GB2185297A - Internal shoe drum brake - Google Patents
Internal shoe drum brake Download PDFInfo
- Publication number
- GB2185297A GB2185297A GB08600453A GB8600453A GB2185297A GB 2185297 A GB2185297 A GB 2185297A GB 08600453 A GB08600453 A GB 08600453A GB 8600453 A GB8600453 A GB 8600453A GB 2185297 A GB2185297 A GB 2185297A
- Authority
- GB
- United Kingdom
- Prior art keywords
- brake
- lever
- shoe
- ofthe
- drum
- 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- Withdrawn
Links
Classifications
-
- 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
- F16D51/00—Brakes with outwardly-movable braking members co-operating with the inner surface of a drum or the like
- F16D51/16—Brakes with outwardly-movable braking members co-operating with the inner surface of a drum or the like shaped as brake-shoes pivoted on a fixed or nearly-fixed axis
- F16D51/18—Brakes with outwardly-movable braking members co-operating with the inner surface of a drum or the like shaped as brake-shoes pivoted on a fixed or nearly-fixed axis with two brake-shoes
- F16D51/20—Brakes with outwardly-movable braking members co-operating with the inner surface of a drum or the like shaped as brake-shoes pivoted on a fixed or nearly-fixed axis with two brake-shoes extending in opposite directions from their pivots
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Braking Arrangements (AREA)
Abstract
An internal shoe drum brake includes a hand brake lever 19 pivotally disposed with respect to one brake shoe 11 and acting on one end of the rigid strut 25, the other end of the strut engaging the other shoe 12. One end 21 of the hand brake lever 19 is disposed between the end 24 of the web portion 20 of brake shoe 11 and an abutment 23, so as to permit pivotting between the hand brake lever 19 and abutment 23 and the hand brake lever 19 and end 24 of brake shoe 11 respectively. <IMAGE>
Description
SPECIFICATION
Drum brakes
The present invention relates to drum brakes and in particular to internal shoe drum brakes suitable for motor vehicles.
An internal shoe drum brake normally includes a fixed back plate, a pair of arcuate brake shoes mounted on the back plate, expanding means for urging the brake shoes apart generally radially ofthe back plate and a rotatable brake drum, coaxial with the back plate, and against which the brake shoes act.
Such brakes may have independent service brake and parking brake expanding means. By service brake we mean the primary vehicle braking system, usually hydraulically actuable, and by parking brake the secondary vehicle braking system, usually mechanically actuable.
The present invention is particularly concerned with the parking brake actuator, which comprises a lever pivotally associated with one of the brake shoes and connected to the other shoe by means of a rigid strut.
According to one aspect ofthe present invention, an internal shoe drum brake comprises a pair of arcuate brake shoes with service brake expanding means disposed between adjacent ends of said brake shoes, a parking brake actuating lever having an end portion pivotally interposed between the end of one brake shoe and an abutment, and a rigid strut engaging between the hand brake lever at a position spaced from said end portion, and the other brake shoe.
Preferablythe abutment is provided by the service brake expanding means and may be formed by the head of the piston of a hydrauliccylinder/piston actuator.
An embodiment of the invention is now described, by way of example only, with reference to the accompanying drawings, in which:
Figure lisa part sectional view of a drum brake formed in accordance with the present invention;
Figure2 is a part section along the line ll-ll in
Figure 1; and Figure3is a partsectional view along the line Ill-Ill in Figure 1.
As illustrated in Figure 1, an internal shoe drum brake assembly comprises a pair of brake shoes 11 and 12 mounted on a back plate 13. The brake shoes 11 and 12 may be urged apart bya service brake expander in the form of a double acting hydraulic cylinder 14, abouta fixed abutment 15. Pull-off springs 16 and 17 are provided to return the brake shoes 11 and 1 to their inoperative position. A rotatable hub 18 carries a brake drum (not shown) which is coaxial with the backing plate 13.
As illustrated in Figures 1 to 3, a hand brake lever 19 is mounted against the web portion 20 ofshoe 11.
