PISTON PUMP

Abstract

A piston pump configured to pump a fluid and including an inlet channel, an outlet channel, a piston, an armature, an elastic element, a first check valve, a piston chamber, a longitudinal axis, a winding support, and a coil. The piston is movably supported parallel to the longitudinal axis in a piston chamber and has a first face with a piston channel inlet, a second face with a piston channel outlet, and a piston channel connecting the piston channel inlet and the piston channel outlet. The piston is biased in a first axial direction by the elastic element. The first check valve is arranged in the piston channel. The coil has at least one winding arranged on the winding support. The inlet channel is configured to communicate with the piston channel inlet and the outlet channel is configured to communicate with piston channel outlet.

Claims

1.-15. (canceled)

16. A piston pump for pumping a fluid, the piston pump comprising: an inlet channel, an outlet channel, a piston, an armature, an elastic element, a first check valve, a piston chamber, a longitudinal axis, a winding support, and a coil, wherein: the piston is movably supported parallel to the longitudinal axis in a piston chamber, the piston comprises a first face with a piston channel inlet, a second face with a piston channel outlet, and a piston channel connecting the piston channel inlet and the piston channel outlet, the piston is biased in a first axial direction by the elastic element, the first check valve is arranged in the piston channel, the coil has at least one winding, wherein the at least one winding is arranged on the winding support, the inlet channel is configured to communicate with the piston channel inlet and the outlet channel is configured to communicate with piston channel outlet, a sleeve section of the winding support delimits at least a section of the piston chamber in the radial direction.

17. A piston pump according to claim 16, wherein the winding support provides a linear bearing for the piston.

18. A piston pump according to claim 16, wherein the piston has a peripheral surface, wherein the winding support abuts against the peripheral surface of the piston.

19. A piston pump according to claim 16, wherein the piston is at least partially located in a recess of the winding support.

20. A piston pump according to claim 16, wherein the elastic element is located in between of the piston and the armature.

21. A piston pump according to claim 16, wherein the at least one first check valve comprises a first check valve insert, wherein the first check valve insert is located in the piston channel and engages in at least one radially extending recess of the piston channel.

22. A piston pump according to claim 16, wherein the first check valve insert comprises a first valve body and a first valve body support.

23. A piston pump according to claim 16, wherein: a stem with a stem axis is attached to the first valve body, the stem being movably supported by the first valve body support thereby allowing a translation of the stem parallel to the stem axis, the first valve body comprises at least two attachment legs, wherein a first section of each attachment leg extends radially outwards withing 30, a second section of the attachment legs is attached to the first section and extends parallel to the longitudinal axis with 30 and a third section of the attachment leg is attached to the second section and extends at in the radial direction within 30, at least the free end of the third section engages into the at least one radial recess of the piston channel.

24. A piston pump according to claim 16, wherein a guide body extends from the attachment legs towards the attachment leg facing side of the first valve body.

25. A piston pump according to claim 24, wherein at least a portion of the stem facing surface of the guide body is a linear bearing surface movably supporting the stem.

26. A piston pump according to claim 25, wherein at least a portion of the stem facing surface of the guide body is a linear bearing surface movably supporting the stem.

27. A piston pump according to claim 16, wherein the first valve body is movable between an extended position, in which the first valve body closes a valve seat in a retracted position, wherein in the retracted position a gap is provide between the first valve seat and the first valve body.

28. A piston pump according to claim 27, wherein a protrusion of the stem and/or the first valve body abut an axially facing surface of the guide body in the retracted position.

29. A piston pump according to claim 16, wherein the winding support is detachably attached to a protective tube.

30. A piston pump according to claim 16, wherein the piston pump has a first fitting and a second fitting.

31. A piston pump according claim 30, wherein the at least one second check valve is located in the second fitting and/or the first fitting.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In the following, the invention will be described by way of example, without limitation of the general inventive concept, on examples of embodiment and with reference to the drawings.

[0075] FIG. 1 presents a sectional view of a first example of a piston pump.

[0076] FIG. 2 presents a side view of the first example of a piston pump.

[0077] FIG. 3 presents a rear view of the first example of a piston pump.

[0078] FIG. 4 presents a sectional view of a second example of a piston pump.

[0079] FIG. 5 presents a side view of a valve insert.

