invention, the contact element forms the inner wall of the contact portion, wherein one or more flow guiding elements are also preferably in contact with the contact element, permanently connected to the contact element, or form part of the contact element. Preferably, the plurality of flow guiding elements are configured for heat conduction from the contact element to the coolant. Particularly preferably, the flow guiding elements are composed of the same material as the contact element or an alternative material having high thermal conductivity. This advantageously achieves particularly efficient heat conduction and uniform temperature distribution.

[0037] When the contact element forms the inner wall of the contact portion (especially the "bottom surface"), the contact between the contact element and the coolant is established without an additional layer. This allows the coolant to be brought closer to the tool, particularly to the hottest contact area. Due to the high thermal conductivity of the contact element, its temperature is equal to or very close to the tool's temperature. A high temperature gradient is achieved between the contact element and the coolant, supporting high heat flux and excellent cooling.

[0038] Heat transfer from the tool to the coolant can be increased by bringing one or more flow guide elements into contact with, permanently connecting to, or forming part of the contact element. The contact area between the contact element and the coolant can also be increased because flow guide elements can have more complex geometries and a larger surface-to-volume ratio than contact elements.

[0039] In another preferred embodiment of the invention, the flow guiding element protrudes from the inner wall of the contact portion, particularly from the bottom surface or the contact element itself. Preferably, the flow guiding element forms a partial contraction in the cross-section of the contact portion. Preferably, at least one surface of the flow guiding element forms an exterior angle of 90° to 175° with the inner wall of the contact portion, particularly 100° to 150°. The interior angle is preferably between 5° and 90°, particularly between 30° and 80°, and especially preferably between 40° and 60°. The surface of the flow guiding element preferably faces downstream. The surface of the flow guiding element facing upstream may also exhibit interior and exterior angles within the same preferred range, and the upstream surface can have the same angle as the downstream surface, particularly in the case of isosceles triangular prisms, circular triangular prisms, or symmetrical trapezoidal prisms.

[0040] Surprisingly, the flow guide element with the aforementioned preferred angle leads to flow separation, resulting in forced vortex formation. Furthermore, positioning the flow guide element on the bottom surface of the contact portion, particularly on the contact element itself, causes vortices to form near the contact element, significantly increasing turbulent kinetic energy in that region. This helps maintain a high temperature gradient between the contact element and most of the coolant.

[0041] Therefore, these preferred shapes and angles result in particularly advantageous flow dynamics optimization and improved heat transfer through turbulence in the flow. Due to the preferred angles, dead zones (areas where coolant stagnates) can be advantageously minimized, thereby promoting a particularly uniform distribution of coolant.

[0042] In another preferred embodiment of the invention, the flow guiding elements are positioned along one or more inner walls of the contact portion. Preferably, one or more flow guiding elements are arranged such that at least one surface of them receives impact from the coolant flowing along the contact portion and / or through the coolant entering the contact portion, preferably to guide the coolant to the contact element. This facilitates particularly effective cooling of the contact element.

[0043] In another preferred embodiment of the invention, at least one flow guiding element is connected to two parallel inner walls of the contact portion. Preferably, the flow guiding element is simultaneously separated from the remaining inner walls of the contact portion, specifically such that a gap is formed between the flow guiding element and the contact element. The two parallel inner walls connected to the flow guiding element are preferably substantially orthogonal to the contact element. In the context of this invention, such a flow guiding element is referred to as an "exposed flow guiding element".

[0044] The use of exposed flow guides enables the generation of additional secondary flows, particularly through the gap between the exposed flow guides and the bottom surface of the contact portion, thereby locally increasing flow velocity and turbulence. This further enhances heat transfer.

[0045] In another preferred embodiment of the invention, one or more inner walls of the contact portion include at least one cavity. The cavity preferably represents a partially enlarged cross-section of the contact portion, wherein each cavity is preferably defined by a break edge. The break edge preferably forms an exterior angle between 90° and 175° relative to its respective inner wall.

[0046] Preferably, the cavity comprises a material different from the substrate. For example, the cavity may include inserts or coatings of other materials, preferably having higher thermal conductivity than the substrate material. Preferred materials for the cavity include copper, diamond, silver, or combinations thereof. These materials can advantageously remove heat particularly quickly.

[0047] Alternatively, the cavity may be preferably located between the feed channels or between the feeder and the discharge device in contact with the feeder.

[0048] The break edge of the cavity has a positive effect on flow separation and can be adjusted by changing the obtuse outer angle relative to the inner wall of the contact portion. Furthermore, this can be achieved by moving the break edge in the direction of the feed channel or in the direction of the subsequent cavity, particularly by moving the tip of the break edge.

[0049] Vortices can form within the cavity, thereby generating turbulence. The break edge of the cavity can promote vortex formation, wherein the outer angle of the upstream break edge is preferably between 90° and 175°. Orthogonal or lower outer angles, such as angles between 90° and 120°, can generate impinging flows, thereby producing particularly strong vortex formation. The angle of the upstream break edge can also be used to guide coolant to the contact element so that the coolant impinges on the bottom surface region of the contact portion and forms vortices near the contact element.

[0050] It is also shown that the combined use of cavities and flow guiding elements synergistically increases turbulence along the contact portion. Specifically, cavities and flow guiding elements can be provided within the contact portion between feed channels or between feed and discharge channels to accommodate coolant flow, thereby improving heat flux and cooling performance. By integrating cavities and flow guiding elements, the temperature within the coolant is uniformly distributed across the entire cross-section of the contact portion.

[0051] Furthermore, due to the separation effect and vortex formation equivalent to impinging flow, the cavity and guide elements cause forced deformation of the flow. The separation effect and vortex formation cause the mainstream to be guided towards the lower side of the contact portion (especially towards the contact element).

[0052] Furthermore, the cavity and flow guiding elements allow for targeted adjustment of the flow cross-section at the contact point, which has a positive impact on flow velocity and turbulence behavior related to cooling performance.

[0053] In a preferred embodiment of the invention, coolant is supplied to the contact portion through a single inlet channel and discharged from the contact portion through a single outlet channel. Preferably, in such an embodiment, multiple cavities are arranged along the inner wall of the contact portion between the inlet and outlet channels. This makes it possible to achieve a remarkably effective turbulence effect with minimal pressure loss.

