EP3461594A1 - Actuator and gearbox assembly for a driven machine tool - Google Patents

Abstract

The invention relates to an actuator (50) for a gear arrangement (10) of a driven machine tool, which is connectable to an actuating element (60) of the gear arrangement (10) and in the connected state, a switching movement of the actuating element (60) in a displacement of one or more Transmission elements (24, 42, 44) of the transmission assembly (10) is capable of converting, wherein the actuator (50) has two receiving portions (52, 56) for supporting the actuator (50) within the transmission assembly (10). According to the invention, the first receiving portion (52) has a substantially circular recess for receiving a shaft portion of a first gear shaft (30) of the gear assembly (10), and the second receiving portion (56) has a substantially circular recess for receiving a shaft portion of a second gear shaft (20) of the gear assembly (10), wherein at least one of the receiving portions (52, 56) is opened laterally.

Description

The present invention relates to an actuator for a gear assembly of a power tool and a gear assembly for a power tool with a rotating and / or impact driven tool. Such a powered machine tool may in particular comprise a drilling or impact drill or a hammer drill with or without chisel function. As a starting point for the present invention, therefore, some known solutions of this type will be described below.

In known machine tools of this type, especially in rotary hammers, one of a drive unit of the machine tool driven shaft (motor shaft) protrudes with its front end in the gear assembly and drives a intermediate shaft via a drive pinion. For example, the German Offenlegungsschrift discloses DE 196 51 828 A1 Such a hammer drill, the intermediate shaft is arranged parallel to the Bohrwerkzeugachse, but at a distance next to this. The hammer drill further comprises a Luftpolsterschlagwerk and a reciprocating in the direction of Bohrwerkzeugachse reciprocating wobble drive device whose swash bearing or swash plate is mounted on the rotatably driven intermediate shaft.

The term wobble drive device is understood to mean a rotation / translation converter device in which the rotational movement of a drive-side element is converted into a linear translational movement of an output-side element. In this case, a rotation element acts on a wobble element which is referred to below as a wobble bearing in such a way that it is driven to tilt back and forth and can thereby displace a further element into linear translational motion.

For example, as in the DE 196 51 828 A1 discloses a translational movement transmitted to a firing pin of the air cushion impactor, which in turn causes a striking movement of the tool. In addition, the intermediate shaft serves to transmit the drive torque from the driven shaft to the tool. For this purpose, a drive spindle of the machine tool, on which the tool to be rotated can be accommodated, comprises a drill sleeve, which is in engagement with the external toothing of a spur gear of the intermediate shaft seated on the intermediate shaft with an external toothed ring.

The length of the gear assembly is thus significantly influenced by the length and the position of the impact mechanism. So it must be ensured that the swash bearing does not collide with the driven shaft and / or the spur gear of the intermediate shaft. The provided for this purpose distance between the driven shaft, the swash bearing and the spur gear of the intermediate shaft causes the gear assembly takes a total of a relatively large amount of space to complete without this can be fully utilized.

In the DE 10 2008 054 458 A1 Furthermore, a hammer drill is described, which has a drive motor with a motor shaft and a motor spindle connected to the motor shaft. An impact mechanism, which is also operatively connected to the motor shaft, is connected to the tool spindle via a single-stage gearbox. The single-stage gearbox includes a Schlagwerk drive wheel that drives the tool spindle via a ring gear. The motor shaft of the drive motor in turn comprises a motor pinion whose teeth are in operative engagement with an end toothing of the striking mechanism drive wheel.

As a further prior art discloses the US 4,158,313 A a machine tool comprising a drive spindle for the rotary drive of a tool, a coaxial gear ring which can be coupled to the drive spindle, and an intermediate shaft which transmits a drive torque from a driven shaft to the drive spindle able to transmit. The intermediate shaft has for this purpose a gear which is in engagement with the coaxial sprocket of the drive spindle. Furthermore, a gear arrangement is provided which additionally comprises a further countershaft with a gear.

These gear arrangements of the prior art require a comparatively large space, which can not be fully utilized.

Finally, from the publication EP 2 700 477 A1 a gear arrangement is known, in which by the fact that the gear assembly additionally comprises a countershaft with a gear that can be brought into engagement with the coaxial gear rim of the drive spindle or out of engagement therewith, depending on the operating mode of the machine tool, a particularly advantageous utilization of the available space can be provided ,

Although this solution has been well proven in practice, the solution described therein can not be applied to machine tools, for example, have an L-shaped housing, in which in particular the motor axis is not parallel to the transmission axis. In particular rotary hammers have such a housing shape or such an arrangement of gear and motor drive unit.

