DE2103789B2 - PRESSURE-DEPENDENT ACCUMULATOR CHARGING VALVE FOR HYDRAULIC SYSTEMS - Google Patents

Description

maximum accumulator pressure in the unpressurized return.

Reverse the course to relieve the pressure generator. like the larger piston within a chamber

3 4

arranged, which via a compensation line with the pressure, the seat valve 9, the passage to the memory return connected is. This common piston line 5 releases into the storage container 4. Same- and spring chamber means that the pressure medium is also in the return line the housing or the double piston 10, which, however, by the springs 22, 23 receiving seat valve 12, 13, which is advantageous from a manufacturing point of view, is acted upon by the rest of the seat valve

housing bore. Return line 11 is shut off. In addition,

Embodiments of the invention look up the increasing accumulator pressure over the explained in more detail below with reference to the drawing. It branch 19 shows the smaller piston 16 of the piston or valve arrangement 13, 16, 17 against the force

1 shows a section through an accumulator charging valve io of the springs 22, 23.

a motor vehicle brake system, determined by the springs 22, 23 maximum

F i g. 2 a section along the line H-II of the accumulator pressure, the piston force of the piston is sufficient

Accumulator charging valve according to FIGS. 1 and 16 in order to bias the springs 22, 23

F i g. 3 overcome a section through a modified one. So that the piston assembly 16,

Embodiment of the accumulator charging valve. 15 17 shifted slightly to the right so that the

The accumulator charging valve according to FIGS. 1 and 2 has valve 12, 13 that opens and the return line 10, 11

one to a pump 1 and to a delivery line 2 initially partially releases. Applied at the same time

connected pump connection 3, one with a pressure medium flowing into the return line 11

Storage container 4 and with a storage line 5, the valve member 13 in the opening direction and causes

related memory connection 6 and 20 its further opening.

one connected to a return tank 7. The pressure medium flows into the return line return connection 8 on. device 11 bypassing the pressure retention valve

The delivery line 2 is throttled by a spring-loaded 14 via the throttle bore 15 or at and seat valve 9 acted upon by the pump pressure, exemplary embodiment according to FIG. 3 via the throttle of the storage line 5 separated and is with 25 valve 25 and the bore 24 directly in the back one Return line 10, 11 in connection, in the flow connection 8. This throttled return causes one that releases the return to the container 7 or one determined by the pressure holding valve 14 blocking seat valve is arranged, which results from an increase in the return pressure in the return line valve seat 12 fixed to the housing and a piston-like 11, which both has the piston-like valve-valve member 13 exists. The return line 11 is 30 member 13 of the seat valve 12, 13 as well as via that of on the one hand via a spring-loaded pressure retaining line 21 branching off the return line 11 valve 14 with the return port 8 connectable piston 17 of the piston assembly 16, 17 in the opening and on the other hand, acted upon via a throttle bore 15 directly in the direction of the valve member 13, so that the connected to the return port 8. The valve seat valve 12, 13 by the spring force of the springs Member 13 of the seat valve 12, 13 is coaxial with a 35 22, 23 overcompensating piston force consisting of two pistons 16 and 17 piston-piston assembly 16, 17 in the open position arrangement firmly connected and actuated by this. will hold. That on the piston assembly 16, 17 The smaller piston 16 of the piston assembly's effective ratio of forces also changes then associated with a pressure chamber 18, which has one of not, if for some reason on the storage line 5 branching line 19 from 40 return port 8 an excessive return pressure Accumulator pressure or retention pressure should adjust, since this pressure is at the same time over the larger piston 17 a pressure chamber 20 pulling compensation line 27 in force of the springs 22, 23 is arranged, which branches off the piston arrangement 16, 17 via a supporting line from the return line 11 Line 21 of one below would be sam.

45 Since the accumulator-side seat valve 9 has an un-

is whippable. wanted to prevent the pressure medium from flowing back, sinks

The piston arrangement 16, 17 is also under the accumulator pressure normally only through the action of two or the shut-off pressure or the driving of consumers or the like.
Maximum storage pressure of the storage container 4 When the storage pressure is reduced, the determining springs 22, 23, which the return pressure, or retention pressure, maintained by the 5 ° in the line 21 continue to counteract the large piston 17 of the piston arrangement piston force of the piston arrangement 16, 17 as well as the piston area of the valve member and its preload can be changed. The springs 13, namely until the smaller pistons 22, 23 are arranged within a receiving chamber 26 which also acts on the piston 17 16 of the piston arrangement 16, 17 and which has dropped to a value via a storage pressure, the equalizing line 27 with the return connection 8 is below the shutdown connection releasing the return. The piston arrangement 16, 17 is under pressure, so that the spring force of the springs 22, together with the valve member 13, triple 23 the counteracting piston force of the piston is sealed in the housing of the accumulator charging valve. arrangement 16, 17 or 13 overcomes and the seat in F i g. 3, the accumulator charging valve is slightly 60 valve 12, 13, the return 10, 11 shut off. In this way modified by the fact that the pump 1 conveys the return connection 8 back into the memory 4.
connected throttle bore 15 is replaced by a The level of the throttle-free channel, which is arranged in the same way in relation to the cut-off pressure, is essentially 24 and a spring-loaded throttle valve 25 is determined by the

The mode of operation of the described accumulator retaining valve 14 with the throttle bore 15 or

loading valve is as follows: When the accumulator is depressurized, the retaining pressure generated by the throttle valve 25

container 4 pumps the pump 1 into the delivery line 2, or return pressure and the pressure

so that when a certain opening stroke is reached, the effective piston area of the piston 17 and

of the valve member 13 in relation to the effective piston area of the acted upon by the accumulator pressure Piston 16.

