DE2921359A1 - METHOD AND DEVICE FOR SUPPLYING A CONSUMER WITH PRESSURE FLUID - Google Patents

Description

2921359 Dr. HATE ■ Dr. FRANKE - Dr. ULLRICH

PATENT LAWYERS IN MDNCHEN AND HEIDELBERG

94/444 - ^ - May 25, 1979

Br. P / P Miinohen

SROCE XQUIFMENT COHPiHT Crystal Lake, Illinois 6OOI4, V.St.A.

Method and device for supplying a consumer with pressurized fluid

The invention relates generally to hydraulic pumps, and it relates more specifically to hydraulic pumps for generating hydraulically developed forces for pressure-operated presses, Dies or punches, with the help of which, for example, press fittings can be attached to electrical conductors of various types, wires or cables cut off and have other work of a similar nature carried out. These pumps can be used depending on the requirements of the particular application be set up for manual or foot operation.

Portable hydraulic presses are known per se. For example is in the TJS-PS 2 815 646 a hydraulic compression tool with a main pump described, which is operated by pivoting two hand levers towards each other and away from each other to pluid under high To pump pressure to a master cylinder, which moves a movable press jaw onto a fixed press baoke and so high pressure forces generated in between. In addition, an auxiliary pump is provided for a faster initial advance of the movable press baoke in the direction of to facilitate the fixed press baoke with low pressure. Pure The operation of this low pressure pump requires a twist of the one the two hand levers to obtain a forward or a backward movement of the movable press jaw. Pressure eyes of this kind are heavy, and they are often used in positions with calibration in which the operator of the tool in an uncomfortable or uncomfortable way Must hold position so that devices that require turning a hand lever by hand both for the initial ßohließen of the dies around a work-

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piece as well as the opening of the die after the application of pressure , are tiring in operation. An automatic transition from rapid feed at low pressure to high pressure operation without the need to turn a hand lever is very desirable, especially in such and similar applications. Furthermore, it is also desirable that the operator does not have to turn a hand lever by hand after completing the chucking work in order to retract the movable press jaw so that the workpiece can be removed. Rather, an automatic retraction of the die is a very desirable operating feature for such a device.

Known fluid pumps have different types of check valves on, the valve seat of which is designed as an integral part of the housing of the respective device. Repair work on one Such a valve seat then require a revision of the entire housing, which of course makes the maintenance of these fluid pumps very expensive and difficult.

The invention aims to provide a way of operating to show a hydraulic pump, on which an automatic change in the operating mode takes place as soon as a predetermined pressure is reached. In addition, a pump set with two working speeds is to be created, with reduced overall dimensions a low-pressure part and a high-pressure part combined, using lines lying in series with a smaller one Number of can also be expanded separately thanks to the modular design and replaceable check valves, overall easily is to be installed and maintained, an operation with system of low and high pressure forces at one system point and automatic transition from working with low pressure to working with high pressure shows rapid tool advance to the occurrence of resistance to movement and requires an operator to continue working up to a predetermined maximum high pressure rather than one premature manual pressure relief in the system.

909849/0712

The object set is achieved according to the invention by a method for supplying a consumer with pressure fluid, as it is in Claim 1 is specified, as well as by pump sets for such a purpose, as characterized in claims 5-6 and 9 are. Advantageous refinements and developments within the meaning of the invention emerge for the method from patent claims 2 to and for the pump sets from claims 7 and 8 and 10 until 12.

The subject matter of the invention is therefore, on the one hand, a method for supplying a consumer with fluid at high pressure, which consists of charging the consumer with fluid at low pressure and high throughput a low pressure pump and compressing the fluid up to one includes high pressure with a high pressure pump. Furthermore, according to the invention, a pump set with two working speeds for the delivery of fluid from a reservoir to a consumer or user provided that a low pressure unit, a high pressure unit and a Contains usage unit. The low-pressure unit has a low-pressure pump for the delivery of fluid at low pressure, and high volume throughput with the maximum value for the low pressure limited by an automatic low pressure relief valve. The high pressure unit includes a high pressure pump for small volume, high pressure operation. Between the fluid reservoir and the low pressure unit and check valves are arranged between the low-pressure unit and the high-pressure unit. The usage unit contains a Check valve in a line leading to the high pressure unit and an automatically operated high pressure relief valve. The check valves are designed as exchangeable modules with hollow cylindrical components with seats for spring-loaded valve balls. According to a Another aspect of the invention is a pump set with two operating speeds provided that a low-pressure pump for automatic pre-charging of a fluid channel with a predetermined volume throughput and a high pressure pump for increasing the pressure in the fluid channel has up to a predetermined high pressure, and according to another aspect of the invention this leads to a combined, compact Set of coaxial, interlocking low-pressure and high-pressure pistons, of which the low-pressure piston has a larger working surface.

