EP0856384A1 - Handheld power tool with a detector, which gives a service signal when the carbon brushes reach a minimum length - Google Patents

Handheld power tool with a detector, which gives a service signal when the carbon brushes reach a minimum length Download PDF

Info

Publication number
EP0856384A1
EP0856384A1 EP97121395A EP97121395A EP0856384A1 EP 0856384 A1 EP0856384 A1 EP 0856384A1 EP 97121395 A EP97121395 A EP 97121395A EP 97121395 A EP97121395 A EP 97121395A EP 0856384 A1 EP0856384 A1 EP 0856384A1
Authority
EP
European Patent Office
Prior art keywords
brush
brushes
tool according
drive motor
commutator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP97121395A
Other languages
German (de)
French (fr)
Other versions
EP0856384B1 (en
Inventor
Günter Schaal
Martin Gerschner
Werner Renz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0856384A1 publication Critical patent/EP0856384A1/en
Application granted granted Critical
Publication of EP0856384B1 publication Critical patent/EP0856384B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R39/00—Rotary current collectors, distributors or interrupters
    • H01R39/02—Details for dynamo electric machines
    • H01R39/58—Means structurally associated with the current collector for indicating condition thereof, e.g. for indicating brush wear
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25F—COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR
    • B25F5/00—Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for

Definitions

  • the invention is based on a hand machine tool the preamble of claim 1. It is already one Hand machine tool known on the market that has a detector which, when reaching a minimum length l of Carbon brushes generate a service signal. The service signal, which is given by a warning lamp instructs the operator the hand machine tool to the need of Exchange of carbon brushes.
  • a mechanical shut-off device that when a remaining length of the carbon brush is reached, the smaller than the minimum length l is the contacting of the collector prevented by the carbon brush.
  • the detector and that mechanical shut-off device are in the carbon brush integrated.
  • the mechanical shut-off device claims due to the design, a relatively large remaining shutdown length of the entire brush length L.
  • the use of carbon brushes is therefore not in the known hand machine tools particularly good, i.e. the carbon brushes already have to relatively short time intervals are exchanged.
  • the hand tool according to the invention with the features of claim 1 has the advantage that the carbon brushes same brush length L have a longer service life, so that a brush change is less necessary.
  • FIG. 1 shows a longitudinal view of a Rotary hammer as an example of a hand tool
  • Figure 2 is a schematic representation of a carbon brush Detection device.
  • 10 denotes a hammer drill, which as Example of a hand tool according to the invention is used.
  • the handheld power tool has a housing 11 in which a electric drive motor 12 is housed.
  • the Drive motor 12 has a motor shaft 13 on which a pinion 14 is arranged on the output side, via which the Drive motor 12 a transmission and not shown above it drives a tool 15 rotating and / or striking.
  • the drive motor 12 is provided with a collector 18, with its outer circumference two opposite each other arranged brushes 19 in electrically conductive contact stand.
  • a control device 22 is connected via an input line 17 depending on the respective switching position Switch 23 supplied with electrical drive energy.
  • the Control device 22 makes contact via electrical lines 20, 21 the two opposite brushes 19 and controls the electric drive motor 12. Furthermore connect detection lines 24, 25 to the brushes arranged detection devices 26, 27 with the Control device 22.
  • FIG. 2 shows a detection device known per se 26, which is formed on a brush 19, which cooperates with the collector 18.
  • the Detection device 26 is that of collector 18 facing away from the rear of the brush 19 and over the Line 21 connected to the control device 22.
  • the Detection device 26 consists of an isolated Wire piece 30 which is bent into a loop and in the Brush 19 integrated in the rear area, preferably is pressed or sintered therein.
  • Detection device 26 i.e. the wire piece 30 over the To connect conductor 24 to the control device 22.
  • Detection device 26 At Reaching the minimum length l of the brush 19 is due to the damaged insulation of the wire piece 30 from the Detection device 26 generates a detection signal s which via the conductor 24 to the control device 22 is forwarded.
  • the control device 22 changes when the Detection signal s the electrical control of the Drive motor 12 in that the use of Handheld machine tool restricted or even impossible becomes. In this way, the operator is on electronic Paths signals that a change of brushes 19th is required.
  • the change in control can consist, for example, that the drive motor 12 is switched off or only runs slowly, or in Operation is booming.
  • the detection signal s can also to generate a light signal or an acoustic Signals are processed further.
  • a mechanical shut-off device for the brushes is included Handheld power tools equipped according to the invention are not more needed.
  • the detection device 26 has a smaller one Distance l from the back of the brush 19 and therefore increases a significantly smaller proportion of the variable Total length L of the brushes 19 in claim.
  • the available Abrasion length L-l of the brushes 19 is thus lengthened and the service life increases.
  • the invention is not based on the above Embodiment limited. So it is enough one of the To provide brushes 19 with a detection device 26, since the brushes 19 experience fairly evenly be worn out and normally replaced at the same time Need to become.
  • the hand machine tool can also do more than have two brushes 19.

