WO2018153923A1

WO2018153923A1 - Guide element, piston device, and method for producing a guide element

Info

Publication number: WO2018153923A1
Application number: PCT/EP2018/054288
Authority: WO
Inventors: Marko VOIGT; Patrick Klein
Original assignee: Elringklinger Ag; ElringKlinger Kunststofftechnik GmbH
Priority date: 2017-02-21
Filing date: 2018-02-21
Publication date: 2018-08-30
Also published as: DE102017202785A1

Abstract

The invention relates to a guide element, which is simply constructed and permits efficient guidance of a piston in the piston receptacle, for example a cylinder. According to the invention, the guide element comprises the following: an at least approximately ring-shaped or ring-section-shaped base, which extends at least approximately annularly or in the shape of an annular section in a circumferential direction with respect to a ring mid-axis, and at least one connecting section for the elastic and/or flexible connection of edge sections of edges of the base, which are located opposite one another in an axial direction extending parallel to the ring mid-axis.

Description

Guide element, piston device and method for producing a guide element

The present invention relates to a guide element for a piston of a piston device, a piston device and a method for producing a guide element. Guiding elements are used in particular in piston devices, for example reciprocating compressors. In particular, guide elements are used in dry-running piston compressors, which manage without a lubricant in the cylinder.

The present invention has for its object to provide a guide element which is simple in construction and allows efficient guidance of a piston in the piston receiving, for example, a cylinder.

This object is achieved according to the invention by a guide element for a piston of a piston device, wherein the guide element comprises:

an at least approximately annular or ring-shaped base body which extends at least approximately annularly or annularly in a circumferential direction with respect to a ring center axis;

at least one connecting portion for the elastic and / or flexible connection of edge portions of edges of the base body, which face each other in an axial direction extending parallel to the annular central axis.

By virtue of the fact that the guide element preferably comprises at least one connecting section for the elastic and / or yielding connection of edge sections of edges of the base body, in particular especially in the clamped state of the guide element thermal

Material expansions are compensated in the axial direction and / or compensated.

By means of the at least one connecting portion are preferably two edge portions of the base body, which are opposite to each other in a direction parallel to the annular central axis axial direction, in particular connected to each other such that the guide element is in the clamped state under a particular elastic mechanical stress.

Singular-listed elements may preferably also be present multiple times, wherein in particular one, several or all of the elements have the features outlined.

It may be favorable if the guide element is in an assembled, ready-to-use state and / or without thermal expansions in an at least approximately mechanically tension-free state.

Alternatively, it can be provided that the guide element in the assembled, ready-to-use state is under, preferably axial, elastic prestress.

The guide element extends in the clamped state, in particular axially, at least approximately free of play in a recess of the piston.

Preferably, an increased frictional force between the piston and the piston receptacle, which is caused by thermal expansion of the guide element in a radial direction of the annular central axis, can be avoided.

In particular, pinching and / or jamming of the piston in the piston receptacle and / or faster wear of the guide element due to increased frictional force can be avoided. In the clamped state of the guide element, in particular, a pressure acts on the main body of the guide element.

It may be advantageous if, in the clamped state of the guide element, a mechanical pressure in the axial direction of the main body acts on the guide element and / or is applied.

Preferably, the guide element is in the clamped state under a mechanical stress, in particular under a mechanical compressive stress.

Preferably, by means of biasing a centering and / or fixing of the guide element is realized in a recess of the piston in the axial direction.

In particular, due to optimized assembly, centering and / or fixing of the guide element in a recess of the piston in the circumferential direction is realized.

It may be favorable if the guide element is designed as a piston ring or piston ring section.

Additionally or alternatively it can be provided that the guide element is a different element of a sealing piston ring, which is arranged in particular in a region of the piston skirt, which lies on a side opposite the piston head side of a piston ring groove.

In particular, the guide element is designed as a curved or bent guide band and / or as a curved or curved flat material. "Flat material" is a material which, in particular in one dimension, has a greater extension than in the other dimensions.

Preferably, the ring center axis is an axis of symmetry with respect to the circumferential direction of the main body.

The guide element preferably comprises a plastic material or is formed from a plastic material.

The guide element comprises in particular a polymeric plastic material or is formed from a polymeric plastic material.

Preferably, the guide element has one or more projections, which protrude away from a central region of the base body to the outside. The one or more projections in particular form part of the edge portions of the edges of the base body.

An axially outer surface of the one or more projections forms in particular one or more contact surfaces.

The one or more protrusions preferably form one or more axial protrusions that extend in an axial direction parallel to the annular central axis.

It may be favorable if the one or more projections form local axial projections which extend locally in the axial direction at a maximum distance from the central region of the main body of the guide element.

The one or more contact surfaces are in the clamped state of the guide element preferably completely or partially in direct contact with flanks of recesses of the piston. In particular, the one or more contact surfaces are in the clamped state of the guide element completely or partially in material contact with flanks of recesses of the piston.

Preferably, the guide element is held under elastic bias between the two flanks. In particular, in the clamped state of the guide element, a normal stress acts perpendicular to a main extension plane of the contact surfaces and / or the flanks.

This can in particular offer the advantage that creep of the guide element in the clamped state can be at least approximately avoided.

Protrusions arranged in the axial direction on opposite edges of the guide element, in particular their contact surfaces, are preferably offset relative to one another with respect to the direction of rotation of the main body.

Two mutually axially opposite edges of the main body of the guide element are preferably each formed by a plurality of edge portions. The plurality of edge portions are in particular formed alternately as axial projections and axial recesses.

It can be provided that in the axial direction at least one axial projection, in particular directly, is arranged opposite at least one axial recess.

Preferably, all the axial projections in the axial direction, in particular directly, are arranged opposite to an axial recess.

The guide element preferably has a substantially zig-zag pattern with respect to its edges which are opposite one another in the axial direction. Alternatively it can be provided that one or both of the two edges of the main body is formed continuously coaxial with the direction of rotation.

In particular, an axial projection directly adjoins an axial recess at an edge or at both edges of the two axially opposite edges of the base body in the circumferential direction.

It may be favorable if the at least one connecting section comprises an indentation, by means of which an escape region is created, into which the guide element expands in the clamped state with an increase in temperature, while the axial distance between two axially opposed contact surfaces remains at least approximately constant.

The axial distance is measured in particular parallel to the axial direction with respect to the annular central axis.

Preferably, a free space formed by an escape area in the clamped state of the guide element absorbs thermal expansions of the guide element, in particular in such a way that the axial distance between two contact surfaces lying opposite one another in the axial direction remains essentially unchanged.

Preferably indentations of the connecting portions are arranged on a relative to the ring center axis radially outer side of the main body of the guide element.

Additionally or alternatively, indentations of the connecting sections are arranged in the axial direction above and / or below on the respective edges of the base body. In particular, the indentations form axial recesses in the main body of the guide element. Preferably, the base body of the guide element in areas of the indentation in the axial direction and / or in the radial direction a reduced material thickness compared to areas of the body without indentation.

The material thickness of the base body in areas of the indentation is preferably about 80% or less of the material thickness of the base body in areas without indentation.

In particular, the material thickness of the main body in areas of the indentation is preferably about 60% or less of the material thickness of the main body in areas without indentation.

For example, the material thickness of the body in areas of the indentation is about 40% or less of the material thickness of the body in areas without indentation.

It may be favorable if the main body of the guide element has a reduced material thickness in regions of the indentation perpendicular to the ring central axis.

Alternatively or additionally, it may be provided that the base body of the guide element in areas of the recess parallel to the ring center axis seen a reduced material strength.

The indentation is preferably at least approximately slot-shaped, arrowhead-shaped, V-shaped, oval, elliptical, triangular, rectangular, pentagonal or hexagonal.

Preferably, a guide element has a plurality of connecting portions, which have indentations whose shape is identical in each case. But it can also be provided that the indentations of the connecting portions are configured in different forms.

Preferably, the at least one connecting portion comprises a recess which, in the axially clamped state of the guide element, permits material expansion inwardly and / or within the guide element.

It may be favorable if the connecting portion comprises a recess, which is arranged in a central region and / or in the central region of the base body.

In particular, the central area does not comprise the edge sections of the base body, for example no axial projections and / or no axial recesses.

Additionally or alternatively it can be provided that the main body of the guide element comprises indentations, which form an edge portion as axial recesses.

In addition or as an alternative to indentations, it can be provided that the at least one connecting section comprises at least one passage opening.

In embodiments in which the connecting sections comprise indentations and passage openings, an escape area is preferably created by the indentations, and a further escape area is arranged in particular in an interior space of the passage openings.

