Socket for power tool, method of controlling power tool, control system, and power tool

Abstract

To provide an improved socket for a power tool.SOLUTION: A socket (28) for a power tool (10) is arranged to rotate about a socket axis (32) and comprises: a cylindrical section (82) having an end surface (86) and a plurality of engaging surfaces (88) arranged parallel with the socket axis on the internal side of the cylindrical section; an inner section (84) positioned radially inside the cylindrical section with respect to the socket axis and having a stopping surface (90) offset from the end surface such that the engaging surfaces are positioned between the stopping surface and the end surface; and a socket opening (30) extending radially with respect to the socket axis through the cylindrical section and the inner section. The cylindrical section (82) comprises at least one internal slope (126) extending away from the stopping surface on the internal side of the cylindrical section. A method, a control system (40), and a power tool (10) are also provided.SELECTED DRAWING: Figure 8a

Description

[Technical field]

[0001] The present disclosure relates generally to power tools, and more particularly to a power tool socket including at least one internal bevel, a method for controlling a power tool including such a socket, a control system for controlling a power tool including such a socket, a method for controlling a power tool including a check operation, a control system for controlling a power tool to perform a check operation, and a power tool. [Background technology]

[0002] An open end power tool may include a socket rotatable about a socket axis and having a socket opening for receiving a bolt or shaft radially relative to the socket axis. For example, when a bolt encircling a shaft is to be threaded into a coupling on the shaft, the socket is positioned in an open position and the power tool is moved relative to the shaft to radially receive the shaft through the socket opening. The power tool and / or bolt is then moved axially along the shaft until the bolt is received in the socket. The bolt can then be tightened into the coupling using the power tool.

[0003] Some prior art power tools require the operator to release the actuating element after each tightening operation, lift the power tool off the bolt, press and hold the actuating element again to control the socket back to the open position, and remove the power tool from the shaft. In such power tools, the actuating element may rotate the socket in alternating directions each time it is actuated. Summary of the Invention [Problem to be solved by the invention]

[0004] One object of the present disclosure is to provide an improved socket for a power tool.

[0005] It is a further object of the present disclosure to provide a socket for a power tool that speeds positioning of the socket in the open position.

[0006] It is a further object of the present disclosure to provide a socket for a power tool that facilitates removal of the power tool after the joint has been tightened.

[0007] It is a further object of the present disclosure to provide a socket for a power tool that addresses some or all of the above-mentioned objects in combination.

[0008] It is a further object of the present disclosure to provide a method for controlling a power tool that addresses one, some or all of the above-mentioned objects.

[0009] It is yet another object of the present disclosure to provide a control system for controlling a power tool that addresses one, some or all of the above-mentioned objects.

[0010] It is yet another object of the present disclosure to provide a power tool that overcomes one, some or all of the above-mentioned objects. [Means for solving the problem]

[0011] According to a first aspect, there is provided a socket for a power tool arranged to rotate about a socket axis, the socket comprising: a cylindrical portion having an end face and a plurality of engagement surfaces parallel to the socket axis inside the cylindrical portion; an inner portion having a stop surface located radially inward of the cylindrical portion relative to the socket axis and offset from the end face, the engagement surface being located between the stop surface and the end face; and a socket opening extending radially relative to the socket axis and through the cylindrical portion and the inner portion, the cylindrical portion including at least one internal bevel extending away from the stop surface inside the cylindrical portion.

[0012] The socket includes a socket opening and is therefore an open-ended socket. A power tool that includes a socket may be referred to as an open-ended power tool.

[0013] During the tightening operation of the joint, the engagement surfaces can be engaged with the engageable surfaces of the bolt and the socket can be rotated in a tightening direction. Once the tightening operation is completed, the socket can be rotated in a release direction opposite the tightening direction. The socket can be rotated in the release direction, for example automatically immediately after the tightening operation is completed. As the socket rotates in the release direction, each internal bevel engages a corner between the engageable surfaces on the bolt. This causes the socket to move away from the bolt along the socket axis, while the corner moves along the internal bevel until the socket falls off the bolt. Thus, by rotating the socket in the release direction, the socket can be quickly and easily separated from the tightened joint.

[0014] Once the socket is separated from the joint, it can continue to rotate in the release direction to an open position where the socket opening is aligned with the base opening of the base element. This allows the socket to be quickly and easily positioned in the open position. The socket can be automatically positioned in the open position immediately after completion of the tightening operation. Thus, the operator does not need to lift the power tool off the bolt and run a separate positioning program to position the socket in the open position.

[0015] The socket can be configured to tighten the bolt in a conventional manner by rotating in a tightening direction. The power tool can be of any type that includes a socket having at least one internal bevel as described herein.

[0016] The cylindrical portion does not completely surround the socket axis as a result of the socket opening, which may extend entirely through the socket in a direction parallel to the socket axis.

[0017] The engagement surface can be located along a direction parallel to the socket axis between the stop surface and the end surface. The engagement surface can be configured to engage an engageable surface of a bolt to be tightened. The cylindrical portion can include at least four engagement surfaces, such as six engagement surfaces.