Furthermore, it has also been found in connection with the used actuator known solutions from the prior art that they require a relatively large amount of space, especially since for the non-rotatable mounting more bolts or rods must be provided inside the housing of the machine tool.

In order now to provide a solution in which the available space can be optimally used within the housing of the machine tool beats the present invention, a transmission arrangement with the features of claim 1 before.

Accordingly, an actuator for a gear assembly of a machine tool is provided which is connectable to an actuator of the gear assembly and in the connected state is able to convert a switching movement of the actuating element into a displacement of one or more transmission elements of the gear assembly, wherein the actuator has two receiving portions for mounting the actuator within the gear assembly has. According to the invention, the first receiving portion has a substantially circular recess for receiving a shaft portion of a first gear shaft of the gear assembly, and the second receiving portion has a substantially circular recess for receiving a shaft portion of a second gear shaft of the gear assembly, wherein at least one of the receiving portions is opened laterally ,

With the aid of the actuating element, the user can, for example, choose between different operating modes of the machine tool. The actuating element may comprise, for example, a rotary knob, the rotational movement causes in a known manner a translational movement of the associated actuator, which in turn shifts the at least one displaceable transmission element in the axial direction. However, alternative embodiments for this purpose are also conceivable, such as an axially displaceable actuating element.

According to the invention, the two receiving areas of the actuator together with the shaft portions received therein bearing points and allow a rotationally fixed arrangement of the actuator within the gear assembly. The actuator according to the invention uses due to its specific configuration, the already existing shaft sections of two transmission shafts of the gear assembly as bearing points, which are arranged substantially parallel to each other. It can the actuator along the two transmission shafts are axially displaced and is at the same time secured against rotation about one of the receiving portions. The provision of a shift rod or a guide pin, as is known from the prior art, thus eliminated, whereby both components and space can be advantageously saved. The specific embodiment with a lateral opening on at least one of the receiving portions also allows easy installation.

Thus, the second receiving portion of the actuator may comprise a laterally open circular recess whose inner diameter substantially corresponds to the outer diameter of the end portion of the intermediate shaft and the lateral opening includes less than 180 degrees, in particular less than 160 degrees, for example, 150 degrees. By the lateral opening, i.e., that no circumferential inner peripheral surface is provided, a simplified assembly can be provided. Thus, the male end portion can be inserted laterally through this opening. In one embodiment, in which the lateral opening includes less than 180 degrees of angle, also a flattening may be provided on the male shaft portion. Now, if the actuator in the mounted state relative to the recorded shaft portion, in particular rotated relative to the flattening, optionally a release movement of the received shaft portion can be prevented from the lateral opening.

Additionally or alternatively, a preferred orientation of the lateral opening in the installed state of the actuator ensure that a rotation of the actuator about the axis of rotation of the countershaft and thus prevents the bearing point formed by the first receiving portion of the actuator. Thus, the lateral opening is oriented such that the recorded shaft portion is engaged behind in the assembled state of the actuator and thus counteracts such unwanted rotational movement.

Thus, it can be provided, in particular, that the lateral opening of at least one of the receiving sections defines a joining direction for receiving the associated shaft section in the receiving section, which is transverse to a tangential direction, which is defined by the respective other receiving section.

This arrangement ensures that in the assembled state, the actuator can not be moved out of the mounted position by external loads or forces, in particular not the corresponding shaft portion of the lateral opening can be moved out by a twisting movement of the actuator again. The tangential direction designates the direction of a tangent around a virtual circle whose center coincides with the central longitudinal axis of the shaft section which is received in the respective other receiving section. Thus, the tangential direction defines the direction in which the actuator could rotate about the respective other receiving area defining a bearing point, if it were not secured by the additional receiving area defining another bearing point. The opening direction transverse thereto defines a direction which is not parallel to the tangential direction. In the mounted state, it is thus ensured that the shaft section accommodated in the laterally open receiving region is engaged behind the rotary element counter to a rotational movement by the actuator.

Furthermore or alternatively, it can be provided that the actuator is fixedly connected in the axial direction with at least one displaceable gear element. In this way, an axial displacement of the at least one axially fixedly connected gear element is achieved by an axial displacement of the actuator.