The passage openings break through the base body, in particular in the direction of the radial direction of the ring center axis. The passage opening is preferably at least approximately slot-shaped, arrowhead-shaped, V-shaped, oval, elliptical, triangular, rectangular, pentagonal or hexagonal.

The at least one connecting section preferably comprises at least one deformation section which is arranged between two contact surfaces which are opposite one another in the axial direction and offset or offset in the direction of rotation and which deflects and / or absorb forces resulting from an expansion of the guide element in the clamped state of the guide element.

In regions of the at least one deformation section of the connecting section, in the clamped state under tension, for example due to thermal expansion of the guide element, it is preferable to deflect and / or absorb the acting forces.

With thermal material expansion of the main body of the guide element, thermal expansion of material at the molecular level preferably occurs in the region of the at least one deformation section.

Due to the preferably acting in the axial direction of mechanical stress, in particular compressive stress, a force acts between the mutually in the axial direction opposite edges, in particular the opposite each other in the axial direction of contact surfaces.

Due to the thermal material expansion at the molecular level in the clamped state in the region of the at least one deformation section, the force acting in the axial direction is in particular deflected and there is a material expansion which is absorbed by the one or more escape areas.

By an increase in volume of the guide element resulting from an increase in temperature in an area formed by the escape areas. cavities, preferably, the opposing contact surfaces in the axial direction axially not further apart.

In particular, it comes in the clamped state during operation of the piston device to a thermal expansion in the region of the indentations, for example in the region of the escape areas, the connecting portions.

A coefficient of linear expansion α (alpha) in the region of the indentations is preferably proportional to a temperature change ΔΤ (delta T) under thermal load.

The expansion into areas of the indentations, in particular into the escape areas, is in particular reversible.

The deformation section is preferably arranged in the direction of rotation substantially between two contact surfaces lying opposite one another in the axial direction and / or a contact surface and a recess.

The at least one connecting portion preferably comprises a recess and / or passage opening, which has a main extension direction, which is oblique or parallel to a tangent applied to the circumferential direction of the main body.

"Oblique" preferably means that the recesses in the respective main extension direction do not enclose an angle of approximately 180 °, of approximately 90 ° or of approximately 0 ° with the tangent applied to the direction of circulation of the main body.

In particular, the guide element comprises a plurality of connecting portions each having a recess, wherein the connecting portions are in particular arranged such that their indentations are arranged distributed uniformly in the direction of rotation of the body. Preferably, the base body has one or more rows of indentations, which run in each case in particular along the circumferential direction.

In the one or more rows of indentations, the indentations are preferably arranged distributed uniformly seen in the direction of rotation.

In particular, the indentations in the one or more rows of indentations are each arranged at least approximately at the same distance from each other as viewed in the direction of rotation.

It can be provided that the one or more rows of recesses in the direction of rotation each having a plurality of sections, wherein in each case a different arrangement of indentations than in a seen in the circumferential direction subsequent section.

It may be favorable if the indentations in the axial direction and / or in the circumferential direction are in each case offset with respect to one another in the case of several rows of indentations.

It can be advantageous if the guide element comprises at least one holding element which is arranged completely or partially on a radially inner side of the guide element and extends radially from the base body in the direction of the annular central axis.

In the assembled state of the piston, the retaining element is preferably in engagement with a retaining element receptacle, for example a retaining groove, of the piston. In particular, the holding element protrudes in the assembled state of the piston into a retaining element receptacle of the piston.

This may preferably offer the advantage that the guide element can be fixed to the piston at least approximately radially, axially and / or non-displaceably in the direction of rotation. It may be favorable if the holding element is designed as a holding web.

The retaining element preferably extends over the entire axial extent of the guide element with respect to the annular central axis.

The main body of the guide element is preferably at least approximately annular portion-shaped and has two open ends.

The at least approximately annular portion-shaped base body of the guide element preferably comprises approximately 60 ° or more of a circular ring in a cross section taken perpendicular to the annular central axis.

The at least approximately annular portion-shaped base body of the guide element preferably comprises in a taken perpendicular to the annular central axis cross-section about 80 ° or more of a circular ring.

For example, the basic body of the guide element formed at least approximately in the form of a ring section comprises approximately 100 ° or more of a circular ring.

The at least approximately annular portion-shaped base body of the guide element preferably comprises in a taken perpendicular to the ring center axis cross-section about 220 ° or less of a circular ring.

The at least approximately annular portion-shaped base body of the guide member preferably comprises in a taken perpendicular to the annular central axis cross-section about 180 ° or less of a circular ring.

For example, the base body of the guide element, which is formed at least approximately in the form of a ring section, comprises approximately 120 ° or less of a circular ring. It can be provided that an open end or both open ends have a projection or recess, which engages in the mounted state of the piston, in particular in a complementary thereto formed recess or projection on a piston skirt of the piston and / or locks.

For example, the two open ends form a mounting safeguard and / or have in particular a clip function for clipping onto the piston skirt.

Protrusions and / or recesses formed at an open end of a basic body of the guide element that is formed at least approximately in the form of a ring section are preferably radial projections and / or projections. The radial projections and / or radial recesses are, in particular, different projections and / or recesses from the axial projections and / or the axial recesses.

Preferably, both open ends of an at least approximately annular portion-shaped base body of the guide element on a projection or recess, which engages respectively in the assembled state of the piston in a complementarily designed for this recess or projection on a piston skirt of the piston and / or locks.

The guide element preferably comprises or is formed from one or more of the following polymers: polyetheretherketone (PEEK), polyamide (PA), polyimide (PI), polyoxymethylene (POM), polyphthalamide (PPA), polyester, vinylester, hard-tissue polymer, in particular Phenol base, polyester base and / or vinyl ester base, polyphenylene sulfide (PPS) and fluoropolymer, especially perfluoroalkoxy polymer (PFA), melt processible

Polytetrafluoroethylene (PTFE) polymer and polytetrafluoroethylene (PTFE). It may be favorable if the guide element comprises or is formed from a thermoplastic polymer.

Additionally or alternatively it can be provided that the guide element comprises or is formed from a thermosetting polymer.

For example, the guide element is formed from a polymer compound comprising a high-performance polymer and a different fully fluorinated thermoplastically processable polymer in a homogeneous distribution.

The fully fluorinated thermoplastically processable polymer comprises, in particular, a melt-processable PTFE polymer and / or perfluoroalkoxy polymer.

For example, the polymer compound may be under the product name

Moldflon® are purchased from ElringKlinger Kunststofftechnik GmbH.

The guide element in particular comprises an epoxy resin

Vinylesterharz, a polyester resin or a phenolic resin. Alternatively or additionally, the guide element made of an epoxy resin, a

Vinylesterharz, a polyester resin or a phenolic resin formed.

Preferably, the guide member comprises or is formed from a liquid crystal polymer. The liquid crystal polymer includes, in particular, polyaramides.

The guide element, in particular the plastic material of the

Guide element, preferably comprises at least 10 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular

hexagonal boron nitride. The guide element, in particular the

Plastic material of the guide element, in particular comprises at least 20 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, Polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element, in particular the plastic material of the

Guide element, preferably comprises at most 50 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride. The guide element, in particular the

Plastic material of the guide element, in particular comprises at most 40 wt .-% graphite, glass fibers, aramid fibers, carbon fibers,

Polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element, in particular the plastic material of the

Guide element, preferably comprises at least 5 vol .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride. The guide element, in particular the

Plastic material of the guide element comprises at least 10 vol .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element, in particular the plastic material of the

Guide element, preferably comprises at most 40 vol .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element preferably comprises a polyetheretherketone (PEEK) and 5 to 15% by weight of graphite, 5 to 15% by weight of polytetrafluoroethylene (PTFE) and / or 5 to 15% by weight of carbon fibers. The guide element comprises in particular a polyetheretherketone (PEEK) and at least approximately 10% by weight of graphite, at least

approximately 10% by weight polytetrafluoroethylene (PTFE) and / or at least approximately 10% by weight carbon fibers.

It may be favorable if the guide element, in particular the

Plastic material of the guide element, below one

Glass transition temperature, in particular below one

Glass transition temperature of the plastic material of the guide element, a coefficient of linear expansion in the range of 40 ^■ 10 ^Λ -6 Κ ^Λ -1 to 80 ^■ 10 ^Λ -6 Κ ^Λ -1, preferably in the range of 45 ^■ 10 ^Λ -6 Κ ^Λ -1

up to 70 ^· 10 ^Λ -6 Κ ^Λ -1, in particular in the range of 48 ^· 10 ^Λ -6 Κ ^Λ -1

to 68 ^■ 10 ^Λ -6 Κ ^Λ -1.