[0018] The inner side is the side facing the socket axis. At least one internal bevel can be located between the end face and the stop face when viewed in a plane transverse to the socket axis. Each internal bevel can extend from the stop face. Each of the end face and the stop face can be flat and perpendicular to the socket axis.

[0019] The at least one internal bevel can include a plurality of internal bevels. One internal bevel can be associated with each of the at least four engagement surfaces. Thus, the socket can include at least four internal bevels.

[0020] Each internal bevel can be straight. Alternatively or additionally, each internal bevel can extend from the stop surface to the end surface.

[0021] The cylindrical portion may include a circular drive profile on an exterior side of the cylindrical portion, concentric with the socket axis and drivingly engaged by the wheel. The exterior side is the side facing away from the socket axis. The drive profile may include teeth or a friction surface.

[0022] According to a second aspect, there is provided a method for controlling a power tool for tightening a joint, the power tool comprising a base element having a base opening, a socket according to the first aspect, a motor arranged to drive the socket, and a control system configured to control the motor, the socket being rotatable about a socket axis from an open position in which the socket opening is aligned with the base opening, the method comprising: the control system instructing the socket to perform a tightening operation to tighten the joint; and the control system instructing the socket to perform a release operation after the tightening operation has been performed.

[0023] The release operation may be performed automatically immediately after the tightening operation is finished. Thus, the method may initiate the release operation immediately after the tightening operation is completed, instead of performing the release operation as a separate operation, for example in response to a command from an operator. Alternatively, the release operation may be initiated by an operator activating an actuating element of the power tool, for example.

[0024] During a clamping operation, the socket rotates about the socket axis in a clamping direction. The clamping operation may be considered complete when a target torque is applied to the joint. The release operation involves rotating the socket about the socket axis in a release direction opposite the clamping direction.

[0025] According to a third aspect, there is provided a control system for controlling a power tool for tightening a joint, the control system comprising: a base element having a base opening, a socket according to the first aspect, a motor arranged to drive the socket, and a control system configured to control the motor, the socket being rotatable about a socket axis from an open position in which the socket opening is aligned with the base opening, the control system comprising at least one data processing device and at least one memory storing at least one computer program, the at least one computer program including program code which, when executed by the at least one data processing device, causes the at least one data processing device to perform the steps of instructing the socket to perform a tightening operation to tighten the joint, and instructing the socket to perform a release operation after the tightening operation has been performed.

[0026] According to a fourth aspect, there is provided a method for controlling a power tool for tightening a joint, the power tool comprising: a base element having a base opening; a socket having a socket opening; a motor arranged to drive the socket; and a control system configured to control the motor, the socket being rotatable about a socket axis from an open position in which the socket opening is aligned with the base opening, the method including: the control system instructing the socket to perform a tightening operation to tighten the joint; the control system instructing the socket to perform a check operation after performing the tightening operation; the control system monitoring a response of at least one parameter associated with the socket to the check operation; the control system determining based on the response whether the socket is engaged with the joint; and when the control system determines that the socket is not engaged with the joint, instructing the socket to be positioned in the open position.

[0027] The check operation can be performed automatically immediately after completion of the tightening operation. The socket can be automatically placed in the open position as soon as it is determined that the socket is not engaged with the joint. Thus, instead of lifting the power tool from the joint and manually commanding the socket to move to the open position, the operator can simply move the power tool away from the joint. This method automatically concludes that the socket is released from the bolt and automatically rotates the socket to the open position. The speed of rotation of the socket can be increased upon determining that the socket is not engaged with the joint.

[0028] By evaluating the response to the check operation, it is possible to automatically detect when the socket has separated from the joint. Thus, in this manner, the clamping operation and positioning of the socket to the open position can be performed in a single sequence. In this manner, the socket can automatically return to the open position after the clamping operation. In some applications, this method allows a time saving of approximately one second per clamping cycle.

[0029] Determining whether the socket is engaged in the joint can be done in a variety of ways, according to one example, it is concluded that the socket is free to rotate when it rotates beyond a threshold angular distance, such as 20 degrees to 30 degrees, about the socket axis.

[0030] The check operation involves rotating or commanding the socket to rotate about the socket axis in either a tightening or loosening direction. However, if the socket is not separated from the joint, the socket should only exert a relatively small torque so that the tightening torque of the joint achieved by the tightening operation is not changed. That is, the check operation should not cause further tightening or loosening of the joint.

[0031] The power tool may include a socket according to the first aspect, in which case the checking action may include a release action according to the second or third aspect, the release action disengaging the power tool from the joint and may be used to determine when this separation has occurred, or the power tool may include a socket that does not include an internal bevel.

[0032] The checking operations may include controlling the socket based on rotational position, rotational speed, rotational acceleration, torque and / or current.

[0033] The checking operation may include controlling the socket based on a torque that is less than a maximum torque during the tightening operation. The maximum torque during the checking operation may be less than 30%, such as less than 20% of the maximum torque during the tightening operation.

[0034] The checking operation may include controlling the socket based on a current that is less than a maximum current during the tightening operation.

