Hydraulic torque wrench system comprising an operator handle

Abstract

A hydraulic torque wrench system is provided (1) comprising: a pump unit (2); a tool head (4) arranged to be connected to a threaded fastener; a hydraulic conduit (12) arranged between the pump unit (2) and the tool head (4); a control unit (3) configured to control the pump unit (2) to cycle for performing a tightening operation; and an operator handle (6) arranged to communicate with the control unit (3), the operator handle (6) comprising: an indicator device (9a, 9b) arranged to indicate to an operator a status of the tightening operation as communicated by the control unit (3), and a trigger device (8a, 8b) configured to, upon activation by the operator, enable the control unit (3) to start a tightening operation. The operator handle (6) is arranged on the hydraulic conduit (12) such that the operator can hold the operator handle (6) and the tool head (4) simultaneously.

Description

[0001]HYDRAULIC TORQUE WRENCH SYSTEM COMPRISING AN OPERATOR HANDLEField of the inventionThe present invention relates to the field of hydraulic torque wrench system.Background of the invention Hydraulic torque wrench systems are typically used for high torque applications with large bolts e.g. in wind towers and to join flanges in the oil and gas industry.Such systems comprise a tool head (wrench) coupled via hoses to a hydraulicpump. In the tool head, a piston is arranged in a cylinder to alternatingly advance and retract by the application of hydraulic pressure from the pump on either side of the piston. The piston is in turn mechanically connected to a pawl and ratchet mechanism that translates the advancing movement of the piston to a rotating movement of an output interface (such as a square or socket) of the tool head, whereby the fastener is tightened. The pawl and ratchet mechanism is further arranged to refrain from translating the retracting movement of thepiston to the output interface. Some more sophisticated hydraulic torque wrenchsystems are configured to be able to auto-cycle, which means that the operator will only have to start the tightening operation, then the control unit automatically controls cycling of the pump to alternatingly advance / retract thepiston. Alternatively, the system may be operated in manual mode, which meansthat operator must manually initiate each cycle of the tightening.Hydraulic torque wrench systems typically comprise a control pendant (aremote control) connected via a cable to the control unit, the latter typicallybeing situated at the pump. The control pendant is used by the operator tocontrol the tightening operation, such as entering the target torque value and tostart / stop the tightening operation. Tightening operations with such systems may sometimes be performed by asingle operator. Mounting the tool head to the fastener, which is typically locatedat least a few meters away from the pump unit, may be cumbersome for the operator since he / she may typically want to also bring the control pendant tothe fastener to be able to start the tightening operation right after the tool headhas been mounted to the fastener. This may result in that the operator needs tohold the control pendant under the arm while using both hands to mount the(relatively heavy) tool head to the fastener, which is a less ergonomic workingposition. In other situations, the tightening operations are performed by two operators.Typically, one operator mounts the tool head to the fastener while the other onehandles the control pendant to start / stop the tightening operation. A hazardoussituation may arise if the operator handling the control pendant happens to start the tightening operation before the other operator has removed his / her handsfrom the tool head / work piece, who thereby risk hand crush injuries. Thecommunication between the operators may be difficult due to the often noisyenvironment at the work spot, which increases the risk of such accidents to happen.Some safety products have been developed for the purpose of reducing theabove-mentioned risks. However, further improvements in the field would bedesired. Summary of the invention It would be advantageous to achieve a hydraulic torque wrench systemovercoming, or at least alleviating, the above-mentioned drawbacks. Inparticular, it would be desirable to enable a more ergonomic hydraulic torquewrench system that is safer to use.To better address one or more of these concerns, a hydraulic torque wrenchsystem having the features defined in the independent claim is provided.Preferable embodiments are defined in the dependent claims.Hence, according to an aspect, a hydraulic torque wrench system is provided.The hydraulic torque wrench system comprises: a pump unit; a tool head having an output interface arranged to be connected to a threaded fastener; a hydraulicconduit arranged to hydraulically connect the pump unit with the tool head; acontrol unit configured to control the pump unit to cycle for performing a tightening operation; and an operator handle arranged to communicate with the control unit. The operator handle comprises an indicator device arranged to indicate to an operator a status of the tightening operation as communicated by the control unit, and a trigger device configured to, upon activation by the operator, enable