EP3242017B1 - Pressure intensifier for screw-in - Google Patents

Description

Subject of the invention

The invention relates to a preferably hydraulic pressure booster according to the preamble of claim 1.

As a pressure booster, a device is referred to here, which automatically produces from a drive fluid available under low pressure, without additional external drive, a higher pressure of his output working fluid. The details of such a device will be explained in more detail later.

Technical background

Such pressure intensifiers are used in many areas. The following application areas are not exhaustive. For example, such pressure boosters are used to generate a high pressure water jet for a cleaner using the low pressure vehicle hydraulics, or to operate a rescue shears to rescue inmates from high pressure vehicles. Even in industrial applications, such pressure intensifiers are used in a variety of forms, for example to supply clamping tools or rotating chucks with the high pressure required for clamping. The clamping tools may be used in industrial manufacturing clamping tools or clamping tools used during assembly, and the rotating chuck may be part of a machine tool or, for example, a drill string for performing earth drilling.

The pressure intensifiers can be used individually or cascaded in series, if a particularly high Pressure is generated, which can not be achieved with the help of a single booster amplifier.

State of the art

The pressure intensifiers known in the prior art are typically connected via high pressure hoses or hydraulic pipes to the hydraulic block, which supplies them with hydraulic fluid under low pressure and receives used hydraulic fluid. The connection to the high-pressure consumer, which is supplied with the hydraulic fluid generated by the pressure intensifier, under increased pressure, is usually carried out via hydraulic hoses or tubes.

The connection of a pressure booster with the help of high-pressure hoses or pipes to the hydraulic system supplying it and possibly also to the consumers supplied by it is problematic. This is partly because hydraulic hoses can age over time and then tend to leak. Hydraulic pipes can become fatigued over time, especially when exposed to oscillating loads. The problem is the connection with hydraulic hoses or pipes even where several pressure intensifiers are used, for example because they are cascaded in series. This usually results very quickly space problems and the system can not be kept as compact in the end, as would actually be desirable. Particularly problematic is the use of hydraulic hoses in rotating systems, where the pressure booster rotates with.

Also, the idea of a direct flange of a pressure booster to a hydraulic block, so that the Outer surfaces of the pressure intensifier and the hydraulic block in a plane can be pressed tightly against each other and tubeless fluid can be handed over is critical. Such flanges require in the transverse direction considerable space, a high Verschraubungsaufwand and also throw at high pressures on sealing problems.

A pressure booster according to the preamble of claim 1 is known from the document DE 196 33 258 C1 ,

The problem underlying the invention

The invention is therefore an object of the invention to provide a pressure booster, which can be connected tube and tubeless and thereby very reliable to a hydraulic block. This object is achieved with the features of claim 1.

Claimed is a - usually ready to operate, only the connection to a pressure supply, a tank connection and a consumer for the higher pressure it requires - pressure booster for fluids, especially for liquids. The pressure booster thus forms a ready-to-use unit for completely or partially introducing it into a hydraulic block.

The pressure booster consists of a cylinder block in which a pressure booster piston and a control piston move cyclically. The control piston can assume different positions and thereby predefines the working cycles of the pressure intensifier piston, wherein the control piston is not actuated by a mechanical positive control in the manner of a camshaft, but purely by pressure difference. The pressure intensifier is in turn designed so that it, when it has reached a certain position, one Changes in the pressure conditions initiated on the control piston, so that it changes its position.

The pressure booster piston is preferably designed as a differential piston with two different sized, hydraulically effective piston surfaces, in any case, it forms a high-pressure working chamber and a low-pressure working space in the cylinder block. The pressure booster piston is usually solid, d. H. it preferably has no through holes that connect, for example, the high pressure working space and the low pressure working space. Instead, the pressure intensifier piston usually has a constriction in the region of its circumference, which forms a gap which is located between the high-pressure working chamber and the low-pressure working chamber.

The cylinder block has an external connection for supplying pressurized fluid from outside, which is also called low-pressure connection - because the pressure of the fluid present here is lower than the pressure of the discharged from the pressure booster to the consumer fluid.

The standing under said low pressure fluid is intended to perform work in the pressure booster and possibly also serves as a basis for generating and output of high pressure fluid, that is, a fluid which is under a higher pressure than the low pressure fluid. In any case, the high-pressure fluid is discharged via an external high-pressure port as under a higher pressure working fluid to the outside to an external consumer.

Finally, the pressure booster has a connection for the discharge of fluid, whose working capacity is exhausted in the pressure booster. This connection is in the Also referred to as tank connection, even if it does not necessarily lead to a tank in the strict sense. It should also be mentioned that the said gap usually forms part of a channel leading to the tank connection.

As the cylinder block of the pressure intensifier is here preferably understood a solid metallic body containing all cylinder bores and channels, which are required for cooperation of the pressure booster piston and the control piston. In the vast majority of cases, the solid metallic body has at least in the region of the control piston and the pressure booster piston everywhere cross sections in which the area occupied by the solid material in cross section, is greater than the area occupied by the cylinder bores and the channels in the cross section ,

The cylinder block of the booster has a rigidly connected to him coupling portion. The coupling portion is configured to be inserted into a receiving bore of a hydraulic block. He is designed so that the receiving bore encloses the coupling portion on its circumference and usually also the front side. In this case, the coupling section has at least two fluid transfer regions which are fluidically separated from one another by a seal and serve for the exchange of fluid between the pressure intensifier and the hydraulic block into which it is inserted.

