U.S. patent application number 10/214844 was filed with the patent office on 2003-02-20 for power tool with optical control.
Invention is credited to Braun, Sigmund, Kress, Christof, Rudolf, Boris.
Application Number | 20030034164 10/214844 |
Document ID | / |
Family ID | 7696257 |
Filed Date | 2003-02-20 |
United States Patent
Application |
20030034164 |
Kind Code |
A1 |
Rudolf, Boris ; et
al. |
February 20, 2003 |
Power tool with optical control
Abstract
An optical control is disclosed which is particularly suitable
for application as a switching device, regulating device or sensor
device for a power tool. At least two optical waveguides are
provided one of which being configured as a transmitting waveguide
is coupled to a light source, a second one of which being
configured as a receiving waveguide cooperating therewith is
coupled to an evaluation circuitry. Both waveguides cooperate with
a control element that is movable at least between two positions in
which light signals of different magnitude are transmitted from the
transmitting waveguide into the receiving waveguide.
Inventors: |
Rudolf, Boris; (Stuttgart,
DE) ; Braun, Sigmund; (Kusterdingen, DE) ;
Kress, Christof; (Deizisau, DE) |
Correspondence
Address: |
ST. ONGE STEWARD JOHNSTON & REENS, LLC
986 BEDFORD STREET
STAMFORD
CT
06905-5619
US
|
Family ID: |
7696257 |
Appl. No.: |
10/214844 |
Filed: |
August 8, 2002 |
Current U.S.
Class: |
173/2 |
Current CPC
Class: |
G02B 6/3508 20130101;
G02B 6/3552 20130101; G02B 6/3574 20130101; G02B 6/266 20130101;
G02B 6/3594 20130101; G02B 6/353 20130101 |
Class at
Publication: |
173/2 |
International
Class: |
B25D 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 16, 2001 |
DE |
101 41 161.8 |
Claims
What is claimed is:
1. A power tool comprising a housing; a motor received in said
housing for driving a tool; a clamping lever for clamping a tool,
said clamping lever being movable between a clamping position and a
loose position; an optical control device for controlling the
position of said clamping lever, wherein said optical control
device comprises a light source; at least two optical waveguides,
at least a first one of which being configured as a transmitting
waveguide being coupled to said light source and cooperating with a
second one of said optical waveguides, said second optical
waveguide being configured as a receiving waveguide; a control
element being movable between at least two positions for
controlling light input from said transmitting waveguide into said
receiving waveguide; and an evaluation circuitry coupled to said
receiving waveguide for evaluating the light received by said
receiving waveguide.
2. The power tool of claim 1, wherein said optical control device
is configured as a switch allowing an activation of the motor only
when the clamping lever is in the clamping position.
3. A power tool comprising a housing; a motor received within said
housing for driving a tool; a mechanical control means movable into
at least two positions for controlling the operation of the power
tool; an optical control device being coupled to said mechanical
control means for monitoring said mechanical control means to
thereby control the operation of the power tool depending on the
position of said mechanical control means, wherein said optical
control device comprises a light source; at least two optical
waveguides, at least a first one of which being configured as a
transmitting waveguide being coupled to said light source and
cooperating with a second one of said optical waveguides, said
second optical waveguide being configured as a receiving waveguide;
a control element being movable between at least two positions for
controlling light input from said transmitting waveguide into said
receiving waveguide; and an evaluation circuitry coupled to said
receiving waveguide for evaluating the light received by said
receiving waveguide.
4. The power tool of claim 3, wherein said mechanical control means
is configured as said control element.
5. A power tool comprising a housing; a motor received within said
housing for driving a tool; at least one receptacle supported by
said housing for receiving a detachable attachment part; and at
least one optical control device for controlling, whether said
attachment part is attached to said receptacle or not.
6. The power tool of claim 5, wherein said optical control device
comprises a light source; at least two optical waveguides, at least
a first one of which being configured as a transmitting waveguide
being coupled to said light source and cooperating with a second
one of said optical waveguides, said second optical waveguide being
configured as a receiving waveguide; a control element being
movable between at least two positions for controlling light input
from said transmitting waveguide into said receiving waveguide; and
an evaluation circuitry coupled to said receiving waveguide for
evaluating the light received by said receiving waveguide.
7. A power tool comprising a housing; a motor received within said
housing for driving a tool; at least one optical control device for
controlling the activation of said motor, wherein said optical
control device comprises a light source; at least two optical
waveguides, at least a first one of which being configured as a
transmitting waveguide being coupled to said light source and
cooperating with a second one of said optical waveguides, said
second optical waveguide being configured as a receiving waveguide;
a control element being movable between at least two positions for
controlling light input from said transmitting waveguide into said
receiving waveguide; and an evaluation circuitry coupled to said
receiving waveguide for evaluating the light received by said
receiving waveguide.
8. A power tool having at least one optical control device, said
optical control device comprising a light source; at least two
optical waveguides, at least a first one of which being configured
as a transmitting waveguide being coupled to said light source and
cooperating with a second one of said optical waveguides, said
second optical waveguide being configured as a receiving waveguide;
a control element being movable between at least two positions for
controlling light input from said transmitting waveguide into said
receiving waveguide; and an evaluation circuitry coupled to said
receiving waveguide for evaluating the light received by said
receiving waveguide.
9. The power tool of claim 8, further comprising a pistol shaped
housing, wherein said control element is activatable by means of a
key arranged on said housing.
10. The power tool of claim 7, wherein at least one of said optical
waveguides is integrated into a wall of said housing.
11. The power tool of claim 8, further comprising a housing, within
which said control element is received integrally molded with at
least part of said housing by means of
two-component-technology.
12. The power tool of claim 8, wherein each of said transmitting
and receiving waveguides has an end, wherein said ends of said
transmitting and receiving waveguides are both received in a common
unit that is protected against dust contamination from the
outside.
13. The power tool of claim 8, wherein said transmitting waveguide
at a first end thereof is coupled with said light source, wherein
said receiving waveguide at a first end thereof is coupled with
said evaluation circuitry, and wherein a second end of said
transmitting waveguide is arranged at a distance from a second end
of said receiving waveguide.
14. The power tool of claim 13, wherein said control element is
configured as an elastic form part surrounding said second ends of
said optical waveguides.
15. The power tool of claim 14, wherein said elastic form part is
configured as a sleeve that is elastically deformable in a region
extending between said second ends for blocking any light signals
input into said receiving waveguide.
16. The power tool of claim 15, wherein said elastic form part
comprises a thickening that is arranged between said second ends
and that is elastically deformable.
17. The power tool of claim 13, wherein said second ends of said
optical waveguides are aligned with each other for transmitting
light from said transmitting waveguide into said receiving, and
wherein said control element engages one of said second ends for
moving same relative to the other one of said second ends.
18. The power tool of claim 13, wherein said second ends of said
optical waveguides are aligned with each other for transmitting
light from the transmitting waveguide into the receiving waveguide,
and wherein said control element comprises a section that is
movable into a space between said second ends.
19. The power tool of claim 18, wherein said control element is
configured as a spring element, the movable section of which
comprises a light passing opening allowing the passing of light
from said transmitting waveguide into said receiving waveguide when
being aligned with said second ends.
20. The power tool of claim 13, wherein said control element is
covered by an elastic touch pad.
21. The power tool of claim 13, wherein said optical control device
is configured as an optically controlled switch.
22. The power tool of claim 13, wherein said optical control device
is configured as an optically controlled non-locking key.
