US 4,242,946 AGranted

Fluid pressure cylinder convertible for use with or without internal bumpers

AssigneeHumphrey Products Company

InventorVytautas J. Toliusis

Life of this patent

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Abstract

A fluid pressure cylinder which utilizes a standardized housing, piston and piston rod for forming a cylinder assembly either with or without bumpers. The bumpers can optionally be positioned on the piston when desired, with the overall assembled length and maximum stroke of the cylinder being identical whether provided with or without bumpers. The piston is selectively mounted on the piston rod in one axial orientation if bumpers are not used, and the piston is reversed and mounted on the piston rod in the opposite axial orientation when bumpers are used.

Claims26

Dependent claims

In a fluid pressure cylinder having an identical preselected piston stroke whether provided with or without resilient bumpers, said cylinder including a housing having spaced end caps fixedly connected by a sleeve, piston means slidably and sealingly engaged with the interior of said sleeve for reciprocating movement relative to said housing between first and second end postions disposed adjacent said first and second end caps respectively, and a piston rod fixed to said piston means and slidably projecting outwardly through at least one of said end caps, the improvement comprising:

said piston being axially nonsymmetrical and selectively axially oriented in one axial orientation or the other, relative to said housing, so as to be respectively used with or without resilient bumpers;
connecting means for fixedly joining said piston means to said piston rod in either axial orientation of said piston means relative to said housing, said connecting means including first means on said rod engageable with second means on said piston means;
first stop means cooperating between said first end cap and said piston means for defining said first position when said piston means is in said one axial orientation relative to said housing, said first stop means including a first rigid axially-facing stop surface on said first end cap and adapted for engagement with a second axially-facing stop surface on said piston means adjacent one end thereof;
second stop means cooperating between said second end cap and said piston means for defining said second position when said piston means is in said one axial orientation, said second stop means including a third rigid axially-facing stop surface on said second end cap and adapted for engagement with a fourth resilient axially-facing stop surface on said piston means adjacent the other end thereof;
third stop means cooperating between said first end cap and said piston means for defining said first position when said piston means is in said opposite axial orientation relative to said housing, said third stop means including a fifth rigid axially-facing stop surface on said piston means adjacent said other end thereof and adapted for engagement with said first stop surface;
fourth stop means cooperating between said second end cap and said piston means for defining said second position when said piston means is in said opposite axial orientation, said fourth stop means including a sixth rigid axially-facing stop surface on said piston means adjacent said one end thereof and adapted for engagement with said third stop surface;
said piston means being free of resilient bumper means when disposed in said opposite axial orientation;
said piston means including resilient bumper means mounted thereon when said piston means is disposed in said one axial orientation, said bumper means defining thereon said fourth stop surface with the latter being engaged with said third stop surface when the piston means is at one end of its stroke, the fifth stop surface on said piston means being spaced from and maintained out of engagement with said second end cap when the piston means is at said one end of the stroke;
the axial distance between said first stop surface and said third stop surface at its point of engagement with said fourth stop surface, minus the axial distance between said second and fourth stop surfaces, being equal to said preselected stroke of said piston means when the latter is in said one axial orientation;
and
the axial distance between said first stop surface and said third stop surface at its point of engagement with said sixth stop surface, minus the axial distance between said fifth and sixth stop surfaces, also being equal to said preselected stroke of said piston means when the latter is in said opposite axial orientation.

8 more elements

In a fluid pressure cylinder having a housing defined by first and second spaced end caps fixedly connected by a sleeve, piston means slidably supported within said housing for reciprocating movement, and a piston rod fixed to said piston means and slidably projecting outwardly through at least one of said end caps, comprising the improvement wherein:

