Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DEVICE FOR CONVERTING ELECTRIC ENERGY INTO A MECHANICAL ONE
AND/OR FOR DOING THE OPPOSITE AND METHOD FOR PRODUCING SUCH A
DEVICE
The invention relates to a device for converting electric energy into
mechanical energy and/or the
opposite according to the disclosure part of Claim 1 as well as a method for
producing such a
device.
A device as in the disclosure part of Claim 1 is known from EP 0 213 863 A2.
This document
shows a device connecting the winding ends of an electric motor, which is
arranged in the form
of an annular sheet bar with circumferential conductor paths and solder-
connection surfaces at
one axial end of the electric motor. The conductor paths and with them the
winding ends can be
contacted from the exterior either by connection pins projecting from the
sheet bar or by means
of connection conductors to be soldered to other solder-connection surfaces.
In the case of other known devices the ends of the windings which are the coil
windings of the
rotor and/or the stator stand at some acceptable distance over the coil
windings and are guided in
circumferential direction relative to a common point. There, the relevant ends
of the windings
are pressed together with one another, thus forming groups of connections, and
then are provided
with an electrical connection element. This requires costly and essentially
manually executable
laying out of the winding ends and also increases the dimensions of the
structure, since the
winding ends must be guided over the coil windings. Also, the connection
between the
connection device and the pressed-on winding ends, especially under
environmental conditions
which generate reactions thereto, represents a possible source of breakdown
during operation of
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the device which has been produced, for example because of corrosion of the
contacts.
EP 0 863 601 A1 shows a connection device for a stator in which connection
wires forming
connection distributors and being electrically insulating are embedded in
circumferential grooves
of an end plate fastened securely at the end of the stator. The ends of
adjacent connection wires
of the same group of connections which are turned toward one another are in
turn pressed
together with an associated winding end of the coil winding of the associated
group of
connections. To each connection distributor is guided a connection wire of the
electric contact
mechanism on the exterior of the device.
JP 6-233 483 A likewise shows a connection device for the electric connection
of the winding
ends of a group of connections of stator coil windings.
WO 97/26700 shows a connection device of a vehicle motor having connection
plates of
nonagon, annular format, arranged one over the other, to which the winding
ends of the coil
winding can be welded and which in turn have a crimp-connection for the crimp-
connecting with
a connection conductor leading toward the exterior. Each connection plate
consists of a first
electrically conductive layer and a second electrically insulating layer.
DE 195 44 830 Al shows a stator for electric motors in which the winding ends
of a connection
group are connected with one another by electrically conducting connection
distributors running
in circumferential direction. The connection distributors have connection
soldering lugs to
which the winding ends or the motor connection conductors are welded or
soldered.
US 4,224,543 shows a connection device for winding ends of stator coil
windings with a sheet
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bar
having radial notches to receive the ends of the winding and of external
connection conductors,
which subsequently are to be soldered with connection surfaces of the
conductor paths mounted
on the sheet bars.
US 5,806,169 shows a method for the production of an electric motor in which
the stator is
spray-injected and injection molded following the welding of the stator
windings onto
corresponding connection soldering lugs by means of an injection molding
technique using a
synthetic resin material.
The object of the invention is therefore to disclose a device to overcome the
problem by using
such a device, and an associated method of production of the device, which
method and device
overcome the drawbacks of the state of the art, particularly by incorporating
small structural
dimensions which guarantees high contact reliability with simple contacting
and a long life and
high current carrying capacity even under aggressive environmental conditions,
and which can be
manufactured simply.
The problem is solved by the device disclosed in Claim l, as well as by the
method which is
disclosed in the other claims. Particular embodiments of the invention are
disclosed in the
dependent claims.
The device according to Claim 1 can be a motor or a generator, particulary a
combined
alternating or direct current-powered motor/generator device. Thus, coil
windings could be
arranged both on the rotor and on the stator, corresponding to the number of
poles found on the
device. The switch connection of the individual winding ends occurs according
to the invention
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by means of a connection device with formation of connection groups or contact
groups. With a
three-phase alternating current device, for example, three (delta-wound
circuit), four (star-wound
circuit with spread-out star) or six connection or contact groups are formed.
