Clamping mandrel adapter device, assembly method for assembling a clamping mandrel adapter device, and machine tool system with a machine tool and with a clamping mandrel adapter device
Patent Information
- Application Number
- EP2023710751
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-04-12
- Filing Date
- 2023-03-10
- Publication Date
- 2025-02-19
AI Technical Summary
Existing mandrel adapter devices for mounting hole saw units on machine tools lack efficient centering and quick tool change capabilities, leading to vibration issues and reduced cutting quality.
A mandrel adapter device with a one-piece adapter base body featuring a hexagonal tool interface and a hollow cylindrical tool holder, incorporating a quick-clamping unit for centering drills and a rotary clamping unit for hole saws, allowing for secure torque transmission and tool-free assembly/disassembly.
The solution provides improved centering, reduced vibration, extended service life, high cutting quality, and quick tool changes, ensuring precise and robust operation of the hole saw unit.
Smart Images
Figure 1.1
Abstract
Description
[0001] Description
[0002] Clamping mandrel adapter device, assembly method for assembling a clamping mandrel adapter device, and machine tool system with a machine tool and a clamping mandrel adapter device
[0003] State of the art
[0004] A mandrel adapter device for mounting a hole saw unit, which comprises at least one center drill and a hole saw, on a machine tool, with at least one adapter base body, which comprises at least one tool interface for mounting on the machine tool and at least one tool holder for receiving the hole saw unit, has already been proposed.
[0005] Disclosure of the invention
[0006] The invention is based on a mandrel adapter device for mounting a hole saw unit, which comprises at least one center drill and a hole saw, on a machine tool, with at least one adapter base body, which comprises at least one tool interface for mounting on the machine tool and at least one tool holder for receiving the hole saw unit.
[0007] It is proposed that the mandrel adapter device comprises at least one, in particular circular-cylindrical, receiving area for the center drill and one, in particular hollow-cylindrical, receiving area for the hole saw, wherein the tool holder is designed as a hollow cylinder with an inner circumferential surface and an outer circumferential surface and delimits the at least one, in particular circular-cylindrical, receiving area for the center drill with the inner circumferential surface and at least partially delimits the, in particular hollow-cylindrical, receiving area for the hole saw with the outer circumferential surface, wherein the tool holder, in particular the entire adapter base body, is designed as a single piece.
[0008] In this context, a mandrel adapter device should be understood to mean, in particular, an adapter which is intended to connect the hole saw unit to the machine tool in order to transmit at least a torque from the machine tool to the hole saw unit. The mandrel adapter device is designed such that the hole saw unit can be assembled and disassembled non-destructively and without tools. The mandrel adapter device is intended for non-destructive assembly and disassembly on the machine tool. The mandrel adapter device is designed such that the tool interface and the tool holder have the same axis of rotation. In this context, a hole saw should be understood to mean, in particular, a circular-cylindrical cutting tool. The hole saw is, in particular, at least substantially hollow-cylindrical and delimits a cylindrical space.The hole saw is intended for producing a circular bore. When the hole saw unit is assembled, the center drill is preferably arranged at least partially within the space defined by the hole saw. The center drill preferably extends through the space defined by the hole saw. When the hole saw unit is assembled, the center drill and the hole saw preferably have a common axis of rotation. The hole saw unit is intended for use on the machine tool. The machine tool is preferably designed as a drilling machine, in particular a pillar drill, a hand drill, or another machine tool deemed appropriate by a person skilled in the art, by means of which the mandrel adapter device can be driven in rotation. The adapter base body is preferably intended to accommodate the hole saw unit and connect it to the machine tool.The adapter base body is preferably provided to transmit a rotational movement of the machine tool to the hole saw unit. The adapter base body preferably forms the tool interface for a connection to a tool holder of the machine tool. The tool interface is preferably polygonal. The tool interface is preferably hexagonal. Alternatively, it is conceivable for the tool interface to be circular-cylindrical, conical, or polynomial. In a circular-cylindrical design, the tool interface preferably has at least one recess for assembly and disassembly. The fact that the tool interface is polygonal, in particular hexagonal, should be understood to mean in particular that at least one cross-sectional area of the tool interface is polygonal, in particular hexagonal.The tool interface preferably has a polygonal, in particular hexagonal, cross-sectional area over at least 50%, preferably at least 75%, and particularly preferably at least 95%, of its total extent in a main extension direction of the tool interface. A "main extension direction" of an object should be understood in particular as a direction that runs parallel to a longest edge of a smallest geometric cuboid that just completely encloses the object. The tool interface is preferably intended to be received by the machine tool. The tool interface is preferably made of solid material. In a hexagonal design, the tool interface preferably has a groove that completely surrounds the tool interface.The groove of the tool interface is preferably provided for a quick-change system between the mandrel adapter device and the machine tool. Preferably, the groove is formed in particular by a recess for a ball detent. Preferably, the tool interface is formed by a, in particular standardized, HEX interface. Preferably, a torque provided for driving the hole saw unit is transmitted from the machine tool to the adapter base body by means of a positive connection, in particular through the hexagonal cross-section of the tool interface. The receiving area for the center drill preferably has at least one opening for inserting the center drill. The opening for the center drill is preferably arranged on a side of the adapter base body facing away from the tool interface.The tool holder is preferably designed such that the hole saw and the center drill have the same axis of rotation. Preferably, the tool holder and the tool interface are integrally connected. Advantageously, "integral" should also be understood as "one-piece." "One-piece" should be understood in particular as "molded in one piece." This one piece is preferably produced from a single blank, a mass, and / or a cast, particularly preferably using an injection molding process, in particular a single-component and / or multi-component injection molding process.