[0080] FIG. 6 presents a perspective view of the valve insert.

[0081] FIG. 7 presents a rear view of a valve body support.

[0082] Generally, the drawings are not to scale. Like elements and components are referred to by like labels and numerals. For the simplicity of illustrations, not all elements and components depicted and labeled in one drawing are necessarily labels in another drawing even if these elements and components appear in such other drawing.

[0083] While various modifications and alternative forms, of implementation of the idea of the invention are within the scope of the invention, specific embodiments thereof are shown by way of example in the drawings and are described below in detail. It should be understood, however, that the drawings and related detailed description are not intended to limit the implementation of the idea of the invention to the particular form disclosed in this application, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

[0084] The piston pump 1 in FIGS. 1 to 3 has a longitudinal axis L, an inlet opening 320 and an outlet opening 430. The vector F may be parallel to the flow direction along the longitudinal axis L and indicates the forward direction and hence points in the forward direction, i.e., from the rear to the front.

[0085] The piston pump 1 may include a winding support 600. The winding support 600 may include or essentially be a sleeve and with a peripheral surface 620 and an inner surface 610. A coil may be wound onto the winding support's 600 peripheral surface 620. The winding support may hence as well be referred to as winding form or coil form or coil body. To declutter the FIG. 1 only the connection lines 900 of the coil are depicted.

[0086] As shown, the inner surface 610 of the winding support 600 may delimit a piston chamber 180 radially. In the rearward (axial) direction, the piston chamber 180 may be delimited by end by a front end surface 170 of an armature 100 with an armature channel 110 connecting a first armature face 160 and a second armature face 170. The armature 100 may be attached to the inner surface 610 of the winding support 600 and in between of a first fitting 300 with inlet opening 320 and the piston chamber 180. In the forward direction F, the piston chamber may be delimited by a rearward facing surface 460 (rear surface) of the second fitting 400.

[0087] The first fitting 300 may include a fitting channel 310 that may be considered as at least a first portion of an inlet channel.

[0088] A piston 200 may be movably supported by the inner surface 610 of the winding support 600 inside the sleeve section of the winding support 600. The inner surface 610 of the winding support 600 may hence be considered as a plain bearing surface. Similarly the peripheral surface 240 of the piston (piston peripheral surface 240) may be considered as a as a plain bearing surface being coaxially aligned with the inner surface 610.

[0089] In between if the second fitting's rear surface 460 and the forward facing surface 270 of the piston 200 (i.e., of the second piston face 270) may be an optional damping washer 880 inside the piston chamber 180.

[0090] An elastic element 280 may be located inside the piston chamber 180 and may be configured to bias the piston 200 in an axial direction. Like in the presented example, the piston may be preloaded by the elastic element 280 in the forward direction, however it could as well be preloaded in the opposite direction. In the present example, the elastic element 280 may be located in between of the rearward facing surface 260 (first surface 260) of the piston 200 and an abutment 190. The abutment 190 may be provided by a recess 114 in the second surface 170 of the armature 100.

[0091] The piston may have a piston channel 210 with a first piston channel section 212 and second piston channel section 214. The piston channel 210 connects a piston channel inlet 220 in the first piston face 260 with a piston channel outlet 230 in the second piston face 270.

[0092] The piston channel 210 may be radially delimited by a piston channel wall 250. The diameter of the second piston channel section 214 may be greater than the diameter of the first piston channel section 212. The inner surfaces of the two piston channel sections 212, 214 may be connected by an intermediate surface that may provide an abutment for a first valve body 710 (cf. FIG. 5) and can hence be considered as valve seat.

[0093] The second piston channel section houses a first valve insert 700, being depicted in FIGS. 5 and 6 and which will be explained below in more detail. The first valve insert 700 may engages into an annular radial recess 258.

[0094] The second fitting 400 may feature a fitting channel that may as well be the outlet channel 410 with an outlet opening 430. In the outlet channel 410 may be a (second) valve chamber (considering the second piston channel as a first valve chamber) accommodating a second valve insert 750. The second valve insert may be identical to the first check valve insert 700 and engages into a radially extending recess 458 of the outlet channel 410.

