DE1453475A1 - Valve for the automatic control of piston pumps, especially radial piston pumps - Google Patents

Description

JOHN DEERE - LANi -j / c ο / η c public company

(aeo)

Yemtil sum selbettatigen rules τοη JColbenpuapen, in particular Radial piston pump *

91 · Invention looks at "loh auf tin Tentil" to be automatic Rules rom piston pumps, especially radial piston pumps «because» • TA valve housing with rom pressure medium against a spring force beaufaohlagt »organ, furthermore in a Tom Druokraum • na crankraam aar pump leading circuit switched on lat, at then a Terbramoher is aneohlleibar. Slide with the discovery gaganatand The resolving task is seen in ainar improvement daa Temtila, because dia balm Eagaln the pump occurring in addition to pressure · piteen are rermieden, and daa Taatil only required in the smallest possible building space.

lur BagaXung · Χλ% χ BidlalkoXbanpumpa lat achon TorgeacnXagan, since £ Ib Oahäuaa daa Ragal / rantlla a through a radar balaata « \ · ν piston in the bottom position is pressed against a Yentilsit *. Since · τοη dar Pump · promoted · Druoköl presses on dia against dan Tentilsits checked · Front side daa KoXbana and have dlaaan after Brreiohan daa alngaatelltan printed antgagan the force of the spring. Daa Druoköl arrives after Uaotrömen the Sitsfläohe through transverse holes in an axially blind hole machined in the piston, τοη because aua ea duroh a line to daa Ventllgehäux angaachloaaan · line that lurbelraua the pump is lead. The use of the Tentil, since a valve tested against a Yentileits has a drainage device, has disadvantageous features in such valves for hydraulic systems daa geaast · τοη the pump · delivered oil ■ ohlagartlg fills the crankcase la Puapengehaua ·. As a result, the pump pistons are lifted off the high speed of the drive acaanter, the pressure on the other side relaxes and falls under the ingested work.

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the Ιοί ben τοπ the tensioned Tentilfedar with very high speed on a site »is thrown back. 1 «kick so when using tint! Solohen Tentils in dar hydrauliechen Anlage · very cancels Sruekspitsen, dia aret allemehlioh ptriodieoh fade away. Apart from τοη dan strong mechanical ba * anapruchungen dta Tentile, which ei oh also known in dta "flutter" effects]! » the entire hydraulic system is subjected to high pressure surges, which can lead to damage. Another disadvantage of this valve is that the Pressure oil the entire face applied to the high pressure side of the Yereohlu organ acts · Pie from the surface of this Face and the pressure resulting pressure force is accordingly relatively large, so that the pressure against this pressure force » Acting spring must be made correspondingly large · The tantile therefore claims an unnecessarily large egg aureum, which is on ü has an unfavorable effect on the entire system

According to the invention, you mentioned head parts are essentially by means of a displaceable piston Termieden provided with a Roman pump pressure acted upon by an axial back bore, operated by the smu dae pressure medium, among other large ones, by the Creislamf swlsehea Sruöfcraiua and Eurbslreum of the pump üca Kolbüma nacheänsnd «r sciaieSend® transverse bores in ibgesfcuftei quantities flow off, whereby the smallest overbore in the office knife becomes effective "Sa b®lm Terschieben the piston is first turned on a relatively small luerbchrung in dtn cycle" is the & narrow, rich at the start of the scheme in the crank space st & rt _v relatively low, eo tHe are now gradually lifted the pump pistons from intriebsezeenter · Deaensspreoksnd is the increase in pressure in the hydraulic system above the set value is relatively low. Said less oil drains off through the small cross-hole than the valve "ustrSmt", a pressure builds up in it,

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U53475

Aer cine further displacement of the piston! »« Works. It will the large · cross hole in dta. Circuit switched on, through correspondingly more pressure ul can flow off. So oil will in graduated quantities the crankcase 'supplied to the Puape' whereby the smallest amount of oil is dispensed at the beginning of the normal process. You have relatively small pressure swings at the beginning of the regulation Auesohlftgc and commute within a short time to the set Setpoint on · By using a blind hole to which the delivery pressure is applied, this pressure only acts on part of the entire cross-sectional flow of the piston. The compressive force is therefore relatively small, so AsJ Ais compression spring can be kept small. Therefore the valve housing can also be dimensioned correspondingly smaller are »so that the entire valve has a compact design.

