Bear-loc load-holding and locking system for hydraulic systems

Abstract

A rod locking device for holding a load or locking a hydraulic system includes a rod having an outside diameter enclosed in a sleeve having an inside diameter as well as optional liners between these diameters which form an interference fit. The interference fit configured to provide a positive mechanical connection to lock the rod in any phase of the stroke within the sleeve. The sleeve configured to expand radially as soon as hydraulic pressure is applied, thereby removing the interference and creating enough clearance for the rod to freely stroke within the sleeve and when hydraulic pressure is removed the interference fit prevents movement of the rod relative to the sleeve due to the interference fit.

Description

Attorney Docket No.: 690017.0003 / 1WOTITLE OF THE INVENTIONBear-Loc Load-Holding and Locking System for Hydraulic SystemsBACKGROUND OF THE INVENTION

[0001] Load-holding and locking in hydraulic systems is accomplished in a variety of ways. When the potential failure of a hydraulic system represents a safety concern (injury, loss of life) and / or a performance concern (damage or loss of materials, equipment damage / failure, costly downtime, mission failure) there is a clear need for a fail-safe solution. A fail-safe solution is one that continues to hold the rated load capacity even if hydraulic pressure is removed, whether accidentally or on purpose.

[0002] Load-holding and locking devices that are positive locks, meaning that they lock when pressure is removed, may accomplish the locking action by a mechanical device, such as clamping or by a physical pinning action at predetermined locations along the rod. Some of these types of solutions need to move into locking position and do not instantly lock if pressure is lost, which is undesirable. Another problem with these types of mechanical devices is that over time, the parts will wear and eventually risk dropping the load. The wear may not be readily apparent to users and failure may occur.

[0003] A further risk presents itself in the form of operating complexity of many devices. Incorrect operation can mean injury and equipment damage. Hydraulic locking mechanisms can also be troubled by leaking and hydraulic fluid flow issues which can impair operation. These devices are often limited in the range of equipment size and weights that can be safely held. These hydraulic locking mechanisms and systems may also be limited by environmental factors and application requirements, such as exposure to corrosive environments, extreme temperatures, and marine or subsea environments. There is also a need for an innovative design that can effectively connect with a wide variety of existing hydraulic systems. In fact, there are limitations to availability of failsafe designs to various industries and applications. The design and method of production of the preferred present invention address these shortcomings in the prior art and produces a fail-safe lock that does not require the above-described mechanical devices or the hydraulic locking mechanisms.BRIEF SUMMARY OF THE INVENTION

[0004] In response to the need in the art for a fail-safe device or a device that will not drop its load even when power or pressure loss occurs, the preferred present invention accomplishes its fail-safe positive lock capability via interference fit, based on the principle of elastic expansion. The preferred invention is comprised of very few parts and is simple to operate. The preferred invention consists of a rod, sleeve, optional liners, and end caps with special customizable ports. The rod is installed inside the sleeve. The sleeve inside diameter (“ID”) is smaller than the rod outer diameter (“OD”). The end caps are added to create a closed system. Application of hydraulic pressure inside the device enlarges the sleeve just enough so that the rod can move freely or is at least slidable within the sleeve. When hydraulic pressure is removed, the sleeve locks onto the rod, quickly or preferably instantly, delivering a high performance, long-life, fail-safe result to a wide variety of applications. The addition of liners, which are metal split rings with engineered radial grooves between the rod and sleeve within the preferred invention, provide performance and reliability advantages for a wider array of applications. This option requires an anti-rotation rod which prevents the liners from significant rotation and keeps the grooves (“fluid channels”) open for proper operation. With proper operation little or no wear occurs.

[0005] The specialized incorporation of other components such as valves, transducers, and sensors provides an extra layer of reliability, flow control, and a level of automation for lock operation. Incorporating these items provides digital logic directly to the unit, thereby minimizing the customer’s need for system knowledge or training. Valve integration also significantly expands the range of potential applications and environments, including those which make human intervention difficult or impossible, such as nuclear environments, wind and storm exposures, limited access above and below ground, as well as above and below water. Specialized incorporation of these components provides very specific data without requiring human intervention.