The switching margin achieved in this way prevents the pump from running even if the accumulator pressure is reduced even slightly is burdened by storage charging.

In addition, the seat valve 9 which closes off the storage line prevents the seat valve 9 from acting against the pressure chamber 18 sealed piston assembly 16, 17 a creeping pressure loss of the storage container 4, whereby the switch-on or Load duration of the pump 1 is reduced.

1 sheet of drawings

Claims (3)

ρ,. + _ ·.) .. With the German patent application A 3706 l-atentansprucne. (announced on September 23, 1954) is an 1. Pressure-dependent accumulator charging valve for direction according to the above-mentioned type known hydraulic systems, which have become a delivery line, in which by means of a in the return a storage tank connects as long as its pressure 5 line is a higher cut-off pressure and a lower one by below a certain cut-off pressure, and then connects with a return, connection pressure reaches a defined switching range until the pressure of the accumulator is to be increased to one, and the accumulator connection valve is correct, is below the cut-off pressure and has a return valve whose sealing cone connection pressure drops, with an accumulator connection - coaxial one behind the other by a common valve and a connecting rod releasing the return flow are rigidly connected to each other or blocking valve member, which is dependent on and their moving parts, such as spring, bushing from the accumulator pressure and one in the return flow and piston engied, nested and wired, connected restraint - mechanically mutually influencing arranged pressure in cooperation with one of the 15 are. Such a design results in a spring arrangement that determines the switch-off pressure and the external dimensions of the accumulator charging valve, but it is controllable; Jamming and a larger one, the restraint pressure equations of the moving parts in question,
sensibly acted upon piston (17) existing The invention is based on the object, the double piston, which at the same time the return valve accumulator loading valve so that a forward member (13) carries, which is reached in the opening direction of the given switching range with certainty and is acted upon in retention pressure , as well as in any case is maintained with great accuracy, probably by the accumulator connection valve (9) as well as 25 with the aim of the double piston (16, 17) or the return flow duty cycle or loading time of the pressure valve related to the accumulator filling Keep the valve member (13) mechanically separated pressure generator as short as possible in order to avoid an excessively strong retaining valve (14). Heating of the pressure medium and thus the 2. Accumulator charging valve according to claim 1, avoid the entire system. characterized in that a return flow 30 This object is achieved according to the invention by Throttle bore (15) or one from the double piston one from a smaller one, against the spring force (16, 17) path-controlled spring-loaded throttle piston acted upon by the accumulator pressure and valve (25) is provided, which throttle bore is a larger, the same direction from the restraint pressure (15) or which throttle valve (25) the flow-loaded piston has double piston, moderately the pressure-retaining valve (14) on which at the same time carries the return valve member, which The return line (11) pointing in parallel is acted upon by the retention pressure in the opening direction is switched. is, as well as one from the accumulator connection valve as 3. Accumulator charging valve according to claim 1, also from the double piston or from the return valve through characterized in that the spring arrangement is a mechanically separated pressure retaining valve. (22, 23) and the piston (17) within a 40 This design of the accumulator charging valve has the Chamber (26) are arranged, which has an advantage that the individual valve members for the Compensating line (27) with the return (7) storage, return and retention function or connected is. Piston links controlled exclusively as a function of pressure are or cooperate, while the mutual 45 mechanical influence is switched off. Dar- in addition, allows the design and arrangement of the double piston and with this one Unit forming return valve or the assigned The invention relates to a pressure-dependent receiving bore in the housing, a single accumulator loading valve for hydraulic systems, 50-fold and precise production of these parts, which connects a delivery line with an accumulator if it is necessary for proper operation. as long as its pressure is below a certain cut-off pressure achieved by the operational safety achieved in this way, and then the storage charging valve according to the invention is connected to a return flow until the pressure of the storage tank is particularly suitable for systems that are particularly high, below the cut-off pressure lying supply 55 safety requirements are made, such as switching pressure drops, with an accumulator connection valve, for example vehicle brake systems,
According to an advantageous embodiment of the earth valve member, which, depending on the memory, is a return throttle bore or a pressure and a spring-loaded, switched-on retaining pressure formed in the return line and controlled away by the double piston, in cooperation 60 throttle valve provided which throttle bore with a spring valve which determines the cut-off pressure or which throttle valve is capable of flowing which the arrangement can be controlled. Pressure retaining valve having return line Valves of the type mentioned are connected in parallel, for example. This way becomes a wisely used in motor vehicle braking systems where even restraint pressure is generated or during the pressure medium flow that fluctuates over the duration of the pressure medium return flow from a pressure generator when reaching a predetermined freely maintained.