GB1567076A

GB1567076A – Disc brake
– Google Patents

GB1567076A – Disc brake
– Google Patents
Disc brake

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Publication number
GB1567076A

GB1567076A
GB320577A
GB320577A
GB1567076A
GB 1567076 A
GB1567076 A
GB 1567076A
GB 320577 A
GB320577 A
GB 320577A
GB 320577 A
GB320577 A
GB 320577A
GB 1567076 A
GB1567076 A
GB 1567076A
Authority
GB
United Kingdom
Prior art keywords
lever
brake
lever plate
bolts
disc
Prior art date
1974-02-18
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

Application number
GB320577A
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.)

Deutsche Perrot Bremse GmbH

Original Assignee
Deutsche Perrot Bremse 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.)
1974-02-18
Filing date
1977-01-26
Publication date
1980-05-08

1974-08-12
Priority claimed from DE2438670A
external-priority
patent/DE2438670C3/en

1977-01-20
Priority claimed from AT34777A
external-priority
patent/AT365754B/en

1977-01-26
Application filed by Deutsche Perrot Bremse GmbH
filed
Critical
Deutsche Perrot Bremse GmbH

1980-05-08
Publication of GB1567076A
publication
Critical
patent/GB1567076A/en

Status
Expired
legal-status
Critical
Current

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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

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

F16D65/567—Slack adjusters mechanical self-acting in one direction for adjusting excessive play with screw-thread and nut for mounting on a disc brake

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

F16D55/00—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes

F16D55/02—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members

F16D55/22—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads

F16D55/228—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads with a separate actuating member for each side

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

F16D65/567—Slack adjusters mechanical self-acting in one direction for adjusting excessive play with screw-thread and nut for mounting on a disc brake

F16D65/568—Slack adjusters mechanical self-acting in one direction for adjusting excessive play with screw-thread and nut for mounting on a disc brake for synchronous adjustment of actuators arranged in parallel

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

F16D55/00—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes

F16D2055/0075—Constructional features of axially engaged brakes

F16D2055/0091—Plural actuators arranged side by side on the same side of the rotor

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

F16D2121/00—Type of actuator operation force

F16D2121/02—Fluid pressure

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

F16D2121/00—Type of actuator operation force

F16D2121/14—Mechanical

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

F16D2123/00—Multiple operation forces

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

F16D2125/00—Components of actuators

F16D2125/18—Mechanical mechanisms

F16D2125/20—Mechanical mechanisms converting rotation to linear movement or vice versa

F16D2125/22—Mechanical mechanisms converting rotation to linear movement or vice versa acting transversely to the axis of rotation