[0006] Process enhancements unique to the preferred invention include a ferritic nitrocarburization treatment of the bear-loc rod for corrosion resistance enhancement. This is an environmentally safer option than the chromium approach typically used in the industry. This specialized treatment achieves significantly better product performance interms of reliability and longevity, reducing wear and optimizing product performance in challenging operating environments such as very extreme temperatures, highly corrosive marine and subsea environments, and high pollution and particulate regions (e.g. desert sand).

[0007] A specialized machining process used in the preferred invention creates smooth edges on fluid channels to protect treated or plated rods from burrs. Wire electrical discharge machining (“EDM”) may be used to cut linear grooves in the sleeve of the non-liner version of the bear-loc. Wire EDM is preferred over broaching methods used for the prior versions for cutting the sleeve.

[0008] Other enhancements include:• a threaded sleeve design which enhances integration with existing hydraulic cylinders;• the piston lock version in which the bear-loc feed tube goes through the piston and creates a fluid channel to supply the bear-loc section with pressure separate from the extend and retract side of the hydraulic cylinder;• a piston lock version with internal valving to combine the bear-loc and actuator ports which further enhances the versatility of the preferred invention;• the addition of a self-contained compact hydraulic power unit makes possible the use of the preferred invention in applications that otherwise lack sufficient hydraulic pressure and enhances its use in mobile applications;• a 3D printed sleeve version that allows the standard carbon steel to be replaced by a version created by additive manufacturing;• a composite sleeve version that makes use of alternate materials besides the standard steel to create a sleeve that has the same characteristics without the use of metal; and• a stainless steel version of the sleeve that departs from the standard carbon steel offering in a way that makes it more corrosion resistant.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0009] The foregoing summary, as well as the following detailed description of preferred embodiments of the system and method of the preferred embodiments of thepresent invention, will be better understood when read in conjunction with the appended drawings. For the purposes of illustrating the bear-loc load-holding and locking system for hydraulic systems, there are shown in the drawings preferred embodiments. It should be understood, however, that the application is not limited to the precise arrangements and instrumentalities shown. In the drawings:

[0010] Fig. 1 illustrates a cutaway side perspective view of a bear-loc rod lock in accordance with a first preferred embodiment of the present invention, showing a rod, a sleeve, optional liners, end caps, and customizable ports;

[0011] Fig. 1A illustrates a cross-sectional view of the bear-loc rod lock of Fig. 1, taken along line 1A-1A of Fig. 1;

[0012] Fig. IB illustrates a side perspective view of a liner of the bear-loc rod lock of Fig. 1;

[0013] Fig. 1C illustrates a front elevational view of the liner of Fig. IB;

[0014] Fig. 2 illustrates a cutaway side perspective view of the bear-loc rod lock ofFig. 1, including an anti -rotation rod as well as the liners which are split rings with engineered grooves;

[0015] Fig. 2A illustrates a cross-sectional view of the bear-loc rod lock of Fig. 2, taken along line 2A-2A of Fig. 2;

[0016] Fig. 3 illustrates a cross-sectional view of a bear-loc piston locking device or system in accordance with an alternative or second preferred embodiment of the present invention, showing passage of hydraulic fluid straight through a piston via a feed tube to achieve a longer stroke;

[0017] Fig. 3 A illustrates a cutaway side perspective view of the bear-loc piston locking device or system of Fig. 3;

[0018] Fig. 4 illustrates a side perspective view of integration of specialized valves and digital controls with the bear-loc rod lock system of Fig. 1;

[0019] Fig. 5 illustrates a side perspective view of a one-piece sleeve design of the bear-loc rod lock of Fig. 1, with an alternative preferred efficient threading adapter;

[0020] Fig. 5 A illustrates a side perspective view of the bear-loc rod lock of Fig. 5, wherein a cylinder is attached to the threading adapter;

[0021] Fig. 5B illustrates a cross-sectional view of the bear-loc rod lock of Fig. 5, taken along line 5B-5B of Fig. 5;

[0022] Fig. 6 illustrates a cross-sectional view of an internal valving enhancement (piston lock with internal valving) for the bear-loc piston lock of the preferred embodiments;

[0023] Fig. 7 illustrates a side elevational view of a self-contained compact hydraulic power unit designed for use with the bear-loc rod lock of the preferred embodiments;