[0054] The length of the cavity along the longitudinal axis of the flow direction or the contact portion can be selected to control the turbulence effect. Preferably, the cavity length is designed to increase turbulence at the bottom surface of the contact portion or at the contact element.

[0055] In a preferred embodiment of the invention, the contact portion includes a plurality of cavities, each cavity having a length not less than 2% and not more than 40% of the contact portion length. Preferably, the length of each cavity is between 6% and 30% of the contact portion length, particularly between 15% and 25%. Preferably, the height (also referred to as “depth”) of each cavity is not less than 10% and not more than 85% of the contact portion thickness. Preferably, the cavity height is between 30% and 60%, particularly about 45% of the contact portion thickness. A greater cavity height may also preferably increase the surface- or volume-based proportion of turbulent eddies, thereby enhancing the effect of forced turbulence. These preferred dimensions have proven particularly suitable for increasing turbulence along the contact portion. Furthermore, the preferred dimensions can advantageously contribute to a particularly advantageous combination of cooling performance and high structural integrity.

[0056] In the context of this invention, a "cavity" is preferably a groove in one or more inner walls of the contact portion, the groove partially enlarging the cross-section of the contact portion. The cavity preferably has a bottom or top surface located at the deepest point of the groove, the bottom or top surface preferably extending substantially parallel to the corresponding inner wall of the contact portion. Other embodiments of cavities without a distinguishable bottom or top surface may also be preferred, for example, when the deepest point of the groove is merely a point between the break edges. This is particularly true when one or more break edges of the cavity have a very gentle slope.

[0057] In another preferred embodiment of the invention, to achieve the desired backflow of coolant in the contact portion and increase turbulence, an interior angle between 5° and 60° is formed at the downstream-facing break edge of the cavity. This angle smooths the slope between the inner wall of the contact portion and the deepest point of the cavity. Preferably, the downstream-facing break edge seamlessly transitions from its deepest point back to the height level of the inner wall via the interior arc of the upstream angle of the cavity. This arrangement has proven to be particularly effective in increasing turbulence.

[0058] In some preferred embodiments of the invention, as described above, the exposed flow guiding element is disposed within the cavity along with the break edge and the internal curvature. Preferably, the exposed flow guiding element is located in the region of the curvature.

[0059] In another preferred embodiment of the invention, as described above, the cavities having broken edges, gentle slopes, and rounded inner corners are arranged directly in sequence as described above.

[0060] In the context of this invention, a “break edge” (also known as a “jumping edge”) preferably refers to the transition from the inner wall of the contact portion to the deepest point of the cavity, particularly the bottom or top surface of the cavity.

[0061] In another preferred embodiment of the invention, the flow guiding element has a prism shape, a pyramid shape, a polyhedral shape, a sphere shape, or an ellipsoid shape, or a combination thereof. "Combination thereof" preferably indicates that the same flow guiding element exhibits different shape characteristics. It is also preferable to use flow guiding elements with different shapes in the contact portion.

[0062] Preferably, the flow guiding elements are shaped such that they include at least a first inclined or curved surface upstream and at least a second inclined or curved surface downstream. However, the number of surfaces of the flow guiding elements is not limited. Particularly preferably, at least some of the flow guiding elements have a prism shape with an isosceles triangular cross-section, preferably with rounded tips. The prism shape is preferably orthogonal to the longitudinal axis of the contact portion, such that the first side of the triangle faces upstream, the second side of the triangle faces downstream, and the third side of the triangle faces the base or is connected to the base of the contact portion or the contact element. Preferably, the interior angle between the third side and the first side of the triangle is between 5° and 85°, particularly between 5° and 60°. Preferably, the interior angle between the third side and the second side of the triangle is within the same preferred range. This allows for the generation of particularly advantageous turbulence while advantageously simplifying manufacturing.

[0063] In a preferred embodiment of the invention, the interior angle of the triangle between the first and third sides (i.e., upstream) is greater than the interior angle of the triangle between the second and third sides (i.e., downstream). This allows for the impingement flow of coolant on the guide element, and subsequently the guidance of coolant (e.g., from the feed channel or from the cavity) toward the contact element.

[0064] The flow separation generated by the flow guiding element can be modified, in particular by adding features such as curvature between the first and second sides of the triangular cross section, thereby adjusting the turbulence.

[0065] In another preferred embodiment of the invention, the height-to-width ratio of the guide element is between 1:10 and 3:1. This provides a surprisingly effective balance between the localized reduction in the cross-section of the contact portion and a suitable incident angle between the coolant and the guide element. In selecting the shape and size of the guide element, it is particularly preferred that the outer angle of the upstream-facing surface of the guide element is no greater than 175°, or the inner angle is at least 5°. This achieves impingement flow.

[0066] In another preferred embodiment of the invention, a highly thermally conductive ductile material, such as a copper alloy, may be advantageous for the flow-guiding element. Furthermore, geometries such as cylinders, prisms, irregular sponge-like shapes, or airfoil profiles can be precisely realized at the contact portion.

[0067] In another preferred embodiment of the invention, the flow guiding elements locally reduce the cross-section of the contact portion by at least 20%, and particularly at least 30%. Therefore, the flow guiding elements do not merely represent irregularities on the inner surface of the contact portion. Rather, they are individual elements with significant dimensions, capable of significantly redirecting the flow of coolant. This can advantageously increase the flow rate. Furthermore, this can advantageously achieve a particularly uniform temperature distribution.

[0068] In another preferred embodiment of the invention, the contact element comprises a thermal conductivity of at least 100 W / m. -1 K -1 Materials with a melting point greater than 600°C are preferred, and these materials are preferably selected from diamond, copper, gold, silver, aluminum, or alloys of copper, gold, silver, or aluminum. Diamond is particularly preferred. These preferred materials have proven to be particularly effective for transferring heat from the tool to the coolant. At the same time, these materials exhibit high heat resistance and mechanical strength resistant to tool vibration.

[0069] The contact element is connected to the substrate, for example, by clamping, threading, or welding, but preferably by bonding. Preferably, the contact element is integrated into the substrate, forming the bottom surface of the contact portion. More preferably, the contact element makes direct surface contact with the tool. Considering the thermal and mechanical properties of the contact element, it is preferably designed to be as thin as possible. Using one of the preferred materials allows for the lowest possible thermal delay.