23. The power tool of claim 13, wherein said optical waveguides are
movable between a position in which said second ends are aligned
with each other, and between a position in which said second ends
are not aligned with each other.
24. The power tool of claim 23, wherein said control element is
configured as a slider which is slidable between an idle position
in which said second ends of said optical waveguides are not
aligned with each other, and between an operative position in which
said second ends are aligned with each other for transmitting light
into said receiving waveguide.
25. The power tool of claim 24, wherein said slider is lockable in
said operative position and is biased toward said idle
position.
26. The power tool of claim 23, wherein one second end of a first
one of said optical waveguides is biased into a direction
substantially transversely to said first optical waveguide, and
wherein said control element is arranged for engaging said one
second end for moving same between said positions.
27. The power tool of claim 24, wherein said slider is covered by
an elastic touch pad to which it is firmly connected, said elastic
touch pad having a material tension which elastically biases said
slider into one of said idle and said operative positions.
28. The power tool of claim 8, wherein said transmitting waveguide
comprises at least one radial light emitting opening for radial
emission of light, said radial light emitting opening cooperating
with a light receiving opening of said receiving waveguide.
29. The power tool of claim 28, wherein said transmitting and
receiving waveguides are at least partially configured as annular
optical waveguides that are held at a distance from each other, and
wherein said control element is configured as a switching ring
arranged for engaging at least one of said waveguides for moving
same with respect to the other one of said waveguides.
30. The power tool of claim 29, wherein said transmitting and
receiving waveguides are held within an annular tube at a distance
from each other, wherein a transmission of light into the receiving
waveguide is impeded in an idle position, and wherein said
switching ring is movable relative to the tube into an activated
position, in which said tube is deformed to thereby input light
from the transmitting waveguide into the receiving waveguide.
31. The power tool of claim 8, wherein said transmitting and the
receiving waveguides are at least partially configured as annular
optical waveguides that are held at a distance from each other,
wherein said control element is configured as a switching ring that
allows to input light from the transmitting waveguide into at least
one selected region of said receiving waveguide when being in an
operative position.
32. The power tool of claim 13, wherein said control element is
configured as a rotary slide being coupled with one of said second
ends of said optical waveguides for moving same between both
positions.
33. The power tool of claim 32, wherein said control element is
configured as a switching ring which is rotatable between an idle
position and an operative position.
34. The power tool of claim 13, wherein said second ends of said
optical waveguides are not aligned with each other, and wherein
said control element comprises means for inputting light from said
transmitting waveguide into said receiving waveguide, when being in
at least one of said at least two positions of said control
element.
35. The power tool of claim 34, wherein said means for inputting
comprises a deflector for angularly deflecting light.
36. The power tool of claim 35, wherein said deflector comprises at
least one reflecting surface.
37. The power tool of claim 35, wherein said deflector comprises a
prism.
38. The power tool of claim 35, wherein said deflector cooperates
with said second ends for redirecting light from said transmitting
waveguide to an optical display.
39. The power tool of claim 34, wherein said control element
comprises a rotary slide supporting said means for inputting.
40. The power tool of claim 39, wherein said rotary slide is
configured as a switching ring which biased into the direction of
an idle position.
41. The power tool of claim 40, wherein said switching ring is
elastically biased into a middle idle position.
42. The power tool of claim 40, further comprising a deflector for
redirecting light from said transmitting waveguide toward a display
surface, when being in said idle position, for optically signaling
the idle position.
43. The power tool of claim 41, wherein said switching ring is
movable from said idle position in a first direction of rotation
into a first operative position in which light from said
transmitting waveguide is input into said receiving waveguide, and
is movable in a second direction of rotation into a second
operative position in which also light from said transmitting
waveguide is input into said receiving waveguide.
44. The power tool of claim 39, further comprising a housing having
at least one housing opening, wherein said rotary slide comprises
an elastic touch pad that is received within said housing
opening.
45. The power tool of claim 44, wherein said means for inputting is
received on said elastic touch pad.
46. The power tool of claim 44, wherein said touch pad has an
elasticity, whereby said control element is biased into one of an
idle position and an activated position.
47. The power tool of claim 36, wherein said means for inputting
comprises a mirror that is movable into a position for transmitting
light from the transmitting waveguide into said receiving
waveguide.
48. The power tool of claim 47, wherein said mirror comprises a
spring which is clamped at one end thereof and which receives a
mirror surface at the other end thereof, the mirror surface being
movable against the action of a force excerted by the spring.
49. The power tool of claim 8, wherein said control element is
movable continuously between a first position and a second
position, wherein more light is input into said receiving waveguide
when being in said second position than when being in said first
position.
50. The power tool of claim 48, wherein said spring element rests
against a touch pad by means of which said spring element is
activatable.
51. An optical control device comprising a light source; at least
two optical waveguides, at least a first one of which being
configured as a transmitting waveguide being coupled to said light
source and cooperating with a second one of said optical
waveguides, said second optical waveguide being configured as a
receiving waveguide; a control element being movable between at
least two positions for controlling light input from said
transmitting waveguide into said receiving waveguide; and an
evaluation circuitry coupled to said receiving waveguide for
evaluating the light received by said receiving waveguide.
52. An optical control device, comprising a light source; an
optical waveguide coupled to said light source for receiving light
therefrom; a redirecting means for redirecting light emerging from
an end of said optical waveguide and for coupling said light back
into said end; a control element for controlling said light being
coupled back into said optical waveguide by said redirecting means;
and an evaluation circuitry coupled to said optical waveguide for
evaluating the light coupled back into said end by said redirecting
means.
53. The control device of claim 52, wherein said control element
comprises a redirecting means.
54. The control device of claim 52, wherein said redirecting means
comprises at least one reflecting,surface.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to a power tool comprising an optical
control which may, in particular, be configured as a switch, a
controller or a sensor.
[0002] In power tools a variety of switches and electrical controls
is used which may be commonly configured as non-locking keys, press
keys, slide switches, toggles or the like.
[0003] The configuration and location of such switches or
electrical controls cannot be chosen solely under ergonomic
considerations, but must, in particular, when the housing is made
from metal, follow the necessary protective regulations, whereby
design and assembly of the respective power tool is complicated to
a large extent.
[0004] From EP 0 126 253 A1 a screw driver has become known which
utilizes a light barrier fixed to the housing which allows to sense
a pot-like stop having axially extending trapezoid teeth, to
thereby sense, by means of the shifting of the stop, the diameter
of the tool used, to thereby control a speed regulator for the
motor of the screw driver, depending on the diameter sensed.
[0005] However, this light barrier, which may also be replaced by a
Hall-barrier, is coupled to an evaluation circuitry by means of an
electric wire. Thus, still an electric wire connection is
necessary.
SUMMARY OF THE INVENTION
[0006] In view of this it is a first object of the invention to
provide an improved power tool having a control device that may be
integrated into the housing thereof without the requirement of
electric wire connections.
[0007] It is a further object of the invention to provide a power
tool comprising an optical control device.
[0008] It is a further object of the invention to disclose a power
tool comprising an optical control that may, in particular, be
configured as a switching device, a regulation device or a sensor
device.
[0009] It is another object of the invention to disclose a power
tool comprising a control device allowing integration into the
housing of the power tool at any desired location, due to mainly
ergonomic considerations, without requiring particular insulation
steps when utilizing metal housing parts.
[0010] It is a further object of the invention to disclose a power
tool having an improved ergonomic design.
[0011] It is another object of the invention to provide a power
tool that can easily be operated by means of control devices in a
particular simple and reliable way.