109849/0712

In summary, the invention can be described on the one hand as a Method for feeding a protective device or a work device with fluid at high pressure, in which a line from a low-pressure fluid pump precharged and then the fluid in the line is automatically brought to a high pressure with a high pressure fluid pump. To ' This method can further limit both d * e low as also belong to the high pressure through an automatically working relief valve. Furthermore, the invention provides an improved, of Hand operated hydraulic pump with two working speeds for the delivery of fluid from a reservoir to a protection device or a consumer. In this case, a first low-pressure pump with a high volume throughput charges a fluid channel down to a predetermined low level Pressure before, and a second high pressure pump then brings the fluid to you predetermined high pressure at which an automatic high pressure relief valve opens. Between the low pressure pump and the high pressure pump and the protection device, replaceable check valves in the form of modules are provided, which have a valve ball inside a hollow cylindrical component with a valve seat formed therein and include a loading spring therefor. Automatic pressure relief valves ensure a limitation of the fluid pressure in the pump. A manual release of the high pressure is very difficult if that automatic high pressure relief valve has not yet opened.

In the drawing, the invention is based on a preferred embodiment illustrates; show it:

1 shows a hand-operated compression tool with a pump set designed according to the invention in a partially sectioned side view,

FIG. 2 shows the pump set of FIG. 1 on a larger scale and with more details, also in a side view,

3 and 4 the pump set of FIG. 2 in end views of opposite sides,

FIG. 5 shows a longitudinal section through the pump set from FIG. 2 along a section line 5-5 shown in FIG. 8,

«09849/0711

FIG. 6 shows a section through the representation of FIG. 5 along the section line 6 - 6 in Fig. 5 »

Fig. 7 is a partially expanded section through the Illustration of FIG. 5 along the section line 7-7 in FIG. 5,

8 shows a plan view of the pump set from FIGS. 2 and

Fig. 9 is a schematic representation of the course of the line for the pressure fluid between the individual parts of the pump set of FIGS. 1 to 8.

In the illustration in FIG. 1, a pump set 10 forms a two working speeds! Part of a hand-operated compression tool 12 of the type as commonly etc. is for flanging, mounting, splicing of multi-core cables, and the like using _o This compression tool comprises a plurality of Eauptteile. On one find the pump set 10, a hand lever 14 is screwed to a threaded piece 16 with an internal thread, which has a handle 18 made, for example, of fiberglass or some other insulating material suitable for use in connection with high-voltage lines. The handle 18 contains in its hollow interior a chamber 20 for receiving a flexible bladder 22 with hydraulic fluid for the pump operation. The bladder 22 consists for example of neoprene rubber and has at one end a plug 24 which can be screwed into the handle 18 and thus serves as a holding element for the bladder.

As FIGS. 2 and 3 show, a lever carrier pO is attached to the pump set 10 by means of screws 32 screwed into openings provided therein, which lever carrier contains a through hole 34. A movable hand lever 36 shown in FIG. 1 has at one end a pair of ears 36, only one of which is visible in FIG. 1. A pin 40 passes through the bore 34 in the lever support 30 and through openings provided in the ears 38 holes therethrough so that the manual lever 36 permits and pivot away from the axis of the bore 34 as a pivot axis on the hand lever I4. The hand lever 36

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a hollow tube for example, is formed of fiberglass in the form, and it contains in its interior an axis extending along its axis rod 44 ^'a n one end of which a handle is articulated 42, the free end of a pivotally mounted on the hand lever 56 actuator, when actuated, 46 is moved via the rod 44 along the axial direction of the hand lever 56. In this way, the free end of the actuator 46 can be aligned to a manually operable pressure relief valve 48 which is arranged as shown in FIG. 1,2 and 8 manner shown on the pump set 10th As shown in FIGS. 1 and 5 , a pin 50 passes through holes in the ears JQ and also traverses a right- angled ΐΤ bracket 52 which has a slot 54 along which it engages an undercut 56 on a piston assembly 58.