[0070] In another preferred embodiment of the invention, the thickness of the contact element is 2 mm, particularly 0.5 mm. At such a thickness, the thermal delay of the contact element can be kept particularly low, thereby allowing heat to be efficiently transferred from the tool to the coolant. By minimizing the thickness of the contact element, the heat flux of the tool into the contact portion is additionally increased according to Fourier's law. Given the properties of the chosen material, the temperature of the tool, and the temperature of the coolant, those skilled in the art can select a suitable contact element thickness to maintain low thermal delay while maintaining high thermal conductivity.

[0071] The temperature difference of the contact element along the flow axis in the contact portion is preferably no more than 20K, and especially no more than 5K.

[0072] In another preferred embodiment of the invention, the surface roughness of the contact element facing the contact portion is between 0.1 µm and 200 µm, particularly between 25 µm and 50 µm. Such roughness corresponds to the grain size of the untreated CVD diamond layer. The surface roughness of the contact element increases thermal conductivity to the coolant.

[0073] In another preferred embodiment of the invention, the distance between the contact element and the contact surface of the tool is chosen to be as small as possible. Preferably, this distance does not exceed half the distance between two symmetrically opposite tool edges.

[0074] Preferably, the surface roughness of the contact element facing the tool is less than 0.1 µm, particularly between 0.01 and 0.06 µm. This surface is preferably polished. This achieves optimal, gapless contact between the contact element and the tool, thereby enabling good thermal conductivity.

[0075] In another preferred embodiment of the invention, the surface of the tool-facing contact element covers at least 10% and up to 100% of the tool surface area. Particularly preferably, the contact element contacts at least the rake face of the tool. Also preferably, the other surface of the tool-facing contact element occupies between 10% and 100% of the tool surface to be cooled. This allows for the targeted use of more expensive materials such as diamond, while the contact portion can be limited to generate a higher flow rate.

[0076] Preferably, the "surface to be cooled" of the tool is the rake face, the flank face, and / or the surface in contact with the tool holder. Particularly preferably, the surface to be cooled is the rake face.

[0077] The internal channels of the equipment can be divided into different sections according to the flow direction, especially the contact elements. One or more sections of the internal channels that supply coolant to the contact elements from the inlet can be called "feed channels" or "feeders". One or more sections of the internal channels that discharge coolant from the contact elements can be called "discharge channels" or "dischargers". The contact section is preferably located between the feed channels and the discharge channels that contact the contact elements.

[0078] In another preferred embodiment of the invention, one or more internal channels include one or more, preferably 1 to 15, particularly preferably 3 to 8, feeders and one or more dischargers. Preferably, the feeders are arranged on a feeder plane above the discharge plane occupied by the contact portion and / or the dischargers. The arrangement of the feeders and dischargers on different planes is preferably achieved by sufficient dimensions of the base. It should be noted that the feeders do not need to run parallel to the dischargers. Instead, they can enter the contact portion from different planes. Furthermore, the feeders and dischargers can be straight or spatial routes. Thus, the feeders can run at least partially inclined relative to the contact element, such that coolant can impact the bottom surface of the contact portion, which may be formed by the contact element itself. When the contact element forms the lower part of the device, the "feeder plane" is preferably a higher plane than the "discharge plane".

[0079] In another preferred embodiment of the invention, the feeder enters the contact portion, and the flow direction of the feeder is preferably set at an angle of 0° to 90°, particularly 30° to 60°, relative to the surface of the contact element facing the tool. Preferably, the flow direction is considered in a plane orthogonal to the surface of the contact element.

[0080] By feeding the coolant into the contact portion orthogonally or obliquely at a preferred angle, an impinging flow is generated at the contact element. Furthermore, the shape, size, and position of the guide element and / or cavity can synergize with the oblique feeding to ensure increased turbulence in the contact portion. The guide element causes flow separation, thereby inducing forced turbulence. The guide element can be particularly preferably positioned opposite the feed channel and / or one or more cavities. This may mean that the guide element is located on the bottom surface of the contact portion, while the feeder or cavity is located at the same longitudinal position on the top surface of the contact portion. Alternatively, this may mean that the guide element is exposed within the feed channel or cavity. Such an arrangement allows the guide element to be impinged by the feeder or cavity and along the main flow direction of the contact portion, thereby further increasing turbulence.

[0081] The feeder and discharger cross-sections can have any desired shape, such as circular, elliptical, rectangular, or freeform. Circular or elliptical cross-sections are particularly preferred. Such cross-sections allow for laminar flow and minimize pressure loss due to friction between the coolant and the channel walls.

[0082] In another preferred embodiment of the invention, the diameter of the feeder and / or discharger is between 0.1 mm and 5 mm, preferably between 0.3 mm and 3 mm, and especially between 0.5 mm and 2 mm. Such a small diameter results in a very high flow rate relative to the volumetric flow rate of the coolant used. Therefore, the cooling process becomes surprisingly efficient.

[0083] In another preferred embodiment of the invention, the feeder is designed to be conical. This reduces pressure loss along the feeder and increases the flow rate of coolant into the contact portion.

[0084] Preferably, the feeder includes thermal insulation, for example in the form of a suitable coating, and / or is configured to minimize convection losses. The material of the substrate and / or its coating may also be used for the feeder's insulation. This insulation prevents unwanted heating of the coolant and condensation due to ambient temperature. Therefore, the temperature difference between the coolant and the contact elements in the contact portion can be maximized.

[0085] Preferably, at least one feeder and one discharger are present for conveying coolant through the contact portion. Compared to, for example, concentric orifices, this advantageously reduces the operating pressure required in the cooling circuit due to the larger cross-section resulting from the separation of the feeder and discharger. This is particularly advantageous when the flow rate is varied to increase heat conduction. The feeder and discharger can be arranged horizontally, vertically, or at any desired angle to each other. This advantageously provides flexibility in designing the cross-sections of the feeder and discharger within the substrate. The cross-sections of the feeder and discharger are preferably as large as possible to maximize the volumetric flow rate of the coolant at the maximum permissible operating pressure.