[0012] It is another object of the invention to provide an optical
control device having a broad range of possible applications,
allowing an integration into power tools or into any other devices
such as house hold appliances or the like.
[0013] These and other objects of the invention are solved by a
power tool comprising a light optical control device, in particular
a switching device, regulation device or sensor device having at
least two optical waveguides, at least a first one of which being
configured as a transmitting waveguide is coupled to a light source
and cooperates with a second waveguide being configured as a
receiving waveguide that is coupled with an evaluation circuitry,
wherein the two waveguides are coupled to a control element that is
movable between at least two positions within which light signals
of different magnitudes are input from the transmitting waveguide
into the receiving waveguide.
[0014] Thus, the object of the invention is solved in a
surprisingly simple manner, namely, by utilizing two optical
waveguides and a control element which allows to control the input
of light signals into the receiving waveguide. Since the
waveguides, which may be designed as flexible guides, can be
integrated within the housing or even in a suitable manner on the
outer surface of the housing almost in any desired way, thereby
switching devices, control devices or sensor devices for a power
tool can be effected that can be tailored to the respective
individual needs, without requiring large space.
[0015] According to an alternative embodiment of the invention the
object of the invention is solved by a power tool comprising a
control device, in particular a switching device, regulation device
or sensor device having an optical waveguide into which light can
be input from a light source, wherein an evaluation circuitry is
coupled to the waveguide by means of which light irradiation
emerging from one end of the waveguide and redirected into the
waveguide via a redirecting means is evaluated, wherein the end is
coupled to a control element by means of which the irradiation
coupled back into the waveguide is controllable.
[0016] Also in this way the object of the invention is solved
completely. By contrast to the embodiment mentioned before, instead
of one transmitting waveguide and one receiving waveguide only a
single optical waveguide is utilized for transmitting and receiving
light signals, wherein the light emerging from the optical
waveguide at one end is input again and the intensity of this light
is evaluated.
[0017] Naturally, also the control element itself may be designed
as a redirecting means.
[0018] The power tool and the control device according to the
invention may be modified in various forms and may be subject to
various applications.
[0019] In case the evaluation circuitry does not only differentiate
between two states, and the intensity of the light signals coupled
into the receiving waveguide is evaluated, the control device can
also be designed as a continuous controller.
[0020] It should be noted that the term "optical waveguide" shall
not be understood to limit this to a waveguide utilized only for
visible light. By contrast, under the scope of this invention
"optical waveguide" shall include any waveguide that is suitable to
transport electromagnetic irradiation within the region of visible
light, infrared light, ultraviolet light or any other regions
adjacent thereto.
[0021] According to an advantageous development of the invention
the transmitting waveguide and the receiving waveguide at least in
the region of the control element are received in a unit protected
against the outside at least against dust.
[0022] In this way the control device can also be utilized under
rough operating conditions to which power tools are often
subjected.
[0023] According to an additional embodiment of the invention the
transmitting waveguide at a first end thereof is coupled with the
light source, while the receiving waveguide at a first end thereof
is coupled with the evaluation circuitry, wherein a second end of
the transmitting waveguide is arranged at a distance from a second
end of the receiving waveguide.
[0024] Now the input of the light signals emitted by the
transmitting waveguide into the second end of the receiving
waveguide can be influenced in various ways.
[0025] Thereby light optical switches with different defined
switching states can be realized, as well as non-locking keys,
sliding switches and rotary switches.
[0026] According to an improvement of the aforementioned embodiment
the control device is designed as an elastic form part surrounding
the second ends of the waveguides.
[0027] This has the advantage that the control element itself as
well as the second ends of the waveguides are protected against
influences from the environment in a robust and reliable way. The
control element may, e.g., be configured as a rubber part.
[0028] Herein the elastic form part is preferably configured as a
sleeve that is elastically deformable in the region between the
second ends for blocking the light signals input into the receiving
waveguide. To this end a thickening may be provided in the region
between the second ends.
[0029] In this way a control device of particularly simple and
robust design is realized.
[0030] According to an additional embodiment of the invention the
second ends of the waveguides are aligned with each other for
transmitting light signals into the receiving waveguide, wherein
the control element is configured for moving the second ends
relative to each other.
[0031] Also with such a design a particularly simple switch,
controller or sensor can be effected.
[0032] According to another embodiment of the invention the second
ends of the waveguides are aligned with each other for inputting
light signals into the receiving waveguides, wherein the control
element comprises a portion that is movable into the space between
the two ends.
[0033] According to an improvement of this embodiment the control
element is configured as a spring element, the portion of which
that is movable into the space between the second ends comprising a
light passing opening.
[0034] With such a design a non-locking key can be realized in a
particularly simple way, since the restoring force can be effected
readily by the spring element itself.
[0035] According to an advantageous development of the invention
the control element is covered by an elastic touch pad.
[0036] This has the advantage that by means of the elastic touch
pad a protection of the control element and of the waveguides
against environmental influences can be effected, whereby an
embodiment sealed against dust or even against liquid can be
reached. Since the touch pad is configured elastically, the control
element can be operated through the touch pad. If desired, also the
resilience of the touch pad can be utilized for effecting a
restoring force for the control element at the same time. Thereby,
the control device can be designed relatively thin, requiring only
small space.
[0037] According to a further development of the invention the
control element is designed as a slider which is slidable between
an idle position in which the second ends of the waveguides are not
aligned with each other, and between an operative position in which
the second ends are aligned with each other for transmitting light
signals into the receiving waveguide.
[0038] Thus a light optical slide switch or non-locking key switch
can be effected.
[0039] Herein the slider is lockable preferably in the operative
position and is biased toward the idle position.
[0040] According to another embodiment of the invention at least
one of the second ends is biased by a spring element or by its
self-tension into a direction substantially transversely to its
direction of extension, wherein the control element allows to move
the second end laterally between the idle position and the
operative position.
[0041] In this way a particularly simple design is effected.
[0042] According to an advantageous development of the invention
the slider is covered by an elastic touch pad to which it is firmly
connected and by which it is elastically biased into the idle
position or vice versa by the material tension of the touch pad, if
desired.
[0043] In this way an ergonomically particularly advantageous slide
switch can be effected, since by means of a locking in the
operative position an operation free of tiring is made possible at
small power requirement. By means of the bias into the direction of
the idle position the slide switch is restored again, when
released.
[0044] By linking the slider to an elastic touch pad lying
there-above, the bias into the direction of the idle position can
be effected in a particularly simple way, while at the same time an
encapsulation of the control device against environmental
influences is effected, since the touch pad may, for instance, be
made from rubber, a silicone material or the like.
[0045] According to a further embodiment of the invention the
transmitting waveguide comprises at least one light emitting
opening for radial emission which is coupled to a light receiving
opening of the receiving waveguide.
[0046] With such a design additional applications of the control
device are made possible. In particular, annular or partially
annular control elements are made possible.
[0047] According to an improvement of this design, the transmitting
waveguide and the receiving waveguide are at least partially
configured as annular waveguides that are held at a distance,
wherein the control element is configured as a switching ring by
means of which the transmitting waveguide and the receiving
waveguide are movable with respect to each other.
[0048] With such a design a switch that is actuable from all sides
can be realized.
[0049] Herein the transmitting and the receiving waveguides can be
held within an annular tube at a distance from each other, wherein
a transmission of light into the receiving waveguide is impeded in
an idle position, and wherein the switching ring is movable
relative to the tube and allows to deform the tube for inputting
light rays into the receiving waveguide.
[0050] In this way a switch having an annular control element can
be effected in a particularly simple way, while the resilience of
the tube can be utilized for effecting a restoring force.
