# US 6,721,134 B1 · Ramp design for dynamic load > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,721,134 B1 - Document ID: US6721134B1 - Status: Granted - Kind: B1 - Application number: 09/553,074 - Filed: 2000-04-20 - Granted: 2004-04-13 - Earliest claimed: 1999-04-21 - Inventors: Kenneth L. Pottebaum; Markus E. Mangold; Curtis A. Trammell - Web page: https://patentgrep.com/patent/US6721134B1 ## CPC - G11B 21/22: while the head is out of operative position - G11B 5/54: with provision for moving the head into or out of its operative position or across tracks - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A magnetic disc drive includes a base, a disc rotatably attached to said base, and a ramp attached to the base near said disc. The magnetic disc drive also has an actuator assembly pivotably attached to the base. The actuator assembly rotates about an actuator pivot point. The actuator assembly further includes a suspension attached to one end of the actuator assembly, and a transducer attached to the suspension. The actuator assembly moves the transducer between a transducing position and an unload position. The suspension includes a lift tab which contacts the ramp at a contact point as the transducer is moved to the unload position. As the actuator assembly moves the transducer to the unload position, the contact point moves toward the actuator pivot point. This results in a change of the resonant frequency of the actuator assembly. The resonant frequency is lower when the transducer is near the end of the ramp proximate the disc. The ramp can have a straight or a curved lift tab contact path. ## Claims ### Claim 1 A magnetic disc drive comprising: a base; a disc rotatably attached to said base; a curved ramp attached to the base near said disc, the ramp comprising substantially curved contact edge defined by an intersection between two surfaces; and an actuator assembly pivotably attached to said base at an actuator assembly pivot point, the actuator assembly further comprising: a suspension attached to one end of the actuator assembly; and a slider attached to said suspension, the slider being movable between a transducing position and an unload position, the suspension including a lift tab configured to contact the edge of the ramp at a contact point such that the contact point moves towards the actuator pivot point as the slider moves towards the unload position, a distance between a tip of the lift tab and the contact point continually increasing, with the contact point also being nearest to the actuator pivot point when the slider is furthest away from the disc. ### Claim 2 (depends on 1) The magnetic disc drive of claim 1 wherein the ramp is trapezoidally shaped. ### Claim 3 (depends on 1) The magnetic disc drive of claim 1 wherein the natural frequency of the actuator assembly increases as the actuator assembly moves the slider towards the unload position. ### Claim 4 (depends on 1) The magnetic disc drive of claim 1 wherein the natural frequency of the actuator assembly progressively increases as the actuator assembly moves the slider from a transducing position towards a fully unloaded position. ### Claim 5 (depends on 1) The magnetic disc drive of claim 1 wherein the natural frequency of the actuator assembly is lower when the lift tab contacts the ramp near the disc than when the lift tab contacts the ramp farther away from the disc. ### Claim 6 (depends on 1) The magnetic disc drive of claim 1 wherein the natural frequency of the actuator assembly is lower when the lift tab contacts the ramp near the disc than when the lift tab is moved up the ramp. ### Claim 7 (depends on 1) The magnetic disc drive of claim 1 wherein the length of the portion of the actuator assembly positioned between the actuator pivot point and the contact point decreases as the actuator assembly moves the transducer toward the unload position. ### Claim 8 (depends on 1) The magnetic disc drive of claim 1 wherein the length of the portion of the actuator assembly positioned between the actuator pivot point and the contact point decreases as the actuator assembly moves the lift tab up the ramp. ### Claim 9 (depends on 1) The magnetic disc drive of claim 1 in which the base and one of the surfaces of the ramp lie in generally parallel planes. ### Claim 10 (depends on 1) The magnetic disc drive of claim 1 in which the two surfaces of the ramp are generally orthogonal to one another. ### Claim 11 An information handling system comprising: a base; a disc rotatably attached to said base; a curved ramp attached to the base near said disc, the ramp further comprising a lift tab contact edge where a lift tab contacts the ramp, the lift tab contact edge being substantially curved; and an actuator assembly pivotably attached to the base at an actuator assembly pivot point, the actuator assembly further comprising: a suspension including a lift that is attached to one end of the actuator assembly; and a transducer affixed to a slider, the slider attached to said suspension, the actuator assembly moving the transducer between a transducing position and an unload position, wherein a natural frequency of the actuator assembly when the lift tab contacts the ramp at a contact point is optimized to prevent the slider from contacting the disc as the transducer is moved to an unload or load position, wherein the ramp is oriented so that the distance between the contact point and the actuator pivot point shortens as the actuator assembly moves the lift tab up the ramp thereby stiffening the actuator assembly, the contact point being nearest the actuator pivot point when the transducer is furthest away from the disc while the distance between a tip of the lift tab and the contact point continually increases as the lift tab travels up the ramp towards the unload position. ### Claim 12 (depends on 11) The information handling system of claim 11 wherein the natural frequency of the actuator assembly increases as the distance between the contact point and the actuator pivot point shortens. ### Claim 13 (depends on 11) The information handling system of claim 11 wherein the ramp further comprises a lift tab contact edge where the lift tab contacts the ramp, the contact point moving toward the actuator assembly pivot point as the actuator assembly moves the lift tab up the ramp toward the unload position. ### Claim 14 (depends on 11) The information handling system of claim 11 wherein the natural frequency when the lift tab contacts the ramp is optimized to provide increased compliance for the actuator assembly. ### Claim 15 (depends on 11) The information handling system of claim 11 wherein the natural frequency when the lift tab contacts the ramp is optimized to with regard to the natural frequencies associated with another disc drive component. ### Claim 16 (depends on 11) The information handling system of claim 11 wherein at least one contact point is the tip of the ramp. ### Claim 17 (depends on 11) The information handling system of claim 11 wherein the natural frequency of the actuator assembly is optimized with regard to the natural frequencies associated with another disc drive component. ### Claim 18 (depends on 11) The information handling system of claim 11 wherein the natural frequency of the actuator assembly is optimized to prevent the slider from bouncing back and contacting the disc. ### Claim 19 (depends on 11) The information handling system of claim 11 wherein the natural frequency of the actuator assembly is optimized to provide increased compliance for the actuator assembly.