The present invention relates to an elongated telescopic device according to the preamble of claim 1. The present invention also relates to a method for operating the telescopic device. The present invention may concern the industry using hydraulic and/or pneumatic actuators for different types of applications and may also concern the manufacture industry producing telescopic devices.
The invention may relate to elongated telescopic devices comprising single acting and/or double acting fluid actuator assemblies.
The present invention may be put into use in mobile cranes or mobile drilling apparatus vehicles.
Current fluid actuator assemblies used in telescopic devices are bulky and heavy. There are several telescopic devices designed trying to solve such problems. Prior art telescopic devices are also slow and labour intensive to extend.
U.S. Pat. No. 3,804,262 shows a telescopic device of a mobile crane having telescopic hollow boom sections, in which there are arranged a respective hydraulic actuator for propulsion of the boom sections for extension and retraction.
U.S. Pat. No. 5,628,416 shows a telescopic device of a mobile crane having telescopic boom members and a single stage piston and cylinder unit and locking bolts for coupling each boom member to the actuator unit for extension and retraction.
U.S. Pat. No. 5,632,395 shows a telescopic device of a mobile telescopic crane having a multistage simple-acting piston-cylinder unit arranged for extending the telescopic crane. A steel rope is provided for retracting the telescopic crane.
There is an object to provide a compact and lightweight elongated telescopic device of the type defined in the introduction.
There is also an object to provide a compact and lightweight elongated telescopic device that can be extended and retracted in an energy efficient way. There is an object to reach more efficient control of speed and force of an elongated telescopic device.
Yet another object is to reduce power output of associated fluid supply device of an elongated telescopic device.
There is also an object to reduce energy losses.
An object is to improve current elongated telescopic devices in mobile and industrial applications.
An object is to provide an elongated telescopic device to accomplish work with only a small amount of input force.
An object is to provide an elongated telescopic device that is energy-efficient and fast to extend.
A further object is to provide an elongated telescopic device, which can be used in smart fluid power component systems including self-diagnostics and plug-and-play (easy to use) functionality.
A further object is to provide an elongated telescopic device, which can be used in modular systems comprising standardized fluid actuator assembly units having standardized piston bodies.
This or at least one of said objects has been achieved by an elongated telescopic device comprising a support element formed to partly or entirely encompass (nestled) first and second telescopic element mounted so as to be telescopically slidable relative each other in an longitudinal direction; the support element comprises a support element fluid actuator assembly; the first telescopic element is arranged to encompass the second telescopic element and comprises a first fluid actuator assembly; characterized in that the support element fluid actuator assembly is fixed to an interior portion of the support element and is arranged for engagement or disengagement to a first envelope surface of the first telescopic element; and in that the first fluid actuator assembly is fixed to a first interior portion of the first telescopic element and is arranged for engagement or disengagement to a second envelope surface of the second telescopic element.
Thereby is achieved that the elongated telescopic device can be made lightweight and compact since the encompassed telescopic element (hollow boom) is used as a piston rod moved by the fluid actuator assembly simultaneously as it is used as a telescopic element. Thereby is provided that the elongated telescopic device operates in an energy efficient way.
The piston rod engagement and disengagement device
Preferably, a second fluid actuator assembly is fixed to a second interior portion of the second telescoping element and is arranged for engagement or disengagement to a third envelope surface of a third telescoping element.
Thereby is achieved that the third telescoping element can moved into or out from the second telescoping element. Preferably, the inner portion of the telescoping element (first, second, third) may be an inner wall of the telescoping element.
Suitably, the elongated telescopic device comprises a plurality of telescoping elements mounted so as to be telescopically slidable relative each other, each telescoping element comprises a fluid actuator assembly arranged for engagement with (clamping to) an adjacent telescoping element.
Thereby is provided a relatively long telescopic device that can be used as a crane boom or other arm member.
Preferably, a bearing member is arranged between two adjacent telescoping elements, which bearing member comprises bronze alloy and/or tin bronze and/or lead free bronze and/or copper and/or aluminium-bronze and/or carbon graphite.