[0051] According to an additional embodiment of the invention the
transmitting and the receiving waveguides are at least partially
configured as annular waveguides that are held at a distance from
each other, wherein the control element is configured as a
switching ring that allows to input light rays into the receiving
waveguide at least at one selected location when being in the
operative position.
[0052] With such a design a ring switch can be effected allowing
actuation at selected locations.
[0053] According to another embodiment of the invention the control
element is configured as a rotary slide being coupled with one of
the second ends of its waveguides for moving same between both
positions.
[0054] In this way a rotary switch can be effected in a
particularly simple way. Herein the control element may, for
instance, be configured as a switching ring that is rotatable
between an idle position and an operative position.
[0055] According to another embodiment of the invention the second
ends of the waveguides are arranged misaligned with respect to each
other, wherein the control element comprises means for inputting
the light signals emitted by the transmitting waveguide into the
receiving waveguide in at least one of the positions of the control
element.
[0056] With such a design additional application requirements with
respect to the control device can be reached, in particular,
annular or partially annular control elements can be effected that
are rotatable between several switching positions.
[0057] The means for inputting the light may, for instance,
comprise a prism, a reflecting surface or any other redirecting
element that is movable into a position for transmitting light
signals from the transmitting waveguide to the receiving
waveguide.
[0058] In addition, the second ends, when being in the idle
position, may be coupled to an additional redirecting means, which
may also be configured as a prism, for redirecting light signals
emitted by the transmitting waveguide onto an optical display.
[0059] In this way the light signals emitted by the transmitting
waveguide can be utilized for optically signaling the idle position
of the switch.
[0060] According to an advantageous development of the
aforementioned embodiments the control element may comprise a
rotary switch upon which the means for inputting and/or the
redirecting element are received.
[0061] Herein the rotary switch may be designed as a switching ring
which is biased into the direction of an idle position.
[0062] In addition, the switching ring may be elastically biased
into a middle position in which light signals from the transmitting
waveguide are redirected by the redirecting element toward a
display surface for optically signaling the idle position.
[0063] In addition, the switching ring may be movable also from the
idle position in a first direction of rotation into a first
operative position in which light signals are input into the
receiving waveguide, and in a second direction of rotation, into a
second operative position in which also light signals are input
into the receiving waveguide.
[0064] In this way an annular switch can be effected having a
middle idle position which is optically signaled, as well as two
operative positions which may be reached by rotating into one or
into another direction of rotation.
[0065] According to an additional embodiment of the invention the
rotary slide comprises an elastic touch pad that is received
circumferentially in a housing opening, wherein the means for
inputting the light rays into the receiving waveguide and/or the
redirecting means are received on the elastic touch pad.
[0066] In this way a rotary switch can be effected particularly
simple.
[0067] Herein the resilience of the touch pad may be utilized for
elastically biasing the control element into the direction of an
idle position or vice versa.
[0068] Again, the touch pad may be utilized simultaneously to
protect or to completely seal the waveguides and the control
element against environmental influences.
[0069] According to another embodiment of the invention the means
for inputting may comprise a mirror element that is movable into a
position for transmitting light rays from the transmitting
waveguide into the receiving waveguide.
[0070] Thereby additional requirements with respect to the control
device may be met. In particular, by means of particularly sensing
the light signals received by the receiving waveguide a regulating
device can be effected.
[0071] According to a preferred development of this embodiment the
mirror element may comprise a spring element that is clamped at one
end thereof and that holds a mirror element at another end thereof
and that may be moved against the action of the spring force.
[0072] In this way by means of the spring element simultaneously a
restoring force can be effected for biasing the control element,
e.g. into an idle position.
[0073] Herein the mirror surface may be continuously pivotable
between a position in which no light signals are input into the
receiving waveguide, and between a position in which light emerging
from the transmitting waveguide is input almost completely into the
receiving waveguide.
[0074] In this way a continuous sensing of the light signals
received by the receiving waveguide and, thus, a continuous
controller can be effected.
[0075] Herein the spring element may rest against a touch pad by
means of which the spring element is activatable.
[0076] In this way a non-locking key can be realized that can be
used either for switching on/off and/or for continuous control, in
particular with regard to a power tool having a housing in pistol
form, e.g. for activating the motor and for controlling the speed
thereof.
[0077] According to a further development of the invention a power
tool comprises at least one activation part or attachment part that
is coupled to a control device of the kind explained above.
[0078] In this way various switching regulating or control
functions may be reached in a particularly advantageous way.
[0079] For instance, power tools having a supplemental handle, such
as a stock handle, may be monitored by means of the control device
for ensuring that the operator has gripped the stock handle, thus
ensuring a two-handed operation (i.e. activation of the drive only
upon simultaneous gripping of another gripping part and activation
of an additional switch). In this way, for instance, an optically
controlled two-handed angle grinder can be designed. In addition,
such a control device can be utilized for instance, to monitor
whether a particular attachment part is located on the power tool
or not. Thus, for instance, a starting of an angle grinder can be
avoided in case the required protection hood is not provided.
[0080] In addition, it may be monitored, whether an activation
part, for instance, a clamping lever is located in a particular
required position. Finally also particular attachment parts or
accessory parts which are suitable only for utilization with a
particular power tool, can be coded by means of the control device.
Thus it may be ensured, for instance, that a particular protection
hood is mounted on a particular angle grinder, while in all other
cases a starting of the angle grinder is avoided by means of the
control device.
[0081] A power tool having a clamping lever for clamping a tool
that is movable between a clamping position and a loose position,
may be controlled, as to whether the clamping lever is in the
clamping position, by means of a control device assigned to the
clamping lever. The control device may be configured such that both
ends of the waveguides may be enclosed by an elastic sleeve having
a thickening in the region between both ends and being elastically
deformable for blocking light signals transmitted into the
receiving waveguide.
[0082] Such a control device can be integrated in a simple way into
the gear head of a power tool in such a way that the clamping lever
activates the control device when being in the clamping
position.
[0083] Herein the control device may, in particular, be configured
as a switch allowing an activation of the motor only when the
clamping lever is in the clamping position.
[0084] According to an additional embodiment of the invention at
least one of the waveguides is integrated into a housing wall.
Herein the waveguide may be located directly within the housing
wall or on the outer side or the inner side thereof.
[0085] In each case thereby the total size of the power tool may be
reduced effectively.
[0086] According to an additional embodiment of the invention the
housing of a power tool may be bonded to a touch pad of the control
device by means of two-component-technology.
[0087] By means of this "two-component-molding-technology" an
intimate bonding between a softer elastic material and another
plastic material can be effected. Thus, for instance, a rubber
touch pad or a silicone touch pad may be effectively bonded to the
remaining (hard) housing part (to this end, firstly one of the two
materials is injected into a mold, thereafter the other material is
injected into the mold, while the first material is still in a
partially soft state, thereby effecting a good bonding between the
materials). In this way an additional sealing of the touch pad or
of the control device, respectively, against environmental
influences from the outside or against contamination from the
inside can be effected.
[0088] In addition, the elasticity of the touch pad may be utilized
for effecting a restoring force for the switch or for the
non-locking key, respectively.
[0089] Needless to say, the features of the invention mentioned
before may not only be utilized in the combination given, but also
in any other combination or on its own without leaving the scope of
the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0090] Additional features and advantages of the invention result
from the following description of preferred embodiments with
reference to the drawing. In the drawings:
[0091] FIG. 1 shows a first embodiment of a control device
according to the invention in a simplified representation denoting
the principle;
[0092] FIG. 1a shows a power tool having a control device according
to FIG. 1, wherein only the gear head of the power tool is shown in
perspective view;
[0093] FIG. 1b shows a complete view of the power tool according to
FIG. 1a;
[0094] FIG. 1c shows a detailed view of a switch according to FIG.