Furthermore or alternatively it can be provided that the actuator comprises a shift fork, which is formed substantially U-shaped and a bearing leg, a essentially parallel thereto clamping leg and an actuating leg connecting them, wherein the bearing leg has at least one of the receiving portions, wherein the clamping leg between them and the bearing leg is able to tension at least one displaceable transmission element and wherein the actuating leg is connectable by means of a connecting structure with the actuating element of the gear assembly ,

In this case, a plurality of gear elements, for example, a plurality of gears of a gear shaft, be associated with a sliding block and move together with this. The sliding block can be arranged, for example, between the bearing leg and the substantially parallel clamping leg, so that an axial displacement of the actuator has an axial displacement of the sliding block result. In the same way, this of course also applies to individual gears, which can be arranged between the bearing leg and the essentially parallel clamping leg. By a simple displacement of the actuator and arranged between the bearing leg and the substantially parallel clamping leg gear elements, for example, switching between different modes of the gear assembly can be achieved. This results in a comparatively simple switching mimic, which can also save installation space and weight.

Alternatively or additionally, it can be provided that the actuator has a tooth-shaped projection, which can be brought into engagement with a gear element of the gear arrangement in a switching position of the actuator.

This additional function can solve depending on the design of the gear assembly another known from practice problem, namely that in a desired pure bit operation, for example, a drive spindle of the gear assembly (which carries the machining tool) are not only not rotationally driven by the drive unit, but also held non-rotatable should, in particular to ensure a defined orientation of the tool when using a flat chisel. The toothed projection may have at least one or more teeth whose outer contour forms a counter contour to the contour of the toothed circle of the gear element, for example the drive spindle. In this way, a reliable locking of the drive spindle is achieved via the engagement of the mating contour of the toothed attachment with the outer contour of the toothed circle, for example the drive spindle. Alternative desired fixings or couplings of gear elements of the gear arrangement by means of the actuator are of course also conceivable.

According to the invention, a gear arrangement for a driven machine tool with a corresponding actuator with the features described above is also proposed.

According to a further development, the gear assembly may include a driven shaft, a drive spindle for rotationally driving an attached tool, the drive spindle having a coaxial sprocket, and an intermediate shaft capable of transmitting drive torque from the driven shaft to the drive spindle. Furthermore, a countershaft with a coaxial gear and a rotationally fixed associated tumbling drive device is provided, wherein the tumble drive device is capable of converting a rotational movement of the countershaft in a translational movement and is able to transmit to the drive spindle for the striking drive of the tool. The intermediate shaft has a first gear, which is engageable with the coaxial ring gear of the drive spindle, and a second gear, which is engageable with the coaxial gear of the countershaft, wherein the first and second gear in the axial direction relative to the sliding Drive spindle and the countershaft are arranged.

In this specific solution, by providing an intermediate shaft and a countershaft, it is achieved that the entire gear arrangement can be made shorter in the direction of the drilling tool axis since the wobble drive device and the torque transmission to the drive spindle can be spatially separated from one another.

Unlike the solution of EP 2 700 477 A1 The torque is transmitted from the driven shaft to the drive shaft via the intermediate shaft, but not via the countershaft, as described in the prior art. Due to this specific arrangement, in which the torque transmission thus always takes place only via the intermediate shaft and the countershaft is used exclusively for this case by case. To drive the associated tumble drive device to allow the beating drive of the tool, an undesirable asymmetry can be avoided. In addition, the torque transmission via a non-parallel arrangement of driven shaft and output shaft, as may be provided, for example, in an L-shaped rotary hammer, significantly facilitated.

Of course, is not essential to the invention and thus not mandatory that the tool is detachably attachable to the machine tool, i. The invention can also be implemented in a machine tool, in which the tool is not detachable, but firmly attached to the machine tool.

The driven shaft is driven by a drive unit, such as an electric motor or a pneumatic drive unit, and transmits the drive torque in a conventional manner to the intermediate shaft of the gear assembly. The drive spindle is used for the rotary drive of a tool which can be accommodated on the machine tool, wherein the intermediate shaft can be brought into engagement with the coaxial toothed ring of the drive spindle via a first gearwheel and, via this, transmit the drive torque from the driven shaft to the drive spindle can. Due to the fact that this engagement is also releasable, ie, the first gear of the intermediate shaft can also be disengaged from the coaxial sprocket of the drive spindle, an operation of the machine tool can be achieved in which no torque is transmitted, as for example when chiseling with a flat chisel is desired.

In addition, the torque can be transmitted to the countershaft via the second gear of the intermediate shaft, which is engageable with the coaxial gear of the countershaft, whereby the rotatably connected tumbling drive device is driven. This can convert a rotational movement of the countershaft into a translational movement and to transmit this translational movement to the drive spindle for the striking drive of the tool. Both the first and the second gear of the intermediate shaft are arranged in the axial direction (relative to the longitudinal axis of the intermediate shaft) relatively displaceable to the drive spindle and the countershaft.

