Drill chuck and drilling machine

Abstract

The invention relates to a drill chuck (1) comprising a chuck body (2) which is provided at its rear end with a spindle receptacle (3) and at its axially forward end with a tool receptacle (4) into which a chuck jaw (6) which is movably guided in a guide channel (5) of the chuck body (2) projects. An annular collar (11) having a non-circular first outer circumference (12) projects axially rearward from the axially rearward end of the chuck body (2). A drive sleeve (13) which is mountable on the annular collar (11) is provided, which drive sleeve has a first inner circumference (15) which is adapted to the first outer circumference (12) for torque transmission. The axial extension of the drive sleeve (13) is greater than the axial extension of the annular collar (11). The invention also relates to a drilling machine.

Description

[0001] This invention relates to a drill chuck, comprising a chuck body having a spindle receiving portion at its rear end and a tool receiving portion at its axial front end. A jaw is slidably guided within a guide channel of the chuck body to enter the tool receiving portion. An annular collar having a non-circular first outer circumference extends axially rearward from the axial rear end of the chuck body. A drive sleeve is provided, which can be mounted on the annular collar and has a first inner circumference adapted to the first outer circumference for transmitting torque. The axial length of the drive sleeve is greater than the axial length of the annular collar. This invention also relates to a drilling rig.

[0002] EP0710518A2 discloses a drill chuck, and reference can be made to this publication, which reflects the basic structure and operating mode of a drill chuck known to a person skilled in the art. DE202013101255U1 discloses a drill chuck having a chuck body with a bearing formed at the rear end of the chuck body for connection with a drill spindle of a drilling rig. The bearing has an internal thread, into which the drill spindle can be screwed externally. A channel formed in the chuck body is used to axially fix the drill chuck relative to the drill spindle, and a locking screw can be screwed into a screw receiver on the drill spindle through this channel.

[0003] Modern drilling rigs are becoming increasingly powerful, capable of generating high torques exceeding 200 Nm. This torque must be safely transmitted to the drill chuck without overloading the connection between the chuck body and the drill spindle or affecting its ability to be subsequently released, allowing for chuck replacement. In particular, it is crucial to ensure the drill spindle does not break, as detachment of the drill chuck during operation could endanger the user. Increasing material thickness is not a feasible solution here, as the drill chuck's outer diameter should not exceed 43 mm, a value accepted in the industry, and the relevant dimensions are designed accordingly.

[0004] Therefore, an object of the present invention is to provide a drill chuck capable of transmitting high torque, while allowing users to replace the drill chuck on the drill spindle without having to visit a service center. Another object is to provide a drilling rig suitable for driving the drill chuck.

[0005] This objective is achieved by a drill chuck having the features of claim 1 and a drilling rig having the features of claim 13. Advantageous embodiments with beneficial modifications to the invention are set forth in the dependent claims.

[0006] The drill chuck described at the outset improves power transmission from the drill spindle of a drilling rig because, instead of the widely used threaded connection between the spindle and the drill chuck responsible for power transmission, an annular collar with a non-circular first outer circumference now protrudes axially rearward from the axial rear end of the chuck body. A drive sleeve is provided, which can be mounted on the annular collar. This drive sleeve has a first inner circumference adapted to the first outer circumference for transmitting torque, and the axial length of the drive sleeve is greater than the axial length of the annular collar. Torque transmission is achieved through the interaction between the annular collar and the drive sleeve; that is, the transmission is independent of any axial locking of the spindle, and therefore the axial locking is also unaffected by the applied torque. This invention ensures ease of manufacture for both the spindle and the chuck body.

[0007] To increase the material thickness of the drive sleeve, multiple channels can be formed on the second outer periphery of the drive sleeve. These channels correspond at least to the number of grippers, allowing the grippers to pass through. Therefore, the guidance of the grippers and their position need not be limiting factors in selecting the drive sleeve wall thickness. Guiding surfaces for the grippers can be formed within the channels.

[0008] Particularly preferred is that the first outer and first inner circumferences are designed as polygons, as this allows high torque to be transmitted before shear forces cause deformation of the drive sleeve. Preferably, the polygon is formed of a hexagon, although different numbers of sides between 3 and 8 can also be achieved. If a hexagon is chosen, providing 3 channels is sufficient in the case of a typical drill chuck with 3 jaws; however, providing 6 channels spaced at 60° intervals prevents misassembly. The compactness of the design is enhanced if the polygon, especially the hexagon, is aligned with the guide channels such that the surface connecting the edges, rather than the edges, faces the jaws.