In operations, the pin 40 serves as a pivot axis for the movable hand lever ~ j6 when it is pivoted towards or away from the hand lever I4. The pin 50 runs through an arc around the axis of the pin 40. The slot 54 in the bracket 52 loosely engages the undercut 5b on the piston assembly 50, so that the circular movement of the pin J> 0 results in a straight movement for the piston assembly 58 is implemented. Since the actuator 4 »is at a much greater distance from the pin 40 than the Ltift -JQ, the whirling force exerted on the pressure relief valve 48 is considerably less than that applied to the piston assembly 58. This complicates the operation of the pressure relief valve au while in Jrtuape prevailing high pressure. It is therefore easier for the operator to continue operating the pump in order to. To achieve the maximum pressure level 1 to be exerted on a specific workpiece, which is then followed by automatic pressure relief, rather than trying to lower the pump pressure by hand. This ensures that the full required compressive force is applied to the workpiece in any case «

As FIG. 1 further shows, at one end of the pump set 10 is a hydraulic drive member 60 attached. This drive member 60 contains a not visible in the drawing piston with hydraulic Feed and spring return that apply a mechanical force to a

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the free end of the power and drive member 60 attached crimping press 62 exercises. The crimping press 62 has a C-shaped body that a fixed jaw 64 and a movable jaw 66 carries, which can be moved by the hydraulic drive member 60 towards the fixed jaw 64 and away from it by a spring.

2, 3> 4 and 8 show further external details of the pump set 10. As can be seen in FIGS. 2 and 8, the pump set 10 has a protruding section with an external thread 70, to which the hand lever I4 with the internal thread of its threaded piece 16 can be screwed on. On this Torspringenden portion of the pump set, a groove 72 is also formed in which the open End of the flexible inserted into the hollow interior of the hand lever I4 Bladder 22 can be accommodated. As further FIG. 5 shows, is about the the end of the bladder 22 inserted into the rage 72 is fitted with a pressure ring 75, after you have screwed the threaded piece 16 onto the pump set is compressed by its inner surface and thus securely holds the end of the bladder 22 in place. ¥ ie Fig. 5 shows, are on the projecting one Section with the external thread 70 facing away from the end face Pump assembly 10 threaded holes 74 provided, the various Purposes such as the attachment of the one shown in FIG Drive member 60 or other tools on the pump assembly 10 can serve. Numerous other devices for the exploitation of hydraulic forces or devices for the generation of drive power for The pump set 10, such as, for example, pedals for foot actuation of the pistons, can be attached to the pump set 10 if desired.

In Fig. 9 is a schematic diagram for the hydraulic connections shown between the various components forming the pump set 10. The hydraulic fluid for the entire system comes from a common Eeservoir 80, the hydraulic fluid below atmospheric pressure, and it returns there. During the suction stroke of a low pressure pump 82, fluid is released from the Reading reservoir 80 via a fluid line 84 and a check valve 86 in a repressurization fluid line 88 sucked in. The check valve 86

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allows fluid flow only in that indicated by an arrow in FIG Direction out of the reservoir BO and prevents any fluid flow in the opposite direction. A low pressure relief valve 90 opens at a predetermined pressure in the low pressure fluid line 88 and then allows fluid to flow out of the low pressure fluid line 88 through a fluid line 92 to the reservoir 80. The fluid pressure in the low-pressure fluid line 88 thus never exceeds the predetermined pressure value established by the low-pressure relief valve 90. The volume of fluid pumped by the low pressure pump 82 is relatively large compared to the volume of fluid that one will be described in detail below High pressure pump 100 pumps.

It is readily apparent that the volume flow rate in the fluid flow a pump determines the speed at which the advance of a hydraulically operated device is against the minimum Forces of resistance. For example, it is desirable that the Die halves of a press using a low hydraulic Merge prints as quickly as possible. Venn then the die halves are brought together, a high hydraulic pressure is applied, to apply a great deal of force to a workpiece in the press or to keep the die halves close together.

