CN103790819A

CN103790819A - Piston pump

Info

Publication number: CN103790819A
Application number: CN201310512744.7A
Authority: CN
Inventors: S·克恩
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2012-10-26
Filing date: 2013-10-25
Publication date: 2014-05-14
Also published as: DE102012219621A1; EP2725226A1

Abstract

The present invention relates to a piston pump (10) form high-pressure transmission of a fluid to be transmitted. The piston pump (10) comprises a pressure generating unit (30) and a control unit (40) which are arranged together in an individual housing (84) and aligned to each other along a common longitudinal axis (18).

Description

Reciprocating pump

Technical field

The present invention relates to a kind of reciprocating pump for high-pressure delivery fluid to be conveyed, it has Pressure generator and control gear.

Background technique

In prior art, disclose a kind of such reciprocating pump, this reciprocating pump is for example applied in high pressure cleaner.This reciprocating pump comprises two assemblies with pressure-generating element and control group component form, on described modular construction, arranges apart from each other.The first assembly consists essentially of has piston rod, the guide bush of pump piston, the stage clip with spring holder and seal element, and the second assembly makes to enter the control unit unification of valve and expulsion valve and other electric mechanical, be particularly useful for connecting and cutting off the drive motor of attaching troops to a unit.Two assemblies interconnect by pressing chamber and for example mutually locate squarely, and wherein, the driving of piston rod and connected pump piston realizes by means of wobble-plate conventionally, and this wobble-plate is connected without relative rotation with the driven shaft of drive motor.

The shortcoming of prior art is, need to be used for the corresponding larger installation room of reciprocating pump in such reciprocating pump due to the layout at the mutual right angle of two assemblies.

Summary of the invention

Therefore, task of the present invention is, a kind of save position, compact and firm reciprocating pump are provided, this reciprocating pump can manufacture inexpensively and this external long-life situation under guarantee high reliability.

This problem solves by the reciprocating pump for high-pressure delivery fluid to be conveyed, this reciprocating pump has Pressure generator and control gear, wherein, described Pressure generator and control gear are arranged in a single housing and in described housing jointly along common longitudinal axis orientation.

Here, the present invention is by realizing the locational requirement of obvious reduction compared with the linear arrangement of Pressure generator and control gear and the layout at the right angle of the common reciprocating pump for high pressure cleaner.In addition,, because simple coaxial structure draws high reliability, what this high reliability was brought thereupon is long working life.Can realize with price and transfer efficiency the total series of different models by one of reciprocating pump unique mode of execution.On the contrary, can apply the parts of unified configuration for different models with disclosed mode of execution in advance, this causes cost savings high in the time producing member, because described member can be with significantly higher number of packages manufacture.In addition, allow to use a large amount of standardized standard piece, for example rolling bearing ball and cylindrical pin according to structure of the present invention.

According to a mode of execution, Pressure generator have can with respect to the pump piston of longitudinal axis moved in coaxial and described control gear have can be respectively with respect to described longitudinal axis moved in coaxial, enter valve and expulsion valve for fluid to be conveyed.

By can with respect to the pump piston of longitudinal axis moved in coaxial and can with respect to longitudinal axis moved in coaxial enter valve and expulsion valve can produce extra high discharge pressure.

Preferably, pump piston is received in cylinder and with piston rod and is fixedly connected with, and this piston rod can be received in the guide bush being connected with cylinder and with respect to this guide bush by means of at least one seal ring sealing axial slip.

Because the piston rod being fixedly connected with pump piston draws especially simply constructing of Pressure generator, wherein, piston rod preferably can oscillatorily move along longitudinal axis by means of suitable eccentric driving device.Piston rod is preferably connected with pump piston force closure ground by joint filling (Verstemmen).

Preferably, cylinder has the cylinder import of at least one moulding with substantially elliptical and at least one piston import for fluid to be conveyed is set in pump piston, wherein, described at least one piston import pass into pump piston perforation in the direction of longitudinal axis in directed center-aisle.

Therefore, fluid to be conveyed enters into the hollow inside of pump piston through casing wall from outside with simple mode and method.The oval physical dimension of cylinder import is guaranteed sufficiently high volume flowrate and is supported in addition the suction certainly of fluid to be conveyed.

According to a mode of execution, pump piston and cylinder form pressing chamber.

Therefore, because defining, piston movement periodically becomes large and volume that diminish.

