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US5791231A Expired / Lapsed US ⏱️ 0.0 years remaining

Surgical robotic system and hydraulic actuator therefor

Assignee: Endorobotics Corp
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Filing: 1993-05-17
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Granted: 1998-08-11
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Expires: 2013-05-17
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Abstract

Abstract A hydraulic actuator is described which has a layered structure and a flattened piston assembly to enhance production speed and reduce the costs of assembly. A system for performing surgery is also described incorporating the hydraulic actuator, having a sensory glove, a computer, and a slender robot manipulator which can be inserted into the human body through a small incision. The robot manipulator has a layered structure with integrated hydraulic pistons. This design allows the use of a novel manufacturing process in which all of the parts are formed from laminated sheets of material. Seals are formed to prevent leakage of hydraulic fluid by introducing castable rubber into enclosed channels in the structure.

Inventors

  • 👤 Michael B. Cohn
  • 👤 D. Curtis Deno
  • 👤 Jennifer T. Fujii

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 14:30
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/10; B25J9/14; B25J9/144; A; A61; A61B; A61B34/00; A61B34/30; B25J15/00; B25J15/02; B25J15/0206; A61B17/00; A61B2017/00535; A61B2017/00539; A61B34/70; A61B34/74; A61B2034/741

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 117 words
A layered hydraulic actuator comprising a top plate, a middle plate, a bottom plate, a piston, and means for conducting hydraulic fluid; wherein the middle plate comprises at least one chamber adapted to receive the piston and permit the piston to move up and down the length of the chamber; wherein the means for conducting hydraulic fluid empties into the chamber housing the piston such that the piston is displaced up and down the length of the chamber when the hydraulic fluid flows into and out of the chamber; and wherein the top plate and the bottom plate are attached to the top and bottom, respectively, of the middle plate, thereby enclosing the chamber containing the piston.
Claim 2
Dependent Claim 117 words
A layered hydraulic actuator comprising a top plate, a middle plate, a bottom plate, a piston, and means for conducting hydraulic fluid; wherein the middle plate comprises at least one chamber adapted to receive the piston and permit the piston to move up and down the length of the chamber; wherein the means for conducting hydraulic fluid empties into the chamber housing the piston such that the piston is displaced up and down the length of the chamber when the hydraulic fluid flows into and out of the chamber; and wherein the top plate and the bottom plate are attached to the top and bottom, respectively, of the middle plate, thereby enclosing the chamber containing the piston.
Claim 3
Dependent Claim 19 words
An actuator according to claim 1, wherein the middle plate and bottom plate are combined as a single plate.
Claim 4
Dependent Claim 87 words
An actuator according to claim 1, wherein the piston comprises a head and a shaft and the middle plate comprises an edge, two chambers and at least one channel leading from the edge to the first chamber which comprises two ends and is adapted to receive the head of the piston and permit displacement of the piston head between the two ends of the first chamber; and wherein one end of the first chamber connects to a second chamber into which the shaft of the piston extends.
Claim 5
Dependent Claim 25 words
An actuator according to claim 3, wherein the actuator is no more than 3 centimeters in width and no more than 5 centimeters in length.
Claim 6
Dependent Claim 24 words
An actuator according to claim 4, which produces a force of at least 4 kilograms and a displacement of at least a half centimeter.
Claim 7
Dependent Claim 14 words
An actuator according to claim 1, wherein the chamber is coated with a sealant.
Claim 8
Dependent Claim 26 words
An actuator according to claim 1, wherein the piston is coated with a sealant that enables the piston to slide within the chamber with low friction.
Claim 9
Independent Claim 131 words
A method of producing a layered hydraulic actuator comprising the steps of (a) forming top, bottom, and middle plates, wherein the middle plate has a cut-out first chamber and an adjoining second smaller chamber, (b) inserting a piston having a head and a shaft into the chambers of the middle plate such that it can slide back and forth within the chambers, the head of the piston being housed in the first chamber and the shaft being housed in the second chamber, (c) forming at least one channel in the middle plate to conduct hydraulic fluid into said first chamber, and (d) joining said lower, middle, and upper plates in a stacked arrangement, such that the first chamber of the middle plate is enclosed to form a cavity containing the piston.
Claim 10
Independent Claim 131 words
A method of producing a layered hydraulic actuator comprising the steps of (a) forming top, bottom, and middle plates, wherein the middle plate has a cut-out first chamber and an adjoining second smaller chamber, (b) inserting a piston having a head and a shaft into the chambers of the middle plate such that it can slide back and forth within the chambers, the head of the piston being housed in the first chamber and the shaft being housed in the second chamber, (c) forming at least one channel in the middle plate to conduct hydraulic fluid into said first chamber, and (d) joining said lower, middle, and upper plates in a stacked arrangement, such that the first chamber of the middle plate is enclosed to form a cavity containing the piston.
Claim 11
Dependent Claim 39 words
A method according to claim 8, further comprising the steps of (e) coating the piston with a liquid, (f) inserting the piston into the first chamber, and (g) causing the liquid to solidify into a coating around the piston.
Claim 12
Dependent Claim 37 words
A method according to claim 8, further comprising the steps of (e) introducing a liquid into the first chamber after introducing the piston therein, and (f) causing said liquid to solidify into a coating around the piston.
Claim 13
Dependent Claim 72 words
A method according to claim 8, further comprising the steps of (e) forming a groove in each of said upper, middle, and lower plates which circumscribes said chambers and said at least one channel, (f) filling said grooves with a fluid, (g) assembling said actuator, and (h) causing said fluid to solidify, whereby the solidified fluid provides a seal to prevent leakage of hydraulic fluid conducted by said at least one channel.
Claim 14
Dependent Claim 13 words
A method according to claim 11, wherein the seal-forming fluid is castable rubber.
Claim 15
Dependent Claim 48 words
A method according to claim 8, further comprising the following steps which are performed prior to step (d) of claim 8: providing grooves in the top and bottom plates which circumscribe the slots and channels of the middle plate and then introducing a gasket-forming liquid into said grooves.
Claim 16
Dependent Claim 34 words
A method according to claim 8, wherein, prior to step (b) of claim 8, the piston is coated with a sealant that permits the piston to slide within the piston chamber with low friction.

References Cited (Backward Citations)

US4267758A Cited
US4763669A Cited
US4848338A Cited
US4988981A Cited
US4988981B1 Cited
US5142930A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-08-10 2002-02-09 2002-08-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-08-10 2006-02-09 2006-08-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-08-10 2010-02-09 2010-08-11 $7700.00 Window Closed / Lapsed

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