According to one embodiment of the invention can be provided that the intermediate shaft comprises a sliding block which is slidably disposed on the intermediate shaft in the axial direction between at least two positions and having the first gear and the second gear. In this embodiment, therefore, the first gear and the second gear of the intermediate shaft are displaced axially relative to the intermediate shaft and move accordingly also relative to the drive spindle and the countershaft as a result of this sliding movement. The displacement may be enabled between two maximum positions, that is, between at least two positions. Of course, however, one or more intermediate position (s) can be selected between these maximum positions, as will be described in more detail later.

In conjunction with the actuator according to the invention can be a shift between different by displacement of the first gear and / or the second gear Operating modes of the machine tool can be achieved. Thus, the two gears of the intermediate shaft are not only used for torque transmission, but also for switching between different operating modes of the machine tool.

A first mode in which the coaxial ring gear of the drive spindle is in engagement with the first gear of the intermediate shaft, and the second gear of the intermediate shaft is out of engagement with the coaxial gear of the countershaft, describes a mode in which the drive spindle is only driven in rotation (purer drilling).

In a second operating mode of the machine tool, the first gear and the second gear of the intermediate shaft are respectively in engagement with the corresponding coaxial sprocket of the drive spindle and the coaxial gear of the countershaft. In this mode, the drive spindle is thus driven not only rotating but also hitting. This corresponds to the impact drilling operation of the machine tool.

In a third mode of operation, the first gear of the intermediate shaft may be disengaged from the coaxial sprocket of the drive spindle while the second gear is in engagement with the co-axial gear of the countershaft. In this mode, therefore, no more torque is transmitted to the drive spindle but only a translation generated by the wobble drive device for the striking drive of the tool (chisel operation).

With the help of the actuating element of the machine tool, the user can choose between the different operating modes of the machine tool. The actuating element may comprise, for example, a rotary knob, the rotational movement of which in a known manner causes a translational movement of the associated actuator, which in turn displaces the sliding block in the axial direction. However, alternative embodiments for this purpose are also conceivable, such as an axially displaceable actuating element.

The fact that the two gears of the intermediate shaft are assigned to the sliding block and move together with this, can be achieved by a simple displacement of the sliding block switching between the three modes described. This results in a comparatively simple switching mimic, which can also save installation space and weight.

In particular, it can be provided that the actuator is firmly connected in the axial direction with the sliding block.

Furthermore, it can be provided that the actuator is further rotatably disposed within the gear assembly and in particular has a toothed projection which is engageable in a switching position of the actuator in locking engagement with the coaxial sprocket of the drive spindle.

This additional function solves another known from practice problem, namely that in the pure chisel operation, the drive spindle are not only not rotationally driven by the drive unit, but also to be held non-rotatable to ensure a defined orientation of the tool especially when using a flat chisel. The toothed projection may have at least one or more teeth whose outer contour forms a counter contour to the contour of the toothed circle of the drive spindle. In this way, a reliable locking of the drive spindle is achieved via the engagement of the mating contour of the toothed attachment with the outer contour of the toothed circle of the drive spindle.

In this case, the actuator may in particular be arranged on the sliding block such that an intermediate position in which the projection of the actuator is not yet in Engagement with the coaxial sprocket of the drive spindle is fixed and this rotatably fixed, but in which no more torque transmission from the intermediate shaft to the drive spindle, since the first gear is already brought out of engagement with the coaxial sprocket of the drive spindle, be provided. This intermediate position allows the setting of, for example, a flat chisel in its desired orientation. Then, if the actuator is moved further and the toothed projection engages with the coaxial sprocket of the drive spindle, the flat chisel remains in its desired orientation, since now the drive spindle is rotatably held by the likewise rotatably mounted actuator, whereby a defined machining with a flat chisel allows becomes.

As already stated above, the actuator for rotationally fixed arrangement within the gear assembly on two receiving portions. In the present development, the first receiving area for receiving an end portion of the countershaft and the second receiving area for receiving an end portion of the intermediate shaft serve. Thus, here also form the two receiving areas of the actuator bearing points and allow a rotationally fixed arrangement of the actuator within the gear assembly. For this non-rotatable arrangement required components are used anyway, which in turn is space and weight saving.

In particular, it can be provided that the first receiving portion of the actuator comprises a circular recess whose inner diameter substantially corresponds to the outer diameter of the end portion of the countershaft. The recess is designed as a through hole to allow axial displacement of the actuator with respect to the intermediate shaft.

