EP4168673A1

EP4168673A1 - Reciprocating piston pump for conveying a medium

Info

Publication number: EP4168673A1
Application number: EP21733091.9A
Authority: EP
Inventors: Katharina SCHRANK; Florian SCHOEMAKER; Dirk Schulze Schencking
Original assignee: Hauhinco Maschinenfabrik G Hausherr Jochums GmbH and Co KG
Current assignee: Hauhinco Maschinenfabrik G Hausherr Jochums GmbH and Co KG
Priority date: 2020-06-19
Filing date: 2021-06-10
Publication date: 2023-04-26
Also published as: DE102020116294A1; WO2021254869A1; AU2021292365A1; CN115956160A

Abstract

A reciprocating piston pump (1) is described for conveying a medium with a pumping module (2) with a cylinder head (6), a cylinder (7) and a reciprocating piston (8), and with a drive (3), wherein the reciprocating piston (8) has a reciprocating piston head (13) with a reciprocating piston head surface (14), wherein the cylinder head (6), the cylinder (7) and the reciprocating piston head (13) form a conveying chamber (35), wherein the reciprocating piston (8) is configured to convert a drive movement (32) into a conveying reciprocating movement (37), and wherein the cylinder head (6), the cylinder (7) and the reciprocating piston (8) are configured to convert the conveying reciprocating movement (37) into conveying of a medium. A problem of the present invention is specification of a reciprocating piston pump (1) with a media separation means. The problem is achieved by virtue of the fact that the reciprocating piston pump (1) has an auxiliary reciprocating piston (9), that the auxiliary reciprocating piston (9) is arranged between the drive (3) and the reciprocating piston (8), and has an auxiliary reciprocating piston head (17) with an auxiliary reciprocating piston head surface (18), that the cylinder (7), the reciprocating piston (8) and the auxiliary reciprocating piston head (17) form a lubricating volume (36), that the cylinder (7), the reciprocating piston (8) and the auxiliary reciprocating piston (9) are configured to convert the drive movement (32) into an auxiliary conveying reciprocating movement (33) of the auxiliary reciprocating piston (9) and to convert the latter via a lubricating medium in the lubricating volume into the conveying reciprocating movement (37), and that the auxiliary reciprocating piston head surface (18) is smaller than the reciprocating piston head surface (14).

Description

Reciprocating piston pump for pumping a medium

The invention relates to a reciprocating piston pump for conveying a medium. The reciprocating piston pump has, on the one hand, at least one pump module and, on the other hand, a drive. The drive is designed to drive the at least one pump module so that the at least one pump module conveys a medium during operation.

The reciprocating piston pump is used to supply devices with power, the power being transmitted via a medium that is pressurized by the reciprocating pump during delivery. During operation, the reciprocating piston pump generates a pressure in the medium of more than 160 bar. The reciprocating piston pump and the devices to be supplied are connected, for example, to a hydraulic circuit to transmit the power.

The at least one pump module has a cylinder head, a cylinder and a reciprocating piston, the reciprocating piston having a reciprocating piston base with a reciprocating piston base surface. The cylinder head, the cylinder and the piston base form a delivery volume. In other words, to close the cylinder head, the cylinder and the reciprocating piston base, the volume of the För.

The reciprocating piston is designed to convert a drive movement of the drive into a delivery stroke movement and a suction stroke movement of the reciprocating piston in the cylinder along a longitudinal axis. Accordingly, the delivery volume is not constant: The delivery volume is reduced when the stroke piston approaches the cylinder head during the delivery stroke movement. At the same time, a pressure rises in a medium that is in the delivery volume. The delivery volume is increased when the reciprocating piston moves away from the cylinder head during the suction stroke. At the same time, the pressure in a medium in the delivery volume drops.

The cylinder head, the cylinder and the reciprocating piston are designed to implement the För derhubbewegung in a promotion of a medium from the delivery volume by reducing the delivery volume. Usually they are also designed to convert the suction stroke into a suction of a Implement the medium in the delivery volume by increasing the delivery volume.

The design of the cylinder head includes, for example, a cylinder head control, which ensures an inflow of a medium into the delivery volume during the suction stroke movement and an outflow of a medium from the delivery volume during the delivery stroke movement. For this purpose, the cylinder head control has, for example, an inflow valve and an outflow valve. The design of the cylinder and reciprocating piston includes, for example, that these are sealed with one another, so that during the delivery stroke movement a pressure in a medium in the delivery volume rises and falls during the suction stroke movement.

The reciprocating piston pump is intended for pumping media that have a lower viscosity than lubricating media. Such media are, for example, HFA and HFC media, water-glycol mixtures and also water. It is therefore also intended to convey media that are corrosive. It is also intended to convey media with particles, i.e. media that are abrasive.