Abstract

The hand power tool has at least two brushes in contact with the commutator. At least one of the brushes is fitted with a detector connected to a control (26) which gives an indication when the brush length has reached a set minimum. The control also reduces the power of the tool to prolong the life of the brushes until they can be changed. The detector comprises a wire embedded in part of the brush and insulated from the material of the brush. When the wire touches the commutator the warning system is activated. The warning can be optic or acoustic.

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Handwerkzeugmaschine nach dem Oberbegriff des Anspruchs 1. Es ist schon eine Handwerkzeugmaschine am Markt bekannt, die einen Detektor aufweist, der bei Erreichen einer Mindestlänge l der Kohlebürsten ein Servicesignal erzeugt. Das Servicesignal, das durch eine Warnlampe gegeben wird, weist den Bediener der Handwerkzeugmaschine auf die Notwendigkeit des Austauschs der Kohlebürsten hin. Zusätzlich ist in die Kohlebürsten ein mechanisches Abschaltorgan integriert, das bei Erreichen einer Restlänge der Kohlebürste, die kleiner als die Mindestlänge l ist, die Kontaktierung des Kollektors durch die Kohlebürste verhindert. Der Detektor und das mechanische Abschaltorgan sind in die Kohlebürste integriert. Das mechanische Abschaltorgan beansprucht jedoch konstruktionsbedingt eine relativ große Abschalt-Restlänge der gesamten Bürstenlänge L. Die Ausnutzung der Kohlebürsten ist daher bei den bekannten Handwerkzeugmaschinen nicht besonders gut, d.h. die Kohlebürsten müssen schon nach relativ kurzen Zeitintervallen ausgetauscht werden. The invention is based on a hand machine tool the preamble of claim 1. It is already one Hand machine tool known on the market that has a detector which, when reaching a minimum length l of Carbon brushes generate a service signal. The service signal, which is given by a warning lamp instructs the operator the hand machine tool to the need of Exchange of carbon brushes. In addition, in the Carbon brushes integrated a mechanical shut-off device that when a remaining length of the carbon brush is reached, the smaller than the minimum length l is the contacting of the collector prevented by the carbon brush. The detector and that mechanical shut-off device are in the carbon brush integrated. The mechanical shut-off device, however, claims due to the design, a relatively large remaining shutdown length of the entire brush length L. The use of carbon brushes is therefore not in the known hand machine tools particularly good, i.e. the carbon brushes already have to relatively short time intervals are exchanged.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Handwerkzeugmaschine mit den Merkmalen des Anspruchs 1 hat den Vorteil, daß die Kohlebürsten bei gleicher Bürstenlänge L eine längere Standzeit aufweisen, so daß ein Bürstenwechsel seltener notwendig ist.The hand tool according to the invention with the features of claim 1 has the advantage that the carbon brushes same brush length L have a longer service life, so that a brush change is less necessary.

Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Anspruch 1 genannten Handwerkzeugmaschine möglich.By the measures listed in the subclaims advantageous developments and improvements in Claim 1 hand tool mentioned possible.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 eine Längsansicht eines Bohrhammers als Beispiel einer Handwerkzeugmaschine und Figur 2 eine schematische Darstellung einer Kohlebürste mit Detektionseinrichtung.An embodiment of the invention is in the drawing shown and in the following description explained. 1 shows a longitudinal view of a Rotary hammer as an example of a hand tool and Figure 2 is a schematic representation of a carbon brush Detection device.