[0009] The inventive design of the mandrel adapter device advantageously provides a tool holder for a hole saw and a center drill with improved centering properties. Vibration of the mandrel adapter device can be advantageously kept low. An advantageously long service life of the mandrel adapter device can be achieved. A high cutting quality can be advantageously provided during operation of the mandrel adapter device. A mandrel adapter device with advantageously fast tool changes can be provided.
[0010] It is further proposed that the mandrel adapter device have a quick-clamping unit with at least one quick-clamping element which is arranged in a bore in the adapter base body, wherein the quick-clamping unit is provided for fixing and releasing the center drill at least axially in the receiving area of the center drill. Preferably, the quick-clamping element forms a thread for screwing into the adapter base body. Preferably, the adapter base body has the bore with a thread for screwing in the quick-clamping element. The quick-clamping element is preferably designed as a screw, in particular a grub screw. The quick-clamping element preferably has a clamping surface which is provided at least for fixing the center drill at least partially in the receiving area of the center drill when the quick-clamping element is screwed in.The center drill is preferably axially fixed in the receiving area by means of a force-locking connection. The force-locking connection preferably exists between the clamping surface of the quick-clamping element and the center drill, in particular a flat surface of a shank of the center drill. Preferably, the quick-clamping element is provided at least to transmit the torque of the machine tool to the center drill. Preferably, the torque of the machine tool is transmitted from the adapter base body to the center drill by means of the quick-clamping element. The torque is preferably transmitted by means of a positive connection between the quick-clamping element and the center drill. Preferably, the quick-clamping unit has a locking element which is provided to axially fix the center drill in the receiving area.The locking element is preferably provided to axially fix the center drill in the receiving area by means of a positive connection. The quick-clamping unit preferably has a spring which is provided to press the locking element radially against the center drill. The spring and the locking element are preferably arranged in an opening which is delimited by the quick-clamping element. The locking element is preferably designed as a ball. However, other configurations for the locking element which appear appropriate to a person skilled in the art are also conceivable, which enable the center drill to be axially fixed in the receiving space of the center drill by means of a positive connection.Preferably, the positive connection between the locking element and the center drill is created via the locking element and a recess, in particular a locking groove, arranged in the center drill, in particular in the flat surface of the shank of the center drill. Preferably, the center drill is axially fixed by means of the frictional connection between the clamping surface of the quick-action clamping element and the center drill and / or by means of the positive connection between the fixing element and the center drill. It is conceivable for the center drill to be axially fixed only by means of the positive connection using the locking element, by screwing the quick-action clamping element into the adapter base body until the locking element is arranged in the locking groove of the center drill, but the clamping surface is free from contact with the center drill when the machine tool is not in operation.However, it is also conceivable for the quick-clamping element to be connected to the adapter base body by means of a joint. The joint is preferably designed as a press-fit, adhesive-fit, or welded connection. The design of the mandrel adapter device advantageously allows a center drill that is free of a hexagonal cross-sectional area to be fastened axially and for torque transmission in a receiving area for the center drill. A mandrel adapter device with a system for quickly changing the center drill can advantageously be provided. A circular-cylindrical center drill with at least one flat surface, with or without a locking groove, can advantageously be driven in a precisely centered manner. An advantageously low radial guide play can be achieved by a particularly long cylindrical guide for the center drill by means of a receiving area for the center drill.Advantageously, axial and radial guide play can be eliminated by tightening the quick-clamping element, in particular by means of the force-locking connection between the quick-clamping element and the center drill. Furthermore, it is proposed that the mandrel adapter device have at least one rotary clamping unit, which is provided for axially fixing and releasing the hole saw, wherein the rotary clamping unit comprises at least one bushing, which is connected, in particular integrally, to the adapter base body and completely encloses at least a part of the hole saw received in the receiving area, and at least one sleeve rotatably mounted on the bushing, which is provided for enabling the fixing and release of the hole saw by means of rotation, wherein the bushing is arranged between the sleeve and the adapter base body.The bushing is preferably connected to the adapter base body by means of a material bonding process, in particular a laser welding process. It is conceivable for the bushing to be connected to the adapter base body by means of another process that appears appropriate to a person skilled in the art and is suitable for connecting the bushing, in particular in one piece, to the adapter base body, for example by means of an adhesive process and / or a welding process. It is also conceivable for the bushing to be screwed onto the adapter base body by means of a thread and / or attached by means of a shrink connection. The bushing preferably has a smaller maximum longitudinal extent than the receiving area of the center drill. The bushing preferably completely encloses the tool holder in at least one plane perpendicular to the longitudinal extent of the tool holder.Preferably, the bushing and the outer surface of the tool holder form the receiving area for