DE8303722U1 - ADJUSTMENT AND CENTERING DEVICE FOR SERVO BRAKES - Google Patents

Description

Maschinenbau Knott Eggstätt Ing.Valentin Knott, 8201 Eggstätt

235 P 6

Adjustment and centering device for servo brakes

The invention relates to a centering and adjusting device for servo brakes according to the preamble of the claim

1.

Be one of DE-GM 72 19 84 known Nachstel I- and centering device on a sliding lock of an inner jaw servo brake is only one adjusting device effective in one direction, which for this purpose comprises an adjusting lever with an adjusting pawl, which engages in a one-sided locking toothing of a NachstelI gear.

-2-

When the sliding lock is pushed through, the adjusting lever is moved by one on the guide block provided pivot axis pivoted outward so that the pawl initially engages a tooth and at the subsequent centering of the sliding lock brought about by the spring force and thus the reverse Circumferential movement engages the previously locked tooth and the adjustment sleeve in the sense of unscrewing of the threaded bolt twisted. To actuate the adjusting lever, one can be moved along with the sliding lock Approach provided, which cooperates with a stop on the adjustment lever for pivoting. The declining Circumferential movement of the plate-shaped adjusting lever is carried out on the one hand on a transverse arm of the adjusting lever acting and on the other hand anchored on the guide block causes return spring. The adjuster is secured! on a bolt serving as a pivot axis by means of a cross hole through the bolt bracket clip protruding through.

However, this adjustment and centering device has serious problems Disadvantages on. On the one hand, in practice, in particular in the case of commercial vehicles, with relative high braking torques and in turn with rev <irsierendem operational use shown that the operational safety such an adjustment device to meet today's requirements is no longer sufficient. This is possible with this previously known adjusting device in particular with sworn Vibrations, that the following lever swings outwards due to these vibrations and thus without Necessity a next tooth of the adjusting gear engages behind and makes an adjustment.

■ · · Α · »Il * M I

ti · ι mi · · · ·

-3-

Furthermore, the return springs are also subject to some wear exposed, so that their restoring forces change in the event of extensive and intensive stress. On the other hand, with such adjusting and centering devices, it is also possible that during a pushing-through movement of the sliding lock, the adjusting lever is initially pivoted outward, while doing so but the adjusting gear easily carries along, so that a There is no reaching behind a next tooth and thus the desired readjustment cannot be achieved can. These adverse effects occur in particular in heavy commercial vehicles with great wear and tear and a lot of dirt on the adjustment device on. Finally, the one at the front |

known adjusting device took up space by |

the laterally upwardly projecting lever arm, on which the return spring attaches, is relatively large.

In contrast, it is the object of the invention to overcome these disadvantages according to the prior art and an adjustment and to create a centering device with increased operational safety and performance without this the required installation space becomes larger.

The object is according to the \

characterizing part of claim 1 or 2 specified ϊ

Features solved. Advantageous refinements in the sense the task are specified in the subclaims. I.

. ■ I

In the adjusting and centering device according to the invention i

For the first time, there will be no return spring for servo brakes

-4-

• * · t · · itii

Ill Il

-4-

more needed for the next lever. According to the invention the resetting of the adjuster I hebeis is also taken over by the centering spring. For this purpose, the sliding lock a restoring approach that can be moved along with it, with one in the adjustment lever in the opposite direction cooperates with the second stop located at the first stop and about this in a reverse centering H of the sliding lock, move the adjuster lever to its

§ returns the situation. Because of this arrangement,

| S 10 not only in an advantageous manner the return spring as

^ such superfluous, but rather the after-

] S adjusting lever itself held in this initial position, so that

fcj outward pivoting becomes impossible.

■; '.'. 15 Corch the present invention is also used

■ \: in an advantageous manner by eliminating an additional

ji chen remnants! , spring reduces the space required.

i \ In an alternative embodiment according to claim 2

: · 20 will be operational safety and efficiency

increased by the fact that an anchored in the guide block

• ί locking bracket is provided with its end between

k! two adjacent teeth of the locking teeth of the rear

Ui adjusting gear is held in place. Even with one

ψ '25 will initially swing the adjuster lever outward

Γ, which means that the adjusting gear does not move with it and is safe

held so that when a certain height of the adjustment lever is reached, a secure grip behind of a next tooth and a continuation is possible. 30th

An advantageous embodiment according to claim 3 combines the advantageous features according to claims 1 and 2 and concerns an automatic adjustment and centering device

for a servo brake without additional return springs and with a locking bracket that engages on the adjusting gear.

