Патент USA US2107257код для вставки
Feb. 1, 1938. . ‘c. BEUSCH 'HYDRAULIC BRAKE v ‘ - Filed Sept. 19, 1935 ‘2,101,257 I I I Patented Feb. 1, 1938 , 2,101,257. . UNITED STATES PATENT ' OFFICE 2,107,257 _ HYDRAULIC BRAKE Christian Beusch, Wadenswil, Switzerland Application September ,19, 1935, Serial No. 41,322 5 Claims. (Cl. 188—152) This invention relates to vehicle brakes of the hydraulically actuated type and especially to im provements in parts of the brake system dis closed in my application Serial Number 33,906, 5 ?led July 30, 1935. In said prior application I have disclosed vehicle braking methods and de be the cause, such; variations of pressure must be promptly corrected. vices in which two liquid systems are involved. The primary system is actuated by the operator and serves 'to apply a braking force to one or both 10 brake shoes of one wheel only. The torque gen erated by the braking effect of the one wheel is utilized to operate the second liquid system to apply the brakes on the other wheels and pos sibly one of the brake shoes of the ?rst wheel. 15 ‘The braking effect of the two ?uid systems are so correlated that while the ?rst wheel may be locked, the braking force applied to the other wheels is somewhat-less than that applied to the ?rst wheel whereby the other wheels can not be 20 locked. This is responsible for very favorable results in many respects, only three of which need ' be here mentioned. First, the force necessary to be applied by the operator-is many times less than would be necessary if all the wheels are ' - The problem of maintaining the secondary system full of the braking liquid is somewhat complicated by the fact that the master cylinder 5 or cylinders must be provided with two pistons in order to provide for braking in both directions The present invention has for an object to pro vide a braking arrangement of the kind in_ ques tion which will at all times be properly supplied 10 with ample‘ force transmission ?uid. A further object of this invention is to pro vide a master cylinder or cylinders of the sec ondary liquid circuit of a braking system in which the pistons will consistently returnjto their 15 fully released position whenever the braking force applied thereto ceases. ' ' A_ further object of this invention is to provide the master cylinder of the secondary liquid circuit with‘ means for ensuring an adequate 20 supply of force transmission ?uid. ' Another object of the present invention is-to provide master cylinders for secondary circuits in which the forward and backward braking 26 forces are applied in di?erent chambers. ‘A further object of this invention is to pro 25 braked directly. Second, since only one wheel. may be locked skidding and swerving of the ve vide simple and e?‘icient forms of master cylin hicle is notrcaused to any extent. Third, since ders for vehicle\brak_ing systems and to provide all but one of the wheels are always braking ‘means for ‘maintaining them amply supplied with rolling friction instead of sliding friction with braking ?uid. _ 30 practically the maximum braking effect is ob Further objects and advantages of the inven tion -will be, apparent from the following de As previously stated the braking torque of the tailed descriptipn and drawing of several em-v ?rst wheel is utilized to apply the brakes of the bodiments: representing the. invention. other wheels. This is done by applying the said In the ‘accompanying drawing, Fig. 1 is. a .35 torque force, whether backward or forward, to diagrammatic representation of the type of brak a liquid contained in a master chamber or cyl ing system and apparatus to which the present inder by means of one or the other of a pair relates; . v of pistons according to whether the direction of invention Fig. 2 is a side view partly in section of parts the braking is backward or forward. This pres of the brake applying mechanism of a lcontrol40 sure is transferred from the said master cylinder ling wheel in which one brake shoe is operated tained. " ' _ throughout the entire secondary fluidv system and ls,_utilized at each of the wheels to be braked thereby for applying an equal braking force on 45 each of said wheels. 