Next, the reciprocating piston pump is intended to generate pressures during the delivery stroke movement, in which media are no longer suitable for lubricating contact surfaces between the cylinder and reciprocating piston and bearings in the drive. Such pressures are, for example, more than 150 bar.

Due to the media and the pressures, these contact surfaces and bearings have to be lubricated with a lubricant that differs from the media, and a media separation between the media on the one hand and the lubricant on the other hand must be implemented. The media separation must ensure that the medium does not leak into the lubricating medium. Leakage of the medium into the lubricating medium leads to a deterioration in the lubricating properties of the lubricating medium, as a result of which the lubrication of the contact surfaces and the bearings is no longer guaranteed and the contact surfaces and the bearings are damaged. Conversely, a slight leakage of the lubricating medium into the medium can be tolerated.

Various implementations of media separation are known from the prior art. The media separation is implemented using a stuffing box seal between the reciprocating piston and the cylinder. In order for the stuffing box seal to seal the cylinder and the reciprocating piston sufficiently tightly, the stuffing box seal must be saturated with the medium. However, ensuring that the medium is saturated also inevitably leads to leakage of the medium into the lubricating medium, so that the lubricating medium has to be replaced at intervals according to the concentration of the medium in the lubricating medium. Another disadvantage is that a sealing surface of the stuffing box seal is large and requires correspondingly high frictional forces that have to be applied by the drive. Furthermore, the sealing surface cannot be checked.

Another implementation uses an elastomeric seal. In order to reduce wear on the elastomer seal, it must be cooled. The medium is used for this purpose, but this requires a small amount of leakage past the elastomer seal. Thus, even when using an elastomer seal, the medium penetrates the lubricating medium. Next, a frequency of the delivery stroke and suction stroke movement is limited to a maximum frequency due to viscoelastic properties of the elastomer seal. In a further implementation, the reciprocating piston and the delivery volume are separated from one another by a membrane. The delivery volume is formed here by the cylinder head, the cylinder and the membrane. This implementation ensures complete media separation, which is why there is no leakage. The membrane follows the delivery stroke and suction stroke movement of the reciprocating piston. However, the diaphragm rubs against the piston and cylinder, causing it to wear out and eventually having to be replaced.

The object of the present invention is to provide a reciprocating piston pump with media separation which at least reduces the disadvantages from the prior art. The object is achieved by a reciprocating piston pump with the features of Pa tentans claim 1.

The reciprocating piston pump has an auxiliary reciprocating piston. The auxiliary lifting piston is arranged between the drive and the lifting piston and has an auxiliary lifting piston base with an auxiliary lifting piston base surface. The cylinder, the reciprocating piston and the auxiliary reciprocating piston base form a lubricating volume for a lubricating medium for lubricating contact surfaces between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston on the other. In other words, the cylinder, the reciprocating piston and the auxiliary reciprocating piston base enclose the lubricating volume.

The cylinder, the reciprocating piston and the auxiliary lifting piston are designed to convert the drive movement into an auxiliary conveying stroke movement and an auxiliary suction stroke movement of the auxiliary lifting piston in the cylinder along the longitudinal axis and the auxiliary conveying stroke movement of the auxiliary lifting piston into the conveying stroke movement of the reciprocating piston via a lubricant in the lubricating volume.

Because the lubrication volume is formed not only by the cylinder but also by the reciprocating piston and the auxiliary reciprocating piston base, a lubricating medium is in direct contact with the cylinder. Due to the delivery and suction stroke movement of the reciprocating piston and the auxiliary delivery and suction stroke movement of the auxiliary piston, both the reciprocating piston and the auxiliary reciprocating piston move over sections of the cylinder that were previously in direct contact with a lubricating medium, whereby the contact surfaces between on the one hand the The cylinder and the reciprocating piston and, on the other hand, the cylinder and the auxiliary reciprocating piston are lubricated with the lubricating medium.

The base area of the auxiliary reciprocating piston is smaller than the base area of the reciprocating piston, so that during the auxiliary conveying stroke movement a pressure of a lubricating medium in the lubricating volume is greater than a pressure of a medium in the conveying volume. In other words, the pressure in the lubricating medium is greater than the pressure in the medium because the auxiliary lifting piston base area is smaller than the lifting piston base area.

Because the pressure in the lubricant in the lubricant volume is greater than the pressure in the medium in the delivery volume, a leak only occurs from the lubricant volume on the one hand into the delivery volume and on the other in the direction of the drive Leakage in the delivery volume tolerable. In any case, no medium penetrates the lubricant, so that the lubricating properties of the lubricant do not deteriorate. In comparison with the first two implementations of media separation described, there is no longer any leakage of the medium into the lubricating medium. The frictional power is also reduced in comparison with the first implementation and the maximum frequency is higher in comparison with the second implementation. Compared to the third implementation of media separation, wear is reduced and the maintenance intervals are therefore longer.