the hole saw. Preferably, the bushing is designed as a hollow cylinder and has an inner bushing surface and an outer bushing surface. Preferably, the receiving area for the hole saw is delimited by the outer surface of the tool holder and the inner bushing surface. Preferably, the bushing delimits a space which has a hexagonal cross-sectional area. The bushing is preferably provided to transmit the torque from the machine tool via the adapter base body to the hole saw. Preferably, the bushing transmits the torque of the machine tool by means of a positive connection between the bushing and the hole saw. The positive connection between the bushing and the hole saw is preferably created by the hexagonal design of the cross-sectional area of the space delimited by the bushing.The sleeve preferably has a smaller maximum longitudinal extent than the bushing. The sleeve is preferably hollow-cylindrical. The bushing preferably extends completely through the sleeve. The term "the bushing extends completely through the sleeve" should be understood to mean that the bushing extends from a first opening in the hollow-cylindrical sleeve through the sleeve to a second opening in the hollow-cylindrical sleeve. The sleeve preferably has the same axis of rotation as the hole saw and / or the center drill. The design of the mandrel adapter device allows for advantageously precise centering of the hole saw. A robust mandrel adapter device can advantageously be provided.
[0011] It is further proposed that the rotary clamping unit for fixing and releasing the hole saw has at least one fixing element, in particular two fixing elements, which fix(s) or release(s) the hole saw depending on one of at least two rotational positions of the sleeve. Preferably, the bushing defines an opening for each fixing element, which opening is provided for guiding the fixing elements in a radial direction into or out of the receiving space of the hole saw. Preferably, the sleeve defines a cutout for each fixing element. The at least one cutout is preferably provided for at least partially accommodating the at least one fixing element, which is guided radially out of the receiving space of the hole saw. Preferably, the at least one fixing element is designed as a sphere. The rotary clamping unit preferably has the two rotational positions for the sleeve.Preferably, a first of the two rotational positions, a fixing position, is provided for fixing the hole saw. Preferably, a second of the two rotational positions, a release position, is provided for releasing the hole saw. Preferably, the sleeve is provided at least to press the at least one fixing element radially into the receiving space of the hole saw in the fixing position. The sleeve is provided at least to provide the at least one fixing element, in the release position, with the possibility of retraction from the receiving space of the hole saw by means of the at least one cutout. Preferably, the rotary clamping unit has at least one positioning element. Preferably, the positioning element is designed as a pin. Preferably, the bushing delimits at least one plug-in opening. Preferably, the plug-in opening is provided to at least partially receive the positioning element. Preferably, the sleeve has a positioning groove.The positioning element is preferably intended to be arranged at least partially in the positioning groove of the sleeve when the rotary clamping unit is in the assembled state. The positioning groove is preferably intended to guide the positioning element when the sleeve is rotated between the two rotational positions. The positioning groove is preferably delimited in a longitudinal direction by two walls of the sleeve. The two walls are preferably intended to form the two rotational positions of the rotary clamping unit. The positioning element is preferably arranged in the positioning groove in such a way that the sleeve is guided from one rotational position to the other when rotated between the two walls of the positioning groove. The angle of rotation between the two rotational positions is preferably between 20° and 60° and particularly preferably 40°.The design of the mandrel adapter device allows for a robust, structurally simple, and minimally complicated fixing and release system for a hole saw. It also allows for an advantageously easy-to-use system for tool-free fixing and releasing of a hole saw.
[0012] Furthermore, it is proposed that the rotary clamping unit has at least one return spring, which is intended to hold / reset the sleeve in one of the two fixed positions of the rotation. The return spring is preferably designed as a torsion spring. The return spring preferably has two legs, each extending parallel to a rotation axis of the torsion spring. The two legs preferably extend in opposite directions. Preferably, one of the two legs is arranged in a spring leg holder delimited by the bushing when the rotary clamping unit is in the assembled state. Preferably, a second of the two legs is arranged in a further spring leg holder delimited by the sleeve when the rotary clamping unit is in the assembled state. The return spring preferably encloses the bushing.The return spring is preferably provided to absorb and store at least a portion of the torque applied when rotating the sleeve. In particular, the sleeve stores the torque applied to rotate the sleeve from the fixing position to the release position. The return spring is preferably provided to return the sleeve from the release position to the fixing position using the stored torque and to hold it in the release position using a spring force of the return spring. The return spring is preferably preloaded to hold the sleeve in the fixing position. The rotary clamping unit is preferably designed such that the sleeve is rotated in one direction of rotation from the fixing position to the release position in order to release the hole saw.The direction of rotation for releasing the hole saw is preferably clockwise, viewed from the tool interface to the tool holder. The design of the mandrel adapter device provides an advantageously secure mount for a hole saw. Accidental release of the hole saw can be advantageously prevented. Because the direction of rotation of the sleeve for release is clockwise, accidental release of the hole saw during operation, in which the direction of rotation is usually clockwise, is advantageously prevented.