[0035] The socket may be commanded to perform the check operation in pulses. The socket may be controlled based on a relatively large torque during the pulses and a relatively small, zero or negative torque between the pulses. Additionally or alternatively, the socket may be controlled based on a relatively large current during the pulses and a relatively small, zero or negative current between the pulses. In either case, the pulses may have a frequency of at least 5 Hz, such as 10 Hz.

[0036] The checking operation may also include controlling the socket based on a constant torque as an alternative to pulses, where the constant torque may be set small enough to separate the power tool from the joint, whereupon the constant torque begins to rotate the socket, and based on this rotation it may be determined that the power tool has separated from the joint.

[0037] The at least one parameter may include rotational position, rotational speed, rotational acceleration, torque and / or current.

[0038] The method may further include determining whether the tightening operation was successful and commanding the performance of a check operation upon determining that the tightening operation was successful. If the tightening operation was not successful, an alert may be issued to an operator. If the tightening operation was not successful, the socket may be prevented from returning to the open position.

[0039] The power tool may include an actuation element that is actuated by a human operator, in which case the method may include commanding the performance of the tightening and checking operations regardless of whether the actuation element is actuated. Once the tightening operation is complete, the operator may simply move the power tool away from the joint without releasing the actuation element. Once the socket is released from the joint, it automatically returns to the open position.

[0040] According to a fifth aspect, there is provided a control system for controlling a power tool for tightening a joint comprising a base element having a base opening, a socket having a socket opening, a motor arranged to drive the socket, and a control system configured to control the motor, wherein the socket is rotatable about a socket axis from an open position in which the socket opening is aligned with the base opening, the control system comprising at least one data processing device and at least one memory storing at least one computer program, the at least one computer program including program code that, when executed by the at least one data processing device, causes the at least one data processing device to perform the following steps: instructing the at least one data processing device to perform a tightening operation; instructing the at least one data processing device to perform a check operation after the tightening operation; monitoring a response of at least one parameter associated with the socket to the check operation; determining based on the response whether the socket is free to rotate; and instructing the socket to be positioned in the open position upon determining that the socket is free to rotate.

[0041] The at least one computer program may comprise program code which, when executed by the at least one data processing apparatus, causes the at least one data processing apparatus to perform any of the steps according to the fourth aspect.

[0042] According to a sixth aspect, there is provided a power tool comprising a socket according to the first aspect, a control system according to the third aspect and / or a control system according to the fifth aspect. The power tool may be used to apply torque to a joint. The power tool may be handheld.

[0043] Further details, advantages and aspects of the present disclosure will become apparent from the following description taken in conjunction with the drawings. [Brief description of the drawings]

[0044] [Figure 1a] 1 is a schematic side view of a power tool. [Figure 1b] FIG. 2 is a schematic top view of the power tool. [Diagram 2] 1 is a schematic partial cross-sectional side view of a power tool with the tool head removed from the body. [Figure 3a] FIG. 2 is a cross-sectional side view of the tool head. [Figure 3b] FIG. 2 is a schematic top view of components of a tool head. [Figure 4] FIG. 2 is a perspective view of a socket of a power tool. [Figure 5a] FIG. 13 is a top view of a socket including a positioning device. [Figure 5b] 13A-13C are schematic top views of sockets including further examples of positioning devices. [Figure 6a] FIG. 2 is a schematic side view of an unassembled joint including a coupling and a bolt. [Figure 6b] FIG. 1 is a schematic side view of the joint during installation of a bolt into the coupling using a power tool. [Figure 6c] 2 is a schematic side view of the joint with the power tool removed from the joint; FIG. [Figure 7a] FIG. 4 is a schematic diagram showing the current to the motor as a function of time during a check operation. [Figure 7b] FIG. 11 is a schematic diagram showing rotational position as a function of time during a checking operation. [Figure 7c] FIG. 4 is a schematic diagram showing the rotational speed as a function of time during a checking operation. [Figure 7d] FIG. 4 is a schematic diagram showing rotational acceleration as a function of time during a checking operation. [Figure 7e] FIG. 4 is a schematic diagram showing torque as a function of time during a checking operation. [Figure 8a] 1 is a schematic perspective view of a further example of a socket for a power tool; FIG. [Figure 8b] FIG. 8b is a schematic side view of the socket of FIG. 8a. [Figure 8c] FIG. 8B is a schematic top view of the socket of FIGS. 8a and 8b. [Figure 9a] These are schematic top views of the sockets of FIGS. 8a to 8c. [Figure 9b] These are schematic top views of the socket and the joint of FIG. 9a when the socket is rotated in the tightening direction. [Figure 9c] These are schematic top views of the socket and the joint of FIG. 9a when the socket is rotated in the releasing direction. [Figure 10a] These are schematic side views of the socket and the joint of FIG. 9a. [Figure 10b] These are schematic side views of the socket and the joint of FIG. 9c when the socket is rotated in the releasing direction.

DETAILED DESCRIPTION OF THE INVENTION

[0045] Hereinafter, a socket for a power tool including at least one internal inclined surface, a control method for a power tool including such a socket, a control system for controlling a power tool including such a socket, a control method for a power tool including a check operation, a control system for controlling a power tool to perform a check operation, and a power tool will be described. Note that the same or similar reference numerals are used for the display of the same or similar structural features.