[0095] To operate the piston valve 100 the coil may be connected to a power supply and generates a magnetic field. Due to the magnetic field, the piston moves towards armature 100 and the fluid flows though from through the piston channel towards the rearward face of the second fitting. If the current through the coil is interrupted, the elastic element may push the piston 100 back in the depicted position and thereby the fluid through the outlet 430.

[0096] As can be seen in FIGS. 2 and 3, the piston pump may have a housing 550 including a protective tube 500 (see as well FIG. 1).

[0097] The piston pump 100 in FIG. 4 is almost identical to the piston pump as shown in FIG. 1 to FIG. 3 and the description of FIG. 1 to FIG. 3 may be read on FIG. 4 as well. The only difference is that the piston pump 100 in FIG. 4 has a plain bearing sleeve 800 located in a forward section the piston chamber 180 and provides a plain bearing surface movably supporting the piston 100 in the piston chamber 180. At this point it is noted that the plain bearing sleeve preferably does not extend through the entire piston chamber 180, i.e., preferably as shown the inner surface 610 of the winding support may be in contact with the fluid inside the piston chamber.

[0098] A check valve insert 700/750 like the first check valve insert 700 and/or the second check valve insert 750 preferably includes a valve body 720 and a stem 724 extending from the front side of the valve body 720 through hole 719 in a valve body support 710 (see FIG. 5 to FIG. 7). The valve body support 710 may have at least two attachment legs 712. In the example, four attachment legs 712 are shown but other numbers can be present as well. Each attachment leg 712 may have three sections 714, 716, 718: A first section 714 may extend radially outwards. A second section 716 may extend from the distal end of the first sections 714 of the attachment legs 712 at least essentially parallel to the axial direction L (cf. FIGS. 1 and 4). The third sections 718 of the attachment legs 712 may extend from the end of the second section 716 at least essentially radially outwards and may engage in a radially extending recess such as the recess 258, 458 in FIG. 1 or FIG. 4

[0099] The valve body support 710 may further include a guide body that may extend from the attachment legs 712 towards the valve body 720. The guide body 715 may radially support and hence coaxially align an elastic member 730. Further the stem facing surface of the guide body 715 may radially support the stem 724 and if retracted (see FIG. 5) axially support the valve body 720. The guide body 715 thereby contributes to avoid valve body flatter.

[0100] The valve body 720, which is sometimes as well referred to as plunger 720 or valve member 720 may have an annular groove 726 supporting a gasket 740. For example, the gasket may be a simple O-ring, but other types of gaskets may as well be used as explained above.

[0101] It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide a piston pump. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

LIST OF REFERENCE NUMERALS

[0102] 1 piston pump [0103] 100 fixed armature [0104] 110 armature channel [0105] 114 recess in armature [0106] 160 first (rear end) armature face [0107] 170 second (front end) armature face [0108] 180 piston chamber [0109] 190 abutment [0110] 200 piston [0111] 210 piston channel [0112] 212 first piston channel section [0113] 214 second piston channel section [0114] 220 piston channel inlet [0115] 230 piston channel outlet [0116] 240 piston peripheral surface [0117] 250 piston channel wall [0118] 258 groove/grooves/radially extending recess [0119] 260 first piston face [0120] 270 second piston face [0121] 280 elastic element [0122] 300 first fitting [0123] 310 first fitting channel/inlet channel [0124] 320 inlet opening [0125] 380 sealing/gasket [0126] 400 second fitting [0127] 410 second fitting channel/outlet channel [0128] 430 outlet opening [0129] 458 groove/grooves/radially extending recess [0130] 460 rear surface of second fitting [0131] 500 protective tube [0132] 550 housing [0133] 600 winding support/coil body [0134] 610 inner surface [0135] 620 peripheral surface [0136] 700 first check valve [0137] 710 valve body [0138] 712 attachment legs [0139] 714 first section of attachment legs [0140] 715 guide body [0141] 716 second section of attachment legs [0142] 718 third section of attachment legs [0143] 719 through hole [0144] 720 valve body/plunger [0145] 724 stem [0146] 726 annular groove [0147] 730 elastic member [0148] 740 gasket [0149] 750 second check valve [0150] 800 sleeve/plain bearing sleeve [0151] 880 damping washer [0152] 900 connection lines [0153] L longitudinal axis [0154] F flow direction