U.S. patent application number 11/711707 was filed with the patent office on 2007-09-20 for electrical hand tool device.
This patent application is currently assigned to Metabowerke GmbH. Invention is credited to Mathias Naumann, Guenther Stark.
Application Number | 20070215369 11/711707 |
Document ID | / |
Family ID | 36778084 |
Filed Date | 2007-09-20 |
United States Patent
Application |
20070215369 |
Kind Code |
A1 |
Stark; Guenther ; et
al. |
September 20, 2007 |
Electrical hand tool device
Abstract
The invention concerns an electric hand tool device, in
particular, a percussion drill or a drill hammer, comprising a
spindle (10) that can be driven by a drive motor and cooperates at
one end (12) with a tool support, and a percussion means (24) for
axially moving the spindle (10) in a percussion position, wherein
an adjusting means (42) is provided for adjusting the spindle (10)
between the percussion position and a rotary position, the
adjusting means (42) comprising a switch ring (44) which is
disposed on the spindle (10) and has cam configurations (46,48) on
both end faces thereof, wherein one of the cam configurations (46)
can engage in a corresponding cam configuration (52) which is fixed
to the housing through turning the switch ring (44), and the second
cam configuration (48) can be brought into engagement with a
corresponding cam configuration (60) of a pressure piece (54) which
can be axially moved on the spindle (10), in order to adjust the
percussion means (42) to a percussion position.
Inventors: |
Stark; Guenther;
(Frickenhausen, DE) ; Naumann; Mathias;
(Unterensingen, DE) |
Correspondence
Address: |
DREISS, FUHLENDORF, STEIMLE & BECKER
POSTFACH 10 37 62
D-70032 STUTTGART
omitted
|
Assignee: |
Metabowerke GmbH
Nuertingen
DE
|
Family ID: |
36778084 |
Appl. No.: |
11/711707 |
Filed: |
February 28, 2007 |
Current U.S.
Class: |
173/48 |
Current CPC
Class: |
B25D 2216/0038 20130101;
B25D 2250/045 20130101; B25D 2250/371 20130101; B25D 2250/021
20130101; B25D 11/005 20130101; B25D 11/106 20130101; B25D
2216/0023 20130101 |
Class at
Publication: |
173/48 |
International
Class: |
E02D 7/02 20060101
E02D007/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2006 |
EP |
06 005 591.0 |
Claims
1. An electric hand tool device, a percussion drill, or a drill
hammer, the device comprising: a housing; a drive motor disposed in
said housing; a spindle cooperating with said drive motor and
having an end for engagement with a tool support; percussion means
cooperating with said spindle for axially displacing said spindle
in a percussion mode; a first cam fixed to said housing; a pressure
member having a second cam, said pressure member structured for
axial displacement along said spindle; and a switch ring disposed
on said spindle, said switch ring having a third cam on a first end
face thereof and a fourth cam on a second end face thereof, said
switch ring being structured for turning to bring said third cam
into engagement with said first cam and said fourth cam into
engagement with said second cam, wherein said switch ring is turned
from a rotary position into a percussion position.
2. The electric hand tool device of claim 1, further comprising a
spring cooperating with said pressure member to urge said pressure
member away from said switch ring.
3. The electric hand tool device of claim 1, wherein said spindle
has an axial bearing supporting said pressure member at a side
thereof opposite to said second cam.
4. The electric hand tool device of claim 1, wherein said pressure
member is guided in a cam such that it cannot be rotated relative
to said housing.
5. The electric hand tool device of claim 1, further comprising a
slide switch for rotating said switch ring.
Description
[0001] This application claims Paris Convention priority of EP 06
005 591.0 filed Mar. 18, 2006 the complete disclosure of which is
hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The invention concerns an electrical hand tool device, in
particular, a percussion drill or a drill hammer, comprising a
spindle that can be driven by a drive motor and which cooperates at
one end thereof with its tool support, and with a percussion means
for axially moving the spindle in a percussion position, wherein an
adjusting means is provided for adjusting the spindle between the
percussion position and a rotary position.
[0003] Electric hand tool devices, in particular, percussion drills
and drill hammers which have both a percussion position of the
spindle, in which the spindle performs an axial translatory motion,
and a rotary position, wherein the spindle only executes a rotary
drive, have an adjusting means between the two positions. In
principle, a combined percussion/rotary position may also be
provided, in which the spindle is driven both in a rotary and
percussive fashion.
[0004] A hand drill of this type comprising a means for switching
between the operation modes of drilling and percussion drilling is
disclosed e.g. in EP 0 755 756 B1, in which the drill spindle is
supported against an axial bearing in the rotary drill operating
position, wherein the axial bearing is designed as a rolling
bearing and the adjusting instrument acts on the drill spindle via
this rolling bearing.
