CN110005657A - Hydraulic cylinder - Google Patents

Abstract

A kind of hydraulic cylinder with cylinder housing is disclosed, a kind of piston with piston rod is slidingly guided in the cylinder housing.The piston rod is guided out from cylinder housing by shell nozzle.Sealing element is provided in shell nozzle, the sealing element is around piston rod.The sealing element has at least one head tank on the side of the outer surface of the sealing element, the head tank is fluidly connected with region between the sealing element and the piston rod, wherein the region is seen in a longitudinal direction in the height that the head tank is arranged in.Alternatively or additionally, the piston can have piston seal, and the piston seal surrounds the piston.The piston seal can have a head tank at the inner surface of the piston seal, the head tank so see in a longitudinal direction head tank height upper fluid be connected with the region between piston seal and cylinder housing.

Description

Hydraulic cylinder

Technical field

The present invention relates to a kind of hydraulic cylinders as described in the preamble according to claim 1.

Background technique

It is known from the state of the art hydraulic cylinder perhaps waterpower cylinder (Hydrozylinder) hydraulic cylinder or waterpower cylinder tool There is cylinder sleeve, which has head and bottom.Slidingly guide piston in the cylinder sleeve, the piston by first pressure room with Second pressure room separates.At least one piston rod extends since piston, and the piston rod runs through the head, and to overhanging Out.

The hydraulic cylinder as known to DE 10 2,013 212 224 is provided with gap in the hydraulic cylinder in the region on head Set, the gap set is around piston rod.The gap set together forms gap sealing part with piston rod.The gap covers This gap set outer surface locally using pressure medium by being loaded radially inward by adjacent pressure chamber.It is described The inner surface of gap set is equally loaded by pressure medium, wherein the pressure acted on the internal surface is seen simultaneously in a longitudinal direction And it sees along direction from inside to outside and linearly reduces.The gap set is adversely related to the manufacture of accurate and expense highland Metalwork.The metalwork is extremely sensitive relative to pressure distortion.

It is alternatively covered in gap it is contemplated that a kind of elastomeric seal is arranged, but wherein piston rod adversely exists It rubs on the elastomeric seal.In addition, the elastomeric seal has relatively high abrasion.

Summary of the invention

In contrast, the present invention is based on following tasks: completing a kind of hydraulic cylinder, the hydraulic cylinder is that expense is advantageous And there is smaller friction not rub perhaps and have smaller abrasion or do not wear.

The task is resolved according to the features of claim 1.

Of the invention is advantageously improved the theme that scheme is dependent claims.

A kind of cylinder, particularly a kind of hydraulic cylinder with cylinder housing arranged according to the present invention.Piston rod is herein from cylinder shell Body is guided by shell nozzle.The annular in shell nozzle is preferably provided between the piston rod and cylinder housing Sealing element.The sealing element can surround the piston rod.It additionally can be set, the piston rod is from cylinder shell The piston being guided in body extends away from, and the piston can be surrounded by a kind of piston seal of annular, the piston Sealing element is for example arranged on piston.It has been advantageously provided at least one head tank (Drucktasche).The head tank can be with Furthermore it is limited by the outer surface of the sealing element around piston rod.Head tank can be sealed by fluid path with a kind of Sealing area defined by the inner surface of element is connected.In addition, the head tank can for example be sealed.From the head tank From the point of view of setting out, the sealing area is located at the radial inside of the head tank.The sealing area and the head tank can be with Therefore it for example sees along radial direction and is successively arranged in rows.The sealing area is preferably by sealing element and piston rod institute It limits.It alternatively or additionally can be set, construct a kind of head tank, the head tank is by the piston seal around piston The inner surface of part is limited.The head tank can so be further advanced by fluid path and the outer surface by piston seal Defined by sealing area be connected.The sealing area is so preferably arranged in the diameter of head tank from the point of view of head tank To outside, wherein the head tank and sealing area are seen along radial direction and can be arranged in rows.The sealing area is excellent Selection of land is limited by the sealing element and by the cylinder housing.

The solution has the advantages that the sealing element and/or piston seal are in the area of their head tank Basic upper pressure balance in domain.According to the quantity of the construction of head tank and head tank, piston seal can also be for example carried out And/or the discharge degree substantially completely of sealing element.If between the sealing element and the piston rod or in piston seal Gap sealing part is provided between part and cylinder housing, then the gap sealing part can pass through at least one head tank Or the corresponding structural scheme of at least one each head tank constructs.It can therefore advantageously by the head tank Such as small gap is constructed with determining leakage, wherein it is not necessary that, accurately and expense highland manufacture it is described close Seal element and/or piston seal.In fact, sealing element inside diametrically and/or outside piston seal diametrically It can compare and inaccurately, be for example made of advantageous plastics, without thus negatively affecting the gap sealing.The seam As gap sealing can cross as already explained above, just since at least one described head tank is definitely adjusted.

