US3838757A - Internal shoe-drum brakes - Google Patents

Internal shoe-drum brakes Download PDF

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Publication number
US3838757A
US3838757A US00334612A US33461273A US3838757A US 3838757 A US3838757 A US 3838757A US 00334612 A US00334612 A US 00334612A US 33461273 A US33461273 A US 33461273A US 3838757 A US3838757 A US 3838757A
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United States
Prior art keywords
shoe
screw
spindle
engagement
brake
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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.)
Expired - Lifetime
Application number
US00334612A
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English (en)
Inventor
G Farr
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Girling Ltd
Original Assignee
Girling Ltd
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Filing date
Publication date
Application filed by Girling Ltd filed Critical Girling Ltd
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Publication of US3838757A publication Critical patent/US3838757A/en
Anticipated expiration legal-status Critical
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D65/00—Parts or details
    • F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
    • F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
    • F16D65/22—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for pressing members apart, e.g. for drum brakes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D65/00—Parts or details
    • F16D65/38—Slack adjusters
    • F16D65/40—Slack adjusters mechanical
    • F16D65/52—Slack adjusters mechanical self-acting in one direction for adjusting excessive play
    • F16D65/56—Slack adjusters mechanical self-acting in one direction for adjusting excessive play with screw-thread and nut
    • F16D65/561—Slack adjusters mechanical self-acting in one direction for adjusting excessive play with screw-thread and nut for mounting within the confines of a drum brake