[0024] Fig. 7A illustrates a cross-sectional view of the self-contained compact hydraulic power unit of Fig. 7, taken along line 7A-7A of Fig. 7;

[0025] Fig. 8 illustrates a side perspective, partial cross-sectional view of a bear-loc rod lock in accordance with an alternative preferred embodiment, showing a 3D printed sleeve compared to a traditionally manufactured carbon steel sleeve;

[0026] Fig. 8A illustrates a side perspective, partial cross-sectional view of the bear- loc rod lock of Fig. 8, highlighting the printed sleeve in cross-hatch;

[0027] Fig. 9 illustrates a side perspective view of a sleeve of a bear-loc rod lock that uses EDM processes to enhance the system;

[0028] Fig. 9A illustrates a cross-sectional view of the sleeve of Fig. 9, taken along line 9A-9A of Fig. 9;

[0029] Fig. 9B illustrates a side elevational view of the sleeve of Fig. 9;

[0030] Fig. 9C illustrates a cross-sectional view of the sleeve of Fig. 9, taken along line 9C-9C of Fig. 9B;

[0031] Fig. 10 illustrates a side perspective, partial cross-sectional view of a bear-loc rod lock in accordance with an additional alternative preferred embodiment of the present invention, showing a composite sleeve for use with the preferred embodiments of the bear-loc rod lock;

[0032] Fig. 10A illustrates a side perspective, partial cross-sectional view of the bear- loc rod lock of Fig. 10, wherein the sleeve is highlighted in cross-hatch;

[0033] Fig. 11 illustrates a side perspective view of a rod for the bear-loc rod lock of the preferred embodiments, wherein the rod is treated by ferritic nitrocarburizing (“FNC”), such as melonite FNC;

[0034] Fig. 11 A illustrates a side perspective view of the rod of Fig. 11, wherein the rod is treated with a nitrate case hardening process;

[0035] Fig. 12 illustrates a side perspective, partial cross-sectional view of a further preferred embodiment of the bear-loc rod lock having a stainless steel sleeve that may be utilized as an alternate material with the preferred bear-loc rod lock sleeve; and

[0036] Fig. 12A illustrates a side perspective, partial cross-sectional view of the sleeve of Fig. 12, wherein the sleeve is highlighted by cross-hatch.DETAILED DESCRIPTION OF THE INVENTION

[0037] Certain terminology is used in the following description for convenience only and is not limiting. Unless specifically set forth herein, the terms “a”, “an” and “the” are not limited to one element but instead should be read as meaning “at least one”. The words "right," "left," "lower" and "upper" designate directions in the drawings to which reference is made. The words "inwardly" and "outwardly" refer to directions toward and away from, respectively, the geometric center of the preferred bear-loc rod lock or the bear-loc load-holding and locking system for hydraulic systems and related parts thereof. The terminology includes the above-listed words, derivatives thereof and words of similar import.

[0038] It should also be understood that the terms “about,” “approximately,” “generally,” “substantially” and like terms, used herein when referring to a dimension or characteristic of a component of the preferred invention, indicate that the described dimension / characteristic is not a strict boundary or parameter and does not exclude minor variations therefrom that are functionally the same or similar, as would be understood by one having ordinary skill in the art. At a minimum, such references that include a numerical parameter would include variations that, using mathematical and industrial principles accepted in the art (e.g., rounding, measurement or other systematic errors, manufacturing tolerances, etc.), would not vary the least significant digit.