the control unit to start a tightening operation. Further, the operator handle is arranged on the hydraulic conduit such that the operator can hold the operator handle and the tool head simultaneously.With the present aspect, the operator handling the tool head (includingmounting it to a fastener) will have control of when the tightening can start. This means that he / she can make sure to remove his / her hands from potentiallyhazardous areas around the tool head / work piece, before activating enablementof start of the cycling of the pump unit.Since the operator handle is mounted on the hydraulic conduit within reachfrom the tool head, the operator need not bring any control pendant withhim / her to the fastener but can enable start of the tightening operation by activating the trigger device of the operator control handle. For example, the operator may carry the tool head by holding directly in the tool head with in onehand and the operator handle in the other. The operator handle will further aidin holding the tool head in a desired position. Since the operator handle is arranged on the hydraulic conduit, any cabling arranged to provide wired communication between the operator handle and the control unit (the latter typically being located remote from the tool head) can bearranged along the hydraulic conduit, such as attached to, or integrated with, thehydraulic conduit. Hence, a more ergonomic handling is provided since the cabling is more out of the way for the operator and the risk of tangling is reduced. Since the trigger device communicates electronically (by wire or wirelessly) with the control unit, the operator handle can be made relatively small in size and less mechanically complex as compared to if the tightening operation isenabled / disabled hydraulically by means of circuits and valves inside thehandle.Since the operator handle comprises an indicator device for indicating the statusof the tightening and is close / next to the tool head, the operator may givehis / her full attention to the area around the tool head. Hence, the operator neednot turn his / her head towards the pump unit / control unit to see the status ofthe tightening. Looking away from the area around the tool head may increasethe risk of hand crush injuries as the tool head may move and potentiallysqueeze the hand as the operator has his / her attention focused in anotherdirection. Hence, with the present aspect, the operator has all he / she needs (start trigger and status indicator) to perform the tightening operation in one spot, close tothe tool head, which improves both ergonomics and safety.In conclusion, a more ergonomic and safer handling of the hydraulic torque wrench system is provided. The operator handle may be arranged on the hydraulic conduit so close to the tool head that the operator can hold the operator handle with one hand and the tool head with the other hand. For example, the part of the hydraulic conduit interconnecting the operator handle and the tool head may be so short that, when stretched, the operator handle is less than a meter, such as less than half ameter, such as less than 20 cm from the tool head. The operator handle may evenbe mounted to the hydraulic conduit just adjacent to the tool head. In otherwords, a length of a part of the hydraulic conduit interconnecting the operatorhandle and the tool head may be less than one meter. This facilitates operatorhandling. In the present specification, the term “hydraulic conduit” may include a two-wayarrangement, such as two channels (such as hoses), for allowing hydraulic fluidto flow simultaneously in opposite directions (to / from the pump). Such channelsmay e.g. be arranged in parallel, beside each other or coaxially (one inside the other). The indicator device may be integrated in the (housing of the) operator handle. The trigger device may be integrated in the (housing of the) operator handle.According to an embodiment, the operator handle may be rotatably arranged onthe hydraulic conduit with a rotation axis extending along the longitudinaldirection of the hydraulic conduit. This further facilitates handling of the systemfor the operator and improves the ergonomics. According to an embodiment, the operator handle may be clamped on to a hoseof the hydraulic conduit. Hence, the operator handle may not have any hydrauliccircuit in itself but may just be clamped on to the hose(es) interconnecting the tool head and the pump unit.Alternatively, the operator handle may further comprise a first hydraulicconnection interface arranged to be connected to a hose extending from the pump unit, a second hydraulic connection interface arranged to be connectedeither directly, or via a hose, to the tool head, and an internal hydraulic conduitextending inside the operator handle and interconnecting the first and secondhydraulic connection interfaces. Thereby, the operator handle can be coupled tothe end of the hose leading to the pump unit as well as to the tool head (directly or indirectly).For example, the first and second hydraulic connections may be quick couplings.For example, the internal hydraulic conduit may be fluid channels machinedinside the operator handle. According to an embodiment, the torque wrench system may further comprise an additional handle (separate from the operator handle) extending out from