Thereby is achieved that the telescoping elements slides with decreased friction.
Suitably, the telescoping element exhibits a circular cross-section.
Thereby is achieved that the respective telescoping element can be used as a boom or arm member per se, wherein the respective telescoping element features a hollow piston rod section.
Preferably, at least one fluid actuator assembly comprises a first cylinder chamber and a first piston body having a first expandable hollow space provided for fluid communication with the first cylinder chamber so as to provide (a clamping action) engagement with an envelope surface of an inside positioned telescopic element.
Preferably, the first piston body is slidably arranged in a cylinder housing and divides the cylinder housing into a first cylinder chamber and a second cylinder chamber.
Suitably, first chamber is pressurized with a first pressure, whereby the first piston body will be in engagement with the envelope surface of the adjacent positioned telescopic element.
Preferably, the first pressure is transferred directly to the first expandable hollow space so as to expand a first expandable clamping wall of the first piston body.
Suitably, a first engagement and disengagement device of the first piston body comprises the first expandable hollow space and the first expandable clamping wall.
Preferably, the first pressure is transferred from the first cylinder chamber to the first expandable hollow space via a channel system of the first piston body.
Suitably, the channel system comprises an opening facing the first cylinder chamber and comprises a further opening entering the first expandable hollow space.
The first engagement and disengagement device of the first piston body is thus directly controlled by the first pressure of the pressurized first cylinder chamber, wherein said first pressure also acts on the first expandable clamping wall for expansion toward the envelope surface of the adjacent telescopic element for providing said clamping action.
Suitably, the first expandable clamping wall expands in radial direction toward the envelope surface of the adjacent positioned telescopic element and clamps around said envelope surface.
Preferably, the first engagement and disengagement device is rigidly fixed to the first piston body.
The first pressure of the pressurized first cylinder chamber acts on the first piston body, for moving the first piston body in axial direction together with the adjacent telescopic element, as the first piston body clamps on the envelope surface of the adjacent telescopic element when the first expandable hollow space also is pressurized.
The first engagement and disengagement device will thus upon pressurizing of the first chamber be engaged with the adjacent telescopic element by means of the first pressure pressing the expandable clamping wall (membrane) in radial direction towards the envelope surface of the adjacent telescopic element.
There is thus achieved that engagement between the envelope surface of the adjacent telescopic element and the first piston body is performed directly and promptly without any additional mechanical parts.
Thereby is provided that the engagement and disengagement device can be controlled by the same control device (control valve device and control unit), which control device also controls the movement of the first piston body relative the cylinder housing by pressurization of the respective cylinder chamber.
Preferably, the first fluid actuator assembly comprises said first piston body, said first cylinder housing, said first engagement and disengagement device and second fluid actuator assembly comprising a second piston body, a second cylinder housing, a second engagement and disengagement device.
Suitably, the second piston body thus comprises the second engagement and disengagement device adapted to be able to engage or disengage the second piston body to/from the envelope surface of said adjacent telescopic element in a similar way as described for the first piston body.
The first and second piston body of the first fluid actuator assembly acts alternately for propelling the adjacent telescopic element.
Preferably, the (first, second etc.) hollow space is entirely sealed and provided in a sealed manner within the (first, second etc.) piston body, so that no fluid is permitted to leak to the contact surface of the piton body and the envelope surface of the encompassed telescopic element.
Thereby is achieved an optimal and reliable functionality providing accurate performance of the fluid actuator arrangement.
Thereby is provided a compact and low-weight (and energy saving) fluid actuator arrangement that can propel the adjacent telescopic element a major distance and back again, wherein the respective first and second piston body in turn is engaged with the adjacent telescopic element.
Thereby is achieved a membrane that can be used as a coupling device between the piston rod and the piston device.
Preferably, the proportion between the measure of inner and outer circumference of the piston body envelope surface (inner circumference/outer circumference) is larger than 0, 5.
Thereby (the circumference of the engagement and disengagement device is relatively large in view of the piston force area) is achieved that the clamping surface can be made relatively short seen in the longitudinal direction still providing rigid engagement and thus the length of the piston body. This saves weight and space.
