Linear path slide

Information

  • Patent Grant
  • 6769350
  • Patent Number
    6,769,350
  • Date Filed
    Thursday, April 4, 2002
    22 years ago
  • Date Issued
    Tuesday, August 3, 2004
    20 years ago
Abstract
This invention relates to a linear path slide (10) with a slide (26) which is arranged slidingly movable in a housing (12) along a sliding guide (20) and safe against torsion and with a hydraulic driving gear (40) integrated into the slide (26) for a shifting movement of the slide (26), whereby a working piston of the hydraulic driving gear (40) is configured with at least two stages, whereby each stage of the working piston forms a partial hydraulic driving gear (40′, 40″) of the hydraulic driving gear (40) so that higher actuation forces can thus be realized.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a linear path slide with a slide which is arranged slidingly movable in a housing along a sliding guide and safe against torsion and with a hydraulic driving gear integrated into the slide for a shifting movement of the slide.




Linear path slides of the type according to the kind are known. They are used in particular as actuators in different devices for the processing and machining of metallic materials and plastic or plastic composite materials. The functions of these structural components typically include the pressing, forming, stamping, bending, beading, punching, cutting, jointing, jointing pressing as well as the carrying out of feeding functions with special requirements. Particular requirements are made to the properties of linear path slides among which, in particular, a very high energy density, a very high guiding exactitude as well as a very high stiffness against transverse loads and torsion are to be found. Furthermore, linear path slides should be constructed as compact as possible and allow, as standardized basic structural components, a flexible universal range of application. Moreover, properties such as maintenance-freedom during the whole lifetime, a robust construction for the use in polluted environment, the possibility of any fitting position, absolute tightness (for example by overhead mounting) and not least a low-cost production are desirable.




Different configurations of linear path slides are known. Because of the required high energy density, they are preferably hydraulic devices. However, basically the design as a pneumatically driven device is also possible.




From the EP 1 050 685 A2, we know a linear path slide in which a hydraulic driving gear is integrated into the slide for obtaining a compact construction and a reduced volume and thus a reduced weight.




SUMMARY OF THE INVENTION




The aim of this invention is to create a linear path slide of the type according to the kind which can realize high actuation forces by maintaining a compact construction.




According to the invention, this aim is achieved by a linear path slide with the characteristics indicated in claim 1. By the fact that a working piston of the hydraulic driving gear is configured at least with two stages, whereby each stage of the working piston forms a partial hydraulic driving gear of the hydraulic driving gear, it is advantageously reached that an increase of the actuation force of the linear path slide is obtained according to the selected multiple-stage design. The actuation forces applied by the individual partial stages are superimposed and thus result in a higher total actuating force.




Thus, due to such linear path slides, high processing forces are applied by maintaining an exact guiding and a high stiffness against transverse loads, for example for cutting tools.




In a preferred embodiment of the invention, it is provided for that the working piston comprises a guiding element guided slidingly along the housing, guiding element which coaxially encompasses a piston rod fixed with respect to the housing, whereby the guiding element constitutes two inner spaces axially spaced to the piston rod and sealed against each other. Due to such a configuration, it is advantageously reached to use the size available for constituting the partial hydraulic driving gears. In particular, there results then a parallel efficacy of the partial hydraulic driving gears so that the increase of the actuation force of the linear path slide can be obtained in a simple way.




According to a further preferred embodiment, two hydraulic working spaces sealed against each other are respectively configured in each of the inner spaces of the guiding element sealed against each other, whereby these working spaces can be optionally charged with hydraulic oil under pressure. Thus, it is advantageously reached that either the adjusting movement of the linear path slide, or the reset movement of the linear path slide can be hydraulically activated.




Further preferred embodiments of the invention result from the other characteristics indicated in the subclaims.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will be explained in detail below with an embodiment with reference to the corresponding drawing which shows in

FIG. 1

a longitudinal section through a linear path slide.











DETAILED DESCRIPTION OF THE INVENTION





FIG. 1

shows a longitudinal path slide designated as a whole as


10


. The longitudinal path slide


10


comprises a housing


12


which constitutes an inner space


14


. The inner space


14


is configured symetrically to a longitudinal axis


16


. An inner wall


18


of the inner space


14


is provided with a slideway


20


which is preferably produced by a casting method in a known way.