[0086] In another preferred embodiment of the invention, the invention includes one to three discharge devices from the contact portion, with a single discharge device being particularly preferred. The cross-section of the discharge device is preferably chosen to be as large as possible, but should not exceed twice the cross-section of the substrate outlet. Preferably, the cross-section of the discharge device does not exceed the cross-section of the outlet. This ensures lower system pressure at the outlet. It is also preferable that the flow through the discharge device and / or from the substrate outlet is laminar. This reduces the pressure differential and load on downstream components of the system peripherals used for coolant treatment.

[0087] In another preferred embodiment of the invention, the cross-section of the discharge device is equal to or greater than the cross-section of a single feeder. Particularly preferred is that the cross-section of the discharge device does not exceed the sum of the cross-sections of all the feeders. Preferably, when viewed from any direction, the discharge device preferably extends to the longitudinal end of the contact portion, preferably within the last 30% of the length of the contact portion.

[0088] Preferably, the feeder and discharger are connected to the contact portion at one end and to the inlet or outlet of the substrate at the other end. The inlet and outlet preferably each include a connector for connecting the device to the system periphery.

[0089] In some preferred embodiments of the invention, the device includes a plurality of contact elements and a plurality of contact portions, such as at least two contact elements having two associated contact portions, at least three contact elements having three associated contact portions, or more. It is also preferable that the number of contact elements does not correspond to the number of contact portions; for example, multiple contact portions may contact different areas of the same contact element.

[0090] In another preferred embodiment of the invention, the contact portion includes a longitudinal axis. In this embodiment, the contact portion includes a plurality of feeders, wherein a first feeder approaches the contact portion at a lateral distance different from the longitudinal axis of the contact portion compared to a second feeder. In other words, two or more feeders enter the contact portion at different lateral positions. The lateral distance of the center of each feeder cross-section can deviate from the longitudinal axis of the contact portion (also referred to as the "centerline"). Preferably, the center of the cross-section of no feeder extends beyond the bottom surface of the contact portion. By changing the lateral position of the feeders, vortices can be formed throughout the contact portion because the flow from one feeder impacts the flow from another feeder. This further increases turbulence and cooling rate.

[0091] In yet another preferred embodiment of the invention, all feeders are directed toward the longitudinal axis of the contact portion. This may result in more predictable flow conditions, where the feeder's impact angle, guide elements, and / or cavities determine the formation of vortices.

[0092] If multiple feeders are used, the spacing between the feed channels can be selected as needed. Preferably, the feeders are equidistant longitudinally at the contact points. Similarly, the distance between one feeder and the next feeder may also vary.

[0093] The contact portion can have any desired shape, wherein the minimum dimension of the contact portion is its thickness. The contact portion preferably has a longitudinal axis representing the primary flow direction. Preferably, the feeder is disposed along the longitudinal axis (optionally offset thereto), while the discharger is disposed near one end of the longitudinal axis. The cross-section of the contact portion is preferably the dimension of its opening in a plane transverse to the longitudinal axis. Preferably, the cross-section of the contact portion is between 0.008 mm² and 20 mm², particularly between 0.2 mm² and 3.5 mm². If the cross-section varies along the length of the contact portion, these values ​​preferably represent an average value.

[0094] The bottom surface (or "base surface") of the contact portion can be circular, elliptical, or rectangular, or designed in a free form. Preferably, the bottom surface is rectangular, and the edges of the contact portion can be rounded. This can reduce pressure loss.

[0095] In another aspect, the present invention relates to a system for cooling a tool used to process a workpiece as described in any of the preceding claims, and to the tool and means for connecting a device to the tool. Furthermore, the system includes a fluid circuit for delivering coolant to an inlet and directing coolant from an outlet of the device to cool the tool.

[0096] The system according to the invention is based on a closed loop, which is preferably traversed by an environmentally friendly coolant. Therefore, coolant lubricant (KSS) cannot be supplied to the outside of the cutting zone. Heat generated during machining is partially dissipated by cutting and partially by the enclosed internal cooling system. Heat transfer to the internal cooling system occurs indirectly through conduction and forced convection. This is achieved through contact between the tool and the cooling equipment, and through the coolant flowing through the equipment and the fluid circuit ("part of the system periphery").

[0097] The fluid loop is preferably used for handling, moving, and / or temperature-controlling coolant. One advantage is that the coolant is kept within the fluid loop. Therefore, the system's operating costs are significantly reduced compared to flood cooling. Furthermore, the limited cross-section of the fluid loop and the internal channels of the equipment are used to increase flow velocity and flow pressure. The required pressure and volumetric flow rate are reduced by 100 times compared to flood cooling. Therefore, the pump power of the fluid loop can be significantly reduced. In addition, the amount of coolant required is much less. The coolant requirement can be 10 times lower than that of flood cooling. Significant advantages in energy and resource consumption are also achieved due to the closed-loop design and targeted heat extraction.

[0098] The connection between the device and the tool is preferably releasable. For example, it may include screws, preferably passing through the base, contact element, and tool. When using screws to connect the device to the tool, the screws preferably serve to secure both the device and the tool simultaneously. This advantageously reduces the number of additional components. Furthermore, particularly precise positioning of the device relative to the tool can be achieved. Additional screws or individual screws for connection may also be provided. This advantageously provides particularly high flexibility in the use and / or positioning of the device. Alternatively, the device may also be connected to the tool by clamping or engaging. This advantageously allows for particularly flexible and simple positioning of the device. The device can be used as a clamping finger or as an additional component without interfering with any existing clamping system. Cooling devices may be positioned above, below, or in combination with the tool. The terms "above" and "below" refer to the typical orientation of the tool when used with a workpiece. This positioning is well known to those skilled in the art.

[0099] The device can also be positioned laterally and / or on multiple surfaces of the tool. This advantageously allows for particularly efficient cooling of the tool. Multiple surfaces can be cooled simultaneously, for example, by using multiple cooling elements and / or a single cooling element that can extend across multiple surfaces.

[0100] Depending on its intended use, the device can also have dual functions, such as clamping and / or cooling. This advantageously minimizes the number of components used, thereby minimizing the negative impact of the cooling equipment on process behavior. In particular, it can advantageously avoid impacts on the vibration behavior of the tool holder and the depth of cut (a). p The negative impact of installation time and / or time.