1b;
[0095] FIG. 2 shows a control device modified with respect to FIG.
1, wherein only the two ends of two waveguides and a control
element having the form of a spring element assigned thereto are
depicted;
[0096] FIG. 2a shows a power tool having two control devices
according to FIG. 2, shown in perspective, simplified
representation;
[0097] FIGS. 3a)-d) show an additional embodiment of a control
device configured as a slide switch, shown in strongly enlarged,
partially sectioned view;
[0098] FIG. 4 shows an additional embodiment of the control device
according to the invention comprising a switching ring, shown in
cross-section;
[0099] FIG. 4a shows an enlarged cut-out of the switching ring
together with a profile tube assigned thereto according to FIG.
4;
[0100] FIG. 4b shows a perspective view of a power tool comprising
three control devices according to the invention;
[0101] FIG. 5 shows a representation of another control device
according to the invention comprising annular waveguides which
allow to block light input into the receiving waveguide at four
locations by means of an annular control element;
[0102] FIG. 5a shows a cross-section of the control device
according to FIG. 5;
[0103] FIG. 6 shows another embodiment of the control device
according to the invention having an annular control element, shown
in cross-section in an idle position;
[0104] FIG. 6a shows the control device according to FIG. 6 in an
operative position;
[0105] FIG. 7 shows another embodiment of the control device
according to the invention in perspective view;
[0106] FIG. 7a shows a perspective view of the control element
according to FIG. 7;
[0107] FIG. 7b shows a perspective view of a metal ring for making
the switching ring according to FIG. 7a, with mounted spring
elements, depicted schematically;
[0108] FIG. 7c shows an enlarged detailed section through the rim
of the switching ring according to FIG. 7, in the region of a
sealing to the housing;
[0109] FIG. 8 shows a further embodiment of a control device
according to the invention configured for mounting into a
respective opening of a housing, shown in perspective view seen
from the inside;
[0110] FIG. 8a shows the control device according to FIG. 8 in an
activated position;
[0111] FIG. 8b shows a power tool comprising two control devices
according to FIG. 8;
[0112] FIG. 9 shows a further embodiment of a control device
according to the invention in considerably enlarged, partially
sectioned representation;
[0113] FIG. 9a shows a top view of the control device according to
FIG. 9, after removal of the elastic touch pad arranged
there-above;
[0114] FIG. 9b shows a perspective view of a power tool in pistol
form comprising a control device according to FIG. 9;
[0115] FIG. 10 shows a modification of the control device according
to FIG. 9 in schematic, enlarged representation, in which, in
particular, the both ends of the waveguides and a reflection
element assigned thereto can be seen;
[0116] FIG. 10a shows a section through the control device
according to FIG. 10 in the region of the movable reflection
surface;
[0117] FIG. 10b shows an enlarged representation of the touch pad
according to FIG. 10a;
[0118] FIG. 11 shows a schematic representation of an alternative
embodiment of the invention and
[0119] FIG. 12 shows a modification of the embodiment according to
FIG. 11 in schematic representation.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
[0120] In FIG. 1 a first embodiment of a control device according
to the invention is designated in total with reference numeral
100.
[0121] The control device 100 comprises a first optical waveguide
102 which is configured as a transmitting waveguide, and further a
second optical waveguide 108, which is configured as receiving
waveguide. The receiving waveguide 102 comprises a first end 104
into which light from a light source 120, which may for instance be
configured as LED, may be input.
[0122] A second end 106 of the receiving waveguide 102 is arranged
at a small distance to an assigned second end 112 of the receiving
waveguide 108. The first end 110 of the receiving waveguide 108 is
connected to an evaluation circuitry 114 within which the light
signals received from the receiving waveguide 108 are
electronically evaluated to output independent therefrom output
signals A.sub.1, A.sub.2 at output ports 116, 118.
[0123] The second ends 106, 112 of the optical waveguides 102, 108
are enclosed by a control element 122 which, in the embodiment
shown, is configured as a rubber sleeve that firmly encloses the
second ends 106, 112 and comprises a build-up 123 surrounding the
middle. In the region between the second ends 106, 112 in FIG. 1 a
light ray 124 is shown that enters from the transmitting waveguide
102 into the receiving waveguide 108. In addition, in the region
between the second ends 106, 112, the rubber sleeve has a build-up
or inner bead 125 that protrudes into the direction of the light
ray 124. Since the control element 122 or the sleeve is rubber
elastic, the build-up 123 can be gripped from the outside and be
pressed together, so that the light ray 124 is interrupted. This is
recorded by the evaluation circuitry 114 that outputs a respective
output voltage at its output ports 116, 118. If the control device
100 shall be configured as a switch, then the evaluation circuitry
114 may comprise a relay or a semiconductor switch that opens (or
closes) the output ports 116, 118, if the light signals received
from receiving waveguide 108 fall below a certain threshold
intensity.
[0124] Basically it is also possible to utilize the evaluation
circuitry 114 for continuously evaluating the intensity of the
light signals received for outputting independent thereof a
continuous output signal or a digital output signal which may be a
control signal.
[0125] FIG. 1a shows the application of the control device 100
according to FIG. 1 as a sensor by means of which the position of a
clamping lever 134 of a power tool 130 is monitored.
[0126] The power tool 130 is shown in FIG. 1a only in the region of
its gear head 132. The power tool 130 comprises the clamping lever
134 for clamping a tool. The clamping lever 134 can be pivoted
between the open position shown in FIG. 1a and between a closed
position in which the clamping lever 134 rests against the surface
of the gear head 132. In this supporting region of the clamping
lever 134 a control device 100 according to FIG. 1 is located. The
two light waveguides 102, 108 are fixed on the top side of the gear
head 132 by means of a plastic part 136 by clipping in a suitable
position, so that the control element 122 is located in the
supporting region of clamping lever 134.
[0127] Preferably the optical waveguides 102, 108 are configured as
flexible optical waveguides and may be permanently deformed by
local heating, so that desired bendings can be achieved. For
instance, with waveguides of 2.2 mm thickness a 90 degree bending
having a bending radius of 1 mm can be achieved. Herein light
transmission is hardly not impaired. A distance between the second
ends as small as possible is important for a good light
transmission.
[0128] When the clamping lever 134 is closed, the control element
122 is pressed together, so that the light ray 124 is interrupted
which is recorded by the evaluation circuitry 114.
[0129] In FIG. 1b a power tool 130 is shown in total.
[0130] Apart from the control device for controlling the position
of the clamping lever 134 the power tool comprises three additional
control devices of the embodiment according to FIG. 1 which are
received on a rod-like housing 138.
[0131] In the case shown the power tool 130 is configured as an
angle grinder which is configured for one-handed operation.
[0132] In the middle of housing 138 an oblong touch pad 148 is
located by means which a control device configured as a switch 150
located there-below is actuable. The switch 150 can be activated by
the ball of the thumb. It serves as a main switch for activating
the motor of the power tool (dead man's switch). When the machine
is gripped with the hand in the region of the touch pad 148, the
machine is ready to start. Herein also the clamping lever 134 must
be in its closed position so that the light ray is interrupted
which is recorded by the optical non-locking key.
