DE1505569A1 - Auxiliary power device, in particular brake amplifier - Google Patents

Description

Utility model application

ROBERT BOSCH QMBH, Stuttgart-W, Breltscheidatraße 4

Auxiliary device, especially brake booster

The Ei'f'ivjung relates to an auxiliary power device, in particular a brake booster for motor vehicles, in which a pole valve operable by means of a control element controls the movement of a force element, and in which the control element and the force element also act on a force transmission element via a force selection device.

In a known brake booster according to US Patent 2,437,721 the control member and the force member (power piston) acting on a plurality of rear active lever, which are supported with its central region on the opposite side to the Kraftube'rtragungsglied (piston rod).

009830/0146 bad O

Robert Boüch GmbH R.-Nr. 860T 569

Stuttgart March 30, 1966 01 / Κθ

The result of unbalanced forces with the help of the levers: 'ffiKfn fblative movements of the control element, the working piston and dev K-ilbeast.QiigH has been conveyed by df- »m Polgevantil, which the generated auxiliary controls. The force equalization device this EiTisve; r; ti Li'k »jf; ί is difficult to determine, which means that the manufacturing

Um ixeät »üu i'U'i '· üij, is boJ. a brake booster according to the German Pal;. ': ri'c3i.lii'i.n 1 193 532 ί-ΐν ^ οΠ * dor Hsbal a Gurnmikürper or a FlUsalgkeibabifiai In eJjie ¹ ^ vom Sfcuuorfrlisd, vom Kraffc ^ lied and vom Kr ^ l'tulv ^ i'Ti '.-'. gun. ^ figlied 1>Ώ:; ι \? η? Λ · ί »η and Vfir'bindlichen Barely an ^ oorders. This unequal force device, which acts according to the hydrostatic flat balance, has bpj. The disadvantage of the rubber body is that finely graduated braking with feel is not guaranteed because the rubber body is always cold at low temperatures. This disadvantage is alleviated with a bladder that is normally filled with volatility, but its permanent stability is limited in the case of strong stress.

To vonneiden this Hachtsile, the power assist device is characterized according to the invention that the control member, dns force member and the KraffeUbertragungsglied obliquely mutually inclined Plliöhen aui ^ ieisen which define a d by mutual Verschiebem ^ r faces variable space in which at least one of Zwlsöhon member adjacent to the three surfaces arranged to be displaceable I. \ t _a

With a ¹ auxiliary power supply with central ita Kraftglled g Steuergliad and cleiühachsig annohlienenaem power over rtraguncsgl-Lk! vreiaen na ^ jii a second Herkrcal dor invention Wf; nigsfeons?, wei .iieser irliedfii ¹¹ zueliianolsr gone Kegelf! Already on, awiso'aen O.cnvn -mn angren '/. önden Plüohe of the third Öli ^ .ss air. Rinn l '^ gt- ü; ¹ r ' ore sliding bait are arranged.

As a particularly advantageous Verechiebegliftder ir · / ϊι ch Direct feature of the invention suitable rigid balls.

BATH ORIGINAL

00983C / 0145 " ^3rd

Robort Bosch OmbH R. No. 8601 Stuttgart March 30, 1966 Ol / Ke

Further features of the invention emerge from the following Description and the drawing. Bs show

1 shows a brake booster in section and FIG. 2 shows a force equalization device of one further Brens amplifier in section.

The brake booster “to which a master cylinder (not shown) is built” has a cylinder pot 1, a cover 2 attached to it, and a working piston 3 that can be displaced in the pot 1. The piston 3 has a central, hollow extension 4 which protrudes through an opening in the deodorant 2. The cavity 5 of the attachment 4, which is open to the outside, is stepped inward by two radial shoulders 6 and 7 and opens into an opening 8 of the piston 3 Breakthrough θ guided control stick tick 11 carries articulated. The end of the control stick 11 facing the actuating rod 10 is designed as a valve 12 and interacts with a valve member 14 which is arranged in the cavity 5 of the attachment 4 and is pressed against the valve seat 12 by a spring 13, which is connected to the valve seat 12 of the control piece 11 and the Shoulder 7 in the approach 4 of the piston 3 forms a sequence valve. . Starting from the annular space between the valve seat 12 and the shoulder 7, a channel 24 leads into the chamber to the right of the piston 3 and, starting from the shoulder 7, another channel I5 into the chamber to the left of the piston J>, into which a connecting piece 16 for a suction line opens.