The end 21 of lever 19 is cranked awayfrom the web portion 20 and is bent to form a U-shaped portion 22, the limbs 22a of which lie one on either side ofthe web portion 20 and the curved interconnecting section 22b ofwhich is interposed between the piston 23 of hydraulic cylinder 14andthe end 24of web portion 20. The portion of lever 19 interposed between the piston 23 and the web portion 20 is radiused in the plane of movement of lever 19, so that the lever 19 will pivot on the flat end of piston 23.
The end 24 of web portion 20 is also radiused, its radius being smaller than the radius ofthe portion of the lever 19 it abuts, so that lever 19 will also pivot relative to the web portion 20.
A rigid cross strut 25 engages between a notch 26 in the lever 19 and a notch 27 in theweb portion 28Of shoe 12. Acoupling formation 29 is provided at the other end of lever 1 9, by means of which it may be connected via, for example a cable, to the hand brake actuating lever.
Upon application ofthe hand brake, the lever 19 is pivotted clockwise, as viewed in Figure 1, section 22b of lever 19 rocking on the end of piston 23. The rigid cross strut 25 is thereby urged towards shoe 12 and moves shoe 12 into engagement with the brake drum. Once shoe 12 engages the brake drum, continued movement of lever 19 pivots it about the end of cross strut 25, so that the section 22b of lever 19 acting against the end 23 of shoe 11 forces shoe 11 into engagement with the brake drum.
Upon release of the hand brake, the shoes are retracted to the position illustrated in Figure 1, by means ofthe pull-offsprings 16 and 17.
When the brake is in the inoperative position, as illustrated in Figure 1, orthe hand brake is applied, the cross strut 25 will be in compression and will thus be maintained in engagement with the notches 26 and 27. However, when the service brake is applied bymeansofthehydrauliccylinderl4, movement of the shoes 11 and 12 will increase the separation of notches 26 and 27 and the strut 25 will become loose. Spring means (not shown) may be provided to maintain the strut 25 in engagement with lever 19, when the brake is in this condition.
Furthermore, automatic wear adjusters of conventional design may be included to adjustthe effective length of the strut 25, to compensate for wear of the friction linings ofthe shoes 11 and 12.
Various modifications may be made without departing from the invention. For example while in the above embodimentsection 22b of lever 19is radiusedand actsagainsttheflatend of piston 23, section 22b may be flat and the end of the piston 23 radiused. Also, while the limbs 22a of the U-shaped formation 22 serve to locate the lever 19 with respect to the web portion 20 of shoe 11 this is not an essential feature of the invention. Other formations which will permitthe interposition of a portion ofthe lever between the brake shoe and an abutment, in a mannerwhich will allow pivoting ofthe lever, for example a simpleflangeformation, may be used.
1. An internal shoe drum brake comprising a pair of arcuate brake shoes with service brake expanding means disposed between adjacent ends of said brake shoes, a parking brake actuating lever having an end portion pivotally interposed between the end of one brake shoe and an abutment, and a rigid strut
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (11)
1. An internal shoe drum brake comprising a pair of arcuate brake shoes with service brake expanding means disposed between adjacent ends of said brake shoes, a parking brake actuating lever having an end portion pivotally interposed between the end of one brake shoe and an abutment, and a rigid strut engaging between the hand brake lever at a position spaced from said end portion, and the other brake shoe.
2. An internal shoe drum brake as claimed in claim 1 in which the abutment is provided bythe service brake expanding means.
3. An internal shoe drum brake according to claim 2 in which the service brake expanding means is a hydraulic cylinder/piston actuator, the abutment being provided by the head ofthe piston.
4. An internal shoe drum brake according to any one of claims 1 to 3 in which the surface ofthe lever in engagementwith the abutment, is radiused in the plane of movement of the lever.
5. An internal shoe drum brake according to any one of claims 1 to 4 in which the end portion ofthe lever is interposed between the abutment and the end portion of the web of the brake shoe.
6. An internal shoe drum brake according to claim Sin which the end portion ofthe web is radiused relative to the surface of the end portion of the lever with which it engages.