F16D2125/28—Cams; Levers with cams

F16D2125/32—Cams; Levers with cams acting on one cam follower

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

F16D2125/00—Components of actuators

F16D2125/18—Mechanical mechanisms

F16D2125/58—Mechanical mechanisms transmitting linear movement

F16D2125/60—Cables or chains, e.g. Bowden cables

Description

(54) DISC BRAKE
(71) We, DEUTSCHE PERROT
BREMSE GMBH, of 68 Mannheim 71,
Federal Republic of Germany, a German
Company, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a hydraulic disc brake having an additional mechanically operated parking brake, and is concerned with an improvement in or modification of an invention described and claimed in the
Complete Specification of our United Kingdom Patent Application No. 4148/75, (Serial
No. 1 490 795).
In one embodiment described in the said
Complete Specification (the parent specification) the levers for operating the mechanical brake are driven by a common lever plate by means of bolts engaging holes in the lever plate. The lever plate is rotated, against the action of a return spring, by a draw rod or cable. One of the holes must be in the form of a slot in order to provide the necessary movement clearance for the reciprocal rotations. When the brake lining carriers are changed because of wear on the brake linings, a brake of this type must be completely dismantled.
In contrast thereto the problem underlying the present invention is that of reducing the expense of dismantling for the purpose of changing the lining carriers, by providing a construction which is still more advantageous in respect of servicing. According to the invention this problem is solved in that the driving connection between each of the two levers and the lever plate is by meal, of a spigot which engages a slot which is provided in the lever plate and is open to the periphery of the latter. In this arrangement the complete dismantling of the brake is not necessary for the purpose of changing the brake lining carriers, but it is sufficient to release the spring and to turn the levers until they pass out of the lever plate. When in accordance with a preferred embodiment stops are provided for securing the zero position of the lever plate, it is expedient to use removable stops.
Further details and advantages of the invention will be seen from the following description and from the drawings, in which:
Figure 1 is a side view of a brake according to the invention,
Figure 2 is a plan view of the brake of
Figure 1, and
Figure 3 is a section in a plane III–III, which has a plurality of breaks, in Figure 2.
The brake shown comprises a brake saddle 1 which is equipped with two pairs of pistoncylinder units 2 and 3. Between the pistoncylinder units 2 and 3 forming respective pairs extends a brake disc 4 which is mounted on the axle which is to be braked. Viewing along the brake disc 4, a mechanical parking brake device 5, which is activated by the turning of levers 7 and 8, lies between the two pairs of piston-cylinder units 2, 3. The levers 7 and 8 are anchored on respective shafts 9 and 10.
The components of the mechanical parking brake device are entirely identical on each side of the brake disc, so that only one side thereof will be described.
The shaft 9 is mounted in bushes 12 and 13 in the brake saddle and is sealed in relation to the outside. In an axial bore 14, parallel to the axis of the brake, in the brake saddle are accommodated the brake parts necessary for clean engagement and also an automatic adjusting device. In its middle region the lever shaft 9 has a flat 15 co-operating with a pressure element or piston 16. The end of the flat, viewed in the peripheral direction, forms an edge 17 extending along a generatrix of the lever shaft 9. The piston 16 is frictionally connected by way of an automatic adjusting device, provided with an adjusting nut 21, to a lining carrier 18 and a brake lining 19. The two levers 7 and 8 are mounted on the respective lever shaft 9 or 10 so as to lie approximately in the axial direction of the brake and are turned in the same direction for the purpose of operating the latter.
A lever plate 31 made of strong sheet metal is connected pivotally and freely moveably to the levers 7 and 8 by means of spigots which are bolts 32 and 33 respectively. The points at which the bolts 32 and 33 act and two additional force application points lying one on each side of the line connecting those points form a rectangle configuration. The contour of the plate nevertheless has indented lateral lines, which for constructional reasons do not form a movement-limiting stop on the other components up to the maximum rotation of the lever plate 31. One of the two corners of the rectangular configuration where the bolts 32, 33 are not situated, namely at an action point 36, a draw rod 37 acts on the lever plate 31, the direction of its pull being approximately parallel to the line connecting the two bolts 32, 33 when the lever is in the middle position. By its pulling action the draw rod 37 effects the rotation of the lever plate 31 in succession or simultaneously about the bolts 32 and 33, which consequently slide laterally, and thus the pivoting of the levers 7 and 8 in the braking direction. Finally, at an action point 38 in the remaining corner of the rectangular configuration of the lever plate 31 a tension spring 39 acts, its action tending to turn the lever plate 31 oppositely to the action of the draw rod 37. At its other end the tension spring 39 is anchored in a stationary position on a bolt 42. The bolt 42 serves at the same time as a stop for a laterally projecting beak 41 on the lever 8, oppositely to the pivoting direction of the lever 8 for actuating the brake. The lever 7 has a beak 43 which in the zero position lies against a stop in the form of a bolt 44. The action of the beak 41 bearing against the bolt and of the beak 43 bearing against the bolt 44 enables the tension spring 39 to hold the lever system in a zero position, corresponding to the released position of the brake, irrespective of a corresponding position of the rest of the draw rod 37.
When the brake is actuated by pulling back the draw rod 37, the levers 7 and 8 are pivoted by means of the lever plate 31, against the force of the tension spring 39 and with the lever plate 31 supported on the bolt 32, until the brake linings 19 come to bear against the brake disc 4. If the brake linings are not applied simultaneously against the disc, the fixed centre of rotation will always be that articulation point formed by the bolt 32 or
33 on whose side of the disc the brake lining first comes into contact. Through a certain dissymmetrical distortion of the rectangle 32, 36, 33, 38 the different forces and counterforces, the spring constants, and if necessary the flat 16 can be mutually adapted.
The bolts 32 and 33 engage slots 45 and 46 respectively which are provided in the lever plates 31 and which are cut into the latter from its periphery. The slot 45 is sufficiently elongated to compensate for the variation of distance between the bolts 32 and 33