The fluid transfer areas are positioned on the coupling portion so as to be located inside the hydraulic block into which the coupling portion has been inserted, below the outer surface of the hydraulic block against which the non-hydraulic part of the hydraulic block is inserted Pressure booster rests. As a rule, the fluid transfer areas are at least 20 mm, more preferably at least 30 mm below the surface of the hydraulic block.

As a result, a particularly compact and reliable fluidic connection between the pressure booster and the hydraulic block of the machine is produced, which supplies the pressure booster. The fact that the fluid transfer areas are located far in the interior of the hydraulic block, and thus arranged in a very rigid area, even under high pressure can easily achieve a reliable seal - even if disturbing factors such as vibrations are added.

Preferably, the pressure booster is designed so that in a fluid transfer area from the interior of the cylinder block of the pressure booster coming a channel opens, via which the pressure booster emits fluid during operation, the workable within the pressure booster working capacity is exhausted. In this case, in another fluid transfer area another channel opens, also coming from the interior of the cylinder block. Low-pressure fluid, ie fluid which drives the pressure intensifier and possibly also forms the basis for generating fluid under higher pressure and to be delivered to a consumer, is fed via this channel into the pressure intensifier.

Ideally, the coupling portion has a third fluid transfer area for transferring the higher pressure working fluid to the hydraulic block. In this case, there is no need for any pipes or hydraulic hoses to connect the intensifier with its environment and thus make it ready for use. Instead, find an immediate one hydraulic connection between the cylinder block of the pressure booster and the hydraulic block instead.

Ideally, at least one of the fluid transfer regions comprises an annular groove running around in the peripheral circumferential surface of the coupling section. In this way it is ensured that the corresponding fluid transfer area is securely connected to the corresponding bore in the hydraulic block, regardless of whether the coupling portion of the pressure booster has been pushed slightly more or less deeply into the hydraulic block, or what twisting position of the coupling portion takes in there.

As a rule, the coupling section has an external thread for screwing the coupling section into the hydraulic block. In this way, the coupling portion is mechanically anchored securely in the hydraulic block.

The plurality of fluid transfer regions are preferably arranged between the free, to be introduced into the hydraulic block end of the coupling portion and the external thread of the coupling portion. The outer diameter of the coupling portion usually tapers at the transition between the external thread and the rest of the coupling portion. Typically, the cylinder block of the booster has a molded hex for attachment of a screwing tool.

Preferably, the coupling portion of at least two parallel to the longitudinal axis of the pressure booster extending bores, which extends from the free end face of the coupling portion into the region of the cylinder block of the Extend pressure booster, which is always positioned outside of the coupling portion receiving hydraulic block.

With such bores in the coupling section running parallel to the longitudinal axis of the pressure intensifier, it is easy to produce the required fluidic connection between the corresponding channels in the interior of the cylinder block of the pressure intensifier and the fluid transfer regions. The holes can be introduced from the front side of the coupling section forth in one operation until they intersect with the channels to be connected through them in the interior of the booster. In particular, such bores make it very easy to form one of the fluid transfer areas on the free end face of the coupling section and the other of the fluid transfer areas in the area of the peripheral surface of the coupling section.

Independent protection is claimed for a hydraulic unit with a hydraulic block in which a plurality of hydraulic fluid flows through bores for connecting different hydraulic active elements (controllable or non-controllable valves and / or pumps and / or pressure equalization tank and / or more pressure booster) are formed, and at least one Pressure booster of the type according to the invention has, wherein the pressure booster has a coupling portion which is inserted into a bore in the hydraulic block and fixed there.

It is particularly favorable if at least two, better three, pressure boosters are connected in series to one another on the hydraulic unit, so that the pressure booster preceding from a (high pressure) flow direction supplied high pressure represents the pressure with which a flow direction downstream pressure amplifier is fed on the input side. In this way cascading can produce particularly high pressures. In this case, the hydraulic unit can be made particularly compact, since the pressure booster need no piping or hydraulic hoses for connection to the hydraulic block and therefore packed very close to each other can be attached to the hydraulic block.

Further advantages, effects and design options of the invention will become apparent from the following description of the embodiments with reference to FIGS.