[0009] A further preferred embodiment is the formation of an assembly receiving portion, which is a stepped section extending axially forward from the axial rear end of the sleeve body toward the spindle receiving portion, wherein a channel extends from the assembly receiving portion to the tool receiving portion. Preferably, the diameter of the assembly receiving portion is 12 mm, as this allows the chuck body to have sufficient remaining material thickness in this area while maintaining good remaining thickness of the spindle.

[0010] The diameter of the channel is smaller than the diameter of the assembly housing, so the assembly housing can also function as a stop. An internal thread can be formed in the channel. This internal thread is not necessarily, or primarily, used for connecting the spindle to the chuck body and axially fixing the spindle, but rather allows the spindle to be pushed out of the spindle housing using an ejector screw, which is particularly advantageous if corrosion occurs in the interface area between the spindle and the chuck body under adverse climatic conditions.

[0011] On the other hand, this internal thread can be used for the assembly and machining of drill chucks, since threads for these purposes (for fixing the spindle) are not necessarily available. Especially during grinding, a great deal of extra work is avoided because locking screws and their assembly and disassembly are not required.

[0012] If a recess extending from the tool holder to the channel is formed in the channel, and the recess is offset axially forward, the head of the locking screw can be inserted into the recess without interfering with the tool or workpiece to be inserted into the tool holder.

[0013] Preferably, the diameter of the internal thread of the channel is larger than the diameter of the locking screw extending through the channel, because this prevents the locking screw from engaging with the internal thread and avoids interaction between the locking screw and the internal thread.

[0014] The aforementioned advantages and effects also apply to the drill chuck according to the above embodiment, which is combined with a drilling machine having a drill spindle, wherein the drill spindle has a mating portion with a non-circular second outer periphery at its axial end facing the drill chuck, the shape of the second outer periphery corresponding to the shape of the first outer periphery. Preferably, the drill spindle is characterized by a spindle journal with a journal diameter matching that of the mounting housing, extending axially from the mating portion to its free end to provide guidance within the mounting housing. The axial length of the drive sleeve ensures that the mating portion can also enter the drive sleeve.

[0015] In addition, an ejector screw can be provided, the outer diameter of which matches the diameter of the internal thread of the channel. When the ejector screw is screwed into the internal thread, the drill spindle of the drill can be ejected from the spindle housing through the ejector screw.

[0016] The design of the drill chuck allows for the formation of a combination of the aforementioned type of drill chuck and a chuck that houses the drill spindle, wherein the drill spindle has an engagement portion at its axial end facing the drill chuck, the engagement portion having a non-circular second outer periphery, the shape of the second outer periphery corresponding to the shape of the first outer periphery.

[0017] Preferably, the drill spindle has a spindle journal extending axially from the engagement portion toward its free end. This spindle journal has a spindle diameter that matches the assembly housing for guidance within the assembly housing, as this facilitates and enables the spindle to be centered relative to the chuck body.

[0018] When the end face of the joint portion axially facing the free end of the drill spindle is designed as a first plane, better positioning of the spindle relative to the chuck body is achieved. In this case, it is advantageous if the axial rear end of the chuck body is also designed as a second plane that interacts with the first plane.

[0019] The spindle can be aligned with its journal in the spindle housing via an interference fit, thereby simplifying axial locking. Due to the design of the drive sleeve according to the invention, which transmits torque between the spindle and the chuck body, a torque greater than 200 Nm can be transmitted. Axial fixation of the spindle can be achieved completely independently of torque transmission by means of a locking screw, particularly an M6 size locking screw, which extends from the tool housing through a channel to the spindle housing and can be screwed into a threaded housing formed in the spindle, thereby pulling the spindle axially downward onto the chuck body via a first and second plane.

[0020] The features and combinations thereof described above in the specification, as well as the features and combinations thereof mentioned in and / or shown individually in the accompanying drawings, are not limited to the specific combinations shown, but may be used in other combinations or individually without departing from the scope of the invention. Therefore, embodiments not explicitly shown or described in the drawings but derived and produced from the described embodiments by individual combinations of features will also be considered as covered and disclosed by the invention.

[0021] Other advantages, features, and details of the invention will become apparent from the claims, the following description of preferred embodiments, and the accompanying drawings. The drawings illustrate: Figure 1 This is a longitudinal cross-sectional view of a drill chuck, which has an attached spindle that is part of a drilling rig or machine tool; Figure 2 A perspective view of a drill chuck with a separate drive sleeve and a separate spindle; Figure 3 for Figure 1 A perspective view of the object shown; Figure 4 A side view of a drill chuck with a spindle is shown, in partial cross-section. Figure 5 For corresponding Figure 4 The view shows a combination of a drill chuck and a grinding spindle or a mounting spindle; Figure 6 For corresponding Figure 4 The view shows the combination of the drill chuck and the ejector screw; Figure 7 A perspective view of an isolated principal axis; Figure 8 for Figure 7 The side view of the main shaft shown is illustrated in partial section; and Figure 9 For corresponding Figure 4 A view of an isolated drill chuck.