Suitably, the inner circumference measure of the piston body and the length measure (seen in the longitudinal direction) of the piston body define an area of a clamping surface of the piston body.
Preferably, the inner circumference measure of the piston body and the length measure (seen in the longitudinal direction) of the piston body define an area that is less than the area of a clamping surface of the piston body.
The definition of the measure of the inner circumference of the piston body envelope (inner) surface is the circumference of an imaginary circle, which has a diameter that corresponds with an inner diameter of the piston body (of a first and/or of a second and/or of a third piston body).
The definition of the measure of the outer circumference of the piston body envelope (outer) surface is the circumference of an imaginary circle, which has a diameter that corresponds with an outer diameter of the piston body (of a first and/or of a second and/or of a third piston body).
The hollow space preferably forms an expandable wall of the piston body, which expandable wall expands radially inward or outward when the hollow space is pressurized with a predetermined pressure.
The clamping surface of the piston body is thus arranged for clamping on the envelope surface of the adjacent telescoping element when the hollow space is pressurized with a predetermined pressure.
The hollow space and expandable wall (so called membrane) thus form the area of the clamping surface of the piston body. As the membrane of the piston body exhibits a large circumference (e.g.) diameter in view of the outer circumference of the piston body, the area of the clamping surface also will be relative large still if the length of the piston body is relative short in axial direction.
Thereby is achieved that the clamping area (contact area) and the transmissible axial force can be great even if the longitudinal length of the piston body is short.
Thereby is achieved that the cylinder housing is compact.
Thereby is achieved a lightweight and compact fluid actuator assembly which promotes the design of the telescoping element presenting low weight and compact feature.
Thereby is achieved an elongated telescopic device that suitably is used as a crane apparatus. The lightweight design is desired further out toward the crane tip.
Preferably, the fluid actuator assembly further comprises a second cylinder chamber, at least one of the first and second cylinder chamber is coupled to a fluid supply via a valve device.
Thereby there is achieved that a retraction of the piston body can be made by means of the fluid supply.
Suitably, the first fluid actuator assembly comprises a static clamping unit and/or at least one fluid actuator unit.
Preferably, the static clamping unit comprises a sleeve portion including a cavity (or at least two cavities), which cavity is coupled to a separate fluid supply or to a fluid supply coupled to the first and second cylinder chambers.
Suitably, the static clamping unit is activated by means of a control valve coupled to the fluid supply.
Preferably, the sleeve portion comprises an inner surface for contact with the outer envelope surface of the telescopic element and the cavity is arranged in the sleeve portion co-axially with the inner surface of the sleeve portion.
Suitably, the cavity forms a membrane comprising a flexible wall section formed between the cavity and the inner surface of the sleeve portion.
By the pressurizing of the cavity, there is achieved a stationary clamping force of the static clamping unit, which stationary clamping force holds the encompassed telescopic element in a braking state.
Suitably, the sleeve portion is provided with a standardized coupling entrance for enabling fluid communication between the fluid supply and the cavity of the sleeve portion.
Preferably, the cavity is formed by an inner sleeve and an outer sleeve.
Thereby is achieved a fluid actuator assembly comprising a static clamping unit for providing a static clamping with high force, whereby the fluid actuator assembly can be made in cost-effective production.
Suitably, the static clamping unit is activated by means of pressurized fluid fed by the fluid supply.
Preferably, the static clamping unit is activated by a separate fluid supply.
The telescoping elements can thus be rigidly positioned in extended state.
Preferably, the first fluid actuator assembly comprises the first and second piston bodies and a static clamping unit.
According to one aspect the elongated telescopic device is arranged as an arm member of a mobile drilling apparatus vehicle, which arm member carries a drilling and/or bolting equipment.
Thereby is achieved that the drilling apparatus vehicle can be designed less bulky, which is desirable in confined spaces.
According to a further aspect the elongated telescopic elements of the elongated telescopic device constitute crane boom sections or are arranged either inside or outside the crane boom sections.