list of figures

• The FIG. 1 shows the developed in a single plane hydraulic circuit diagram and the conditions during a working stroke of the pressure intensifier piston.
• The FIG. 2 shows the same developed in a single plane hydraulic circuit diagram and the conditions at a time when the pressure intensifier piston has reached its top dead center after a power stroke.
• The FIG. 3 shows the same developed in a single plane hydraulic circuit diagram and the conditions during a charging cycle of the pressure intensifier piston.
• The FIG. 4 shows based on the FIG. 1 the conditions in normal operation, in which using a corresponding connected external switching valve fluid is generated, which is output under high pressure.
• The FIG. 5 shows based on the FIG. 1 the conditions in the switching operation, in which the high-pressure consumer is depressurized using the appropriately switched, external switching valve back through the pressure booster or even emptied.
• The FIG. 6 shows a first, physically concrete embodiment of the pressure intensifier according to the invention.
• The FIG. 7 shows - as an excerpt from the FIG. 6 - The coupling portion of the booster.
• The FIG. 8 shows a second, physically concrete embodiment of the pressure intensifier according to the invention.
• The FIG. 9 shows the pressure booster according to FIG. 8 in enlarged half section.
• The Fig. 10 shows the embodiment gem. Fig. 6 and 7 in detached from the hydraulic block state, shown in perspective.
• The Fig. 11 shows the embodiment gem. Fig. 6 and 7 in the state removed from the hydraulic block, in side view.
• The Fig. 12 shows the embodiment gem. Fig. 8 and 9 in detached from the hydraulic block state, shown in perspective.
• The Fig. 13 shows the embodiment gem. Fig. 8 and 9 in the state removed from the hydraulic block, in side view.

embodiments Basic working principle of the pressure booster described as an exemplary embodiment

First, the basic principle of the pressure booster according to the invention is to be explained, which is characterized by its particularly simple structure and therefore predestined to create a particularly compact pressure booster, so that just working on this principle pressure booster are predestined to be equipped with the connection which forms the core of the invention.

This is on the Fig. 1 directed.

The Fig. 1 shows the pressure booster 1, which is completely formed in a metal, preferably steel cylinder block 13 which is cut here and therefore initially only schematically represented by four solid lines forming a rectangle as a box-like outline. The cylinder block preferably has the outer contour of a cylinder that is rotationally symmetric about the longitudinal axis L. The cylinder block 13 consists of at least two and ideally three separate, ie separable from each other, materially not interconnected cylinder block elements. In the concrete of Fig. 1 shown, preferred embodiment, the cylinder block 13 of the three cylinder block elements 13.1, 13.2 and 13.3, as indicated by the dashed lines. The plurality of cylinder block elements are mutually positively fixed relative to each other in a defined position, for example using not illustrated here dowel pins.

In this cylinder block works a pressure booster piston 2. This pressure booster piston 2 is typically designed as a differential piston with two different sized, effective in the opposite direction effective hydraulic active surfaces and then consists of a low-pressure piston N with a large diameter and a high-pressure piston H with a small diameter fixed to each other are connected by a piston stem S. The low-pressure piston N forms a low-pressure working chamber 10 in the cylinder block, while the high-pressure piston H forms a high-pressure working chamber 11 in the cylinder block. Between the two pistons in the region of their connection through the piston shaft S, a gap 12 is formed, whose function will be explained later. The pressure booster piston preferably has a longitudinal axis which is parallel to the longitudinal axis L of the cylinder block 13.

It is easy to understand that the gear ratio, i. H. the factor by which the supplied low pressure can be increased depends on the diameter ratio DN / DH of the low pressure piston N and the high pressure piston H.

In addition, in the cylinder block 13, a control piston works 3. Preferably, its longitudinal axis is parallel to the longitudinal axis L of the cylinder block 13. Ideally, the control piston and the differential piston are completely or at least predominantly arranged side by side, seen perpendicular to the longitudinal axis.

As can also be seen, in the cylinder block 13, all the connection lines required to make the pressure booster operational are made. It should be noted that the Fig. 1 the pressure intensifier piston 2, shows the control piston 3 and all the necessary connection lines for better clarity in a plane projects. Preferably, ie in reality, said components are not all in one plane, because such an arrangement would make only extremely bad use of the cross-section of the cylinder block Fig. 1 Drawn plane, the piston and the connecting lines would crowd, while in a longitudinal axis also included cutting plane perpendicular to this no piston and almost no connection lines would be found.

To the outside, the pressure amplifier communicates via its external low-pressure connection 5 with an external low-pressure source. From this, the pressure intensifier draws lower pressure hydraulic fluid that drives it. Preferably, a portion of these under low pressure in the pressure amplifier fed hydraulic fluid is placed in the pressure booster under higher pressure and output as under higher pressure hydraulic fluid from the pressure booster to an external consumer. In addition, the pressure booster has an external tank connection 6, via which it discharges at least part of the lower-pressure hydraulic fluid to the outside when this hydraulic fluid has performed its work within the pressure booster. The delivery is preferably to an external tank or an external hydraulic fluid reservoir, but this is not mandatory. In addition, the pressure intensifier has another connection, the so-called external high-pressure port 7. Via its high-pressure connection, the pressure intensifier gives it hydraulic fluid set under a higher pressure (compared to the feeding lower pressure) Working machine, such as a rescue scissors, a clamping device or a hydraulic collet chuck. As far as the term "external connection" is used here, this means that a connection is external, because the pressure amplifier can be connected directly to the environment via this connection. In contrast, there are internal connections, such as connection channels, which are connected to each other in the interior of the booster whose hydraulic functional components.