With six groups of
connections, a switchover from star operation to three-phase operation and
vice versa can also
occur outside the device by suitable switching of the groups of connections.
The rotor can be
running on the interior or on the exterior in relation to the stator. A rotor
having identical mass
and running on the exterior has greater moments of inertia and torque. The
connection
distributor is guided toward the outside of the rotor or stator and there
forms one piece with a
connection device. This occurs preferably by suitable bending or shaping of a
copper band or
strip serving as connection distributor to a mechanical sleeve or bearing or
plug element.
According to the one particular embodiment disclosed in Claim 2, the winding
ends could
advantageously be quite short. This leads not only to savings of material but
also to small
structural dimensions for the entire device. In the case of a rotor winding
the rotor then has a
slight imbalance which is a condition of this the type of construction.
According to the particular embodiment as in Claim 3, the connection
distributors which may be
annular in construction have cutting/clamping devices of one integral piece on
the corresponding
points at which the winding ends can be embedded, whereby the winding
insulation is cut
through at those points upon the pressing in of the winding ends. The
cutting/clamping device in
turn is preferably arranged precisely in relation to the associated winding
ends. The
cutting/clamping device can be set up ready for use by corresponding provision
of a copper strip
or copper ring to be used as connection distributor.
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The particular embodiment of Claim 4 provides the two bands in essentially
circular and coaxial
alignment with the stator/rotor axis. Preferably a copper band or a copper
strip is provided as
connection distributor, whereby the band or strip is aligned parallel to the
rotor or stator axis.
The two bands or strips are guided in one piece toward the exterior of the
device and there form a
bushing area for the connection device by means of complementary semi-circular
bends. In the
bushing area the band or strip width is aligned parallel to the longitudinal
axis of a plug element
to be plugged into the bushing.
According to the particular type of embodiment disclosed in Claim 5, in the
bushing area the two
bands are connected with one another by an elastic element, preferably
connected by a
corrugated retaining ring. A permanent contact reliability is thus guaranteed
along with
simultaneous high current-carrying capacity.
According to the particular type of embodiment disclosed in Claim 6, the
connection distributors
are arranged axially and radially one behind the other, whereupon the radial
and/or axial
structural dimensions of the device can be minimized. The particulars with
reference to radial
and/or axial arrangement are then referenced to the rotary axis of the device.
According to the particular embodiment as in Claim 7, by use of the receiving
means, not only is
an electric insulation of the connection distributors from one another
guaranteed by the receiving
means but also, by the provision of positioning means, for example cams on the
receiving means
and notches on the associated connection distributor, an exact peripheral
positioning of the
connection distributor in relation to the receiving means and correspondingly
in relation to the
device can be guaranteed. Thus, minimal connection paths between the
connection distributes
and the coil winding are guaranteed simultaneously with simple assembly. Of
course the
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connection distributors could also be fastened securely directly to the rotor
and/or the stator
without use of any receiving means.
With the method of the invention as in Claim 8, first of all the electrically
conducting connection
distributors are embedded in receiving means of the connection device, then
the connection
device fastened securely to the rotor or stator for example by bolting or
pinning on, then further
and subsequently the winding ends electrically connected with the associated
connection
distributors and finally in turn a plug bushing of the connection device
formed of one piece with
the bands guided toward the exterior of the device for the electric contacting
of the connection
groups to the exterior of the device. This step of the method could
advantageously be made
automatic and for example could be executed by industrial robots.
According to the type of embodiment disclosed in Claim 9, the winding ends can
be connected
with the associated connection distributors by means of a cutting/clamping
device or by gluing,
soldering or welding. Preferably high temperature-resistant electrically
conductive adhesive
substances are used for glue. Preferably the hard-soldering process is used
for soldering. When
using welding, spot-welding is preferred.
In the type of embodiment of Claim 10, the receiving means are sealed off with
the embedded
connection distributors, if necessary with use of a clamp collar. This
preferably occurs by
dipping in an electrically insulating synthetic resin. Then contact points for
the electric
connection with the ends of the windings remain accessible on the connection
distributors.