According to a mode of execution, pump piston has recess on distolateral, for receiving the end face of configuration to the valve gap of control gear.

Therefore, in pump piston, provide the reliable position of valve gap to fix.

Preferably, the end face of valve gap be provided with around flange and in distolateral, blind hole is set, wherein, at least one leaving a blank is radially set in the region of flange, this is left a blank and is connected with described blind hole.

Described in fluid to be conveyed passes, leave a blank and arrive in pressing chamber.Here, blind hole is for entering the valve spring of valve described in saving position and guiding, and wherein, described blind hole has the little degree of depth, to the dead space volume of the air for invading is minimized and guaranteed high as far as possible compression simultaneously.

According to a mode of execution, valve gap is by means of valve spring preload, and this valve spring is supported on cylinder cap or abuts between the pad and the flange of valve gap on cylinder cap in inner side.

By described valve gap spring, make described valve gap force closure and abut on described pump piston.Above flange, (hollow) substantially columniform handle of valve gap has the convex shoulder for the valve spring that leads and feel relieved.

According to a mode of execution, the center-aisle of pump piston is transitioned in valve seat, in this valve seat, receives by means of entering the ball of valve spring pretension as the valve that enters of the fluid for to be conveyed, wherein, enters valve spring and is clamped between ball and the blind hole of valve gap.

Therefore, provide the structure simple in structure that enters valve, this enters valve and has the single part of minimum number.

According to a configuration, pump piston has columniform section, is connecting the section of a taper on this columniform section.

Therefore, draw pump piston with respect to the low friction of cylinder and but sealing efficiently, to can produce high pressure with rational drive efficiency.In particular, the section of taper reduces frictional loss by the effective slip surface reducing between pump piston and cylinder.Fluid to be conveyed is due to the reduction of the friction in the region between its lubrication support pump piston and cylinder.

Preferably, pump piston consists of high performance plastics.

Therefore, little wearing and tearing and the long life-span of reciprocating pump are provided.In addition, the intrinsic elasticity of high performance plastics allows the slightly press fit of pump piston in cylinder for seal action, thereby can save additional piston seal.

According to a mode of execution, cylinder cap has hole, and this hole is transitioned in valve seat, and in this valve seat, reception is using the ball of outlet valve spring pre-tightening as the outlet valve for fluid.

Therefore, outlet valve has the structure of simple structure equally, because it consists of the part of small number equally.

According to a mode of execution, outlet valve spring and ball are received in the hole of end cap, and this end cap is connected with cylinder cap.

Therefore, make the assembling of Pressure generator become simple.Valve outlet port spring can be supported in end cap or be supported in a housing parts of reciprocating pump.

Accompanying drawing explanation

Further illustrate in the following description the present invention according to embodiment illustrated in the accompanying drawings.Accompanying drawing illustrates:

Fig. 1 illustrates according to the sectional view of the reciprocating pump with Pressure generator and control gear of a mode of execution,

Fig. 2-5 illustrate the explanatory view of four running statees of the reciprocating pump in Fig. 1,

Fig. 6 illustrates the enlarged side view of the Pressure generator of the reciprocating pump in Fig. 1,

Fig. 7 illustrates the sectional view of the reciprocating pump in Fig. 6, and

Fig. 8 illustrates the amplification sectional view of the control gear of the reciprocating pump in Fig. 1.

Embodiment

Fig. 1 illustrates the reciprocating pump 10 with Pressure generator 30 and control gear 40 according to a mode of execution.Reciprocating pump 10 comprises preferably illustratively by the thermoplastic of suitable elasticity and/or pump piston 12 that heat cured plastic materials is made, this pump piston can oscillatorily move along longitudinal axis 18 by means of piston rod 16 in cylinder 14, is move upward and move downward in Fig. 1 illustratively.Piston rod 16 can be received in the guide bush 20 of hollow cylinder substantially and with respect to this guide bush by seal ring 22,24 sealings axial slip.Piston rod 16 drives by means of the eccentric driving device 26 schematically showing, and therefore, makes pump piston 12 hopefully oscillatorily move upward in cylinder 14 along longitudinal axis 18 and move downward.But be to be noted that suitable eccentric driving device is enough open and be not theme of the present invention to those skilled in the art, thereby the detailed description of saving eccentric driving device 26 here for the terseness illustrating.