Preferably, the guide element, in particular the

Plastic material of the guide element, above a

Glass transition temperature, in particular above one

Glass transition temperature of the plastic material of the guide member, a coefficient of linear expansion in the range of 100 10 -6 ^Λ Κ ^Λ -1-200 ^■ 10 ^■ ^Λ -6 Κ ^Λ -1, preferably in the range of 45 10 ^■ ^Λ -6 Κ ^Λ -1

to 68 ^■ 10 ^Λ -6 Κ ^Λ -1.

Preferably, therefore, thermal expansions of a piston and / or a piston receptacle of a piston device can be compensated so that, in particular, an at least approximately constant piston clearance or a piston clearance increasing with increasing temperature can be achieved.

It may be favorable if the guide element is produced in an injection molding process and / or by machining. The guide element according to the invention is particularly suitable for use in a piston device, for example a dry-running piston device.

The present invention therefore also relates to a piston device, in particular a piston compressor.

The piston device preferably comprises a cylindrical piston receptacle for receiving a piston and a piston which is mounted linearly displaceable in the piston receptacle.

The piston preferably comprises a piston bottom for receiving and / or generating pressure forces. In particular, the piston comprises a bolt receptacle for receiving a piston pin.

The piston preferably comprises a piston skirt for force transmission between the piston crown and the bolt receptacle, wherein the piston skirt in particular has an at least approximately cylindrical or cylindrical section-shaped lateral surface in which one or more depressions are arranged, which are at least approximately ring-shaped or ring-shaped about a longitudinal central axis Extend lateral surface.

The piston device preferably comprises one or more guide elements for guiding the piston in the piston device, in particular guide elements according to the invention, wherein at least one guide element of the one or more guide elements extends in at least one of the recesses.

The one or more recesses are in particular formed as grooves.

In particular, the one or more recesses are formed as a receiving track, along which a ring-shaped guide element at can slide along the mounting, in particular such that an axial displacement of one or more open ends of the guide element with respect to the longitudinal center axis of the lateral surface can be avoided.

It may be favorable if the one or more depressions each comprise a contact surface for supporting the guide element, which is arranged at least approximately coaxially with the outer lateral surface of the piston.

At least one or more guide elements are preferably formed as a sliding element. In particular, all guide elements are designed as sliding elements.

Preferably, the one or more recesses of the piston of the piston device each have two flanks which are aligned at least approximately perpendicular to the longitudinal central axis of the lateral surface and at which edge portions, in particular contact surfaces of the one or more guide elements rest and / or are held under tension.

Preferably, edge portions, in particular contact surfaces, of the one or more guide elements are pressed in between the two flanks of the one or more recesses.

Preferably, the one or more guide elements are held under bias, in particular elastic bias, between the two flanks of the one or more recesses.

A due to the, in particular elastic, bias acting force acts in particular perpendicular to the direction of rotation of the guide elements.

It may be favorable if a thermal expansion of the guide element can take place without causing increased friction between the guide element and the guide element. The guide element and piston receiving comes and / or the guide element breaks due to excessive voltage and / or at least partially jumps out of the recess.

The piston preferably includes a recess extending across one or more recesses.

In particular, the recess is open to the side facing away from the piston crown side.

In unmounted and ready for use condition and / or in mounted

State of the piston device preferably have two axially opposite contact surfaces of the guide element an axial distance of about 85% or more of an axial distance of two opposite flanks of the recess in which the guide member extends.

Preferably, two contact surfaces of the guide element that are opposite one another in an axial direction in an unassembled and ready-to-use state and / or in an assembled state have an axial distance of approximately 95%, for example 98% or more, of an axial distance of two opposite flanks of the depression. in which the guide element extends.

It may be favorable if two contact surfaces of the guide element in an axial direction in the unassembled state have an axial distance of at most 110% of an axial distance from two opposite flanks of the recess, in which the guide element extends in the clamped state.

It may be favorable if two opposing contact surfaces of the guide element in the unassembled state have an axial distance of at most 105% of an axial distance of two opposite one another. have the flanks of the recess in which the guide element extends in the clamped state.

This may preferably offer the advantage that the guide element is clamped and / or held essentially axially free of play between the two flanks of the depression.

In one embodiment of the piston device is provided that the piston comprises a first metallic material or is formed from a first metallic material, wherein the piston seat in a

Plunger receiving body is arranged, which comprises a second metallic material or is formed from a second metallic material, wherein the first metallic material has a lower thermal

Expansion coefficient than the second metallic material.

It may be favorable if the piston receptacle is a particular

cylindrical wall comprises.

The wall of the piston receptacle comprises in particular an aftertreated surface.

The aftertreated surface of the wall of the piston receptacle is, for example, anodized and in particular comprises aluminum oxide. Alternatively or additionally, the aftertreated surface of the wall comprises a coating comprising nickel and silicon carbide.

The piston receptacle, in particular the cylinder, is preferably introduced into the piston receiving body, in particular into a cylinder housing, for example by drilling or milling;

The piston receiving body, in particular the cylinder housing, preferably forms the wall of the piston receptacle. The piston receiving body is in particular made of the second metallic material. The second metallic material comprises in particular a

Aluminum alloy or is made by an aluminum alloy.

The first metallic material comprises in particular steel, stainless steel and / or titanium or is formed by steel, stainless steel or titanium.

The second metallic material preferably has one

Coefficient of linear expansion in the range of 18 ^■ 10 ^ -6 Κ ^Λ -1

to 23 ^■ 10 ^Λ -6 Κ ^Λ -1, in particular in the range of 19 ^· 10 ^Λ -6 Κ ^Λ -1

to 23 ^■ 10 ^Λ -6 Κ ^Λ -1, more particularly in the range of 20 ^■ 10 ^ -6 Κ ^Λ -1 to 22 ^■ 10 ^Λ -6 Κ ^Λ -1.

The first metallic material preferably has one

Coefficient of linear expansion in the range of 8 ^■ 10 ^ -6 Κ ^Λ -1

to 16 ^■ 10 ^Λ -6 Κ ^Λ -1.

A wall of the piston receptacle and the piston, in particular guide elements arranged on the piston, are preferably spaced apart in the radial direction of a longitudinal central axis of the piston receptacle.

A radial distance of the wall of the piston seat and the piston, in particular the guide elements arranged on the piston, is in

Within the scope of this description and the appended claims, it is referred to as a piston play.

The one or more guide elements of the piston device preferably have an average radial material thickness.

An average radial material thickness of a guide element is in particular an average material strength of the guide element in the radial direction of a ring center axis of the guide element. An average radial thickness of one or more guide elements is in particular selected such that a piston play or a radial distance of a wall of the piston receptacle and of the piston, in particular of guide elements arranged on the piston, in

Dependence of an increasing operating temperature of the piston device is at least approximately constant or increases.

Preferably, a jamming of the piston in the piston seat can thus be prevented even at high operating temperatures.

Preferably, an average radial material thickness of the one or more guide elements is in accordance with a ratio of

Linear expansion coefficients of the first and second metallic materials selected.

Preferably, by the one or more guide elements different expansions of piston and piston seat can be compensated. In particular, the piston clearance increases with increasing

Temperatures or remains at least approximately constant.

Preferably, the guide element has an average radial

Material thickness in the ratio of 0.03: 1 to 0.07: 1, in particular in the ratio of 0.04: 1 to 0.06: 1, to a diameter of the piston seat and / or the piston on.

In the context of this description and the appended claims, a diameter of the piston receptacle and / or of the piston is understood in particular to mean a diameter of the piston receptacle and / or of the piston taken perpendicular to a longitudinal axis of the piston receptacle and / or the piston.

The present invention further relates to a method for producing a guide element, in particular a guide element according to the invention. The invention is in this respect the task of providing a method for producing a guide element, by means of which a simply constructed and a piston efficiently leading guide element can be produced.

This object is achieved according to the invention in that the method for producing a guide element, in particular a guide element according to the invention, comprises the following:

Provision of a base body of the guide element, which is at least approximately annular or ring-section-shaped and which extends in a circumferential direction at least approximately annular or ring-shaped portion about a ring center axis.

Providing and / or generating at least one connecting portion for elastic and / or flexible connection of edge portions of edges of the base body, which in a direction parallel to the annular central axis extending axial direction opposite each other.

The method according to the invention preferably has one or more of the features and / or advantages described in connection with the guide element according to the invention.

At least one connecting section is preferably produced during production and / or provision of the basic body.

