U.S. patent application number 10/587688 was filed with the patent office on 2008-11-06 for portable drive unit.
Invention is credited to Frank Fuchs, Juergen Hesse, Steffen Tiede.
Application Number | 20080271280 10/587688 |
Document ID | / |
Family ID | 35788353 |
Filed Date | 2008-11-06 |
United States Patent
Application |
20080271280 |
Kind Code |
A1 |
Tiede; Steffen ; et
al. |
November 6, 2008 |
Portable Drive Unit
Abstract
A portable drive unit (10) for operating a handheld power tool
(70) by means of suction and/or blown air, is portable in an
especially handy and space-saving way in that it has a housing
(11), which is designed as a case (13) that is closable with a lid
(24), and that its air feeding power is adapted to the power
requirement of the handheld power tool (70), and it serves to store
at least one such or similar handheld power tool (70), particularly
with its accessories, such as air-carrying tubes and hoses.
Inventors: |
Tiede; Steffen; (Herrenberg,
DE) ; Hesse; Juergen; (Waldenbuch, DE) ;
Fuchs; Frank; (Rutesheim, DE) |
Correspondence
Address: |
STRIKER, STRIKER & STENBY
103 East Neck Road
Huntington
NY
11743
US
|
Family ID: |
35788353 |
Appl. No.: |
10/587688 |
Filed: |
October 13, 2005 |
PCT Filed: |
October 13, 2005 |
PCT NO: |
PCT/EP05/55228 |
371 Date: |
July 27, 2006 |
Current U.S.
Class: |
15/323 ; 15/347;
15/412 |
Current CPC
Class: |
A47L 9/0009 20130101;
A47L 9/0036 20130101; A47L 9/0027 20130101; A47L 9/242 20130101;
B25H 3/006 20130101 |
Class at
Publication: |
15/323 ; 15/412;
15/347 |
International
Class: |
A47L 9/00 20060101
A47L009/00; A47L 9/22 20060101 A47L009/22; A47L 9/14 20060101
A47L009/14 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2004 |
DE |
10 2004 057 870.2 |
Claims
1. A portable drive unit (10) for operating a handheld power tool
(70) by means of suction and/or blown air, characterized in that it
has a housing (11), which is designed as a case (13) that is
closable with a lid (24), and that its air feeding power is adapted
to the power requirement of the handheld power tool (70), and it
serves to store at least one such or similar handheld power tool
(70), particularly with its accessories, such as air-carrying tubes
and hoses.
2. The portable drive unit (10) as defined by claim 1,
characterized in that its housing (11) is designed as a rectangular
case, with outward-curved edges, rounded corners, and a flat lid
(24) curves inward in dishlike fashion, as well as with a flat
underside and top side (15, 25).
3. The portable drive unit (10) as defined by claim 1,
characterized in that its housing (11) comprises a case part (13),
open at the top, which is openable and closable at the top by means
of a lid (24) that in particular is hinged about a hinge region
(26).
4. The portable drive unit (10) as defined by claim 3,
characterized in that the lid (24) is formed of two parts (23, 27),
of which one flat outer lid shell (23) has a central opening (280),
which is spanned by a strutlike bridge (28) and has curved edges
and corners, and an inner lid shell (27) engages the opening (280)
from below and has a spacing toward the bottom from the strutlike
bridge (28).
5. The portable drive unit (10) as defined by claim 1,
characterized in that a side face (16) of the case (13) has at
least one, in particular mushroom-shaped protrusion (38), around
which a power cord (42) can be wound and thus retained, and the
protrusion (38) forms a parking face on which the drive unit (10)
can set down and at the same time forms an impact face, for
absorbing unwanted impacts for instance in heavy-duty construction
site operation, on a hinge region (26) of the lid (24).
6. The portable drive unit (10) as defined by one of the claim 1,
characterized in that elements for firmly holding the handheld
power tool (70), in particular elastic elements for firm holding
and clamping, preferably in the form of inflatable air cushions,
are located in the case (13).