Pump piston 12 and cylinder 14 are defined for the pressing chamber 28 of the fluid of carrying by means of reciprocating pump 10 and form thus the Pressure generator 10 of reciprocating pump 10, and this fluid here exemplarily shows with arrow 46.Enter valve and the common control gear 40 that forms reciprocating pump 10 of

expulsion valve

32,34.

In cylinder 12, preferably arrange three and have the cylinder import of distinguishing illustratively oval moulding, wherein, two the cylinder imports that can see here have reference character 42,44.Fluid to be conveyed enters into reciprocating pump 10 by cylinder import.Preferably the oval-shaped physical dimension of three cylinder imports is guaranteed sufficiently high volume flowrate and is supported the suction certainly of fluid to be conveyed 46 at this.Described cylinder import is connected with preferably three piston imported hydraulic of pump piston 12, wherein, can see an only piston import 48 here.Piston import 48 is led to respectively one through in the center-aisle 50 of pump piston 12.

Center-aisle 50 is exemplarily transitioned in valve seat 52, in this valve seat, receives by means of the ball 56 that enters valve spring 54 pretensions, and the common formation of described valve seat and ball enters valve 32.Enter valve spring 54 to refer to from the end portion supports of ball 56 at valve gap here,

in 60 blind hole 58, this valve gap is arranged between pump piston 12 and pad 62, and this pad (in Fig. 1) is positioned at cylinder cap 64 belows.Pad 62 has the hole 68 for allowing fluid to be conveyed pass.

Valve gap 60 is by means of valve gap spring 66 pretensions, therefore, valve gap 60 each running state of reciprocating pump 10 exert oneself in locking manner (in Fig. 1) abut on pump piston 12 upsides.Correspondingly, the piston rod 16 being fixedly connected with pump piston 12 is because the effect of valve gap spring 66 clings on eccentric driving device 26.Alternatively, valve gap spring 66 directly (in Fig. 1) is supported on cylinder cap 64 downsides, thereby can save pad 62.

In addition, hole 70 is set in cylinder cap 64, this hole 70 is transitioned in valve seat 72, in this valve seat, receives by means of the ball 76 of expulsion valve spring 74 mechanical pretensions for forming expulsion valve 34.Cylinder cap 64(is in Fig. 1) be connected with end cap 78 at upside, wherein, through hole 80 is set in end cap 78, the finger that receives expulsion valve 74 in this through hole is fixed to carry out position from the end of ball 76.Fluid 46 to be conveyed leaves reciprocating pump 10 by expulsion valve 32 along the direction of arrow 82.Enter valve spring 54, valve gap spring 66 and expulsion valve spring 74 preferable configuration and be columniform stage clip and by metal, enough flexible material is made.Valve seat 72 in the output area in hole 70 has chamfered edge and the radius with ball adaptation, to guarantee reliable seal action.

Compared with conventional piston pump for high pressure cleaner, due to Pressure generator 30 and there is the control gear 40 that enters valve and

expulsion valve

32,34 and valve gap 60 and draw along the linearity-coaxial layout of longitudinal axis 18 structure of saving very much position of reciprocating pump 10, this reciprocating pump makes to be integrated in housing or pump case 84 and becomes simple, wherein, according to an embodiment, housing 84 can be made up of cylinder 14.Because the quantity of for this reason essential member is little, reciprocating pump 10 can be manufactured inexpensively in addition and realize the long life-span in the situation that of high reliability and maintenance cost.In addition, due to the modular structure of reciprocating pump 10, multiple reciprocating pumps are combined into a pump unit in a single housing or multiple housing with building block principle, so that realization for example has the different high pressure cleaners that require aspect the quantity delivered of fluid to be conveyed and/or discharge pressure, obtain thus further cost savings potentiality.Here, for example two reciprocating pumps 10 constructed according to the invention can be located opposed to each other about eccentric driving device in the end opposite of diameter.In addition can drive by means of an eccentric driving device more than the reciprocating pump of two.