It may be favorable if initially the main body of the guide element is provided and subsequently at least one connecting section is produced. For example, the main body of the guide element is provided, and then the at least one connecting section is produced and / or introduced in a post-processing step.

During and / or for providing and / or generating the at least one connecting portion, at least one indentation is preferably introduced into the main body of the guide element.

Alternatively it can be provided that the base body and the at least one connecting portion are provided in one step, for example by injection molding.

Further preferred features and / or advantages of the invention are the subject of the following description and the drawings of exemplary embodiments.

In the drawings show:

Fig. 1 is a schematic side view of a first embodiment

a piston of a piston device, in which a piston skirt is provided with two guide elements according to a first embodiment of a guide element, each comprising a plurality of connecting portions;

Fig. 2 is a schematic perspective view of a portion of

First embodiment of a guide element in the unrolled state, in which the behavior in thermal expansion of material in the clamped state shown in FIG. l is indicated by dashed lines;

3 shows a schematic side view of a section of the first embodiment of a guide element in the unrolled state; a schematic perspective view of the first embodiment of a guide element in the rolled state about a ring center axis, wherein an at least approximately annular shape of a base body of the guide element is closed except for a slot between two open ends of the base body; a schematic perspective view of a portion of a second embodiment of a guide element in the unrolled state, the connecting portions connect edge portions in the form of axial projections and axial recesses, wherein the axial projections at one edge as rounded projections and at the axially opposite edge as plateau projections are trained; a schematic side view of a portion of the second embodiment of a guide member in the unrolled state; a schematic perspective view of the second embodiment of a guide member in the rolled-up state, in which the guide element comprises on its radially inner inner side a holding element which extends in the radial direction of the annular central axis to the annular central axis; a taken perpendicular to a longitudinal central axis of a lateral surface of a piston skirt schematic cross section through the second embodiment of a guide element in a clamped state in a piston; a schematic cross-section taken perpendicular to the ring center axis of a third embodiment of a guide element in the rolled-up state, in which the base body is annular-section-shaped and has two open ends, each having a recess extending inward in the radial direction;

10 is a taken perpendicular to the ring center axis schematic

Cross-section of a fourth embodiment of a guide element in the rolled-up state, in which the base body is annular-section-shaped and comprises on its radially inner inner side a holding element which projects inward in the radial direction;

11 shows a schematic perspective view of a fifth embodiment of a guide element in the rolled-up state, which comprises a ring-shaped base body which comprises indentations extending at an angle on its radially outer outer side to the annular central axis;

Fig. 12 is a schematic side view of a section of a sixth

Embodiment of a guide element in the unrolled state, in which two mutually axially opposite edges of the base body each comprise axial projections and recesses, which are seen alternately arranged in the direction of rotation;

Fig. 13 is a schematic side view of a seventh embodiment

a guide element in the unrolled state, in which the connecting portions of the base body along the circumferential direction extending through openings comprise;

14 shows a schematic side view of a section of an eighth embodiment of a guide element in the unrolled state, in which the connecting sections of the base body comprise passage openings extending at an angle to the circulation direction and at least approximately triangular passage openings; Fig. 15 is a schematic perspective view of a piston device, wherein the piston according to a second embodiment of a piston on its lateral surface comprises a recess which extends over a plurality of ring-shaped depressions in the lateral surface of time.

Identical or functionally equivalent elements are provided with the same reference numerals in all figures.

An in Fig. 1 piston 100 is preferably part of a generally designated 102 piston device, in particular a compressor device for generating pressurized gases.

The piston device 102 comprises, in addition to the piston 100, a cylindrical piston receptacle 104 for receiving the piston 100. Preferably, the piston 100 is mounted so as to be linearly displaceable in the piston receptacle 104.

The piston receptacle 104 is in particular a cylinder. The piston receptacle 104 is preferably introduced into a piston receiving body 105, in particular into a cylinder housing 107, for example by drilling or milling.

The piston receptacle 104 preferably has a diameter 109, in particular an inner diameter. The diameter 109 of the

Piston receptacle 104 is in particular a perpendicular to a longitudinal axis of the piston receiving 104 taken diameter.

The piston receptacle 104 comprises an in particular cylindrical wall 111. The piston accommodating body 105 preferably forms the wall 111 of the piston receptacle 104.

The wall 111 of the piston receptacle 104 in particular comprises an aftertreated surface. The aftertreated surface of the wall 111 of the piston receptacle 104 is, for example, anodized and comprises in particular aluminum oxide. Alternatively or additionally, the aftertreated surface of the wall 111 comprises a coating comprising nickel and silicon carbide.

The piston 100 preferably includes a piston bottom 106 for receiving and / or generating compressive forces which limits the piston 100 at one end.

The piston head 106 is preferably arranged facing a pressure chamber 108 of the piston device 102 during operation of the piston device 102 and, in particular, comes into direct contact with pressurized operating gases or pressurized operating gases.

The piston head 106 is in particular at least approximately designed as a flat circular cylinder.

The piston 100 comprises a bolt receptacle 110 for receiving a piston pin 112. By means of the piston pin 112, the piston 100 is preferably fixed to a connecting rod. The connecting rod is mounted in particular on a crankshaft.

By means of the piston pin 112 and the connecting rod, the piston 100 is preferably connected to the crankshaft.

To seal the pressure chamber 108 in the direction of the crankshaft in particular a seal is required.

This seal can be made possible for example by a piston ring. Such a piston ring is in particular a component which is arranged in a piston ring groove 114 of the piston 100. The piston 100 preferably includes a piston skirt 116 for transmitting power between the piston crown 106 and the bolt receiver

110th

The piston skirt 116 is preferably at least approximately cylindrical or cylindrical-section-shaped and has an at least approximately cylindrical or cylinder-shaped lateral surface 118.

In the at least approximately cylindrical or cylindrical section-shaped lateral surface 118 of the piston skirt 116, one or more depressions 120 are arranged, which extend at least approximately annularly or annularly around a longitudinal center axis 122 of the lateral surface 118 of the piston skirt 116.

Preferably, the piston 100 comprises or is formed from a first metallic material 123.

For example, the piston 100 is manufactured in a 3D printing process.

The piston receptacle 104, in particular the piston receiving body 105, preferably comprises a second metallic material 125 or is formed therefrom.

It can be provided that the piston 100 and the piston receptacle 104 comprise mutually different materials or are formed from different materials.

Preferably, the first metallic material 123 has a lower thermal expansion coefficient than the second metallic material 125. The first metallic material 123 comprises in particular steel, stainless steel and / or titanium or is formed by steel, stainless steel or titanium.

The second metallic material 125 comprises in particular a

Aluminum alloy or is made by an aluminum alloy.

The second metallic material 125 preferably has one

Coefficient of linear expansion in the range of 18 ^■ 10 ^Λ -6 Κ ^Λ -1

up to 23 ^· 10 ^Λ -6 Κ ^Λ -1, in particular in the range of 19 ^· 10 ^Λ -6 Κ ^Λ -1 to 23 ^· 10 ^Λ -6 Κ ^Λ -1, more particularly in the range of 20 ^· 10 ^Λ -6 Κ ^Λ -1 to 22 10 ^■ ^Λ -6 Κ ^Λ -1.

The first metallic material 123 preferably has one

Coefficient of linear expansion in the range of 8 ^■ 10 ^Λ -6 Κ ^Λ -1

to 16 ^■ 10 ^Λ -6 Κ ^Λ -1.

Preferably, the piston device 102 comprises one or more guide elements 124 for guiding the piston 100 in the piston device 102.

It may be favorable if in each case a guide element 124 is arranged in a recess 120 of the lateral surface 118 of the piston skirt 116.

The one or more depressions 120 are formed, for example, as grooves, in particular annular grooves.

It may be favorable if the one or more recesses 120 each have two flanks 126.

The two flanks 126 of the recess 120 preferably extend at least approximately coaxially with one another. In particular, the two flanks 126 of the recesses 120 extend at least approximately in a radial direction of the longitudinal central axis 122 away from the lateral surface 118.

It can be advantageous if in each case a bearing surface 128 for supporting the guide element 124 extends between the two flanks 126 of the depressions 120.

Preferably, the support surface 128 of the recess 120 is at least approximately coaxial with the lateral surface 118 of the piston skirt 116.

Two edges 130 of the one or more guide elements 124 that are axially opposite each other with respect to the longitudinal central axis 122 preferably include a plurality of edge sections 132.

The edge portions 132 are preferably formed as axial projections 134 and / or axial recesses 136.

The axial projections 134 preferably extend in the axial direction 146 at a maximum distance from a central region 135 of the guide element 124.