When we consider the housing


12


in cross section, it is formed for example cylindrically, in particular however as a right parallelepiped. Correspondingly, the inner space


14


, considered in cross section, has a round or preferably a rectangular cross-sectional area. An outer face


22


of the housing


12


preferably forms a mounting surface and possesses a groove


24


for receiving a feather key or the like which serves for positioning and for absorbing the shifting forces.




A slide


26


which is guided completely free from backlash in the slideway is placed inside the housing


12


, thus in the inner space


14


. Considered in cross section, the slide


26


possesses a contour which is adapted to the inner space


14


, is thus preferably configured as a right parallelepiped. The slide


26


forms a prismatic slide. The slide


26


possesses a section


28


, protruding lengthwise over the housing


12


, which constitutes an actuation surface


30


. The actuation surface


30


serves for example for receiving tools which are not represented in detail, for example cutting tools or the like, or as a pressure or as a pressing surface which is brought into a bearing contact with a subject to be machined.




The forces which the slide


26


must apply in axial direction and resulting transverse forces are within the range of 10 KN to 150 KN, in individual cases also up to 250 KN. Because of an off-center load of the slide


26


during the working process, in particular for cutting tools placed on the slide


26


, transverse forces which act onto the slide


26


can be a multiple of the nominal longitudinal force.




The housing


12


is closed at its end opposite the section


28


of the slide


26


by a sealing flange


32


. The sealing flange


32


is connected with the housing


12


by intercalating an intermediate plate


34


over connecting means


36


. Thus, the inner space


14


becomes a blind opening so that a motion stopper is constituted for the slide


26


by the sealing flange


32


or the intermediate plate


34


.




The slide


26


forms for its own part a blind opening


38


which is open in direction of the intermediate plate


34


. The blind opening


38


serves for receiving a hydraulic driving gear designated as a whole as


40


. The hydraulic driving gear


40


is thus integrated into the slide


26


.




The blind opening


38


of the slide


26


forms the cylinder of the hydraulic driving gear which receives a working piston. The working piston comprises a piston rod


42


which engages with an ring shoulder


44


into a ring groove


46


constituted correspondingly by the sealing flange


32


and the intermediate plate


34


. The piston rod


42


is thus positioned aligned with the longitudinal axis


16


. The piston rod


42


is thus placed fixed, i.e. not movable lengthwise.




The piston rod


42


is coaxially encompassed by a guiding element


48


which constitutes a first section


50


forming a cylinder tube


50


′ and a second section


52


. The sections


50


and


52


have a circumferential backlash of approximately 0.5 mm to the inner wall


54


of the blind opening


38


of the slide


26


. A guiding without any backlash is also possible. It comes to the formation of an ring space


56


between the guiding element


48


and the piston rod


42


.




The section


50


of the guiding element


48


is closed pressure sealed by a plug


58


at its front side turned to the section


28


of the slide


26


. The plug


58


is screwed into the cylinder tube


50


′, i.e. it is screwed by means of an external thread


60


into an internal thread of the cylinder tube


50


′. A gasket


62


which is outlined here is additionally provided.




The sections


50


and


52


of the guiding element


48


are non-positively connected with each other, for example over a thread connection


64


. For this purpose, the sections


50


and


52


are provided with respective corresponding recesses at their ends which are turned to each other.




The piston rod


42


possesses a first section


66


with a smaller diameter and a second section


68


with a bigger diameter. A transition piece


70


is placed on the section


66


, this transition piece being placed tightly to the piston rod


42


with a gasket


72


and to the guiding element


48


with gaskets


84


. Thus, there comes to the constitution of a first inner space


74


and of a second inner space


76


of the ring space


56


. The transition piece


70


thus forms a bulkhead wall between the inner spaces


74


and


76


. The transition piece


70


engages with a ring shoulder


78


into a corresponding ring recess


80


between the sections


50


and


52


of the guiding element


48


. Thus, the guiding element


48


and the transition piece


70


are placed in such a way that they are not movable in relation to each other.




