Drive line damper

Claim 2

A damping apparatus interconnecting a drive member and a driven member for rotational movement, said apparatus comprising: a housing connected to said drive member for rotation therewith; at lEast two damping cylinders within the housing being hydraulically interconnected by a fluid passageway system, said passageway system permitting hydraulic fluid to flow from one damping cylinder to the other; a force transmitting member connected to said driven member for rotation therewith and having at least one radial lever extension; a piston slidably positioned within each of said damping cylinders and biased so as to bear against opposed sides of said radial extension; and valve means within said housing controlling the flow of hydraulic fluid through said fluid passageway, said valve means including means normally biasing said valve means open to permit a controlled fluid flow through said passageway at rotational speeds less than a predetermined speed, the opening of said valve means being directly proportional to the rotational speed of said drive member, to (1) close said fluid passage at rotational speeds greater than said predetermined speed to positively rotationally interlock said drive and driven members, (2) open said fluid passage, proportional to the speed of said drive member, permitting relative rotational displacement of said drive and driven members and (3) prevent transmission of intermittent and vibrational forces at relatively low rotational speeds.

Claim 3

The apparatus defined in claim 1 characterized in that said force transmitting member is positioned within a central fluid reservoir, said reservoir communicating with and forming a portion of said fluid passageway system.

Claim 4

The apparatus defined in claim 2, further including two lateral bores, and a piston in each bore comprising two spaced, axially aligned piston members adapted to move in unison within said bores, defining four damping cylinders hydraulically interconnected by said fluid passageway system.

Claim 5

The apparatus defined in claim 3, characterized in that said force transmitting member includes at least two radial lever extensions, each extension biased by a pair of said opposed spaced, axially aligned piston members.

Claim 6

The apparatus defined in claim 3, including a compression spring located within each damping cylinder, said springs resiliently biasing its associated piston member in a direction toward said side of said radial extension against which said piston bears, whereby said force transmitting member is resiliently biased by said compression springs for damping low frequency oscillations.

Claim 7

The apparatus defined by claim 4, wherein said passageway system further includes a first passageway interconnecting a cylinder of one lateral bore with a corresponding cylinder of the other lateral bore, and a second passageway interconnecting the other of the two cylinders, relative rotation of said force transmitting member pumping hydraulic fluid out of two of the interconnected damping cylinders, through the fluid passageway system and into the other of the two interconnected damping cylinders.

Claim 8

The apparatus defined by claim 6 characterized in that said housing has two radial bores extending outwardly from said central fluid reservoir, one of said passageways directly connected to one of said radial bores, and the other of said passageways connected directly to the other of said radial bores, whereby the central fluid reservoir region hydraulically connects with each pair of interconnected damping cylinders via one of said radial bores and its associated passageway.

Claim 9

The apparatus defined by claim 7, characterized in that said valve means includes a valve restrictor member slidably positioned within each of said radial bores closing said hydraulic passageway system at rotational speeds greater than said predetermined speed.

Claim 10

A damping apparatus interconnecting a drive member and a driven member of a drive line to eliminate vibrational forces occurring at no load operating conditions, comprising: a housing connected to said drive member for rotation therewith a force transmitting member positioned within said housing for relative rotational movement with respect thereto and connected to said driven member for rotation therewith, said force transmitting member having oppositely directed radial lever extensions; two sets of opposed, cup-shaped pistons bearing against opposed sides of said radial extensions to resiliently bias said force transmitting member, said sets of pistons slidably positioned within parallel lateral bores to define two sets of hydraulic damping cylinders; a central reservoir region, in which said force transmitting member is located, having opposed, radially extending bores defining outer valve chambers; a first hydraulic passageway interconnecting a hydraulic damping cylinder of one such set, a diametrically opposed hydraulic cylinder of the other such set, and one of the outer valve chambers; a second hydraulic passageway interconnecting the other of the two diametrically opposed damping cylinders and the other of the outer valve chambers, whereby a hydraulic passageway system is formed having a central reservoir region and two hydraulic branches each formed by a radially extending bore, a hydraulic passageway and two hydraulic damping cylinders; and centrifugally operated valve means positioned in each radial bore adapted to be normally biased open and to be selectively closed at a predetermined rotational speed of the damper housing, said valve means (1) permitting fluid flow within said hydraulic passageway system at low rotational speeds and (2) preventing fluid flow within said hydraulic passageway system at rotational speeds greater than said predetermined speed to positively rotationally interlock said drive and driven members.