[0046] FIG. 1a is a schematic side view of the power tool 10, and FIG. 1b is a schematic top view of the power tool 10. Referring to FIGS. 1a and 1b together, the power tool 10 includes a main body 12 and a tool head 14. The tool head 14 is detachably attached to the main body 12 in this example. The main body 12 is exemplified as a housing here.

[0047] The power tool 10 in this example is a hand-held open-end type power tool for tightening. The power tool 10 can be driven electrically, for example. As shown in FIG. 1b, the power tool 10 can be used to tighten a bolt 16 on a threaded coupling 18, for example. The coupling 18 can surround a pipe 20.

[0048] The power tool 10 of this example further includes an actuation element 22, illustrated here as a lever rotatable relative to the body 12 by manual actuation.

[0049] The tool head 14 includes a base element 24. The base element 24 includes a base opening 26 at a distal end thereof.

[0050] The tool head 14 further includes a socket 28a having a socket opening 30. Thus, the socket 28a is an open-ended socket and the power tool 10 is an open-ended power tool. The socket 28a is rotatable relative to the base element 24 about a socket axis 32. In Figures 1a and 1b, the socket 28a is in an open position 34. In the open position 34, the socket opening 30 is aligned with the base opening 26 such that the pipe 20 can be radially received relative to the socket axis 32. The power tool 10 can then be moved axially along the pipe 20 to axially receive the bolt 16 within the socket opening 30.

[0051] Figure 2 is a schematic, partial cross-sectional side view of the power tool 10. The tool head 14 is now removed from the body 12. As shown in Figure 2, the body 12 in this example includes a drive shaft 36. The drive shaft 36 is rotatable about a drive axis 38. In this example, the drive axis 38 is parallel to the socket axis 32 when the tool head 14 is attached to the body 12.

[0052] The power tool 10 of this example further includes a control system 40. The control system 40 is here provided in the main body 12. The control system 40 includes a data processing device 42 and a memory 44. A computer program is stored in the memory 44. The computer program includes program code that, when executed by the data processing device 42, causes or instructs the data processing device 42 to perform various steps as described herein.

[0053] The power tool 10 of this example further includes an electric motor 46 housed within the body 12. The motor 46 rotatably drives a motor shaft 48. The control system 40 is in signal communication with the motor 46, and here controls operation of the motor 46 by sending an electrical current 50 to the motor 46.

[0054] The power tool 10 of this example further includes a reduction gear 52 and an intermediate shaft 54. The reduction gear 52 is configured to transmit the rotation of the motor shaft 48 at a first rotational speed to the rotation of the intermediate shaft 54 ​​at a second rotational speed lower than the first rotational speed. The rotation of the intermediate shaft 54 ​​is transmitted to the rotation of the drive shaft 36 via the bevel gear 56. In this manner, the power tool 10 is configured to transmit the rotation of the motor shaft 48 to the rotation of the drive shaft 36. The reduction gear 52, the intermediate shaft 54, and the bevel gear 56 constitute one of many examples of a motor transmission 58 configured to transmit the rotation of the motor 46 to the rotation of the drive shaft 36.

[0055] The power tool 10 further includes a position sensor 60. The position sensor 60 is positioned to measure the position of the motor shaft 48, here a rotational position 62.

[0056] The power tool 10 further includes a torque sensor 64. The torque sensor 64 is positioned to measure a torque 66, illustrated here as an input torque to the reduction gear 52.

[0057] Figure 3a is a schematic cross-sectional side view of tool head 14, and Figure 3b is a schematic top view of components of tool head 14. With reference collectively to Figures 3a and 3b, the example tool head 14 includes a drive member 68. The drive member 68 is rotatable relative to the base element 24 about a drive axis 38. The drive member 68 is illustrated here as a hollow shaft arranged to receive a drive shaft 36 that is driven by the drive member 68.

[0058] The tool head 14 further includes a drive transmission 70. The drive transmission 70 is configured to transmit rotation of the drive member 68 about the drive shaft 38 to rotation of the socket 28a about the socket shaft 32. In this example, the ratio between the drive member 68 and the socket 28a is 1:1. The drive transmission 70 of this example includes a first gear 72 meshing with a toothed portion of the drive member 68, a second gear 74 meshing with the first gear 72, a third gear 76 meshing with the second gear 74, a first fourth gear 78a meshing with the third gear 76 and each of the toothed drive profiles 80 of the socket 28a, and a second fourth gear 78b meshing with the third gear 76 and each of the drive profiles 80 of the socket 28a. The drive profile 80 is thus drivingly engaged by the fourth gears 78a and 78b. The power tool 10 is configured to transmit rotation of the motor shaft 48 through a motor transmission 58 and a drive transmission 70 to rotation of the socket 28a.

[0059] The rotational position of the socket 28a may be determined based on the rotational position of the motor shaft 48. Additionally, the torque applied to the socket 28a may be determined based on the torque 66 at the reduction gear 52.