In service at reciprocating pump 10, if piston rod 16 moves downward with pump piston 12 direction (in Fig. 1) along arrow 86 together with described piston rod in cylinder 14, piston import 48 and other the piston imports that can't see that fluid 46 to be conveyed is connected by

cylinder import

42,44 and with described cylinder imported hydraulic are drawn in intermediate conduit 50 and are drawn into therefrom in closed chamber 28, (are overcoming by after entering the spring force that spring 54 applies) and are opening on this flow direction of fluid because enter valve 32.On the contrary, if the moving direction of pump piston 12 reverses, entering valve 32, to close and be inhaled into fluid in pressing chamber 28 compressed so for a long time by means of pump piston 12, until starting to overcome spring force and the expulsion valve 34 of expulsion valve spring 74, the power effect of the hydrodynamic pressure in pressing chamber 28 opens, thereby make the fluid under high pressure from now on to leave pressing chamber 28 along the direction of arrow 82 by described

hole

68,70,80, this arrow has for example illustrated a direction of taking the spray gun of position, for example high pressure cleaner.Due to the moving upward and moving downward of cycle of pump piston 12, the course of conveying of summarizing above of reciprocating pump 10 repeats, thereby makes fluid pulsation and under high pressure leave expulsion valve 34 along the direction of arrow 82.

Fig. 2 to 5(is same with reference to described accompanying drawing in the further illustrating of specification) explanatory view of four running statees of the reciprocating pump 10 in Fig. 1 is shown.

Fig. 2 is illustrated in the pump piston 12 in the dead center position of (in Fig. 2) bottom, the namely pump piston in the darkest position of the pump piston in the pressing chamber 28 of reciprocating pump 10 illustratively.In the dead center position of this bottom, reciprocating pump 10 enter valve 32 and expulsion valve 34 cuts out because enter valve spring 54 and expulsion valve spring 74 can apply sufficiently high spring force to ball 56 and 76.

Enter valve spring 54 here, and there is special significance.Except entering the guide function of ball 56 of valve 32, its main task is, once the corresponding sucting stage of fluid 46 to be conveyed finishes, quick closedown enters valve 32.The spring indicatrix that enters valve spring 54 here, has been determined the pressure of opening that enters valve 32.This is opened pressure and should be in the scope between 0.1-0.25bar, therefore guarantees that the air that may also exist can be inhaled into jointly.By entering careful harmonious 85% to 90% the volumetric efficiency that reaches of spring force of valve spring 54.Save and enter the obvious decline that valve spring 54 can cause this efficiency because, in the time that compression stage starts, ball 56 can not be enough pressed onto rapidly on the valve seat of pump piston 12 and thus a part for fluid to be conveyed from pressing chamber 28, spill.

Fig. 3 illustrates corresponding sucting stage, in this sucting stage, treat that the fluid 46 carried by means of reciprocating pump 10 is inhaled in pressing chamber 28 by cylinder import 44 and piston import 48 and the every other cylinder import that can not see and piston import by means of pump piston 12 here.

Fig. 4 illustrates pump piston 12, and this pump piston continues motion (in figure and 4 upwards) from its position shown in Figure 3 towards the direction of the dead center position on the top shown in Fig. 5.Here, the pressure in pressing chamber 28 rises consumingly because reciprocating pump 10 enter valve 32 and expulsion valve 34 cuts out.Only have when the such degree rising of the hydrodynamic pressure to be conveyed in pressing chamber 28, the power effect that makes to cause thus expulsion valve spring 74 is compressed and expulsion valve 34 in ball 76 lift and fluid to be conveyed and in high pressure is discharged by expulsion valve 34 and guide into while taking position by suitable pipeline from its valve seat, expulsion valve 34 is just opened.

Fig. 5 illustrates the dead center position on pump piston 12 (in Fig. 5) top.Meet or exceed behind the dead center position on top closed expulsion valve 34 again, wherein, retaining the residual capacity of the fluid to be conveyed 46 in pressing chamber 28.For this residual capacity is kept to the least possible, the degree of depth of the blind hole 58 in valve gap 60 is so little, makes to enter valve spring 54 and occupy the largest portion of the volume of blind hole 58.Therefore the compressed capability that, the so-called dead space volume in pressing chamber 28 is reduced to minimum and reciprocating pump 10 rises overally.During pump piston 12 moves upward, the pressure declining in pressing chamber 28 is responsible for making to enter valve 32 and is opened, thereby fluid to be conveyed can flow into again in pressing chamber 28 and therefore make whole course of conveying periodically repeat as described above.