[0133] Switching on/off the machine is now possible by two finger
non-locking keys 142, 146 located in the front region of both side
faces of housing 138. They each operate an optical non-locking key,
wherein for operating the power tool 130 only one of the two
non-locking keys 142, 146 must be pressed. These non-locking keys
142, 146 are covered by a touch pad 140 or 144, respectively, which
is made from rubber. The non-locking keys 142, 146 and the
associated touch pads 140, 144 are made very soft, so that they can
be permanently pressed during operation of the machine.
[0134] In this way a particularly ergonomic design of the power
tool 130 is reached, that is not only suitable for right-handed
operation, but also for left-handed operation, wherein also a
position control for clamping lever 134 is ensured.
[0135] The optical waveguides may be located below the touch pads
on the outer surface of housing 138, such as shown with respect to
touch pad 140 (see FIG. 1c). When the housing 138 is composed of
two shells, then the assembly is simplified by inserting all
components into one shell. The rubber switch pads for the finger
non-locking keys can be integrated into the housing as shown. At
the same time thereby a noise attenuation is reached by rubberized
inner walls, while locally rubberized outer surfaces allow for a
better gripping comfort and ensure a vibration absorbing.
[0136] Herein by means of the light optical control device 100
located in the region of the gear head 132 which is made from
metal, a position control for the clamping lever 134 is obtained in
a particularly simple way without requiring costly insulation
measures for obtaining contact safety in the region of the metallic
gear head.
[0137] A modification of the control device 100 is shown
schematically in FIG. 2 and denoted in total with numeral 200. For
ease of illustration the transmitting waveguide 202 and the
receiving waveguide 208 are merely shown in the region of their
second ends 206, 212. The control element 222 assigned thereto is
configured as a formed spring having two lateral wings and a middle
section 215 depending downwardly from the wings, that protrudes
into the region between both ends 206, 212 and thus blocks a light
ray, when in idle position. In the upper region of section 215 of
control element 222 a light passing opening is provided in a
suitable position which is moved between the two ends 206, 212 for
passing light, when the control element 222 is pressed down into
the direction of arrow 216.
[0138] In FIG. 2 as well as in subsequent Figures the remaining
parts of the control device, such as the light source and the
evaluation circuitry are not shown, for sake of simplicity.
[0139] The embodiment according to FIG. 2 can advantageously be
applied as a non-locking key wherein a restoring can be reached by
means of the spring force of the control element 222 or by means of
the spring element.
[0140] Basically also in the idle position a light ray could be
passed while it could be interrupted when the spring is pressed
down.
[0141] In FIG. 2a a power tool taking the form of an angle grinder
that utilizes such a control device 200 is depicted and denoted in
total with numeral 230.
[0142] On housing 238 of the power tool 230 two non-locking keys
244, 248 are provided on opposite sides, both being covered by
touch pads 242, 246. On the tool-facing end of the power tool 230 a
gear head 232 made from metal is provided upon which a clamping
lever 234 is attached pivotably, while again a non-locking key (not
shown) is provided for monitoring the closed position of the
clamping lever 234. All the optical waveguides are located on the
outer side of the motor housing below a rubber surface 240. Thereby
the waveguides are not collated in the air stream, so that there is
no danger due to elevated temperatures. In the housing 238 a
respective recess may be located for the optical waveguides, so
that the rubber surface 240 that also includes the touch pads 242,
246 can be made flush with housing 238. The optical waveguides can
also be located on the housing wall or on the inner side of the
housing wall, whereby more space is made available for the cooling
air stream.
[0143] In addition a third non-locking key may be located at the
end of housing 238 opposite the rubber surface 240 intended for
starting the device in two-handed operation. For switching on the
power tool 230 selectively only one of the two non-locking keys
244, 248 or the third non-locking key (not shown) must be pressed.
The non-locking keys pass a light signal when pressed. Thereby an
activation of the power tool 230 is depressed in case of default,
if the signal path is interrupted.
[0144] In addition the non-locking key for monitoring the clamping
lever 234 must be activated to allow a starting of the power tool
230.
[0145] In FIGS. 3a)-3d) another modification of the control device
according to the invention is depicted in total with numeral
300.
[0146] Herein the control device is configured as a so-called slide
switch which is slidable from an idle position, shown in FIGS. 3a)
and b), into an operative position, shown in FIGS. 3c) and d).
FIGS. 3a) and 3c) are shown including touch pads, while in FIGS.
3b) and 3d) the touch pads are not shown.
[0147] To this end a transmitting waveguide 302 is received with
second end 306 firmly in housing 318. The transmitting waveguide
302 cooperates with a receiving waveguide 308 that is aligned with
the transmitting waveguide 306 while the second end 312 of the
receiving waveguide 308 can be laterally displaced by means of the
control element 322, configured as a slider, for interrupting the
transmission of light signals into the receiving waveguide 308. The
receiving waveguide 308, which is configured flexible, may be
elastically biased to the top in the direction towards a slider 322
merely by means of its self-tension or by means of a spring
element.
[0148] The slider 322 comprises an oblong form which is almost
wedge-shaped and comprises at its end facing the transmitting
waveguide 302 a locking surface 316 protruding downwardly which may
be received for locking in a correspondingly formed recess 320 of
housing 318. The slider 322 is firmly connected with a touch pad
314 located there-above and made from a rubber pad, which may, for
instance, be obtained by application of
two-component-molding-technology. When switching, that is when
moving from the idle position shown in FIGS. 3a) and b) into the
operative position, shown in FIGS. 3c) and d), thus by means of the
touch pad 314 a bias is generated that restores the slider 322
again into its idle position upon release. During operation the
operator must only overcome the restoring force by a soft pressing,
while the main force is provided by the locking, when the locking
surface 316 is locked into the recess 320.
[0149] For activation the slider 322 must only be shifted from its
idle position according to FIGS. 3a) and b) by roughly two
millimeters, until the locking surface 316 locks into the recess
320, and simultaneously, the second end 312 of the receiving
waveguide 308 is aligned with the second end 306 of the
transmitting waveguide 302.
[0150] In view of an embodiment as a push-button switch the
embodiment according to FIG. 3 has the advantage that the holding
force for holding the switch during operation can be designed
independently from the force for activating the switch. Thus it is
made possible to select the force for switching on relatively high
to protect against inadvertent switching on, while keeping the
holding force low, to thereby reach a higher operating comfort.
Also a power tool that is equipped with such a slide switch cannot
start when the housing is gripped, for instance, during
transportation, by contrast, an intentional switching on is
necessary.
[0151] Two further embodiments of the control device according to
the invention which are configured as a ring switch are described
in the following with reference to FIGS. 4 and 5.
[0152] The embodiment of the control device according to FIGS. 4
and 4a depicted in total with numeral 400 is an axial slide switch
which is activatable by axially displacing the control elements
422, that is configured as a switching ring.
[0153] An annular transmitting waveguide 402 and an annular
receiving waveguide 408 are received at a distance in an annular
profile tube 410 which may, for instance, be made from rubber or
another elastic material. Both optical waveguides 402, 408 are
configured for a radial emission or a radial input,
respectively.
[0154] In the idle position shown in FIG. 4a a light input from
transmitting waveguide 402 into the receiving waveguide 408 is
blocked by a protrusion 412 of profile tube 410 lying
there-between. When the control element 422 or the switching ring,
respectively, is axially displaced into the direction of the
profile tube, then the profile tube is pressed together by an
annular shoulder 424 of control element 422, thereby the protrusion
412 is pressed to the side, and both optical waveguides 402, 408
get into contact, so that light from the transmitting waveguide 402
is transmitted into the receiving waveguide 408.