thetool head. The additional handle may further facilitate handling of the tool headfor the operator and make it more ergonomic. Further, as the operator holds the two handles his / her hands are kept away from dangerous positions at the tool head / fastener / workpiece interfaces, which improves the safety. According to an embodiment, the additional handle extends out from the tool head in a longitudinal direction different from that of the extension of the operator handle, such as by an offset angle comprised within the range of 90 to180 degrees. Alternatively, the additional handle may extend in a directionparallel with (but spaced apart from) the longitudinal direction of the operator handle.According to an embodiment, the status of the tightening operation that theindicator device is arranged to indicate comprises one or more of the following:an indication that a tightening operation has started, an indication that atightening operation has ended, an indication if a just performed tighteningoperation was okay (OK) or not okay (NOK), an indication of a progression of thetightening, and an indication that an error has occurred. By having provided thisinformation about the tightening at the operator handle, close to the tool head, the operator can bring his / her full attention to the area around the fastener / tool head, which improves the safety.For example, the indicator device may comprise one or more LEDs to indicatethe status.According to an embodiment, the trigger device may comprise two triggers thathave to be activated simultaneously or in a predetermined sequence for causingthe trigger device to enable the control unit to start a tightening operation. Thisreduces the risk that something or someone accidentally pushes one trigger and thereby enables start of a tightening operation. Hence, the safety is improved. Further, if the triggers have to be activated in a predetermined sequence, that reduces the risk of accidental start if the operator grabs the handle and unintentionally activates both triggers simultaneously. For example, the predetermined sequence may comprise that the triggers mayhave to be pressed / released within predetermined time ranges with respect toeach other. For example, a first one of the triggers may have to be pressed and then released, then, within a predetermined time limit from the release of the first trigger, a second one of the triggers may have to be pressed in order toenable the control unit to start a tightening operation. According to anotherexample, the first trigger may have to be continuously pressed and then, inresponse to the second trigger also being pressed (simultaneously with the firstone), the control unit may command the pump unit to start cycling. Such sequence may e.g. be used when manually cycling the tightening operation. Other sequences may also be envisaged.According to an embodiment, the two triggers may be arranged on (radially)opposite sides of the operator handle, and preferably spaced apart as seen in thelongitudinal direction of the handle. Such placement of the triggers may furtherreduce the risk that something or someone accidentally pushes the triggers in away that enables start of a tightening operation.According to an embodiment, the control unit may be configured to operate thesystem in a first operation mode (which e.g. may be referred to as a one manoperation mode), in which the activation of the trigger device (in itself) triggersthe control unit to start the tightening operation, and / or in a second operationmode (which e.g. may be referred to as a two man operation mode), in which theactivation of the trigger device enables the control unit to start the tighteningoperation only upon trigger of a further actuator arranged separately from theoperator handle (such as at the pump unit or in a pendant coupled to the control unit). The first operation mode may typically be used when the system is to be operated by a single operator. The operator may first enter parameters of the tightening at the control unit / control pendant and then bring the tool head (and the operator handle) to the fastener, and when properly mounted, he / she may start the operation by simply activating the triggering device. The second operation mode may typically be used when the system is to be operated by two operators. A first operator may handle the control unit / control pendant while a second operator brings the tool head (and the operator handle) to the fastener, and when properly mounted, the second operator may activate the triggering device, which signals to the control unit that a tighteningoperation can be started. The first operator may then trigger / activate theadditional actuator (e.g. a button at the control pendant or at the pump unit), whereupon the tightening operation starts. Brief description of the drawingsThis and other aspects will now be described in more detail in the followingillustrative and non-limiting detailed description of embodiments, withreference to the appended drawings.Figure 1 shows a hydraulic torque wrench system according to an embodiment.Figure 2 shows an operator handle of a hydraulic torque wrench systemaccording to an embodiment All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the embodiments, wherein otherparts may be omitted. Like reference numerals refer to like