Regardless of this specific embodiment of the first receiving portion, the second receiving portion of the actuator may comprise a laterally open circular recess whose inner diameter substantially to the outer diameter corresponds to the end portion of the intermediate shaft and whose lateral opening includes less than 180 degrees, in particular less than 160 degrees, for example, 150 degrees of angle. Also, this laterally open circular recess may be designed as a through-hole to provide the axial displacement of the actuator in a simple manner. By the lateral opening, ie, in that no circumferential inner peripheral surface is provided, a simplified assembly can be provided. Thus, the male end portion can be inserted laterally through this opening. In a configuration in which the lateral opening includes less than 180 degrees of angle, also a flattening may be provided on the male end portion. Now, if the actuator in the mounted state relative to the received end portion, in particular rotated relative to the flattening, if appropriate, a release movement of the received end portion of the lateral opening can be prevented.

Additionally or alternatively, a preferred orientation of the lateral opening in the installed state of the actuator ensure that a rotation of the actuator about the axis of rotation of the countershaft and thus prevents the bearing point formed by the first receiving portion of the actuator. Thus, the lateral opening is oriented such that the end portion of the intermediate shaft is engaged behind in the mounted state of the actuator and thus counteracts such unwanted rotational movement.

Furthermore, it can be provided that the gear arrangement further comprises a Luftpolsterschlagwerk, which is connected to the drive spindle. In this case, the air cushion impact mechanism may be partially formed integrally with the drive spindle or formed separately and be firmly connected in the mounted state with this. Such an air cushion percussion device may comprise a percussion piston, an anvil and an exciter sleeve and a drill sleeve in a conventional manner, wherein the exciter sleeve can be slidably received within the drill sleeve and with this to be able to form a space accommodating the air cushion. In known manner, within the space by means of the exciter sleeve of the percussion piston can be set in a reciprocating motion, which is transmitted via the striker on a recorded in the tool holder of the drive spindle tool. One or more parts of the percussion mechanism can be integrally formed with the drive spindle or firmly connected to it.

The driven shaft can, as already mentioned, be arranged at an angle, in particular at a right angle to the drive spindle. As a result, a compact rotary hammer can be provided with an L-shaped housing with optimum housing space utilization.

Furthermore, it can be provided that the intermediate shaft has a rotatably connected thereto ring gear, which is in meshing engagement with a pinion of the driven shaft. This allows a right angle arrangement of intermediate shaft and driven shaft.

Finally, the present invention also relates to a machine tool having a housing, in particular in an L-shaped construction, in which the housing may comprise at least a first housing part with a first longitudinal axis and a second housing with a second longitudinal axis, and wherein the first and second longitudinal axis are not arranged parallel to each other, and with a gear arrangement having one or more of the features described above.

Further features and advantages of the invention will become apparent from the following description of an embodiment of the invention and from the dependent claims.

The invention is described below with reference to the accompanying figures. The figures show several features of the invention in combination together. Of course, however, the skilled person is able to view them detached from one another and, if appropriate, to combine them into further useful sub-combinations without having to be inventive in their work.

Figur 1

eine erfindungsgemäße Getriebeanordnung in einer Seitenansicht;

Figur 2

eine Vorderansicht auf die Getriebeanordnung gemäß Figur 1;

Figur 3

eine schematische Darstellung der erfindungsgemäßen Getriebeanordnung der Figuren 1 und 2 in einer von mehreren unterschiedlichen Betriebsstellungen;

Figur 4

einen Schaltblock der Getriebeanordnung gemäß Figur 2 mit einem erfindungsgemäßen Stellglied;

Figur 5

die erfindungsgemäße Getriebeanordnung gemäß Figur 1 in einer isometrischen Darstellung; und

Figur 6

eine Draufsicht auf einen Teil der Getriebeanordnung gemäß den Figuren 1 und 5.

They show schematically:

FIG. 1

a gear arrangement according to the invention in a side view;

FIG. 2

a front view of the transmission assembly according to FIG. 1 ;

FIG. 3

a schematic representation of the transmission arrangement of the invention Figures 1 and 2 in one of several different operating positions;

FIG. 4

a switching block of the gear assembly according to FIG. 2 with an actuator according to the invention;

FIG. 5

the transmission arrangement according to the invention FIG. 1 in an isometric view; and

FIG. 6

a plan view of a part of the transmission arrangement according to the FIGS. 1 and 5 ,

The FIG. 1 shows a transmission assembly according to the invention, which is generally designated by the reference numeral 10. The gear arrangement 10 comprises a driven shaft 12, which is driven by a drive unit designed as an electric motor M, a drive spindle 14 and an intermediate shaft 20 and a countershaft 30 designed as a wobble drive shaft. The drive spindle 14 has its free end remote from the driven shaft 12 a tool holder (not shown) for receiving a tool, such as a Drill or chisel, on. Furthermore, the drive spindle 14 comprises a drill sleeve 18 which engages in sections thereof. The drive spindle 14 extends in a longitudinal direction L, which coincides with a tool axis (Bohrwerkzeugachse).