In one embodiment of the reciprocating piston pump it is provided that the cylinder has a cylinder inner jacket surface concentric to the longitudinal axis with a cylinder radius, that the reciprocating piston has a reciprocating piston outer jacket surface concentric to the longitudinal axis with a reciprocating piston radius and that the auxiliary piston has an auxiliary reciprocating piston outer circumferential surface concentric to the longitudinal axis and having an auxiliary reciprocating piston radius. It is further provided that both the reciprocating piston radius and the auxiliary reciprocating piston radius match the cylinder radius. For example, the cylinder radius has a first value over a first distance along the longitudinal axis and a second value over a second distance along the longitudinal axis, which is smaller than the first value. Then the reciprocating piston radius has a value matching the first value and the auxiliary reciprocating piston radius has a value matching the second value. The first path extends over the delivery and suction stroke movement of the reciprocating piston and the second path extends over the auxiliary delivery and auxiliary suction stroke movement of the auxiliary stroke piston.

However, the reciprocating piston radius and the auxiliary reciprocating piston radius are preferably the same. Then the cylinder radius has the same value over the first and second distance and the reciprocating piston radius and the auxiliary lifting piston radius have a value that matches the value.

If the auxiliary conveying stroke movement of the auxiliary lifting piston is converted into the conveying stroke movement of the reciprocating piston via a lubricating medium in the lubricating volume, then a pressure in the lubricating medium in the lubricating volume is higher than a pressure in the medium in the conveying volume. This is achieved by the fact that the auxiliary piston base area is smaller than the piston base area. A reduction in the auxiliary lifting piston base area compared to the lifting piston base area is implemented in a further embodiment in that the lifting piston is a relief piston and the auxiliary lifting piston in the auxiliary lifting piston base is a relief cylinder to match Has relief piston and in that the relief cylinder has a relief s volume and / or is verbun with a relief s volume. The relief piston is preferably a shaft.

Since a very small leakage between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston cannot be avoided, the lubricant volume decreases, which is why a piston distance between the reciprocating piston and the auxiliary reciprocating piston is smaller and the auxiliary delivery stroke movement is greater than the delivery stroke movement. The reduction in the distance between the pistons causes the relief piston to move into the relief cylinder. This increases the pressure in the relief volume. The relief volume is formed, for example, by the relief piston and the relief cylinder. This increase in pressure counteracts the reduction in the size of the auxiliary piston base area compared to the piston base area. It is therefore advantageous to choose the relief volume as large as possible. The relief volume is preferably the environment, so that there is practically no increase in pressure in the relief volume. For this purpose, the auxiliary lifting piston has a relief line which connects the relief cylinder with the environment.

In a further development of the above embodiment it is provided that the relief stroke piston and the relief cylinder limit a piston distance between the reciprocating piston and the auxiliary lifting piston along the longitudinal axis to a maximum piston distance. Limiting the distance between the pistons means that the volume of lubricant is also limited to a maximum volume of lubricant. Without limiting the distance between the pistons, there is a possibility that the reciprocating piston will hit the cylinder head during the delivery stroke movement and the reciprocating piston pump will be damaged.

In a further embodiment it is provided that the reciprocating piston pump has a bearing and that the bearing is arranged between the drive and the auxiliary reciprocating piston. Furthermore, the bearing is designed to convert the drive movement of the drive into the auxiliary conveying stroke movement and into the auxiliary suction stroke movement of the auxiliary lifting piston.

In a further development of the above embodiment it is provided that the drive has a drive shaft. It is also provided that the drive shaft has a drive with an eccentric sliding surface and the auxiliary lifting piston has an auxiliary lifting piston sliding surface. The Eccentric sliding surface and the auxiliary lifting piston sliding surface the bearing. Next, the drive shaft and the auxiliary lifting piston are designed to convert the drive movement of the drive shaft in the form of a rotation via the bearing into the auxiliary conveying stroke movement and into the auxiliary suction stroke movement. The drive shaft without drive eccentric is designed as a crankshaft with a crank pin, the crank pin being rotatably arranged in the drive eccentric center. A rotary movement of the drive eccentric is prevented by an eccentric shape of the eccentric sliding surface in connection with the auxiliary lifting piston sliding surface. An alternative to this is a drive shaft with an eccentric pin, the eccentric pin being rotatably arranged in the drive in a sex center manner.