The middle region 135 preferably lies at least approximately in the middle between the average extent of the edges 130 in the axial direction 146.

The middle region 135 is indicated in some figures in the unrolled state with a dashed line of alternately longer and shorter strokes.

It may be favorable if an edge 130 of the two axially opposite edges 130 of the guide element 124 is formed from axial projections 134 arranged in the circumferential direction 138 and axial recesses 136. In Figs. 2 to 4 are cutouts of FIG. 1 in a clamped and / or assembled state illustrated first embodiment of a guide member 124 shown in different views.

The guide element 124, as can be seen in particular in FIG. 4, in the rolled-up and / or clamped state preferably has an at least approximately annular base body 140 which extends at least approximately annularly in a circumferential direction 138 relative to a ring center axis 142.

Preferably, the base body 140 forms at least approximately a ring, in particular at least approximately a circular ring, about the ring central axis 142.

The guide element 124 preferably comprises at least one connecting portion 144 for the elastic and / or flexible connection of edge portions 132 of edges 130 of the base body 140, which face each other in an axial direction 146 extending parallel to the annular central axis 142.

Preferably, two edge portions 132 opposite each other in the axial direction 146 are resiliently and / or elastically connected to each other by a connecting portion 144.

The guide element 124 may be formed as a piston ring or piston ring portion.

Preferably, however, the guide member 124 is one of a

sealing piston ring different element.

In particular, the guide element 124 is designed as a guide band and / or flat material. In rolled-up and / or clamped state of the guide element 124, the guide element 124 is bent in particular around the ring center axis 142 and / or curved.

The ring central axis 142 of the main body 140 is preferably substantially identical to the longitudinal central axis 122 of the piston 100.

The ring central axis 142 forms, in particular, an axis of rotation with respect to the circumferential direction 138 of the main body 140.

Preferably, the axial projections 134 project away from the middle region 135 of the base body 140 in the axial direction 146. Between two axial projections 134, in particular an axial recess 136 is arranged in the circumferential direction 138 on an edge 130.

The axial recesses 136 preferably protrude in the axial direction 146 away from the central region 135 of the main body 140.

A surface bounding an axial projection 134 in the axial direction 146 forms, in particular, a contact surface 148.

The contact surfaces 148 rest in the clamped state of the guide element 124, in particular on the flanks 126 of the depressions 120.

A radially inner side 163 of the base body 140 of the guide element 124 is in the clamped state preferably directly on the support surface 128 of a recess 120 and / or on.

The axial projections 134, which are delimited by the contact surface 148 in the axial direction 146, extend locally, preferably in the axial direction 146, locally at a maximum distance from the central region 135 of the base body 140. The axial recesses 136 have in particular a minimum axial distance to the central region 135.

In the clamped state of the guide element 124 is in particular completely or partially a direct contact between the at least one contact surface 148 and at least one of the two edges 126 of the recesses 120th

It may be favorable if the at least one contact surface 148 in the clamped state of the guide element 124 is completely or partially in material contact with the two flanks 126 of the recesses 120 of the piston 100.

With respect to the direction of rotation 138, two contact surfaces 148 arranged on opposite edges 130 of the guide element 124 are preferably offset relative to one another.

Preferably, the contact surfaces 148 in the clamped or rolled-up state at least approximately a circular ring segment shape. Non-curved surfaces of the at least approximately annular segment-shaped contact surfaces 148 are arranged in particular in a plane extending substantially perpendicular to the ring center axis 142.

It may be favorable if the axial projections 134 are formed as plateau projections 149.

Preferably, the at least one connecting portion 144 comprises a recess 150, through which in the axially clamped state of the guide member 124, an escape region 151 is formed. In particular, the escape area 151 forms a free space for receiving a partial volume of the guide element 124, around which the guide element 124 increases due to thermal expansion. Preferably, the free space accommodates a partial volume of the guide element 124, which due to the inserted tensioned state of the guide member 124 in the region of the contact surfaces 148 can not expand in the axial direction 146, but rather is displaced into the escape area 151 into it.

Preferably, the axial distance between two mutually opposed in the axial direction 146 contact surfaces 148 due to the inclusion of a partial volume of the guide member 124 of the space formed by the escape areas 151 remains at least approximately constant despite the increase in temperature.

In particular, the material expansion of the guide element 124 is limited at least approximately to the expansion into the escape regions 151 when the temperature increases.

In the region of the escape regions 151, during the operation of the piston device 102, a deformation of the base body 140 preferably occurs.

In Fig. 2 and 3, the behavior of the guide elements 124 in the clamped state under thermal stress, for example at temperatures of 100 ° C or more, shown by dashed lines.

Due to the evasion regions 151 created by the indentations 150, in particular a temperature-induced material expansion in the direction of a radial direction of the annular central axis 142 from the main body 140 to the outside is minimized.

In the region of the indentations 150, the base body 140 preferably has a reduced material thickness parallel to the ring center axis 142 in comparison to areas of the base body 140 without indentation 150.

In particular, the indentations 150 are part of the axial recesses 136 or form the axial recesses 136. The material thickness of the base body 140 in areas of the indentation 150 is preferably approximately 80% or less of the material thickness of the base body 140 in areas without indentation 150.

In particular, the material thickness of the base body 140 in areas of the recess 150 is about 60% or less of the material thickness of the base body 140 in areas without recess 150th

For example, the material thickness of the base body 140 in areas of the recess 150 is about 40% or less of the material thickness of the base body 140 in areas without recess 150th

Preferably, the guide element 124, in particular a base body 140 of the guide element 124, an average radial material thickness 153 in the radial direction, i. in a direction perpendicular to the ring central axis 142, on.

It may be favorable if the connecting sections 144 of the guide element 124 each comprise at least one deformation section 152, which is arranged between two opposing contact surfaces 148 and / or edge sections 132.

The at least one deformation section 152, in particular in the clamped state of the guide element 124, deflects forces resulting from an expansion and / or absorbs them.

For example, a contact surface 148 absorbs mechanical stresses which are deflected in the region of the deformation section 152, in particular in such a way that they extend into the region of the indentations 150, for example into the escape regions 151.

In the clamped state, a force in the axial direction 146 preferably acts on the base body 140 of the guide element 124. Preferably, in the clamped state, a mechanical stress, in particular a compressive stress, acts on the guide element 124.

It may be favorable if mechanical stresses resulting from thermal expansion in the clamped state are preferably deflected by means of the connecting sections 144, in particular by means of the deformation sections 152.

Due to thermal material expansion in the region of the deformation sections 152, the forces acting in the axial direction 146 are preferably deflected and / or absorbed.

The deflection and / or absorption is realized in particular by temperature-induced expansion at the molecular level in the region of the deformation sections 152.

The temperature-induced expansion at the molecular level in the region of the deformation sections 152 is preferably not perceptible to the eye.

By means of the connecting portions 144, in particular by material expansion into the escape regions 151 created by the indentations 150, an axially maximum extent of the guide elements 124, which is at least approximately constant in a clamped state, is possible.

During operation of the piston device 102, the base body 140 preferably expands into the free space formed by the escape regions 151, in particular in such a way that the axial distance between contact surfaces 148 of the guide element 124 lying opposite one another in the axial direction 146 remains substantially constant. In Fig. 4, in particular, it can be seen that the base body 140 has a slot 155 which is formed between two open ends 154 of the base body 140.

In the clamped state of the guide element 124 preferably the two open ends 154 of the base body 140, in particular their respective end edges 156, adjoin one another.

Alternatively, it may be provided that the two open ends 154 in the clamped state of the guide element 124 in the circumferential direction 138 have a distance from each other, which substantially corresponds to at least the axial distance between two edges 126 of the recess 120 of the piston 100 in the axial direction 146.

Furthermore, the distance between the two open ends 154 of the guide element 124 may be at least approximately or at least as follows:

a) a material thickness of the guide element 124 in the radial direction;

b) a height of the flanks 126 (extension of the flanks 126 in the radial direction); and or

c) a width of the guide element 124 in a direction parallel to the annular central axis 142 direction.

For example, the distance between the two open ends 154 of the

Guide element 124 in the circumferential direction 138 in a mounted

Initial state of the guide element 124 at ambient temperature at least about 1 mm, preferably at least about 2 mm, in particular at least about 3 mm.

The distance between the two open ends 154 of the guide element 124

preferably allows thermal expansion of the

Base body 140 in the circumferential direction 138. The slot 155 is arranged in particular at an angle to the ring central axis 142 and to the circumferential direction 138.