Beschreibung des AusführungsbeispielsDescription of the embodiment

In Figur 1 ist mit 10 ein Bohrhammer bezeichnet, der als Beispiel einer erfindungsgemäßen Handwerkzeugmaschine dient. Die Handwerkzeugmaschine hat ein Gehäuse 11, in dem ein elektrischer Antriebsmotor 12 untergebracht ist. Der Antriebsmotor 12 hat eine Motorwelle 13, auf der abtriebsseitig ein Ritzel 14 angeordnet ist, über das der Antriebsmotor 12 ein nicht näher dargestelltes Getriebe und darüber ein Werkzeug 15 drehend und/oder schlagend antreibt. Der Antriebsmotor 12 ist mit einem Kollektor 18 versehen, mit dessen Außenumfang zwei einander gegenüberliegend angeordnete Bürsten 19 in elektrisch leitendem Kontakt stehen. In Figure 1, 10 denotes a hammer drill, which as Example of a hand tool according to the invention is used. The handheld power tool has a housing 11 in which a electric drive motor 12 is housed. Of the Drive motor 12 has a motor shaft 13 on which a pinion 14 is arranged on the output side, via which the Drive motor 12 a transmission and not shown above it drives a tool 15 rotating and / or striking. The drive motor 12 is provided with a collector 18, with its outer circumference two opposite each other arranged brushes 19 in electrically conductive contact stand.

Eine Steuereinrichtung 22 wird über eine Eingangsleitung 17 in Abhängigkeit der jeweiligen Schaltstellung eines Schalters 23 mit elektrischer Antriebsenergie versorgt. Die Steuereinrichtung 22 kontaktiert über elektrische Leitungen 20, 21 die beiden einander gegenüberliegenden Bürsten 19 und steuert den elektrischen Antriebsmotor 12 an. Darüber hinaus verbinden Detektionsleitungen 24, 25 an den Bürsten angeordnete Detektionseinrichtungen 26, 27 mit der Steuereinrichtung 22.A control device 22 is connected via an input line 17 depending on the respective switching position Switch 23 supplied with electrical drive energy. The Control device 22 makes contact via electrical lines 20, 21 the two opposite brushes 19 and controls the electric drive motor 12. Furthermore connect detection lines 24, 25 to the brushes arranged detection devices 26, 27 with the Control device 22.

In Figur 2 ist eine an sich bekannte Detektionseinrichtung 26 dargestellt, die an einer Bürste 19 ausgebildet ist, welche mit dem Kollektor 18 zusammenwirkt. Die Detektionseinrichtung 26 ist der dem Kollektor 18 abgewandten Rückseite der Bürste 19 angeordnet und über die Leitung 21 mit der Steuereinrichtung 22 verbunden. Die Detektionseinrichtung 26 besteht aus einem isolierten Drahtstück 30, das zu einer Schlaufe gebogen ist und in die Bürste 19 im rückseitigen Bereich integriert, vorzugsweise darin verpresst bzw. eingesintert ist. Beim Betrieb der Handwerkzeugmaschine nutzt sich die Bürste 19 infolge des elektrischen (Bürstenfeuer) und mechanischen (Reibung) Verschleiß am Kollektor 18 ab. Sobald der Abrieb der Bürste 19 bis zur Detektionseinrich-tung 26 fortgeschritten ist, d.h. wenn der Kollektor 18 am Drahtstück 30 reibt und dessen Isolierschicht beschädigt, entsteht zwischen Drahtstück 30 und Bürste 19 bzw. Kollektor 18 eine elektrisch leitende Verbindung. Eine an der Bürste 9 anliegende elektrische Spannung kann dann auf das Drahtstück 30 gelangen und für die Erzeugung eines Detektionssignals s dienen.FIG. 2 shows a detection device known per se 26, which is formed on a brush 19, which cooperates with the collector 18. The Detection device 26 is that of collector 18 facing away from the rear of the brush 19 and over the Line 21 connected to the control device 22. The Detection device 26 consists of an isolated Wire piece 30 which is bent into a loop and in the Brush 19 integrated in the rear area, preferably is pressed or sintered therein. When operating the Hand tool uses the brush 19 as a result of electrical (brush fire) and mechanical (friction) Wear on the collector 18. As soon as the brush abrasion 19 has advanced to the detection device 26, i.e. when the collector 18 rubs on the wire piece 30 and its Damaged insulation layer, arises between wire piece 30 and brush 19 or collector 18 an electrically conductive Connection. An electrical on the brush 9 Voltage can then reach the piece of wire 30 and for serve to generate a detection signal s.