[0155] Herein in addition a locking can be provided for the control
element 422 for holding the control element 422 with a small
holding force in the operative position. Upon release a restoring
of the control element 422 into the idle position is reached due to
the bias that is reached by the bulging of the profile tube
410.
[0156] In FIG. 4b a power tool that is configured as a two-handed
angle grinder, is depicted in total with numeral 430.
[0157] The power tool 430 comprises an axial slide switch 442 that
is designed according to FIGS. 4 or 4a, respectively.
[0158] The power tool 430 is gripped with one hand at a rear
gripping part 444 at the end of housing 438 and is held with the
other hand by means of a stock handle 446 which may be attached on
the left side of the gear head in the position shown in FIG.
4b.
[0159] At the stock handle 446 an additional control device 440 is
provided which may, for instance, be designed according to FIG. 1
or 2. The control devices 440, 442 are designed for a two-handed
operation, so that the power tool can be activated only when
simultaneously gripping gripping part 444 and stock handle 446.
[0160] The two-handed angle grinder 430 is shown here in FIG. 4b
also with a hood 448. The hood 448 cooperates with a control device
441 that can monitor whether the hood is attached or not, so that a
start-up of the power tool 430 is only possible when the hood is
attached. Herein also a coding of the hood may be provided to
ensure that only a particular type of hood can be utilized for a
particular power tool, while an activation of the power tool is not
possible when a hood not suitable is attached.
[0161] The power tool 430 is configured for a two-handed operation,
as mentioned before. Only when the ring switch 442 is activated,
while simultaneously the switch 440 on stock handle 446 is
activated with the other hand, a starting is possible. By means of
the ring switch a switch activation is made possible in different
gripping positions, so that also with different applications, such
as roughing-down or separating, an activation of the switch is made
possible in each gripping position.
[0162] A further embodiment of a control device according to the
invention having annular optical waveguides is shown in FIGS. 5 and
5a and depicted in total with the numeral 500.
[0163] Herein an annular transmitting waveguide 502 comprises in
total four defined light emerging positions 503, 504, 505, 506 that
are angularly displaced to each other by 90 degrees each, and that
cooperate with respective light input regions 509, 510, 511, 512 of
an annular receiving waveguide 508 located on the inner side.
[0164] The light waveguides 502, 508 are supported by an annular
housing 528, as can be seen from FIG. 5a. The control element 522
is configured as a ring having four switching surfaces 524
protruding laterally therefrom by means of which a rib 526
protruding from the control element 522 or the switching ring can
be shifted into the respective interspace between the light
emerging regions 503, 504, 505, 506 or the light input regions 509,
510, 511, 512, respectively, for blocking the light
transmission.
[0165] In the upper part of FIG. 5a an activated position or
operative position of the switch is shown, since the upper
switching surface 524 is located outside the transmission region
between transmitting waveguide 502 and receiving waveguide 508.
[0166] Further embodiments of the control device according to the
invention which are configured as rotary switches are described in
the following with reference to FIGS. 6 to 8.
[0167] In FIGS. 6 and 6a a control device according to the
invention is depicted in total with numeral 600. On an annular
housing 624 a control element 622 is received that is configured as
a switching ring which is actuable by means of rotation. In the
wall of housing 624 a transmitting waveguide 602 and a receiving
waveguide 608 are supported. Herein the second end 606 of
transmitting waveguide 602 is movable by means of control element
622 between a non activated position according to FIG. 6 in which
the second end 606 is not aligned with the second end 612 of the
receiving waveguide 608, and between an activated position or
operative position, in which both ends 606, 612 are aligned with
each other. The switching operation is effected by rotating the
control element 622, whereby the second end 606 of the transmitting
waveguide 602 is moved between the two positions shown in FIGS. 6
and 6a.
[0168] A further embodiment of a control device according to the
invention is denoted in total in FIGS. 7 and 7a with numeral
700.
[0169] An annular control element 722 is supported on an annular
housing 714, the control element being rotatable between a middle
idle position and two operative positions by means of rotating into
one direction of rotation or into the other direction of
rotation.
[0170] In addition, the idle position is optically displayed by
redirecting the light from the transmitting waveguide 702 onto an
optical display 716, so that for instance a red dot shines when the
power plug of the machine is connected. The switch is closed, when
the control element 722 is rotated clockwise or anti clockwise, as
will be explained in the following.
[0171] According to FIG. 7a a transmitting waveguide 702 and a
receiving waveguide 708 are attached to housing 714 in a way not
shown, so that their second ends 706, 712 are held adjacent each
other, so that no light transmission there between is possible.
[0172] To effect a light transmission between the second ends 706,
712, a redirecting element is necessary that must be moved into a
suitable position in front of the second ends 706, 712, so that the
light emerging from the transmitting waveguide 702 is redirected
into the receiving waveguide 708.
[0173] To this end on the inner side of control element 722 an
insert 718 is received on which a first prism 724, followed by a
redirecting element 720 and second prism 726 are supported adjacent
each other.
[0174] While the middle redirecting element 720 allows to redirect
a light ray emerging from the transmitting waveguide 702 to the
outside onto the optical display 716, the two prisms 724, 726 are
configured and arranged as such, that always when a prism 724 or
726 is located in front of the second ends 706, 712, the light
emerging from transmitting waveguide 702 is redirected into the
receiving waveguide 708.
[0175] Thus in the middle idle position shown in FIG. 7a the light
emerging from transmitting waveguide 702 is redirected to the
outside onto optical display 716 to thereby signal the activation
of the control device or of a machine, e.g. an angle grinder,
respectively, controlled thereby. When the control element 722 is
rotated from its idle position either clockwise or anti clockwise,
until one of the two prisms 724, 726 arrives in front of the second
ends 706, 712 and redirects the light into the receiving waveguide
708. Then an activated position or operative position is reached in
which the control element 722 must be held or can possibly be
locked. When the control element 722 is released, it moves from
each of the operative positions back into the middle position being
idle position according to FIG. 7a.
[0176] To this end, the control element 722 is biased into the idle
position by means of two spring elements 730, 732, which are shown
in FIGS. 7b exemplarily.
[0177] The control element 722 comprises an open switching ring 723
according to FIG. 7b, which may for instance be closed by a
positive-fit metal clamp during assembly. The ring may be composed
of a tape-formed supporting material, for instance from metal, that
prevents an elongation of the ring and is molded from the outside
with an elastic cover having several gripping recesses and two
lateral rims 736, which are configured as sealing lips 738 for
protecting the switching ring against contamination (FIG. 7c).
[0178] In FIG. 7b the still open switching ring 723 before molding
is shown with respective spring elements 730, 732 located at its
two ends 728, 734 facing each other.
[0179] The insert 718 on which the two lateral prisms 724, 726 and
the middle redirecting element or redirecting prism 720 are
received, may for instance be formed as a transparent molded part
from PMMA.
[0180] Another modification of the control device according to the
invention is shown in FIGS. 8 and 8a and depicted in total with
numeral 800. To this end on a housing not shown again a
transmitting waveguide 802 and a receiving waveguide 808 are
arranged with their second ends 806, 812 beside each other, so that
a light transmission is only possible, if a light ray emerging from
transmitting waveguide 802 is redirected by means of a redirecting
element into the receiving waveguide 808.
[0181] The control element 822 comprises a cap 829 made from an
elastic material, such as rubber, that is firmly connected at a
circumferential rim 825 with a housing opening not shown. Within
the cap a slider 826 is received upon which two prisms 827, 828 are
received adjacent each other.
