DE19842343A1 - Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft - Google Patents

Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft

Info

Publication number
DE19842343A1
DE19842343A1 DE1998142343 DE19842343A DE19842343A1 DE 19842343 A1 DE19842343 A1 DE 19842343A1 DE 1998142343 DE1998142343 DE 1998142343 DE 19842343 A DE19842343 A DE 19842343A DE 19842343 A1 DE19842343 A1 DE 19842343A1
Authority
DE
Germany
Prior art keywords
friction clutch
clutch
fluid friction
base
storage chamber
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.)
Withdrawn
Application number
DE1998142343
Other languages
German (de)
Inventor
Claus Augenstein
Ralf Maus
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.)
Mahle Behr GmbH and Co KG
Original Assignee
Behr GmbH and Co KG
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 Behr GmbH and Co KG filed Critical Behr GmbH and Co KG
Priority to DE1998142343 priority Critical patent/DE19842343A1/en
Publication of DE19842343A1 publication Critical patent/DE19842343A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D28/00Electrically-actuated clutches
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D27/00Magnetically- or electrically- actuated clutches; Control or electric circuits therefor
    • F16D27/02Magnetically- or electrically- actuated clutches; Control or electric circuits therefor with electromagnets incorporated in the clutch, i.e. with collecting rings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16DCOUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D35/00Fluid clutches in which the clutching is predominantly obtained by fluid adhesion
    • F16D35/02Fluid clutches in which the clutching is predominantly obtained by fluid adhesion with rotary working chambers and rotary reservoirs, e.g. in one coupling part
    • F16D35/021Fluid clutches in which the clutching is predominantly obtained by fluid adhesion with rotary working chambers and rotary reservoirs, e.g. in one coupling part actuated by valves
    • F16D35/024Fluid clutches in which the clutching is predominantly obtained by fluid adhesion with rotary working chambers and rotary reservoirs, e.g. in one coupling part actuated by valves the valve being actuated electrically, e.g. by an electromagnet

Abstract

A fluid friction clutch with a storage chamber (34) in the drive disk (30) and an electromagnetic control (45, 46) of the oil return is described. A bypass duct (44) branches off from the return duct (42) and is controlled via a valve lever (45). A stationary ring magnet (46), which actuates the valve lever (45), is arranged outside the coupling. This reverse control enables the clutch to be switched on quickly. The clutch is preferably used to drive fans for cooling internal combustion engines for motor vehicles.

Description

The invention relates to a fluid friction clutch according to the Preamble of claim 1. Such a coupling corresponds to the earlier application of the applicant with the file number 197 41 073.1.

In this coupling according to the prior art, the return of the vis kosen medium controlled by a solenoid valve, which is in one to additional, stationary with respect to the coupling coupling part be finds. This so-called valve carrier, which also opens the return channel takes, represents a considerable constructive for such a coupling This represents additional expenditure, which also ver with correspondingly higher manufacturing costs is bound. Such constructions can be used for commercial vehicle couplings, but not for car clutches where simpler and cheaper more construction methods are required.

The object of the invention is therefore the fluid friction clutch type mentioned to improve in that at the same Re the design effort and the manufacturing costs can be reduced.

This object is achieved by the characterizing features of the patent Proverb 1 solved, the solution being that of the return channel a bypass duct branches off in the main body of the coupling, which goes directly into the  Working area of the clutch leads and is controlled via a valve. Thereby is achieved by the return flow of the viscous medium if necessary a partial flow is branched off by opening the bypass duct, which flows directly into the working chamber flows and there for a quick connection of the Clutch leads. At the same time, the size of the coupling is compared the prior art significantly reduced because of the additional valve support not applicable.

In an advantageous development of the invention is according to claims 2-4 provided that the valve control takes place via a ring magnet, the is arranged outside the clutch and is mounted on the drive shaft. This results in a simple construction and yet the advantages of one electromagnetic return control.

In a further embodiment of the invention are according to claims 5-7 slip rings on the outside of the clutch housing and on the inside thereof Pole shoes arranged - this creates a concentrated magnetic flux achieved from the ring magnet to the valve lever, so that a smaller magnet with less power.