The end edges 156 of the two open ends 154 are preferably each formed obliquely to the circumferential direction 138 and the ring center axis 142 extending.

The end edges 156 are in particular formed complementary to one another.

For example, the end edges 156 of the two open ends 154 are formed by cut edges running obliquely to the direction of rotation 138 and to the ring central axis 142.

The end edges 156 preferably each include an obtuse angle, for example an angle of approximately 100 ° to approximately 170 °, with one of the two edges 130 of the base body 140.

In particular, the end edges 156 each subtend an acute angle, for example, about 20 ° to about 90 °, with the other of the two edges 130 a.

It may be favorable if the closing edges 156 are arranged at least approximately parallel to one another.

The guide element 124 preferably comprises a plastic material 157 or is formed from a plastic material 157.

In particular, the guide element 124 comprises or is formed from one or more of the following polymers: polyetheretherketone (PEEK), polyamide (PA), polyimide (PI), polyoxymethylene (POM), polyphthalamide (PPA), polyester, vinylester, hard-tissue polymer, in particular phenol-based, polyester-based and / or vinylester-based, polyphenylene sulfide (PPS) and Fluoropolymer, in particular perfluoroalkoxy polymer (PFA), melt-processable polytetrafluoroethylene (PTFE) polymer and polytetrafluoroethylene (PTFE).

Preferably, the guide member 124 comprises a thermoplastic

Polymer or is formed from it.

Additionally or alternatively, the guide element 124 in particular comprises a thermosetting polymer or is formed therefrom.

For example, the guide element 124 comprises or is formed from Moldflon®.

The guide element 124 comprises, in particular, an epoxy resin

Vinylesterharz, a polyester resin or a phenolic resin. Alternatively or additionally, the guide member 124 is formed of an epoxy resin, a vinyl ester resin, a polyester resin or a phenolic resin.

Preferably, the guide member 124 comprises or is formed from a liquid crystal polymer. The liquid crystal polymer 124 includes, in particular, polyaramides.

The guide element 124, in particular the plastic material 157 of the guide element 124, preferably comprises at least 10 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular

hexagonal boron nitride. The guide element 124, in particular the

Plastic material 157 of the guide element 124, in particular comprises at least 20 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element 124, in particular the plastic material 157 of the guide element 124, preferably comprises at most 50% by weight of graphite, Glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride. The guide element 124, in particular the

Plastic material 157 of the guide element 124, in particular comprises at most 40 wt .-% graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element 124, in particular the plastic material 157 of the guide element 124, preferably comprises at least 5% by volume of graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride. The guide element 124, in particular the

Plastic material 157 of the guide element 124 comprises at least 10% by volume of graphite, glass fibers, aramid fibers, carbon fibers,

The guide element 124, in particular the plastic material 157 of the guide element 124, preferably comprises at most 40% by volume of graphite, glass fibers, aramid fibers, carbon fibers, polytetrafluoroethylene (PTFE), mineral fillers and / or ceramic fillers, in particular hexagonal boron nitride.

The guide element 124 preferably comprises a polyetheretherketone (PEEK) and 5 to 15% by weight of graphite, 5 to 15% by weight of polytetrafluoroethylene (PTFE) and / or 5 to 15% by weight of carbon fibers.

The guide element 124 comprises in particular a polyetheretherketone (PEEK) and at least approximately 10% by weight of graphite, at least approximately 10% by weight of polytetrafluoroethylene (PTFE) and / or at least approximately 10% by weight of carbon fibers. It may be favorable if the guide element 124, in particular the plastic material 157 of the guide element 124, below a

Glass transition temperature, in particular below one

Glass transition temperature of the plastic material 157 of the guide member 124, a coefficient of linear expansion in the range of 40 ^■ 10 ^Λ -6 Κ ^Λ -1 to 80 ^■ 10 ^Λ -6 Κ ^Λ -1, preferably in the range of 45 ^■ 10 ^Λ -6 Κ ^Λ -1

to 68 ^■ 10 ^Λ -6 Κ ^Λ -1.

Preferably, the guide element 124, in particular the

Plastic material 157 of the guide element 124, above a

Glass transition temperature, in particular above one

Glass transition temperature of the plastic material 157 of the guide member 124, a coefficient of linear expansion in the range of 100 ^■ 10 ^Λ -6 Κ ^Λ -1 to 200 ^■ 10 ^Λ -6 Κ ^Λ -1, preferably in the range of 45 ^■ 10 ^Λ -6 Κ ^Λ -1 to 70 ^■ 10 ^Λ -6 Κ ^Λ -1, in particular in the range of 48 10 ^■ ^Λ -6 Κ ^Λ -1

to 68 ^■ 10 ^Λ -6 Κ ^Λ -1.

Thus, thermal expansions of a piston 100 and / or a piston receptacle 104 of a piston device 102 may preferably be provided

be compensated, so that in particular an at least approximately constant piston play or a piston with increasing temperature piston play can be achieved.

An average radial material thickness 153 of one or more

Guide elements 124 is particularly chosen such that a piston clearance or a radial distance of the wall 111 of the piston receptacle 104 and the piston 100, in particular arranged on the piston 100

Guide elements 124, in response to a rising operating temperature of the piston device 102 is at least approximately constant or increases. Preferably, jamming of the piston 100 in the piston receptacle 104 can thus be prevented even at high operating temperatures.

Preferably, an average radial material thickness 153 of the one or more guide elements 124 is selected according to a ratio of linear expansion coefficients of the first and second metallic materials 123, 125.

Preferably, 124 different expansions of piston 100 and piston seat 104 can be compensated by the one or more guide elements. In particular, the piston clearance increases at higher temperatures or remains at least approximately constant.

The guide element 124 preferably has an average radial material thickness 153 in the ratio of 0.03: 1 to 0.07: 1, in particular in the ratio of 0.04: 1 to 0.06: 1, to a diameter of the piston receptacle 104 and / or of the piston 100.

It may be favorable if the guide element 124 is produced in an injection molding process and / or by machining.

The in Fig. 5 to 8 illustrated second embodiment of a guide member 124 differs from the first embodiment essentially in that the base body 140 has at one edge 130 axial, plateau projections 149 and at the other edge 130 axial, rounded projections 162.

It may be favorable if the contact surfaces 148 of the rounded projections 162 in the clamped state in the axial direction 146 form a contact line or an abutment point on the flanks 126 of the recesses 120. The contact surfaces 148 of the plateau projections 149 form, in the clamped state in the axial direction 146, in particular a contact surface on the flanks 126 of the recesses 120.

The contact surfaces 148 of the plateau protrusions 149 are preferably larger in comparison to the contact surfaces 148 of the rounded protrusions 162.

Between the axial projections 134, in particular the plateau projections 149 and / or the rounded projections 162, axial recesses 136 in the form of indentations 150 are preferably arranged in the circumferential direction 138.

The indentations 150 preferably each include an elongated base indentation 161 viewed in the circumferential direction 138. In the circumferential direction 138, in each case centrally with respect to the base indentations 161, the indentations 150 comprise, in particular, an at least approximately V-shaped and / or arrowhead-shaped region 160.

The base indentation 161 and the at least approximately V-shaped and / or arrowhead-shaped region 160 together form, in particular, essentially a T-shape.

When formed in the form of rounded projections 162 axial projections 134 in the clamped state, a material and / or direct contact between the contact surfaces 148 and flanks 126 of the recesses 120 compared to the plateau projections 149 of a guide member 124 is minimized.

One of the two edges 130 opposite one another in the axial direction 146 preferably comprises a plurality of edge sections 132, which are seen alternately in the circumferential direction 138 as a rounded projection 162 and as a base recess 161 with an at least approximately V-shaped and / or arrowhead-shaped region 160. The other of the two edges 130 preferably has alternately a plateau projection 149 and a base indentation 161 with an at least approximately V-shaped and / or arrow-shaped area 160 seen in the circumferential direction 138.

Both edges 130 opposite one another in the axial direction 146 preferably have axial return projections 136 and axial projections 134, viewed alternately in the circumferential direction 138.

The two edges 130 opposite one another in the axial direction 146 are preferably offset relative to one another. In particular, a rounded projection 162 in the axial direction 146 is directly opposite an at least approximately V-shaped and / or arrowhead-shaped region 160.

It may be favorable if a tip of an at least approximately V-shaped and / or arrowhead-shaped region 160 points in the direction of a rounded projection 162, which lies opposite in the axial direction 146.

Preferably, a plateau projection 149 in the axial direction 146 has an indentation 150, in particular an at least approximately V-shaped and / or arrowhead-shaped region 160, directly opposite.