[0022] Figure 1A drill chuck 1 with a chuck body 2 is shown. The chuck body 2 has a spindle receiving portion 3 at its rear end and a tool receiving portion 4 at its axial front end. A jaw 6, which is slidably guided in a guide channel 5 of the chuck body 2, leads to the tool receiving portion 4. An annular collar 11 with a non-circular first outer circumference extends axially rearward from the rear end of the chuck body 2. Figure 2 Specifically, a drive sleeve 13 is provided, which can be mounted onto the annular collar 11 and has a first inner circumference 15 adapted to a first outer circumference 12 for transmitting torque. The axial length of the drive sleeve 13 is greater than the axial length of the annular collar 11.

[0023] Figure 2 It is also shown that the second outer periphery 24 of the drive sleeve 13 has a plurality of channels 25, corresponding to the number of grippers 6, for guiding the grippers 6, wherein, in the illustrated embodiment, a guide surface for the grippers 6 is formed in the channels 25. The number of channels 25 may also be greater than the number of grippers 6, that is, this prevents misalignment of the grippers 6 when positioning the drive sleeve 13.

[0024] In this embodiment, the first outer periphery 12 and the first inner periphery 15 are designed as polygons, i.e., hexagons. The hexagons are oriented in a rotational position on the chuck body 2 such that their three keyways face the jaws 6. In this embodiment, channels 25 may also be formed on each keyway to prevent misalignment.

[0025] Figure 1 and Figure 3 As shown, an assembly receiving portion 9 is formed in the tool body 2 from the axial rear end of the chuck body. The assembly receiving portion 9 is axially offset forward from the spindle receiving portion, and a through hole 10 extends from the assembly receiving portion 9 to the tool receiving portion 4. The diameter of the assembly receiving portion 9 is, for example, 12 mm. The figure also shows that the diameter of the channel 10 is smaller than the diameter of the assembly receiving portion 9.

[0026] Internal thread 16 is formed in channel 10. Figure 5 The illustrated embodiment demonstrates its combined use with a grinding spindle 23 or a mounting spindle, which can be used to manufacture the drill chuck 1, and whose assembly is significantly simplified by the internal thread 16.

[0027] The recess 18 extending from the tool receiving portion 4 to the channel 10 is formed to be offset axially forward from the channel 10, into which the head 20 of the locking screw 19 can be inserted. The diameter of the internal thread of the channel 10 is larger than the diameter of the locking screw 19 passing through the channel.

[0028] The aforementioned drill chuck 1 can be combined with a drilling rig having a drill spindle 21, wherein the drill spindle 21 has a engagement portion 26 at its axial end facing the drill chuck 1. This engagement portion 26 has a non-circular second outer periphery 27, the shape of which corresponds to the shape of the first outer periphery 12. This engagement portion 26 can engage with the drive sleeve 13 during assembly; for this purpose, the engagement portion 26 is shaped to fit the shape of an annular collar. Furthermore, the axial length of the drive sleeve 13 is selected such that the engagement portion 26 and the annular collar 11 can be engaged and fitted into the drive sleeve 13, thereby establishing a torque transmission connection capable of withstanding high loads between the spindle 14 and the chuck body 2. The axial end face of the engagement portion 26 facing the free end of the drill spindle 21 is designed as a first flat surface 22 and is intended and adapted to interact with a second plane 28 on the axial rear end of the chuck body 2. The spindle journal 29 is used to center the spindle within the assembly housing 9.

[0029] Figure 2 The diagram illustrates how the spindle housing 3 is used to connect to the spindle 14, which is shown separately but as a drilling spindle 21, part of a drilling machine, or as a grinding spindle 23. A locking screw 19 is used to axially secure the spindle 14 in the spindle housing 3; its screw head 20 engages in and is positioned in the countersunk hole 18. The locking screw 19 pulls the first plane 22 of the spindle 14 toward the second plane 28 of the chuck body 2, thereby fixing the axial position. The radial position of the spindle 14 is determined by an interference fit 9, which also serves for centering. Figure 5 This demonstrates the possibility that, for lower loads, such as when the grinding spindle 23 is placed in the spindle housing 3, the through hole 10 with internal threads 16 can also be used to secure the grinding spindle 23, which means that there is no need to install or remove the locking screw 19.