According to a further embodiment of the invention according to claim 8 a partition plate to limit the pantry provided what enables a light construction.

Finally, according to a development of the invention according to claim 9 so-called siphon inside the pantry in the base body arranges out the circular channel extending approximately 180 degrees in circumference forms and the inlet bore is upstream. Such a ring channel is already in the earlier patent application with the file number 198 10 905.9 described by the applicant, but there as a return channel.

Embodiments of the invention are shown in the drawing and are described in more detail below. Show it

Fig. 1 shows a section through the coupling in the plane AA,

Fig. 2 shows a section through the coupling in the plane BB,

Fig. 3 is a view of the so-called base body with a valve lever,

Fig. 4 shows a section through the coupling in another embodiment and

Fig. 5 is a view of the base body with pole pieces.

In Figs. 1 and 2, a fluid friction clutch is in 2 various which sectional planes shown, in Fig. 1 in the sectional plane A-A of FIG. 3 and in FIG. 2 in the section plane BB, also accelerator as Fig. 3 . The fluid friction clutch according to Fig. 1 is driven by a drive shaft 1, a drive pulley 2 is fixed rotatably on the end thereof for. B. by shrinking. On the drive shaft 1 , a clutch housing 3 , consisting of a so-called base body 3 a and a cover 3 b, is rotatably supported by a ball bearing 4 . On the clutch housing, ie the base body 3 a, a flange 5 is attached which carries an axial fan, not shown. The clutch is driven by an internal combustion engine (not shown) of a motor vehicle and the axial fan (also not shown) is used to convey cooling air through a heat exchanger (not shown). The drive disc 2 forms with the clutch housing 3 a, 3 b, a working chamber 6 , the gap between a profile 6 a of the drive disc and a corresponding profile 6 b of the cover 3 b forms. This column or the working chamber 6 are covered with a viscous medium, e.g. B. silicone oil filled. The drive pulley 2 has a storage chamber 7 which is delimited on the one hand by the drive pulley 2 itself and on the other hand by a partition 8 . In the drive pulley 2 , an inlet channel 9 is arranged, which is designed as a calibrated bore. The return channel is connected to a ring-shaped channel 10 , which has the function of a siphon and extends approximately over 180 degrees of the circumference and is at its other end 10 a with the storage chamber 7 in connection. Radially outside of the drive pulley 2 , but within the working space 6 there is a jam body 11 , which is adjacent to a return bore 12 which is connected to the storage chamber 7 via a return channel 13 , 14 . From the return channel 13 , which extends in the radial direction in the main body 3 a, branches off in the axial direction from a bypass channel 15 which opens into the working chamber 6 and is closed or opened by a valve lever 16 , who can. Approximately at the radial level of the valve lever 16 , ie located somewhat radially within, a ring magnet 17 is arranged, which is mounted in a stationary manner in a manner not shown. In the base body 3 a are coaxial to the ring magnet 17 in its diameter range slip rings 18 , 19 are inserted, which are in sliding contact with the ring magnet on the one hand and on the other hand extend to the wall of the return channel 13 , but without breaking this wall.

FIG. 2 shows the same clutch as in FIG. 1, but in the sectional plane BB, ie in a plane outside the return channel 13 , but in the area of the valve lever 16 , which is shown in its top view in FIG. 3. In the diameter range of the slip rings 18 , 19 , axially aligned pole pieces 20 and 21 are inserted into the base body 3 a, material webs 3 c and 3 d being left between the end faces of the slip rings 18 , 19 on the one hand and the pole pieces 20 , 21 on the other hand, so that the wall of the base body 3 is not broken and thus there is no leakage ent. The pole pieces 20 , 21 extend with their end face directly into the working chamber 6 , where an anchor plate 16 a of the valve lever 16 is arranged.

In Fig. 3, the entire valve lever is shown in a plan view sixteenth He is with one end on the base body 3 a by means of two screws 22 , 23 BEFE Stigt. The valve lever 16 is designed as a leaf spring and closes the bypass bore 15 by means of a spherical shape 16 b when the armature plate 16 a is attracted by the ring magnet 17 . In the relieved state, the valve lever 16 releases the bypass bore 15 .