[0101] Alternatively, the device can be an additional component that has no function other than cooling within the tool system and does not affect the existing clamping system. This makes it particularly easy to integrate the device into existing tool systems.

[0102] In a preferred embodiment of the invention, the system includes a tool holder, wherein a cooling device is used as or integrated into the tool holder. According to this embodiment, the device can cool the tool from below.

[0103] The advantage of this system is that it requires no modification to the tools, tool holders, or optional tool stands. Therefore, maintenance utilizes standardized components such as tools and tool holders.

[0104] In another preferred embodiment of the invention, the cooling device is configured as a tool holder, which is preferably designed to cool the tool from below. This configuration can also be additionally combined with another cooling device configured as a gripping finger, or connected to the tool from above, so that the tool is cooled from both above and below. Such cooling devices can interact synergistically to reduce the temperature of the tool.

[0105] In another preferred embodiment of the invention, the device for cooling the tool is used as a clamping finger of the clamping tool. In this case, the device can be integrated into the clamping finger. The clamping finger can also be modified to achieve the features of the device.

[0106] Preferably, the body of the device comprises a metallic material. However, it may also additionally have a thermal insulation layer. When the device is used as a gripping finger of a clamping tool, the base is made of steel or a material with similar thermal and / or mechanical properties. This ensures the stability necessary to withstand mechanical loads on the tool.

[0107] When the device is used as an additional component not for clamping tools, the base material may include a metallic material, such as steel, or a thermally insulating material, such as plastic. As described for the device, using a thermally insulating material has the advantage of maximizing the temperature difference between the coolant and the contact elements of the contact portion.

[0108] On the other hand, the present invention relates to a method for cooling tools using a system according to the invention. In the method, coolant is continuously supplied to the inlet of a device for cooling the tool, the volumetric flow rate of the coolant being between 0.01 L / min and 20 L / min, and the coolant circulates completely through the internal channels of the device in a closed loop. Preferably, the coolant is supplied to the inlet of the device at a pressure of up to 10 bar, particularly up to 4 bar.

[0109] Heat dissipation of the tool can be achieved using either uncooled or temperature-controlled coolant. Preferably, a coolant with an arbitrary amount of high specific heat capacity (cp), such as water, for example desalinated water, deionized water, or ultrapure water, is used. To inhibit corrosion, environmentally friendly additives are used in a preferred embodiment of the method. Furthermore, when using coolant temperatures below the freezing point, it is preferable to add other additives or glycols. The mechanical and thermal properties of the coolant mixed with additives are preferably designed to minimize the impact on the water's properties.

[0110] In another preferred embodiment of the invention, the volumetric flow rate of the coolant is from 0.01 L / min to 4 L / min, preferably from 1 L / min to 3 L / min. These flow rates allow for particularly rapid heat removal and, in conjunction with the preferred dimensions of the contact portions, cavities, and flow guiding elements, produce a turbulent effect. Simultaneously, the flow rate is low enough to allow for the use of a particularly economical pump.

[0111] In another preferred embodiment of the invention, the coolant temperature is controlled to -20°C to 35°C, wherein a temperature between 5°C and -10°C, particularly around -5°C, is particularly preferred.

[0112] In another preferred embodiment of the invention, the method for cooling tools using the system according to the invention is combined with flood cooling and / or minimum quantity lubrication (MQL) strategies. This can synergistically enhance cooling.

[0113] Those skilled in the art will recognize that the preferred features and advantages of the device of the present invention also apply to the system and method of the present invention, and vice versa.

[0114] Detailed description

[0115] The invention will now be explained in more detail with reference to examples and accompanying drawings, but is not limited thereto. Attached Figure Description

[0116] Figure 1 A schematic diagram of a processing system for cooling workpieces according to a preferred embodiment of the present invention.

[0117] Figure 2 A cross-sectional view of a device for cooling tools according to a preferred embodiment of the present invention.

[0118] Figure 3 A top view of a device for cooling tools according to another preferred embodiment of the present invention.

[0119] Figure 4A A top view of the contact portion according to a preferred embodiment of the present invention.

[0120] Figure 4B A top view of the contact portion according to another preferred embodiment of the present invention.

[0121] Figure 5A A top view of a device for cooling tools, showing the preferred offset of the position of the contact element relative to the center point.

[0122] Figure 5B A top view of a device for cooling tools, showing the preferred minimum distance between the heat source of the tool and the bottom surface of the contact element.

[0123] Figure 5C A cross-sectional view of a device for cooling tools, showing the preferred offset of the position of the contact element relative to the center point.

[0124] Figure 5D A cross-sectional view of a device for cooling tools shows the preferred minimum distance between the heat source of the tool and the bottom surface of the contact element.

[0125] Figure 6 A schematic diagram of the contact portion of the device according to a preferred embodiment of the present invention.

[0126] Figure 7 A schematic diagram of the contact portion of a device according to another preferred embodiment of the present invention.

[0127] Figure 8 A schematic diagram of the contact portion of a device according to another preferred embodiment of the present invention.

[0128] Figure 9 A schematic diagram of a preferred embodiment of the flow guiding element.

[0129] Figure 10 A schematic diagram of another preferred embodiment of the flow guiding element.

[0130] Figure 11 A schematic diagram of another preferred embodiment of the flow guiding element.

[0131] Figure 12 A schematic diagram of another preferred embodiment of the flow guiding element.

[0132] Figure 13 A schematic diagram of a preferred embodiment of the cavity.

[0133] Figure 14 A schematic diagram of another preferred embodiment of the cavity.

[0134] Figure 15 A schematic diagram of another preferred embodiment of the cavity. Detailed Implementation

[0135] Figure 1 A schematic diagram of a system for processing a workpiece under cooling, according to a preferred embodiment of the present invention, is shown. The diagram illustrates a device 1 and a tool 2 for cooling a tool. Device 1 includes a base 4. The base 4 of device 1 is in direct contact with the tool 2. Internal components of device 1 are not visible in this view. The base 4 includes an inlet and an outlet, and is fluidly connected to a system periphery 3. The tool 2 is disposed on a tool holder 6, and device 1 is configured for clamping fingers to secure the tool 2 and tool holder 6 to a tool holder 5. The tool holder 5 may have an interface associated with the tool holder 6 and / or the tool 2, such as a polygonal tapered shank or a square interface.