Erfindungsgemäß wird nun vorgeschlagen, die Detektionseinrichtung 26, d.h. das Drahtstück 30 über den Leiter 24 mit der Steuereinrichtung 22 zu verbinden. Bei Erreichen der Mindestlänge l der Bürste 19 wird infolge der beschädigten Isolation des Drahtstücks 30 von der Detektionseinrichtung 26 ein Detektionssignal s erzeugt, das über den Leiter 24 an die Steuereinrichtung 22 weitergeleitet wird.According to the invention it is now proposed that Detection device 26, i.e. the wire piece 30 over the To connect conductor 24 to the control device 22. At Reaching the minimum length l of the brush 19 is due to the damaged insulation of the wire piece 30 from the Detection device 26 generates a detection signal s which via the conductor 24 to the control device 22 is forwarded.

Die Steuereinrichtung 22 verändert bei Vorliegen des Detektionssignals s die elektrische Ansteuerung des Antriebsmotors 12 dahingehend, daß die Benutzung der Handwerkzeugmaschine eingeschränkt oder sogar unmöglich wird. Auf diese Weise wird dem Bediener auf elektronischem Wege signalisiert, daß ein Wechsel der Bürsten 19 erforderlich ist. Die Änderung der Ansteuerung kann beispielsweise darin bestehen, daß der Antriebsmotor 12 abgeschaltet wird oder nur noch langsam läuft, bzw. im Betrieb brummt. Zusätzlich kann das Detektionssignal s auch zur Erzeugung eines Lichtsignals bzw. eines akustischen Signals weiterverarbeitet werden.The control device 22 changes when the Detection signal s the electrical control of the Drive motor 12 in that the use of Handheld machine tool restricted or even impossible becomes. In this way, the operator is on electronic Paths signals that a change of brushes 19th is required. The change in control can consist, for example, that the drive motor 12 is switched off or only runs slowly, or in Operation is booming. In addition, the detection signal s can also to generate a light signal or an acoustic Signals are processed further.

Ein mechanisches Abschaltorgan für die Bürsten ist bei erfindungsgemäß ausgestatteten Handwerkzeugmaschinen nicht mehr nötig. Die Detektionseinrichtung 26 hat einen kleineren Abstand l von der Rückseite der Bürste 19 und nimmt daher einen erheblich kleineren Anteil an der veränderlichen Gesamtlänge L der Bürsten 19 in Anspruch. Die verfügbare Abriebslänge L-l der Bürsten 19 wird somit verlängert und die Standzeit erhöht.A mechanical shut-off device for the brushes is included Handheld power tools equipped according to the invention are not more needed. The detection device 26 has a smaller one Distance l from the back of the brush 19 and therefore increases a significantly smaller proportion of the variable Total length L of the brushes 19 in claim. The available Abrasion length L-l of the brushes 19 is thus lengthened and the service life increases.

Die Erfindung ist nicht auf das vorstehend beschriebene Ausführungsbeispiel beschränkt. So reicht es aus, eine der Bürsten 19 mit einer Detektionseinrichtung 26 zu versehen, da die Bürsten 19 erfahrungsgemäß ziemlich gleichmäßig abgenutzt werden und normalerweise gleichzeitig ausgetauscht werden müssen. Die Handwerkzeugmaschine kann auch mehr als zwei Bürsten 19 aufweisen.The invention is not based on the above Embodiment limited. So it is enough one of the To provide brushes 19 with a detection device 26, since the brushes 19 experience fairly evenly be worn out and normally replaced at the same time Need to become. The hand machine tool can also do more than have two brushes 19.

Claims (8)