In a development according to claim 4 is the invention Device designed so that readjustment in both push-through directions of the push-through lock is made possible. It is true that DE-OS 31 12 550 a double-acting adjustment and centering device for an 'inner jaw servo brake became known as such. This also with a separate return spring to return the adjustment lever! provided device but also has the disadvantages cited at the beginning.

In an advantageous embodiment of the invention according to claim 5, it is provided that the adjustment attachment, which can be moved along with the slide lock against the force of the centering spring, for pivoting out and the return attachment for returning the adjustment lever are designed as a common part, whereby in a further development according to claim 6, this common actuation approach in a corresponding recess in the next row '
engages, through which the two opposing stops for pivoting out and returning the adjusting lever are formed.

According to an embodiment according to claim 8, an additional elastic suspension is advantageously forgotten, with the adjustment lever! towards the assigned adjusting gear is pressed on. Even

in the event of enormous loads and vibrations operational safety is further increased.

-6-

A further improvement can still be achieved according to claim 9 in that the front part of the Adjusting lever forming adjusting pawl compared to this is so angled that it engages behind a ratchet tooth deeper.

Better engagement of the adjuster pawl on the adjuster gear is finally also made possible by an embodiment according to claim 10 by the adjusting pawl is designed cranked to the adjusting lever and the Nachstel Gearwheel essentially has a diameter which corresponds to the width of the guide bracket. Through this Smaller dimensions not only take up less space, but above all the engagement conditions between the adjuster pawl and adjuster gear improved.

Further advantages, details and features of the invention emerge below with reference to FIG Description of the exemplary embodiments followed on the basis of the accompanying figures. The following show in detail:

Figure 1: a plan view of the adjustment according to the invention and centering device, partly in section;

FIG. 2: a side view according to FIG. 1;

FIG. 3: an end view;
30th

FIG. 4: an enlarged detail according to FIG. 2;

FIG. 5: a further embodiment of the readjusting and centering device according to the invention in side view and

-7-

FIG. 6: an end view according to FIG. 5.

In the following, reference is made to Figures 1 to 4, in which the automatic adjustment and centering device for a servo brake with a side view substantially U-shaped guide block 1, which is not in can be firmly connected to the brake cover plate or the brake carrier, as shown in more detail. In the guide block 1 a sliding lock is arranged in bores, which is displaceable in its axial direction and here the brake actuation force is transmitted from the respective primary jaw to the secondary jaw. This as the next I- and centering device serving sliding lock enlarged when the brake lining is worn on one of the Brake shoes its axial length in relation to the centered position in order to reduce the brake clearance for each of the two Keeping brake shoes constant.

For this purpose, it sits non-rotatably on the ends of the brake shoes Threaded bolt 3 which is screwed into one of the adjusting tube 5 assigned to the respective brake shoes. The adjustment tubes 5 are stepped on their opposite end faces and over one there each end face Connecting pipe 7 connected to each other. Furthermore, the Nachstel Irohre 5 are each in a sleeve surrounding them 9 rotatably mounted, which are arranged in the bores in the U-shaped guide block 1 and are longitudinally displaceable each have a flange 11 at their facing front ends. Adjacent to the flanges .11 a Nachstel I disk 13 is provided so that one is located between the adjusting disks 13 strong centering spring 15 on the adjusting disks 13 the

-8th-

Flanges 11 of the sleeves 9 at a distance and with their flanges in contact with the legs of the U-shaped guide block being held.

Furthermore, each adjusting tube 5 is firmly connected to an adjusting gear 17 which is arranged axially symmetrically with respect to this. The direction of a locking toothing on the adjuster gear 17 depends on the thread direction between the adjusting tube 5 and the threaded bolt 3 and is chosen so that a rotation to unscrew the Threaded bolt 3 leads when the adjusting gear 17 is taken along with a ratchet engagement.

Even if, in the embodiment shown, the two adjusting tubes with the adjusting gears arranged on them can easily be withdrawn axially, the effects introduced on a threaded bolt 3 nonetheless Braking forces pushing through the sliding lock due to the frontal contact between the first Adjuster tube, the connecting tube and the second adjuster Irohr.

As can be seen in particular from FIGS. 1 and 2, two on opposite sides are also rotated by 180 ° to one another lying adjuster! 19 are provided, each pivotable about a bolt 21 attached to the guide block 1 are. As can be seen in particular from FIG. 2, the bolts 21 serving as axes of rotation are to the Longitudinal axis of the sliding lock arranged offset.