[0136] The coolant prepared by the system periphery 3 flows through the device 1 and then returns to the system periphery 3, forming a closed fluid loop for tool cooling.

[0137] Figure 2 The diagram shows the path along feed channel 8 (see reference). Figure 3 (Referring to the reference numeral) is shown in a schematic cross-sectional view through the device 1. The feed channel 8 extends spatially 11 through the base 4 and enters the contact portion 7 at an impact angle 12 of 60°. The contact portion 7 represents a cavity within the device 1 and is positioned directly above the contact element 10, which forms the ground of the contact portion 7. The contact portion 7 is fluidly connected between the inlet and outlet of the base via an internal channel comprising at least one feeder 8 and at least one discharger 9 (not shown, see reference numeral). Figure 3The contact portion 7 is also equipped with a flow guiding element, which locally increases the turbulence and flow velocity of the coolant through the contact portion. In this embodiment, the contact element 10 is a diamond plate with a thickness of 0.5 mm. The contact element 10 transfers heat from the tool 2 to the coolant, ensuring that the temperature difference of the contact element 10 along its longitudinal axis does not exceed 5 K.

[0138] Figure 3 A top view of device 1 with contact portion 7 is shown, illustrating internal components that are not necessarily coplanar. Device 1 includes inlet 14 configured for fluid connection to the system periphery 3. A feeder 8 with a constant diameter (solid line) connects inlet 14 to contact portion 7. Dashed lines indicate an alternative embodiment where feeder 8 has a tapered diameter in the flow direction. Contact portion 7 is located above contact element 10, the width and length of which are slightly larger than contact portion. Contact portion 7 is connected to outlet via discharge device 9. The longitudinal axis and central axis of the feeder and discharge device are shown, indicating the main flow direction of coolant through the substrate 4.

[0139] Figure 4A and 4B Two alternative embodiments are shown where multiple feeders 8 enter the contact portion 7. Figure 4A In this embodiment, the contact portion 7 has a substantially rectangular bottom surface with rounded corners 19. A longitudinal axis 16 extends along the contact portion 7, defining the primary flow direction. The contact portion 7 is supplied with coolant via at least one feeder 8. If only one feeder 8 is used, it is preferably opened at or near one end of the longitudinal axis 16. At least one feeder 8 is shown as a solid line. At least one discharger 9 discharges coolant from the contact portion 7 and is preferably located at or near opposite ends of the longitudinal axis 16. Additional feeders 8 may also be provided between the first feeder 8 and the discharger 9; in this example, three additional feeders are also provided. Figure 4A In this embodiment, all feeders 8 are equidistant along the longitudinal axis 16. That is, the distance 17 between the continuous feeders 8 is uniform. Furthermore, all feeders lead to the contact portion 7 such that their centers 15 are located on the longitudinal axis 16 without lateral offset.

[0140] exist Figure 4B In this embodiment, the first and third feeders 8 and the discharger 9 are arranged along the longitudinal axis 16. The lateral deviation 18 between the center 15 of the second and fourth feeders 8 and the longitudinal axis 16 can be changed.

[0141] Figures 5A-5D The preferred relative dimensions and position of the contact element 10 with respect to the tool 2 are shown. The bottom surface of the contact element 10 is indicated by reference numeral 20 and is exemplarily rectangular. The cooling area 21 on the entire tool surface 22 is as follows: Figure 5BAs shown by the dashed lines, the bottom surface 20 of the contact element 10 covers 10% to 100% of the area 21 to be cooled, as indicated by the figure. To improve cooling performance, the contact element 10 may extend along the area 21 for cooling at the cutting edge of the tool 2. This may require moving the position of the contact element 10 from the depicted rectangle 20 to one end of the area 21 to be cooled, indicated by reference numeral 23. It is possible for the protrusion of the device 1 to extend beyond the corresponding area 21 of the tool 22 to be cooled, but this results in reduced cooling performance.

[0142] Figures 5A-5D The distance 24 between the contact element 20 and the contact area 25 of the tool's cutting surface is shown. The contact area 25 can be considered a heat source. Preferably, the distance 24 is kept as small as possible to achieve optimal heat transfer from the cutting surface to the coolant. The displacement 23 of the contact element 20 enables this. Furthermore, the distance 24 between the contact element 20 and the heat source 25 should not exceed half the distance between the two symmetrically opposite edges of the tool 2. When reducing the distance 24, negative impacts on cut material discharge should generally be avoided.

[0143] Figure 6 A cross-sectional view of the longitudinal axis 16 of the contact portion 7 according to a preferred embodiment of the present invention is shown. The impinging flow of coolant from the feeder 8 to the contact element 10 is indicated by reference numeral 26. This impingement occurs in a plane perpendicular to the observation plane, with an impact angle 12 of 90° relative to the ground surface 31 of the contact portion 7. This maximum impact angle 12 generates high heat flux based on turbulence effects. Furthermore, selecting such a large impact angle can reduce the velocity of the same turbulent flow, thereby improving the solution efficiency.

[0144] Due to the temperature difference between the coolant and the contact element 10 at the ground surface 31, a thermal boundary layer is formed along the ground surface 31. The resulting temperature gradient and boundary layer thickness affect heat transfer to the coolant. In this embodiment, the ground surface 31 is the surface of the contact element 10. The cooling performance depends on the temperature difference of the contact element 10 along the flow axis in the contact portion 7, and is less than 5K. To further reduce the temperature difference, multiple feeders 8 supply temperature-controlled coolant along the entire contact portion 7.

[0145] Cavities 27 are provided between the continuous feeders 8 and between the last feeder 8 and the discharger 9. These locally enlarge the cross-section of the contact portion 7 and are defined by the break edge 32. Geometrically shaped flow guide elements 28 are also located on the bottom surface 31 of the contact portion 7 before or between the feeders 8. By integrating the cavities 27 with the flow guide elements 28, forced flow deformation occurs due to the separation effect 29 and vortex formation 30. The impinging flow 26 of the feeders 8, the inclined surface of the flow guide elements 28, and the break edge 32 guide the coolant toward the bottom surface 31 to achieve high heat transfer from the contact element 10. The impinging flow region 51 on the bottom surface is highlighted with a dashed line.