[0013] It is further proposed that the rotary clamping unit has at least one locking ring and at least one further return spring, wherein the further return spring is provided to press the at least one fixing element, in particular the two fixing elements, at least to a large extent out of the receiving area, in particular in the radial direction, by means of the locking ring. The further return spring is preferably designed as a compression spring. The further return spring is preferably arranged in the receiving space of the hole saw. The further return spring is preferably arranged after the locking ring in an insertion direction of the hole saw. The locking ring is preferably provided at least to transfer an insertion force from the hole saw to the further return spring when inserting the hole saw.The insertion force is preferably applied to press the hole saw into the receiving space of the further hole saw against a spring force of the further return spring. Preferably, the further return spring is provided to store at least part of the insertion force. The further return spring is provided to use the stored insertion force to press the at least one fixing element, in particular the two fixing elements, out of the receiving space of the hole saw by means of the locking ring. The locking ring is preferably arranged completely in the receiving space of the hole saw. Preferably, the locking ring and the further return spring enclose the adapter base body. The locking ring is preferably designed as an elastic snap ring. The locking ring preferably has retaining arms. The retaining arms extend inside the locking ring in the direction of a rotation axis of the locking ring.The holding arms preferably each have a radially inwardly extending shoulder. The locking ring is preferably made of spring steel sheet or of machined spring steel. The sleeve is preferably fixed in the release position by the at least one fixing element, in particular the two fixing elements, being pushed radially out of the receiving space of the hole saw, in particular when the receiving space of the hole saw is free of the hole saw. The tool holder preferably has at least one region with a reduced outer diameter. The region with the reduced outer diameter is preferably provided for securing the locking ring by means of the holding arms. Due to the design of the mandrel adapter device, a hole saw can advantageously be picked up and released from the tool holder in a simple and user-friendly manner.
[0014] Furthermore, it is proposed that the bushing have a radially outward-projecting, circumferentially extending protective shoulder which is arranged on a side of the adapter base body facing away from the tool interface and is intended to protect the sleeve in the axial direction from external influences, in particular during operation of a machine tool. Preferably, the spring leg holder delimited by the bushing is arranged in the protective shoulder of the bushing. The design of the mandrel adapter device advantageously protects the sleeve from external influences from the axial direction. Unintentional release of the hole saw can advantageously be prevented. The mandrel adapter can advantageously be protected from external influences from the axial direction. An advantageously simple and cost-effective mandrel adapter device with sufficient protection can be provided.
[0015] Furthermore, an assembly method for assembling the mandrel adapter device is proposed. In one method step, the further return spring is pushed onto the adapter base body into the receiving space of the hole saw. Preferably, in one method step, the locking ring is pushed onto the adapter base body into the receiving space of the hole saw. The locking ring is preferably pushed onto the adapter base body after the further return spring. Preferably, when the locking ring is pushed on, the holding arms elastically deform radially outwards to enable sliding on. Preferably, the locking ring is pushed into the receiving area of the hole saw until it is arranged in the area of the tool holder with the reduced outer diameter. Preferably, the holding arms spring back elastically to their original shape once they have reached the area with the reduced outer diameter.In this context, the "initial shape of the retaining arms" refers, in particular, to a stress-free state of the locking ring, in particular of the retaining arms. The inventive design of the assembly method allows a mandrel adapter device to be assembled advantageously cost-effectively and without the need for additional work steps or work parts.
[0016] Furthermore, a machine tool system comprising a machine tool and the mandrel adapter device is proposed. The machine tool is preferably designed as a drilling machine or a hand-held drill. In particular, the machine tool can have a housing, a handle, a power supply unit, such as an accumulator, a battery, a mains power supply, or the like, a drive unit, an output unit, and / or other components deemed appropriate by a person skilled in the art. Advantageously, a user-friendly and user-safe mandrel adapter device can be provided.
[0017] The chip mandrel adapter device according to the invention, the assembly method according to the invention for assembling the mandrel adapter device, and the machine tool according to the invention with the mandrel adapter device are not intended to be limited to the application and embodiment described above. In particular, the chip mandrel adapter device according to the invention, the assembly method according to the invention for assembling the mandrel adapter device, and the machine tool according to the invention with the mandrel adapter device can have a number of individual elements, components, units, and method steps that differs from the number stated herein in order to fulfill a function described herein. Furthermore, in the value ranges specified in this disclosure, values within the stated limits are also to be considered disclosed and can be used as desired.