elements throughoutthe description. Detailed description of embodimentsA hydraulic torque wrench system 1 according to an embodiment will bedescribed with reference to Figure 1. The hydraulic torque wrench system 1 (in the following referred to as “thesystem”) comprises a pump unit 2, a tool head 4 (which alternatively may bereferred to simply as a wrench or tool), a control unit 3 and an operator handle 6. Optionally, the system 1 may further comprise a control pendant 10. The tool head 4 may comprise an output interface 5, such as a hex or square, adapted to be mounted to a (threaded) fastener such as a bolt, screw or nut.Inside the tool head 4, a piston (not shown) may be arranged to, by means ofhydraulic pressure, reciprocate to drive a pawl and ratchet mechanism (alsoarranged inside the tool head 4), which in turn drives the output interface 5 for turning the fastener. The tool head 4 may be hydraulically connected to the pump unit 2 via a hydraulic conduit 12. The hydraulic conduit 12 may e.g. comprise one or more hoses. Such hoses may be arranged in parallel, beside each other, or asillustrated in Figure 1, coaxially, one inside the other.The pump unit 2 may be arranged to provide the hydraulic pressure for reciprocating the piston in the tool head 4. The pump unit 2 may e.g. be a multi or single stage pump. The control unit 3 of the system 1 may be arranged remote from the tool head 4, such as in / at the pump unit 2 (as illustrated in Figure 1) and / or in the control pendant 10. The control unit 3 may comprise a memory and processing means. The control unit 3 may be provided in a single device or distributed in several devices. The control unit 3 may be configured to control the pump unit 2 to cycle (i.e. to provide said hydraulic pressure) for performing a tightening operationwith the tool head 4. The cycling may be automatic (which may be referred to asauto-cycling) or manual. The control pendant 10 may comprise a user interface, such as a touch display, for allowing entering user input to the system 1. The control pendant 10 may be configured to indicate e.g. a status of the tightening and results from the tightening. The control pendant 10 may be arranged to communicate (via a wire or wirelessly) with the control unit 3.The operator handle 6 is arranged to communicate with the control unit 3, suchas wirelessly or via a cable (not shown). Such cable may preferably be drawnalong the hydraulic conduit 12 to the control unit 3 in the pump unit 2 to reducethe risk of tangle. The operator handle 6 comprises an indicator device 9a, 9b arranged to indicate,to an operator holding the handle 6, a status of the tightening operation ascommunicated by the control unit 3. For example, the indicator device 9a, 9bmay comprise one or more LEDs 9a, 9b that may be lit in different colours and / or sequences to signal different statuses. The indicator device 9a, 9b maye.g. be configured to indicate: that a tightening operation has started / ended, if a just performed tightening operation was okey (OK) or not okay (NOK), aprogression of the tightening, and / or that some kind of error has occurred.The operator handle 6 further comprises a trigger device 8a, 8b. The triggerdevice 8a, 8b is configured to, upon activation by the operator, enable the controlunit to start a tightening operation. This may include that activation of the trigger device 8a, 8b commands the control unit 3 to start the tightening operation (no further input required) and / or that activation of the trigger device 8a, 8b signals to the control unit 3 that a tightening can be started if triggered bya further actuator (e.g. provided at the control pendant 10).For example, the control unit 3 may be configured to operate the system 1 in a first (one man) operation mode, in which the activation of the trigger device 8a, 8b triggers the control unit 3 to start the tightening operation (without requiringany further input), and / or in a second (two man) operation mode, in which theactivation of the trigger device 8a, 8b enables the control unit 3 to start the tightening operation only upon trigger of a further actuator arranged separatelyfrom the operator handle 6 (such as at the control pendant 10).The trigger device 8a, 8b may comprise two triggers 8a, 8b, preferably arranged in a way that reduces the risk of them by accident being pressed simultaneously as an operator grabs the handle 6. For example, one trigger 8a may be arranged in a front half of the handle 6 and the other one 8b in a rear half of the handle 6(as seen in a longitudinal direction of the handle 6), as illustrated in Figure 1.The triggers 8a, 8b may e.g. be arranged on radially opposite sides of the handle6 as illustrated in Figure 1 (i.e. one trigger 8a on the upper half and the other one8b on the lower half of the handle 6).The control unit 3 may be configured to only initiate cycling the pump unit 2 in case the two triggers 8a, 8b are actuated simultaneously and / or according to at least one predetermined sequence. The sequence may e.g. look different in casethe system 1 is operated in a manual or automatic mode. Such sequence maypreferably be adapted so as to reduce the risk of accidental start of a tightening. For example, the triggers 8a, 8b may have to be actuated in a certain order and / or within a predetermined time window.The