The piston rod


42


carries a first piston


82


fixedly placed thereon which is placed opposite the plug


58


. The piston


82


is guided by gaskets


84


on the section


50


of the guiding element


48


so that it comes to the constitution of a hydraulic working space


86


between the piston


82


and the plug


58


.




Due to the arrangement of the piston


82


and of the transition piece


70


, the inner space


74


also simultaneously forms a hydraulic working space


75


.




The piston rod


42


carries a second piston


88


which is also fixedly placed on the piston rod


42


. The piston


88


is guided by means of gaskets


90


on the section


52


of the guiding element


48


. Thus, there comes to the constitution of a hydraulic working space


92


between the piston


88


and the transition piece


70


.




Furthermore, the piston rod


42


is encompassed by a screwed connection


94


which is tightly placed on the piston rod


42


by means of gaskets


96


. The screwed connection


94


simultaneously forms a front side seal for the guiding element


48


and the slide


26


. Due to the arrangement of the screwed connection


94


, the inner space


76


simultaneously also forms a hydraulic working space


77


.




The piston rod


42


possesses a first axial bore hole


100


and a second axial bore hole


102


. The axial bore hole


100


runs on the one side into the hydraulic working space


86


and over a radial bore hole


104


into the hydraulic working space


92


. The axial bore hole


102


runs over a radial bore hole


106


into the hydraulic working space


74


and over a radial bore hole


108


into the hydraulic working space


76


. The axial bore holes


100


or


102


are respectively connected with a hydraulic oil connecting flange


110


or


112


. The connecting flanges


110


or


112


are connected with not represented hydraulic oil sources.




The linear path slide


10


represented in

FIG. 1

shows the following functions.




For drawing out the slide


26


, hydraulic oil is set under pressure at the connecting flange


110


. Due to the pressure connection over the axial bore hole


100


, the pressure builds up in the hydraulic working space


86


and over the radial bore hole


104


additionally in the hydraulic working space


92


. Thus, a force of pressure orientated to the left—according to the representation of FIG.


1


—is exerted onto the plug


58


and the transition piece


70


. An actuation force resulting herefrom depends on the pressure head and on the pressure loaded surface. Thus, there results the surface of the plug


58


which is turned to the hydraulic working space


86


as pressure loaded surface and the surface of the transition piece


70


which is turned to the hydraulic working space


92


as pressure loaded surface. These pressure loaded surfaces add up to a whole pressure loaded surface so that, compared with the known linear path slides, a higher actuation force can be applied. However, the surface of the transition piece


70


is not completely integrated into the increase of force but must be reduced by the cross section of the section


66


of the piston rod


42


.




The force which is building up is transferred over the plug


58


and the guiding element


48


to the slide


26


so that the slide is submitted to a corresponding axial adjusting movement along the longitudinal axis


16


. The maximal stroke of the slide


26


is predetermined here by the axial distance of the piston


82


to the transition piece


70


or of the piston


88


to the screwed connection


94


.




A reset movement of the slide


26


is possible in that hydraulic oil under pressure is applied to the connecting flange


112


. This pressure builds up over the axial bore hole


102


and the radial bore holes


106


and


108


in the hydraulic working spaces


75


and


77


. A restoring force orientated to the right—according to the representation in FIG.


1


—builds up according to the pressure loaded surface of the transition piece


70


which is turned to the hydraulic working space


75


and to the pressure loaded surface of the screwed connection


94


which is turned to the hydraulic working space


77


, whereby this restoring force moves the slide


26


into the housing


12


. The screwed connection


94


constitutes simultaneously with the ring shoulder


44


of the piston rod


42


a reset stopper.




It is clear that, due to the arrangement of two pistons


82


or


88


on the piston rod


42


—by intercalating a transition piece


70


—the hydraulic driving gear


40


is configured with two stages so that there results an increase of the pressure loaded surface and thus an increase of the actuation force. The piston


82


constitutes in connection with the hydraulic working space


86


and with the section


50


of the guiding element


48


a first partial hydraulic driving gear


40


′, while the piston


88


in connection with the transition piece


70


and the guiding element


48


constitutes a second partial hydraulic driving gear


40


″.