Head tank discussed below can be related to head tank for sealing shroud and/or for piston seal.Such as Fruit explains a head tank, then the explanation is also applied for multiple or all head tanks.

The head tank preferably along seen on two longitudinal directions of hydraulic cylinder be sealing.It therefore can be by the pressure Power slot is definitely limited in a longitudinal direction.The sealing is preferably realized by additional sealing element.For close Envelope element head tank be so arranged in the outer surface of sealing element, the inner surface of cylinder housing or cylinder housing head interior table Between face and additional sealing element.

In other structural scheme of the invention, the head tank or each head tank can be constructed circlewise, and And around the sealing element and/or the piston seal.Along sealing shroud and/or piston seal longitudinal direction From the point of view of, the head tank can be limited by two sealing elements in the form of sealing ring.In sealing element, sealing ring can To surround the sealing element at periphery.It can be set in piston seal, the sealing ring setting is close in the piston The radial inside of sealing.

It can be set in other structural scheme of the invention, the head tank passes through a kind of construction in sealing element Fluid channel in sealing element is connected with pressure span, this is extremely simple on equipment and technology.Alternatively or It additionally can be set, fluid channel and pressure of the head tank by construction in piston seal in piston seal Region is connected.Furthermore simply it is contemplated that the fluid channel is configured to radial hole or diameter on equipment and technology To channel, the fluid channel can be simply manufactured.Furthermore it is contemplated that multiple fluid channels are arranged for head tank Or fluid path, so as to the pressure in head tank and between the pressure in pressure span be provided with extremely fast pressure Balance.The multiple fluid path is preferably provided on part circle (Teilkreis), that is to say, that in circumferential direction uniformly Ground is distributed and may construct in the same manner, and which results in sealing element and/or piston seal uniform on head tank Pressure-loaded.The fluid path for example constructs pore-forming star (Bohrungsstern).

In a kind of preferred structural scheme of the invention, multiple head tanks can be set in sealing element.Alternatively Or multiple head tanks can be additionally set in piston seal.It is possible thereby to construct different pressure water in head tank It is flat, to adjust one or the sealing off gap such as more accurately.Preferably, multiple head tanks in a longitudinal direction on It sees and is arranged in rows.This advantageously leads to, such as can be in pressure span between the sealing element and the piston rod in pressure Linear pressure decline is substantially formed on slot.Same situation is suitable for the pressure area between piston seal and cylinder housing Domain.Therefore can be balanced by one or more pressure chamber opposite with pressure span in sealing off gap along vertical The linear or non-constant pressure history seen from inside to outside to direction.Such as can make sealing element and/or Piston seal, due to the linear pressure history in sealing off gap and come expansion pass through in head tank or chamber In the pressure history of classification balanced, the head tank or chamber resist the expansion.It is contemplated that A kind of especially sealing element common, especially in the form of sealing ring is set between two head tanks, this is in equipment skill It is extremely simple in art.

Preferred mode, the sealing element has a kind of special for the sealing ring or for each sealing ring It is the annular recess for drawing system from outer surface, the sealing ring can be definitely fixed simply on equipment and technology with this.It is standby The piston seal perhaps additionally can be set in selection of land has for the sealing ring or for each sealing ring A kind of annular recess for especially drawing system from inner surface.Sealing element with the sealing ring and/or there is the sealing The piston seal of ring can so form a kind of unit, and the unit can be installed simply.

Preferred mode, the sealing element in cylinder housing is loaded into open annular groove radially inward.It can With consideration, the annular groove is set in the cylinder head of hydraulic cylinder or guide sleeves.The sealing element so can be radial Ground is upcountry stretched out from open annular groove.It alternatively or additionally can be set, the piston seal in piston It is loaded into a kind of annular groove open radially outward, and is radially outwardly stretched out from the annular groove.Pass through institute Annular groove is stated the sealing element and/or piston seal are definitely fixed in hydraulic cylinder or are fixed in piston.

The sealing element and/or the piston seal are for example related to a kind of gap set.The sealing element and/or institute It states piston seal and is preferably particularly for example configured to hollow cylinder.

Detailed description of the invention

A preferred embodiment of the present invention is further illustrated below by schematical attached drawing.Attached drawing is shown :

A kind of office in the region of the exit opening of the hydraulic cylinder of hydraulic cylinder according to embodiment of the Fig. 1 in sectional side elevation Portion's figure；

The Local map in the region of the piston of the hydraulic cylinder of hydraulic cylinder according to another embodiment of the Fig. 2 in sectional side elevation； With

A part of sealing element of the Fig. 3 in sectional side elevation.