[0060] 4 is a schematic perspective view of socket 28a. Socket 28a includes a cylindrical portion 82 and an inner portion 84. Inner portion 84 is disposed radially inward of cylindrical portion 82 relative to socket axis 32. As shown, a drive profile 80 is provided on the outside of cylindrical portion 82.

[0061] The cylindrical portion 82 includes an end surface 86 and a plurality of engagement surfaces 88. Each engagement surface 88 is disposed on the inside of the cylindrical portion 82. Furthermore, each engagement surface 88 is parallel to the socket axis 32. In this example, the cylindrical portion 82 includes four full-sized engagement surfaces 88 and two smaller engagement surfaces 88 that are bounded by the socket opening 30. As shown in FIG. 4, the socket opening 30 extends radially through the cylindrical portion 82 and the inner portion 84 relative to the socket axis 32.

[0062] The inner portion 84 includes a stopping surface 90. The stopping surface 90 and the end surface 86 are offset from one another in a direction parallel to the socket axis 32. In this example, each of the end surface 86 and the stopping surface 90 are flat and perpendicular to the socket axis 32. In FIG. 4, the stopping surface 90 is located below the end surface 86. The engagement surface 88 is disposed between the end surface 86 and the stopping surface 90 along a direction parallel to the socket axis 32.

[0063] 5a is a schematic top view of the socket 28a. The socket 28a in this example includes a positioning device 92a. The positioning device 92a in this example includes a positioning base 94, a spring 96, and a stopper 98. The positioning device 92a further includes a recess 100, such as in the cylindrical portion 82 of the socket 28a, offset from the drive profile 80. The positioning base 94 can be fixed to the base element 24.

[0064] As shown in Fig. 5a, when the socket 28a is rotated in a counterclockwise direction, the recess 100 can pass the stopper 98. Therefore, the socket 28a in Fig. 5a can rotate in a counterclockwise direction endlessly. When the socket 28a rotates in a clockwise direction in Fig. 5a and the recess 100 reaches the stopper 98, the spring 96 pushes the stopper 98 into the recess 100, and the socket 28a stops at the open position 34.

[0065] 5b is a schematic top view of the socket 28a. The socket 28a includes a further example of a positioning device 92b. The positioning device 92b can be located on the cylindrical portion 82 offset from the drive profile 80 in a direction parallel to the socket axis 32.

[0066] The positioning device 92b in this example is a sensor that includes an active component 102 and a passive component 104. In this example, the active component 102 is a Hall effect sensor fixed to the base element 24, and the passive component 104 is a magnet fixed, such as to the cylindrical portion 82 of the socket 28a offset from the drive profile 80. The active component 102 is in signal communication with the control system 40. When the socket 28a is in the open position 34, the active component 102 detects the proximity of the passive component 104.

[0067] Figure 6A is a schematic side view of an unassembled joint 106. The joint 106 in this embodiment includes a pipe 20, a coupling 18 and a bolt 16, as previously shown in Figure 1b. The coupling 18 includes an external thread 108. In Figure 6a, the bolt 16 surrounds the pipe 20 but is not threaded into the external thread 108.

[0068] The bolt 16 in this example includes six engageable surfaces 110 and twelve corners 112 between the engageable surfaces 110. Six of the corners 112 are located at one end of the bolt 16 (the left end in FIG. 6a) and six of the corners 112 are located at the opposite end (the right end in FIG. 6a).

[0069] Once the socket 28a is in the open position 34, the power tool 10 may be moved to receive the pipe 20 through the socket opening 30 in a radial direction relative to the socket axis 32. The power tool 10 may then be moved axially along the pipe 20 to receive the bolt 16 into the socket 28a. Once the bolt 16 is received in the socket 28a, each engagement surface 88 is parallel with an associated engageable surface 110 of the bolt 16. The power tool 10 may then be moved axially (to the right in FIG. 6a) relative to the bolt 16 until the bolt 16 abuts a stop surface 90 in the socket 28a.

[0070] FIG. 6b is a schematic side view of the joint 106 during the installation of the bolt 16 into the coupling 18 using the power tool 10. Here, a tightening operation of the joint 106 is taking place. In this example, the control system 40 commands the motor 46 to perform a tightening operation in response to the actuation of the actuation element 22. During the tightening operation, the socket 28a rotates the bolt 16 in the tightening direction 114 to tighten the joint 106. During the tightening operation, the socket 28a is first controlled at a constant rotation speed until a torque threshold is reached. The rotation speed can then be reduced until the target torque of the joint 106 is reached. If the tightening operation is successful, a green light is displayed. If the tightening operation is not successful, a red light is displayed. Once the tightening operation is completed, the control system 40 immediately commands the execution of a check operation, for example as described in FIGS. 7a-7e. The check operation can be performed conditional on the success of the tightening operation.

[0071] 6c is a schematic side view of the joint 106 when the power tool 10 is removed from the joint 106. The operator can remove the power tool 10 from the joint 106 immediately after completing the tightening operation. The removal of the power tool 10 from the joint 106 can be detected by a checking operation.