Fig. 6 illustrates the pump piston 12 of the Pressure generator 30 of the reciprocating pump in Fig. 1.This pump piston 12 about longitudinal axis 18 exemplary symmetric constructions has columniform section 90 illustratively, is connecting the section 92 of a taper on this cylindrical sector.The section 92 of described taper is for mechanical connection piston rod (Fig. 1 16) and reduce in addition the friction between pump piston 12 and cylinder (14 in Fig. 1), because the surface of contact between described cylinder (14 in Fig. 1) and the section 92 of described taper can be ignored little.The sealing section 94 of described section 90 is mainly used in pump piston 12 to seal with respect to cylinder (14 in Fig. 1).

Pump piston 12 is preferably by being formed by fiber reinforced high performance plastics if desired, and this high performance plastics has high wear resistance, high shape stability and the immunity significantly with respect to aggressive chemistry medium.Due to the intrinsic elasticity of plastic materials, pump piston 12 is preferably inserted in the cylinder (14 in Fig. 1) of reciprocating pump (10 in Fig. 1) under the sealed condition of pressure gently, thus unessential any other seal element, for example piston ring or like that.

Preferably, at least one and three for example oval-shaped piston imports at least substantially are illustratively set in pump piston 12, in these piston imports, only can see piston import 48 here.These piston imports be preferably evenly spaced apart and around the circle distribution of pump piston 12 be arranged in this pump piston.The main axis of oval-shaped piston import extends in the direction of longitudinal axis 18, described piston import is for the supply of the mobile optimum of fluid to be conveyed (Fig. 1 46), wherein, by oval shape realize high volume flowrate and simultaneously supporting piston pump (10 in Fig. 1) from inlet capacity.Described preferably three piston imports and center-aisle 50 hydraulic connectings, this center-aisle is configured in pump piston 12 symmetrically about longitudinal axis 18.

Fig. 7 illustrates the pump piston 12 in Fig. 6 with columniform section 90, and this section is transitioned in the section 92 of the taper for connecting piston rod (Fig. 1 16).Realize the essential tight seal between pump piston 12 and cylinder (in Fig. 1 14) by means of the sectional sealing section 94 of the portion as columniform section 90.

Pump piston 12 distolateral 96 in the recess 98 of tank shape is set, this recess is for receiving the unshowned valve gap here (60 in Fig. 1) that enters valve (Fig. 1 32).Piston import 48 and other piston import 100 and other (can not see) piston import are tilted to be directed upwards towards with the exemplary roughly angle [alpha] of 70 ° respectively and are extended towards the direction of described recess 98.Here, three piston imports are exemplary turns up the soil and distributes and arrange on the circumference of pump piston 12 with 120 ° of spaces respectively.

Pump piston 12 with the same recess 104 that approximate tank shape is set in distolateral 96 opposed downsides 102, this recess connects piston rod (Fig. 1 16) for force closure ground, for example by joint filling, be pressed into, welding, bonding, be spirally connected, riveted joint or like that.Lead in valve seat 106 with the intermediate conduit 50 of longitudinal axis 18 concentric structures, in this valve seat, receive ball 56.Valve seat 106 comprises radius 108, connects for example 45 °-chamfered edge 110 on this radius.Here, the radius of radius 108 and ball 56 suitable and with the coefficient situation of chamfered edge 110 under guarantee the reliable sealing of described ball 56 in valve seat 106.Valve seat 106 enters the part of valve (32 in Fig. 1) as the control gear (40 in Fig. 1) of reciprocating pump (10 in Fig. 1) with spring-loaded ball 56 and the common formation of described valve gap (60 in Fig. 1).

For the seal action of pump piston 12 in the cylinder (14 in Fig. 1) of further supporting piston pump (10 in Fig. 1), the preferably same taper of the sealing section 94 ground structure of columniform section 90, the wall thickness 112 that namely seals section 94 starts from the bottom 114 of recess 98 to reduce towards described distolateral 96.

Fig. 8 illustrates the valve gap 60 in Fig. 1, and this valve gap exemplarily has columniform moulding substantially, has the flange 124 of the Flange-shaped Parts of the radially outer sensing forming in the handle 120 of substantial cylindrical and in the region of end face 122.Due to the power effect of valve gap 66, this flange 124 abuts in regularly on pump piston (12 in Fig. 1) in each running state of reciprocating pump (10 in Fig. 1).In addition, in the region of end face 122, a blind hole 58 and longitudinal axis 18 are set in valve gap 60 with one heart.