The low pressure pump 82 is used to pump relatively large volumes of fluid with no more than a certain predetermined fluid pressure as determined by the opening pressure for the low pressure relief valve 90. The high-pressure pump 100 sucks fluid into a high-pressure pump line 104 via a check valve 102 during its suction stroke. mentions the low-pressure pump 82 has a greater volume throughput than the high-pressure pump 100. When the fluid circuit is under pressure for the first time is set, brings the low-pressure pump 82 with its greater fluid throughput Fluid from the low pressure fluid line 88 via the check valve 102 into the high pressure pump line 104 and then via a Another check valve 106 in a drive fluid line 108. laughs a sufficient volume of fluid is introduced into the system at low pressure, the high pressure pump 100 brings the fluid into the lines and 108 to a pressure which is that in the low pressure fluid line 88

«09849/0713!

maximum allowable and by the setting of the song pressure relief valve 90 exceeds the specified pressure.

A drive member or is attached to the drive fluid line 108 in FIG an Imtsungseinheit 110 connected. It can be "for example around the hydraulic drive member 60 for operating the Pig crimping press. 1 act. The low pressure pump 82 charges the high pressure pump line 104 and the drive fluid line 108 with a relatively high fluid throughput up until the predetermined low pressure value for the low pressure relief valve 90 has been reached in the low-pressure fluid line. This allows a relatively large volume of fluid to be supplied at relatively low pressure to IJutzeinheit 110, so that for example the moving die half of a flanging press quickly with a workpiece in Can be brought into contact. As soon as the Gesenkhäliten then on the workpiece are applied, high pressure fluid is supplied by means of the high pressure pump 100.

The drive fluid line 108 is connected to a high pressure relief valve 112 in connection, which opens when a predetermined value for the high air pressure is reached in the drive fluid line 108 and then a fluid flow into a fluid line 114 and through this to the Iteservoir allowed at atmospheric pressure. This becomes the iiaximal pressure developing in the drive fluid line 108 to a predetermined hole pressure value limited. The high pressure relief valve 112 remains open for a time sufficient for the Fluid pressure in the drive fluid line 108 is reduced significantly to a value much less than the maximum pressure in this line 108. The presence of the high pressure automatic relief valve 112 ensures that a predetermined limit pressure is generated for the care unit 110, laughing the high pressure relief valve 112 is activated, the pressure in line 108 is reduced to a sufficiently low value that a of Manually operated relief valve 116 can be easily operated by an operator. Actuation of the relief valve 116 enables an outflow of fluid from the drive fluid line 108 via a fluid line 118 back to the reservoir 80. The manual

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Relief valve 116 is open, the pressure in the fluid circuit is reduced to a linear value that is determined by the opening of the check valves 102 and 106 required Eestdruck is determined. i) aby, that the manual relief valve 11b only significantly Can operate less mechanical advantage than the high pressure pump 100, it becomes simpler and easier for the operator, the Maintain high pressure pump 100 operating to the point where high pressure relief valve 112 automatically opens as the relief valve 116 can be opened by hand with the high counterpressure on it.

The line diagram of FIG. 9 shows the hydraulic connections required for the operation of the pump set 100; the mechanical details for making these connections are shown in FIG. The representation in Pig. 5 initially shows a pump block 120, which is cast, for example, from an aluminum alloy and contains the required bores. 5 shows how the reservoir 80 for the hydraulic fluid can be obtained with the aid of the flexible bladder 22 of FIG. 1. The same reference numbers are used in FIG. 5 and in FIG. 9 to denote the corresponding components. Of course, however, the structural design of FIG. 5 does not represent the only possibility for a constructive implementation of the line plan of I ¹ Ig. 9 represents.

In FIG. 5, the reservoir 80 is connected to the fluid line 84, which is designed in the form of a bore in the pump block 120. The check valve 86 is disposed in the "οχιά in FIG. 5. 7 manner shown in a bore 122 in the pump block 120. In this case, the non-return valve is designed as an exchangeable module 86 and has a hollow cylindrical body 124, a spring 126 and a valve ball 128 which is seated on a valve seat 1J0 in the body. A fluid passage 1J2 provides fluid communication between the fluid line 84 and the hollow interior of the body 124. In a groove in the body 124 sits an O-Sing 154 which the module of the check valve 86 seals in the bore 122 »If the valve seat I30 is worn out, instead of expensive reworking of the pump block, the non-return valve 86 is simply replaced as a complete module.