[0072] FIG. 7a is a schematic diagram showing the current 50 to the motor 46 during a check operation as a function of time t. As shown, the control system 40 transmits pulses 116a-116c of current 50 to the motor 46 during the check operation. The current 50 is an example of a parameter associated with the socket 28a. A first pulse 116a is transmitted at time t1, a second pulse 116b is transmitted at time t2, and a third pulse 116c is transmitted at time t3. In this example, the current 50 is zero between the pulses 116a-116c. The time step between the pulses 116a-116c can be, for example, 0.1 seconds. The socket 28a engages the bolt 16 at times t1 and t2. The socket 28a disengages from the bolt 16 at time t3.

[0073] In this example, each pulse 116a-116c is a positive pulse that commands the socket 28a to rotate in an unlocking direction opposite to the fastening direction 114. However, the pulses 116a-116c could also be negative pulses that command the socket 28a to rotate in the fastening direction 114, or could command the socket 28a to rotate alternately in the unlocking and fastening directions 114.

[0074] 7b is a schematic diagram showing the rotational position 62 as a function of time t during a check operation. A linear relationship exists between the rotational position 62 measured by the position sensor 60 and the rotational position of the socket 28a. Thus, the position 62 is a further example of a parameter associated with the socket 28a. The control system 40 monitors the response of the rotational position 62 to the pulses 116a-116c.

[0075] At time t1, the socket 28a rotates slightly from the starting position within the range of play between the engagement surface 88 of the socket 28a and the engageable surface 110 of the bolt 16. The socket 28a comes to a stop shortly after time t1, which allows the control system 40 to determine that the socket 28a has engaged the joint 106.

[0076] At time t2, there is no change in rotational position 62. This allows control system 40 to conclude that socket 28a is still engaged with joint 106.

[0077] At time t3, the socket 28a rotates past the threshold angular distance 118. Based on this, the control system 40 can conclude that the socket 28a is not engaged with the joint 106. The threshold angular distance 118 can be, for example, between 20 degrees and 30 degrees.

[0078] FIG. 7c is a schematic diagram illustrating the rotational speed 120 of the socket 28a as a function of time t during a check operation. The control system 40 determines the rotational speed 120 based on the measured rotational position 62. There is a linear relationship between the rotational speed 120 determined based on the rotational position 62 and the rotational speed of the socket 28a. Thus, the rotational speed 120 is a further example of a parameter related to the socket 28a. The control system 40 monitors the response of the rotational speed 120 to the pulses 116a-116c. The rotational speed 120 increases slightly for a short period of time at time t1. The rotational speed 120 is zero at time t2. The rotational speed 120 increases at time t3 to indicate that the socket 28a has been released from the bolt 16.

[0079] FIG. 7d is a schematic diagram illustrating the rotational acceleration 122 of the socket 28a during the check operation as a function of time t. The control system 40 determines the rotational acceleration 122 based on the measured rotational position 62. There is a linear relationship between the rotational acceleration 122 and the rotational acceleration of the socket 28a. Thus, the rotational acceleration 122 is a further example of a parameter related to the socket 28a. The control system 40 monitors the response of the rotational acceleration 122 to the pulses 116a-116c. At time t1, there is a small amount of rotational acceleration 122 for a short period of time. The rotational acceleration 122 is zero at time t2. The rotational acceleration 122 increases at time t3 to indicate that the socket 28a has been released from the bolt 16.

[0080] FIG. 7e is a schematic diagram illustrating the torque 66 of the socket 28a during the check operation as a function of time t. The torque applied to the socket 28a can be determined based on the torque 66 measured by the torque sensor. Thus, the torque 66 is a further example of a parameter related to the socket 28a. The control system 40 monitors the response of the torque 66 to the pulses 116a-116c. The torque 66 increases until it reaches a torque threshold 124 shortly after time t1. The torque threshold 124 can be substantially lower than the tightening torque, for example 1 Nm. When the torque 66 reaches the torque threshold 124, the pulses 116a stop. The torque 66 increases again until it reaches the torque threshold 124 at time t2, and the pulses 116b stop. However, at time t3, there is no increase in the torque 66. After time t3, the socket 28a rotates beyond the threshold angular distance 118 from the starting position without the torque 66 reaching the torque threshold 124. This indicates, among other things, that the power tool 10 has separated from the joint 106 .

[0081] In this example, each pulse 116a-116c stops when the torque 66 reaches the torque threshold 124, and the socket 28a remains in this position until the next pulse 116a-116c. Optionally, the socket 28a can be returned to the starting position after each pulse 116a-116c.

[0082] When the control system 40 determines that the socket 28a is not engaged with the joint 106, it automatically commands the positioning of the socket 28a in the open position 34 immediately, regardless of how or whether the actuation element 22 is actuated in this example. Positioning the socket 28a in the open position 34 upon concluding that the power tool 10 is released from the joint 106 allows the rotational speed 120 to increase. Thus, the operator can simply remove the power tool 10 from the joint 106 and the pipe 20 upon completion of the tightening operation. The power tool 10 can automatically address this purpose without requiring any further command from the operator to position the socket 28a in the open position 34. This allows for significant time savings.