The eccentric sliding surface and the auxiliary lifting piston sliding surface have a common contact surface via which the rotation of the drive shaft is converted into the auxiliary conveying and auxiliary suction stroke movement. In this sense, the eccentric and the auxiliary piston sliding surface form the bearing. The common contact surface must be lubricated with a lubricant in order to reduce wear on the eccentric and auxiliary piston sliding surfaces. The bearing is designed for a lubricating medium which is also suitable for the contact surfaces between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston on the other.

If the reciprocating piston pump has the bearing described above, then a sufficient supply of the bearing with a lubricant must be guaranteed. Therefore, in a further embodiment it is provided that the auxiliary lifting piston has an auxiliary lifting piston lubrication line that the auxiliary lifting piston lubrication line connects the lubricating volume and the auxiliary lifting piston ben sliding surface for supplying the bearing with a lubricating medium. Accordingly, the bearing is lubricated with the lubricating medium with which the contact surfaces between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston on the other hand are lubricated. In this case, the bearing is supplied with a lubricating medium at a pressure that is established in the delivery volume during the delivery stroke movement. The auxiliary piston lubricant line is preferably a channel in the auxiliary piston. Then there is no separate lubricant line.

In a further development of the above embodiment it is provided that the auxiliary reciprocating piston lubrication line has at least one check valve shows. The check valve prevents a lubricant in the bearing from running off. The drainage would occur without the check valve, for example during the suction stroke movement.

In a further embodiment, the reciprocating piston pump has a longitudinal slide valve for controlling the supply of a lubricating medium into the lubricating volume. The longitudinal slide valve has at least one cylinder opening in the cylinder for supplying a lubricating medium into the lubricating volume Groove, pocket and / or hole. The function of a valve results inherently either through the delivery and suction stroke movement of the Hubkol ben or through the auxiliary delivery and auxiliary suction stroke movement of the auxiliary piston past the at least one cylinder opening in the cylinder.

In a particularly preferred development of the above Ausgestal device, the auxiliary piston lubrication line described above is also implemented. In this development, not only are the contact surfaces between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston on the other hand, but also the bearing is lubricated with a lubricating medium that can be supplied via the longitudinal slide valve.

In a further development of the above embodiment it is provided that the at least one cylinder opening releases a supply of a lubricating medium to the lubricating volume when the reciprocating piston is in the area of a reversal point from the suction stroke movement to the delivery stroke movement. In the area of the reversal point, the pressure in the lubricating volume is lowest, so that the supply of a lubricating medium is most effective.

If the reciprocating piston pump has the bearing described above, then a sufficient supply of the bearing with a lubricant must be guaranteed. As an alternative or in addition to the previously described configuration with the auxiliary reciprocating piston lubrication line, the following configuration provides that the drive shaft has a drive lubrication line. The drive lubrication line accordingly extends both through the drive shaft itself and through the drive shaft sixth. The drive shaft also has a rotary slide valve for controlling the supply of a lubricating medium to the bearing. The rotary slide valve has a drive shaft recess in the drive shaft via a Angular range of a rotation of the drive shaft, so that a supply of a lubricant into the bearing it follows only over the angular range. The drive lubrication line is preferably a channel in the drive shaft and in the drive eccentric. Then there is no separate lubricant line. The rotary slide valve is usually formed by the drive shaft recess and the drive lubrication line in the eccentric. The rotary slide valve also ensures that a lubricant is supplied to the contact surfaces between the drive shaft and the drive eccentric. In a further development of the above embodiment, it is provided that the drive lubrication line has at least one check valve. The check valve prevents a lubricant in the bearing from running off.

In a particularly preferred development of the above embodiment, the auxiliary piston lubrication line described above is also implemented. In this development, not only the bearing but also the contact surfaces between the cylinder on the one hand and the reciprocating piston and the auxiliary reciprocating piston on the other hand are lubricated with a lubricating medium that can be supplied via the drive lubrication line. In a further embodiment, the reciprocating piston pump has a lubricating pump for supplying the at least one pump module and / or the drive with a lubricating medium. The reciprocating piston pump in configurations with the previously described longitudinal slide valve is designed to supply a lubricant from the lubricant pump to the longitudinal slide valve and in configurations with the above-described drive lubricant line to supply a lubricant from the lubricant pump to the drive lubricant line.

In detail, there is a multitude of options for designing and developing the reciprocating piston pump. For this purpose, reference is made both to the claims subordinate to claim 1 and to the following description of exemplary embodiments in conjunction with the drawing. In the drawing shows

Lig. 1 an abstract perspective sectional illustration of a first exemplary embodiment of a reciprocating piston pump, 2 shows an abstract perspective illustration of a cylinder of the first exemplary embodiment,

3 shows an abstract perspective representation of a reciprocating piston of the first exemplary embodiment, FIGS. 4a, 4b two different abstract perspective representations of an auxiliary reciprocating piston of the first exemplary embodiment,

5 shows an abstract perspective sectional illustration of a second exemplary embodiment of a reciprocating piston pump and

Fig. 6 is a perspective view of a third game Ausführungsbei a reciprocating pump.