[0018] drawing
[0019] Further advantages will become apparent from the following description of the drawings. The drawings illustrate an exemplary embodiment of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.
[0020] They show:
[0021] Fig. 1 shows a machine tool system according to the invention with a machine tool and a mandrel adapter device according to the invention in a schematic representation, Fig. 2 shows the mandrel adapter device with a center drill and a hole saw in a schematic sectional representation, Fig. 3 shows part of the mandrel adapter device according to the invention in a schematic sectional representation,
[0022] Fig. 4 shows the mandrel adapter device according to the invention with a rotary clamping unit in a release position in a schematic sectional view,
[0023] Fig. 5 shows the mandrel adapter device according to the invention with a rotary clamping unit in a fixing position in a schematic sectional view,
[0024] Fig. 6 the mandrel adapter device according to the invention in a schematic exploded view,
[0025] Fig. 7 shows a part of the mandrel adapter device according to the invention in a schematic representation,
[0026] Fig. 8 shows a part of the mandrel adapter device according to the invention in a schematic sectional view and
[0027] Fig. 9 shows an assembly method according to the invention in a schematic representation
[0028] Description of the embodiment
[0029] Figure 1 shows a machine tool system comprising a machine tool 10 and a mandrel adapter device 12. The machine tool 10 is designed as a hand-held drill. The machine tool 10 has a housing, a handle, a power supply unit, in particular a battery, and a drive unit.
[0030] Figure 2 shows the mandrel adapter device 12 for mounting a hole saw unit 14, which comprises at least one center drill 16 and a hole saw 18, on the machine tool 10. The mandrel adapter device 12 has an adapter base body 20, which comprises a hexagonal tool interface 22 for mounting on the machine tool 10 and a tool holder 24 for receiving the hole saw unit 14. The mandrel adapter device 12 has a circular-cylindrical receiving area 26 for the center drill 16 and a hollow-cylindrical receiving area 28 for the hole saw 18. The tool holder 24 is hollow-cylindrical with an inner circumferential surface 30 and an outer circumferential surface 32. The tool holder 24 partially delimits the one circular cylindrical receiving area 26 for the center drill 16 with the inner circumferential surface 30, as well as the hollow cylindrical receiving area 28 for the hole saw 18 with the outer circumferential surface 32.When the hole saw unit 14 is assembled, the center drill 16 is arranged in a space defined by the hole saw 18. The adapter base body 20 is provided to receive the hole saw unit 14 and connect it to the machine tool 10. The adapter base body 20 is provided to transmit a rotational movement of the machine tool 10 to the hole saw unit 14. The adapter base body 20 forms the tool interface 22 and the tool holder 24. The tool interface 22 is provided to be received by the machine tool 10. The tool interface 22 is made of solid material. The tool interface 22 has a groove 56 that completely surrounds the tool interface 22. The groove 56 of the tool interface 22 is provided for a quick-change system between the mandrel adapter device 12 and the machine tool 10.A torque, which is provided for driving the hole saw unit 14, is transmitted from the machine tool 10 to the adapter base body 20 by means of a positive connection through the hexagonal cross-section of the tool interface 22. The receiving area 26 for the center drill 16 has an opening 42 for inserting the center drill 16. The opening 42 for the center drill 16 is arranged on a side of the adapter base body 20 facing away from the tool interface 22. The tool holder 24 is designed such that the hole saw 18 and the center drill 16 have the same axis of rotation in the assembled state. The tool holder 24, in particular the entire adapter base body 20, is formed in one piece. The tool holder 24 and the tool interface 22 are connected to one another in one piece.