How to use the Fig. 1 sees, connects to the external port 5 to the low pressure source within the cylinder block 13, a low pressure line 8 at. The low pressure line 8 branches soon. It branches into a low-pressure line section 8.1, which serves primarily to feed the high-pressure working space with fresh low-pressure fluid, and moreover also serves to supply the control piston 3 with low pressure via the low-pressure line section 8.4. The preferably existing low pressure line section 8.2 leads past the high pressure working space directly into the line leading to the high pressure consumer. The low pressure line section 8.2 is used, if present, to fill a newly connected, still empty high pressure consumer first with low pressure fluid and the air from the u. U. initially empty lines of high pressure consumer to displace, so that then can be started with the high pressure generation.

At the connection 6 to the external tank is followed by a tank or return line 9. The tank or return line 9 branches within the cylinder block 13 at once into a return line section 9.1, which comes from the control piston ago, and a line section 9.2, the as will be discussed later, in due course and with a corresponding, usually provided by external hydraulic circuit of the pressure booster as a control line for the controllable check valve 4.3 is used.

In addition, a connecting line 14 is provided from the control piston to the pressure booster piston, whose function will be explained later in more detail.

To the control piston 3 is to say that this control piston 3 is also designed as a differential piston.

Based on Fig. 1 can explain the basic operation of the intensifier quite clearly:
In the phase that the Fig. 1 shows, currently takes place a power stroke, ie, the pressure booster piston 2 moves in the direction of the black arrow in the high-pressure working chamber 11 inside. At the beginning of the power stroke, the high-pressure work chamber 11 is initially filled with low-pressure fluid, ie preferably with fluid that is under the low pressure of the feed pump. By moving the pressure intensifier piston into the high-pressure working space 11, the fluid located there is pressurized and discharged via the check valve 4.2 and the external high-pressure connection 7 to the high-pressure consumer.

The low-pressure working space 10, which continuously increases in the course of the working cycle, is continuously filled with low-pressure fluid, ie with fluid drawn in via the low-pressure via the external low-pressure connection 5. This refilling is done via the connecting line 14. This is by means of the control piston 3 - namely on the slimmed region V1, which is between the terminals C and P - connected to the low-pressure line section 8.4, which leads to low-pressure fluid.

The control piston 3 remains in the of Fig. 1 shown position. Although it is at its one (here the lower) end face on the low pressure line section 8.3 constantly subjected to low pressure. At the same time, however, it has been subjected to low pressure since the beginning of the power stroke at its opposite (here the upper) end side via the control line 8.5. This is because the high-pressure work space has been filled with low-pressure fluid at the beginning of the power stroke using the low-pressure line section 8.1. The low pressure in the control line 8.5 is maintained even when the high-pressure piston has passed over the mouth of the control line 8.5 in the high-pressure working space and thereby sealed. Due to the fact that the low pressure on the upper end face of the control piston 3 acts on a larger area than on the lower end face of the control piston 3, a resultant force permanently acts on the control piston.

It is important to mention that the gap 12 is also connected to the external tank port 6, that is kept pressureless. This is necessary to be able to dissipate any leakage which possibly flows from the high-pressure working chamber and / or from the low-pressure working space into the intermediate space 12, so that no disturbing counterpressure can build up in this intermediate space, because possibly hydraulic fluid is trapped.

The power stroke continues until the pressure booster piston 2 of Fig. 2 shown position, ie has reached its top dead center. How to use of the Fig. 2 sees, the high-pressure piston of the intensifier piston is now so deeply penetrated into the high-pressure working chamber 11 that its the gap 12 facing edge has now released the mouth of the control line 8.5 again, so no longer passes over and thereby seals. As a result, the mouth of the control line 8.5 is connected to the unpressurized gap 12, ie the pressure that has prevailed during the working cycle in the control line 8.5, breaks down. Because of this, only one end face of the control piston is now subjected to low pressure, namely here in the picture, the lower end face of the control piston 3. Therefore, the control piston 3 is pushed into its other position, ie from the of Fig. 1 shown position in the of Fig. 2 transported position shown.

As a result of the said displacement of the control piston 3 in its second position whose slimmer region V1 is no longer hydraulically connected to the connecting line 14. Instead, the connecting line 14 is hydraulically connected via the second streamlined area V2 of the control piston 3 to the return line section 9.1. This leads to the fact that the low pressure in the low-pressure working chamber 10 collapses because the low-pressure working space 10 is now switched without pressure. As a result, now outweigh the forces acting on the upper face of the high-pressure piston, which is why the pressure booster piston 2 now begins to move down and displace the hydraulic fluid still in the low-pressure working chamber 10 via the connecting line 14 and the return line section 9.1 so that it over the external tank connection 6 is discharged.

While the Fig. 2 shows the top dead center, ie the moment in which the pressure booster piston 2 had stopped in its movement and the direction of movement changes, shows the Fig. 3 the charge cycle, during which the pressure booster piston 2 again penetrates deeper into the low-pressure working space. The snapshot that the Fig. 3 shows, shows the intensifier piston just before its bottom dead center, but currently it is still moving down.

Based on Fig. 3 can already be guessed what will happen soon: It can be seen that the high pressure working chamber 11 facing edge of the high-pressure piston is about to connect the mouth of the currently unpressurized control line 8.5 with the currently under low pressure high pressure working chamber 11. As soon as this is done, the currently prevailing in the high-pressure working chamber 11 low pressure on the control line extends from 8.5 and reaches the previously unpressurized (upper) end face of the control piston 3. As soon as pressure is present, the control piston 3 is driven downward because the previously unpressurized End face has a larger area than the permanently under low pressure other, smaller face of the pressure intensifier piston.