On the part of the opening 8 opposite the cavity 5 in the extension 4, a cylindrical surface closes via a conical surface 17 Extension 18 in piston 3. In this extension 18 protrudes a piston rod 19 with a flat, widened head 20. The die The piston rod 19 penetrating the chamber to the left of the piston 3 is in the extension 18 with play limited by a snap ring 21 axially movable. The end of the control piece 11 protruding from the opposite side into the extension 18 is shaped into a truncated cone 22 " so that the conical surface 17 of the piston 3, the truncated cone 22 of the control

BAD ORiGSNAL

009830/0145

Robert Bosch OmbH · '**' R. -No. 8601 Stuttgart: March 30, 1966 Ο1 / Κβ

■. ■ ·

Piece 11 and the flat surface 20 * of the head 20 of the! Piston rod " a variable annulus with essentially triangular shapes Include cross section. There are several in this area rigid balls 23, which touch the three surfaces mentioned, on which the control piece 11, the piston 3 and the piston rod 19 are mutually supported when loaded, you perform Radial movements balance forces between the control unit 11 and the piston 3. So that the balls 23 each move radially, they are guided in grooves 23 *, which are located on the conical surface 17 of the Piston 3 are arranged, but also on the head 20 of the piston rod or Tc can be on the truncated cone 22 of the control plug 11.

The path of the control piece 11, which is carried by a sioh on the shoulder 6 In the approach 4 and on a collar 25 on the actuating rod 10 supporting spring 26 is pressed against the valve member 14 »is through a finger 27, which engages an annular groove 28 on the circumference of the control piece 11. A supported on the bottom of the pot 1 back. Guide spring 29 presses piston 3 against cover 2.

The brake booster works as follows1

In the rest position, the sequence valve, whose control valve 11 rests with its valve seat 12 by the force of the spring 26 on the Ventllglled 14, which has been displaced into the drawn right end position, which connected by the connection piece 16 to a vacuum source Oil pressure chamber to the left of piston 3 through channel 15, the valve chamber and channel 24 with the pressure change chamber to the right of piston 3. As a result of the pressure equalization on both sides of piston 3 The FUIc kf clock spring 29 is able to press the piston 3 against the cover 2. The consisting of the balls 23 and the parts adjoining them * Force weighing device is only insignificant due to the piston rod 19 loaded from the master cylinder.

When the brake lever 9 is stepped down, the actuating rod 10 moves the control piece 1] to the left. In doing so, the valve element 14 first rests against the shoulder 7 in the attachment 4. The connection between the two chambers on both sides of the piston J> is thereby interrupted.

ORIGINAL BATHROOM

009830/0145

Robert Bosch GmbH R. No. 8601

Stuttgart, March 30, 1966

When the brake lever 9 is stepped down further, the valve seat is raised 12 of the control piece 11 from the valve member 14, so that air untsr atmos ph äri achein pressure from the hollow raun: 5 of the attachment 4 hear through that Valve member 14 and channel 24 in the Druckwechselkaretner right of the Piston 3 can fit. The pressure difference generated in this way pushes dar Kci.bari 3 like the SteufirstUck 11 over the balls 23 iai working senses on the piston rod 19

During the movement of the control piece 11, which initiates the movement process, the balls 23 are parallel to the conical surface 1? moved the piston 3 resting on the cover 12, displacing the piston rod 19. The subsequent movement of the piston? * 3 now pushes the balls 23 inward again until the control piece 11 and the piston assume a compensatory position in which the auxiliary force and the control force correspond to the counterforce, and with dor Furthermore, the valve member 14 rests on the valve seat 12 of the control piece 11 and the shoulder 7 in a sealing manner. There is therefore no further increase in pressure in the pressure wax karamer.