[0031] The mandrel adapter device 12 has a quick-clamping unit 34 with at least one quick-clamping element 36. The quick-clamping element 36 forms a thread for screwing into the adapter base body 20, wherein the quick-clamping unit 34 is provided to fix and release the center drill 16 at least axially in the receiving area 26 of the center drill 16. The adapter base body 20 has a bore 60 with a thread for screwing in the quick-clamping element 36. The bore 60 leads from an outside of the adapter base body into the receiving area 26 for the center drill 16. The quick-clamping element 36 is designed as a screw. The quick-clamping element 36 has a clamping surface 62, which is provided to fix the center drill 16 axially in the receiving area 26 of the center drill 16 when the quick-clamping element 36 is screwed in.The center drill 16 is axially fixed in the receiving area 26 by means of a force-locking connection. The force-locking connection exists between the clamping surface 62 of the quick-clamping element 36 and the center drill 16, in particular a flat surface 64 of a shank of the center drill 16. The quick-clamping element 36 is provided to transmit the torque of the machine tool 10 to the center drill 16. The torque of the machine tool 10 is transmitted from the adapter base body 20 to the center drill 16 by means of the quick-clamping element 36. The torque is transmitted by means of a positive connection between the quick-clamping element 36 and the center drill 16. The quick-clamping unit 34 has a locking element 58, which is provided to axially fix the center drill 16 in the receiving area 26. The locking element 58 is provided to fix the centering drill 16 axially in the receiving area 26 by means of a positive connection.The quick-clamping unit 34 has a spring 68, which is intended to press the locking element 58 radially against the center drill 16. The spring 68 and the locking element 58 are arranged in an opening 66, which is delimited by the quick-clamping element 36. The locking element 58 is designed as a ball. However, other designs for the locking element 58, which would appear appropriate to a person skilled in the art, are also conceivable, which make it possible to fix the center drill 16 axially in the receiving space 26 of the center drill 16 by means of its positive connection. The positive connection between the locking element 58 and the center drill 16 is established via the locking element 58 and a locking groove 70 arranged in the center drill 16, in particular in the flat surface 64 of the shank of the center drill 16.The center drill 16 is axially fixed by means of the frictional connection between the clamping surface 62 of the quick-action clamping element 36 and the center drill 16 and / or by means of the positive connection between the locking element 58 and the center drill 16. It is conceivable that the center drill 16 is axially fixed only by means of the positive connection by means of the locking element 58, in that the quick-action clamping element 36 is screwed into the adapter base body 20 only until the locking element 58 is arranged in the locking groove 70 of the center drill 16, but the clamping surface 62, when the machine tool 10 is not in operation, is free from contact with the center drill 16, in particular the flat surface 64 (Fig. 8).
[0032] The mandrel adapter device 12 has a rotary clamping unit 38, which is intended to axially fix and release the hole saw 18. The rotary clamping unit 38 comprises a bushing 40, which is connected, in particular in one piece, to the adapter base body 20 and completely encloses a part of the hole saw 18 received by the receiving area 28, and a sleeve 46 rotatably mounted on the bushing 40, which is intended to enable the fixation and release of the hole saw 18 by means of rotation. Figure 3 shows the adapter base body 20 with the bushing 40 integrally connected to the adapter base body. The bushing 40 is arranged between the sleeve 46 and the adapter base body 20. The bushing 40 is connected to the adapter base body 20 by means of a laser welding process.It is conceivable that the bushing 40 is connected to the adapter base body 20 by means of another method that appears appropriate to a person skilled in the art and is suitable for connecting the bushing 40, in particular in one piece, to the adapter base body 20, for example by means of an adhesive process and / or a welding process. It is also conceivable that the bushing 40 is screwed onto the adapter base body 20 by means of a thread and / or attached by means of a shrink connection. The bushing 40 has a smaller maximum longitudinal extent than the receiving area 26 of the center drill 16. The bushing 40 completely encloses the tool holder 24 in a plane perpendicular to the longitudinal extent of the tool holder 24. The bushing 40 and the outer circumferential surface 32 of the tool holder 24 form the receiving area 28 for the hole saw 18.The bushing 40 is designed as a hollow cylinder and has an inner bushing surface 72 and an outer bushing surface 74. The receiving area 28 for the hole saw 18 is delimited by the outer bushing surface 32 of the tool holder 24 and the inner bushing surface 72. The bushing 40 delimits a space having a hexagonal cross-sectional area. The bushing 40 is intended to transmit the torque from the machine tool 10 via the adapter base body 20 to the hole saw 18. The bushing 40 transmits the torque of the machine tool 10 by means of a positive connection between the bushing 40 and the hole saw 18. The positive connection between the bushing 40 and the hole saw 18 is created by the hexagonal design of the cross-sectional area of the space delimited by the bushing 40.The bushing's inner surface 72 and a portion of the sleeve's outer surface, which is received by the receiving area 28, are each hexagonal in shape to create the positive connection. The sleeve 46 has a smaller maximum longitudinal extent than the bushing 40. The sleeve 46 is hollow-cylindrical. The bushing 40 extends completely through the sleeve 46. The sleeve 46 has the same axis of rotation as the hole saw 18 and / or the center drill 16 (Fig. 3).