[0030] After removing the locking screw 19, an inlet to the channel 10 with internal threads 16 is exposed. Using the set screw 17 screwed into the internal threads 16, the drill spindle 21 or grinding spindle 23 can be axially pushed out of the spindle housing 3. Figure 6 ).

[0031] List of reference numerals in the attached diagram: 1. Drill chuck; 2. Chuck body; 3. Spindle housing; 4. Tool housing; 5. Guiding channels; 6 grippers; 7. Longitudinal axis; 8 grooves; 9. Assembly and housing section; 10 through holes; 11. Circular assembly section; 12. First periphery; 13 drive sleeve; 14 spindles; 15 first inner week; 16 internal thread; 17 Set screws; 18 concavities; 19 locking screws; 20 screw head; 21 Drilling Spindle; 22 First plane; 23 Grinding spindle; 24 second periphery; 25 channels; 26. Joint portion; 27 second periphery; 28. Second plane; 29. Spindle journal.

Claims

1. A drill chuck (1), comprising a chuck body (2), the chuck body having a spindle receiving portion (3) at its rear end and a tool receiving portion (4) at its axial front end, wherein a jaw (6) slidably guided within a guide channel (5) of the chuck body (2) leads into the tool receiving portion, characterized in that, An annular collar (11) having a non-circular first outer periphery (12) extends axially rearward from the axial rear end of the chuck body (2), wherein a drive sleeve (13) is provided, the drive sleeve being mountable on the annular collar (11) and having a first inner periphery (15) adapted to the first outer periphery (12) for transmitting torque, and wherein the axial length of the drive sleeve (13) is greater than the axial length of the annular collar (11).

2. The drill chuck (1) according to claim 1, characterized in that, The second outer periphery (24) of the drive sleeve (13) is formed with a plurality of channels (25) for guiding the grippers (6), the number of channels (25) being at least the number of grippers (6).

3. The drill chuck (1) according to claim 1 or 2, characterized in that, The first outer perimeter (12) and the first inner perimeter (15) are designed as polygons.

4. The drill chuck (1) according to claim 4, characterized in that, The polygon is formed by hexagons.

5. The drill chuck (1) according to any one of claims 1 to 4, characterized in that, An assembly receiving portion (9) is formed axially forward from the spindle receiving portion (3) at the axial rear end of the chuck body (2), and a channel (10) extends from the assembly receiving portion (9) to the tool receiving portion (4).

6. The drill chuck (1) according to claim 5, characterized in that, The diameter of the hole (10) is smaller than the diameter of the assembly receiving part (9).

7. The drill chuck (1) according to claim 5 or 6, characterized in that, An internal thread (16) is formed in the channel (10).

8. The drill chuck (1) according to any one of claims 5 to 7, characterized in that, A recess (18) extending from the tool receiving portion (4) to the channel (10) is formed in front of the channel (10) axially.

9. The drill chuck (1) according to any one of claims 5 to 8, characterized in that, The diameter of the internal thread (16) of the channel (10) is greater than the diameter of the locking screw (19) extending through the channel.

10. The drill chuck (1) according to any one of claims 1 to 9, which is combined with a drilling rig including a drill spindle (21), characterized in that, The drill spindle (21) includes a joint portion (26) with a non-circular second outer periphery (27) at its axial end facing the drill chuck (1), the shape of the second outer periphery corresponding to the shape of the first outer periphery (12).

11. The drill chuck (1) according to claim 10, characterized in that, The drill spindle (21) includes a spindle journal (29) extending axially from the engagement portion (26) toward its free end for guidance in the assembly receiving portion (9), the spindle journal (29) having a shape that matches the assembly receiving portion (9).

12. The drill chuck (1) according to any one of claims 5 to 11, characterized in that, A set screw (17) is provided, the outer diameter of which matches the diameter of the internal thread (16) of the channel (10).

13. A drilling rig having a drill spindle (21), characterized in that, The drill spindle (21) has a joint portion (26) at its axial end facing the drill chuck (1), the joint portion (26) having a non-circular second outer periphery (27) the shape of which corresponds to the shape of the first outer periphery (12).

14. The drilling rig according to claim 13, characterized in that, The drill spindle (21) includes a spindle journal (29) extending axially from the engagement portion (26) to its free end for guidance in the assembly receiving portion (9), the spindle journal (29) having a spindle diameter that matches the assembly receiving portion (9).

15. The drilling rig according to claim 13 or 14, characterized in that, The end face of the joint portion pointing axially toward the free end of the drill spindle (21) is designed as a first plane (22).

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