Thereby is achieved that the telescopic elements can be used for providing the extraction/retraction of the crane boom sections as well as for constituting the crane boom per se.
Thereby is also achieved a less bulky mobile crane than prior art.
This is also achieved by a method for operating a telescopic device according to claim 11.
Thereby is achieved that the telescopic elements per se can be used as e.g. crane boom sections and that no additional actuators have to be mounted. Thereby is provided a telescopic device that is compact and energy saving.
Preferably, the first engagement and disengagement device comprises a clamping sleeve arranged for static clamping action around an envelope surface of an adjacent telescopic element.
Suitably, the adjacent (nestled) second telescopic element being slidable arranged in the enclosing first telescoping element, wherein the envelope surface of the second telescopic element is engaged or disengaged by the first fluid actuator assembly of the first telescoping element, is thus to be regarded to be used as a piston rod.
Preferably, a second bearing member (as a part of or as being comprised of the entire flexible clamping wall of the piston body or as a part of the entire surface of the fluid actuator assembly being in contact with the envelope surface of an adjacent telescopic element or as a portion thereof) is arranged between the fluid actuator assembly and the envelope surface of an adjacent telescoping element. The second bearing member comprises for example bronze alloy and/or tin bronze and/or lead free bronze and/or copper and/or aluminium-bronze and/or carbon graphite.
Suitably, a third bearing member is provided to the static clamping unit.
Preferably, the third bearing member comprises for example bronze alloy and/or tin bronze and/or lead free bronze and/or copper and/or aluminium-bronze and/or carbon graphite.
Suitably, the first engagement and disengagement device comprises a piston body arranged in a cylinder housing, wherein the piston body is designed for clamping action around an envelope surface of an adjacent telescopic element when any of the cylinder chambers of the cylinder housing being pressurized.
Preferably, the first pressure provided for the clamping action (engagement) being higher than the second pressure for the release (disengagement).
Suitably, the pressurizing of the first engagement and disengagement device with a second pressure for a release action involves that the first clamping sleeve or first piston body will release the clamping of the first engagement and disengagement device from the envelope surface of the adjacent (nestled) telescoping element.
Suitably, the pressurizing of the second engagement and disengagement device with a second pressure for a release action involves that the second clamping sleeve or second piston body will release the clamping of the second engagement and disengagement device from the envelope surface of the adjacent (nestled) telescoping element.
Preferably, the retraction of the first and second engagement and disengagement device (piston body) to a start position is performed by pressurizing the first engagement and disengagement device with a second pressure for release so that the piston body can be retracted in the cylinder housing to a start position.
Suitably, the pressurizing the engagement and disengagement device with a first pressure for clamping action and propelling the second engagement and disengagement device so as to provide said motion in said longitudinal direction.
Preferably, the fluid actuator assembly comprises a first engagement and disengagement device comprising a first piston body and comprises a second engagement and disengagement device comprising a second piston body.
Suitably, the piston rod engagement means comprises a pressure strengthening device, which is provided to strengthening the engagement of the first piston device to the piston rod arrangement.
Suitably, the fluid actuator assembly further comprises a third engagement and disengagement device comprising a clamping sleeve.
Preferably, the method further comprises the step of pressurizing the first and second engagement and disengagement device of the respective support element and the first telescopic element with a second pressure for release action of the first and second engagement and disengagement devices from the respective support element and the first telescopic element, so as to extend the telescopic device by means of kinetic energy.
Thereby is achieved an energy efficient operation of the telescopic device, by that the moved mass of the telescopic device is used for additional propulsion for extending the telescopic device.
There is thus provided a fast extension of the telescopic device as the engagement and disengagement device (actuators) are released and the propulsion is achieved by means of the kinetic energy and alternatively also by means of gravity.
Suitably, the method further comprises the step of lowering the telescopic device to a negative slope so as to make use of potential energy to extend the encompassed first and second telescopic element.
Thereby is provided an even more energy efficient operation of the telescopic device.