[0039] Referring to Figs. 1-2A, a bear-loc device or bear-loc rod lock, generally designated 10, includes a rod 12 and optional liners 14 enclosed with end caps 18 and slidably mounted in a cylindrical sleeve 16 which forms an interference fit with an outside diameter OD of the rod 12. This interference fit provides a positive mechanicalconnection to lock the rod 12 in any phase of the stroke of the rod 12. As soon as hydraulic pressure is applied, the sleeve 16 expands radially, preferably and specifically an inside diameter ID of the sleeve 16 expands radially, removing the interference fit between the rod 12 and the sleeve 16 and creating enough clearance for the rod 12 to be freely stroked within the sleeve 16. When hydraulic pressure is removed, the bear-loc rod lock or rod locking device 10 engages quickly, preferably nearly instantly, with limited to no drift as the sleeve 16 retracts radially onto the rod 12. The bear-loc rod locking device 10 locks quickly or automatically when pressure is removed from the sleeve 16. Whether pressure is removed on command, or if pressure is lost, the bear-loc rod locking device 10 will engage quickly or automatically providing a reliable, positive, and fail-safe locking device with the sleeve 16 engaging the rod 12 to limit or stop movement of the rod 12 along a longitudinal axis 12a. The bear-loc rod locking device 10 does not depend on moving parts, valves, or other components to obtain its positive mechanical lock between the sleeve 16 and the rod 12. The bear-loc rod locking device 10 features infinite positioning and bi-directional locking. That is, the rod 12 can be engaged by the sleeve 16 and locks in any position along its stroke, and motion is nearly impossible in any direction when the bear-loc rod locking device 10 is engaged and operated within its rated capacity. In the preferred embodiments, when hydraulic pressure is lost an interference fit occurs between the sleeve 16, the liners 14, and the rod 12. The bear-loc rod locking device 10 is not limited to including the liners 14 and the liners 14 are not always present in the assembly and the bear-loc rod locking device 10 may operate effectively without inclusion of the liners 14.

[0040] The preferred liners 14 include grooves 14a and a split 14b. The split 14b is configured to facilitate expansion of the liners 14 within the sleeve 16 and disperse fluid between the rod 12 and the sleeve 16. The preferred grooves 14a extend circumferentially around an outside surface of the liners 14 and an inside surface of the liners 14 and open at their ends into the split 14b. The grooves 14a are not limited to being positioned on outside and inside surfaces of the liners 14 and may be otherwise designed and configured.

[0041] To ensure proper hydraulic fluid flow within the sleeve 16 of the bear-loc rod locking device 10 with liners 14, an anti -rotation rod 20 is included in the assembly. Theanti-rotation rod 20 is preferably comprised of a small diameter cylindrical steel rod that is inserted into the assembly of the bear-loc rod locking device 10. The anti-rotation rod 20 is placed in a channel 22 that is formed when the liners 14 are all oriented the same way rotationally between the rod 12 and the sleeve 16. This configuration prevents the liners 14 from rotating within the sleeve 16 and acts as a fluid channel that allows for flow of hydraulic fluid within the sleeve 16 along gaps between the channel 22, the liners 14 and the anti-rotation rod 20. If the liners 14 are rotatable, then the fluid channel could be restricted causing an interruption of adequate fluid flow. From the channel 22 formed by the anti -rotation rod 20, the hydraulic fluid can then pass to grooves 14a in the liners 14 that create another channel in which the hydraulic fluid can flow. With the addition of the anti -rotation rod 20, the flow of hydraulic fluid is better controlled and allows a greater fill in the sleeve 16 to allow for smoother expansion of the sleeve 16.

[0042] Referring to Figs. 3 and 3A, in an alternative preferred embodiment a bear-loc piston locking device 11, has similar features to the bear-loc rod locking device 10 and utilizes the principles of elastic expansion to lock. The bear-loc piston locking device 11 may include a hydraulic fluid feed tube 24 added to the center of a hydraulic cylinder that extends through the rod 12. The feed tube 24 uses a separate bear-loc port 17 on a cylinder 19, which is generally equivalent to the sleeve 16 and allows hydraulic fluid to flow internally in the cylinder 19 but remain separate from the extend and retract cavity sides of the piston 15. Once the fluid enters the fluid feed tube 24, the fluid is then directed to a sealed off portion over the face of the piston 15. This allows the piston style bear-loc piston locking device 11 to operate without the need for porting in through the side of the cylinder 19 or sleeve 16. This also allows an increase to a length of the stroke of the cylinder 19 because limitations related to the length of the piston 15 and location of the port 17 are generally eliminated. This improvement in the delivery of hydraulic fluid internally can be used on multiple sizes of bear-loc piston locking devices 11 or the bear- loc rod locking devices 10. Liners 14 may be positioned between the piston 15 and the cylinder 19 or sleeve 16 in the assembled configuration, although in this alternative preferred embodiment that bear-loc piston locking device 11 is liner-less. Fig. 3, however, includes an identification of where the liners 14 would be located if they were included in the bear-loc piston locking device 11 of the alternative preferred embodiment.