30 - . Fig. 3 is a side sectional view of one embodi ment of a master cylinder. Fig. '4 is a side sectional view of a second 46 embodiment of a master, cylinder chamber in which the two pistons operate in different com municating cylinders; and will be realized that many factors. tends to cause variation of the pressure in such systems for in separate cylinders. pheric pressure, wear of the moving parts and 55 possible slight leakage, etc. No matter What may 40 by the secondary liquid circuit. Now, it is essential to a satisfactory practical operation of ‘such braking arrangements that both of the liquid circuits, primary andsecond~ ary, shall at all times be entirely full of the braking liquid, but without excessive pressure. It stance variations of temperature and atmos- . 35 Fig. 5 is a side sectional view of a third em-_ bodiment in which the two pistons operate in 50 . In the vehicle braking system, to which the ' ‘present invention relates, two liquid systems 1 and I‘! are provided. The primary‘ liquid system ‘I is directly under the control of the operator l5 2,107,257; who applies pressure to the liquid in system 1 by pressing on pedal- I, which pivots lever 2 to push piston 3 to the right in cylinder 4. This presses the liquid through the primary system pistons into bearing engagement with the outer ends of brake jaws l I. The features of the system of Fig. 2 not shown in the drawing are similar to those of the system of Fig. 1. ‘I into cylinder 9 where it presses pistons l6 apart and brake shoes II are forced into contact, in the secondary systemsiof the above described with an exterior brake drum of a wheel (not shown). Cylinder 4 extends into a liquid con tailner 5, and is provided with a port 6 through 10 which liquid may flow from or to the primary system each time the piston moves to release position, whereby undesired pressure variations in said system are promptly corrected. The pri In order to maintain the proper volume of liquid braking arrangements, in accordance with the present invention the secondary system master ' cylinder is provided with a-liquid supply reser voir and special connections therewith. In Fig. 10 3 a master cylinder for a secondary system is shown in section and is designated generally by numeral 4|. The ends of this cylinder may be ' mary liquid system is therefore always main 15 tained full and free of undesired pressure re turned inwardly as indicated at 42, 43 to provide abutments for pistons or packing members. A 15 gardless of changes in conditions tending to vary liquid reservoir 44 is associated with cylinder 4| its pressure. . 1 and as shown may oe formed integrally there The brake shoesior jaws II are pivoted at ' with if desired.‘ Within the cylinder 41 ‘are ar points l2, l2 on a supporting frame I3 and are ranged a pair of pistonsor plungers 45, 46 nor? resiliently drawn toward each’other by spring mally spaced apart. ‘A compression spring 41 II_'. This frame is mounted on axle 6 and is yieldingly' biases the pistons apart. One of the capable of free rocking movement about the axle pistons, for instance piston 45, is attached to a in either direction. 'lhe cylinder 9 is also rod 50 which extends into one'end of the cylinder mounted on this supportingqframe l3. It .will be and is adapted to receive aworking force on its seen that when the brake shoes I l are moved into outer end from ‘an arm H of the frame l3, braking engagement with the brake drum of. the similarly as the rods of pistons |5 of Figs. 1 and moving wheel a torque will be applied thereto 2. The rod 50 is provided with a second piston and this will be transmitted to frame I3 through 52vspaced from piston 45, whereby a chamber 53 ‘ pivots. l2 and cylinder 3, and frame |3 will there is formed therebetween. Also a third piston or fore tend to rotate-about the axle I in the direc abutment 54 is formed or attached to rod 5|] at a tion of the force applied thereto. I This tendency of frame II to rotate is used . for applying the brakes of the other wheels of- ‘the vehicle and to this endframe I3 is provided with a pair of .spaced extensions H the. inner faces of which engage the ends of operating rods '54, 56 of a pair of pistons or ‘plungers 45, 46 in cylinder 4|. Cylinder 4| is securely mounted on , a fixed part of the vehicle. - The cylinder 4| is the master cylinder of the. secondary liquid system II, that is to say, pres sure exerted on the liquid in cylinder I6 is applied position spaced from piston 52, forming .there between a»chamber_55. , , _ - Piston 46 is attached or formed on the-end of rod 56 which extends outwardly through the op posite end of the cylinder 4| from the rod 56 and 35 is adapted to be engaged at its outerend and operated by the other arm l4 of frame l3, (see Figs. 1 and 2). This rod is provided with a second piston or abutment 53‘ spaced'from piston 46 and forming therebetween a chamber 60. 