Suitably, the elongated telescopic device comprises fluid actuator assemblies using two or more cooperating fluid actuator units fixed to an interior portion of an outer telescoping element at the outer end thereof and coupled for engagement and disengagement to an outer portion of an inner telescoping element housed within and in contact with the outer telescoping element.
Preferably, the elongated telescopic device comprises at least one fluid actuator assembly using at least one fluid brake clamping unit for static holding and at least one fluid actuator unit fixed to an interior portion of an outer telescoping element at the outer end thereof and coupled for engagement and disengagement to an outer portion of an inner telescoping element housed within and in contact with the outer telescoping element.
Suitably, the piston rod engagement and disengagement device comprises a pressure strengthening device, which is provided to strengthening the engagement of the first piston device to the adjacent telescopic element outer envelope surface.
Preferably, each standardized piston body comprises an expandable hollow space provided for fluid communication with a cylinder chamber of a standardized cylinder housing enclosing the standardized piston body.
Suitably, by pressurization of the hollow space to a certain degree there is provided a clamping action of the standardized piston body to an envelope surface of an inside positioned telescoping element at the same time as the standardized piston body is propelled within the standardized cylinder housing by means of the pressurized cylinder chamber (being in fluid communication with the hollow space thus also being pressurized) which implies that the inside positioned telescoping element will be propelled relative the standardized cylinder housing fixed to the interior of an outer telescoping element enclosing the inside positioned telescoping element.
Preferably, the elongated telescopic device comprises a support element formed to partly or entirely encompass (nestled) first and second telescopic element mounted so as to be telescopically slidable relative each other in a longitudinal direction; the support element comprises a support element fluid actuator assembly; the first telescopic element is arranged to encompass the second telescopic element and comprises a first fluid actuator assembly; the support element fluid actuator assembly is fixed to an interior portion of the support element and is arranged for engagement or disengagement to a first envelope surface of the first telescopic element; or the support element fluid actuator assembly is fixed to a first outer portion of the first telescopic element and is arranged for engagement or disengagement to an interior surface of the support element, the first fluid actuator assembly is fixed to a first interior portion of the first telescopic element and is arranged for engagement or disengagement to a second envelope surface of the second telescopic element; or the first fluid actuator assembly is fixed to a second outer portion of the second telescopic element and is arranged for engagement or disengagement to a first interior surface of the first telescopic element.
The present invention will now be described by way of examples with references to the accompanying schematic drawings, of which:
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, wherein for the sake of clarity and understanding of the invention some details of no importance may be deleted from the drawings.
For saving energy, all the fluid actuator units are disengaged from the respective telescopic element, wherein the kinetic energy provides further extraction motion of the telescopic elements 9. The same procedure may be used for retraction.
The elongated telescopic device comprising the telescopic elements and fluid actuator assemblies may according to different aspects be adapted to one or several of following industrial segments; construction industry, jacking systems for oil well drilling and service platforms, agricultural equipment industry, marine industry, crane manufacture industry and other industrial segments.
The present invention is of course not in any way restricted to the preferred embodiments described above, but many possibilities to modifications, or combinations of the described embodiments, thereof should be apparent to a person with ordinary skill in the art without departing from the basic idea of the invention as defined in the appended claims.
One aspect may involve that the telescopic device is adapted for momentary disengaging all pistons from the encompassed adjacent encompassed (nestled) telescopic element for propelling the mass of the telescopic elements using the kinetic energy of the mass (in a way reminding of a freewheel clutch). One aspect may involve that a static clamping unit may clamp (hold) rigidly to the entire circumference of the envelope surface of the telescopic element being in contact with the inner surface (clamping surface) of the static clamping unit. One aspect may involve that a clamping surface of a piston of a fluid actuator exhibits larger area than that of a piston force area of the piston. The clamping surface of the static clamping unit, seen in the axial direction, has an extension that is longer than the length of a clamping surface of a piston of a fluid actuator, seen in the axial direction. The fluid may be gas or hydraulic oil.
Filing Document | Filing Date | Country | Kind |
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PCT/SE2015/051228 | 11/16/2015 | WO | 00 |