Once the control piston 3 has then been driven back into its other position, its slimmed-down region V1 will again connect the connecting line 14 with the low-pressure low-pressure line section 8.4, so that the pressure in the low-pressure working chamber 10 changes again. The currently not under external pressure low pressure working chamber 10 is then acted upon again with the low pressure of the low pressure source. At this moment, the pressure booster piston 2 reaches its bottom dead center, holds short held. The charging cycle comes to an end and a new work cycle, as of Fig. 1 shown, begins.

It should also be noted that an essential advantage of today's invention is that the control piston works without a spring. The otherwise necessary application of the closing force of a spring is replaced by the constant admission of a front side with the low pressure. This contributes to the achievement of the goal to build smaller the pressure booster, since the space required for the placement of the most replaceable subsequently replaceable spring required space is eliminated.

Based on Fig. 4 It is easy to see what the reason for this is with the return line section 9.2, which leads from the tank or return line 9 up to the controllable check valve 4.3.

This line serves to relax the high pressure consumer at the appropriate time.

To do this, so to speak reversed by means of a preferably externally arranged switching valve, ie the previously connected to the external low pressure port 5 is connected via a preferably external, lying outside the cylinder block 13 now depressurized or connected to the tank and the previously with the external tank connected terminal 6 is now connected to the low pressure source. Because of this, low pressure can be supplied to the control piston via the return line section 9.2 to the control piston, which opens the controllable check valve 4.3, so that the previously closed by the check valves 4.1 and 4.2 with respect to the environment line to the high pressure consumer via the now unpressurized Low pressure line section 8.2 hydraulic fluid through the previous low pressure line 8 and the now unpressurized, recent low pressure port 5 can dissipate.

Now is even closer to explain how the controllable check valve 4.3 works.

The pressure intensifier according to the invention is operated with a preferably externally mounted changeover valve 25. In normal operation, the switching valve 25 is switched so that the already based on the FIGS. 1 to 3 discussed operation takes place, is generated in the high-pressure fluid, see. Fig. 4 ,

In order to relax the high-pressure consumer, which is regularly required, for example, if it is a clamping means to release the workpiece clamped by him at the end of processing and again, the switching valve 25 is switched to the position as the FIG. 5 shows. Basically, nothing happens except that the external connections 5 and 6 are "reversed". The port 5, via which the externally generated low pressure has been fed so far, is now switched depressurized and thus corresponds to the tank or. Return connection. The previously operated as a tank or return port external port 6 is now, z. B. via the external low-pressure feed pump 26, subjected to low pressure and thus even to the low-pressure connection. This has the consequence that the line section 9.2 is no longer depressurized, but now low pressure leads. This low pressure lifts the valve body of the controllable check valve 4.3 from its seat, so unlocks the check valve 4.3. Thereafter, the previously stored in the high pressure consumer hydraulic fluid flows through the check valve 4.3 and the line 8.2 in the tank. The Of course, as a result that immediately collapses the pressure in the high pressure consumer and then emptied the hydraulic system of the high pressure consumer in the tank, whereupon the high pressure consumer can be decoupled, which is very convenient, for example, if it is a rescue scissor and the use terminated is.

Remarkable is still in the Fig. 1 to 4 to recognize, forming a throttle pilot hole. While the pilot control bore in the figures is symbolized by way of example as a bypass throttle 24 *, in reality it is preferred that the pilot control bore penetrates the right-hand hatched upper part of the control piston 3 to be recognized in the figures. It connects the region of the upper free end face of the control piston 3 with the slimming V1. In this way, the control line 8.5 is permanently connected to the slimming V1. This pilot hole has the purpose even then to ensure a defined position of the pressure booster piston 2 when the pressure booster has stood still for a long time. As long as the pilot hole is missing, it may happen that after a long stoppage of the pressure booster piston, the control line 8.5 has lost the pressure trapped in it by microleakages and the control piston 3 then assumes an undefined position, which makes restarting difficult. The pilot hole has the purpose to always ensure that the control line 8.5 is still correctly pressurized even after a long time and therefore forces the control piston 3 in a defined position, which makes it easy to restart the pressure booster. The flow flowing through the pilot hole is chosen so that it is so small that it does not matter during operation. Only in longer downtime adds up the running over the pilot hole bore flow and thus shows the desired effect, as described above.

The invention essential coupling section

The Fig. 6 and 7 show a concrete, physical embodiment of a pressure intensifier according to the invention.

The FIG. 7 shows the coupling portion of the booster gem. Fig. 6 in an enlarged view.

The Fig. 6 shows the pressure booster 1 according to the invention in its mounted on an external hydraulic block 100 position. The hydraulic block is not part of the pressure booster, but represents, for example, the hydraulic control block of a clamping device. The hydraulic control block is actually a solid metal control block (no pipe sleeve o. Ä.) In which a plurality of hydraulic channels is formed and the z. B. also includes the actuator over which the user controls the system hydraulically.