Handwerkzeugmaschine mit einem elektrischen Antriebsmotor (12), der einen Kommutator (18) aufweist, mit dem wenigstens zwei Bürsten (19) in elektrisch leitendem Kontakt stehen, wobei eine Detektionseinrichtung (26) vorgesehen ist, die bei Erreichen einer Mindestlänge (l) zumindest einer der Bürsten (19) ein Detektionssignal (s) erzeugt, dadurch gekennzeichnet, daß die Detektionseinrichtung (26) mit einer Steuereinrichtung (22) für den Antriebsmotor (12) verbunden ist, die bei Auftreten des Detektionssignals (s) eine Änderung der elektrischen Ansteuerung des Antriebsmotors (12) bewirkt.Hand machine tool with an electric drive motor (12), which has a commutator (18) with the at least two brushes (19) are in electrically conductive contact, wherein a detection device (26) is provided which when reaching a minimum length (l) at least one of the Brushes (19) generates a detection signal (s), thereby characterized in that the detection device (26) with a Control device (22) for the drive motor (12) connected is a when the detection signal (s) occurs Change in the electrical control of the drive motor (12) causes. Handwerkzeugmaschine nach Anspruch 1, dadurch gekennzeichnet, daß der Antriebsmotor (12) bei Vorliegen des Detektionssignals (s) von der Steuereinrichtung (22) abschaltbar ist.Hand tool according to claim 1, characterized characterized in that the drive motor (12) in the presence of the Detection signal (s) from the control device (22) can be switched off. Handwerkzeugmaschine nach Anspruch 1, dadurch gekennzeichnet, daß der Antriebsmotor (12) bei Vorliegen des Detektionssignals (s) mit verringerter Leistung ansteuerbar ist.Hand tool according to claim 1, characterized characterized in that the drive motor (12) in the presence of the Detection signal (s) can be controlled with reduced power is. Handwerkzeugmaschine nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß das Detektionssignal (s) zusätzlich zur Erzeugung eines optischen und/oder akustischen Signals dient. Hand machine tool according to one of the preceding Claims, characterized in that the detection signal (s) in addition to generating an optical and / or serves acoustic signal. Handwerkzeugmaschine nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Detektionseinrichtung (26) ein Drahtstück (30) aufweist, das an zumindest einer der Bürsten (19) in einem durch den Abrieb veränderbaren Abstand (L - l) vom dem Kommutator (18) zugewandten Ende angeordnet ist.Hand machine tool according to one of the preceding Claims, characterized in that the Detection device (26) has a piece of wire (30) which on at least one of the brushes (19) in one through the Abrasion variable distance (L - l) from the commutator (18) facing end is arranged. Handwerkzeugmaschine nach Anspruch 5, dadurch gekennzeichnet, daß das Drahtstück (30) durch eine Isolierschicht gegenüber der Bürste (19) isoliert ist.Hand tool according to claim 5, characterized characterized in that the piece of wire (30) by a Insulating layer against the brush (19) is insulated. Handwerkzeugmaschine nach Anspruch 6, dadurch gekennzeichnet, daß das Drahtstück (30) über einen Detektionsleiter (24) mit der Steuereinrichtung (22) verbunden ist und bei abgeriebener Bürste (19) in elektrischen Kontakt mit der Bürste (19) bzw. dem Kommutator (18) gerät.Hand tool according to claim 6, characterized characterized in that the piece of wire (30) over a Detection conductor (24) with the control device (22) is connected and when the brush (19) is rubbed in electrical contact with the brush (19) or the commutator (18) device. Handwerkzeugmaschine nach einem der Ansprüche 5 bis 7, dadurch gekennzeichnet, daß das Drahtstück (30) in das dem Kommutator abgewandten Ende der Bürste (19) integriert ist.Hand tool according to one of claims 5 to 7, characterized in that the piece of wire (30) in the Commutator facing end of the brush (19) is integrated.
EP97121395A 1997-01-31 1997-12-05 Handheld power tool with a detector, which gives a service signal when the carbon brushes reach a minimum length Expired - Lifetime EP0856384B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19703644A DE19703644A1 (en) 1997-01-31 1997-01-31 Hand tool
DE19703644 1997-01-31

Publications (2)

Publication Number Publication Date
EP0856384A1 true EP0856384A1 (en) 1998-08-05
EP0856384B1 EP0856384B1 (en) 2004-11-03

Family

ID=7818944

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97121395A Expired - Lifetime EP0856384B1 (en) 1997-01-31 1997-12-05 Handheld power tool with a detector, which gives a service signal when the carbon brushes reach a minimum length

Country Status (2)

Country Link
EP (1) EP0856384B1 (en)
DE (2) DE19703644A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004003711A1 (en) * 2004-01-24 2005-08-18 Festool Gmbh Power tool, comprising electronic unit positioned parallel to operating button for avoidance of damage
DE102006009529A1 (en) * 2006-02-28 2007-09-06 Gefeg-Neckar Antriebssysteme Gmbh Electrical motor, has mechanical commutation system, consisting motor shaft connecting to rotating commutator and two brushes, and integrated operating electronics contains medium for measuring abrasion grades in commutation system
DE102010031415B4 (en) * 2010-07-15 2016-07-07 Schunk Kohlenstofftechnik Gmbh carbon brush