[0083] FIG. 8a is a schematic perspective view of a further example of a socket 28b of the power tool 10. FIG. 8b is a schematic side view of the socket 28b, and FIG. 8c is a schematic top view of the socket 28b. With reference to FIGS. 8a-8c collectively, the socket 28b differs from the socket 28a by further including an internal bevel 126. The socket 28b of this example includes four internal bevels 126. The internal bevels 126 are disposed inside the cylindrical portion 82. Here, each internal bevel 126 is formed by a cutout in the respective engagement surface 88. As shown, each internal bevel 126 of this example is straight and extends from the stop surface 90 to the end surface 86. As shown in FIG. 8c in particular, each internal bevel 126 is located between the end surface 86 and the stop surface 90 when viewed in a plane transverse to the socket axis 32.

[0084] Figure 9a is a schematic top view of socket 28b receiving joint 106, and Figure 10a is a schematic side view of socket 28b and joint 106. In Figures 9a and 10a, socket 28b is in the same position relative to bolt 16 as in Figure 6b. As shown in Figure 9a, each engagement surface 88 is aligned with a unique engageable surface 110 on bolt 16.

[0085] 9b is a schematic top view of the socket 28b and the joint 106. Rotation of the socket 28b in the tightening direction 114 rotates the bolt 16 as indicated by the arrow 128. As can be seen, the socket 28b is configured to tighten the bolt 16 by rotation in the tightening direction 114 in a conventional manner.

[0086] Fig. 9c is a schematic top view of the socket 28b and the joint 106 when the socket 28b is rotated in a release direction 130 opposite to the tightening direction 114, and Fig. 10b is a schematic side view of the socket 28b and the joint 106. Here, the socket 28b rotates about the socket axis 32 relative to the stationary bolt 16. When the socket 28b rotates in the release direction 130, the corners 112 of the bolt 16 (here, the four corners 112 of the bolt 16) move along their respective internal beveled surfaces 126. This causes the power tool 10 to move axially away from the joint 106 relative to the socket axis 32 as shown by the arrow 132.

[0087] If the power tool 10 includes the socket 28b, the check operation can also be performed immediately after completion of the tightening operation. In this case, the check operation can instead include a release operation that includes rotating the socket 28b in the release direction 130. In this way, the operator does not need to lift the power tool 10 off the bolt 16. In this example, the control system 40 can still detect when the socket 28b is no longer engaged with the joint 106, such as when the torque 66 is reduced. The release operation does not need to be performed with pulses 116a-116c. Once the socket 28b is released from the bolt 16, the rotational speed 120 can be increased until the socket 28b reaches the open position 34.

[0088] The same software that works with both sockets 28a and 28b can be used in power tool 10 where the checking operation involves applying a torque to socket 28b in release direction 130. This torque can be small enough so as not to loosen joint 106 if socket 28a is being used, but large enough to separate socket 28b due to the engagement between internal bevel 126 and corner 112.

[0089] Although the present disclosure has been described with reference to exemplary embodiments, it will be understood that the present invention is not limited to the above. For example, it will be understood that the dimensions of the parts may vary as necessary. Accordingly, it is intended that the present invention be limited only by the scope of the appended claims.

Claims

1. A socket (28b) for a power tool (10) arranged to rotate about a socket axis (32), comprising: a cylindrical portion (82) having an end face (86) and a plurality of engagement surfaces (88) parallel to the socket axis (32) inside the cylindrical portion (82); an inner part (84) located radially inside said cylindrical part (82) with respect to said socket axis (32) and having a stop surface (90) offset from said end face (86), said engagement surface (88) being located between said stop surface (90) and said end face (86); a socket opening (30) extending radially relative to said socket axis (32) and through said cylindrical portion (82) and said inner portion (84); Equipped with the cylindrical portion (82) includes at least one internal bevel (126) extending on the inside of the cylindrical portion (82) and away from the stop surface (90); A socket (28b).

2. The at least one internal bevel (126) includes a plurality of internal bevels (126). The socket (28b) of claim 1.

3. Each internal bevel (126) is straight. Socket (28b) according to claim 1 or 2.

4. Each internal bevel (126) extends from said stop surface (90) to said end surface (86); A socket (28b) according to any one of claims 1 to 3.

5. said cylindrical portion (82) includes, on the outside of said cylindrical portion (82), a circular drive profile (80) concentric with said socket shaft (32) and in driving engagement with wheels (78a, 78b); A socket (28b) according to any one of claims 1 to 4.

6. A method of controlling a power tool (10) for tightening a joint (106), the power tool (10) comprising a base element (24) having a base opening (26), a socket (28b) according to any one of claims 1 to 5, a motor (46) arranged to drive the socket (28b), and a control system (40) configured to control the motor (46), the socket (28b) being rotatable about the socket axis (32) from an open position (34) in which the socket opening (30) is aligned with the base opening (26), the method comprising: - said control system (40) commands the execution of a tightening operation by said socket (28b) for tightening said joint (106); - said control system (40) commands the execution of a release action by said socket (28b) after execution of said clamping action; The method of claim 1, further comprising:

7. 1. A control system (40) for controlling a power tool (10) tightening a joint (106), the power tool (10) comprising a base element (24) having a base opening (26), a socket (28b) according to any one of claims 1 to 5, a motor (46) arranged to drive the socket (28b), and a control system (40) configured to control the motor (46), the socket (28b) being rotatable about the socket axis (32) from an open position (34) in which the socket opening (30) is aligned with the base opening (26), the control system (40) comprising at least one data processing device (42) and at least one memory (44) storing at least one computer program, the at least one computer program, when executed by the at least one data processing device (42), being adapted to transmit to the at least one data processing device (42) - commanding the execution of a tightening operation by said socket (28b) for tightening said joint (106); - commanding the execution of a release operation by said socket (28b) after the execution of said clamping operation; comprising program code for executing A control system (40).