1 shows a first exemplary embodiment of a reciprocating piston pump 1 for conveying a medium. It has a pump module 2, a drive 3, a bearing 4 and a lubrication pump 5.

The pump module 2 has a cylinder head 6, a cylinder 7, see also FIG. 2, a reciprocating piston 8, see also FIG. 3, and an auxiliary reciprocating piston 9, see also FIGS. 4a, 4b.

The cylinder 7 has a cylinder inner jacket surface 11 which is concentric to a longitudinal axis 10 and has a cylinder radius 12. The reciprocating piston 8 has a reciprocating piston bottom 13 with a reciprocating piston bottom surface 14 and a reciprocating piston outer jacket surface 15 concentric to the longitudinal axis 10 with a reciprocating piston radius 16. The auxiliary lifting piston 9 is arranged between the drive 3 and the lifting piston 8, has an auxiliary lifting piston floor 17 with an auxiliary lifting piston bottom surface 18, an auxiliary lifting piston outer surface 19 concentric to the longitudinal axis 10 with an auxiliary lifting piston radius 20 and an auxiliary lifting piston sliding surface 21 . The reciprocating piston radius 16 and the auxiliary reciprocating piston radius 20 are the same and match the cylinder radius 12.

The reciprocating piston 8 has a relief stroke piston 22 and the auxiliary stroke piston 9 in the auxiliary stroke piston base 17 has a relief cylinder 23 that matches the relief stroke piston 22. The relief cylinder 23 is connected to the environment as a relief volume via a relief line 24. In this exemplary embodiment, the relief piston 22 is a shaft. The relief piston 22 and the relief cylinder 23 limit a piston distance 25 between the reciprocating piston 8 and the auxiliary piston 9 along the longitudinal axis 10 to a maximum piston distance. For this purpose, the relief piston 22 has a ring 26 and the relief cylinder 23 has a groove 27 matching the ring 26. The reciprocating piston 8 and the auxiliary stroke piston 9 can be moved relative to one another along the longitudinal axis 10 according to the ring 26 and the groove 7.

The drive 3 has a drive shaft 28 and the drive shaft 28 has a drive eccentric 29 with an eccentric sliding surface 30. The drive shaft 28 without drive eccentric 29 is designed as a crankshaft with a crank pin 31, the crank pin 31 being rotatably arranged in the drive eccentric 29. A rotational movement of the drive eccentric 29 is prevented by an ex-centric shape of the eccentric sliding surface 30 in connection with the Auflie lowing auxiliary lifting piston sliding surface 21. The eccentric sliding surface 30 and the auxiliary lifting piston sliding surface 21 form the bearing 4. The bearing 4 is arranged between the drive 3 and the auxiliary lifting piston 9. The drive shaft 28 with the drive 29 and the auxiliary lifting piston 9 are formed, a drive movement 32 of the drive shaft 28 in the form of a rotation via the bearing 4 into an auxiliary conveying lifting movement 33 and into an auxiliary suction lifting movement 34 of the auxiliary lifting piston 9 in the cylinder 7 along the longitudinal axis 10 to implement. The bearing 4 is thus designed to convert the drive movement 32 into the auxiliary conveying stroke movement 33 and into the auxiliary suction stroke movement 34.

The cylinder head 6, the cylinder 7 and the reciprocating piston bottom 9 form a delivery volume 35. The cylinder 7, the reciprocating piston 8 and the auxiliary reciprocating piston bottom 17 also form a lubricating volume 36 for a lubricating medium for lubricating contact surfaces between the cylinder 7 on the one hand and the other the reciprocating piston 8 and the auxiliary reciprocating piston 9. The contact surfaces in this exemplary embodiment are, on the one hand, the cylinder inner jacket surface 11 and the reciprocating piston outer jacket surface 15 and, on the other hand, the cylinder inner jacket surface 11 and the auxiliary reciprocating piston outer jacket surface 19.

The cylinder 7, the reciprocating piston 8 and the auxiliary lifting piston 9 are designed to convert the drive movement 32 into the auxiliary conveying stroke movement 33 and into the auxiliary suction stroke movement 34 of the auxiliary piston 9 in the cylinder 7 along the longitudinal axis 10 and also the auxiliary conveying stroke movement 33 of the Auxiliary lifting piston 9 via a lubricant in the lubricating volume 36 into a delivery stroke movement 37 of the reciprocating piston 8 in the cylinder 7 along the longitudinal axis 10. In the present embodiment, the cylinder 7, the reciprocating piston 8 and the auxiliary lifting piston 9 are also designed to convert the auxiliary suction stroke movement 34 of the auxiliary piston 9 into a suction stroke movement 3 of the stroke piston 8 in the cylinder 7 along the longitudinal axis 10 via a lubricant in the lubricating volume 36.