As can be seen, the cylinder block 13 or its cylinder block element 13.1 integrally merges into a coupling section 101, i. H. a part of the circumferential surface of the cylinder block of the booster forms the coupling portion 101.

The coupling portion 101 has a circular cylindrical shape. Preferably, it has a reduced diameter compared to the rest of the generally likewise cylindrical cylinder block 13, ideally by at least 30%.

The diameter of the coupling portion 101 preferably corresponds to the core diameter of a metric thread and is reduced by a tolerance measure that allows the non-male threaded portion of the coupling portion 101 to pass through the female threaded portion of the hydraulic block 100.

The length of the coupling portion 101 in the direction of the longitudinal axis L of the booster 1 is preferably at least 25%, more preferably at least 30% of the total length of the cylinder block 13 of the booster 1. This ensures that the coupling portion 101 can penetrate deep enough in the hydraulic block 100, in an area that is located in the solid material of the hydraulic block, below the most planar surface of the hydraulic block 100 surrounding the bore for the introduction of the coupling portion 101.

As a rule, it is the case that the coupling section 101 is surrounded in its installed in the hydraulic block 100 at its periphery around (possibly by local channels through) solid material of the hydraulic block, seen in the radial direction has a thickness which is at least about The factor 1.5 is larger than the largest radius of the circular cylindrical cylinder block 13. Thereby, the fluid transfer can take place where the hydraulic block 100 has a high strength or rigidity. In this context, it should be remembered that the "low pressure" or lower pressure supplying the pressure intensifier, in absolute terms, must by no means be a low pressure. Because where a very large pressure difference must be overcome, the pressure intensifier according to the invention can be used cascading, ie a subsequent pressure booster is then fed by the high pressure of the previous booster.

The coupling portion 101 not only provides a fluidic connection between the pressure booster 1 and the hydraulic block 100, which is supplied by the pressure booster. Rather, he keeps the pressure booster 1 also mechanically in its installation position by the weight and all forces occurring during operation due to the mass of the booster 1 predominantly or completely receives and passes on to the hydraulic block 100, z. B. the acceleration forces that occur at the pressure booster when the hydraulic block rotates or moves.

The coupling portion 101 is configured to be inserted and fixed in a bore of the hydraulic block 100 receiving it.
For this purpose, the coupling portion 101 is preferably provided with an external thread 102, which is screwed into a corresponding counter-thread of the coupling portion 101 receiving bore in the hydraulic block 100.

As can be seen, the coupling portion 101 is designed so that it can completely enclose the receiving bore of the hydraulic block 100 at its periphery and at its free end face.

How best to use the Fig. 7 sees, two fluid transfer areas 104 and 105 are formed on the coupling portion 101. They are seen in the direction of the longitudinal axis L of the booster one behind the other and seen in the screwing of the coupling portion, if necessary, before the provided with an external thread 102 portion of the coupling portion.

The first fluid transfer region 104 is preferably formed on the peripheral surface of the coupling portion 101. The second fluid transfer region can either also be formed on the peripheral surface of the coupling portion 101 or preferably on its free end face.

The pressure intensifier communicates directly with the hydraulic block 100 via these fluid transfer regions 104, 105 (and only via these). These two fluid transfer regions are hydraulically separated from one another by a seal 106. The seal is preferably designed as a seal inserted with or without a support ring in a circumferential annular groove on the coupling section. In addition - preferably in the same way - another seal 107 is provided which seals the lying closer to the outside fluid transfer region 104 to the outside.

The coupling portion 101 preferably has two bores 108 and 109 extending generally parallel to the longitudinal axis L. These extend from the free front end of the coupling portion 101 through the coupling portion into the region of the cylinder block 13 (or 13.1), which also at the hydraulic block mounted pressure booster outside the hydraulic block 100 is located.

The one hole 108 goes into the of the Fig. 1 to 5 shown low pressure line 8 via. This bore preferably opens into the free end face of the coupling section and here constitutes the external low-pressure connection 5 (cf. Fig. 1 ) of the pressure booster.

This is located in the fluid transfer region 105, via which the pressure booster can be connected to the low-pressure feed line, which opens here in the bottom of the bore of the hydraulic block 100, which receives the coupling portion 101. The fluid transfer area 105 is designed to that a fluid-conducting connection between the pressure booster and the hydraulic block can be made about him regardless of the absolute screwing or the angle of rotation, which has covered the coupling portion when screwed into the hydraulic block.

The other hole 109 goes into the of the Fig. 1 to 5 shown tank or reflux line 9 via. It is where it actually opens into the free end of the coupling portion 101, closed by a plug 110. It is blended with a transverse bore 111, which opens into an annular groove 112. The annular groove 112 is located in said further fluid transfer region 105. In this way, the external tank connection 6 is represented.

As a result of its equipment with the annular groove 112 and the fluid transfer region 104 is designed so that irrespective of the absolute screwing or the angle of rotation, which has covered the coupling portion 101 when screwing into the hydraulic block 100, a fluid-conducting connection between the pressure booster and the hydraulic block can be produced.

It should also be noted that the fluid transfer region 105 can alternatively be designed in accordance with how the fluid transfer region 104, that is to say can lie on the peripheral circumferential surface of the coupling section. However, such an embodiment is not preferred.