[0033] The rotary clamping unit 38 has two fixing elements 44 for fixing and releasing the hole saw 18, which fix or release the hole saw 18 depending on one of at least two rotational positions of the sleeve 46. The bushing 40 defines an opening 76 for each fixing element 44, which is intended to guide the fixing elements 44 in a radial direction into or out of the receiving space 28 of the hole saw 18. The sleeve 46 defines a cutout 78 for each fixing element 44. The two cutouts 78 are preferably intended to partially accommodate the two fixing elements 44, which are guided radially out of the receiving space 28 of the hole saw 18. The two fixing elements 44 are each designed as a ball. The rotary clamping unit 38 has the two rotational positions for the sleeve 46. A first of the two rotational positions is a fixing position for fixing the hole saw 18. The first rotational position, the fixing position, is shown in Figure 5.A second of the two rotational positions is a release position for releasing the hole saw 18. The second rotational position, the release position, is shown in Figure 4. The sleeve 46 is provided to press the two fixing elements 44 radially into the receiving space 28 of the hole saw 18 when the rotary clamping unit 38 is in the fixing position. The sleeve 46 is provided to provide the two fixing elements 44 with a retraction option from the receiving space 28 of the hole saw 18 in the release position by means of the two cutouts 78. The rotary clamping unit has a retaining ring 102. The retaining ring 102 is provided to axially fix the sleeve. The retaining ring 102 is arranged in front of the sleeve in the direction of view from the tool interface 22 to the tool holder 24. The bushing 40 has a groove which is provided to receive the retaining ring 102. The rotary clamping unit 38 has a positioning element 80.The positioning element 80 is designed as a pin. The bushing 40 delimits a plug-in opening 82. The plug-in opening 82 is intended to at least partially accommodate the positioning element 80. The sleeve 46 has a positioning groove 84. The positioning element 80 is intended to be arranged in the positioning groove 84 of the sleeve 46 when the rotary clamping unit 38 is in the assembled state. The positioning element 80 is intended to be guided by the positioning groove 84 when the sleeve 46 is rotated. The positioning groove 84 is delimited in a longitudinal direction by two walls 86 of the sleeve 46. The two walls 86 are intended to stop the positioning element 80 in the two rotational positions. The positioning element 80 is arranged in the positioning groove 84 such that the sleeve 46 is guided from one rotational position to the other when rotating between the two walls 86 of the positioning groove 84.A rotation angle 88 between the two rotation positions is 47° (Fig. 7).
[0034] The rotary clamping unit 38 has a return spring 48, which is intended to hold / reset the sleeve 46 in one of the two fixed positions. The return spring 48 is designed as a torsion spring. The return spring 48 has two legs 90, 92, each extending parallel to a rotational axis of the torsion spring. The two legs 90, 92 extend in opposite directions. When the rotary clamping unit 38 is in the assembled state, one of the two legs 90 is arranged in a spring leg holder 94 delimited by the bushing 40. A second of the two legs 92 is arranged in a further spring leg holder 96 delimited by the sleeve 46 when the rotary clamping unit 38 is in the assembled state. The return spring 48 completely encloses the bushing 40 in a plane perpendicular to the rotational axis of the bushing 40.The return spring 48 is provided to partially absorb and store a torque applied when rotating the sleeve 46. The sleeve 46 stores the torque applied to rotate the sleeve 46 from the fixing position to the release position. The return spring 48 is provided to return the sleeve 46 from the release position to the fixing position by means of the stored torque and / or with the torque from a preload of the return spring 48 and to hold it in the release position by means of a spring force and / or the preload of the return spring 48. The return spring 48 is preloaded to hold the sleeve 46 in the fixing position. The rotary clamping unit 38 is designed such that the sleeve 46 is rotated in one direction of rotation from the fixing position to the release position in order to release the hole saw 18.The direction of rotation for releasing the hole saw 18 is clockwise in a viewing direction from the tool interface 22 to the tool holder 24 (Fig. 6).
[0035] Figures 4 and 5 show the mandrel adapter device 12 in the two rotational positions. In Figure 5, the hole saw 18 is arranged in the receiving space 28. Figure 4 shows the mandrel adapter device 12 free of the hole saw 18 and the center drill 16. The rotary clamping unit 38 has a locking ring 52 and a further return spring 50, wherein the further return spring 50 is provided to press the two fixing elements 44 largely out of the receiving area 28 in the radial direction by means of the locking ring 52. The further return spring 50 is designed as a compression spring. The further return spring 50 is arranged in the receiving space 28 of the hole saw 18. The further return spring 50 is arranged after the locking ring 52 in an insertion direction of the hole saw 18. The locking ring 52 is provided to transfer an insertion force from the hole saw 18 to the further return spring 50 when inserting the hole saw 18.The insertion force is applied to press the hole saw 18 into the receiving space 28 of the further hole saw 18 against a spring force of the further return spring 50. The further return spring 50 is provided to store at least part of the insertion force. The further return spring 50 is provided to use the stored insertion force to press the two fixing elements 44 out of the receiving space 28 of the hole saw 18 by means of the locking ring 52. The locking ring 52 is arranged completely in the receiving space 28 of the hole saw 18. The locking ring 52 and the further return spring 50 completely enclose the adapter base body 20 in at least one plane perpendicular to the rotational axis of the adapter base body 20. The locking ring 52 is designed as an elastic snap ring. The locking ring 52 has holding arms 98 which extend inside the locking ring 52 in the direction of a rotation axis of the locking ring 52.The sleeve 46 is secured in the release position by radially pushing the two fixing elements 44 out of the receiving space 28 of the hole saw 18, particularly when the receiving space 28 of the hole saw 18 is free of the hole saw 18. The tool holder 24 has a region 100 with a reduced outer diameter. The region 100 with the reduced outer diameter is intended to secure the locking ring 52 by means of the holding arms 98 (Figures 4 and 5).