operator handle 6 is arranged on the hydraulic conduit 12 such that theoperator can hold the operator handle 6 and the tool head 4 simultaneously (e.g.with one hand holding the tool head 4 and the other one holding the operator handle 6). Hence, the operator handle 6 may be arranged close to the tool head4, preferably just adjacent to the tool head 4 as illustrated in Figure 1. Preferably,the operator handle 6 may be arranged on the hydraulic conduit 12 such that theoperator can use the handle 6 to carry / mount the tool head 4 to the fastener.The operator handle 6 may e.g. be rotatably arranged on the hydraulic conduit 12 such that the operator can rotate the handle 6 around the hydraulic conduit 12 and its’ own longitudinal axis. The operator handle 6 may comprise a first hydraulic connection interface 13(such as a quick coupling) arranged to be connected to the hose extending fromthe pump unit 2, and a second hydraulic connection interface 14 arranged to beconnected either directly, or via a (preferably relatively short) hose, to the toolhead 4. Further, channels (not shown) may be arranged inside the operatorhandle 6 so as to interconnect the first and second hydraulic connectioninterfaces 13, 14. Hence, these channels may constitute the part of the hydraulicconduit 12 may extending through the handle 6.Alternatively, as schematically illustrated in Figure 2, the operator handle 26may be clamped on to the outside of a hose of the hydraulic conduit 12.Turning again to Figure 1, an additional handle 11 may optionally be arrangedon the tool head 4 so as to provide a more ergonomic gripping of the tool head 4for the operator. The extra handle 11 may be arranged to extend out from the tool head 4 such that the operator can grab one handle 6, 11 with each hand.In the following, an example of operation of the system 1 by a single operatorwill be described. The operator may first set the control unit in the first (one man) operation mode and enter any required parameters of the tightening, such as a target torqueand / or selecting a tightening program. This may e.g. be done by means of thecontrol pendant 10. The operator may then put away the control pendant 10 (e.g. hanging it on a dedicated spot) and go and mount the tool head 4 to thefastener, e.g. by carrying the tool head 4 by means of the operator handle 6 andthe additional handle 11. As the tool head 4 is properly mounted and theoperator has made sure his / her hands are removed from any dangerous areas,the operator may actuate the trigger device 8a, 8b (e.g. by pressing the triggers 8a, 8b according to any required sequence), whereupon the operator handle 6 sends a signal to the control unit 3 to start cycling the pump unit 2, therebystarting the tightening. While the tightening proceeds, the operator may havehis / her full attention on the area around the tool head 4 and fastener as he / shecan see the status of the tightening at the indicator device 9a, 9b at the operator handle 6 located just nearby the tool head 4 / fastener. As the indicator device 9a, 9b indicates that the tightening is ready / OK, the operator may remove the tool head 4 from the fastener and proceed to the next joint.In the following, an example of operation of the system 1 by two operators willbe described. A first one of the operators may set the control unit in the second (two man) operation mode and enter any required parameters of the tightening, such as a target torque and / or selecting a tightening program (e.g. be by means of the control pendant 10). In the meantime, the other (second) operator may go andmount the tool head 4 to the fastener (e.g. by carrying the tool head 4 by meansof the operator handle 6 and the additional handle 11). As the tool head 4 isproperly mounted and the second operator has made sure his / her hands areremoved from any dangerous areas, the second operator may actuate the trigger device 8a, 8b (e.g. by pressing the triggers 8a, 8b according to any required sequence), whereupon the operator handle 6 sends a signal to the control unit 3 indicating that a tightening can be started. The control unit 3 then awaits the first operator to actuate the additional actuator (e.g. on the control pendant 10), whereupon the control unit 3 commands the pump unit 2 to start cycling. It will be appreciated that the trigger device 8a, 8b of the operator handle 6 and the additional actuator (at the control pendant 10) alternatively may have to be actuated in the opposite order to start the tightening operation. While thetightening proceeds, the second operator may have his / her full attention on thearea around the tool head 4 and fastener as he / she can see the status of the tightening at the indicator device 9a, 9b at the operator handle 6 located just nearby the tool head 4 / fastener. As the indicator device 9a, 9b indicates that the tightening is ready / OK, the second operator may remove the tool head 4 from the fastener and proceed to the next joint. The person skilled in the art realizes that the present invention by no means is limited to the embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article"a" or "an" does not exclude a plurality. The mere fact that certain measures arerecited in mutually different dependent claims does not indicate that acombination of these measures cannot be used to advantage.