Each adjustment lever 19 goes in at its front end an adjusting pawl 23 engaging in the respective adjusting gear 17, which connects to the adjusting lever itself is cranked and angled to its plane so that the front latching edge is deeper between two adjacent ones Teeth of the adjusting gear 17 can grip (Fig. 3).

-9-

A safe intervention of each post ikl inke 23 is but also made possible by the bolt lock 25 provided in each case with a spring washer 27 arranged underneath, wherein a washer 29 can also be provided in between. By being designed in the form of a disc spring The spring washer 27, which is supported on the pin retainer 25, exerts even greater axial forces on the adjustment lever 19 initiated, so that this with its Nachstel IkI inke 23 in an even more secure and secure engagement is held with the respective adjusting gear 17.

As can be seen in particular from FIG. 2, a recess 31 is provided in each adjusting lever 19 in this recess Axialricht'ing protruding into and opposite Stops 33 and 35 are provided. The stops 33 and 35 are each concave. Through the recess 31 also protrudes an actuating shoulder 37, which is part of the adjusting disk 13 in the exemplary embodiment shown.

The mode of operation of this automatic adjustment and centering device is explained below.

For example, through the brake shoes on the right Threaded bolt 3 initiated corresponding forces, the sliding lock is a total of right to left moved in guide block 1. In doing so, the right adjuster tube 5 and the right adjuster disk that is carried along 13 further compressed the strong centering spring '15. After overcoming a clearance 39, the touches Actuating attachment 37 the first stop 33 and thereby leads to a certain pivoting of the one shown in FIG Adjustment lever 19 clockwise.

-10-

I ■ · I

-10-

Since the pivoting increases with increasing pad wear, the next! Pawl 23 will eventually move a- %

Most tooth of the adjusting gear 17 reach over and engage, the locking movement being effected by the adjusting pawl 23 which is angled towards the adjusting gear 17 and their cranked training, as well as transverse forces introduced by the spring washer 27 on the bolt 21 on the Adjustment lever 19 is favored.

This will be the case when the brake is subsequently reset Slide lock moved back to the right into its starting position via the strong centering spring 15. After again Overcoming the clearance 39 is the actuating shoulder 37 with the adjusting disk moved to the right 13 come to rest on the second stop 35 and thus the following lever 19 in a counterclockwise direction with the force of the centering spring swivel back into its starting position. Through to the next Tooth locked adjusting pawl 23 is this adjusting gear 17 and thus the associated adjusting tube 5 rotated so that the left shown in the drawing Threaded bolt 3 is unscrewed.

As can be seen from the illustration shown in FIG. 2, the clearance 39 in the recess 31 is so small held that even with the strongest vibrations of the Nachstel I Hebel 19 are not pivoted clockwise can, but by the actuating shoulder 37 on the second, acted upon by the spring force of the centering spring 15 Stop 35 is held.

A corresponding shift of the sliding lock

-11-

■ -11-

in the opposite direction causes a corresponding Twisting of the opposite sleeve and ultimately an axial extension of the opposite threaded bushing 3.

Figures 5 and 6 will be discussed below, in which a further embodiment is shown.

As can be seen in particular from FIG. 5, there is also one anchored and held on the guide block 1 Locking bracket 41 is provided, which is essentially U-shaped and in side recesses 43 on the guide block '

1 is held. On one side of the recess 43 on one leg of the U-shaped guide block 1, the locking bracket protrudes 41 with its end cranked to the adjuster gear 17 to be cranked over this before and is between j see two adjacent teeth held in place * Fer- jj ner is in a transverse bore 47 in the guide block 1 ι

held locking bracket 41 in the direction of the adjustment \

gear 17 preloaded.

The locking bracket 41 is effective when the slide lock is pushed through and swiveled out accordingly of the adjustment lever 19, that the adjustment gear 17 is securely held and not rotated at the same time, to enable a fully functional readjustment. After the adjusting pawl 23 and the The adjustment lever 19 is returned to its starting position when the adjustment gear is rotated as a result 17 lifted the cranked end 45 out of the respective tooth position and automatically engages behind another tooth.