Parallel to the drive spindle 14 extend the intermediate shaft 20 and the wobble drive shaft 30. The respective axes of rotation are arranged parallel to the longitudinal direction L and not designated.

The intermediate shaft 20 is used in the present transmission assembly 10 for transmitting a drive torque from the driven shaft 12 to the drive spindle 14. For this purpose, the intermediate shaft 20 has a ring gear 22 with a frontal toothing 22a, which is in engagement with an external toothing 12a of the driven shaft 12 , The drive torque of the electric motor M is transmitted via the external teeth 12a and the teeth 22a of the ring gear 22 to the intermediate shaft 20 (see also FIG. 3 ). The intermediate shaft 20 further includes a switching block or sliding block 44 which engages positively in a splined toothing 46 on the outer circumference of the intermediate shaft 20 and thus slidably along the intermediate shaft 20, but rotatably mounted thereon. In this case, the direction of displacement of the sliding block 44 in the FIGS. 1 and 3 indicated by the double arrow S. In the schematic representation of FIG. 3 the spline toothing 46 is shown over the entire length of the intermediate shaft 20. In fact, this can, however, such as in the FIG. 6 shown, extend only over a limited portion of the intermediate shaft 20.

The sliding block 44 has a first ring gear 24, which is in engagement with a ring gear 28 which is rotatably connected to the drive spindle 14. In this way, the drive torque is transmitted from the intermediate shaft 20 via the first ring gear 24 of the sliding block 44 to the ring gear 28 of the drive spindle 14.

Characterized in that the sliding block 44 along the longitudinal axis of the intermediate shaft 20, which coincides with its axis of rotation and thus parallel to the longitudinal axis L of the drive spindle 14 is slidably formed, the first ring gear 24 can be brought into or out of engagement with the ring gear 28 of the drive spindle 14 become.

The sliding block 44 further includes a second sprocket 42 which can be brought into engagement with a sprocket 26 of the wobble drive shaft 30 depending on the position of the sliding block 44. Thus, in a corresponding operating position of the sliding block 44, the torque of the intermediate shaft 20 are not only used to drive the drive spindle 14 by this is transmitted to the ring gear 28 of the drive spindle 14 via the first ring gear 24, but also to drive the Taumeltriebwelle 30 by the torque is transmitted via the second ring gear 42 to the ring gear 26 of the wobble drive shaft 30.

In addition, the sliding block 44 comprises a bearing portion 74, to which reference is made in more detail in connection with a shift fork 50 surrounding these components.

On the wobble drive shaft 30, which extends parallel to the intermediate shaft 20 and is arranged at a predetermined distance from this (see also FIG. 2 ), a tumble drive device 32 is arranged. This includes a wobble bearing 34 which is rotatably connected to the wobble drive shaft 30, and a connecting means 36 which is received in the manner of a ball joint in a corresponding receptacle 38a of a reciprocating piston or a exciter sleeve 38. The wobble drive device 32 is used in a known manner to a rotational movement of the wobble drive shaft 30 in a translational movement T (see. FIG. 3 ) and possibly to transfer these via an air spring on the exciter sleeve 38.

The gear assembly 10 finally includes a striking mechanism 40, which may be formed, for example, as a Luftpolsterschlagwerk and a percussion piston, an anvil, and the exciter sleeve 38 and a drill sleeve may include, the exciter sleeve 38 may be slidably received within the drill sleeve and with this one the air cushion can take up receiving space. In a known manner, within this space receiving the air cushion by means of the exciter sleeve 38 of the percussion piston is set in a reciprocating motion, which is transmitted via the striker (not shown) to a recorded in the tool holder of the drive spindle 14 tool. Consequently, if the wobble drive shaft 30 is driven via the ring gear 28, the wobble drive device 32 converts this rotational movement into a translational movement T, which generates a striking movement of the tool received with the aid of the percussion mechanism 40.

Below is on the different modes of the transmission assembly according to the invention with reference to in particular the FIG. 3 To be received. The FIG. 3 shows in particular an operating position in which the sliding block 44 is shown in an operating position in which the first ring gear 24 is in engagement with the ring gear 28 of the drive spindle 14, while the second ring gear 42 is in rotationally fixed engagement with the ring gear 26 of the wobble drive shaft 30 , This operating position shows a beating drilling operation (hammer drilling position), in which the tool executes a rotational movement on the one hand and, secondly, in addition to the rotational movement, also experiences a striking movement (hammer drilling operation).