40 When in non-operative position or when the opposite piston is operative the abutment pistons to brake operating cylinders 2| at each of the 54 and 58 engage the inwardly turned ?anges 42, . other wheels to be braked. -Cylinder4| is con 43 respectively and limit the outward movement nectedwith-each ofthe braking cylinders of the of their associatedarods 56 and 56 respectively. other wheels by conduit system l1 and each of the ‘ The pistons and abutments 54, 52, 45, 46 and 56, cylinders 2| applies or releases the associated which*are ‘slightly'smallerthan the cylinder to pivoted brake shoes 23 in accordance with move allow free sliding therein, are provided on their ments of pistons 22 in said cylinders ‘in response inner face with sealing devices 62, 63, 64, 65 and to the fluid pressure and as‘ in?uenced by tension 66 respectively for preventing undesired passage springs |_|' connecting the various pairs of shoes. of ?uid outwardly toward the ends of the cylin- In the modi?ed construction shown in Fig. 2 der 4|. 7 vofthedrawlng,onlyonelu'akeshoe || is'directly The space between the inner pistons 45 and 46 actuated by the primary liquid circuit. 'The is connected with the‘i'secondary' liquid system I‘! other shoe or thev controlling wheel is op through a ‘port 68. When one or the other of erated by the secondary‘ system. To obtain this the rods 50 or 56 is pushed'inwardly, theother result the cylinder 3 of the ?rst described ar is held against yielding by its abutment engag rangement is substituted by a double cylinder 26 ing a ?ange at the ends of the cylinder and ?xed on the upper part of supporting frame I3. consequently a pressure .is generated in the This cylinder is divided intermedially by a parti chamber 16 between the inner pistons and trans 60 tion‘wall so that in effect, it is two cylinders. mitted to the secondary liquid system H. One of the chambers so provided is connected “ Chamber "I0 is connected with chamber 53 ‘with the primary liquid system through pipe ‘I, ‘through a conduit 1| formed in the wall of and a plunger 23 in said cylinder actuates a brakeshoe ||. The other chamber 23' of cylin der 26 is'connected with the master cylinder l6 of the secondary liquid system through conduit II’. The other brake shoe ll of the controlling wheel is actuated by the pressure of the liquid of 70 the secondary system acting ‘on piston29' in chamber 23". Shoes II are resiliently urged to'ward'each other by interconnecting spring ||_'. The chambers of cylinder 23 may'contain ‘com 7 springs 36, 3| interposed between the partition wall and the pistons for urging the cylinder 4|. One end 12 of this conduit opens ' to chamber 10 closely adjacent piston 46 when in its outer position, whereby a very slight inward movement of -piston 46 seals this'end of the conduit. The other end 12' of the conduit 1| opens into chamber. 52. Chamber 53 also com municates with reservoir “by an opening 15 which opens into chamber 53 close to piston 52 whereby a slight inward movement of piston 52 immediately closes opening 15. It is clear that if either rod 56 or 56 moves inwardly communica tion between reservoir 44 and chamber ‘III is im 75 3 . 2,107,257 ‘ a pair of pistons,one of said pistons being mediately interrupted ‘while upon return to its having located in said cylinder having a forward and a outer position communication is immediately re established. Therefore, each time the brakes are rearward packing ring, and having a ?uid passage ‘released the secondary liquid system is equalized between said rings, a reserve ?uid reservoir con and corrected if necessary to the proper pres sure and volume and will at all times be auto-_ said rearward-packing ring, and aconduit'con nected with said ?uid passage closely adjacent matically kept at the proper pressure. The reservoir 44 may be ?lled from time to time nectin'g the passage between said rings with a point in the chamber closely adjacent and in ' front of the other piston, said other piston having through opening 16 closed by stopper 11. a ' packing ring, whereby the initial part of a 10 In the embodiment of the invention illustrated 10 brake applying movement of either of said pistons in