7. An internal shoe drum brake according to claim 6 in which both the end portion of the web and the end portion ofthe lever are radiused,the radius ofthe end portion oftheweb being smaller than the radius ofthe end portion ofthe lever.
8. An internal shoe drum brake as claimed in any one of Claims 5 to 7 in which the end portion ofthe lever defines a U-shaped formation, the parallel limbs of this formation lying one on either side ofthe web portion of the shoe and the curved interconnecting portion ofthe formation being interposed between the end ofthe web portion ofthe shoe and said abutment.
9. An internal shoe drum brake as claimed in any one ofthe preceeding claims in which spring means is provided for maintaining the rigid strut in engagement with the parking brake actuating lever.
10. An internal shoe drum brake as claimed in any one of claims 1 to 9 in which an automaticwear adjuster is associated with the rigid strutto adjust the effective length ofthe strut as the friction linings of the brake shoes wear.
11. An internal shoe drum brake substantially as described herein with reference to and as shown in, figures 1 to 3 of the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08600453A GB2185297A (en) | 1986-01-09 | 1986-01-09 | Internal shoe drum brake |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08600453A GB2185297A (en) | 1986-01-09 | 1986-01-09 | Internal shoe drum brake |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8600453D0 GB8600453D0 (en) | 1986-02-12 |
| GB2185297A true GB2185297A (en) | 1987-07-15 |
Family
ID=10591110
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08600453A Withdrawn GB2185297A (en) | 1986-01-09 | 1986-01-09 | Internal shoe drum brake |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2185297A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0393211A1 (en) * | 1989-04-17 | 1990-10-24 | LUCAS INDUSTRIES public limited company | Drum brake for a motor vehicle, comprising a parking brake |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114321271B (en) * | 2021-12-27 | 2024-01-30 | 济南弘正科技有限公司 | High-stability clutch sleeve plate for reducing vehicle vibration and abnormal sound |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0014632A1 (en) * | 1979-02-02 | 1980-08-20 | The Bendix Corporation | Improved drum brake assembly |
-
1986
- 1986-01-09 GB GB08600453A patent/GB2185297A/en not_active Withdrawn
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0014632A1 (en) * | 1979-02-02 | 1980-08-20 | The Bendix Corporation | Improved drum brake assembly |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0393211A1 (en) * | 1989-04-17 | 1990-10-24 | LUCAS INDUSTRIES public limited company | Drum brake for a motor vehicle, comprising a parking brake |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8600453D0 (en) | 1986-02-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5275260A (en) | Dual mode drum brake assembly | |
| CA2025421C (en) | Leading/trailing drum brake having servo parking brake | |
| US3811537A (en) | Shoe drum brakes | |
| EP0258625B1 (en) | S cam for drum brake | |
| KR830001660B1 (en) | Car drum brake | |
| US3621947A (en) | Vehicle drum brakes and adjusting means therefor | |
| US3575266A (en) | Self-adjusting parking brake | |
| GB2185297A (en) | Internal shoe drum brake | |
| US6065571A (en) | Drum brake system and device | |
| US1984883A (en) | Brake | |
| US4051928A (en) | Automatic shoe clearance adjusting device in shoe drum brake | |
| US3658159A (en) | Brake device | |
| US3913710A (en) | Shoe drum brakes | |
| CA1060813A (en) | Brake construction | |
| JP3413459B2 (en) | Drum brake device | |
| JPS6138235A (en) | Automatic brake regulating mechanism | |
| US6739434B1 (en) | Linkage for joining a lever to a brake cable | |
| EP0049583B1 (en) | Automatic wear adjuster for drum brakes | |
| GB2058970A (en) | Automatic wear adjuster for drum brakes | |
| US4424888A (en) | Shoe and drum brake | |
| US2152923A (en) | Wheel brake | |
| US5484042A (en) | Fluid pressure and mechanical drum brake actuator | |
| US6499569B1 (en) | Damped anchor shim for drum brake assembly | |
| AU645675B2 (en) | Drum brake actuator | |
| EP0237158A1 (en) | Improvements in self-energising disc brakes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |