Hand-held power tool device

Abstract

The invention is based on a hand-held power tool device equipped with a locking device. The locking device is provided for locking an output device and has at least one locking element for supporting at least one radial clamping force. According to a proposed embodiment, the locking element is provided to fasten and/or axially secure at least one component.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patent application Ser. No. 12/951,698, filed on Nov. 22, 2010, which claims priority to and the benefit of German Patent Application No. 10 2009 054 929.3, filed on Dec. 18, 2009, the contents of each of which are hereby incorporated by reference in their entireties.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention is based on a hand-held power tool device equipped with a locking device, which is for locking an output device and has at least one locking element for supporting at least one radial clamping force.

Description of the Prior Art

There is already a known hand-held power tool device, in particular for a screwdriver, equipped with a locking device, which is for locking an output device in the form of a spindle and has a locking element embodied in the form of a clamping ring for supporting radial clamping forces of clamping elements composed of rollers.

SUMMARY AND ADVANTAGES OF THE INVENTION

According to one proposed embodiment, the locking element is provided for fastening at least one component. In this connection, a “locking device” should in particular be understood to be a device that is provided to disable and/or inhibit an output device and/or a rotary motion of the output device in at least one operating state. An “output device” should in particular be understood here to be a device that is provided to transmit a driving power and that preferably has at least one output shaft that a motor drives in an operating state of the hand-held power tool. The term “radial” here should in particular be understood to be radial to a rotation axis of the rotary motion of the output device to be locked. In addition, a “clamping force” should in particular be understood to be a force that is produced by a clamping procedure as part of the locking action. Preferably, the output shaft drives a tool to rotate during operation, for example a screwdriver, a drill, a boring chisel, a milling tool, etc. The term “provided” should in particular be understood to be specially equipped and/or designed. In addition, the term “fastening” should in particular be understood to mean that in the fully assembled state of a hand-held power tool with the hand-held power tool device, the locking element is used for fastening an additional component; the additional component is fixed firmly in place with the locking element and the locking element supports a bearing force of the component. An “axial securing” should in particular be understood to mean that a bearing force of the component, in particular a transmission component, is supported by the locking element in the axial direction, i.e. particularly in the direction of a rotation axis of the output device. The locking element in this case is preferably manufactured at least partially out of a metallic material. Particularly preferably, the locking element is embodied in the form of a screw-mounting flange to which at least one component, in particular a transmission component, can be fastened and/or axially secured by means of a screw connection.

Through a corresponding embodiment, a component—which must have a fundamentally rugged construction—can be advantageously used to support additional bearing forces. It is advantageously possible to reduce mechanical and thermal stresses on housing parts, in particular plastic housing parts. It is also advantageously possible, by fastening an additional component to the locking element, to achieve an advantageous reinforcing of the locking element, allowing the latter to be embodied in a particularly space-saving and light-weight fashion.

The locking element can be composed of various components deemed suitable by the person skilled in the art, e.g. one or more annular segments, etc. It is particularly advantageous, however, for the locking element to be composed of a clamping ring that preferably extends over 360°, advantageously permitting forces to be supported.

If the hand-held power tool device has a housing unit in which the locking element is supported with a radial play of less than 0.1 mm and particularly advantageously, less than 0.05 mm and particularly preferably, in which the locking element is affixed without play in the radial direction, then in particular, bearing forces of the component, which is to be fastened by means of the locking element, can be supported in an advantageously determined fashion, in particular without play.

The locking element can be fastened in a housing unit equipped with fastening elements such as screws, clamping elements, etc. and/or can be pressed-fitted into a housing unit. In a particularly advantageous embodiment, however, the housing unit is molded around the locking element, i.e. in a manufacturing process of the housing unit, the locking element is in particular inserted into an injection mold and then a material of which the housing unit is at least partially manufactured, in particular such as plastic, is injection molded around it. Through a corresponding embodiment, it is possible to achieve an advantageously inexpensive design, particularly in that the locking element can be manufactured within broad tolerances with regard to its outer contour.

According to another proposed embodiment of the invention, the hand-held power tool device has a pivot bearing unit that is provided to support the output device and includes the component to be fastened, which is composed of a bearing component. The term “pivot bearing unit” here should in particular be understood to mean a unit that is provided for the rotating support of a component of the output device and in particular, has at least one slide bearing and/or rolling bearing. Through a corresponding embodiment, it is possible in particular to achieve an advantageous reinforcement of the locking element, advantageously providing savings with regard to space, in particular a length of the installation space, particularly if the bearing component and the locking element are situated in at least one common plane extending perpendicular to a rotation axis of the pivot bearing unit. The bearing component can be fastened to the locking element using various fastening elements deemed suitable by the person skilled in the art, e.g. screws, clamping elements, etc. It is particularly advantageous, however, for the hearing component to he connected to the locking element by means of a press-fitted connection, making it possible to advantageously avoid undesirable tolerances in a structurally simple fashion. In this connection, it is particularly preferable for the bearing component, e.g. a ring element, to be press-fitted into a recess of the locking element.