Blind hole 58 have for enter valve spring (Fig. 1 54) after the convex shoulder 126 that reclines.In addition, two and four leave a blank (these in leaving a blank, can only see that two, rear portion leave a blank 128,130) are illustratively set preferably in valve gap 60 here.These are left a blank and preferably on the circumference of valve gap 60, arrange and give equably the lid configuration of how much with 90 °-calibration.Blind hole 58 is by the interruption of leaving a blank, thereby fluid to be conveyed (46 in Fig. 1) is not hindered and can arrive in pressing chamber (28 in Fig. 1) with little flow resistance.

According to the present invention, the degree of depth 132 of blind hole 58 is as far as possible little.Therefore make the dead space volume of the air entering as far as possible little, wherein, realize equally the high compression of reciprocating pump (10 in Fig. 1).Above flange 124, construct a little convex shoulder 134, this convex shoulder is used for making valve gap spring 66 to feel relieved along longitudinal axis 18.

Claims

1. the reciprocating pump for high-pressure delivery fluid to be conveyed (10), it has Pressure generator (30) and control gear (40), it is characterized in that, described Pressure generator (30) and described control gear (40) are arranged in a single housing (84) and in described housing jointly along common longitudinal axis (18) orientation.

2. reciprocating pump according to claim 1, it is characterized in that, described Pressure generator (30) have can with respect to the pump piston (12) of described longitudinal axis (18) moved in coaxial and described control gear (40) have can be respectively with respect to longitudinal axis (18) moved in coaxial, enter valve (32) and expulsion valve (34) for described fluid to be conveyed.

3. reciprocating pump according to claim 1 and 2, it is characterized in that, described pump piston (12) is received in described cylinder (14) and with piston rod (16) and is permanently connected, described piston rod can be received in the guide bush (20) being connected with described cylinder (14) and by means of at least one seal ring (22,24) axial slip and seal with respect to described guide bush.

4. reciprocating pump according to claim 3, it is characterized in that, described cylinder (14) has the cylinder import (42 of at least one moulding with substantially elliptical, 44) and at least one piston import (48 for described fluid to be conveyed is set in described pump piston (12), 100), wherein, described at least one piston import (48,100) passes in the center-aisle (50) of perforation ground orientation in the direction of described longitudinal axis (18) of described pump piston (12).

5. according to the reciprocating pump described in claim 3 or 4, it is characterized in that, described pump piston (12) and described cylinder (14) form pressing chamber (28).

6. according to the reciprocating pump described in any one in the claims, it is characterized in that, described pump piston (12) has recess (98) on distolateral (96), and described recess is for receiving the end face (122) of the valve gap (60) that is attached to described control gear (40).

7. reciprocating pump according to claim 6, it is characterized in that, the end face (122) of described valve gap (60) be provided with around flange (24) and blind hole (58) is set in described end face (122), wherein, in the region of described flange (24), arrange at least one radially leave a blank (128,130),, leave a blank and be connected with described blind hole (58).

8. according to the reciprocating pump described in claim 6 or 7, it is characterized in that, described valve gap (60) is by means of valve gap spring (66) pretension, and described valve gap spring supporting abuts between the pad (62) and the flange (124) of described valve gap (60) on described cylinder cap at cylinder cap (64) or in inner side.

9. according to the reciprocating pump described in any one in claim 4 to 8, it is characterized in that, the center-aisle (50) of described pump piston (12) is transitioned in valve seat (52), in described valve seat, receive by means of the ball (56) that enters valve spring (54) pretension as entering valve (32) for described fluid to be conveyed, wherein, described in, entering valve spring (54) is clamped between described ball (56) and the blind hole (58) of described valve gap (60).

10. according to the reciprocating pump described in any one in claim 2 to 9, it is characterized in that, described pump piston (10) has columniform section (90), and the section (92) of a taper is connected on described columniform section.

11. according to the reciprocating pump described in any one in claim 2 to 10, it is characterized in that, described pump piston (12) consists of high performance plastics.

Reciprocating pump in 12. according to Claim 8 to 11 described in any one, it is characterized in that, described cylinder cap (64) has hole (70), described hole is transitioned in valve seat (72), and in described valve seat, reception is using the ball (76) of outlet valve spring (74) pretension as the outlet valve (34) for described fluid to be conveyed.

13. reciprocating pumps according to claim 12, is characterized in that, described outlet valve spring (74) and described ball (76) are received in the hole (80) of an end cap (78), and described end cap is connected with described cylinder cap (64).