Iaeh a further suggestion of the invention engages in this open smdo of the saok bore a fixed boIeen, tenon or the like. one on which the piston is slidably guided. In this way, the piston and the pin guided in it also form Relatively low costs do manufacturing files that are also easy to assemble.

read the arrangement of the different diameter cross-bores for the draining oil is concerned, so sees the lrfindung also before that these are incorporated into the piston and open into Ais Saokbohrung, as well as when moving Ae. KoI-bene with a bucket provided in the valve housing, with the drainage pipe connected annular chamber can be brought into connection one after the other. This main assumption is simple and relatively cheap Means Aurehsuftthren.

Another inventive feature is seen in the fact that the Piston is loaded by a compression spring, the tension of which is gradual

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ORKaINAL

lot or in steps. The infinitely variable graduation can result in the regulation on the most favorable value for the plant can be set. let this value be determined eixunal so can

■ in
he valves manufactured in series production step by step _y, for example, the raw insertion of washers, wiping the leather and a fixed screw are obtained. This measure is cheap and affects the manufacturing costs of the valve gate part.

33 solben can according to a further proposal of the invention have an axial through-hole connecting the valve chambers located on its two end faces with one another. That has the advantage that the aforementioned into the free end of the blind hole of the solenoids engaging bolt only with a normal one This need to be processed, i.e. the painstaking process can be omitted 'because that is reflected in the Solaen iu ~ facing face of the piston, accumulating pressure medium flows through the axial bore of the piston.

The invention also provides that the valve via a pressure line and a control line and a main control valve of this type is connectable with the consumer that it is after his holding acts as a pressure relief valve · This way can on an overpressure valve between the pump and the consumer must be provided is the same in the servo heater and in the control valve, that is Hydraulic system by this also from the consumer side against overloads, pressure systems and similar harmful Secured against influences.

Details of the invention are from the description below and the drawing can be seen, which illustrates two exemplary embodiments of the subject matter of the invention. It shows

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6AD OTOGINAL

lig · 1 the first exemplary embodiment of the invention Regularly profitable bit stepless pressure setting and one automatically controlled by this. Pump cut while the lines and other hydraulic ropes schematically are shown,

fig. 2 part of the second version of the sailing valve '' for gradual pressure adjustment in the cut.

In fig. 1 of the drawing, P denotes a pump consisting of a Container 1 sucks in a medium, for example hydraulic oil, via a suction line 2. The pump P consists of the pump housing; the Yentildeekel 4 and the Druckdeokel 5. The files 3 to 5 are held together for example by means of countersunk Allen screws 6 · In the pump housing 3, radially arranged pistons 7 are slidably guided in bores 8. The pistons 7 are pressed by compression springs 9 against the outer ring of a Hadellager 12 seated on an eccentric 10 of a pump shaft 11. The other end of each compression spring 9 is supported against the inner end of an unscrewed screw 13. In the Yentildeokel 4 are Suction and pressure rents 14 and 15 housed. The suction valves 14 are angeord between the bores 8 and a suction chamber 16 net, while the pressure valves 15 in the connection path between the bores 8 and a pressure chamber 17 are built in · The storage the pump shaft 12 is carried out by needle bearings 18 and 19 » one of which is housed in the housing 3, the other in the yentil cover 4

The eccentric 10 rotates in a provided in the housing 3 Crank chamber 20, which has a throttle «! with the suction chamber 16 in

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6AD ORIGINAL

Connection. Hlerxu let in the valve cup 4 «la · threaded hole 21 provided, which opens into the bearing 19 for the inner journal of the Puapenwelle 12 receiving bore, A threaded plug 22 is screwed into the bore 21, the one with a Droseel hole running in its longitudinal axis 23 is provided. The crank chamber 20 is therefore connected to the intake chamber 16 via the bore 23 *

A pressure bore 24 opens into the pressure space 17 "connected to the" pressure line 25. The pressure line 25 leads to a main control valve 26 with which, for example, a single-acting working cylinder 27 can be actuated. The control valve 26 is connected to the container 1 by means of a return oil line 28. The oil displaced from the cylinder 27 when the animal load is lowered flows through this line into the container 1 surüek. A control line 29, which is connected to a control valve R at the other end, is connected to the pressure line 25.