[0146] Figure 7 Possible variations of the break edge 32 of cavity 27 are shown. The primary flow direction extends from right to left along contact portion 7. Solid lines represent the 90° external angle of the break edge 32 relative to the inner wall of contact portion 7 in the upward direction (the first three break edges 32 on the right). Coolant impacts these edges, creating eddies in cavity 27. Variations in flow behavior can be achieved by changing the external angle, for example, by moving the tip 34 of the break edge 32 (indicated by the left-pointing arrow). This also changes the downward obtuse angle 33 of the break edge 32. These variations can be combined with the positioning and tilting of the inclined surface of the flow guide element 28 to guide coolant to bottom surface 31. Reference numeral 35 indicates possible adjustments to the diameter of feeder 8, for example, by adjusting it to a conical shape so that feeder 8 functions as a high-speed nozzle to spray coolant into contact portion 7.

[0147] Figure 8 The parameters of cavity 27, which can be adjusted to modify the flow pattern, are shown. For example, the distance 36 between the continuous tips 34 of the broken edge can be varied to manipulate vortex formation near the bottom surface 31. Furthermore, the height or depth 37 of cavity 27 can be adjusted to generate vortices with larger radii.

[0148] Figure 9 A schematic diagram of a preferred embodiment of the flow guiding element 28 for generating the impinging flow 26 is shown. The feeder 8 guides the impinging flow 26 onto the contact element 10. The flow guiding element 28 is used to control the interaction between the flow along the flow path 7 and the feeder 8. These elements cause flow separation, thereby creating turbulence. In this embodiment, the flow guiding element 28 is located in the cavity 27, the cross-section of which is preferably described by an isosceles triangle with an interior angle 38 having a maximum of 60°. By increasing the radian 37, the separation effect can be altered, enhancing the turbulence. In another preferred embodiment, the interior angle 38 of the flow guiding element 28 ranges from 5° to 60°, altering the flow path in the feeder 8 and the separated flow 29.

[0149] Figure 10 Preferred embodiments of the flow guiding element 28 at different locations are shown. Preferably, the flow guiding element 28 is disposed along the flow channel between the feeder 8 and the outlet edge 32 of the cavity, with one side of the element 28 located at the bottom of the flow channel 31. By reducing the distance 41 between the flow guiding element 28 and the outlet edge 32, the resulting flow velocity is increased, thereby changing the position of the separated flow 29 of the coolant.

[0150] Figure 11 Preferred embodiments of flow guiding elements 28 with different heights 42 and widths 43 are shown to achieve desired flow rates. The height 42 may be reduced or the width 43 may be increased. Preferably, the angle 38 of the edge required for separating the flow 29 is not less than 5°. The aspect ratio of height 42 to width 43 is preferably between 1:10 and 3:1.

[0151] Figure 12 A preferred embodiment of the flow guiding element 28 is shown. Preferably, the flow guiding element 28 is arranged collinearly with the contact element 10, located on or parallel to the longitudinal axis 11 of the feeder 8. In another embodiment, the flow guiding element 28 is located away from the contact element 10, forming a gap 44. This results in a secondary flow 45, increasing the flow velocity and turbulence in this region.

[0152] Figure 13 A preferred embodiment of cavity 27 for generating targeted backflow and increasing turbulence in the flow channel on the side of contact element 10 is shown. An angle 46 of 5°–60° is applied to the top 47 of the cavity. In another preferred embodiment, an arc is applied at the cavity corner 48 to enhance turbulence. A flow guiding element 28 is preferably disposed inside cavity 27, having a vertical distance 49 from the bottom of flow channel 31 / contact element 10. The flow guiding element 28 does not contact the cavity edge and is free within the flow channel. A preferred range is 20% to 40% of the vertical distance 49. The lower edge of the flow guiding element 28 is preferably upstream of the first outlet edge 32. This causes flow separation above and below element 28 along the flow channel. Turbulent eddies with backflow are formed above element 28, increasing turbulence at the bottom of flow channel 31.

[0153] Figure 14 A preferred embodiment of the cascaded cavities 27 is shown. Cavities 27 have both an angle 46 and an arc 48, producing a repeatable flow pattern and generating turbulence along the flow channel 7 from the feeder 8 to the discharger 9.

[0154] Figure 15 A preferred embodiment of cavity 27 and flow guiding element 28 is shown. The distance 50 from the center of flow guiding element 28 to the first outlet edge 32 is greater than 0 mm, allowing the formation of turbulent eddies with backflow in the upper fluid flow, thereby increasing turbulence below element 28. Increasing the vertical dimension of element 28 and decreasing the vertical distance 49 between element 28 and outlet edge 32 reduces the cross-section of flow channel 7, increasing turbulence at the bottom. The corner radius allows flow separation within cavity 27.

[0155] Reference Marker

[0156] 1 Equipment for cooling tools

[0157] 2 tools

[0158] 3. System peripheral equipment

[0159] 4 matrix

[0160] 5 Tool Holders

[0161] 6 tool holders

[0162] 7 Contact parts

[0163] 8 feed channels

[0164] 9 discharge channels

[0165] 10 contact elements

[0166] 11 Spatial orientation of the feeding or discharging channel

[0167] Impact angle between the 12-channel axis and the bottom surface of the contact portion

[0168] 13. Thickness of contact element

[0169] 14. Entrance or Exit

[0170] 15. Cross-section of the feed channel or discharge channel

[0171] 16. Vertical axis of the contact portion

[0172] 17. Distance between the central axes of the feed channels

[0173] 18. Distance between the central axis of the feed channel and the longitudinal axis of the contact portion

[0174] 19. Edges of contact portions with rounded corners

[0175] 20. Bottom surface of contact element

[0176] 21. Cooling area of ​​tool

[0177] 22 tool plate shape

[0178] 23. Distance between the center point of the tool and the preferred center point of the contact element

[0179] 24. Distance between the contact element and the tool heat source, especially the contact area of ​​the tool's cutting edge.

[0180] 25. Contact area of ​​the cutting edge of the tool

[0181] 26 Feed channel coolant flow

[0182] 27 chambers

[0183] 28 Flow guiding element (StrömungcositElement) / Geometry

[0184] 29. Flow separation (disconnection point)

[0185] 30 Vortex Formation

[0186] 31. The lower side / bottom surface of the contact part

[0187] 32-cavity vibration or disconnection edge

[0188] 33. Disconnect the edge to the outer angle (obtuse angle) of the cavity.