SOiS4i / O71t

As already described, the fluid also flows in FIG. O via the check valve 86 to the valve pressure line 88, which is again formed in a bore in the uapen block 1. The x low pressure fluid line S3 is connected to the low pressure pipe 82, which is shown in FIG. -j has a pump chamber 138 which is formed between the end of an isohrung in the pump block 120 and a housing described in more detail below. A hollow cylindrical component is received in the bore I40, which component forms a low-pressure pump piston 144 and surrounds the housing I42. The piston 144 moves along the axis of the bore I40 and forms a cable of the piston assembly 58, which, as already described, moves under the action of by means of the hand lever; ^: 6 forces exerted on it can be caused to move in a straight line. A scraper ring I46 for the piston 144 is arranged i ^m pump block 120 near the outside thereof. An O-ring 148 and a support member 150 are arranged in a groove on the outside of the piston 144 and form a low-pressure seal for the low-pressure pump 82. In operation, when the piston 144 is withdrawn from the pump chamber I58, fluid is drawn from the reservoir 80 via the fluid line 84 and check valve 86 into the low pressure fluid line 88. On its inward stroke, the piston 144 exerts pressure on the fluid in the pump chamber 1J8 and in the low-pressure fluid line 88, thereby causing the valve ball 128 to sit on the valve seat 150, which prevents fluid from flowing through the fluid line 84 back to the reservoir 30. The check valve 102, on the other hand, opens and allows a relatively large volume of fluid to flow into the high pressure pump line IO4 in a manner which can be characterized as a high-speed flow. The fluid flows from the high pressure pump line IO4 through the check valve 106 to the utilization unit 110 (not shown in FIG. 5). In this way, pressure and fluid volume build up very quickly in the medium pressure fluid circuit, which initially includes the lines 88 and I04. The utilization unit 110 is fed with a relatively large volume of fluid by the low-pressure pump 82 through the check valve IO6. The low pressure relief valve 90 automatically operates to reduce the pressure in the low pressure fluid line in the predetermined manner. For this purpose, a Yentilkugel 154 is arranged in a bore in the pump block 120, which is in it under the

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= .: a spring I56 stands, whose tensioning force can be increased with the help of vcn screw holes 1 ^ 8 can be set, which are screwed into the hole 1 ^ 2 and are contained in their lütte ÜJTuiddurchlassthe one Allow fluid connection to fluid line 92 and to reservoir 80.

The high-pressure pump 100 has a high-pressure fluid caramer I60 which is connected to the high-pressure pump line I04. The high pressure fluid chamber 160 itself is formed by a central bore in the G-housing 142. A high-pressure pump piston 162 is arranged in this bore, which is designed as a solid and, in sum, low-pressure pump piston 144, coaxial cylinder. The piston 162 has a butt on its outside that accommodates an O-ring 164 and a support ring 166, which form a high-pressure fluid seal for the high-pressure pump 100. The piston 162 also has a longitudinal shoulder 168 which cooperates with a locking ring 170 in order to hold the high-pressure pump piston 162 coaxially with the low-pressure pump piston 144, as shown in FIG. 5. Another-Iiing Ί 69 forms a pressure seal. for the arrangement, Since the low-pressure pump piston 162 and the low-pressure pump piston 144 are combined ^into one structural unit, the stroke of both pistons 162 and 144 is egg φ. oak, but the effective piston area for the high pressure anpeiiko Ib en 162 is much smaller than that of the low pressure pump piston 1.4. The volume displacement of the high pressure pump 100 is therefore much lower than that of the song pressure pump 82. The ratio between the volume displacement of the two pumps 100 and 82 can be varied depending on the requirements in the respective application, by beingic; .ieli3v. ^T cirQ de: ·: liurchnecser of the high-pressure pump piston 162 and the bore facing it in housing I42 is changed. The housing 142 Tjoie'c has an externally threaded section I7I with which it is screwed into a bore iii Puiapenblock 120. In operation, after the supply of the required fluid volume at low pressure from the low-pressure fluid line 88 to the control unit 110, the high-pressure pump 100 sucks small amounts of fluid from the low-pressure fluid line 88 as required. the u1: - the rlas liicktJchlRgventil 106 with the utilization unit 110 in connection:, '; · divides. Hex Change from a high tolumen flow and low pressure operation to a high pressure and small operation