7. The portable drive unit (10) as defined by claim 1,
characterized in that on one of the two shorter side faces (18, 20)
of the case (13), suction and blower openings (32, 33) with means
for coupling a suction hose (78) are located, in particular side by
side.
8. The portable drive unit (10) as defined by claim 1,
characterized in that the case (13) comprises a case skeleton (22),
which forms riblike reinforcing parts.
9. The portable drive unit (10) as defined by claim 1,
characterized in that recesses (69) on the reinforcing parts are
provided, which are closable by means of attachable elastic shells
(19, 21) of softer, less-expensive material.
10. The portable drive unit (10) as defined by claim 1,
characterized in that hand-actuatable parts, such as lid closure
buttons and a sealing lid, have a contrasting color compared to the
housing (11).
11. The portable drive unit (10) as defined by claim 1,
characterized in that the case (13) has at least one vertical
partition, which in the housing (11) forms a storage compartment
(63) for the handheld power tool (70).
12. The portable drive unit (10) as defined by claim 1,
characterized in that characterized in that the two cases (55, 62),
located side by side and in particular integrated with the case
(13), in particular each having its own lid (48, 61), are closable,
preferably in interlocking fashion, receive the motor (105), and
act as a dust box.
13. The portable drive unit (10) as defined by claim 1,
characterized in that the two cases a motor case (62) and a dust
box (55) with dust monitoring means.
14. The portable drive unit (10) as defined by claim 1,
characterized in that located on the inside of the lid (24) are
retaining means (94) for receiving the suction hose (78), and these
means are locatable in overlooking fashion, spirally, parallel to
the lid (24).
15. The portable drive unit (10) as defined by claim 1,
characterized in that a bypass valve (50) is located on the dust
lid (56).
16. The portable drive unit (10) as defined by claim 1,
characterized in that sealing means are located between the lids
(24, 56, 61) and the case (13, 55, 62).
17. The portable drive unit (10) as defined by claim 1,
characterized in that located in the interior of the drive unit
(10), in particular in the storage compartment (63) or in the
interior of the lid (24), are lighting means, in particular with
LEDs and/or in the form of a fluorescent written marking.
18. The portable drive unit (10) as defined by claim 1,
characterized in that hand-actuatable user control elements (30,
31, 34), particularly for opening and closing a lid or for
actuating a switch button for turning the drive unit on or off, are
located inside the outer contour of the housing (11).
19. The portable drive unit (10) as defined by claim 1,
characterized in that the switch button (34) for turning the drive
unit on or off is accessible from outside for foot- or
hand-operated control via an opening (29) in the lid (24).
20. The portable drive unit (10) as defined by claim 1,
characterized in that a blower adapter (83) is located in fixable
fashion on the blower opening (33) and is replaceable by a blower
grille (46), in particular having a dust filter (44).
21. The portable drive unit (10) as defined by claim 1,
characterized in that an adapter for the suction hose (78) is
provided, with which the hose can be coupled to handheld power
tools, such as electric handheld oscillating sanders, with a
suction stub of a different diameter from the suction hose
(78).
22. The portable drive unit (10) as defined by claim 1,
characterized in that an intermediate hose coupling (91) is
provided, for coupling the suction hose (78) to an extension piece
for the suction hose.
Description
[0001] The present invention is based on a portable drive unit for
handheld power tools driven by suction and/or blown air.
PRIOR ART
[0002] Compact shop vacuum cleaners are known from US 2003/0208874
A1 and European Patent Disclosure EP 1 382 285 A2, which serve as a
cleaning tool and are provided with various accessories for
vacuuming up dust, chips and the like as well as liquids, and which
are furthermore usable in the blower mode as well.
[0003] From International Patent Disclosure WO 03/026841 A1, a tool
case is also known which contains a vacuum cleaner unit for picking
up chips and dust. The known vacuums or tool cases are only
conditionally suitable as a drive unit and carrying box for
suction- or blown-air-operated handheld power tools.