[0043] Referring to Fig. 4, specialized valves and digital controls may be integrated into the bear-loc rod locking device 10. Internal valving may be incorporated within the end caps 18 of the bear-loc rod locking device 10 or blocks 26 on hydraulic cylinders 35 attached to the bear-loc rod locking device 10 that allows the addition of extra features the customer may want besides the standard bear-loc rod locking device 10 on the hydraulic cylinder 35. On some applications flow fuses 28a and counterbalance valves 28b may be added directly into the blocks 26 on the hydraulic cylinder 35. Including the flow fuses 28a and the counterbalance valves 28b permits an extra layer of safety, as there are now two safety devices implemented within the same cylinder 35. Proximity sensors 30 may also be incorporated into the blocks 26 on the hydraulic cylinder 35 or the end caps 18 on the bear-loc rod locking device 10 such that the user is able to see where the rod 12 is positioned within its stroke. This allows greater transparency and control of the hydraulic cylinder 35, which allows for a more efficient end user experience and superior system integration. The bear-loc rod locking device 10 may also include actuators 37 that may be configured to facilitate load holding, position sensing, end-of- stroke signaling, and enhanced user integration and efficiency.

[0044] Referring to Figs. 5-5B, a one-piece design for the sleeve 16 may be incorporated into the bear-loc rod locking device 10. A rod lock style bear-loc may be utilized as a self-contained unit and is able to attach via threading 16a directly onto a prefabricated hydraulic cylinder 35. Using an existing hydraulic cylinder 35, a rod end block may be modified so that the bear-loc sleeve 16 can thread onto the prefabricated cylinder 35. This configuration uses the existing rod and gives the hydraulic cylinder 35 a locking feature which the hydraulic cylinder 35 previously did not have. This preferred sleeve 16 of the bear-loc rod locking device 10 is preferably self-contained and features seals on both ends so the prefabricated cylinder 35 to which the preferred sleeve 16 attaches can use its original seals, generally without modification.

[0045] Referring to Fig. 6, an internal valving enhancement may be incorporated into the second or alternative preferred bear-loc piston locking device 11. The use of internal valving within the bear-loc piston locking device 11 allows a reduction in the number of external ports on the hydraulic locking cylinder 16 from a standard three (3) ports down to only two (2) ports. Normally, the hydraulic locking cylinder 16 incorporating a priorart bear-loc system includes the standard extend and retract ports as well as a third port for locking and unlocking the system (not shown). Most prior art systems that are using a non-locking cylinder are using two lines which are the extend and retract lines. The ability to remove the third port on the preferred bear-loc piston locking device, system or design 11 allows integration with existing designs seamlessly, as a third port does not have to be incorporated and the existing two ports can be quickly connected and / or disconnected. This configuration can be incorporated using multiple internal one-way valves or internal valving 13 in the piston 15 that allow the fluid to move in such a way that the lock stays open when needed and certain pressure balances inside the cylinder or sleeve 16 can be maintained. When the pressure is lost, either intentionally or accidentally, the cylinder or sleeve 16 will retract and the lock will engage to generally prevent movement of the piston 15 and rod 12 within the cylinder or sleeve 16. Through this process, the locking of the bear-loc piston locking device 11 is retained, while concurrently opening a range of applications within the industry for compatibility with additional systems that function with the two ports.

[0046] Referring to Figs. 7 and 7A, a self-contained compact hydraulic power unit 32 may be utilized or attached to the bear-loc rod locking device 10. Since the preferred bear-loc rod locking device 10 operates via hydraulic fluid pressure, the self-contained compact hydraulic power unit 32 may be implemented to unlock the bear-loc rod locking device 10 in an area where hydraulic power is not readily available. The preferred bear- loc rod locking device 10 uses limited fluid in operation, therefore only a small amount of fluid needs to be displaced for the lock between the rod 12 and the sleeve 16 to open and close. As a non-limiting example, the locking device 10 may utilize approximately one one-hundredth cubic inches (0.01 in3) of fluid per inch (1”) of rod diameter times a length of the lock. The self-contained compact hydraulic power unit 32 is preferably lightweight and portable and is comprised of a reservoir 32a, electric motor 32b, pump 32c, solenoid 32d, valve block 32e, pressure transducer 32f, pressure gauge 32g, pressure relief valve 32h, battery 32i, hoses 32j, voltage converter 32k, controller 321, and accompanying wiring 32m to produce the hydraulic pressure to unlock the bear-loc rod locking device