Definitions

  • ABSTRACT [30] Foreign Application Priority Data Marv 3, 1972 Great Britain 9920/72 I n int rnal hoe-drum brake in which an actuator Mar. 9, l972 Great Britain 10952/72 for eparating the shoes is located between the shoes at one end, the other ends of the shoes abut on mem- [52] [1.3. Cl 188/795 P, 188/196 D berg slidable in a stationary body and separated by an [51] Int. Cl. F16d 65/56 i t rm di te om onent which includes a stop limit- Field of Search 188/795 GC, ing movement of one member towards the other and 196 D may include means for automatically adjusting the separation of the members.
  • an actuator for separating the shoes is located between the shoes at one end, and between the other ends of the shoes there is located an abutment unit comprising a body fixed to the stationary back plate of the brake, a first normally non-rotatable member slidable in the body for co-operation with the end of one shoe, a second normally non-rotatable member slidable in the body for co-operation with the end of the other shoe and an intermediate component extending between the' members and including a stop or stops adapted to engage with a part of the body to limit movement of one member towards the other.
  • first and second members comprise pistons or plungers axially slidable in aligned bores in the body
  • the intermediate component comprises a spindle which is in screw-threaded engagement with one or both members and is preferably rotatable by automatic adjusting means to adjust the effective length of the assembly formed by the two members and the spindle.
  • One of the members is preferably arranged to be axially slidable relative to the spindle and may be actuated by fluid pressure to produce a two-leading-shoe operation of the brake, usually in the normal forward direction of rotation of the brake drum, the brake conveniently being arranged to produce duo-servo action in the opposite direction of rotation of the drum.
  • both members may be actuated by fluid pressure which ensures that in duo-servo operation of the brake in said opposite direction of rotation of the drum the secondary shoe is always positively actuated even if fading of the primary shoe lining reduces the input force to the assembly to an unacceptable value.
  • the intermediate component comprises a two-part spindle of which one part is in screw-threaded engagement with one member and the other part is in direct or indirect screw-threaded engagement with the other member, the two parts being alternatively rotatable by automatic adjusting means to adjust independently the position of each member in the body to compensate for wear of the co-operating shoe.
  • FIG. 1 is a front elevation of a brake
  • FIG. 2 is a vertical section on the line 22 of FIG.
  • FIG. 3 is a horizontal section on the line 3--3 of FIG.
  • FIG. 4 is a section similar to FIG. 3 of a modified form of abutment unit
  • FIG. 5 is another section similar to FIG. 3 of another modified form of abutment unit
  • FIG. 6 is another section similar to FIG. 3 showing a still further form of abutment unit.
  • two opposed arcuate brake shoes 1, 2 are mounted on a stationary back plate 3 and carry friction linings 4 for engagement with a rotatable brake drum (not shown).
  • the shoes are separated at their upper ends to apply the brake by a wedge 5 actuated by a fluid-pressure motor indicated at 6.
  • an abutment unit 7 incorporating means for separating the shoes and for adjusting them automatically to compensate for wear of the linings.
  • the abutment unit as shown in section in FIG. 3, is an open-ended fluid pressure cylinder 8 mounted on the back plate 3.
  • Pistons 9, 10 work in opposite ends of the cylinder.
  • the piston 9 has an axial recess in its outer end in which is rotatably mounted a spigot 11 on the inner end of a tappet 12 adapted to engage the shoe 1.
  • a tappet 13 for engagement with the shoe 2 is integral with the piston 10.
  • the pistons are provided with the usual seals 14.
  • a spindle 15 extends axially within the cylinder through an annular shoulder or partition 16.
  • One end of the spindle is in screw-threaded engagement with a blind axial bore in the inner end of the piston 9 and the other end is in screw-threaded engagement with a nut 17 which can slide axially but is keyed against rotation in a counterbored part of a blind axial bore in the inner end of the piston 10.
  • the sxrewthreads on opposite ends of the spindle are right and left handed respectively so that rotation of the spindle moves the pistons axially in opposite direction.
  • the inner end of the piston 10 is normally spaced a short distance from the adjacent end of the shoulder 16, the gap being indicated at 18.
  • the spindle has a collar 19 of substantial diameter adapted to bear on the opposite end of the shoulder 16.
  • An intermediate portion of the spindle is formed with a screw-thread 20 of steep pitch, and working on this portion is an internally threaded drive ring 21 of which the outer surface is coned for co-operation with an interal frusto-conical face 22 on the shoulder 16.
  • the ring is urged into clutching engagement with the face 22 by a coiled spring 23, and a concentric spring 24 is arranged between the collar 19 and an internal annular step 25 in the shoulder 16.
  • the desired minimum shoe clearance in the off position of the brake is allowed for by play in the various screw-threaded connections.
  • this clearance is exceeded owing to wear of the shoe-linings movement of the piston to the left (in FIG. 3) takes up the clearances and moves the drive ring 21 to the left to reduce the clutching engagement with the face 22 so that it can rotate as the spindle moves to the left through it.
  • the spring 23 overcomes the friction in the thread 20 on the spindle which would otherwise tend to carry the drive ring to the left with the spindle.
  • the spring 24 prevents the spindle from being rotated as the ring rotates due to torque generated by the friction in the thread.