[0005] A further embodiment of a corresponding drill is disclosed
e.g. in EP 0 399 714 B1 which concerns a force-operated drill,
comprising a operation mode changing mechanism for changing the
mode of operation of the drill between one mode of operation
without percussion drilling and one mode of operation with
percussive drilling, wherein the mechanism for changing the modes
of operation contains a first rigid and a second elastic
component.
[0006] It is the underlying purpose of the present invention to
present an electric hand tool device, whose adjusting means
provides a maximum adjusting path in order to also provide a
sufficient adjusting path for percussion means with large notch
depression.
SUMMARY OF THE INVENTION
[0007] The invention solves this object with an electric hand tool
device of this type, wherein the adjusting means comprises a switch
ring which is disposed on the spindle and has cam configurations on
both end faces, wherein one of the cam configurations can engage
into a corresponding cam configuration, which is fixed to the
housing, through turning the switch ring, and a second cam
configuration can be brought into engagement with a corresponding
cam configuration of a pressure piece which can be axially moved on
the spindle, in order to adjust the percussion means into a
percussion position.
[0008] The spindle may thereby exercise axial motion due to
engagement of the switch ring in the area of its cam configuration
with a cam configuration which is fixed to the housing. This axial
motion is blocked in the non-engaged state due to mutual abutment
of the cam configurations. A further axial motion is thereby
possible, such that the cam configuration of the pressure piece is
immersed into a second cam configuration of the switch ring,
thereby doubling the axial lift of the spindle.
[0009] In this fashion, a corresponding adjustment means can be
provided with little construction effort even in electric hand tool
devices comprising a percussion means, which require a large axial
spindle lift. The engagement between the cam configuration of the
switch ring and the cam configuration of the housing is thereby
effected by turning the switch ring, such that the curves engage
each other through radial rotation.
[0010] This double engagement between the switch ring and the cam
configuration which is fixed to the housing, and between the
pressure piece and the switch ring provides large axial travel of
the spindle, thereby realizing a switching process, with which two
radial cams of a percussion means can come into engagement with
each other.
[0011] In a particularly advantageous fashion, the pressure piece
may thereby cooperate with a spring which loads the pressure piece
away from the switch ring. I.e. the radial cams of the pressure
piece and the switch ring are not engaged in the normal basic
position. When e.g. the drill of a corresponding percussion drill
is put onto a workpiece to be processed, the spindle is axially
loaded against the spring force and moves in the axial direction
until the radial cams of the percussion means engage with each
other and the cam configurations are immersed into each other
between the switch ring and the pressure piece, such that when the
electric hand tool device is correspondingly switched, percussive
or percussion drilling operation is possible, since the spindle can
be moved in an axial direction.
[0012] When the spindle is no longer axially loaded, e.g. by
removing the electric hand tool device from the workpiece, there is
no remaining percussive motion of the spindle. In this fashion, an
electric hand tool device of this design is much more easy to
hold.
[0013] The side of the pressure piece opposite the cam
configuration may moreover be supported against an axial bearing of
the spindle. The axial bearing serves to guide the spindle in the
rotary position.
[0014] The pressure piece may thereby be preferentially guided in a
crank guidance, such that the pressure piece cannot be rotated but
perform only a purely translatory motion relative to the
housing.
[0015] A slide switch may moreover be provided as a switch for the
adjusting means, which is provided on the outside on a housing of
the electric hand tool device. It may perform e.g., in particular,
a radial sliding motion which rotates the switch ring.
[0016] Further advantages and features of the invention can be
extracted from the other application documents. The invention is
explained in more detail below with reference to the drawing.
BRIEF DESCRIPTION OF THE DRAWING
[0017] FIG. 1 shows a section of an inventive electric hand tool
device in the rotary position; and
[0018] FIG. 2 shows the device in accordance with FIG. 1 in the
percussion position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] FIG. 1 shows part of an electric hand tool device comprising
a spindle 10 with a support 12 for a tool support, wherein the
spindle can be driven via a gear 14 and an electromotor (not shown)
which is connected thereto.
[0020] The spindle is rotatably disposed in a machine housing 16
via bearings 18, 20 and 22.
[0021] The electric hand tool device comprises a percussion
mechanism which is designated in total with reference numeral 24.
The percussion mechanism 24 has substantially two elements, i.e.
the component 26 with a first radial cam 28 and a beater 30 with a
second radial cam 32. The two radial cams 28 and 32 of the
components 26 and 30 face each other.
[0022] The component 26 is thereby pressed onto the spindle 10 and
axially abuts a stop 34. The component 26 rotates with the spindle
and is axially fixed thereto.