Claims (10)

Maschinenbau Knott Eggstätt Ing. Valentin Knott, 8201 Eggstätt P 6 Adjustment and centering device for servo brakes Claims: 1. Adjustment and centering device for a servo brake with a stationary one that is essentially U-shaped in a side view Guide block with a slide lock in its axial bores mounted axially displaceably from a central position against the force of a centering spring is, which comprises two threaded bolts, which are screwed into an adjusting tube · - with one axially symmetrical for this purpose arranged and a unilaterally acting locking toothing having adjusting gear fesc ver -01 is bound, in which one with a sliding movement of the sliding lock a circumferential movement on the adjuster! Ikiinke intervenes, which when pushed too far in the direction of the assigned brake shoe carries out an outward pivoting and engages a tooth and in the subsequent return of the sliding lock and reverse circumferential movement caused by the force of the centering spring, engages the previously locked tooth and the following! Pawl in the sense of a Unscrewing the threaded bolt twisted, work the adjuster pawl on another ! ! Lever is seated, which is held pivotably about a bolt arranged on the stationary brake part, preferably on the guide block, and for this purpose has a laterally offset stop in relation to its pivot axis, which is located in the path of movement of a pivoting extension which causes the adjustment lever to pivot outwards, which is moved with the sliding lock, characterized,
that the centering spring (15) also serves as a return spring and for this purpose a return attachment (actuation attachment 37) that moves along with the sliding lock is provided, which with a further on the adjustment lever (19) in the opposite direction to the first stop (33) acting second stop (35) cooperates that, after the sliding movement has taken place when the sliding lock is centered, the restoring projection (actuating projection 37) that is moved with it causes the adjusting lever (19) to pivot back into its starting position. 2. Adjusting and centering device according to the preamble of claim 1, characterized in that a locking bracket (41) anchored on the guide block (1) is provided, which has an 'end (45) between two adjacent- -02 ten teeth of the ratchet teeth of the adjuster gear (17) is held in place. 3. Adjusting and centering device according to claim 1, characterized in that, furthermore, one on the guide block (1) anchored locking bracket (41) is provided with one end (45) engaging between two adjacent teeth of the ratchet teeth of the adjusting gear (17) is held. 4. Adjusting and centering device according to claim 1, 2 or 3, characterized in that the adjusting device Acts in both push-through directions and for this purpose two rear end tubes (5) with one comprises connecting tube (7) arranged therebetween, each adjusting tube (5) having an adjusting gear wheel (17) in a rotationally fixed manner carries, in each of which an adjusting lever (19) with two stops (33; 35) acting in opposite directions engages, which alternately with a swiveling or reset approach that can be moved along with the sliding lock (Actuating approach 37) can be brought into engagement. 5. Adjusting and centering device according to claim 1, 3 or 4, characterized in that only a single actuating mechanism which can be moved along with the sliding lock approach (37) is provided, which serves as a pivoting and restoring approach and which engages between the associated first stop (33) and second stop (35) of the adjusting lever (19).
30th 6. Adjusting and centering device according to one of the claims 1 or 3 to 5 with a recess in the adjustment lever into which the stop for pivoting the Adjuster lever from the assigned adjuster! -03 »T · fl · t · • · · ti I ■ · lit 1 I • ■ I »II Tet in a preferably convexly curved shape and the swivel attachment which can be moved along with the sliding lock protrudes in the transverse direction, characterized in that opposite to the first stop (33) the second, preferably convex stop (35) protrudes into the recess (31), the distance between the two stops (33; 35) being the thickness of the intervening and serving as a pivoting and restoring approach actuation approach (37) plus provided Corresponds to the clearance (39). 7. Adjusting and centering device according to one of claims 1 or 3 to 6, characterized in that the The locking bracket (41) is arranged in the longitudinal direction in the guide block (1) and is essentially U-shaped and in the direction of the assigned adjusting gear (17) is biased. 8. Adjusting and centering device according to one of claims 1 or 3 to 7, characterized in that on the pivot axis of the adjusting lever (19) forming the pin (21) is fitted with a pin retainer (25) on which a spring washer (27) acting on the adjusting lever (19) is supported.
25th 9. integral action and centering device according to any one of claims 1 or 3 to 8, characterized in that the Nachstellklinke (23) countertransference the Nachstel Ihebel (19) gear (17) to abgwinkelt with their engagement edge to the Nachstel!. 10. Adjusting and centering device according to one of claims 1 or 3 to 9, characterized in that the diameter of the adjusting gear (17) corresponds approximately to d <: r width of the guide block (1) and the adjusting pawl (23) opposite the adjusting lever (19) is cranked.