  • the ratio of the pitch of the thread on the spindle to those of the threaded engagements of the spindle with the pistons is such that only a small part say one thirtieth of the wear is taken up on each adjustment so that the adjuster is of the incremental type.
  • the nut 17 can be fixed in the piston 10 which does not need to slide independently of the spindle.
  • the brake acts as a leading-trailing shoe brake in the forward direction and as a duo-servo brake in the reverse direction.
  • teeth 26 are formed on the outer end of the piston 9 to allow it to be rotated manually with a suitable tool to contract the adjuster and to enable the brake drum to be removed in the event of grooving of the drum, for example, or to release a jammed adjuster. Rotation of the piston without affecting the shoe 1 is permitted by the rotatable spigot connection between the piston and the tappet 12.
  • One is to reduce the input to the shoe 2 relative to the shoe 1, either by applying a higher actuating force to the upper ends of the shoes than to their lower ends or by using a stronger return spring at the bottom than at the top.
  • the brake will act as a two-leading shoe brake in both directions of rotation of the drum.
  • the other end of the spindle is of hexagonal or other non-circular cross-section and is in sliding engagement with a bore in a sleeve 38 of which the outer surface is in screw-threaded engagement with a blind axial bore in the piston 31.
  • a drive ring 39 is in screw-threaded engagement with a thread 40 of steep pitch on the spindle and the peripheral surface of the ring is coned for engagement with a frusto-conical face 41 on the shoulder 37 towards which it is urged by a spring 42.
  • Teeth 43 are formed on the outer ends of both pistons for adjusting them manually and independently by means of a suitable tool.
  • the body 50 which is adapted to be secured to the back plate of the brake, is formed with aligned bores 51, 52 in which pistons 53 and 54 respectively work.
  • the pistons carry at their outer ends tappets 55 and 56 for engagement with the ends of the brake shoes.
  • a stud 57 having a head 58 at its inner end is in irreversible screw-threaded engagement with a blind bore 59 in the piston 53, and a similar stud 60 having a head 61 at its inner end is in irreversible screw-threaded engagement with a blind bore 62 in the piston 54.
  • An axial extension 63 of the stud 57 is a sliding fit in a blind bore 64 in the stud 60, and a spring 65 located between the extension and the end of the bore maintains an axial load on the screw-threaded engagements between the studs and the pistons.
  • An internal annular abutment 66 in the body between the bores 51 and 52 has opposed inclined faces 67, 68 co-operating with complementary inclined faces on the heads of the studs, the abutment providing stops for the inward movement of both pistons.
  • a reversible screw-thread 69 of steep pitch is formed on the extension 63, and a double-coned non-handed drive ring 70 is in engagement with this thread.
  • the ring is urged by a spring 71 into clutching engagement with a coned surface 72 in a recess in the inner end of the stud 60.
  • the shoe 2 forces the stud 60 against the face 68 on the abutment.
  • the piston 53 lifts the stud 57 away from the face 67 and if the wear of the shoe 1 is excessive the extension 63 is pulled through the drive ring 70, and the the spring 71 causes the drive ring to rotate around the extension.
  • the extension 63 can be rigidly connected to the stud 57 but it has been found sufficient to provide the extension with a head 73 in clutching engagement with the inner end of the stud.
  • If necessary separate means can be used to provide a greater shoe tip effort at the actuated ends of the shoes than at the abutment unit, as for example by using hydraulic pistons of greater diameter in the actuator and/or by using shoe return springs of greater strength.
  • An internal shoe-drumbrake in which arcuate shoes are mounted on a stationary back plate and an actuator for separating the shoes is located between the shoes at one end and an abutment unit is located between the other ends of the shoes, said abutment unit comprising a body fixed to the stationary back plate, a flrst normally non-rotatable member slidable in the body for co-operation with one shoe, a second normally non-rotatable member axially slidable in the body for co-operation with the end of the other shoe, and an intermediate component extending between the members and including stops adapted to engage with a part of the body and to limit movement of one member towards the other.
  • said automatic adjustment means comprises a drive ring which has a reversible screw-threaded engagement with an intermediate part of the spindle and a springloaded coned clutching engagement with a part of the body, excess axial movement of a member in the application of the brake reducing the clutching engagement of the drive ring with the body and allowing said ring to be rotated by axial movement of the spindle.
  • said intermediate component comprises an assembly including a first headed stud in screw-threaded engagement with a blind bore in one member, a second headed stud in screw-threaded engagement with a blind bore in the other member, an axial extension of the first extension of the first headed stud and a drive ring working on said thread and in spring-loaded clutching engagement with the secons stud, the clutching engagement being freed by excess axial movement of the second member in the application of the brake whereby the ring is rotated by axial movement of the extension through it.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Braking Arrangements (AREA)
US00334612A 1972-03-03 1973-02-22 Internal shoe-drum brakes Expired - Lifetime US3838757A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB992072A GB1418681A (en) 1972-03-03 1972-03-03 Internal shoedrum brakes
GB1095272 1972-03-09