Fig. 4 the principle of operation is quite similar to that of Fig. 3. However the two pistons are disposed in different cylinders 4|’, 4|" com ' municating with each other at their inner ends seals the master chamber from the reservoir, and communication between said chamber and reser voir is established each time both pistons move to release position. X but having their ‘axes angularly disposed with full 2. A master chamber for hydraulic brake sys respect to each other. In thiscase a pairof > tems for vehicle wheel brakes,'comprising a cylin compression springs 41’ are provided and their inner‘ ends, opposite the pistons, abut against der, oppositely facing pistons in said cylinder, said cylinder and pistons de?ning a control space of abutments 80, 8|. The two cylinders are in com variable capacity, according .to the positions of 20 20 munication with each other, when the brakes the pistons, means for positively limiting move are released, by means of a conduit ‘H’ formed in the-cylinder casing, and opening into cylinder ment of each of said pistons in said cylinder in the directions which expand the control space, 4|’ at a point immediately in rear of its inner most piston 45’, and into cylinder ll" at a point means connecting the hydraulic system with said 21', control space, means for moving one or the other 25 immediately in front of its innermost piston. The reservoir 44' may be formed separately from of said pistons in a direction/to reduce the capac of said control space depending on the direc.- . the cylinders and communicate therewith by ity conduit 15' opening into cylinder 4| at a point tion of braking of the vehicle, and pressure between pistons 45'- and 52’. End sealing and equalizing and adjusting means for said control space a. id system comprising a braking ?uid 30 abutment engaging pistons 54' and 58’ are pro reservoir, conduits connecting the reservoir with vided in this embodiment also, and engage abut the control space when both of said pistons are ments 42' and 43'. This embodiment is other wise similar to that of Fig. 3 and further descrip-" in the position of maximum expansion of°the 15 ‘control space and means for interrupting communication between said reservoir and control space when either of said pistons is in a position a pair of separate cylinders and reversed pistons. reducing the capacity of said control space; . 3. A master vcylinder for hydraulic brakes for The working chambers 10' and 10" of the cylin ders483, 84 respectively are at the outer ends of ‘ vehicle wheels comprising a. cylinder, a rod ex the cylinders and are in communication through tending into one end of said cylinder, and having 40 40. conduit 85. This conduit 85 is in connection with three spaced pistons each provided with a sealing a secondary braking system 86 corresponding to ring engaging the inner wall of said cylinder, the system I‘! of Fig. 1_ or H’ of Fig. 2. The inner spme between the inner and intermediate sealing ends of the cylinders are provided with inwardly rings constituting a ?uid passage, a second rod extending abutment ?anges ,42‘”, 43", against extending into said cylinder from the opposite 45 which abutment pistons 54", 58" respectively end from the ?rst rod, said second rod having may engage. In this embodiment the rods 50', two pistons each provided with a sealing ring 56' extend toward each other into or substan - engaging the inner surface of the cylinder, means tially into engagement with an arm 90 of a frame to limit the outward movement of said rods, a 9| pivotally attached to the axle of the vehicle ?uid supply and equalization reservoir, a conduit and in?uenced by braking torque of a controlling connecting said reservoir with said cylinder at a ‘ .point adjacent the passage between the inner wheel similarly as frame [3 of ‘Figs. 1 and 2. In stead of apair of arms It as on frame l3, only and intermediate sealing rings of the first rod a singlearm 90 need be provided on the frame 9|. and. closely adjacent the ‘intermediate ring, the Chamber ‘l0’ communicates with chamber 53' wall of said cylinder having a passage extending by means of a conduit 1 l” which opens into these from said mentioned passage to a point adjacent ‘ tion therefore‘appears unnecessary. - ' The embodiment shown in Fig. 5 is also similar 35 in principle to‘ that of Fig. 3, but is provided with chambers at points corresponding to the quivalent points in chambers 10 and 53 of Fig. 3 and'for the inner side of the sealing ring'ofthe inner piston of the other rod, means yleldingly pressing the rods toward their outermost positions, and a the same purpose. 