The control valve E comprises a valve housing 3Q ₉ which is provided with a through XiSaagßbohrung 3t. One end of this bore 31 is closed by a screw 32 so that it is impermeable to liquid. In the GeMuae 30 there are two annular chambers 35 and 34 arranged at an axial distance from one another, the other of which is connected to the control line 29. The second actuator 34 is connected via a line 35 to the crank chamber 20 of the pump P aageschlöBeen _f in which the eccentric 10 actuating the piston 7 rotates.

In the bore 31 an asylindri shear piston 56 is slidable out, which is loaded by a compression spring 37 1st. The piston 36, in turn, has a one running in its longitudinal axis Blind hole 33 is provided into which a fitting bolt 39 is inserted, which partially fills this hole. The piston 36 is doing itself

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_ ₇ _ U53475

in the closed position by means of the pass bolt 39 against dl drilling hood 32. Zn the piston 36 are cross holes 40,

41 and 42 incorporated, which open into dl · blind bore 38. Di · borehole 40 let for the inlet rorgeeehen and eteht old dtr Annular chamber 33 in constant communication. The holes 41 and

42 are located approximately mm at the end of the blind bore 38 and can by displacement of the piston 36 old of the bing chamber 34 in connection be brewed. The bottom of the hole 33 For example, the Kajmer 34 “cross-hole 4I, which is located at the opposite end, has“ wok- ■ äflig a relatively small diameter. Xn the surrounding area · de » Piston 36 let an annular groove 43 with a triangular cross-section incorporated, dl · has a connection with the larger bore 42. Through this a pressure equalization is achieved on the entire circumference of the piston 36, so that it does not get stuck. By means of a to the Saukbohrung 38 parallel Durohgangsbohrung 44 can swisohen in the tree The Leok oil which has penetrated the piston 36 and the screw 32 is diverted so that no pressure builds up in this tree can · The Leoköl flows through a bore 45 and one to this connected · ^ corner oil line 46 In the BiliäXt ** 1 from bsw. right away back into the suction chamber 16 of the pump «

For the exemplary embodiment according to I ¹ Ig. 1, the tension of the pressure plate 37 can be continuously adjusted. For this purpose, the spring 37 is supported against a twisted Peder plate 47, which on the one hand rests against an adjusting screw 48. The screw 48 is screwed into a hollow screw 49, which in turn is turned into the other end of the valve housing 30. The adjusting screw 48 is through a lock nut 50 to prevent unintentional twisting.

In the exemplary embodiment according to Fi £. 2 can be the pressure, the one Displacement of the piston 36 causes a gradual adjustment of the tension of the compression spring 37 to be selected. Tue Compression spring 37 is here against one on its inner 2nd

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U53475- -β-

Unscrewed screw 51 which is screwed into the valve housing 30 iat. By inserting pads 52, the tension of each 37 and thus the release pressure is increased. This version iat advantageous for series production, since the manufacturer einaal determined the most favorable pressure with the washers 52 can be set

The Hegelventila R works as follows *

The oil sucked in from the container 1 by the pump P is fed to the main control valve 26 through the pressure line 25. Let the control valve 26 be brought into the "lift ¹¹ " position, the pressure oil flows into the cylinder 27 and the permissible control valve Έ · Haeh The oil that is still delivered by the pump P can now pass into the crank chamber 20 of the pump P via the control valve.