resulting from the pivoting of the levers 7 and
8. The elongated slot 45 is provided on the opposite side to the direction in which the draw rod 37 acts, because the lever plate must be supported by the slot 46 on the bolt 33 when a pull is applied to it.
The engagement of the bolts 32, 33 in the slots 45, 46 which are open on the outside provide the advantage of easier maintenance, because complete dismantling is not necessary when it is required to change the brake lining carriers. After the bolts 42 and 44 forming the stops have been screwed out and the adjusting nut 21 (Figure 3) has been screwed back sufficiently far to enable the edge 17 of the flat 15 of the lever shaft 9 to be turned past the rear surface of the piston 16 in the clockwise direction and after the tension spring 39 has been disconnected, a lever plate 31 can be turned until the bolts 32 and 33 come out of the slots 45 and 46 and the lever plate can be taken out sideways. In the case of disc brakes which are not provided with an automatic adjusting device and in which the brake linings are still sufficiently fixed to prevent the edge 17 from moving past the rear side of the pressure element 16, the corresponding increased clearance can be obtained by other means known to the specialist, for example with the aid of a key which can be driven out of the path of force transmission, in accordance with UK patent Specification No.
1 203 173.
WHAT WE CLAIM IS: – 1. A hydraulic disc brake having a pair of mechanical parking brakes which lie opposite one another and which have their own brake linings, an actuating device common to the pair being a lever plate drivingly connected to two levers associated respectively with the parking brakes, the lever plate being rotatable by a draw rod and a return spring acting in different senses of rotation, each lever having a lever shaft disposed perpendicularly to the brake axis and each lever shaft engaging by means of a cam surface with a pressure member of a movable thrust device constraining the brake linings to be applied to or released from the brake disc, characterised in that the driving connection between the lever plate and each lever is made up by a spigot on each lever slidingly engaged in a slot in the lever plate which opens to the periphary of the latter.
2. A disc brake according to Claim 1 wherein the draw rod and the return spring act in parallel in substantially the same direction on the lever plate at respective points which lie on different sides of the line connecting the two points at which the levers are drivingly connected to the plate, and that the slot opening away from the direction in which the draw rod and spring act is cut into the lever plate inwards to beyond the point where that spigot can engage.
3. A disc brake according to Claim 1 or
Claim 2, in which the lever plate or its levers
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. points at which the bolts 32 and 33 act and two additional force application points lying one on each side of the line connecting those points form a rectangle configuration. The contour of the plate nevertheless has indented lateral lines, which for constructional reasons do not form a movement-limiting stop on the other components up to the maximum rotation of the lever plate 31. One of the two corners of the rectangular configuration where the bolts 32, 33 are not situated, namely at an action point 36, a draw rod 37 acts on the lever plate 31, the direction of its pull being approximately parallel to the line connecting the two bolts 32, 33 when the lever is in the middle position. By its pulling action the draw rod 37 effects the rotation of the lever plate 31 in succession or simultaneously about the bolts 32 and 33, which consequently slide laterally, and thus the pivoting of the levers 7 and 8 in the braking direction. Finally, at an action point 38 in the remaining corner of the rectangular configuration of the lever plate 31 a tension spring 39 acts, its action tending to turn the lever plate 31 oppositely to the action of the draw rod 37. At its other end the tension spring 39 is anchored in a stationary position on a bolt 42. The bolt 42 serves at the same time as a stop for a laterally projecting beak 41 on the lever 8, oppositely to the pivoting direction of the lever 8 for actuating the brake. The lever 7 has a beak 43 which in the zero position lies against a stop in the form of a bolt 44. The action of the beak 41 bearing against the bolt and of the beak 43 bearing against the bolt 44 enables the tension spring 39 to hold the lever system in a zero position, corresponding to the released position of the brake, irrespective of a corresponding position of the rest of the draw rod 37. When the brake is actuated by pulling back the draw rod 37, the levers 7 and 8 are pivoted by means of the lever plate 31, against the force of the tension spring 39 and with the lever plate 31 supported on the bolt 32, until the brake linings 19 come to bear against the brake disc 4. If the brake linings are not applied simultaneously against the disc, the fixed centre of rotation will always be that articulation point formed by the bolt 32 or 33 on whose side of the disc the brake lining first comes into contact. Through a certain dissymmetrical distortion of the rectangle 32, 36, 33, 38 the different forces and counterforces, the spring constants, and if necessary the flat 16 can be mutually adapted. The bolts 32 and 33 engage slots 45 and 46 respectively which are provided in the lever plates 31 and which are cut into the latter from its periphery. The slot 45 is sufficiently elongated to compensate for the variation of distance between the bolts 32 and 33 resulting from the pivoting of the levers 7 and 8. The elongated slot 45 is provided on the opposite side to the direction in which the draw rod 37 acts, because the lever plate must be supported by the slot 46 on the bolt 33 when a pull is applied to it. The engagement of the bolts 32, 33 in the slots 45, 46 which are open on the outside provide the advantage of easier maintenance, because complete dismantling is not necessary when it is required to change the brake lining carriers. After the bolts 42 and 44 forming the stops have been screwed out and the adjusting nut 21 (Figure 3) has been screwed back sufficiently far to enable the edge 17 of the flat 15 of the lever shaft 9 to be turned past the rear surface of the piston 16 in the clockwise direction and after the tension spring 39 has been disconnected, a lever plate 31 can be turned until the bolts 32 and 33 come out of the slots 45 and 46 and the lever plate can be taken out sideways. In the case of disc brakes which are not provided with an automatic adjusting device and in which the brake linings are still sufficiently fixed to prevent the edge 17 from moving past the rear side of the pressure element 16, the corresponding increased clearance can be obtained by other means known to the specialist, for example with the aid of a key which can be driven out of the path of force transmission, in accordance with UK patent Specification No.