Fig. 4 shows a further embodiment of the liquid friction clutch, again shown in section. This clutch shows a slightly modified drive pulley 30 with an axially extending inlet channel 31 , which is preceded by an annular channel-shaped siphon 32 . The drive disk 30 forms a storage chamber 34 with a partition 33 . On a drive shaft 35 , a base 37 is mounted by means of a first ball bearing 36 , which is completed with a clutch cover 38 to the clutch housing. This clutch housing forms with the drive disk 30 , which in turn is profiled, a working space 39 in which a bluff body 40 is located radially outside. This is followed by a return bore 41 , which is connected to a return channel 42 via an overflow 43 with the storage chamber 34 . From the return duct 42 branches off a bypass duct 44 which opens into the working chamber 40 and can be closed by a valve lever 45 . On the drive shaft 35 , a ring magnet 46 is mounted in a stationary manner by means of a torque support 48 a and connected to a power cable 48 , directly on the rear of the clutch, ie adjacent to the base body 37 , via a second ball bearing 47 . In the base body 37 , slip rings 49 , 50 are fastened in the region of the diameter of the ring magnet 46 , which form an air gap of approximately 0.3 mm with the ring magnet 46 . On the inside of the base body 47 are - analog to the embodiment of FIGS. 1 and 2 - pole shoes are arranged, again in such a way that the wall of the basic body 37 is not broken.

Fig. 5 shows a top view of the base body 37 gem. Fig. 4. On the center line m the bypass bore 44 and on the other hand the return bores 41 and 43 are arranged. Pole shoes 51 , 52 , 53 and 54 are arranged on both sides of the center line, approximately in the shape of a horseshoe and concentrically to one another, which are embedded in the base body 37 - analogously to the exemplary embodiment according to FIGS .

. The coupling of Figures 1-3 operates as follows: a viscous medium, such. B. silicone oil, circulates between the storage chamber 7 and the Ar beitskammer 8 and causes depending on the degree of filling of the working chamber the connection or disconnection of the clutch. When the drive shaft rotates, an oil ring forms in the storage chamber 7 , and under the action of the centrifugal force, oil flows through the siphon 10 and the calibrated inlet bore 9 into the working space 6 , which is thus filled. The inflow of oil is therefore continuous and is determined by the size of the inlet bore 9 - in addition to other parameters such as the drive speed and the viscosity of the oil. The oil is pumped out of the working space 6 via the bluff body 4 , specifically via the bores 12 , 13 and 14 , ie back into the storage space 7 . This is the oil circuit when the valve 15/16, that is, the bypass hole is closed 15th Should be based on certain parameters, e.g. B. The coolant temperature more oil into the working chamber reach, so the valve / open 15 16 so that a partial flow is branched off from the return fluid flowing through the channel 13 oil stream passes directly into the working chamber 6 and thus the for rapid filling Working column ensures. The clutch then switches on relatively quickly. The valve lever 16 is actuated via the ring magnet 17 , the magnetic flux of which is increased up to the anchor plate 16 a of the valve lever via the slip rings 18 , 19 and the pole shoes 20 , 21 . When current is applied to the ring magnet 17 , the magnet pulls the valve lever 16 and closes the bypass bore 15 . When the power supply is interrupted, the valve opens due to the elasticity of the valve lever 16 .

The clutch according to the embodiment of FIGS. 4 and 5 works on the same principle as described above. With regard to the supply of the viscous medium from the storage chamber into the working chamber, there are different characteristics insofar as the inlet bore 9 in the first embodiment is radial and the inlet bore 31 in the second embodiment is axial.