It is particularly expedient to provide the section of the cylinder block 13 located outside the hydraulic block 100 with a coupling section for a screwing tool, preferably in the form of an external hexagon - which, however, is not shown in the drawing.

The external high-pressure port 7 is located in this embodiment, preferably on the side facing away from the coupling portion 101 side of the booster 1. Here is carried out in a conventional manner a fluid-conducting connection to the high-pressure consumer.

The FIGS. 8 and 9 show a second concrete embodiment of the pressure intensifier according to the invention. The preceding statements for the first embodiment also apply here, unless otherwise described below.

Here, the coupling portion is formed by the predominant part of the circumferential surface of the cylinder block 13. Preferably, the cylinder block 13 of the booster 1 is designed so that it can be at least ½, better 2/3 of the length that the cylinder block 13 has in the direction of its longitudinal axis L, inserted into a bore of the hydraulic block 100. In the specific case, the cylinder block is designed so that the first and the second cylinder block element 13.1 and 13.2 can be completely inserted into the hydraulic block 100. The highly loaded area of the pressure intensifier, in which the differential piston moves back and forth, now lies completely in the hydraulic block, from which a stiffness-increasing support effect emanates. As can be seen, the coupling portion 101 is again designed so that it can completely enclose the receiving bore of the hydraulic block 100 at its periphery and at its free end face.

Again, the diameter of the coupling portion preferably corresponds to the core diameter of a metric thread and is reduced in relation thereto by a degree of tolerance which allows the non-male threaded portion of the coupling portion to pass through the female threaded portion of the hydraulic block.

At the coupling portion 101, three fluid transfer regions 104, 105 and 113 are formed in this embodiment. They are seen in the direction of the longitudinal axis L of the booster one behind the other and seen in the screwing of the coupling portion, if necessary, before the provided with an external thread portion of the coupling portion.

Via these fluid transfer areas 104, 105 and 113 (and only via these), the pressure booster 1 communicates directly to the outside, d. H. with the hydraulic block. An additional hose or pipe connection for connection to the high pressure consumer is not provided here, the high pressure consumer is powered by the pressure booster 1 via the hydraulic block 100.

The first fluid transfer region 104 is bounded on both sides by seals 114, which are preferably cord seals inserted with or without a support ring in a peripheral annular groove on the coupling portion 101.

The in Fig. 8 low-pressure line section 8 opens into a transverse bore which opens on its other side into the outer surface of the cylinder block or (where present) of the second cylinder block element 13.2, within the first fluid transfer region 104. As a result, the external low-pressure connection 5 is formed. Preferably carries the Cylinder block 13 in this area for reasons of strength, no annular groove, but is smooth and thus unimpaired. The corresponding annular groove is here instead preferably mounted in the hydraulic block 100.

In the Fig. 8 The "tank line" shown is preferably extended by a bore extending within the cylinder block 13 into the region of the front shoulder 116 of the coupling section 101, where it discharges, into the second fluid transfer region 105. The external tank connection 6 is thereby represented. Preferably, the second fluid transfer region is limited in the direction of the outside of the hydraulic block by a further seal 118 and thereby kept small, wherein the seal is preferably also in a circumferential annular groove of the coupling portion and the seals 114, 115 may correspond.

The front shoulder 116 is formed by the fact that the coupling section tapers here.

The tapered cylinder extension 117 of the coupling portion 101 is designed so that it can be inserted into a second, tapered portion of the here designed as a stepped bore in the hydraulic block 100 receiving bore. The tapered cylinder extension 117 carries at least one, better two circumferential annular grooves in which - usually with support rings - one or two seals 119 are inserted. These one or two seals seal the third fluid transfer region 113 from the second fluid transfer region 105. The third fluid transfer region is thus formed at the free end end of the coupling portion 101. In the free end, the high-pressure line opens, so that here the external high-pressure port 7 is formed.

Said rejuvenation of the cylinder extension 117 takes place with consideration for the high pressure present there. This preferably makes it necessary to keep the lengths to be sealed small and also to keep the surfaces exposed to the high-pressure action and thus the forces arising therefrom small.

Independent protection is also claimed for a pressure intensifier cascade comprising a hydraulic block 100 and a plurality of pressure amplifiers 1 connected in series in series, characterized in that the pressure intensifiers 1 mounted side by side on the hydraulic block 100 are those according to one of the preceding claims.

LIST OF REFERENCE NUMBERS

1

booster

2

Intensifier piston

3

spool

3.1

Control sleeve of the control piston

3.2

damping piston

4.1

check valve

4.2

check valve

4.3

controllable non-return valve

5

Connection of external low pressure (low pressure connection)

6

Connection of external tank (tank connection)

7

Connection of external high pressure consumers (high pressure connection)

8th

Low-pressure line

8.1

Low-pressure line section to the high-pressure working space

8.2

Low pressure line section to the high pressure consumer

8.3

Low pressure line section for continuous bias of the control piston

8.4

Low pressure line section to allow the control piston, the forwarding of low-pressure working fluid