Publications (1)

Publication Number Publication Date
US3838757A true US3838757A (en) 1974-10-01

Family

ID=26243261

Family Applications (1)

Application Number Title Priority Date Filing Date
US00334612A Expired - Lifetime US3838757A (en) 1972-03-03 1973-02-22 Internal shoe-drum brakes

Country Status (7)

Country Link
US (1) US3838757A (zh)
JP (1) JPS48100566A (zh)
AU (1) AU5263973A (zh)
DE (1) DE2310608C2 (zh)
FR (1) FR2175439A5 (zh)
GB (1) GB1418681A (zh)
IT (1) IT979719B (zh)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3952845A (en) * 1974-02-16 1976-04-27 Girling Limited Brake adjusters
US4056175A (en) * 1975-09-30 1977-11-01 Girling Limited Slack adjusters for the shoes of vehicle shoe drum brakes of the duo servo type
US4085830A (en) * 1975-10-03 1978-04-25 Girling Limited Automatic slack adjusters for vehicle brakes
US4369863A (en) * 1979-08-31 1983-01-25 Lucas Industries Limited Internal shoe drum brakes for vehicles
US4535875A (en) * 1982-03-09 1985-08-20 Lucas Industries, Public Limited Company Actuator for an internal shoe drum brake
US4537293A (en) * 1980-12-09 1985-08-27 Automotive Products Plc Hydraulic cylinder assemblies
US4742897A (en) * 1985-11-29 1988-05-10 Akebono Brake Industry Company, Ltd. Wheel cylinder with self-contained auto-adjuster
US4792021A (en) * 1982-03-26 1988-12-20 Nissin Kogyo Kabushiki Kaisha Self-compensating device for a drum brake
US4887697A (en) * 1986-09-26 1989-12-19 Lucas Industries Public Limited Company Brake actuator
US4986394A (en) * 1986-06-26 1991-01-22 Lucas Industries Brake actuator
EP1013959A1 (de) * 1998-12-17 2000-06-28 Volkswagen Aktiengesellschaft Hydraulisch betriebener Radbremszylinder zur Betätigung der Bremsbacken einer Trommelbremse
US6325181B1 (en) 1999-07-30 2001-12-04 Kelsey-Hayes Company Piston assembly for use in a wheel cylinder of a drum brake assembly
EP1160475A2 (en) * 2000-06-01 2001-12-05 Nisshinbo Industries, Inc. Dual mode drum brake device
US6454057B2 (en) * 2000-08-01 2002-09-24 Nisshinbo Industries Inc. Brake cylinder
US20100044165A1 (en) * 2006-07-31 2010-02-25 Vasil Argirovski Compact Disc-Brake Unit For Vehicles On Rails
US11300170B2 (en) * 2017-10-12 2022-04-12 Continental Teves Ag & Co. Ohg Spreader unit for a drum brake, comprising wear travel adjustment, and the drum brake

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8316390D0 (en) * 1983-06-16 1983-07-20 Lucas Ind Plc Automatic adjuster
JPS6019831U (ja) * 1983-07-18 1985-02-12 日清紡績株式会社 ブレ−キ用シリンダ装置
US5246091A (en) * 1992-06-01 1993-09-21 General Motors Corporation Drum brake wheel cylinder with internal adjuster
FR2778712A1 (fr) 1998-05-14 1999-11-19 Bosch Syst Freinage Dispositif de rattrapage d'usure notamment pour un frein de vehicule

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3200909A (en) * 1963-07-09 1965-08-17 Kelsey Hayes Co Automatic brake adjusting mechanism
US3532193A (en) * 1967-04-13 1970-10-06 Alfed Teves Gmbh Duo-duplex internal expansion brake
US3744595A (en) * 1970-08-14 1973-07-10 Girling Ltd Vehicle drum brakes