Reference signs list:

1 hydraulic cylinder；

2 piston rods；

4 exit openings；

6 cylinder housings；

8 annular grooves；

10；54 gaps set；

12,14,16,18；42,44,46,48；56 head tanks；

20,50 sealing rings；

22 fluid channels；

24；52 pressure spans；

The decline of 26 pressure；

28 end sections；

30 pistons；

31 cylinder sleeves；

32,34 pressure chambers；

36 outer surfaces；

38 annular grooves；

40 piston seals；

58 gaps.

Specific embodiment

A kind of hydraulic cylinder 1 is shown according to Fig. 1, the hydraulic cylinder is schematically shown in dotted line.The hydraulic cylinder, which has, lives Stopper rod 2, the piston rod are stretched out by exit opening 4 from cylinder housing 6.The quilt in the surface around the piston rod 2 of annular groove 8 System is drawn into the cylinder housing.It has been put into the annular groove with the sealing element of the form of gap set 10.The gap covers Annular, and around the piston rod 2.Gap set 10 with the outer surface 4 of gap set define head tank 12, 14,16 and 18.The head tank is so respectively configured between the slot bottom of annular groove 8 and the outer wall surface of gap set 10.Pressure Slot 12 to 18 is disconnected from each other by sealing ring 20, and for simplicity, the only one sealing ring in the sealing ring is equipped with attached Icon note.The head tank 12 and 18 of each side is so defined towards side by sealing ring 20.Sealing ring 20 is around institute Gap set 10 is stated, and is respectively put into the annular groove of outside of the gap set 10.In addition, from each head tank 12 to 18 There is fluid channel 22 radially inwardly to extend respectively, for simplicity, only one fluid channel in the fluid channel Equipped with appended drawing reference.By each fluid channel 22, each head tank 12 to 18 is so with pressure span 24 in piston rod 2 Section between gap set 10 is fluidly connected.If existed now inside (p_1) from outer (p_2) in pressure span 24 The linear pressure decline being marked by arrow 26, then the head tank 12 to 18 be respectively provided with it is mutually different Pressure, wherein head tank 12 have highest pressure, and the pressure in head tank 14 to 18 then and it is respective along Slot on longitudinal direction in terms of the interior of the slave cylinder housing 6 of piston rod 2 in front, which is compared, becomes smaller respectively.Therefore, It is seen in a longitudinal direction and produces the pressure history of substantial linear by multiple head tanks 12 to 18.It is described along longitudinal direction Side's inner most sealing ring 20 that looks up is separated the one of gap set 10 in the outer surface section of end side with head tank 12 ?.The outer surface section is fluidly connected with the entrance area before the pressure span 24 is arranged in, and therefore has Compared to the adjacent higher pressure of head tank 12.It is described to define head tank 18, last sealing ring 20 by the gap One outer surface section of set 10 is separated with head tank 18.The outer surface section is so fluidly connected with the exit region in region 24 It connects, and is therefore loaded with the smallest pressure.

Piston 30 is shown according to fig. 2, and piston (see figure 1) in the cylinder sleeve 32 of hydraulic cylinder 1 is guided.The piston First pressure room 32 and second pressure room 34 are separated.Annular groove 38 draws system into the outer surface of piston 30 36.The piston of annular Sealing element 40 is encased in the annular groove, and the piston seal is around piston 30.The piston seal 40 can be configured to Gap set.The piston seal 40 defines multiple head tanks 42 to 48 using the inner surface of the piston seal, described more A head tank is arranged in rows along the longitudinal direction of piston 30, and around piston 30.Head tank 42 to 48 is mutual respectively It is limited by sealing ring 50, wherein for simplicity only one sealing ring is equipped with appended drawing reference in Fig. 2.The sealing ring 50 can be loaded into respectively in the annular groove of each inside of piston seal 40 herein.Distinguish from each head tank 42 to 48 There is fluid channel 22 to extend along radial direction, wherein for simplicity only one fluid channel is equipped with appended drawing reference.Stream Body channel 22 is connected with the section of the pressure span 52 between the outer surface of piston seal 40 and cylinder sleeve 32.

According to the operating status in Fig. 2, there is than pressure (p_1) higher in pressure chamber 32 in pressure chamber 34. Therefore it looks from pressure chamber 34s along the longitudinal direction of piston 30 towards pressure chamber 32 in pressure span 52 and has occurred one The pressure that kind linearly declines.Therefore head tank 42 to 48 forms a kind of substantial linear corresponding to embodiment in Fig. 1 Pressure history.In addition, piston seal 40 has an inner surface section, the inner surface portion on the side of pressure chamber 34 Section is limited by the sealing ring 50 of edge side, and is fluidly connected with pressure chamber 34.The piston seal 40 is in the work There is an inner surface section, the inner surface section quilt at end section on the side that pressure chamber 32 is set of plug seal External sealing ring 50 is limited, and is fluidly connected with pressure chamber 32.