Alternatively to that, the contact points of the connection distributor
provided with a
cutting/clamping device could also be cast or filled in, since during the
pressing in of the winding
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ends the insulating layer is penetrated. This use of the procedure
has the advantage that the connection device can be set up as a complete
structural assembly in
and of itself on the rotor or stator and can be completely assembled in one
step.
According to the embodiment of Claim 11 the completely assembled and wired
rotor or stator is
cast in insulating material.
Other advantages, features and individual disclosures of the invention are
disclosed by the
dependent claims as well as the following description, in which a number of
exemplary
embodiments are described in some detail with reference to the attached
drawings. Therefore the
features mentioned in the claims and in the description could in turn be
essential to the invention
in and of themselves or in any desired combination.
Fig. 1 shows a cross section through a device according to the invention,
Fig. 2 shows a plan view of the stator of Fig. 1,
Fig. 3 shows the electric wiring of the coil windings,
Fig. 4 shows a section corresponding to the line IV-IV of Fig. 2,
Fig. S shows a section along the line V-V of Fig. 2,
Fig. 6 shows a cross section along the line VI-VI of Fig. 2,
Fig. 7 shows an alternative embodiment of the device,
Fig. 8 shows an enlarged section of Fig. 7 in the area of the connection
distributors, and
6a
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Fig. 9 shows the view IX of the connection mechanical sleeve or bearing of
Fig. 7
Fig. 1 shows a cross section through a device according to the invention. In
this case it has to do
with a combined motor/generator device 1 with an interior stator 2 and a rotor
4 running on the
exterior around the axis 3. The traditional associated housing is not shown.
On the tin-plated
core S of stator 2 are wound in sequence coil windings 6 in circumferential
alignment. The
winding ends of the various coil windings are connected electrically with one
another with
formation of groups of connections, whereby a connection device 7, 8, 9, 10
includes connection
distributors 8, 9, 10 running in circumferential alignment, which are inserted
in receiving means
which can be fastened and sealed onto rotor 2. Connection distributors 8, 9,
10 of each group of
connections are formed in the present embodiment by two copper bands bent in
approximately
semi-circular shape, which are arranged one behind the other in radial
direction 20 and are
electrically insulated from one another. The copper bands are dimensioned to
correspond to the
electric currents to be supported, for example they are of a width x thickness
of 15 X 1 mmZ~.
Rotor 4 running on the exterior engages peripherally around the stator and
supports permanent
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magnets 12 on the surface 11 facing stator 2 in a number corresponding,to the
number of poles or
the number of coil windings 6. Coil windings 6 if necessary can also have one
or more
symmetrically or unsymmetrically distributed partial taps.
Fig. 2 shows a plan view of the stator 2 of Fig. 1. Of the coil windings 6
arranged over the entire
circumference in circumferential direction 13 there are represented for
clarity only six coil
windings 6a, 6b, 6c. The stator 2 which is represented is wired for a three-
phase alternating
current connection in a triangular circuit.
Coil windings 6a, 6b, 6c are thus wired each by means of approximately semi-
circular
connection distributors 8a, 8b; 9a, 9b; 10a, l Ob to three connection groups
and can be electrically
connected from outside the stator by means of a first, second and third
mechanical sleeve or
bearing 14, 15, 16. The first winding end 17a of coil winding 6a of the first
group of connections
is connected with connection distributor 8b, whereas the second winding end
17b is connected
with connection distributor 9b. The first winding end 18a of coil winding 6b
of the second group
of connections is connected with connection distributor 9b, whereas the second
winding end 18b
is connected with connection distributor lOb. The first winding end 19a of
coil winding 6c of the
third group of connections is connected with connection distributor l Ob, and
the second winding
end 19b is connected with connection distributor 8b. And so forth, for the
connection of the
corresponding winding ends to connection distributors 8a, 8b; 8c. Both of the
connection
distributors 8a, 8b are formed in turn by copper strips which are bent
approximately in semi-
circles made up of one piece at one point of the circumference upward and/or
outward and the
corresponding ends are bent into formation of a mechanical sleeve or bearing
area for an electric
connection 14 of this connection group. Correspondingly the same is the case
for the two
connection distributors 9a, 9b, which in one piece form the connection 15 of
the second
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connection group, and for connection distributors 10a, l Ob, which in one
piece form the electric
connection 16 of the third connection group.