According to another proposed embodiment, the locking element is provided for axially securing at least one output shaft and/or at least one adjusting element, once again reducing stresses on housing components and enabling savings with regard to components, space, and weight. An “adjusting element” should in particular be understood to be an element that is provided for being actuated by a user and/or an actuator during an adjustment, e.g. when setting of a maximum torque, etc.

According to another proposed embodiment, the locking element is provided for directly supporting an output shaft. The term “directly” here should in particular be understood to mean that the locking element and the output shaft contact each other with corresponding bearing surfaces directly, i.e. without interposed components. With a corresponding embodiment, the locking element—which must have a fundamentally rugged construction—can be advantageously used to directly support a bearing force, thus permitting savings in terms of components, space, weight, and assembly complexity.

If the locking element in this case is manufactured out of a sintered material, particularly advantageous sliding properties can be achieved in a structurally simple fashion.

The embodiment according to the invention, i.e. the hand-held power tool device according to the invention, can be used in various hand-held tools deemed suitable by the person skilled in the art, e.g. in angle grinders, milling machines, power saws, power drills, impact drills, and rotary hammers. The embodiment according to the invention can be used to particular advantage in cordless devices due to the particularly advantageous possibilities for savings in terms of components, space, and weight.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings, in which:

FIG. 1 shows a hand-held power tool equipped with a hand-held power tool device according to the invention;

FIG. 2 shows a detail of a longitudinal section through the hand-held power tool from FIG. 1; and

FIG. 3 shows a detail of a longitudinal section through an alternative hand-held power tool.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 schematically depicts a hand-held power tool embodied in the form of a cordless impact drill/screwdriver 34a, having a drive motor 38a that is accommodated in a machine housing 36a and is able to drive an output shaft 18a of an output device 12a via a planetary gear set 40a that is not depicted in detail (FIGS. 1 and 2). The output shaft 18a has a clamping chuck 42a fastened to it. The clamping chuck 42a has a clamping device 44a that can be actuated in order to fasten a tool in the rotation direction 46a around a rotation axis 28a of the output device 12a relative to the machine housing 36a.

The hand-held power tool also has a hand-held power tool device with a locking device 10a for locking the output shaft 18a of the output device 12a (FIG. 2). The locking device 10a is used to couple the output shaft 18a in a rotationally fixed fashion in relation to the machine housing 36a when the tool is being clamped and released by means of the clamping device 44a. The locking device 10a is automatically opened or more precisely stated, automatically releases the output shaft 18a, when a torque is transmitted from the drive motor 38a to the clamping chuck 42a and is automatically closed or more precisely stated, automatically immobilizes the output shaft 18a, when a torque is transmitted from the clamping chuck 42a to the drive motor 38a.

The locking device 10a includes a locking element 14a, which is embodied in the form of a clamping ring, for supporting radial clamping forces 16a. Inside the locking element 14a, clamping elements 48a are situated between the locking element 14a and the output shaft 18a and, in order to lock the output shaft 18a when a torque is transmitted from the clamping chuck 42a to the drive motor 38a, are moved in the circumference direction into tapering gaps, thus producing the radial clamping forces 16a and locking the output shaft 18a in the rotation direction 46a. The clamping elements 48a are embodied in the form of rollers. When a torque is transmitted from the drive motor 38a to the clamping chuck 42a, the clamping elements 48a are carried along by catch elements 50a of a catch device 52a so that the clamping elements 48a are prevented from jamming inside the locking element 14a. The catch device 52a is embodied of one piece with a planet carrier of the planetary gear seat 40a.

The locking element 14a is provided for fastening and axially securing components. The locking element 14a is affixed without play in the radial direction in a housing unit 20a of the machine housing 36a, which housing unit is manufactured out of plastic; in fact, the housing unit 20a is molded around the locking element 14a. The hand-held power tool device includes a pivot bearing unit 22a that is provided to support the output shaft 18a of the output device 12a at an end oriented toward the drive motor 38a and includes one of the components to be fastened, which is constituted by a bearing component 24a. The bearing component 24a and the locking element 14a are connected to each other by means of a press-fitted connection 26a. The bearing component 24a is constituted by an outer ring of a rolling bearing and is pressed-fitted into an inner circumference of the locking element 14a. The bearing component 24a and the locking element 14a arc situated in common planes 30a extending perpendicular to a rotation axis 28a of the pivot bearing unit 22a. The bearing component 24a is situated completely inside an axial region defined by the locking element 14a.

During operation, an inner bearing ring 54a of the pivot bearing unit 22a serves as an axial stop element for the clamping elements 48a, making it possible to advantageously prevent a relative movement between the clamping elements 48a and the inner bearing ring 54a and a resulting generation of heat. The inner bearing ring 54a is press-fitted onto the output shaft 18a. If the output shaft 18a is loaded in the direction toward the clamping elements 48a, then the inner bearing ring 54a is shifted slightly toward the clamping elements 48a in relation to the bearing component 24a so that the inner bearing ring 54a can advantageously function as a stop element.