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0023537A1 (en) * 1979-07-21 1981-02-11 REKOFA Wenzel GmbH & Co KG. Carbon brush with disconnection device
FR2557352A1 (en) * 1983-12-22 1985-06-28 Fein C & E Hand-held electric tool with switching device for right and left rotation.
US4536670A (en) * 1981-12-14 1985-08-20 Morganite Incorporated Electrical brushes with wear sensors
US4723084A (en) * 1986-11-13 1988-02-02 General Electric Company Light conductor brush wear detector assembly
US4739208A (en) * 1986-11-13 1988-04-19 General Electric Company Brush assembly including brush wear detector
DE4137384C1 (en) * 1991-11-14 1993-04-22 Hilti Ag, Schaan, Li Fault warning circuitry for electric power tool - has sensor built into motor to detect wear of carbon@ brushes
DE19649212A1 (en) * 1995-12-27 1997-07-03 Makita Corp Electric motor commutator sliding carbon brush wear/replacement indicator e.g. for electric power tool

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0023537A1 (en) * 1979-07-21 1981-02-11 REKOFA Wenzel GmbH & Co KG. Carbon brush with disconnection device
US4536670A (en) * 1981-12-14 1985-08-20 Morganite Incorporated Electrical brushes with wear sensors
FR2557352A1 (en) * 1983-12-22 1985-06-28 Fein C & E Hand-held electric tool with switching device for right and left rotation.
US4723084A (en) * 1986-11-13 1988-02-02 General Electric Company Light conductor brush wear detector assembly
US4739208A (en) * 1986-11-13 1988-04-19 General Electric Company Brush assembly including brush wear detector
DE4137384C1 (en) * 1991-11-14 1993-04-22 Hilti Ag, Schaan, Li Fault warning circuitry for electric power tool - has sensor built into motor to detect wear of carbon@ brushes
DE19649212A1 (en) * 1995-12-27 1997-07-03 Makita Corp Electric motor commutator sliding carbon brush wear/replacement indicator e.g. for electric power tool

Also Published As

Publication number Publication date
DE59712061D1 (en) 2004-12-09
EP0856384B1 (en) 2004-11-03
DE19703644A1 (en) 1998-08-06

Similar Documents

Publication Publication Date Title
EP0918996A1 (en) Motor with speed of rotation detected by a hall sensor
DE2203839A1 (en) CONTROL UNIT FOR SWITCHING ON AND OFF A POWERED ELECTRICAL DEVICE
EP2438833A1 (en) Drive unit for mobile pieces of furniture
EP1554086B1 (en) Power tool
EP0856384B1 (en) Handheld power tool with a detector, which gives a service signal when the carbon brushes reach a minimum length
DE102010031415B4 (en) carbon brush
DE19605202C1 (en) Power tool with switchover device for clockwise / anti-clockwise rotation
DE3340799A1 (en) Electric tool
DE2147790B2 (en) Switching device for reversing the direction of rotation of a commutator motor
WO2000045474A1 (en) Carbon brush
DE4141307A1 (en) BRUSH GUIDE ARRANGEMENT FOR ELECTRICAL MACHINES
DE19705833A1 (en) Brush holding arrangement
DE3604583A1 (en) MINIATURE MOTOR
DE1959099C3 (en)
DE10001459B4 (en) Power tool with reversing switch
EP0806818B1 (en) Brush holder
EP2553794A2 (en) Handheld electric tool
EP2067239A1 (en) Electrical drive unit
DE102010041507A1 (en) Hand-guided electric power tool i.e. battery screw-driller, has commutation device with commutator that is in sliding contact with brushes, where one of brushes is arranged in shielding elements for shielding electromagnetic-interference
EP1843452A1 (en) Brush holder device
DE19853506B4 (en) Acoustic signal transmitter
EP0658393A1 (en) Welding device
DE19742091A1 (en) Holder for slide contact part for electrical machine
DE2949647A1 (en) Teeth polishing appts. for calcification removal - has rotary polishing bit fitted to head of motor housing
DE4021462A1 (en) THREAD STORAGE WITH ELECTRICAL CONNECTION IN THE STORAGE BODY

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE GB IT LI

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990205

AKX Designation fees paid

Free format text: CH DE GB IT LI

RBV Designated contracting states (corrected)

Designated state(s): CH DE GB IT LI

17Q First examination report despatched

Effective date: 20030226

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE GB IT LI

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20041103

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: NV

Representative=s name: SCINTILLA AG, DIREKTION

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 59712061

Country of ref document: DE

Date of ref document: 20041209

Kind code of ref document: P

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20050228

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050804

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20081222

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20100218

Year of fee payment: 13

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091231

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20091231

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20101221

Year of fee payment: 14

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 59712061

Country of ref document: DE

Effective date: 20110701

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20110701

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20111205

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20111205