ADVANTAGES OF THE INVENTION
[0004] By the present invention having the characteristics of claim
1, a compact portable drive unit has been created which can be used
both alone as a vacuum cleaner and for driving air-drivable tools,
especially handheld power tools, with simultaneous vacuuming of
dust while these tools are in operation, and which serves as a
carrying box for preferably a plurality of various handheld tools
and with them forms a system for various processing methods that
can be performed with either suction or blown air or both.
[0005] Because the drive unit has a housing which is designed as a
case that can be closed with a lid and whose air feeding power is
adapted to the power required by the handheld power tool and at the
same time serves to store at least one handheld power tool,
especially with accessories as well as air-carrying tubes or hoses
whose diameter is approximately 40 mm, a novel handheld power tool
system is created that operates without connecting the handheld
power tool to electrical current directly and that furnishes enough
working power and suction power.
[0006] Because it has a housing that is designed as a rectangular
case with outward-curved side faces, rounded corners and edges, and
a flat top side and underside, especially with a lid curved inward
in dishlike fashion in the middle with a strutlike handle, an
especially conveniently and handily transported drive unit for
air-driven hand tools is created.
[0007] Because its housing comprises a case part, open at the top,
which is closable there by means of a lid that in particular is
hinged about a hinge region, handheld power tools stored in it can
be stowed in especially good order and easily removed.
[0008] Because the lid is formed of two shells, of which the upper
shell comprises especially bending-resistant, impact-proof material
and has a central opening with a strutlike bridge as well as
downward-bent, curved outer edges and corners, and of which the
lower shell comprises more-elastic, softer material and fits over
the central opening in the upper shell and protrudes, curved
downward, from the strutlike bridge, an especially stable container
part that protects what is being carried against impact from
outside but simultaneously embraces it gently on the inside is
created.
[0009] Because one side face of the case part has at least one, in
particular mushroom-shaped protrusion about which a power cord,
intended for supplying current to the electric motor, can be wound,
and the at least one protrusion acts as a parking face, on which
the drive unit can be set down and at the same time acts as an
impact face for absorbing unwanted impacts in heavy-duty
construction site operation that act on a hinge region of the lid,
the product being carried is accommodated in a way that is
especially securely protected.
[0010] Because retaining/clamping elements are provided in the case
part for accommodating the handheld power tool, and in particular
for firmly retaining and/or clamping it in a prestressed manner,
these elements in particular being in the form of inflatable air
cushion elements, the handheld power tool can be carried in such a
way that it is protected against uncontrolled motion of its own or
relative motion in the interior of the case part when the drive
unit is being carried and thus also is protected against
damage.
[0011] Because one air inlet and one air outlet opening, with means
for coupling a hose, are located side by side each on one of the
two shorter side faces of the case part, then depending on the
choice of handheld power tool to be connected, a fast, convenient
change of the operating setting of the drive unit from the suction
mode to the blower mode is possible.
[0012] Because skeleton-like reinforcing parts that support the
edges are provided in the lower case part, in form of framelike
base parts, onto which more soft-elastic lateral shells can be
constructed, shock-absorbing regions of the housing that comprise
expensive, heavy material can be created with economy of material,
and surfaces less subject to shock comprise the lighter-weight,
less-expensive material and at the same time thus improve shock
absorption toward the inside.
[0013] Because recesses are provided on the reinforcing parts onto
which the shells can be constructed, the weight of the housing can
be kept low.
[0014] Because movable parts, intended for operation by hand, such
as lid closure buttons and a sealing lid for air entry are kept in
a contrasting color compared to the color of the portable drive
unit, they can be found especially quickly and conveniently.
[0015] Because the case part has at least one vertical partition,
which separates the vacuum cleaner and the storage space from one
another, the handheld power tool and its accessories can be stowed
especially logically and securely.
[0016] Because the unit comprises two cases located side by side
that in particular are integrated with the case part and that in
particular each have one lid, are closable, preferably in
overlooking fashion, the housing structure is rigid, and objects
stowed in it are located in a secure, protected way.