If the steering force is reduced or removed entirely, so that the Balancing position is disturbed by the force of the piston 3 and the counterforce of the piston rod 19, the balls 23 on the conical surface I? Welter pressed inwards, so that the control piece 11 also with Support of the spring 26 lifts the valve member 14 off the shoulder 7 again. The higher pressure air in the pressure swing chamber "

is then sucked off by the vacuum source through the now re-established connection with the constant pressure chamber, the piston 3 returns to 3elne rest position.

In addition, it is noted that the ratio of the control force to the auxiliary force for the compensation position of the force weighing device can be designed differently if the conical surface on the notches and on the Steueret lick are provided with different angles of incline. The same can be achieved if the third contact surface is also designed to be conical. A progressive ratio of auxiliary power to control power can be achieved if at least one of the with the

009830/0145 -V-

GmbH R. No. 8601

, 30.3.1966 Ol / Ke

Kr: -i'jA: ^^ nmrmlrkenden surfaces are arched .. Instead of the Ki; *; «Wipe the inclined surfaces of the forces

wi:, Uaig of the Bratnseamplifier also double wedges or an im

Ur:; in) her ring, for example a rubber ring or a worm «

f ^ t «ground. An elastic QuintBiring also has the

'■ / -G iisv control path of the control element in its initial part

s: Td ^ so that the control travel-brake pressure curve is progressive.

E *, -li; fß characteristic results in particular »if an ο 'w, ρ ilungring is used. The elastic ring (30) can have at ■ * spiere? Chr.lt t, which is approximated to a triangle,

w ν f.oigt « In this case, as long as the mutual Bc ·" i 'are clear, the cross-sectional size remains approximately the same, so that there is no friction against the contact surfaces. Of the . if as Me is always under compressive stress in all parts and bf A *. , fi- * inen essentially triangular cross-section at what its hold! ai k @ it very favored.

8AD O

009830/0145

Claims (1)

Robert Bosch örcbli Stuttgart Expectations 1. Auxiliary power device, in particular brake booster for motor vehicles, in which one can be actuated by means of a control element Sequence valve controls the movement of a force member, and in which, furthermore, the control member and the force member act on a force transmission member via a force selection device characterized in that the control member (11), the force member (3) lind the Kraftüborti s ^ uigeglied (19) obliquely sue m ^(S, ££ 17 · 20) have surfaces which are a by mutual The push of the area "variable space limit, at least one (*, 22 17 * 20) fitting intermediate member (Sjj) slidably disposed in the at & ~ m three surfaces 1st. 2. Egg lfsv ei --richtung according to claim 1, characterized in that, of the άν, -an-cavity-defining Fläohen (17, 20 *, 22) at least -r ^ _ 'in the form of gleiohachslgen fläohen cone (17, 22) exhibit. 3. Auxiliary device according to claim 2, characterized in that that in per se known catfish In a central Durohbruch (8) of the force element (3) guided control element (ll) bevelled conically and the opening is widened in a conical manner, and that the force-transmitting element is in the widening (18) from the surface (19) protrudes with a flat face. H. KiIfsvorrichtung according to one of claims 1 to 3 # characterized in that at least one of the variable space '4!? Tgcbf »ndf» n surfaces are arched. 009830/0145 b.ad C ^ - Robert Bosch GmbH _ R. -No. 8601 Stuttgart S March 30, 1966 01 / Ke 5. Auxiliary device according to one of claims 1 to 4, characterized in that a plurality of balls (23) in the variable space are arranged. 6. Auxiliary device according to one of claims 1 to 4, characterized in that »that several double wedges are arranged in the variable space. 7. Auxiliary device according to claim 2 or 3, characterized in that that a circumferentially elastic ring is arranged in the space bounded by the conical surfaces. 8. Auxiliary device according to claim 7 »characterized in that the ring has a circular cross-section. 9 «Auxiliary device according to claim 7», characterized in that the ring (20) has an essentially three-dimensional cross-section. 10. Auxiliary device according to claim 7, characterized in that the ring is formed from a worm spring. 11. Auxiliary device according to claim 5, characterized in that the balls (23) in grooves (23 *) of an adjacent Flftohe (17, 20 *, 22) are listed, 009830/0145