[0047] Referring to Figs. 8 and 8A, the bear-loc rod locking device 10 may incorporate a three-dimensional (“3D”) printed sleeve 34 that replaces the sleeve 16. An arc / wire 3D printer (not shown)may be utilized to manufacture the 3D printed sleeve 34 compared to traditional machining that is typically utilized to manufacture the sleeve 16. Laser powder-bed 3D printing methods may also be used to 3D print the 3D printed sleeve 34. This allows the use of additive manufacturing to construct the 3D printed sleeve 34, instead of subtractive manufacturing, which is typically utilized to construct the sleeves 16 and prior art sleeves. The ability to 3D print the sleeve 34 allows achievement of a wider range of desired material properties that are enhancements to the bear-loc rod locking device 10.

[0048] Referring to Figs. 9-9C, the EDM process may be utilized to enhance the bear-loc rod locking device 10. Traditionally, broaching is utilized to cut axial grooves 16a in linerless sleeves. Using EDM to complete this process allows tighter tolerances compared to broaching. When grooves 16a in the sleeve 16 are cut more accurately, the need for secondary processes to knock the edges off the axial grooves 16a are generally eliminated. With the simplification of the processing, chrome on the rod 12 is protected, because of the reduced number of sharp edges on the inside diameter of the sleeve 16 that may result from the grooves 16a.

[0049] Referring to Figs. 10 and 10A, the sleeve 16 may be constructed of several alternative materials. As a non-limiting example, composite material may be utilized to manufacture the sleeve 16. The composite material allows production of the sleeve 16 at a lower cost compared to using traditional steel. The preferred composite material may slightly lower the capacity of the bear-loc rod locking device 10 when compared to steel sleeves 16, but the composite sleeve 16c is generally more cost effective. The composite sleeve 16c may also be limited in length. The use of steel and / or composite sleeves 16, 16c allows multiple options based on a customer’s specific needs.

[0050] Referring to Figs. 11 and 11 A, ferritic nitrocarburizing (“FNC”) may be utilized for treating the rod 12. The FNC may be comprised of a melonite FNC that is utilized to surface harden the rod 12 to improve wear, corrosion and fatigue resistance of the rod 12. Using the FNC heat treatment finish as compared to traditional chrome plating on the rod 12 provides improvements. Utilizing the FNC process on the rod 12produces a high surface hardness and improved wear resistance of the material of the rod 12, as well as corrosion resistance. The FNC process is also considered an improvement for the environment, particularly when compared to chrome plating. Typically, FNC is a more budget friendly process compared to chrome plating. FNC is further generally less reflective than chrome so the customers who are looking for a non-reflective finish on the rod 12, such as military applications may prefer to utilize the FNC process. The rod 12 is not limited to utilizing FNC treatments and may be configured to include the chrome plating or other treatments that are able to withstand the normal operating conditions of the rod 12 and perform the preferred functions of the rod 12, as is described herein and would be apparent to one having ordinary skill in the art based on a review of the present disclosure.

[0051] Referring to Figs. 12 and 12A, the bear-loc rod locking device 10 may also utilize various additional materials to enhance the sleeve 16. Carbon steel is typically used as the sleeve material because the carbon steel has the desired material properties to achieve the lock function. Alternatively, stainless steel may be utilized as the material for the sleeve 16 that has the desired properties for the lock function. The stainless steel material may improve the structural tolerances required for the sleeve 16 and may reduce costs and manufacturability of the sleeve 16. Stainless steel also has many anti-corrosion properties when compared to traditional carbon steel, this is important when the bear-loc rod locking device 10 is being used in a corrosive environment such as high humidity or subsea applications.

[0052] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the present description.