Claims (10)

1. Liquid friction clutch with a drive shaft and a drive shaft attached to it, in which a storage chamber is arranged, with a rotatably arranged on the drive shaft housing, consisting of base body and cover, the drive pulley with the housing forming a working column Ar working chamber, which is connected to the storage chamber on the one hand via an inlet channel and on the other hand via a return channel, and in that a viscous medium circulates between the storage chamber and working chamber, the return flow of which is controlled by an electromagnetic valve, characterized in that between the return channel ( 13 , 42 ) and a working chamber ( 6 , 39 ) a bypass channel ( 15 , 44 ) is arranged, which can be controlled via the valve ( 16 , 45 ).
2. Fluid friction clutch according to claim 1, characterized in that the bypass channel ( 15 , 44 ) is designed as an axially in the base body ( 3 a, 37 ) extending bore, the working chamber ( 6 , 39 ) facing opening through a valve lever ( 16 , 45 ) can be closed.
3. A fluid friction clutch according to claim 2, characterized in that the valve lever ( 16 , 45 ) can be controlled via a magnet ( 17 , 46 ) which is arranged outside the clutch.
4. Fluid friction clutch according to claim 3, characterized in that the magnet is designed as a ring magnet ( 17 , 46 ) and on the back of the clutch on the drive shaft ( 1 , 35 ) is gela Gert.
5. Fluid friction clutch according to claim 4, characterized in that between the ring magnet ( 17 , 46 ) and clutch housing slip rings ( 18 , 19 ; 49 , 50 ) are arranged coaxially and are attached to the outside of the base body ( 3 a, 37 ) of the clutch .
6. Fluid friction clutch according to claim 5, characterized in that coaxial to the slip rings pole pieces ( 20 , 21 ; 51 , 52 , 53 , 54 ) on the inside of the base body ( 3 a, 37 ) are attached.
7. Fluid friction clutch according to claim 6, characterized in that slip rings and pole shoes are used axially in alignment with the base body and that between their end faces each Weil webs ( 3 c, 3 d) of the base body ( 3 a) are left.
8. Fluid friction clutch according to one of claims 2-7, characterized in that the storage chamber ( 7 , 34 ) in the drive disc ( 2 , 30 ) to the side of the housing cover ( 3 b, 38 ) through a partition ( 8 , 33 ) is limited.
9. Fluid friction clutch according to one of claims 1-8, characterized in that the inlet channel ( 9 , 31 ) is a siphon ( 10 , 32 ) in the form of an annular channel in the drive disc ( 2 , 30 ) upstream.
10. Fluid friction clutch according to one of claims 1-9, characterized in that the inlet channel runs radially ( 9 ) or axially ( 31 ) in the drive disk ( 2 , 30 ) and has a calibrated drilling.
DE1998142343 1998-09-16 1998-09-16 Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft Withdrawn DE19842343A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE1998142343 DE19842343A1 (en) 1998-09-16 1998-09-16 Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE1998142343 DE19842343A1 (en) 1998-09-16 1998-09-16 Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft

Publications (1)

Publication Number Publication Date
DE19842343A1 true DE19842343A1 (en) 2000-03-23

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Family Applications (1)

Application Number Title Priority Date Filing Date
DE1998142343 Withdrawn DE19842343A1 (en) 1998-09-16 1998-09-16 Liquid frictional coupling with drive shaft and driving discs fixed on it in which storage chamber is arranged with housing arranged rotationally on shaft

Country Status (1)

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DE (1) DE19842343A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10157822A1 (en) * 2001-11-24 2003-06-05 Behr Gmbh & Co Electromagnetically controlled fluid friction clutch
EP1256738A3 (en) * 2001-05-11 2004-02-25 Horton Sachs GmbH & Co. KG Viscous coupling
FR2846062A1 (en) * 2002-10-22 2004-04-23 Usui Kokusai Sangyo Kk Device for coupling fan to external control comprises valve opening and closing oil accumulation reservoir controlled by electromagnet and magnetic element in sealed casing enables magnetic flux to be transmitted to valve
JP2009523217A (en) * 2005-07-29 2009-06-18 ホートン, インコーポレイテッド Viscous clutch with improved flux circuit
US8887888B2 (en) 2009-11-17 2014-11-18 Horton, Inc. Integrated viscous clutch
JP2016510865A (en) * 2013-03-14 2016-04-11 ホートン, インコーポレイテッド Viscous clutch with minimum output speed
US10385932B2 (en) 2013-03-14 2019-08-20 Horton, Inc. Viscous clutch and associated flux circuit configuration