[0017] Because the two cases of the vacuum cleaner are designed as
a motor case and a dust box with a dust monitoring opening, they
and their contents are securely protected, independently of one
another, from outside especially against twisting in the event of
shock and impact on the housing.
[0018] Because detent clamping means for a suction hose are located
on the inside of the lid, and the suction hose is designed in
overlooking fashion, spirally placed/located parallel to the lid
face, the hose is stowed in an especially space-saving and handy
way.
[0019] Because a bypass valve is located on the dust lid, the
vacuum cleaner unit is protected against an overload.
[0020] Because sealing lips are located between the lid and the
case part, the entry of air from outside and the escape of dust are
reliably precluded.
[0021] Because black reinforcing parts embrace the green/blue case
part/lid part, the softer and harder regions of the housing can be
distinguished intuitively from one another.
[0022] Because lighting means are located in the interior of the
drive unit, especially in the case part/lid part, these means in
particular having LEDs and/or being in the form of graphical
characters and/or symbols, preferably a fluorescent written
marking, especially good monitoring of the contents in the storage
compartment of the case part at a given time is possible.
[0023] Because the outer faces of user control elements,
particularly for opening and closing a lid or for actuating a
switch button for turning the drive unit on or off, are located
inside the outer contour of the housing, they or the contents
stowed therein are protected against unintentional opening or
damage while being carried.
[0024] Because the switch button for turning the drive unit on or
off is accessible from outside for foot- or hand-operated control
via an opening in the lid, both when the lid is closed and when it
is open, turning the drive unit on and off is possible especially
conveniently, simply, and safely.
[0025] Because a hose adapter is located on the air outlet in such
a way that it can be snapped in place and can be replaced with a
blower grille, in particular with a dust filter, in a firmly
retainable way, the change between the blower and the suction
mode--and vice versa--can be made especially quickly.
[0026] Because a replaceable adapter for the suction hose of the
drive unit can be replaced with a suction extraction adapter,
intended predominantly for vacuum cleaning, especially for dust
extraction in electric tools, the drive unit is usable,
conveniently and with minimal conversion time, as both a vacuum
cleaner and as a suction extractor for electric power tools. The
air stream can be used for driving the handheld power tools and for
simultaneous suction extraction or blowing of dust, chips, and so
forth.
[0027] Because an intermediate coupling piece for attaching an
additional suction hose piece is located on the suction hose of the
drive unit, the suction hose can be lengthened as needed.
[0028] The user thus has the capability of using the drive unit for
different hand-held power tools that are driven with suction and/or
compressed air and that require no direct power supply of their
own.
DRAWINGS
[0029] The invention is described in further detail below in terms
of one exemplary embodiment in conjunction with the drawings.
[0030] FIG. 1 shows a three-dimensional view of the drive unit
obliquely from the front;
[0031] FIG. 2 shows the drive unit obliquely from behind;
[0032] FIG. 3 shows the drive unit of FIG. 1 obliquely from above
with the lid open;
[0033] FIG. 4 shows the drive unit of FIG. 1 obliquely from the
left;
[0034] FIG. 5 shows the drive unit of FIG. 3 with a hose put in
place in spiral form;
[0035] FIG. 6 shows a suction-operated handheld power sander for
operation with the drive unit;
[0036] FIG. 7 is an exploded view of the drive unit;
[0037] FIG. 8a shows a hose coupling for attaching the suction hose
to the drive unit or to an air-driven handheld power sander;
[0038] FIG. 8b shows a top plate with a connection stub for
connecting the hose to the blower opening;
[0039] FIG. 8c shows a coupling piece for connecting the suction
hose to an electric handheld power tool, with a connection stub for
a 19-millimeter hose;
[0040] FIG. 8d shows a coupling piece for connecting the suction
hose to an electric handheld power tool, with a connection stub for
a 35-millimeter hose;
[0041] FIG. 8e shows an intermediate hose coupling for attaching an
extension piece and the suction hose; and
[0042] FIG. 8f shows a drilling aid for a hand power drill for
suction extraction of drilling dust at its site of origin.