In this respect, the reciprocating piston 8 is designed to convert the drive movement 32 of the drive 3 into the delivery stroke movement 37 and into the suction stroke movement 38 of the reciprocating piston 8 in the cylinder 7 along the longitudinal axis 10.

The cylinder head 6, the cylinder 7 and the reciprocating piston 8 are designed to convert the delivery stroke movement 37 of the reciprocating piston 8 into a delivery of a medium from the delivery volume 35 by reducing the delivery volume 35. For this purpose, the cylinder head 6 has a cylinder head control which ensures that a medium flows into the delivery volume 35 during the suction stroke movement 38 and that a medium flows out of the delivery volume 35 during the delivery stroke movement 37. For this purpose, the cylinder head control has an inflow valve and an outflow valve. Neither the cylinder head control nor the inflow and outflow valve are shown. The cylinder head 6, the cylinder 7 and the reciprocating piston 8 are also designed in this exemplary embodiment to convert the suction stroke movement 38 into a suction of a medium into the delivery volume 35 by increasing the delivery volume 35.

The auxiliary reciprocating piston bottom surface 18 is smaller than the reciprocating piston bottom surface 14, since the auxiliary reciprocating piston bottom surface 18, in contrast to the reciprocating piston bottom surface 14, lacks a cross-sectional area of the relief cylinder 23. As a result, during the auxiliary delivery stroke movement 33 of the auxiliary stroke piston 9, a pressure of a lubricant in the lubricant volume 36 is greater than a pressure of a medium in the delivery volume 35 that results from the delivery stroke movement 37 of the reciprocating piston 8.

The auxiliary lifting piston 9 has an auxiliary lifting piston lubrication line 39. The auxiliary lifting piston lubrication line 39 connects the lubricating volume 36 and the auxiliary lifting piston sliding surface 21 to one another to supply the bearing 4 with a lubricating medium. The auxiliary lifting piston lubrication line 39 is a channel in the auxiliary lifting piston 9. The drive eccentric 29 preferably has an auxiliary lubrication line, which the eccentric sliding surface 30 with con contact surfaces between the crank pin 31 and the drive eccentric 29 ver binds, so that these contact surfaces are also supplied with a lubricating medium during operation. However, this auxiliary lubrication line is not shown here. The reciprocating piston pump 1 also has a longitudinal slide valve 40 for controlling the supply of a lubricating medium into the lubricating volume 36. The longitudinal slide valve 40 has a cylinder opening 41 in the cylinder 7 for feeding a lubricating medium into the lubricating volume 36. The cylinder opening 41 is a bore. The cylinder opening releases the supply line of a lubricating medium into the lubricating volume 36 when the reciprocating piston 8 is in the region of a reversal point from the suction stroke movement 38 to the delivery stroke movement 37.

The lubrication pump 5 is designed to supply the pump module 2 and the drive 3 with a lubricating medium, and the reciprocating piston pump 1 is designed to supply a lubricating medium from the lubricating pump 5 to the longitudinal slide valve 40. Through the auxiliary reciprocating piston lubrication line 39 not only the Kontaktflä surfaces between the cylinder 7 on the one hand and the reciprocating piston 8 and the auxiliary reciprocating piston 9, but also the bearing 4 is supplied with a lubricant for lubrication during operation of the reciprocating piston pump 1. The supply of the bearing 4 follows from the lubricating volume 36 via the auxiliary piston lubricating line 39.

5 shows a second exemplary embodiment of a reciprocating piston pump 1 for conveying a medium. Only the differences from the first exemplary embodiment are described below. Otherwise, the statements about the first apply analogously to the second exemplary embodiment.

In contrast to the first exemplary embodiment, the reciprocating piston pump 1 does not have the longitudinal slide valve 40 described in the second exemplary embodiment. Instead, the drive shaft 28 has a drive lubrication line 42. The drive lubrication line 42 accordingly extends through the drive shaft 28 itself as well as through the drive eccentric 29. The part of the drive lubrication line 42 in the drive eccentric 29 corresponds to that of the auxiliary lubrication line in the first embodiment.