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0055122A1 (en) * 1980-12-22 1982-06-30 Household Manufacturing, Inc. Fluid shear coupling apparatus
DE3324982A1 (en) * 1982-07-12 1984-01-19 Aisin Seiki Fluid coupling approaching temperature
DE2414017C2 (en) * 1973-05-24 1987-01-22 Dynair Ltd., Nailsworth, Gloucestershire, Gb
DE3739564A1 (en) * 1986-11-21 1988-06-01 Usui Kokusai Sangyo Kk Temperature sensitive liquid type fan coupling
EP0279271A1 (en) * 1987-02-19 1988-08-24 Behr GmbH & Co. Fluid friction coupling
DE3843709A1 (en) * 1987-12-28 1989-07-06 Usui Kokusai Sangyo Kk Temperature-actuated fluid driving coupling
DE3823871A1 (en) * 1988-07-14 1990-01-18 Sueddeutsche Kuehler Behr Liquid friction clutch, in particular for driving a fan for cooling motor vehicle engines
DE19646281A1 (en) * 1995-11-10 1997-05-15 Usui Kokusai Sangyo Kk Hydraulic friction clutch in motor vehicle engines

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2414017C2 (en) * 1973-05-24 1987-01-22 Dynair Ltd., Nailsworth, Gloucestershire, Gb
EP0055122A1 (en) * 1980-12-22 1982-06-30 Household Manufacturing, Inc. Fluid shear coupling apparatus
DE3324982A1 (en) * 1982-07-12 1984-01-19 Aisin Seiki Fluid coupling approaching temperature
DE3739564A1 (en) * 1986-11-21 1988-06-01 Usui Kokusai Sangyo Kk Temperature sensitive liquid type fan coupling
EP0279271A1 (en) * 1987-02-19 1988-08-24 Behr GmbH & Co. Fluid friction coupling
DE3843709A1 (en) * 1987-12-28 1989-07-06 Usui Kokusai Sangyo Kk Temperature-actuated fluid driving coupling
DE3823871A1 (en) * 1988-07-14 1990-01-18 Sueddeutsche Kuehler Behr Liquid friction clutch, in particular for driving a fan for cooling motor vehicle engines
DE19646281A1 (en) * 1995-11-10 1997-05-15 Usui Kokusai Sangyo Kk Hydraulic friction clutch in motor vehicle engines

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1256738A3 (en) * 2001-05-11 2004-02-25 Horton Sachs GmbH & Co. KG Viscous coupling
US7191883B2 (en) 2001-11-24 2007-03-20 Behr Gmbh & Co. Kg Electromagnetically controlled fluid friction coupling
DE10157822A1 (en) * 2001-11-24 2003-06-05 Behr Gmbh & Co Electromagnetically controlled fluid friction clutch
FR2846062A1 (en) * 2002-10-22 2004-04-23 Usui Kokusai Sangyo Kk Device for coupling fan to external control comprises valve opening and closing oil accumulation reservoir controlled by electromagnet and magnetic element in sealed casing enables magnetic flux to be transmitted to valve
US8100241B2 (en) 2005-07-29 2012-01-24 Horton, Inc. Viscous clutch with eddy current reduction
JP2009523217A (en) * 2005-07-29 2009-06-18 ホートン, インコーポレイテッド Viscous clutch with improved flux circuit
US7854307B2 (en) 2005-07-29 2010-12-21 Horton, Inc. Electromagnetically actuated viscous clutch
US7938240B2 (en) 2005-07-29 2011-05-10 Horton, Inc. Viscous clutch
US7946400B2 (en) 2005-07-29 2011-05-24 Horton, Inc. Viscous clutch
US8887888B2 (en) 2009-11-17 2014-11-18 Horton, Inc. Integrated viscous clutch
JP2016510865A (en) * 2013-03-14 2016-04-11 ホートン, インコーポレイテッド Viscous clutch with minimum output speed
US9506507B2 (en) 2013-03-14 2016-11-29 Horton, Inc. Multi-speed viscous clutch
CN105190072B (en) * 2013-03-14 2017-03-15 霍顿公司 Viscous clutch and the method for operating viscous clutch
US10385932B2 (en) 2013-03-14 2019-08-20 Horton, Inc. Viscous clutch and associated flux circuit configuration

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