DESCRIPTION OF THE EXEMPLARY EMBODIMENT
[0043] The three-dimensional view shown in FIG. 1 of a caselike
drive unit 10 obliquely from the front shows its longitudinal axis
12, which extends parallel to the front side 14 and back side 16.
The lower region of the drive unit 10 is a six-sided, block-shaped
case 13, open at the top, which is closed on its underside 15 by
means of a bottom 17. The case 13 also has a left and right side
18, 20, a and a top side 25, which is embodied by the lid 24.
[0044] The case 13 is formed by a chassislike skeleton case 22 of
impact-proof high-quality material, which has a left and a right
side shell 19, 21 of comparatively elastic, lightweight material
and the pivotably supported lid 24 hammered on on the hinge side
25, the lid forming the top side 26 of the drive unit 10.
[0045] The lid 24 comprises a lid frame 26, which like the skeleton
case 22 comprises impact-proof, high-quality material and on which
a lid shell 27 that is concave--when seen from above--is secured.
The lid frame 26 forms a central handle piece 28, which can be
conveniently grasped with the hand and assures good, balanced
carrying of the drive unit 10.
[0046] Two snap closures 30, 31 are located on the front side 14 of
the case 13, at the top, adjacent to the lid 24, and with them the
lid 24 on the case 13 can be closed securely against unintentional
opening.
[0047] On the left side 18, a suction opening 32 and a blower
opening 33 pass parallel to one another through the left side shell
19.
[0048] On the top side of the case 13, in the corner between the
left side 18 and the back side 16, there is a switch button 34,
which is held elastically prestressed in its outset position by
means of a spring system 35, and from that position it can be
pressed from above into the on or off position. The switch button
34 passes through a fitting opening 29 in the lid 34, so that its
outer face extends flush with the outer face of the lid 24, and
even when the lid 24 is closed, this switch button can be actuated
from outside by foot or with a hand. The switch button 34 is seated
on an upper part 36, which is connected in actuating fashion to a
switch 37.
[0049] On the back side 16, there is a cord post 38 for holding a
power cord 42 that can be wound around it and that emerges, through
a watertight outlet opening not identified by reference numeral in
the back side 16 and can be coupled electrically in the interior of
the case 13 to a motor 104 via a cord clamp 39. In the interior of
the case 13, there is a cord harness 40, which connects the switch
37 to the motor 104 and to other electrical elements that are not
shown.
[0050] A cord holder 41 can be firmly clamped to the edge of the
cord post 38, and with this holder the free end of the power cord
42 can be clamped firmly but removably to it.
[0051] Between a motor case lid 61 and a motor case 62 for
receiving the motor 104 for driving a suction fan, not identified
by reference numeral, there is a motor case seal 42.
[0052] The suction opening 32 is closable by means of a removable
suction lid 48, which prevents dust and chips from its dust box 55
from being able to fall out while the drive unit 10 is being
carried. The blower opening 33 is covered by an outlet filter 44
which is firmly retained on it by means of an outlet grille 46
there.
[0053] The dust box 55 is closable essentially in airtight fashion
by a dust lid 56 by means of a dust seal 57; the dust lid 56 can be
conveniently opened or closed by means of a latchlike protrusion
49. In the dust lid 56, there is a bypass 50, which if the dust box
55 is overfilled opens a valve 53, by way of which air enters,
bypassing the suction opening 32. The bypass 50 comprises a
fixation lid 51, which carries the valve 53 and a seal 52; the
valve 53 is kept prestressed by a spring 54 and does not open and
allow additional air in until beyond a minimum underpressure.
[0054] The motor case 62 is joined to the dust box 55 through a
common opening, which is covered by an intake filter 54. The intake
filter 53 prevents aspirated air chips and dust from reaching the
motor 105.