[0036] The bushing 40 has a radially outwardly projecting, circumferentially extending protective shoulder 54, which is arranged on a side of the adapter base body 20 facing away from the tool interface 22 and is intended to protect the sleeve 46 in the axial direction from external influences, in particular during operation of a machine tool 10. The spring leg holder 94 delimited by the bushing 40 is arranged in the protective shoulder 54 of the bushing 40 (Fig. 2). As can be seen in Figure 5, the sleeve 46 is arranged between the retaining ring 102 and the protective shoulder 54.
[0037] An assembly method for assembling the mandrel adapter device 12 is described below with reference to Figures 6 and 9. In an assembly step 104, the additional return spring 50 is pushed onto the adapter base body 20, into the receiving space 28 of the hole saw 18. In a further assembly step 106, the locking ring 52 is pushed onto the adapter base body 20, into the receiving space 28 of the hole saw 18. In the further assembly step 106, the locking ring 52 is pushed onto the adapter base body 20 after the additional return spring 50. When the locking ring 52 is pushed onto the adapter base body 20 in the further assembly step 106, the holding arms 98 elastically deform radially outward to enable sliding on. In the further assembly step 106, the locking ring 52 is pushed into the receiving area 28 of the hole saw 18 until it is arranged in the area 100 of the tool holder 24 with a reduced outer diameter.The holding arms 98 spring back elastically to their original shape when they have reached the area 100 with the reduced outer diameter.
Claims
Claims 1. Arbor adapter device (12) for mounting a hole saw unit (14), which comprises at least one centering drill (16) and a hole saw (18), on a machine tool (10), with at least one adapter base body (20) which comprises at least one tool interface (22) for mounting on the machine tool (10) and at least one tool holder (24) for receiving the hole saw unit (14), characterized by at least one, in particular circular cylindrical, receiving area (26) for the centering drill (16) and one, in particular hollow cylindrical, receiving area (28) for the hole saw (18), wherein the tool holder (24) is designed as a hollow cylindrical space with an inner surface (30) and an outer surface (32) and delimits the at least one, in particular circular cylindrical, receiving area (26) for the centering drill (16) with the inner surface (30) and the, in particular hollow cylindrical,The receiving area (28) for the hole saw (18) is at least partially limited by the outer surface (32), wherein the tool holder (24), in particular the entire adapter base body (20), is formed in one piece.
2. Clamping mandrel adapter device according to claim 1, characterized by a quick-clamping unit (34) with at least one quick-clamping element (36) which is arranged in a bore (60) of the adapter base body (20), wherein the quick-clamping unit (34) is provided to fix and release the centering drill (16) at least axially in the receiving area (26) of the centering drill (16).
3. Clamping mandrel adapter device according to claim 1 or 2, characterized by at least one rotary clamping unit (38) which is provided for axially fixing and releasing the hole saw (18), wherein the rotary clamping unit (38) comprises at least one bushing (40) connected, in particular integrally, to the adapter base body (20), which completely encloses at least one part of the hole saw (18) received by the receiving area (28), and at least one sleeve (46) rotatably mounted on the bushing (40), which is provided for enabling the fixing and releasing of the hole saw (18) by means of a rotation, wherein the bushing (40) is arranged between the sleeve (46) and the adapter base body (20).
4. Clamping mandrel adapter device according to one of the preceding claims, characterized in that the rotary clamping unit (38) for fixing and releasing the hole saw (18) has at least one fixing element (44), in particular two fixing elements (44), which, depending on one of at least two rotational positions of the sleeve (46), fix / fix or release the hole saw (18).
5. Clamping mandrel adapter device according to one of the preceding claims, characterized in that the rotary clamping unit (38) has at least one return spring (48) which is provided to hold / reset the sleeve (46) in a / a fixing position of the two rotation positions.
6. Clamping mandrel adapter device according to one of the preceding claims, characterized in that the rotary clamping unit (38) has at least one locking ring (52) and at least one further return spring (50), wherein the further return spring (50) is provided to push the at least one fixing element (44), in particular the two fixing elements (44), out of the receiving area (28) at least to a large extent, in particular in a radial direction, by means of the locking ring (52).
7. Clamping mandrel adapter device according to one of the preceding claims, characterized in that the bushing (40) has a radially outwardly has a circumferentially circumferential protective shoulder (54) which is arranged on a side of the adapter base body (20) facing away from the tool interface (22) and is designed to protect the sleeve (46) in the axial direction from external influences, in particular during operation of a machine tool (10).
8. Assembly method for assembling a mandrel adapter device (12) according to any one of the preceding claims.
9. Machine tool system comprising a machine tool (10) and a mandrel adapter device (12) according to any one of the preceding claims.