8. A method of controlling a power tool (10) for tightening a joint (106), the power tool (10) comprising a base element (24) having a base opening (26), sockets (28a, 28b) having socket openings (30), a motor (46) arranged to drive the sockets (28a, 28b), and a control system (40) configured to control the motor (46), the sockets (28a, 28b) being rotatable about a socket axis (32) from an open position (34) in which the socket opening (30) is aligned with the base opening (26), the method comprising: - said control system (40) commands the execution of a tightening operation by said sockets (28a, 28b) for tightening said joint (106); - said control system (40) commands the execution of a check operation by said sockets (28a, 28b) after the execution of said tightening operation; said control system (40) monitoring the response of at least one parameter associated with said sockets (28a, 28b) to said checking operation; - said control system (40) determining, based on said response, whether said sockets (28a, 28b) are engaged with said joints (106); - commanding said sockets (28a, 28b) to be positioned in said open position (34) when said control system (40) determines that said sockets (28a, 28b) are not engaged with said joint (106); The method of claim 1, further comprising:

9. The power tool (10) comprises a socket (28b) according to any one of claims 1 to 5. The method according to claim 8.

10. The check operation includes a release operation.

10. The method of claim 9.

11. the checking operation includes controlling the sockets (28a, 28b) based on a rotational position (62), a rotational speed (120), a rotational acceleration (122), a torque (66), and / or a current (50).

11. The method according to any one of claims 8 to 10.

12. the checking operation includes controlling the sockets (28a, 28b) based on a torque (66) that is less than a maximum torque (66) during the tightening operation.

12. The method according to any one of claims 8 to 11.

13. The checking operation includes controlling the sockets (28a, 28b) based on a current (50) that is less than a maximum current (50) during the tightening operation.

13. The method according to any one of claims 8 to 12.

14. said sockets (28a, 28b) are instructed to perform said checking operations with pulses (116a-116c); 14. The method according to any one of claims 8 to 13.

15. said sockets (28a, 28b) being controlled based on a relatively large torque (66) during said pulses (116a-116c) and based on a relatively small, zero or negative torque (66) between said pulses (116a-116c); The method of claim 14.

16. said sockets (28a, 28b) being controlled based on a relatively large current (50) during said pulses (116a-116c) and based on a relatively small, zero or negative current (50) between said pulses (116a-116c); 16. The method according to claim 14 or 15.

17. The pulses (116a-116c) have a frequency of at least 5 Hz.

17. The method according to any one of claims 14 to 16.

18. the at least one parameter includes a rotational position (62), a rotational speed (120), a rotational acceleration (122), a torque (66), and / or a current (50); 18. The method according to any one of claims 8 to 17.

19. determining whether the tightening operation is successful; and instructing execution of the checking operation when determining that the tightening operation is successful.

19. The method according to any one of claims 8 to 18.

20. The power tool (10) includes an actuation element (22) that is actuated by a human, and the method includes commanding the execution of the tightening operation and the checking operation regardless of whether the actuation element (22) is actuated.

20. The method according to any one of claims 8 to 19.

21. 1. A control system (40) for controlling a power tool (10) to tighten a joint (106), the power tool (10) comprising: a base element (24) having a base opening (26); sockets (28a, 28b) having socket openings (30); a motor (46) arranged to drive the sockets (28a, 28b); and a control system (40) configured to control the motor (46), the sockets (28a, 28b) being rotatable about a socket axis (32) from an open position (34) in which the socket openings (30) are aligned with the base openings (26); the control system (40) comprising at least one data processing device (42) and at least one memory (44) having stored therein at least one computer program, the at least one computer program, when executed by the at least one data processing device (42), for transmitting to the at least one data processing device (42) instructions for: - commanding the execution of a clamping operation by said sockets (28a, 28b); - commanding the execution of a checking operation by said sockets (28a, 28b) after said tightening operation; - monitoring a response of at least one parameter associated with said sockets (28a, 28b) to said check operation; - determining, based on said response, whether said sockets (28a, 28b) are free to rotate; - commanding said sockets (28a, 28b) to be placed in said open position (34) when it is determined that said sockets (28a, 28b) are free to rotate; comprising program code for causing the A control system (40).

22. The at least one computer program comprises a program code which, when executed by the at least one data processing device (42), causes the at least one data processing device (42) to perform the steps according to any one of claims 9 to 20.

22. The control system (40) of claim 21.

23. The socket (28b) according to any one of claims 1 to 5, the control system (40) according to claim 7 and / or the control system (40) according to claim 21 or 22. A power tool (10).

Images