'Chainber 53' also communi cates with a reservoir 44" through port 15" when ' hydraulic system connected with said cylinder at 60 non-operative. ' It will be apparent that the connections and "1 principles of operation of each of the above de scribed embodiments are similar, and that in each case the secondary liquid system is put into com munication with the pressure and volume equaliz ing reservoir each time the brakes are fully re leased.- However, immediately upon operation of a point intermediate the two inner pistons. 4. A master cylinder for hydraulic brakes for vehicle wheels comprising a casing provided with a pair of cylindrical openings angularly disposed with respect to each other directed toward each other. and communicating at their inner ends, a rod extending into one of 'said openings, said rod having three spaced pistons each provided with a ?uid sealing ring engaging the inner wall , I the mechanism in either direction the reservoir of the opening in which they are located, the is tightly closed off from the system so that no ‘space between the inner and intermediate-seal leakage thereto can occur. The system is thereby .ing rings constituting a?uid passage, a second maintained in proper working order at all times. rod extending into the other cylindrical opening, I claim:- . I ‘ 1. A master chamber for- vehicle wheel hy draulic brake actuation comprising a cylinder. said second rod having two pistons each provided with a ‘sealing ring engaging the inner surface of 4 ' 2,107,257 the opening in which they are located, the outer abuts to limit the outward movement of said rod, ‘ends of said openings extending inwardly, the ‘ the other end of said ?rst cylinder being closed, outermost pistons on each of said rods engag ing said inward extensions and limiting the out ward movement of said rods, a ?uid supply and equalization reservoir, a conduit connecting said reservoir with the ?rst mentioned cylindrical opening at a point adjacentv the passage between the inner and intermediate sealing rings _of the 10' ?rst rod and closely-‘adjacent said intermediate ring, said casing having a passage extending from said ?rst mentioned passage to the second a ‘second rod extending into the second cylinder from the direction of the ?rst cylinder, said second rod having two spaced pistons thereon within the second cylinder, each 01 said pistons \ having a ?uid sealing ring engaging the inner surface of said secondcylinder, the end of said second cylinder entered- by said second rod hav ing astop against which the outermost of said two'pistons engages to limit the outward move ment of said second rod, the other end‘ of, said second cylinder being closed, a conduiticonnect ing the opposite ends of said cylinders with each other rod, means yieldingly pressing the rods to other and with a hydraulic brakesystem, means vward their outermost positions, and a hydraulic , for supplying Land equalizing ?uid in said system, opening at a point closely adjacent the inner side of the sealing ring of the inner piston of the is system connected with said casing at a. point in termediate the two inner pistons. 5. In a. master hydraulic pressure chamber for controlling vehicle wheel brakes, a pair of aligned cylinders spaced‘ apart. one of said cylinders hav ing a rod extending thereon from the direction of the other cylinder, said rod having three spaced “pistons disposed thereon each of which is pro vided with a ?uid sealing ring, the space between the inner and intermediate sealing rings con stituting a ?uid passage, the end of said cylinder toward the other cylinder having an inwardly ex tending ?ange against which the outer' piston said means comprising a reserve ?uid reservoir, a conduit connecting said reservoir with the chamber between the inner and intermediate pistons of the ?rst cylinder at a point closely adjacent the sealing ring- of the intermediate pistonyand a‘ conduit connecting the said cham ber with the second cylinder at a point in front of and closely adjacent the sealing ring of the inner piston thereof, and means disposed between 25 the adjacent ends of said rods for actuating one or the other thereof according to the direction of‘ a braking e?‘ect. ’ CHRISTIAN BEUSCH.