It can be advantageous if the tip of an at least approximately V-shaped and / or arrowhead-shaped region 160 points in the direction of a center of an axially opposite plateau projection 149.

The at least approximately arrowhead-shaped and / or V-shaped regions 160 preferably extend with their tips substantially as far as the central region 135. Preferably, a zig-zag pattern of the main body 140 essentially results from axial projections 134 and axial recesses 136.

In Fig. 6, the direction of the thermal recess and / or deformation in the clamped state is indicated by arrows.

In extension of the arrows, escape areas 151 are preferably arranged.

In Fig. In particular, it can be seen that the base body 140 preferably has a holding element 164 on an inner side 163, which is radially inward with respect to the ring central axis 142.

The holding element 164 is designed for example as a holding web 166 and in particular extends completely or partially along the axial direction 146 on the inner side 163.

As shown in particular in FIG. 8, the holding element 164, in particular the holding web 166, engages in a holding element receptacle 168 of the piston 100 in the assembled state. The holding element receptacle 168 is designed in particular as a retaining groove.

It may be favorable if the holding element 164 projects into the holding element receptacle 168.

In the assembled state of the piston 100, the retaining element 164 preferably prevents a displacement of the guide element 124 in the circumferential direction 138 of the base body 140.

Incidentally, the in Fig. 5-8 illustrated second embodiment of a guide member 124 with respect to structure and function with the in Fig. 1 to 4 illustrated first embodiment, so that on the

Description insofar reference is made. The third embodiment of a guide element 124 shown in FIG. 9 differs from that shown in FIG. 5-8 illustrated second embodiment of a guide member 124 substantially in that the guide member 124 is preferably formed according to the third embodiment, at least approximately annular portion-shaped.

The main body 140 of the guide element 124 preferably has two open ends 154.

In particular, the two open ends 154 have two radial projections 170 extending inwardly in the radial direction with respect to the ring central axis 142.

The at least approximately annular portion-shaped base body 140 of the guide element 124 preferably comprises in a direction perpendicular to the ring center axis 142 cross section about 90 ° to about 180 ° of a circular ring, in particular about 100 ° to about 150 ° of a circular ring.

For example, the base body 140 of the guide element 124, which is formed at least approximately in the form of a ring portion, comprises approximately 160 ° to approximately 200 ° of a circular ring in a cross section taken perpendicular to the ring central axis 142.

The radial projections 170 engage in the assembled state of the piston 100 in particular in complementary thereto formed recesses on the piston skirt 116 of the piston 100 a.

It may be favorable if the radial projections 170 engage at the two open ends 154 of the base body 140 of the guide element 124 in recesses complementary thereto for this purpose on the piston skirt 116 of the piston 100. Incidentally, the in Fig. 9 illustrated third embodiment of a guide member 124 with the in FIG. 5-8 illustrated second embodiment in terms of structure and function, so that on the

Description insofar reference is made.

The illustrated in Fig. 10 fourth embodiment of a guide member 124 differs from that shown in FIG. 9 essentially in that, in addition to radial projections 170, it also has a retaining element 164, as in the embodiment shown in FIG. 7 and 8 shown second embodiment. The radial projections 170 and the holding web 164 preferably each extend radially inward.

Incidentally, the in Fig. 10 illustrated fourth embodiment of a guide member 124 with the in FIG. 9 illustrated third embodiment in terms of structure and function, so that reference is made to their description in this regard.

The in Fig. 11 illustrated fifth embodiment of a guide member 124 differs from that shown in FIG. 10 illustrated essentially in that the base body 140 of the guide member 124 on its radially outer side 174 indentations 150, wherein one applied to a main extension direction

Tangent substantially obliquely to the annular central axis 142 and a tangent to the circumferential direction 138 extend tangent.

In the region of the obliquely extending indentations 150, the base body 140 preferably has a reduced material thickness perpendicular to the direction of rotation 138.

The obliquely extending recesses 150 are formed, for example, as grooves 176. The main body 140 preferably has axial projections 134 formed as rounded projections 162 on an edge 130.

The edge 130 facing this one edge 130 in the axial direction 146 is formed, in particular like the edges 130 described in connection with the first embodiment of a guide element 124, with plateau projections 149.

In both edges 130, the indentations 150 between the axial projections 134 are preferably substantially elongated in the circumferential direction 138.

Incidentally, the fifth embodiment shown in FIG. 11 coincides in structure and function with the fourth embodiment of a guide member 124 shown in FIG. 10, so that reference is made to the description thereof.

The sixth embodiment of a guide element 124 shown in FIG. 12 differs from that shown in FIG. 5 to 8 illustrated essentially in that the two mutually opposite in the axial direction 146 edges 130 of the guide member 124 each have the same sequence and shape of edge portions 132.

Both edges 130 have in the circumferential direction 138 each axial projections 134, in particular rounded projections 162, and axial recesses 136, in particular base indentations 161 with at least approximately arrowhead-shaped and / or V-shaped portions 160, in an alternating sequence.

Mutually in the axial direction 146 opposite axial projections 134 and axial recesses 136 are preferably offset from one another at the two edges 130. In the axial direction 146, each axial projection 134 is preferably directly opposite an axial recess 136.

Incidentally, the in Fig. 12 shown sixth embodiment of a guide member 124 with the in FIG. 5 to 8 shown second embodiment in terms of structure and function, so that reference is made to their description in this regard.

One in Fig. 13 illustrated seventh embodiment of a guide member 124 differs from the first embodiment shown in FIGS. 1 to 4 essentially in that the connecting portion 144 has substantially parallel to the circumferential direction 138 extending through openings 178.

The passage openings 178 are preferably arranged at a distance from the edges 130 of the base body 140.

The passage openings 178 are preferably at least approximately slot-shaped.

An interior of the passage openings 178 preferably forms one or more escape areas 151, which receive thermal expansion of the guide element partial volumes of the guide member 124 which extend from an edge region of the passage openings 178 inwardly.

Preferably, a clearance formed by the escape areas 151 occupies a volume of thermal expansion of material

Volume enlargement of the guide element 124.

The interior formed by the passage openings 178 preferably decreases due to thermal expansion of the material of the guide element 124 in the clamped state, whereby the axial distance between two opposite axial projections 134, in particular their contact surfaces 148, is kept substantially constant.

In particular, when the temperature increases in the clamped state, the guide element 124 extends into the escape areas 151 forming the interior of the passage openings 178 and / or expands into the escape areas 151, while the maximum axial distance of two edges 130 opposite each other in the axial direction 146, especially the contact surfaces 148, remains substantially constant.

It may be favorable if the guide element 124 comprises two rows of slot openings 178 arranged in parallel to each other, in particular slot-shaped.

In the rows, the passage openings 178 are arranged in the axial direction 146 and / or in the direction of rotation 138, in particular offset from one another.

Preferably, the edges 130 are each formed to be 60% or more, preferably 80% or more, more preferably 90% or more, of the axial projections 134.

Preferably, the edges 130 of the main body 140 seen in the circumferential direction 138 between two passage openings 178 of a series of passage openings 178 has an elongated axial recess 136.

The elongated axial recesses 136 in particular form indentations 150.

Incidentally, the in Fig. 13 illustrated seventh embodiment of a guide member 124 with the in FIG. 1 to 4 illustrated first embodiment in terms of structure and function, so that on the

Description insofar reference is made. One in Fig. 14 illustrated eighth embodiment of a guide member 124 differs from that shown in FIG. 13 illustrated substantially by the fact that the edges 130 are formed substantially coaxially with the circumferential direction 138. The connecting portions 144 comprise substantially slot-shaped passage openings 178 and substantially triangular passage openings 178.

A main extension direction of the substantially slot-shaped passage openings 178 is preferably arranged obliquely to the circulation direction 138 and to the ring central axis 142.

The substantially triangular passage openings 178 are preferably arranged such that their tips point alternately to the one and the other edge 130 of the two edges 130 opposite each other in the axial direction 146.

The at least approximately obliquely to the circumferential direction 138 extending substantially slit-shaped passage openings 178 are preferably arranged parallel to each other.

It may be favorable if the slot-shaped passage openings 178 are arranged substantially parallel to a leg of the triangular passage openings 178.

It may be favorable if the base body 140 has sections seen in the circumferential direction 138, which have slot-shaped passage openings 178. These sections are seen in the circumferential direction 138, in particular arranged alternately with sections with triangular passage openings 178.

Incidentally, the eighth embodiment of a guide element 124 shown in FIG. 14 is identical to the one shown in FIG. 13 illustrated seventh embodiment form in terms of structure and function, so that reference is made to their description in this respect.