Claim 11

A damping apparatus interconnecting a drive member and a driven member of a drive line to eliminate vibrational forces occurring at no load operating conditions, comprising: a housing connected to said drive member for rotation therewith a force transmitting member positioned within said housing for relative rotational movement with respect thereto and connected to said driven member for rotation therewith, said force transmitting member having oppositely directed radial lever extensions; two sets of opposed, cup-shaped pistons bearing against opposed sides of said radial extensions to resiliently bias said force transmitting member, said sets of pistons slidably positioned within parallel lateral bores to define two sets of hydraulic damping cylinders; a central reservoir region, in which said force transmitting member is located, having opposed, radially extending bores defining outer valve chambers; a first hydraulic passageway interconnecting a hydraulic damping cylinder of one such set, a diametrically opposed hydraulic cylinder of the other such set, and one of the outer valve chambers; a second hydraulic passageway interconnecting the other of the two diametrically opposed damping cylinders and the other of the outer valve chambers, whereby a hydraulic passageway system is formed having a central reservoir region and two hydraulic branches each formed by a radially extending bore, a hydraulic passageway and two hydraulic damping cylinders; and centrifugally operated valve means positioned in each radial bore adapted to be normally biased open and to be selectively closed at a predetermined rotational speed of the damper housing, said valve means (1) permitting fluid flow within said hydraulic passageway system at low rotational speeds and (2) preventing fluid flow within said hydraulic passageway system at rotational speeds greater than said predetermined speed to positively rotationally interlock said drive and driven members.

Claim 12

A damping apparatus interconnecting a drive member and a driven member of a drive line to eliminate transmission of vibrational forces, comprising: a housing connected to said drive member for rotation therewith; a force transmitting member positioned within said housing for relative rotational movement with respect thereto and connected to said driven member for rotation therewith, said force transmitting member having at least one radial lever extension; a set of opposed, cup-shaped pistons bearing against opposed sides of said radial extension to resiliently bias said force transmitting member, said set of pistons slidably positioned within a bore to define a set of hydraulic damping cylinders; a hydraulic passageway system interconnecting said set of damping cylinders to permit fluid flow therebetween in response to movement of said pistons by rotational movement of said force transmitting member relative to said housing; and centrifugally operated valve means within said hydraulic passageway system adapted to be normally biased open and to be selectively closed at a predetermined rotational speed of the damper housing, said valve means permitting fluid circulation through the hydraulic passageway system at low rotational speeds to allow relative rotational movement between said force transmitting member and said housing, and preventing fluid circulation at high rotational speeds to rotationally lock the force transmitting member to the housing.

Claim 13

A damping apparatus interconnecting a drive member and a driven member of a drive line to eliminate transmission of vibrational forces, comprising: a housing connected to said drive member for rotation therewith; a force transmitting member positioned within said housing for relative rotational movement with respect thereto and connected to said driven member for rotation therewith, said force transmitting member having at least one radial lever extension; a set of opposed, cup-shaped pistons bearing against opposed sides of said radial extension to resiliently bias said force transmitting member, said set of pistons slidably positioned within a bore to define a set of hydraulic damping cylinders; a hydraulic passageway system interconnecting said set of damping cylinders to permit fluid flow therebetween in response to movement of said pistons by rotational movement of said force transmitting member relative to said housing; and centrifugally operated valve means within said hydraulic passageway system adapted to be normally biased open and to be selectively closed at a predetermined rotational speed of the damper housing, said valve means permitting fluid circulation through the hydraulic passageway system at low rotational speeds to allow relative rotational movement between said force transmitting member and said housing, and preventing fluid circulation at high rotational speeds to rotationally lock the force transmitting member to the housing.

Claim 14

The apparatus defined in claim 10, characterized in that said force transmitting member includes two oppositely directed radial lever extensions, each such extension being resiliently biased by a set of said opposed, cup-shaped pistons.

Claim 15

The apparatus defined in claim 11 characterized in that said sets of pistons are, respectively, slidably positioned within a set of lateral bores, defining two sets of hydraulic damping cylinders.

Claim 16

The apparatus defined in claim 10 characterized in that said hydraulic passageway system includes a central reservoir region in which said force transmitting member is located.

Claim 17

The apparatus defined in claim 13 characterized in that said hydraulic passageway system further includes a bore extending radially outwardly from said central reservoir region, said centrifugally operAted valve means being positioned within said radial bore.

Claim 18

The apparatus defined in claim 14 characterized in that said centrifugally operated valve means includes a radially oriented piston (1) biased radially outwardly by centrifugal force developed by rotation of said damper housing and (2) closing said hydraulic passageway system at said predetermined rotational speed due to radial movement effected by centrifugal force.

Claim 19

The apparatus defined in claim 15 characterized in that said hydraulic passageway system further includes two opposed radial bores housing similar centrifugally operated valve means and radially oriented pistons, said radially oriented pistons having equal masses to simultaneously effect closure of said hydraulic passageway system.