Another embodiment of gap set 54 is shown in FIG. 3.The embodiment and Fig. 1 differently only have one Head tank 56.The head tank in a longitudinal direction on see construction between two sealing rings 20.The sealing ring 20 on right side in Fig. 3 Furthermore by gap 58 its from head tank 56 far from be directed toward side on can load highest pressure.

A kind of hydraulic cylinder with cylinder housing is disclosed, the piston with piston rod is slidably drawn in the cylinder housing It leads.The piston rod is guided out by shell nozzle from cylinder housing.Sealing element is provided in shell nozzle, it is described close Element is sealed around the piston rod.The sealing element has at least one pressure on the side of the outer surface of the sealing element Power slot, the head tank are fluidly connected with region between the sealing element and the piston rod, wherein the region is along vertical It is seen in the height that head tank is set to direction.Alternatively or additionally, the piston can have piston seal, described Piston seal is around piston.The piston seal can have head tank, institute on the inner surface of the piston seal Head tank is stated so fluidly to see in a longitudinal direction in the height of head tank and between piston seal and cylinder housing Region is connected.

Claims (11)

1. the hydraulic cylinder with cylinder housing (6) and piston rod (2), the piston rod pass through shell nozzle from the cylinder housing (6) (4) it is guided, wherein in the sealing element for being provided with annular in the shell nozzle between piston rod (2) and cylinder housing (6) (10), around the piston rod (2), and/or wherein, the piston rod (2) is guided the sealing element from cylinder housing Piston (30) extend away from, the piston is surrounded by the piston seal (40) of annular, which is characterized in that provided with extremely A few head tank (12,14,16,18), at least one described head tank are limited by the outer surface of sealing element (10), and At least one described head tank is connected by fluid path with the pressure span defined by the inner surface of the sealing element, Wherein the pressure span starts to look positioned at the radial inside of the head tank from head tank (12,14,16,18), and/or At least one head tank (42,44,46,48) is set, at least one described head tank is by the inner surface institute of piston seal (40) It limits, and at least one described head tank is by fluid path (22) and defined by the outer surface of piston seal (40) Region (52) is connected, wherein region (52) from head tank (42,44,46,48) set out from the point of view of positioned at the head tank radial direction Outside.

2. hydraulic cylinder according to claim 1, wherein the head tank (12,14,16,18；42,44,46,48；56) edge Two longitudinal directions of piston rod (2) see and sealed.

3. hydraulic cylinder according to claim 1 or 2, wherein the head tank (12,14,16,18；42,44,46,48；56) It circlewise constructs, and around the sealing shroud (10) and/or the piston seal (40).

4. hydraulic cylinder according to any one of the preceding claims, wherein the head tank (12,14,16,18；42,44, 46,48；56) it sees along sealing shroud (10) and/or piston seal (40) longitudinal direction by two sealing rings (20；50) institute It limits.

5. hydraulic cylinder according to any one of the preceding claims, wherein the head tank (12,14,16,18) is sealing It is connected by a kind of fluid channel (22) of construction in sealing element (10) with pressure span (24) in the case where element (10) It connects, and/or wherein the head tank (42,44,46,48) is constructed by a kind of in piston in the case where piston seal (40) Fluid channel (22) in sealing element (40) is connected with pressure span (52).

6. hydraulic cylinder according to any one of the preceding claims, wherein being provided in the case where sealing element (10) more A head tank (12,14,16,18), and/or wherein in the case where piston seal (40) be provided with multiple head tanks (42, 44,46,48), the pressure span (24 that the multiple head tank passes through pressure-path (22) respectively and is configured；52) it is connected.

7. hydraulic cylinder according to claim 6, plurality of head tank (12,14,16,18；42,44,46,48) in rows Arrangement.

8. hydraulic cylinder according to claim 6 or 7, wherein respectively in two head tanks (12,14,16,18；42,44,46, 48) sealing ring (20 is set between；50).

9. hydraulic cylinder according to claim 8, wherein the sealing element (10) is for the sealing ring or for each A sealing ring (20) have annular recess, and/or wherein the piston seal (40) for the sealing ring or for each A sealing ring (50) has annular recess.

10. hydraulic cylinder according to any one of the preceding claims, wherein sealing element (10) quilt in cylinder housing (6) It is encased in open annular groove (8) radially inward, and is stretched out radially inward from the annular groove, and/or wherein in work Piston seal (40) in plug (30) is loaded into open annular groove (38) radially outward, and from the annular groove diameter It is protruding to ground.

11. hydraulic cylinder according to any one of the preceding claims, wherein the sealing element and/or the piston seal Part is configured to gap set.