The drive shaft 28 also has a rotary slide valve 43 for controlling the supply of a lubricating medium to the bearing 4. The rotary slide valve 43 has a drive shaft recess 44 in the drive shaft 28 over an angular range of a rotation of the drive shaft 28, as a result of which a lubricant is fed into the bearing 4 only over the angular range. In this embodiment, the drive lubrication line 42 is a channel in the drive shaft 28 and in the drive 29. The rotary slide valve 43 is formed by the drive shaft recess 44 and the drive lubrication line 42 in the eccentric 29. The rotary slide valve 43 also ensures a supply of lubricant to contact surfaces between the drive shaft 28 and the drive eccentric 29. The lubricating pump 5 is designed to supply the pump module 2 and the drive 3 with a lubricating medium and the reciprocating piston pump 1 is designed to supply a lubricating medium from the lubricating pump 5 designed for the drive lubrication line 42. Through the drive lubrication line 42 and the auxiliary piston lubrication line 39, when the reciprocating pump 1 is in operation, not only is the bearing 4, but also the contact surfaces between the cylinder 7 on the one hand and the reciprocating piston 8 and the auxiliary reciprocating piston 9 with a lubricant for lubrication on the other provided. The supply of the contact surfaces between the cylinder 7 on the one hand and the reciprocating piston 8 and the auxiliary reciprocating piston 9 on the other hand and also the supply of the lubricating volume 36 with a lubricating medium take place via the auxiliary reciprocating piston lubrication line 39 and the bearing 4 from the drive lubrication line 42.

Lig. 6 shows a third exemplary embodiment of a reciprocating piston pump 1. In contrast to the first and second exemplary embodiments, it has a plurality of pump modules 2. Otherwise, the reciprocating piston pump 1 is designed like the reciprocating piston pump described in the first or second exemplary embodiment.

Reference number

1 reciprocating piston pump

2 pump module

3 drive 4 bearings

5 lubrication pump

6 cylinder head

7 cylinders

8 reciprocating pistons 9 auxiliary reciprocating pistons

10 longitudinal axis

11 Inner cylinder surface

12 cylinder radius

13 reciprocating piston bottom 14 reciprocating piston bottom surface

15 reciprocating piston outer surface

16 piston radius

17 Auxiliary piston bottom

18 Auxiliary lifting piston bottom surface 19 Auxiliary lifting piston outer circumferential surface

20 auxiliary piston radius

21 Auxiliary piston sliding surface

22 Relief Pistons

23 Relief cylinder 24 Relief line

25 piston spacing

26 ring

27 groove

28 drive shaft

29 drive eccentrics

30 eccentric sliding surface 31 crank pins

32 Drive movement

33 Auxiliary conveyor stroke movement

34 Auxiliary suction stroke movement 35 Delivery volume

36 lubrication volume

37 Conveying stroke

38 Suction stroke movement

39 Auxiliary piston lubrication line 40 Longitudinal slide valve

41 cylinder opening

42 Drive lubrication line

43 rotary slide valve

44 Drive shaft recess

Claims

1. Reciprocating piston pump (1) for pumping a medium with at least one pump module (2) and a drive (3), the at least one pump module (2) having a cylinder head (6), a cylinder (7) and a reciprocating piston (8 ), the reciprocating piston (8) having a reciprocating piston base (13) with a reciprocating piston base surface (14), the cylinder head (6), the cylinder (7) and the reciprocating piston base (13) having a delivery volume (35 ), the reciprocating piston (8) being designed, a drive movement (32) of the drive (3) into a delivery stroke movement (37) and into a suction stroke movement (38) of the reciprocating piston (8) in the cylinder (7) along a longitudinal axis (10) ) to add and wherein the cylinder head (6), the cylinder (7) and the reciprocating piston (8) are formed out, the delivery stroke movement (37) in a delivery of a medium from the delivery volume (35) by reducing the delivery volume (35) implement, characterized in that the reciprocating piston pump (1) has an auxiliary reciprocating piston (9) that the auxiliary reciprocating piston n (9) is arranged between the drive (3) and the reciprocating piston (8) and has an auxiliary piston base (17) with an auxiliary piston base surface (18) that the cylinder (7), the piston (8) and the auxiliary lifting piston base (17) forms a lubricating volume (36) for a lubricant for lubricating contact surfaces between the cylinder (7) on the one hand and the lifting piston (8) and the auxiliary lifting piston (9) on the other hand, so that the cylinder (7), the reciprocating piston (8) and the auxiliary lifting piston (9) are formed out, the drive movement (32) in an auxiliary conveying stroke movement (33) and in an auxiliary suction stroke movement (34) of the auxiliary lifting piston (9) in the cylinder (7) along the longitudinal axis (10) and convert the auxiliary delivery stroke movement (33) of the auxiliary stroke piston (9) into the delivery stroke movement (37) of the reciprocating piston (8) via a lubricant in the lubricating volume, and that the auxiliary reciprocating piston base area (18) is smaller than the reciprocating piston base area (14), so that during the auxiliary conveying stroke movement (33) a pressure of a lubricating medium in the lubricating volume (36) is greater than a pressure of a medium in the conveying volume (35).