Claims

CLAIMS1. Hydraulic torque wrench system (1) comprising:a pump unit (2);a tool head (4) having an output interface (4) arranged to beconnected to a threaded fastener; ahydraulic conduit (12) arranged to hydraulically connect thepump unit (2) with the tool head (4);a control unit (3) configured to control the pump unit (2) to cyclefor performing a tightening operation; and an operator handle (6) arranged to communicate with the control unit (3), the operator handle (6) comprising:- an indicator device (9a, 9b) arranged to indicate to an operator astatus of the tightening operation as communicated by the control unit (3), and -a trigger device (8a, 8b) configured to, upon activation by theoperator, enable the control unit (3) to start a tightening operation,wherein the operator handle (6) is arranged on the hydraulicconduit (12) such that the operator can hold the operator handle (6) andthe tool head (4) simultaneously.

2. Hydraulic torque wrench system (1) according to claim 1, wherein theoperator handle (6) is rotatably arranged on the hydraulic conduit (12)with a rotation axis extending along the longitudinal direction of the hydraulic conduit (12).

3. Hydraulic torque wrench system (1) according to claim 1 or 2, whereinthe operator handle (6) is clamped on to a hose of the hydraulic conduit(12).

4. Hydraulic torque wrench system (1) according to claim 1 or 2, whereinthe operator handle (6) further comprises:a first hydraulic connection interface (13) arranged to beconnected to a hose extending from the pump unit (2),a second hydraulic connection interface (14) arranged to beconnected either directly, or via a hose, to the tool head (4), andan internal hydraulic conduit extending inside the operator handle(6) and interconnecting the first and second hydraulic connectioninterfaces (13, 14).

5. Hydraulic torque wrench system (1) according to any one of thepreceding claims, further comprising an additional handle (11) extendingout from the tool head (4).

6. Hydraulic torque wrench system according to claim 5, wherein theadditional handle (11) extends out from the tool head (4) in alongitudinal direction different from that of the extension of the operator handle (6), such as by an offset angle comprised within the range of 90 to180 degrees.

7. Hydraulic torque wrench system (1) according to any one of thepreceding claims, wherein said status of the tightening operation that the indicator device (9a, 9b) is arranged to indicate comprises one or more ofthe following: an indication that a tightening operation has started, an indication that a tightening operation has ended, an indication if a just performed tightening operation was okey (OK) or not okay (NOK), an indication of a progression of the tightening, andan indication that an error has occurred.

8. Hydraulic torque wrench system (1) according to any one of thepreceding claims, wherein the trigger device (8a, 8b) comprises twotriggers (8a, 8b) that have to be activated simultaneously or in apredetermined sequence for causing the trigger device (8a, 8b) to enablethe control unit (3) to start a tightening operation.

9. Hydraulic torque wrench system (1) according to claim 8, wherein thetwo triggers (8a, 8b) are arranged on opposite sides of the operatorhandle (6).

10. Hydraulic torque wrench system (1) according to any one of thepreceding claims, wherein the control unit (3) is configured to operate the system (1) in:a first operation mode, in which the activation of the trigger device (8a, 8b) triggers the control unit (3) to start the tightening operation,and / or asecond operation mode, in which the activation of the triggerdevice (8a, 8b) enables the control unit (3) to start the tighteningoperation only upon trigger of a further actuator arranged separatelyfrom the operator handle (6).

11. Hydraulic torque wrench system (1) according to any one of thepreceding claims, wherein a length of a part of the hydraulic conduit (12) interconnecting the operator handle (6) and the tool head (4) is less than one meter.

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