Will now the switching block 44 from in the FIG. 3 shown position along the longitudinal axis of the intermediate shaft 20 (indicated by the double arrow S in the FIG. 3 ) is shifted to the right, the second ring gear 42 can be disengaged from the ring gear 26 of the wobble drive shaft 30. In this position, therefore, the wobble drive shaft 30 is no longer driven in rotation; the tumble drive device 32 is therefore stationary, so that no more translational movement is transmitted to the drive spindle 14. This operating position thus describes an operating mode in which the drive spindle 14 is driven in rotation only by means of the intermediate shaft 20 and the first ring gear 24 of the sliding block 44 (drilling position), so that a recorded in the tool holder tool is driven only rotationally (drilling operation).

Starting from the in FIG. 3 shown operating position, the sliding block 44, however, are also moved in the direction S to the left, so that the first ring gear 24 out of engagement with the ring gear 28 of the drive spindle 14 passes. In this third operating position, the second ring gear 42 remains in rotational engagement 26 with the wobble drive shaft 30, whereby the wobble drive device 32 is further driven and transmits a translational movement T to the drive spindle 14 (bit position). In this position, a recorded on the tool holder tool thus undergoes only a purely beating motion, as no torque is transmitted to the drive spindle 14 via the ring gear 28 (hammer operation or chisel operation).

In order to enable a simple switching and at the same time a particularly simple and inexpensive construction, an actuator 50 designed as a shift fork 50 is additionally provided, which is displaceably mounted on the wobble drive shaft 30 at a first bearing point 52 (first receiving section of the actuator). Characterized in that the shift fork 50 is slidably mounted on the intermediate shaft 20 in a second bearing point 56 (second receiving portion of the actuator), an undesirable pivotal movement of the shift fork 50 about the first bearing point 52 due to an undesirable rotational movement of the ring gear 28 is reliably prevented. Like in the FIG. 4 it can also be seen, the second bearing point 56 is provided with a lateral opening 58 which includes less than 180 degrees of angle. As a result, a simple assembly and at the same time a secure storage of the shift fork 50 is ensured.

Like in the FIG. 4 as well as in the following FIGS. 5 and 6 can be clearly seen, the lateral opening 58 of the second receiving portion 56 is oriented such that a joining direction F does not coincide with a tangential direction T. The joining direction defines the direction in which the male shaft section (bearing section 72) of the intermediate shaft is inserted laterally into the second receiving region 56. The tangential direction T, however, defines the direction of a straight line which runs through the central longitudinal axis of the intermediate shaft 20 and at the same time is tangent to a virtual circular path K whose center coincides with the central longitudinal axis of the wobble drive shaft 30.

The fact that the joining direction F does not coincide with the tangential direction T, the intermediate shaft 20 can not be undesirably rotated out of the receiving portion 56 at a initiated in the shift fork 50 rotational movement. Instead, the shift fork 50 engages behind the bearing portion 74 of the intermediate shaft 20 and allows together with the laterally closed exception section 52 (as another bearing point) a rotationally fixed mounting of the shift fork 50 relative to the two shafts 20 and 30, without requiring additional components, as in the state of Technology necessary, must be provided.

Like in the FIG. 2 can be clearly seen, a control element 60 is further provided which is formed in the form of a rotary handle. If the user now rotates on the rotary handle 60, which is mounted on the outside of the machine tool housing (not shown) in the installed state and projects through it, the rotary movement of the rotary handle 60 is converted in a known manner via a positioning wire 62 into a translatory movement (operating movement B). the shift fork 50 and connected thereto the shift block 44 converted. For this purpose, the jumper wire 62 is connected in a known manner via the support structures 70, 72 with the shift fork 50 and guided on this.

The shift fork 50 is formed in a plan view substantially U-shaped (see also FIG. 6 ). It can, as shown, comprise a bearing leg 64, a substantially parallel clamping leg 66 and an actuating leg 68 connecting them. On the bearing leg 64, the two substantially as a circular or circular segment-shaped through holes are formed, which the receiving portions 52, 56 for the form respective shaft portions of the intermediate shaft 20 and the wobble drive shaft 30.

Between the bearing leg 64 and the clamping leg 66 of the shift fork, the components of the actuator 44 are arranged, namely the two gears 24 and 42 and the bearing portion 74, which are mounted axially displaceable together with the shift fork on the spline 46 of the intermediate shaft 20.

