This nonprovisional application claims priority under 35 U.S.C. ยง 119(a) to German Patent Application No. 10 2019 121 049.6, which was filed in Germany on Aug. 5, 2019, and which is herein incorporated by reference
The present invention relates to a hand-held machine tool having a machine spindle rotatably mounted in a machine housing, to which a control member and at least one locking member are mounted so as to be radially adjustable and are adjustable between a change position and a locking position by an adjusting sleeve guided on the machine spindle, such that when the adjusting sleeve is moved to the change position, the control member is acted upon radially inward by the adjusting sleeve and the locking member is not acted upon by the adjusting sleeve, that the locking member is acted upon by the adjusting sleeve when adjusting the adjusting sleeve to the locking position, and that an adjusting ring for adjusting the adjusting sleeve mounted on the machine housing is provided between the change position and the locking position. The invention further relates to an assembly for a machine tool and to an adapter bushing.
Quick-change devices are known from the prior art, for example, for drilling machines by means of which the drill chuck mounted on the drill chuck can be replaced by another drill chuck or another tool; in this regard, reference can be made to DE 44 10 519 A1.
A disadvantage of the known quick-change systems is that the assignment of the changeover mechanism to the tool that is to be interchanged results in high costs, since the changeover mechanism must be designed in multiple ways.
It is therefore an object of the present invention to simplify the interchange of tools in hand-held machine tools.
The cooperation of a control member and a locking member simplify handling of the inventive machine tool, since the control member can force the proper alignment of the tool to be mounted on the machine tool, i.e. the control member is locked in the change position while the locking member can evade due to the lack of impingement by the adjusting sleeve. This facilitates the mounting of the tool, wherein after assembly and the change to the locking position, the locking member can perform its function by means of the impingement of the adjusting sleeve. The adjusting sleeve itself is designed such that it switches both the control member and the locking member in the desired manner when adjusting between the change position and the locking position, providing ease of use requiring no further active operation by the user, despite the use of a component in addition to the locking member, because the twisting of the adjusting ring alone is sufficient to call up the desired functions.
It is particularly preferred here that the machine spindle terminates with a hollow spindle, because this creates the possibility that the tool, which cooperates with the machine spindle and thus the machine tool, is not only fastened to the outside of the machine spindle, but also that a portion of the tool is introduced into the hollow spindle. In a machine tool equipped with a percussion mechanism it may also be possible to immerse in said hollow spindle. It is hereby expedient that the control member and the locking member are arranged at a mutual axial distance in a through hole of the machine spindle, and that the adjusting sleeve has a pocket on the inner peripheral surface and, axially adjacent to the pocket on both sides, has a contact surface on each of the two sides.
The radial adjustment of control member and locking member is thus directed inward, wherein the mutual axial distance makes it possible to position the adjusting sleeve between the control member and the locking member, and that by adjusting the adjusting sleeve, either one of the contact surfaces or the pocket are caused to respectively cooperate with the control member or the locking member. It is further provided that the adjusting sleeve is biased with a spring acting in the direction of the locking position so as to ensure permanent locking, in which the locking member is held in the through hole in the locking position by the contact surface of the adjusting sleeve.
The locking member can be provided in plurality in an arrangement distributed around the circumference of the machine spindle, and that the pocket is designed as a groove formed in the circumferential direction. This way, it is possible to even better secure the tool with respect to the machine spindle, wherein the multiple locking members provided are suited not only for axially securing the tool that is to be coupled with the machine tool, but also for improved torque transmission, i.e., it is not necessary to create additional structures for transmission of torque.
It is also expedient when the control member is designed as a control ball and the locking member as a locking ball, wherein the spherical shape ensures that the desired orientation is always provided. The locking ball and the control ball can thereby have the same diameter and be basically identically constructed. There is also the possibility of designing the control ball with a different diameter or from a different material, since the control ball is only effective in the change position with respect to the tool to be attached and does not itself have to transmit any forces.
For ergonomically improved, i.e. simplified, handling, it is provided that the adjusting ring be rotatably mounted between two catch positions associated with the change position of the locking position in the machine housing and have a control cam on the inside for the adjustment of the adjusting sleeve. Furthermore, the design is such that the control cam is assigned a spring wire which has no contact with the adjusting sleeve in the locking position. This is advantageous to the extent that during operation of the machine tool, the adjusting sleeve rotates because of its arrangement on the machine spindle.
The embodiment is also made in such a way that the axial front end of the machine housing is formed by a toothing plate that is non-rotatably connected to the machine housing and has a toothing extending in a circumferential direction. This toothing constitutes the axial cover of the machine housing and thus protects the spring wire and the adjusting sleeve against soiling. Since the toothing plate is non-rotatably connected to the machine housing, there is also the possibility of using the toothing with a positive connection to fix a tool to be mounted on the machine tool relative to the machine housing.