[0055] The motor case lid 61 is pivotable about a hinge, not shown,
for opening and closing purposes. On the side diametrically
opposite the hinge, it is provided with a finger grip 60, into
which the fingers of one hand can be placed in a gripping manner
for opening the motor case lid 61.
[0056] The snap closures 30, 31 comprise two toggle levers 64, 65,
which are each pivotable about a respective axis 68 by means of a
respective tensing button 66 and a respective detent lever 67. Thus
the lid 24 is closable--pivotable about a hinge side 26--relative
to the case 13 in a way that is secure against unwanted
opening.
[0057] FIG. 2 shows the drive unit 10 obliquely from behind,
looking toward the back side 16; the cord post 38 with the cord
holder 41 are clearly visible. It can also be seen that the face of
the cord post 38 is so large that it can act as a parking face for
setting down the drive unit. The shell-type construction of the
housing 11 of the drive unit 10 can also be seen, along with the
disposition of the suction and blower openings 32, 33.
[0058] FIG. 3 shows the drive unit 10 of FIG. 1 obliquely from the
top with the lid 24 open, looking into its interior. The intended
spiral arrangement of the suction hose 78 to be put in place and
the design of the retaining and clamping elements 45 for receiving
it in the lid 24 are visible. Moreover, the top view on the case
13, switch button 34, opening 29 in the lid 24 for the passage
through it of the switch button 34, the latch 49 for
pivoting/opening the dust lid 56 about its hinge 560, the bypass 50
seated on it, the finger grip 60 for opening the motor case lid 61,
a storage compartment 63 for accommodating a delta sander 70 and
accessories 98 are all shown. It can be seen that approximately
half the volume of the case 13 is available for accommodating the
delta sander, and the entire volume of the lid 24 is available for
accommodating the suction hose 78.
[0059] FIG. 4 shows the drive unit 10 obliquely from above looking
toward the left side 18 with the suction opening 32 and the blower
opening 33 and toward the front side 14 and the top side 25; the
details described above are clearly shown and need not be
repeated.
[0060] FIG. 5 shows the drive unit 10 with the suction hose 78
placed in a spiral on the inside in the open lid 24, similarly to
FIG. 3, but the accessories 98 are different.
[0061] FIG. 6 shows a suction-operated handheld power sander
designed as a turbine delta sander 70, for operation with the drive
unit 10. The handheld power sander has a housing 71 shaped like an
iron for clothing, with an upper region that can be grasped by the
hand and that serves as a guiding handle 72. Toward the back, the
housing 71 continues in the form of a tubular housing region 73
which serves as a main handle that is conveniently grasped by the
hand that operates the tool.
[0062] This main handle opens into a coupling stub 80, into which a
hose coupling piece 81 of the suction hose 78 can be inserted in
overlooking fashion for connecting the delta sander 70 to a drive
unit 10 for operation with suction. At the top in the region of the
guiding handle, a switch button 74 is located, with which the flow
of suction can be reduced. With the suction, a turbine, not shown,
in the interior of the housing 71 that sets a sander plate 76 into
orbital motion is driven.
[0063] The house coupling piece 81 is connectable in form-locking
and overlooking fashion to the coupling stub 80 via detent cams 82,
and there it enters into detent openings, not identified by
reference numeral, in the wall of the coupling stub 80.
[0064] FIG. 7 shows an exploded view of the drive unit 10--broken
down into its individual parts. The details and characteristics
described in conjunction with the previous drawings are shown
especially clearly.
[0065] FIG. 8a shows a hose coupling for attaching the suction hose
to the drive unit 10 or to a delta sander 70 or similar air-driven
handheld power tool.
[0066] FIG. 8b shows a blower adapter 83, which comprises a top
plate 100 that is provided with a connection stub 101, which serves
to connect the suction hose 78 to the blower opening 33, and this
opening can be replaced for the outlet grille 46 with the outlet
filter 44 for the suction mode.
[0067] To that end, the top plate is provided on its lateral ends
with detent tongues 84, which can be clipped onto the left side 18
on the outside in the region of the blower opening 33.