One in Fig. The illustrated second embodiment of the piston 100 of the piston device 102 differs from the piston 100 shown in FIG. 1 essentially in that the lateral surface 118 comprises a recess 182, which preferably extends over a plurality of recesses 120.

The piston skirt 116 has, for example, three recesses 120.

In particular, the recess 182 is open to the side facing away from the piston head 106 side.

In Fig. In particular, it can be seen that the two flanks 126 of the depression 120 are preferably directly adjacent to the contact surface 128 of the depression 120.

In particular, the two flanks 126 of a depression 120 enclose an angle of approximately 70 ° to approximately 110 ° with the bearing surface 128.

It may be favorable if a guide element 124 is at least approximately ring-shaped in section and comprises two open ends 154 (cf., for example, FIGS. 9 to 11).

Preferably, the two open ends 154 each comprise a radial projection 170 which engages around and / or engages behind an edge 184 formed by the recess 182 (not shown).

For example, the radial projections 170 and the edges 184 are hooked together. It may be favorable if the piston 100 is arranged on a connecting rod 190 by means of the piston pin 112.

The connecting rod 190 is preferably mounted on a crankshaft 192.

By means of the piston pin 112 and the connecting rod 190 in particular a connection between the piston 100 and the crankshaft 192 is made.

The guide member 124 may be manufactured, for example, by the method described below.

Preferably, a base body 140 of the guide element 124 is provided, which is at least approximately ring-shaped or ring-section-shaped and which extends in a circumferential direction 138 at least approximately ring-shaped or ring-shaped around a ring central axis 142.

In particular, at least one connecting portion 144 is provided and / or generated which elastically and / or flexibly connects edge portions 132 of edges 130 of the base body 140.

The edge portions 132 of the edges 130 face each other in particular in an axial direction 146 extending parallel to the annular central axis 142.

Preferably, at least one connecting portion 144 is produced during manufacture and / or provision of the base body 140.

First of all, the base body 140 of the guide element 124 is preferably provided and / or produced and subsequently at least one connecting section 144 is produced. For example, the main body 140 of the guide element 124 is provided and / or produced, and subsequently, in a post-processing step, the at least one connecting section 144 is produced and / or introduced.

Alternatively, it may be provided that the base body 140 and the at least one connecting portion 144 are provided and / or manufactured together in one step, for example by injection molding.

It may be favorable if one or more indentations 150 are introduced during the production of the main body 140 or subsequently into the main body 140.

Characterized in that the guide elements 124 preferably comprise connecting portions 144 for elastic and / or flexible connection of edge portions 132 of edges 130, a play-free, for example, a substantially axially play-free, fixing the guide elements 124 on the piston 100 is possible even at varying temperatures.

In particular, increased frictional forces between the guide element 124 and the piston receptacle 104, jumping out of the guide element 124 from the recess 120 and / or creeping of the guide element 124 during operation even at varying temperatures can be avoided.

Claims

claims

A guide element (124) for a piston (100) of a piston device (102), wherein the guide element (124) comprises:

an at least approximately annular or ring-shaped base body (140) which extends at least approximately annularly or annularly in a circumferential direction (138) with respect to a ring central axis (142); and

at least one connecting portion (144) for the elastic and / or flexible connection of edge portions (132) of edges (130) of the base body (140), which in a direction parallel to the annular central axis (142) extending axial direction (146) face each other.

Second guide element (124) according to claim 1, characterized in that the guide element (124) has one or more projections (134) which project away from a central region (135) of the base body (140) to the outside and a part of the edge portions ( 132), wherein an axial surface (146) outer surface of the one or more protrusions (134) forms one or more contact surfaces (148).

3. Guide element (124) according to claim 1 or 2, characterized in that two mutually in the axial direction (146) opposite edges (130) of the base body (140) are each formed by a plurality of edge portions (132) which along the circumferential direction (138 ) are formed alternately as axial projection (134) and axial recess (136).

4. guide element (124) according to one of claims 1 to 3, characterized in that the at least one connecting portion (144) a recess (150), by which an escape region (151) is provided, in which the guide element (124) expands in a clamped state at a temperature increase, while the axial distance between two axially opposite contact surfaces (148) remains at least approximately constant ,

5. guide element (124) according to one of claims 1 to 4, characterized in that the at least one connecting portion (144) comprises a recess (150) which in the axially clamped state of the guide element (124) has a material expansion inwardly and / or within the guide element (124) allows.

6. guide element (124) according to one of claims 1 to 5, characterized in that the at least one connecting portion (144) comprises at least one passage opening (178).

7. guide element (124) according to one of claims 1 to 6, characterized in that the at least one connecting portion (144) comprises at least one deformation portion (152) which between two in the axial direction (146) opposite and in the circumferential direction (138) arranged offset or non-offset contact surfaces (148) is arranged and which in the clamped state of the guide element (124) from an extension of the guide element (124) deflects resulting forces and / or receives.

8. guide element (124) according to one of claims 1 to 7, characterized in that the at least one connecting portion (144) comprises a recess (150) and / or passage opening (178) which has a main extension direction which is oblique or parallel to a extends to the circumferential direction (138) of the base body (140) tangent.

9. guide element (124) according to one of claims 1 to 8, characterized in that the guide element (124) comprises at least one holding element (164), which is completely or partially disposed on a radially inner side (163) of the guide element (124) and extending from the base body (140) radially in the direction of the ring center axis (142).

10. guide element (124) according to one of claims 1 to 9, characterized in that the base body (140) of the guide element (124) is at least approximately annular portion-shaped and has two open ends (154).

11. Guide element (124) according to claim 10, characterized in that an open end (154) or both open ends (154) have a projection (170) or recess which in mounted

State of the piston (100) engages in particular in a complementary thereto formed recess or projection on a piston skirt (116) of the piston (100) and / or engages.

12. Guide element (124) according to one of claims 1 to 11, characterized in that the guide element (124) comprises or is formed from one or more of the following polymers:

Polyetheretherketone (PEEK), polyamide (PA), polyimide (PI),

Polyoxymethylene (POM), polyphthalamide (PPA), polyester, vinyl ester, hard-tissue polymer, in particular phenol-based, polyester-based and / or vinylester-based, polyphenylene sulfide (PPS) and fluoropolymer, in particular perfluoroalkoxy polymer (PFA), melt-processible Polytetrafluoroethylene (PTFE) polymer and polytetrafluoroethylene (PTFE).

Piston device (102), wherein the piston device (102) comprises:

- A cylindrical piston receptacle (104) for receiving a piston (100); and a piston (100) which is mounted linearly displaceably in the piston receptacle (104),

the piston (100) comprising a piston head (106) for receiving and / or generating pressure forces,

wherein the piston (100) comprises a bolt receptacle (110) for receiving a piston pin (112),

wherein the piston (100) comprises a piston skirt (116) for transmitting power between the piston head (106) and the bolt receptacle (110),

wherein the piston skirt (116) has an at least approximately cylindrical or cylindrical section-shaped lateral surface

(118), in which one or more depressions (120) are arranged, which extend at least approximately annularly or in the form of a ring section about a longitudinal central axis (122) of the lateral surface (118); and

- One or more guide elements (124) for guiding the piston (100) in the piston device (102), in particular according to one of claims 1 to 12, wherein at least one guide element (124) of the one or more guide elements (124) in at least one of the recesses (120) extends.

14. Piston device (102) according to claim 13, characterized in that the one or more recesses (120) each have two flanks (126) which are aligned at least approximately perpendicular to the longitudinal central axis (122) of the lateral surface (118) and to which Edge portions (132), in particular contact surfaces (148), the one or more guide elements (124) abut and / or are held under tension.

15. piston device (102) according to claim 13 or 14, characterized

characterized in that the piston (100) comprises a first metallic material (123) or is formed from a first metallic material (123), wherein the piston receptacle (104) in a Piston receiving body (105) is arranged, which comprises a second metallic material (125) or from a second

metallic material (125) is formed, wherein the first metallic material (123) has a lower thermal expansion coefficient than the second metallic material (125).

A method of making a guide member (124) for a piston (100), such as a guide member (124) according to any one of claims 1 to 12, comprising:

Providing a base body (140) of the guide element (124) which is at least approximately ring-shaped or ring-shaped and which extends in a circumferential direction (138) at least approximately annularly or annularly around a ring central axis (142); and

Providing and / or generating at least one connecting portion (144) for elastically and / or resiliently connecting edge portions (132) of edges (130) of the base body (140) which extend in an axial direction (146) parallel to the ring central axis (142). opposite each other.