Fig. 3 shows the electric wiring of the coil windings 6a., 6b, 6c of Fig. 2,
arranged alternating in
circumferential direction, which are connected parallel within the groups of
connections which
are formed and as a whole are wired to a three-phase, delta-wound circuit with
the three electric
connections 14, 15, 16. Insofar as a three-phase-star circuit is required,
four connection groups
altogether are provided, whereby the star point as needed can be guided over a
fourth connection
toward the outside of the stator or not. If the possibility of reversal from
star- to delta-wound
circuit and vice versa is to be present, the two winding ends of the parallel-
connected coil
windings in turn are to form contacts by connection distributors insulated
from one another and
are to lead to six electric connections in all.
Fig. 4 shows a section corresponding to line IV-IV of Fig.. 2. The first end
18a of coil winding
6b wound on laminated core 5 is connected electrically with the middle of
connection distributor
9a in radial direction 20 by means of a cutting/clamping device 21 configured
in one piece
therewith. With the pressing in of the insulated winding end 18a the
insulation is penetrated by
the cutting flank 21 a and the electric contact between connection distributor
9a and winding end
18a is produced. With further pressing in of winding end 18a, the cutting off
of the nearly flush
winding wire occurs. In the area of the connection of winding end 18a to
connection distributor
9a the connection distributor 8a on the exterior in radial direction 20
preferably has a notch, in
order to guarantee an electrically insulated passage of winding end 18a to the
middle of
connection distributor 9a in radial direction 20. Alternatively or in
supplement hereto, the
exterior connection distributor 18a can also have a narrower strip width over
its entire length
and/or can be inserted more deeply into the receiving means 7, which for
example is formed by a
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plastic ring provided with grooves to receive said connection distributors 8a,
8b, 9a, 9b, 10a, lOb.
Fig. 5 shows a section along line V-V of Fig. 2. Both of the approximately
semi-circular
connection distributors 9a, 9b according to Fig. 2 are bent radially outward
in the area of section
V-V in electric contact with one another. In the area of bringing together of
the two connection
distributors 9a, 9b, the exterior connection distributor 8a aligned in radial
direction has a notch,
so that connection distributor 9b can be guided past electrically insulated
therefrom.
Fig. 6 shows a cross section along line VI-VI of Fig. 2. The two connection
distributors 8a, 8b
bent semi-circular at this point come in contact with one another on the
circumference and are
guided together toward the exterior of stator 2. By means for example of a not
shown projection
provided in the overlapping area, the projection on connection distributor 8a
and a convexity
provided at the corresponding point of connection distributor 8b, during the
insertion and guiding
together of the connection distributors 8a, 8b, a simple and precise
positioning of connection
distributors 8a, 8b in relation to receiving means 7 and in relation to one
another is guaranteed.
Instead of projection and convexity for example also a sort of groove/spring
combination in the
associated connection distributors 8a, 8b; 9a, 9b; 10a, l Ob could be
provided.
Fig. 7 shows an alternative embodiment of the device of the invention, whereby
an interior stator
102 is again provided, this time with coil windings 106 -here shown only
diagrammatically. The
connection distributors 108, 109, 110 connected electrically with one another
in this embodiment
are arranged one behind the other in axial direction 122 parallel to the
rotation axis 103 of the
associated and not shown rotor and are electrically insulated from one another
by receiving
means 107. Fig. 8 shows a cutout enlargement of Fig. 7 in the area of
connection distributors
108, 109, 110. Winding end 118a of coil winding 106b is electrically connected
by means of the
cutting/clamping device 121 with the center of connection distributor 109 in
axial direction 122.
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Fig. 9 shows the view IX of the mechanical sleeve or bearing 116 of the
connection of Fig. 7.
The two upward bent ends 110x, 1 lOb of connection distributor 110 are bent in
the contact area
complementarily and symmetrically to the symmetry plane 123 perpendicular to
the plane of
viewing, symmetry plane 123 being bent in a semi-circle in order to be able to
receive a contact
pin. The ends of connection distributors 110a, 110b are secured flexibly in
the mechanical
sleeve or bearing area by means of a corrugated retaining ring 124.