If the main control valve 26 is set to "Heutral", the inflow is off Sum working cylinder 27 is locked. The pressure oil gets through the pressure line 25, the control line 29, the hanging chamber 33 and the transverse bore 40 in the blind bore 38 of the piston »36 · Since there is no drainage free for the oil at first, there is bout itself in the Blind hole 38 exerts a pressure on the one hand on the shift-Iich mounted piston 36, on the other hand on the passport sleeve 39 acts »Since the pressure oil is introduced into the bore, '38 a relatively small area is applied to you, the one from the The cross-sectional area and the compressive force resulting from the pressure are proportionate small. The spring counteracting this force can therefore also be made small. Once the Pressure in the hole 38 the set tension of the leather exceeds the piston 36 with respect to Tig. 1 of the drawing verscnoben to the left, while the slide in the bore 38 guided fitting bolts 39 are shown in the drawing

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BATH

position is maintained by the displacement of the piston 36 Sunäohst the relatively small transverse bore 41 «it the Bingkamaer As a result, the oil flows through line 35 into the crank chamber 20 and here presses on the pump pistons 7, which thereby τοη of the Si «enter 10 are lifted somewhat. hit Withdrawing pressure, the piston 36 is pushed further to the left, until the larger bore 42 with the ring camera 34 The pump pistons 7 are still connected rom Sxsenter 10 lifted off, so that the hub and thus the JÖrder « quantity will be relatively small, while the pulley shaft 12 continues to run with an unchanged turning tool. That sioh in the crankcase 20 accumulating Druokül can fly off through the throttle bore 23 into the anaaugraum 16.

If the control valve is brought out of the neutral division, then The workBiylinder 27 is acted upon with Druokül. Included the pressure drops instantly, so that the piston 36 and the pump piston 7 decrease in accordance with the load. The im Oil that is present in the crank chamber 20 flows into the suction chamber 16, so that the oil in turn, the full hub sur is available. If the control valve acts as a pressure relief valve, the mode of operation is the same.

By means of the adjusting screw 48, the tension of the spring 37 and so that the Druok, which lifts the pump piston 7 from the eccentric 10, can be adjusted continuously. Once the most favorable holding pressure for such a system has been determined, this can be done at Devices manufactured in series production can be optimally adjusted by means of disks 52.

The main control valve 26 can be adjusted quickly or slowly as desired without any disadvantages for the hydraulic system. The use of a piston to regulate the pump creates a smooth control received. Which occur in the known valves with valve seat ' The tendency for high pressure peaks to be reduced »This in turn

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the "flat tear" is prevented as the piston moves quickly settles into a steady state "

The one controlled by the control valve R in the example Radial piston pump P is only a preferred example of application sur control of a pump. The control valve R can also be used to regulate any other piston pump, which one has closed piston chamber, for example an axial piston pump.

claims -11-

909808/0401 BATHROOM CHiQINAL

Claims (7)

U53475 -11- Claims Valve sum automatic control of piston pumps, in particular Radial piston pumps, which have a valve housing with an organ acted upon by the pressure medium against a spring force, is also switched into a circuit leading from the pressure chamber to the crank chamber of the pump, to which a Consumers are available, identified by one with an axial one acted upon by the full pump pressure Saokbohrung (38) provided, displaceable piston (36), from which the pressure medium duroh unterohiedlioh large, the Circuit between pressure chamber (17) and crank chamber (20) of the When the piston is moved, the pump (P) sequentially closes transverse bores (41 and 42) drains in graduated quantities, the smallest cross-hole (41) in diameter is extremely effective. 2. Valve naoh claim 1, characterized in that in the open loading the Saokbohrung (38) a bolt (39), pin or the like engages, on which the piston (36) is slidably guided 3. Valve naoh claim 1, daduroh gekennseichnet that the different Durohmesser having transverse bores (41 and 42) are incorporated into the piston (36) and into the Saokbohrung (38) open out and, when the piston is moved, with a drain line provided in the valve housing (30) (35) connected Rirgkammer (34) can be brought into communication one after the other. 4. Valve according to one or more of the preceding claims, It is also known that the piston (36) is loaded by a compression spring (37), the tension of which is stepless or variable Levels is adjustable. -12- 909806/0401 H53475 5. Valve according to one or more of the preceding claims, characterized in that for pressure equalization at least one transverse bore (42) in one on the outer circumference of the piston (36) provided, for example triangular in cross section, the annular groove (43) opens. 6 valve according to one or more of the preceding claims, characterized in that the piston (36) joins the valve spaces located on its two end faces has connecting axial through bore (44) 7. Valve according to one or more of the preceding claims, characterized in that it is via a pressure line (25) and a control line (29) and a main control valve (26) can be connected to the consumer (27) in such a way that it whose connection acts as a pressure relief valve. 909806 / (HOI