Claims

CLAIMSWe claim:

1. A rod locking device for holding a load or locking a hydraulic system, the rod locking device comprises: a rod having an outside diameter; a sleeve having an inside diameter, the rod positioned within the sleeve in an assembled configuration, the rod and the sleeve defining an interference fit with the outside diameter engaging the inside diameter in the assembled configuration, the interference fit configured to provide a positive mechanical connection to lock the rod in any phase of a stroke of the rod within the sleeve, the sleeve configured to expand radially when hydraulic pressure is applied between the sleeve and rod thereby removing the interference fit and creating clearance for the rod to freely stroke within the sleeve, the interference fit also configured such that when hydraulic pressure is removed the interference fit blocks movement of the rod relative to the sleeve due to the interference fit; and liners positioned between the rod and sleeve in the assembled configuration.

2. The rod locking device of claim 1, wherein an anti -rotation rod is positioned in a channel that is formed when the liners are oriented in a mounted configuration rotationally between the rod and the sleeve, the anti-rotation rod is configured to prevent the liners from rotating within the sleeve and define a fluid channel that allows flow of hydraulic fluid within the channel.

3. The rod locking device of claim 2, wherein the anti-rotation rod is comprised of a small diameter cylindrical steel rod4. The rod locking device of claim 1, wherein the liners include grooves and a split, the split configured to facilitate expansion of the liners with the sleeve and disperse fluid between the rod and the sleeve.

5. The rod locking device of claim 1, further comprising: end caps mounted to ends of the sleeve; andinternal valving and sensors positioned within the blocks; and actuators configured to facilitate load holding, position sensing, end-of-stroke signaling, and enhanced user integration and efficiency.

6. The rod locking device of claim 5, wherein internal valving is configured to allow reduction of a number of external ports.

7. The rod locking device of claim 6, wherein the reduction is from three ports to two ports.

8. The rod locking device of claim 1, further comprising: an end cap mounted to an end of the sleeve, threading positioned on the end cap, the threading configured for attaching to a prefabricated hydraulic cylinder.

9. The rod locking device of claim 1, further comprising: a self-contained compact hydraulic power unit powered by an internal battery, the self-contained compact hydraulic power unit configured to unlock the interference fit by introducing the hydraulic pressure.

10. The rod locking device of claim 9, wherein the self-contained compact hydraulic power unit is small and portable.

11. The rod locking device of claim 1, wherein the sleeve is configured for manufacturing by one of a powder bed laser sintering 3D printer and an arc / wire 3D printer.

12. The rod locking device of claim 1, wherein wire electrical discharge machining is utilized to cut axial grooves in the sleeve.

13. The rod locking device of claim 1, wherein the sleeve is constructed of a composite material.

14. The rod locking device of claim 1, wherein the rod includes a ferritic nitrocarburizing heat treatment finish.

15. The rod locking device of claim 1, wherein the sleeve is constructed of a stainless-steel material, the stainless steel material having material properties for achieving the interference fit between the sleeve and rod.

16. The rod locking device of claim 1, wherein the liners have an outside liner diameter and an inside liner diameter, the liners configured for mounting between the outer diameter of the rod and inner diameter of the sleeve.

17. A piston locking device for holding a load or locking a hydraulic system, the rod locking device comprising: a piston having an outside diameter; a sleeve having an inside diameter, the piston and the sleeve defining an interference fit with the outside diameter engaging the inside diameter in an assembled configuration; a hydraulic fluid feed tube positioned in a center of the piston, the feed tube releasably mountable to a port which is configured to allow hydraulic fluid to flow internally in the piston but remain separate from sides of the piston within the sleeve, the sleeve configured to expand radially when hydraulic pressure is applied between the sleeve and piston thereby removing the interference fit and creating clearance for the piston to move generally parallel to a longitudinal axis of a rod attached to the piston within the sleeve and the interference is engaged when the hydraulic pressure is removed.

18. The rod piston device of claim 17, wherein the piston includes radially extending tubes between the hydraulic feed tube and the outside diameter.

19. The piston locking device of claim 17, further comprising: end caps mounted to ends of the sleeve.

20. The piston locking device of claim 17, wherein the hydraulic fluid feed tube extends from a first end of the piston to a central portion of the rod.

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