2. Reciprocating piston pump (1) according to claim 1, characterized in that the cylinder (7) has a cylinder inner jacket surface (11) which is concentric to the longitudinal axis (10) and has a cylinder radius (12), that the reciprocating piston (8) a reciprocating piston outer circumferential surface (15) concentric to the longitudinal axis (10) with a reciprocating piston radius (16), that the auxiliary reciprocating piston (9) has an auxiliary reciprocating piston outer circumferential surface (19) concentric to the longitudinal axis (10) with an auxiliary reciprocating piston radius (20) ) and that both the reciprocating piston radius (16) and the auxiliary reciprocating piston radius (20) match the cylinder radius (12) and preferably the reciprocating piston radius (16) and the auxiliary reciprocating piston radius (20) are the same are.

3. Reciprocating piston pump (1) according to claim 1 or 2, characterized in that the reciprocating piston (8) has a relief piston (22) and the auxiliary piston (9) in the auxiliary piston base (17) has a relief cylinder (23) matching the relief piston ( 22) that the relief cylinder (23) has a relief volume and / or is connected to a relief volume and that the relief piston (22) is preferably a shaft.

4. Reciprocating piston pump (1) according to claim 3, characterized in that the relief stroke piston (22) and the relief cylinder (23) have a piston distance (25) between the reciprocating piston (8) and the auxiliary reciprocating piston (9) along the longitudinal axis (10) limit to a maximum piston distance.

5. Reciprocating piston pump (1) according to one of claims 1 to 4, characterized in that the reciprocating piston pump (1) has a bearing (4) that the bearing (4) is arranged between the drive (3) and the auxiliary reciprocating piston (9) and is designed to convert the drive movement (32) into the auxiliary conveying stroke movement (33) and the auxiliary suction stroke movement (34).

6. Reciprocating piston pump (1) according to claim 5, characterized in that the drive (3) has a drive shaft (28) that the drive shaft (28) has a drive eccentric (29) with an eccentric sliding surface (30), that the auxiliary lifting piston (9) has an auxiliary lifting piston sliding surface (21), that the eccentric sliding surface (30) and the auxiliary lifting piston sliding surface (21) the bearing (4 ) and that the drive shaft (28) and the auxiliary lifting piston (9) are formed, the drive movement (32) of the drive shaft (28) in

In the form of a rotation via the bearing (4) into the auxiliary conveying stroke movement (33) and the auxiliary suction stroke movement (34).

7. Reciprocating piston pump (1) according to claim 5 or 6, characterized in that the auxiliary lifting piston (9) has an auxiliary lifting piston lubrication line (39), that the auxiliary lifting piston lubrication line (39), the lubricating volume (36) and the auxiliary lifting piston sliding surface ( 21) to supply the bearing (4) with a lubricating medium and that the auxiliary piston lubricating medium line (39) is preferably a channel in the auxiliary piston (9).

8. reciprocating piston pump (1) according to claim 7, characterized in that the auxiliary lifting piston lubrication line (39) has at least one check valve.

9. Reciprocating piston pump (1) according to one of claims 1 to 8, characterized in that the reciprocating piston pump (1) has a longitudinal slide valve (40) for controlling the supply of a lubricating medium into the lubricating volume (36), that the longitudinal slide valve (40) at least a cylinder

Has opening (41) in the cylinder (7) for supplying a lubricating medium into the lubricating volume (36) and that the at least one cylinder opening (41) is preferably a groove, pocket and / or bore.

10. Reciprocating piston pump (1) according to claim 9, characterized in that the at least one cylinder opening (41) has a supply of one

Releases lubricant to the lubricant volume (36) when the Hubkol ben (8) is in the region of a reversal point from the suction stroke movement (38) to the delivery stroke movement (37).

11. Reciprocating piston pump (1) according to one of claims 6 to 10, characterized in that the drive shaft (28) has a drive lubrication line (42) and a rotary slide valve (43) for controlling the supply of a lubricating medium into the bearing (4 ) that the rotary slide valve (43) has a drive shaft recess (44) in the drive shaft (28) over an angle range of rotation of the drive shaft (28), so that only over In the angular range, a lubricant is fed into the bearing (4) and that the drive lubrication line (42) is preferably a channel in the drive shaft (28) and in the drive eccentric (29).

12. Reciprocating piston pump (1) according to claim 11, characterized in that the drive lubrication line (42) has at least one check valve.

13. Reciprocating piston pump (1) according to one of claims 9 to 12, characterized in that the reciprocating piston pump (1) has a lubricating pump (5) for supplying the at least one pump module (2) and / or the drive (3) with a lubricating medium and that the reciprocating piston pump (1) is designed to supply a lubricating medium from the lubricating pump (5) to the longitudinal slide valve (40) and / or to the drive lubrication line (42).