The locking element 14a also serves to axially secure the output shaft 18a and an adjusting element 32a (FIG. 1). For this purpose, a securing means, not shown, which constitutes an axial stop for the output shaft 18a and an axial stop for the adjusting element 32a, is fastened to the locking element 14a by means of axial fastening means 56a. The fastening means 56a are constituted by screws that are screwed into internal threads 58a of the locking element 14a. The locking element 14a constitutes a screw flange.

FIG. 3 shows an alternative exemplary embodiment. Components, features, and functions that remain the same have essentially been provided with the same reference numerals. To differentiate between the exemplary embodiments, however, the letters a and b have been added to their respective reference numerals. The description below is essentially limited to the differences as compared to the exemplary embodiment shown in FIGS. 1 and 2; with regard to components, features, and functions that remain the same, the reader is referred to the description of the exemplary embodiment shown in FIGS. 1 and 2.

FIG. 3 shows a hand-held power tool device with a locking element 14b that is provided for directly supporting an output shaft 18b. The locking element 14b constitutes a slide bearing surface 60b by means of which the locking element 14b directly contacts the output shaft 18b. The locking element 14b is manufactured out of a sintered material. Essentially, however, it is also conceivable for it to be made of any other material deemed suitable by the person skilled in the art.

It is also conceivable for a slide bearing 62b to be press-fitted into the locking element 14b, as indicated in FIG. 3.

The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.

Claims

1. A hand-held power tool device, comprising: an output device including an output shaft;a locking device configured to lock the output shaft, the locking device including: at least one locking element embodied as a clamping ring and configured to support at least one radial clamping force;at least one clamping element embodied as a clamping roller; andat least one catch element configured to entrain the at least one clamping element; anda bearing unit configured to support the output shaft, the bearing unit including a bearing component,wherein the bearing component and the clamping ring are arranged in at least one first common plane extending perpendicular to a rotation axis of the output shaft; wherein the at least one clamping roller, the clamping ring, and the at least one catch element are arranged in at least one second common plane extending perpendicular to the rotation axis of the output shaft and parallel to the at least one first common plane.

2. The hand-held power tool device as recited in claim 1, wherein the bearing component is arranged completely within an axial extension of the clamping ring.

3. The hand-held power tool device as recited in claim 1, wherein the bearing component and the at least one clamping roller are arranged completely within an axial extension of the clamping ring.

4. The hand-held power tool device as recited in claim 1, wherein the at least one clamping roller and the clamping ring are arranged in at least one second common plane extending perpendicular to the rotation axis of the output shaft and parallel to the at least one first common plane.

5. The hand-held power tool device as recited in claim 1, wherein the bearing component is fixedly connected to an inner surface of the clamping ring.

6. The hand-held power tool device as recited in claim 1, wherein the bearing component is fixedly connected to the inner surface of the clamping ring by means of a press-fit connection.

7. The hand-held power tool device as recited in claim 1, wherein the bearing unit is embodied as a roller bearing, wherein the bearing component is embodied as an outer bearing ring of the roller bearing.

8. The hand-held power tool device as recited in claim 7, wherein the roller bearing includes an inner bearing ring which is directly supported on the output shaft.

9. The hand-held power tool device as recited in claim 8, wherein the inner bearing ring is fixedly connected to the output shaft by means of a press-fit connection.

10. The hand-held power tool device as recited in claim 8, wherein the inner bearing ring is configured to act as an axial stop element for the at least one clamping roller.

11. The hand-held power tool device as recited in claim 1, wherein the bearing unit is embodied as a slide bearing, wherein the bearing component includes a slide bearing surface which is directly supported on the output shaft.

12. The hand-held power tool device as recited in claim 11, wherein the bearing component is embodied in one piece with the clamping ring such that the clamping ring is directly supported on the output shaft.

13. The hand-held power tool device as recited in claim 11, wherein the bearing component is fixedly connected to the inner surface of the clamping ring.

14. The hand-held power tool device as recited in claim 11, wherein the bearing component is fixedly connected to the inner surface of the clamping ring by means of a press-fit connection.

15. The hand-held power tool device as recited in claim 1, wherein the bearing unit is configured to support the output shaft at an end oriented toward a drive motor.

16. The hand-held power tool device as recited in claim 1, wherein the at least one catch element is part of a catch device.

17. The hand-held power tool device as recited in claim 1, wherein the catch device is embodied in one piece with a planet carrier of a planetary gear.

18. The hand-held power tool device as recited in claim 1, wherein the at least one clamping roller is arranged between the clamping ring and the output shaft.

19. The hand-held power tool device as recited in claim 18, wherein the at least one clamping roller is directly supported on the output shaft.

20. The hand-held power tool device as recited in claim 1, wherein the at least one clamping roller is arranged adjacent to the bearing component in an axial direction of the output shaft.

21. The hand-held power tool device as recited in claim 1, wherein the at least one clamping ring is at least partially made of a sintered material.

22. The hand-held power tool device as recited in claim 1, further comprising: a housing unit in which the at least one clamping ring is supported with a radial play of less than 0.1 mm.

23. The hand-held power tool device as recited in claim 1, further comprising: a housing unit that is injection-molded around the clamping ring.

24. A hand-held power tool having a hand-held power tool device as recited in claim 1.