[0068] FIG. 8c shows a hose coupling piece 85 for connecting the
suction hose 78 to a slender (19 mm) suction hose connection/waste
air stub of an electric handheld power tool that produces a medium
to a large amount of dust.
[0069] FIG. 8d shows another coupling piece 88 for connecting the
suction hose 78 to a somewhat less-slender (35 mm) suction hose
connection of an electric power tool that produces a medium to a
large amount of dust.
[0070] FIG. 8e shows an intermediate hose coupling 91 for coupling
a suction extractor hose lengthening piece, whose diameter matches
that of the suction extraction hose 78.
[0071] FIG. 8f shows a drilling aid 93 for passing through a drill
for suction extraction of the drilling dust produced in
drilling.
[0072] Upon connection to the suction opening 32, the drive unit 10
can drive the following devices by suction, for instance, and
simultaneously extract the dust and dirt produced by suction, dust
and dirt that is filtered out by an arbitrary filter system:
oscillating/multisander, eccentric sander, plaster cardboard
cutter, drilling aid.
[0073] On being connected to the blower opening 33, the drive unit
10 can operate the following devices with the "compressed" air
flow: paint spray gun, blower nozzle/joining nozzle, hot-air gun,
valve attachment for inflating inflatable rafts and air mattresses,
etc.
[0074] In the case 13 of the drive unit 10, there is a storage
compartment 63 for the delta sander 70 and suction function
accessories, such as a joining nozzle, drilling aid 93, adapter for
power tools 85, 88, adapter for vacuum cleaner accessories,
sandpaper (Z), or the like.
[0075] The power cord 42 is wound around the cord post 38 on the
back side 16 of the drive unit 10 and secured to the cord post 38
with a cliplike cord holder 41. The cord post 38 can also be used
as a parking face for stowing the drive unit 10 upright.
[0076] The blower adapter 83 for replacement with the blower grille
44 serves to provide improved air throughput in the suction mode
and better pressure buildup in the blower mode.
[0077] The suction hose 78 has a coupling stub 80, acting as a
fast-action coupler, with which it can be connected to vacuum
cleaners, turbine delta sanders, or other associated devices.
[0078] The switch button 34 on the upper edge/corner makes it
possible to turn the device on and off conveniently using the foot,
and to turn the device on and off either with the lid open and with
the lid closed.
[0079] The case 13 stiffened with side shells 19, 21, which are
braced against and/or screwed to the skeleton case 22. Only by
using a stiffer/higher-quality material for part of it can the
strength of the skeleton case 22 be increased without having to use
the more-expensive material for the entire housing 11.
[0080] Both the suction opening 32 and the blower opening 33 with
finger depression are integrated into one side shell 19, so that in
that location there is great freedom of design with simpler
unmolding of the injection-molded part.
[0081] The lid shell 23 is likewise located, in the form of a
concave insertion part, centrally in the handle region of the
handle piece 28 in the flat lid 24. As a result, this region can be
better unmolded from the injection molding tool; the stackability
of the drive unit is assured, and upon use, the storage place for
small parts or tools with the lid closed is assured and is used as
a design element.
[0082] The bypass valve 50 in the dust lid 56 are alternatively in
the filter housing assures that the motor 104 will not run at an
overload when the dust bag is added. The motor is cooled with the
suction. If the dust bag is full of the ground material, or its
pores have become clogged, the remaining cooling air can no longer
cool the motor 104 adequately without a bypass valve 50. The motor
would then overheat. The underpressure/bypass valve 50 opens as
soon as the underpressure in the filter space between the dust
filter and the motor fan, drops below a defined value, which can be
set via a spring 54. By opening the bypass valve 50, air is
additionally aspirated, bypassing the filter, for adequately
cooling the motor [7].
[0083] When the drive unit 10 is being carried, the escape of dust
and dirt from the suction opening 32 is prevented by the
disposition of the suction lid 48. Opening is made easier by a grip
depression in the side part [24], and loss is prevented by
fastening with a pin to the side part [24].
* * * * *