said housing including a set of rigid axially facing stop surfaces disposed interiorly thereof and positioned for cooperation with said piston means for limiting the reciprocating movement thereof, said set including first and second said stop surfaces formed on said first and second end caps respectively, said first and second stop surfaces being both axially and radially spaced apart;
said piston means being axially nonsymmetrical and including two pairs of oppositely and axially facing abutment surfaces, a first said pair of abutment surfaces being positioned for cooperation with said set of stop surfaces when said piston means is mounted on said rod in one axial orientation relative to said housing to define a maximum piston stroke of preselected length, at least one of the abutment surfaces of said first pair being resilient, and a second said pair of abutment surfaces positioned for cooperation with said set of stop surfaces when said piston means is mounted on said rod in an opposite axial orientation relative to said housing to define a maximum piston stroke of said preselected length, both of the abutment surfaces of said second pair being rigid;
said first pair including a first abutment surface disposed adjacent one end of said piston means and facing axially outwardly thereof, and a second abutment surface disposed adjacent the other end of said piston means and facing axially outwardly thereof, said first and second abutment surfaces being both axially and radially spaced apart;
said second pair including a first rigid abutment surface disposed adjacent said other end of said piston means and facing axially outwardly thereof, and a second rigid abutment surface disposed adjacent said one end of said piston means and facing axially outwardly thereof, said first and second abutment surfaces being both axially and radially spaced apart;
the first abutment surface of said first pair being axially adjacent but spaced radially inwardly from the second abutment surface of said second pair, and the second abutment surface of said first pair being axially adjacent but spaced radially outwardly of the first abutment surface of said second pair;
said piston means including resilient bumper means fixed thereto, said bumper means defining one of the abutment surfaces of said first pair;
and
connecting means for fixedly joining said piston means to said piston rod in either axial orientation of said piston means relative to said housing, said connecting means including first means on said rod engageable with second means on said piston means, said second means including substantially identical connecting portions disposed adjacent the opposite ends of said piston means, said first means being engageable with one of said connecting portions when said piston means is disposed in said one axial orientation relative to said housing, said first means being engageable with the other of said connecting portions when said piston means is disposed in said opposite axial orientation relative to said housing.

5 more elements

said piston being axially nonsymmetrical and selectively axially oriented in one axial orientation or the other, relative to said housing, so as to be respectively used with or without resilient bumpers;
said housing including a set of rigid axially facing stop surfaces disposed interiorly thereof and positioned for cooperation with said piston means for limiting the reciprocating movement thereof, said set including a first said stop surface formed on said first end cap, said set also including second and third said stop surfaces formed on said second end cap and axially facing said first stop surface, said second and third stop surfaces being both axially and radially spaced apart;
said piston means including two pairs of oppositely and axially facing abutment surfaces, a first said pair of abutment surfaces being positioned for cooperation with said first and second stop surfaces when said piston means is mounted on said rod in said one axial orientation relative to said housing to define a maximum piston stroke of preselected length, and a second said pair of abutment surfaces positioned for cooperation with said first and third stop surfaces when said piston means is mounted on said rod and in said opposite axial orientation relative to said housing to define a maximum piston stroke of said preselected length;
said first pair including a first resilient abutment surface disposed adjacent one end of said piston means and facing axially outwardly thereof, and a second resilient abutment surface disposed adjacent the other end of said piston means and facing axially outwardly thereof, said first and second abutment surfaces being axially spaced apart;
said second pair including a first rigid abutment surface disposed adjacent said other end of said piston means and facing axially outwardly thereof, and a second rigid abutment surface disposed adjacent said one end of said piston means and facing axially outwardly thereof, said first and second abutment surfaces being axially spaced apart;
the first abutment surface of said first pair being adjacent but axially spaced from the second abutment surface of said second pair, and the second abutment surface of said first pair being adjacent but axially spaced from the first abutment surface of said second pair;
said piston means including first and second resilient bumpers fixed thereto adjacent the opposite ends thereof, said first and second bumpers having exterior axial surfaces respectively defining the first and second resilient abutment surfaces of said first pair;
said piston means when mounted on said rod in said one axial orientation resulting in said first and second abutment surfaces of said first pair being respectively disposed for engagement with said first stop surface and one of said second and third stop surfaces for limiting the reciprocating movement thereof, said piston means absent said first and second bumpers being mountable on said rod in said opposite axial orientation whereby the first and second abutment surfaces of said second pair are respectively positioned for engaging said first stop surface and the other of said second and third stop surfaces for limiting the reciprocating movement thereof;
and
connecting means for fixedly joining said piston means to said piston rod in either axial orientation of said piston means relative to said housing, said connecting means including first means on said rod engageable with second means on said piston means.