Thus, the toothing plate covers the spring wire and the adjusting ring and is supplemented by a locking ring arranged on the machine spindle. This offers improved protection against soiling, because due to the distance between the toothing plate and the machine spindle, the play resulting therefrom can be taken into account.
The machine spindle can be designed in two parts with the terminal part of the machine spindle being combined into a retrofittable assembly with the control member, the locking member, the adjusting sleeve and the adjusting ring, providing a separately realizable and usable good. This opens up the possibility of equipping an existing machine tool with the assembly and thus creating the possibility of attaching a quick-change mechanism to the machine tool. It then becomes possible that the terminal part of the machine spindle has a spindle holder with a female thread, because this way, the retrofittable assembly can be fixed on the machine spindle associated with the machine housing in the usual manner, comparable to a chuck body with a spindle holder. Optionally, as long as the machine-side machine spindle is configured for it, a screw for locking can also be used in a screw attachment.
The assembly can have a clamping sleeve for cooperating with the machine housing so as to simplify mounting the assembly on the machine tool.
An adapter bushing can be provided, which provides a separately realizable and useable good, having a sleeve that can be inserted in the hollow spindle, comprising the axially extending groove for cooperation with the control member and a number of spherical indentations corresponding to the number of locking members for cooperating with the locking members. The adapter bushing can thus be fixedly attached to a tool, wherein the axially extending groove allows for the effect of the control member to develop, and the formed spherical indentations cause the axial locking and rotational entrainment of the adapter bushing with respect to the machine spindle. In particular, at the end axially opposite the sleeve, the adapter bushing comprises a threaded portion for screwing into the threaded receptacle of a tool body or is designed in one piece with the tool body of a tool. This adapter bushing also makes it possible to retrofit the tool for use with the quick-change mechanism, thus creating a combination of the machine tool, the adapter bushing and the tool. Of course it is also possible that the adapter bushing is already integrated in the tool, i.e. the adapter bushing is integrally designed with the tool body, if the tool is already being serially used with the quick-change mechanism.
The tool can be, for example, a drill chuck, an angle attachment, a bit holder, a square mount, a collet chuck. In addition, there is also the possibility for the tool to have a toothing, which is complementary to the toothing plate on the side facing the machine tool, for fixing the position relative to the machine housing. This is particularly advantageous when using an angle attachment or other attachments which have to be positively connected to the stationary part of the machine, since this way the attachment is radially fixed to the machine housing.
The assembly with the terminal part of the machine spindle, including the control member, the locking member, the adjusting sleeve and the adjusting ring as well as the adapter bushing comprising the sleeve insertable in the hollow spindle, which sleeve has an axially extending groove for cooperation with the control member and a number of spherical indentations corresponding to the number of locking members for the cooperation with the locking members and has a threaded portion for screwing into the threaded receptacle on the side axially opposite the sleeve, are technically independently realizable components which allow for the retrofitting of machine tools and tools for use in the advantageous quick-change system.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes, combinations, and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
In order to execute a quick-release mechanism, a control member 6 and at least one locking member 7 are mounted in the machine spindle 4 so as to be radially adjustable, which can be adjusted between a change position and a locking position by an adjusting sleeve 8 guided on the machine spindle 4. The adjustment option is thereby such that when adjusting the adjusting sleeve 8 to the change position, the control member 6 is radially inwardly acted upon by the adjusting sleeve 8 and the locking member 7 is not acted upon by the adjusting sleeve 8. These configurations in the change position are shown in
In contrast,
The axial front end of the machine housing 2, or accordingly, of the assembly 17, is formed by a toothing plate 22 which is rotationally fixed to the machine housing 2, which is formed with a toothing 23 extending in the circumferential direction.
The above-described components are provided to cooperate with an adapter bushing 24 having a sleeve 25 that can be inserted in the hollow spindle 13, which sleeve comprises a radially extending groove 26 for the cooperation with the control member 6 and a number of spherical indentations 27 corresponding to a number of locking members 7 for cooperation with the locking members 7. This adapter bushing 24 may be integrally formed with the tool body of a tool 5 or comprise a threaded portion at the end that is axially opposite the sleeve 25 for screwing into the threaded receptacle of a tool body.
Below, the handling of the machine tool 1 will now be briefly described when changing a tool 5. The basis is the configuration shown in
After changing from the change position to the locking position by the rotation of the adjusting ring 9 from one catch position to the other catch position, the configuration according to
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.
Number | Date | Country | Kind |
---|---|---|---|
10 2019 121 049.6 | Aug 2019 | DE | national |