[0182] According to FIG. 8 the control device 800 is in an idle
position, in which light emerging from the transmitting waveguide
802 is deflected laterally by the prism 827 and cannot enter into
the receiving waveguide 808.
[0183] From this idle position the control element 822 can either
be displaced into one rotary direction, so that the position
according to FIG. 8a is reached, in which light emerging from the
transmitting waveguide 802 is redirected via the prism 827 into the
receiving waveguide 808, or may be displaced into the opposite
rotary direction into a second operative position (not shown).
[0184] In the second operative position the prism 828 is located in
front of the second ends 806, 812 to redirect light from the
transmitting waveguide 802 into the receiving waveguide 808.
[0185] Thus a switching device can be obtained in a simple way
having a middle idle position and two lateral operative positions
that can be reached from the idle position by rotating into one
direction of rotation or by rotating into the opposite direction of
rotation.
[0186] Herein the elasticity of the cap 829 made, for instance,
from rubber can be utilized for providing a restoring force for
biasing the control element 822 into the middle position, for
instance.
[0187] In FIG. 8b a power tool that is equipped with two of these
control devices is depicted in total with numeral 830. Again it is
configured as an angle grinder shown largely simplified that can be
operated either one-handed or two-handed.
[0188] To this end at the front end of housing 832 at the
transition to the gear head 834 a first rotary switch 836 according
to FIG. 8 is provided, and at the rear end of housing 832 on a slim
gripping part 840 a second rotary switch 838 is provided. The rear
rotary switch 838 is configured for a two-handed operation, when
the machine is gripped at its rear gripping part 840 and the rotary
switch 838 is activated, while the machine is held simultaneously
by means of a stock handle (not shown) with the second hand. The
stock handle may be screwed into the gear head 834 on the left or
right side. By contrast, the rotary switch 836 may be utilized for
single-handed operation. To this end another rotary switch may be
located on the opposite side which cannot be seen in FIG. 8b, so
that the machine can be easily gripped from the left or from the
right and can be activated simultaneously.
[0189] Another modification of the control device according to the
invention is depicted in FIGS. 9 and 9a and denoted in total with
numeral 900.
[0190] Herein a transmitting waveguide 902 and a receiving
waveguide 908 are received on a housing 926, so that light emerging
from the second end 906 of transmitting waveguide 902 can only be
input into the second end 912 of the receiving waveguide by means
of a respective redirecting element.
[0191] By contrast to the redirecting prisms utilized with the
aforementioned embodiments, in the embodiment according to FIG. 9 a
spring element 923 is provided that is clamped with one end 924
firmly in housing 926 and that is movable at its second end 925
against the action of its spring tension.
[0192] In housing 926 a recess 927 is provided so that the spring
element 923 is movable with its second end 925 into a position in
front of the second ends 906, 912 of the optical waveguides 902,
908. Since the second end 925 is metallized, for instance the
spring element 923 may be formed from polished stainless steel,
light emerging from the transmitting waveguide 902 is redirected
into the receiving waveguide 908, when the second end 925 of the
spring element 923 is located in front of the second ends 906,
912.
[0193] As can further be seen from FIG. 9, the spring element 923
of control element 922 is covered by a touch pad 928, that may
preferably be made from an elastic material, such as rubber, and by
which the spring element 923 is held in its idle position (no input
of light signals into the receiving waveguide 908). When the touch
pad 928 in the region of the spring element 923 is pressed down,
then the spring element 923 is moved into its operative position,
so that light from the transmitting waveguide 902 is redirected
into the receiving waveguide 908. Upon release the spring element
923 moves to the outside under the action of its spring force while
bulging the touch pad 928 to the outside.
[0194] Such a control device 900 can advantageously be applied as a
non-locking key that may be utilized for instance in a power tool
930 according to FIG. 9b. The power tool 930 is a drilling machine
or a screw drive in pistol form which comprises a pistol hand grip
932 for activating a control device 900. If desired, the intensity
of the light signals input into the receiving waveguide 908 may be
evaluated continuously, so that the control device 900 can be
utilized not only as a switch, but also as a controller, for
instance to control the speed of the power tool 930.
[0195] In FIGS. 10, 10a, 10b a further embodiment of the control
device according to the invention is depicted schematically and
denoted in total with numeral 1000.
[0196] The control device 1000 largely corresponds to control
device 900 according to FIG. 9, since again a transmitting
waveguide 1002 and a receiving waveguide 1008 are arranged at an
angle to each other, so that normally no transmission of light
signals from the transmitting waveguide 1002 into the receiving
waveguide 1008 is possible. To this end a redirecting element is
necessary that is shown in FIGS. 10 and 10a schematically with
numeral 1042. This redirecting element 1042 may have a metallized
surface, however, in the present case already the embodiment of the
surface as a white plastic part is sufficient, since the reflection
is sufficient to input a light signal from the transmitting
waveguide 1002 into the receiving waveguide 1008. The control
element 1022 for moving this redirecting element 1042 may, as shown
in FIG. 10a, comprise a touch pad 1040 which is connected to a
housing 1038 by means of two-component molding technology and which
acts onto the redirecting element 1042 located there below, for
moving same against the action of a spring element 1044 into a
position, in which the light signals from the second end 1006 of
the transmitting waveguide 1002 are input into the second end 1012
of the receiving waveguide 1008.
[0197] The design of the touch pad in two-component-technology can
better be seen from the enlarged representation according to FIG.
10b. The two-component-technology leads to a completely sealed
touch pad 1040, so that the control element 1000 can be protected
against environmental influences from outside (or also against
contamination from inside).
[0198] A further embodiment of a control device according to the
invention is schematically shown in FIG. 11 and denoted in total
with numeral 1100. Into a transmitting/receiving waveguide 1102
light signals from a light source (not shown) are input, that
emerge from one end 1128 of the transmitting/receiving waveguide
1102 and that are input again into the transmitting/receiving
waveguide 1102 at a corresponding reflecting surface 1126. An
evaluation of the light signals returned can be effected directly
at the transmitting/receiving waveguide 1102 or in a separate
receiving waveguide 1108 which is coupled with the
transmitting/receiving waveguide 1102 by means of a beam splitter
1124 for decoupling a part of the light signals. In the region 1128
of the transmitting/receiving waveguide thus a single optical
waveguide is sufficient to transmit the necessary light signals and
to return them to the evaluating device. Such an embodiment may
have advantages in particular under restrained spatial conditions.
The control element 1122 my, for instance, be a non-locking key
that is movable into the space between 1128 and the reflecting
surface 1126.
[0199] If, due to design considerations, a reflecting surface 1126
should not be possible at the location shown in the drawing, then
the control element 1122 may also serve as reflecting surface.
[0200] A modification of the embodiment according to FIG. 11 is
shown in FIG. 12 and designated in total with numeral 1200.
[0201] Herein a frequency modulated light signal is input into a
transmitting/receiving waveguide 1202 that emerges via an end 1228
of the transmitting/receiving waveguide 1202 and is reflected at a
respective reflecting surface 1226. By varying the distance between
the end 1228 and the reflecting surface 1226 a phase shift of the
light signal returned to the end 1228 results. The evaluation is
preferably done by means of a receiving waveguide 1208 which is
coupled by means of a beam splitter 1224 and the output signal of
which is input to an evaluation circuitry not shown. Herein the
reflecting surface 1226 may be part of the control element 1222
which merely must be moved relative to the end 1228. The evaluation
circuitry evaluates the path difference .DELTA.z. Thus the
arrangement described can serve as a continuous controller.
* * * * *