7 more elements

In a fluid pressure cylinder having a housing defined by first and second spaced end caps fixedly connected by a sleeve, piston means slidably supported within said housing for reciprocating movement between said end caps, and a piston rod fixed to said piston means and slidably projecting outwardly through at least one of said end caps, the improvement comprising:

said piston means including a rigid annular piston member which is axially nonsymmetrical and which has elastomeric seal ring means mounted thereon in surrounding relationship therewith for creating a slidable sealed engagement with the interior of said sleeve as the piston means is slidably moved within said housing;
said piston means being selectively axially oriented in one or the other axial orientation relative to said housing so as to be respectively used with or without resilient bumpers while still providing a stroke of the same predetermined magnitude;
connecting means for fixedly joining said piston means to said piston rod in either axial orientation of said piston means relative to said housing;
said piston member having defined therein first and second annular grooves disposed in encircling relationship thereto for permitting a resilient washer-like bumper to be mounted within each groove of said piston member, said first and second grooves being individually disposed adjacent the opposite axial ends of the piston member and being suitably axially spaced apart so that said elastomeric seal ring means is disposed axially therebetween;
said piston means, when disposed in one axial orientation relative to said housing, being provided with bumpers within said grooves defining thereon a first pair of stop surfaces positioned for individually abutting the end caps for limiting the stroke of said piston means to a predetermined magnitude, the first pair of stop surfaces including a first axially outwardly facing surface formed on the exposed side of one bumper and a second axially outwardly facing surface formed on the exposed side of the other bumper;
said piston member, when said piston means is disposed in the opposite axial orientation relative to said housing, defining thereon a second pair of stop surfaces disposed for individually abutting the end caps for defining a stroke of said predetermined magnitude;
said second pair of stop surfaces including third and fourth rigid abutment surfaces defined directly on said piston member, said third and fourth surfaces being axially spaced apart so that said elastomeric seal ring means is axially positioned therebetween, said third surface being positioned axially between said elastomeric seal ring means and one of said bumper-receiving grooves, said fourth surface being spaced axially outwardly of the piston member from the other bumper-receiving groove, and said fourth surface being spaced radially inwardly relative to said third surface.

4 more elements

Dependencies are inferred from the claim text.

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Abstract

said piston being axially nonsymmetrical and selectively axially oriented in one axial orientation or the other, relative to said housing, so as to be respectively used with or without resilient bumpers;
connecting means for fixedly joining said piston means to said piston rod in either axial orientation of said piston means relative to said housing, said connecting means including first means on said rod engageable with second means on said piston means;
first stop means cooperating between said first end cap and said piston means for defining said first position when said piston means is in said one axial orientation relative to said housing, said first stop means including a first rigid axially-facing stop surface on said first end cap and adapted for engagement with a second axially-facing stop surface on said piston means adjacent one end thereof;
second stop means cooperating between said second end cap and said piston means for defining said second position when said piston means is in said one axial orientation, said second stop means including a third rigid axially-facing stop surface on said second end cap and adapted for engagement with a fourth resilient axially-facing stop surface on said piston means adjacent the other end thereof;
third stop means cooperating between said first end cap and said piston means for defining said first position when said piston means is in said opposite axial orientation relative to said housing, said third stop means including a fifth rigid axially-facing stop surface on said piston means adjacent said other end thereof and adapted for engagement with said first stop surface;
fourth stop means cooperating between said second end cap and said piston means for defining said second position when said piston means is in said opposite axial orientation, said fourth stop means including a sixth rigid axially-facing stop surface on said piston means adjacent said one end thereof and adapted for engagement with said third stop surface;
said piston means being free of resilient bumper means when disposed in said opposite axial orientation;
said piston means including resilient bumper means mounted thereon when said piston means is disposed in said one axial orientation, said bumper means defining thereon said fourth stop surface with the latter being engaged with said third stop surface when the piston means is at one end of its stroke, the fifth stop surface on said piston means being spaced from and maintained out of engagement with said second end cap when the piston means is at said one end of the stroke;
the axial distance between said first stop surface and said third stop surface at its point of engagement with said fourth stop surface, minus the axial distance between said second and fourth stop surfaces, being equal to said preselected stroke of said piston means when the latter is in said one axial orientation;
and
the axial distance between said first stop surface and said third stop surface at its point of engagement with said sixth stop surface, minus the axial distance between said fifth and sixth stop surfaces, also being equal to said preselected stroke of said piston means when the latter is in said opposite axial orientation.

8 more elements