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Volume throughput occurs automatically as soon as the song pressure relief valve $ 0 opens. When working with the Lompressionswerkzetig 12 from i'ig, 1, the operator only needs to continue pivoting the hand lever J> b onto the hand lever I4 su and away from it, while the operation of the pump set 10 changes automatically as soon as the tool advance on resistance and the fluid pressure in the system rises above the level set on the low pressure relief valve 90. As soon as the maximum high pressure is reached in the system, the high pressure relief valve 112 opens automatically, which allows the system pressure to drop to a level at which the relief valve 116 can be easily operated for manual pressure reduction.

The check valve 102 is also designed in the form of an exchangeable module, and it has in the Pig. 5 ″ and 7, a biasing spring 172, a valve ball 174, and a hollow cylindrical component I76. The valve ball 174 forms a seal together with a valve seat provided on the component I76, and in the event of wear, the component I76 can be replaced. On the outside of component I76, a passage I78 is provided which allows fluid to flow to the lieder pressure relief valve 90. The check valve 106 can also be exchanged, and it comprises a pretensioning spring 180 and a valve ball 182 which is seated on a valve seat in a hollow cylindrical component I84 which is inserted into a bore 186 in the pump block 120. O-rings 188 and 190 form seals for the check valve 106. The check valve 86 is held in the bore 122 in the purapen block 120 by a clamping screw 192.

As FIG. 7 shows, the drive fluid line 108 is in fluid communication with a threaded portion in the bore 122, in the according to 5, the high pressure relief valve 112 is screwed in is. The high pressure relief valve 112 itself is, for example, a replaceable, modular spindle valve that is on a automatic opening at a fluid pressure of, for example, 700 bar (i0 000 pds / sg..in.) is set. Hach the response of the high pressure relief valve 112, the fluid pressure in the drive fluid line drops

B09849 / 0712 GPtäixti. kspected

considerably. The manually operable hydraulic valve 116 can then be easily operated and provides a fluid connection between the fluid lines 108 and 118, as shown in FIG. 5 and. 6 it can be seen that the pressure relief valve 116 itself contains a valve ball 194 which is under the tension of a lever 196 and can be lifted from its seat by a plunger 198 if this plunger 19O is shown in the above in connection with the illustration of the pressure relief valve 48 in i-'ig. 1 is pressed down by the actuator 46.

After the usage unit 110 has been fastened to the pump set, the reservoir 80 formed, for example, by the bladder 22 with the plug 24, is filled with hydraulic fluid. Air that is undesirably compressible must be expelled from the system. This is done by actuating the pump until the low-pressure relief valve 90 opens. Then, while the pump continues to operate, the relief valve 11 o is kept open. Finally, work continues until the high pressure relief valve 112 responds. This procedure drives very quickly all the bubbles in the lieservoir 80 \ o the air easily Hachfiillen of hydraulic fluid may be displaced, so that an air-free i'luidfüllung results. The series connection of the non-return valves and one of the high-pressure relief valves allows all air to be removed from the system quickly and easily.

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Claims (1)