1 203 173.
WHAT WE CLAIM IS: – 1. A hydraulic disc brake having a pair of mechanical parking brakes which lie opposite one another and which have their own brake linings, an actuating device common to the pair being a lever plate drivingly connected to two levers associated respectively with the parking brakes, the lever plate being rotatable by a draw rod and a return spring acting in different senses of rotation, each lever having a lever shaft disposed perpendicularly to the brake axis and each lever shaft engaging by means of a cam surface with a pressure member of a movable thrust device constraining the brake linings to be applied to or released from the brake disc, characterised in that the driving connection between the lever plate and each lever is made up by a spigot on each lever slidingly engaged in a slot in the lever plate which opens to the periphary of the latter.

2. A disc brake according to Claim 1 wherein the draw rod and the return spring act in parallel in substantially the same direction on the lever plate at respective points which lie on different sides of the line connecting the two points at which the levers are drivingly connected to the plate, and that the slot opening away from the direction in which the draw rod and spring act is cut into the lever plate inwards to beyond the point where that spigot can engage.

3. A disc brake according to Claim 1 or
Claim 2, in which the lever plate or its levers
is or are held, in the direction of rotation in which it is or they are urged by the return spring, by two stops in a limit position which corresponds to the brake release position, the stops being removable.

4. A disc brake substantially as herein described with reference to and as illustrated in the accompanying drawings.

GB320577A
1974-02-18
1977-01-26
Disc brake

Expired

GB1567076A
(en)

Applications Claiming Priority (3)

Application Number
Priority Date
Filing Date
Title

DE2407670

1974-02-18

DE2438670A

DE2438670C3
(en)

1973-08-14
1974-08-12

Electric dust collector

AT34777A

AT365754B
(en)

1974-02-18
1977-01-20

HYDRAULIC DISC BRAKE WITH ADDITIONAL MECHANICAL PARKING BRAKE

Publications (1)

Publication Number
Publication Date

GB1567076A
true

GB1567076A
(en)

1980-05-08

Family
ID=27146186
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

GB320577A
Expired

GB1567076A
(en)

1974-02-18
1977-01-26
Disc brake

Country Status (1)

Country
Link

GB
(1)

GB1567076A
(en)

1977

1977-01-26
GB
GB320577A
patent/GB1567076A/en
not_active
Expired

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Legal Events

Date
Code
Title
Description

1980-07-23
PS
Patent sealed

1987-09-16
PCNP
Patent ceased through non-payment of renewal fee

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