In order also to avoid undesired rotation of the drive spindle 14 in hammer operation or chisel operation, the shift fork 50 at its bearing leg 64 (see also FIG. 4 ) has a toothed portion 54 which corresponds in its toothing with the external toothing of the ring gear 28. Thus, if the sliding block 44 is moved to the left for hammer operation or bit operation, the shift fork 50 can be brought into rotationally fixed engagement with the ring gear 28 of the drive spindle 14.

Claims (12)

Actuator (50) for a gear arrangement (10) of a driven machine tool, which is connectable to an actuating element (60) of the gear arrangement (10) and in the connected state, a switching movement of the actuating element (60) in a displacement of one or more transmission elements (24, 42, 44) of the gear assembly (10), the actuator (50) having two receiving portions (52, 56) for supporting the actuator (50) within the gear assembly (10),
characterized in that the first receiving portion (52) has a substantially circular recess for receiving a shaft portion of a first gear shaft (30) of the gear assembly (10), and in that the second receiving portion (56) has a substantially circular recess for receiving a shaft portion of a second transmission shaft (20) of the gear arrangement (10), wherein at least one of the receiving portions (52, 56) is opened laterally. Actuator (50) according to claim 1,
characterized in that the lateral opening (58) of at least one of the receiving portions (56) defines a joining direction (F) for receiving the associated shaft portion in the receiving portion which is transverse to a tangential direction (T) defined by the respective other receiving portion , Actuator (50) according to claim 1 or 2
characterized in that the actuator (50) axially fixed to at least one sliding transmission element (24, 42, 44) is connected. Actuator (50) according to one of the preceding claims,
characterized in that the actuator comprises a shift fork (50) which is formed substantially U-shaped and a bearing leg (64), a substantially parallel thereto clamping leg (66) and an actuating leg connecting them (68), wherein the bearing leg (64) at least one of the receiving portions (52, 56), wherein the clamping leg (66) between them and the bearing leg (64) at least one displaceable gear element (24, 42, 44) to tension and wherein the actuating limb (68) by means of a connection structure (70, 72) with the actuating element (60) of the gear arrangement (10) is connectable. Actuator (50) according to one of the preceding claims,
characterized in that the actuator (50) has a tooth-shaped projection (54) which is engageable in a switching position of the actuator (50) in engagement with a transmission element (28) of the gear arrangement (10). Gear arrangement (10) for a power tool with an actuator (50) according to one of the preceding claims. Gear arrangement (10) according to claim 6 for a power tool with a rotating and / or impact driven tool, which is detachably attachable to the machine tool, further comprising: - a driven shaft (12); - A drive spindle (14) for the rotary drive of a releasably mounted tool, wherein the drive spindle (14) has a coaxial sprocket (28), and - An intermediate shaft (20) which is capable of transmitting a driving torque from the driven shaft (12) on the drive spindle (14); and - A countershaft (30) with a coaxial gear (26) and a rotatably connected wobble drive device (32), wherein the wobble drive device (32) converting a rotational movement of the countershaft (30) into a translational movement (T) and transmitting it to the drive spindle (14) for the impacting drive of the tool, characterized in that the intermediate shaft (20) has a first gear (24) engageable with the coaxial sprocket (28) of the drive spindle (14) and a second gear (42) engaged with the coaxial gear (26) the countershaft (30) can be brought,
wherein the first and the second gear (24, 42) in the axial direction are relatively displaceable relative to the drive spindle (14) and the countershaft (30) are arranged. Gear arrangement (10) according to claim 7,
characterized in that the intermediate shaft (20) comprises a sliding block (44) which is displaceably arranged on the intermediate shaft (20) in the axial direction between at least two positions and the first gear (24) and the second gear (42). Gear arrangement (10) according to one of the preceding claims 7 to 8, characterized in that it further comprises a Luftpolsterschlagwerk (40) which is fixedly connected to the drive spindle (14). Gear arrangement (10) according to one of the preceding claims 7 to 9, characterized in that the driven shaft (12) is arranged at an angle, in particular at a right angle, to the drive spindle (14). Gear arrangement (10) according to one of the preceding claims 7 to 10, characterized in that the intermediate shaft (20) has a non-rotatably connected therewith ring gear, which is in meshing engagement with a pinion of the driven shaft (12). Machine tool with a housing, in particular in an L-shaped construction, in which the housing comprises at least a first housing part with a first longitudinal axis and a second housing part with a second longitudinal axis and the first and second longitudinal axes are not arranged parallel to one another, and with a gear arrangement ( 10) according to any one of claims 6 to 11.

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