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2173582A (en) * 1932-07-28 1939-09-19 Bendix Aviat Corp Brake
US2130875A (en) * 1936-02-10 1938-09-20 Howard D Colman Self-adjusting hydraulic brake
GB620995A (en) * 1947-02-07 1949-04-01 Fodens Ltd Improvements relating to vehicle brake adjusting mechanism
DE1865018U (de) * 1962-11-05 1963-01-03 Mueller Hermann E Fa Servobremse.
JPS4324200Y1 (zh) * 1964-09-12 1968-10-12
DE1575825B1 (de) * 1967-02-28 1970-04-30 Perrot Bremse Gmbh Deutsche Selbsttaetige Nachstellvorrichtung fuer Bremsbacken von Reibungsbremsen

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3200909A (en) * 1963-07-09 1965-08-17 Kelsey Hayes Co Automatic brake adjusting mechanism
US3532193A (en) * 1967-04-13 1970-10-06 Alfed Teves Gmbh Duo-duplex internal expansion brake
US3744595A (en) * 1970-08-14 1973-07-10 Girling Ltd Vehicle drum brakes

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3952845A (en) * 1974-02-16 1976-04-27 Girling Limited Brake adjusters
US4056175A (en) * 1975-09-30 1977-11-01 Girling Limited Slack adjusters for the shoes of vehicle shoe drum brakes of the duo servo type
US4085830A (en) * 1975-10-03 1978-04-25 Girling Limited Automatic slack adjusters for vehicle brakes
US4369863A (en) * 1979-08-31 1983-01-25 Lucas Industries Limited Internal shoe drum brakes for vehicles
US4537293A (en) * 1980-12-09 1985-08-27 Automotive Products Plc Hydraulic cylinder assemblies
US4535875A (en) * 1982-03-09 1985-08-20 Lucas Industries, Public Limited Company Actuator for an internal shoe drum brake
US4792021A (en) * 1982-03-26 1988-12-20 Nissin Kogyo Kabushiki Kaisha Self-compensating device for a drum brake
US4742897A (en) * 1985-11-29 1988-05-10 Akebono Brake Industry Company, Ltd. Wheel cylinder with self-contained auto-adjuster
US4986394A (en) * 1986-06-26 1991-01-22 Lucas Industries Brake actuator
US4887697A (en) * 1986-09-26 1989-12-19 Lucas Industries Public Limited Company Brake actuator
EP1013959A1 (de) * 1998-12-17 2000-06-28 Volkswagen Aktiengesellschaft Hydraulisch betriebener Radbremszylinder zur Betätigung der Bremsbacken einer Trommelbremse
US6325181B1 (en) 1999-07-30 2001-12-04 Kelsey-Hayes Company Piston assembly for use in a wheel cylinder of a drum brake assembly
EP1160475A2 (en) * 2000-06-01 2001-12-05 Nisshinbo Industries, Inc. Dual mode drum brake device
EP1160475A3 (en) * 2000-06-01 2003-05-28 Nisshinbo Industries, Inc. Dual mode drum brake device
US6763919B2 (en) 2000-06-01 2004-07-20 Nisshinbo Industries Inc. Dual mode drum brake device
US6454057B2 (en) * 2000-08-01 2002-09-24 Nisshinbo Industries Inc. Brake cylinder
US20100044165A1 (en) * 2006-07-31 2010-02-25 Vasil Argirovski Compact Disc-Brake Unit For Vehicles On Rails
US8794393B2 (en) * 2006-07-31 2014-08-05 POLI Costruzione Materiali Trazione S.R.L. Compact disc-brake unit for vehicles on rails
US11300170B2 (en) * 2017-10-12 2022-04-12 Continental Teves Ag & Co. Ohg Spreader unit for a drum brake, comprising wear travel adjustment, and the drum brake

Also Published As

Publication number Publication date
IT979719B (it) 1974-09-30
JPS48100566A (zh) 1973-12-19
FR2175439A5 (zh) 1973-10-19
GB1418681A (en) 1975-12-24
AU5263973A (en) 1975-06-12
DE2310608C2 (de) 1983-10-06
DE2310608A1 (de) 1973-09-06

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