8.5

control line

9

Tank or return line

9.1

Return line section to the high pressure consumer

9.2

Return line section to the control piston

10

Low pressure working space

11

High-pressure working space

12

gap

13

cylinder block

13.1

first cylinder block element

13.2

second cylinder block element

13.3

third cylinder block element

14

Connecting line from the control piston to the pressure intensifier piston

15 to 24

not forgiven

24 *

Bypass throttle

25

switching valve

26

external low pressure feed pump

27

not forgiven until 99

100

hydraulic block

101

coupling section

102

Thread of the coupling section

103

Thread of the coupling section

104

first fluid transfer area

105

second fluid transfer area

106

poetry

107

poetry

108

drilling

109

drilling

110

Plug

111

cross hole

112

ring groove

113

third fluid transfer area

114

poetry

115

poetry

116

Fronto

117

Cylindrical extension

118

another seal

119

another seal

L

Longitudinal axis of the booster or its cylinder block

H

High pressure piston

N

Low-pressure piston

S

piston shaft

DH

Diameter high-pressure piston

DN

Diameter low pressure piston

V1

first slimmed-down area of the control piston

V2

second slimmed-down area of the control piston

DW

Wall thickness of the clamping sleeve in the radial direction

D

inner diameter of the adapter sleeve

Claims (13)

1. A pressure intensifier (1) for fluids, in particular for liquids, comprising a cylinder block (13) in which a pressure intensifier piston (2) and a control piston (3) move cyclically, wherein the pressure intensifier piston (2) forms a high-pressure working chamber (11) and a low-pressure working chamber (10) in the cylinder block (13) and the cylinder block (13) has a low-pressure connection (5) for feeding in low-pressure fluid from outside, a high-pressure connection (7) for discharging higher-pressure working fluid towards the outside and a connection for discharging fluid whose working capacity in the pressure intensifier (1) is exhausted, characterized in that the cylinder block (13) has a coupling portion (101) rigidly connected with it, which can be inserted into a receiving bore of a hydraulic block (100) and fixed there, so that the receiving bore encloses the coupling portion (101), wherein the coupling portion (101) has at least two fluid transfer regions (104, 105, 113) fluidically separated by a seal, for exchanging fluid between the pressure intensifier (1) and the hydraulic block (100) into which it is inserted.
2. The pressure intensifier (1) according to claim 1, characterized in that (coming from inside the cylinder block (13)), a channel, via which the pressure intensifier (1) discharges fluid in operation whose working capacity is exhausted, leads into a fluid transfer region (104, 105, 113), and that a further channel, via which low-pressure fluid is fed into the pressure intensifier (1), leads into another fluid transfer region (104, 105, 113).
3. The pressure intensifier (1) according to claim 1 or 2, characterized in that the coupling portion (101) has a third fluid transfer region (113) for transferring the higher-pressure working fluid to the hydraulic block (100).
4. The pressure intensifier (1) according to any one of the preceding claims, characterized in that at least one of the fluid transfer regions (104, 105, 113) comprises a peripheral annular groove (112).
5. The pressure intensifier (1) according to any one of the preceding claims, characterized in that at least one channel leads into the end face (entire end or end surface of an annular shoulder) of the coupling portion (101), ideally the channel via which the higher-pressure working fluid is discharged by the pressure intensifier (1).
6. The pressure intensifier (1) according to any one of the preceding claims, characterized in that the coupling portion (101) has a thread (102) for screwing the coupling portion (101) into a hydraulic block (100).
7. The pressure intensifier (1) according to claim 6, characterized in that the fluid transfer regions (104, 105, 113) are disposed between the free end of the coupling portion (101) to be inserted into the hydraulic block (100) and the thread (102) of the coupling portion (101).
8. The pressure intensifier (1) according to any one of the preceding claims, characterized in that the cylinder block (13) of the pressure intensifier (1) has a molded-on hexagon.
9. The pressure intensifier (1) according to any one of the preceding claims, characterized in that at least two bores (108, 109) extending parallel to the longitudinal axis (L) of the pressure intensifier (1) run through coupling portion (101), which extend from the free end face of the coupling portion (101) into the area of the cylinder block (13), which is always positioned outside the hydraulic block (100) accommodating the coupling portion (101).
10. The pressure intensifier (1) according to claim 9, characterized in that the end leading into the free end face of the coupling portion (101) is sealed by a plug (110) at at least one of the bores (108, 109), and that this bore (108, 109) intersects a cross bore (111) that leads into a fluid transfer region (104).
11. A hydraulic unit comprising a hydraulic block (100) in which several bores, through which hydraulic fluid flows, for connecting different hydraulic operative units are formed, and at least one pressure intensifier (1) according to any one of the preceding claims, characterized in that the pressure intensifier (1) has a coupling portion (101) inserted into a bore in the hydraulic block (100).
12. The hydraulic unit according to claim 11, characterized in that the hydraulic unit comprises several pressure intensifiers (1) according to any one of the claims 1 to 11, each of which has a coupling portion (101) inserted into a bore of the hydraulic block (100).
13. The hydraulic unit according to claim 12, characterized in that at least two, better at least three, pressure intensifiers (1) are connected in series one behind the other, so that the high pressure provided by a pressure intensifier (1) preceding in the flow direction constitutes the pressure with which a subsequent pressure intensifier (1) in the flow direction is supplied on the input side.

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