2921359 Dr. HATE - Dr. FRANKE - Dr. ULLRICH PATENT LAWYERS IN MÖNCHEN AND HEIDELBERG P 94/444 2'yy 1979 Dr.p / ü ¹ minute Claims s s sa ss ss sssss as s Γ 1 ·) A method for supplying a consumer with pressurized fluid, characterized in that in a first step a high-pressure fluid line connected to the consumer is precharged from a low-pressure fluid pump with a relatively large delivery volume and that in a second step i-fluid in the high-pressure fluid line a high pressure fluid pump is brought to high pressure. 2. The method according to claim 1, characterized in that of the Low pressure fluid pump generated fluid pressure to a predetermined value is limited, when it is reached, it automatically switches to high pressure operation. 5. The method according to claim 1 or 2, characterized in that the High fluid pressure in the high pressure fluid line is limited to a predetermined value by an automatically operated relief valve. 4. The method according to claim 3 »characterized in that in the High pressure fluid line remaining residual fluid pressure is released through a manually operated relief valve, the opening of which is below High pressure in the high pressure fluid line requires more work than continuing the pump operation. 5. Pump set for the delivery of fluid from a reservoir to a consumer with two working speeds, characterized by a fluid channel (1O4 »10 ^Q ) connected to the consumer (11O)» through a low pressure pump (82) for automatic pre-charging of the i'luidkanals bis to a predetermined low pressure with a predetermined first volume throughput and by a high pressure pump (100) for charging the fluid channel up to a predetermined high pressure with a smaller second volume increase. 809849/0712 6. louapengarnitiir for the waste of Js ¹ IuId from a water reservoir cn a consumer with two working speeds, ^ ekennrieiormct auroh one low pressure unit nit siner iLiederarticlcfluidleittm ^ (öö), a ^ ieäigemluid urucl: in large volume throughsata from the ..eeervoir (80) into the song pressure fluid line, a first jr-ückschla ^ valve (86) with an iTuidfiun only yoa keservoir for song pressure fluid line permitting Iitirchlaßriclituns and an automatic liiederdruclcentlastungsventil (yo) for a pressure relief valve also the low pressure fluid line reservoir "when the oil pressure exceeds a predetermined low pressure value in the low pressure fluid line, through a high pressure unit with a high pressure pump line (104) and a second check valve (102) with a high pressure pump line only from the low pressure fluid line to the low pressure fluid line permissible transmission direction and a high pressure pump (IOO) with a small volume throughput for sucking in fluid from the corset pressure fluid line and for charging this fluid to high pressure and through a high pressure fluid channel with a high pressure fluid output line (IO8) in fluid connection with the consumer (HO), a third check valve (106) with a flow direction only from the high pressure fluid outlet line to the high pressure fluid outlet line, an automatic high pressure relief valve (112) for allowing fluid flow from the high pressure fluid outlet line (108) to the ice reservoir when the fluid pressure in the high pressure fluid outlet line exceeds a predetermined pressure value and a manually operated high pressure fluid outlet valve (manually) for allowing fluid flow between the high pressure fluid output line and the reservoir. 7. Pump set according to claim 6, characterized by a pump block (120), the non-return valves (86, 102, IO6) as exchangeable Contains modules. 8. Pump set according to claim 7 »characterized in that each of the liückschlagventilmoduln has a peder (I96, 172, I8O), a valve ball held under tension by this spring (194» 174 »182) and a hollow cylindrical component (176, I84) for the Has receiving the spring and the valve ball with a valve seat for the valve ball. 809849/0715 bad OfiiGiNAL 2921351 9. Puiapengarnitur in compact design with two working speeds, characterized by a low-pressure pump (82) with a hollow cylinder piston (144) by a high-pressure pump (lüü) with an inside of the low-pressure pump piston and a piston (162) arranged coaxially with it massive cylinder, through a low-pressure fluid line (88) that can be pressurized by the low-pressure pump, through a perforated pressure pump line (104) and a check valve (102) with a flow direction from the low-pressure fluid line to the high-pressure pump line, which allows initial pre-charging the liochdruckpuapenleitung with i'luid tone of the i; iederdruckpiTiape low pressure and high Yolumendurchsatz and a subsequent pressurizing £ au this i'luid by the high-pressure pump high pressure and low volume throughput examples permitted. 10. pump kit according to claim 9> characterized by a low pressure relief valve ($ 0) responding at a predetermined pressure level for the fluid in the liiederdruckfluidlei "exercise (88). 11. Pump set according to claim 9 or 10, gekennzeiclinet by a at a predetermined pressure level for the I'Tuid in the high pressure pump line (IO4) responsive high pressure relief valve (112). 12. Umpengamitur according to one of claims 9 to 11, characterized in that the hollow cylindrical low pressure pump piston (144) has a larger working surface than the solid cylindrical high pressure pump piston (62) and thus conveys a greater amount of fluid than this with each stroke. Ö09849 / 0715