With respect to the further advantages of the linear path slide


10


, in particular with respect to its compact construction and to the fundamental advantages of a hydraulic driving gear


40


integrated into the housing


12


, we refer to the EP 1 050 685 A2, the content of which is made herewith to the content of disclosure of this invention.




The invention self-evidently is not limited to the represented embodiment. So, multiple stage constructions (with more than two stages) are also conceivable. It comes then either to a reduction of the maximal stroke of the linear path slide, or to a bigger axial extension of the linear path slide.















List of reference numerals


























 10




Linear path slide







 12




Housing







 14




Inner space







 16




Longitudinal axis







 18




Inner wall







 20




Slideway







 22




Outer face







 24




Groove







 26




Slide







 28




Section







 30




Actuation surface







 32




Sealing flange







 34




Intermediate plate







 36




Connecting means







 38




Blind opening







 40




Hydraulic driving gear







 40′




First partial hydraulic driving gear







 40″




Second partial hydraulic driving gear







 42




Piston rod







 44




Ring shoulder







 46




Ring groove







 48




Guiding element







 50




First section







 52




Second section







 54




Inner wall







 56




Ring space







 58




Plug







 60




External thread







 62




Gasket







 64




Threaded connection







 66




First section







 68




Second section







 70




Transition piece







 72




Gasket







 74




First inner space







 75




Hydraulic working space







 76




Second inner space







 77




Hydraulic working space







 78




Ring shoulder







 80




Ring recess







 82




Piston







 84




Gaskets







 86




Hydraulic working space







 88




Piston







 90




Gaskets







 92




Hydraulic working space







 94




Screwed connection







 96




Gaskets







100




First axial bore hole







102




Second axial bore hole







104




Radial bore hole







106




Radial bore hole







108




Radial bore hole







110




Connecting flange







112




Connecting flange














Claims
  • 1. A linear path slide, comprising: a housing; a sliding guide arranged in the housing; a slide arranged to beslidingly movable in the housing along the sliding guide and prevented from rotation; and a hydraulic driving gear integrated into the slide for a shifting movement of the slide, the hydraulic driving gear having a working piston configured with two stages, whereby each stage of the working piston forms a partial hydraulic driving gear of the hydraulic driving gear, the working piston including a piston rod fixed with respect to the housing and a guiding element guided slidingly along the housing, the guiding element coaxially encompassing the piston rod, the guiding element forms two inner spaces axially spaced to the piston rod and sealed against each other, the guiding element is closed and pressure sealed at one end by a plug and at another end by a screwed connection, and has a transition piece that forms the inner spaces, the guiding element has two sections between which the transition piece is held, the piston rod has a first, smaller diameter section and a second, larger diameter section, the transition piece being arranged in the first section, the transition piece being placed tightly to the piston rod and the guiding element by gaskets so as to form a first of the inner spaces and a second of the inner spaces, the sections of the guiding element each have a circumferential backlash to an inner wall of a blind opening in the slide, the guiding element being positioned together with the plug, the transition piece and the screwed connection to be movable lengthwise with respect to the piston rod, the piston rod carries a first piston placed in a first of the inner spaces and a second piston placed in a second of the inner spaces so as to divide the inner spaces into hydraulic working spaces.
  • 2. A linear path slide according to claim 1, wherein the sections have a circumferential backlash of 0.5 mm.
  • 3. A linear path slide according to claim 1, wherein the piston rod has a first axial bore hole that is connected with a first hydraulic connecting flange and runs into the hydraulic working spaces.
  • 4. A linear path slide according to claim 3, wherein the piston rod has a second axial bore hole that is connected with a second hydraulic connecting flange and runs into the hydraulic working spaces.
Priority Claims (1)
Number Date Country Kind
201 06 043 U Apr 2001 DE
US Referenced Citations (6)
Number Name Date Kind
2851994 Fagge Sep 1958 A
2982257 Fagge May 1961 A
3457840 Grimes Jul 1969 A
3485141 Ott et al. Dec 1969 A
4137828 Senn Feb 1979 A
6244560 Johnson Jun 2001 B1
Foreign Referenced Citations (1)
Number Date Country
9315211 Dec 1993 DE