[0189] 34. Displacement of the tip of the disconnected edge from the orthogonal position towards the feed channel

[0190] 35. Diameter of the feed or discharge channel

[0191] 36-cavity width

[0192] 37. Height (or depth) of the cavity

[0193] 38. The inner angle of the flow guiding element relative to the inner wall of the contact portion

[0194] 39. By changing the inner angle with the inner wall of the contact portion, the tip of the flow guiding element is displaced.

[0195] 40 Position of the flow guiding element

[0196] 41. Upstream distance between the tip of the flow guiding element and the tip of the nearest cavity's break edge

[0197] 42. Reduced height of the flow guiding element

[0198] 43. Width-enhanced flow guiding element

[0199] 44. Gap between exposed flow guiding elements and contact elements

[0200] 45. Secondary flow of coolant through the gap

[0201] The angle between the inclined inner wall of cavity 46 and the inner wall of the contact portion

[0202] The inner wall of cavity 47

[0203] 48 cavity inner corner

[0204] Distance between the exposed flow guiding element and the contact element in cavity 49

[0205] The upstream distance between the exposed flow guiding element in the 50 cavity and the nearest disconnection edge

[0206] Impact flow in the direction of the bottom surface (region) 51

Claims

1. Equipment for cooling tools (2), The device includes a base (4), a contact element (10), at least one inlet for entering the base (4), and an outlet for leaving the base (4), the inlet and the outlet being connected to each other through one or more internal channels in the base (4); The device can be connected to the tool (2) so that the contact element (10) contacts the tool (2); and The one or more internal channels are used for coolant conduction; Its features are, The one or more internal channels include a contact portion (7) that contacts the contact element (10), and the contact portion (7) includes a plurality of flow guiding elements (28) for locally increasing the turbulence and flow rate of the coolant passing through the contact portion (7).

2. The device according to claim 1, Its features are, The contact element (10) forms the inner wall of the contact portion (7); One or more flow guiding elements (28) are also preferably in contact with the contact element (10), permanently connected to the contact element (10) or forming part of the contact element (10), and used for heat conduction from the contact element (10) to the coolant.

3. The device according to any one of the preceding claims, Its features are, The flow guiding element (28) protrudes from the inner wall of the contact portion (7), particularly from the bottom surface or from the contact element (10), and forms a local contraction in the cross section of the contact portion (7), wherein preferably, at least one surface of the flow guiding element (28) forms an exterior angle of 90° to 175° with the inner wall of the contact portion (7), particularly an exterior angle of 100° to 150°.

4. The device according to any one of the preceding claims, Its features are, At least one flow guiding element (28) is connected to two parallel inner walls of the contact portion (7) and is separate from the other inner walls of the contact portion (7), wherein the two parallel inner walls are substantially orthogonal to the contact element (10).

5. The device according to any one of the preceding claims, Its features are, One or more inner walls of the contact portion (7) have cavities (27), the cavities (27) being represented as a partial enlargement of the cross section of the contact portion (7), wherein the cavities (27) are preferably defined by a break edge (29), the break edge (29) preferably forming an external angle of 90° to 175° with the corresponding inner wall.

6. The device according to any one of the preceding claims, Its features are, The flow guiding element (28) has a prism shape, pyramid shape, polyhedral shape, spherical shape or ellipsoidal shape or a combination thereof, wherein a prism shape with an isosceles triangular cross section and a rounded tip is preferred; The ratio of the height to the width of the flow guiding element (28) is preferably between 1:10 and 3:

1.

7. The device according to any one of the preceding claims, Its features are, The contact element (10) has a thermal conductivity of at least 100 W / m. -1 K -1 And the composition of materials with a melting point greater than 600°C, The material is preferably selected from diamond, copper, gold, silver, aluminum, or an alloy of copper, gold, silver, or aluminum.

8. The device according to any one of the preceding claims, Its features are, The surface roughness of the contact element (10) facing the contact portion (7) is 0.1µm-200µm, particularly 25µm-50µm, and the surface roughness of the contact element (10) facing the tool (2) is less than 0.1µm.

9. The device according to any one of the preceding claims, Its features are, The one or more internal channels 1-15, especially internal channels 3-8, include a feeder (8) and one or more dischargers (9). The feeder (8) is located in the feed plane above the discharge plane occupied by the contact portion (7) and / or the discharger (9).

10. The device according to the preceding claims, Its features are, The feeder (8) leads to the contact portion (7), wherein the flow direction of the feeder (8) is preferably set to be 0°-90°, especially 30°-60°, with respect to the surface of the contact element (10) facing the tool (2).

11. The device according to any one of the preceding claims, Its features are, The contact portion (7) has a longitudinal axis, and the one or more internal channels include a plurality of feeders (8), wherein the first feed channel extends to the contact portion (7) at a lateral distance (18) different from the longitudinal axis (16) of the contact portion (7) compared to the second feed channel.

12. The device according to any one of the preceding claims, Its features are, The flow element locally reduces the cross-section of the contact portion (7) by at least 20%, particularly at least 30%, wherein the cross-section of the contact portion (7) is preferably 0.008 mm. 2 Up to 20mm 2 Between, especially at 0.2mm 2 Up to 3.5mm 2 between.

13. A system for processing workpieces under cooling conditions. Its features are, The system includes a device for cooling a tool (2) according to any one of the preceding claims, the tool (2), and means for connecting the device to the tool (2); The system also includes a fluid circuit for delivering coolant to the inlet and delivering the coolant from the outlet of the device for cooling the tool (2).

14. The system according to the preceding claims, Its features are, The device for cooling the tool (2) is used as a clamping finger for holding the tool (2) or as a cooling unit, wherein the base (4) of the device preferably comprises a metallic material.

15. A method using the system for cooling tools (2) according to claim 13 or 14, Its features are, At 0.01 l min -1 Up to 20 l min -1 The volumetric flow rate continuously guides the coolant into the inlet of the device for cooling the tool (2), wherein the coolant circulates in a closed loop including the internal channels of the device.

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