[0023] The beater can move axially relative to the spindle 10, but
cannot rotate relative to the housing 16. The beater 30 is guided
in a beater housing 36 which is inserted and fixed in the machine
housing 16.
[0024] A spring 40 is also guided in the beater housing 36 and is
supported on one side against the beater 30 and on its other side
against the beater housing 36, thereby pretensioning it.
[0025] FIG. 1 shows an embodiment, in which the radial cams 28 and
32 are not engaged. In this position, a tool clamped into a
workpiece support performs a rotary motion only without an axial
percussion motion of the spindle 10.
[0026] The radial cams are thereby designed such that at least one
of the radial cams has a control cam which axially projects towards
the other radial cam past the rest of the radial cam. Run-up faces
are moreover provided, which permit sliding of the two radial cams
on top of each other, thereby permitting overlooking of the control
cams provided on one or both radial cams. So-called depressions are
provided between the two control cams.
[0027] When the two radial cams 28 and 32 engage each other through
pressing a tool onto a workpiece to be processed (FIG. 2), the two
radial cams engage with each other. Rotation of the component 26
relative to the beater 30 moves the two radial cams relative to
each other in a radial direction, such that the control cams
cooperate at a certain time, such that the beater 30 is deflected
opposite to the direction of the component 26, thereby loading the
spring 40. This loading of the spring 40 stores energy in the
spring 40. As soon as a depression has been reached on one or both
radial cams through further rotation of the radial cams relative to
each other, the spring 40 is suddenly relaxed, such that the beater
30 is moved by the released energy towards the component 26. The
beater 30 thereby impinges on the component 26 with a predetermined
energy and moves it in an axial direction towards the end 12 of the
spindle 10. Since the component 26 is fixed to the spindle 10 and
abuts, in particular, against the stop 34, the spindle 10 is moved,
together with the component 26, in an axial direction. This
produces a spindle impact, and a percussion drilling operation can
be provided to support drilling.
[0028] In order to permit switching from one percussion position to
a rotary position and vice versa, an adjusting means is provided at
the spindle end opposite to the tool support, which is in total
designated by reference numeral 42. The adjusting means 42
comprises an adjusting instrument (not shown), in particular, a
slide switch that can be displaced in a radial direction and
through which an operator introduces and performs the switching
process. A switch ring 44, which has cam configurations 46 and 48
on both end faces, is radially moved relative to the housing
through actuating the slide switch, wherein the cam configuration
46 can be brought into engagement with a cam configuration on a
component 50 which is fixed to the housing, whose cam configuration
is designated with 52. In FIG. 1, the cam configurations 46 and 50
are out of engagement.
[0029] FIG. 2 shows the cam configurations 46 and 50 of the switch
ring, which are in engagement, and of the component 50 which is
fixed to the housing. The adjusting means 42 moreover comprises a
pressure piece 54 which abuts against the axial bearing 20 via a
spring 56 which supports the spindle 10 during rotary operation.
The spring 56 presses the pressure piece 54 towards the percussion
mechanism 24, such that in the basic position, the percussion
mechanism is in a position in which the radial cams 28 and 32 are
out of engagement.
[0030] When the adjusting ring is placed into the position shown in
FIG. 2 and the spindle 10 end 12 caused to abut a workpiece, the
spring force of the spring 56 can be overcome, such that the
pressure piece 42 is deflected in the direction of arrow 58 to
bring a cam configuration 60, which is disposed on the pressure
piece on its end facing the switch ring 44, into engagement with
the cam configuration 48 of the switch ring 44. This completely
engaged configuration is shown in FIG. 2. The spring 56 is thereby
maximally compressed. In order to obtain proper engagement and
disengagement of the cam configurations 48 and 60, the pressure
piece 54 is guided on a crank guidance, such that it can only
exercise a translatory motion relative to the housing 16. When the
user of such an electric hand tool device lifts the device from a
workpiece to be processed, the pressure on the springs 56 and 40 is
consequently reduced, the springs relax, and the percussive motion
of the spindle is stopped.
[0031] An arrangement as shown in the above figures is advantageous
in that the cam configurations 46 and 52 and the cam configurations
48 and 60 engage each other in such a manner as to provide a
relatively large lift for the spindle 10 (clearly visible in FIGS.
1 and 2), wherein the spindle 10 in FIG. 2 is clearly shifted to
the left in the plane of the drawing. This large axial motion that
the spindle 10 can then perform permits use of a percussion
mechanism with high notch depth or high curvature of the radial
cams 28 and 32.
[0032] The invention increases the lift motion without changing the
operation of a slide switch.
* * * * *