A handheld bending device

Abstract

A handheld bending device (1) for bending or straightening a power cable (2) comprises a central bending part (9) including a contact surface (12) for contacting a power cable (2) and two side bending parts (11) including respective contact surfaces (13) for contacting a power cable(2). The contact surface (12) of the central bending part (9) is directed in opposite direction with respect to the contact surfaces (13) of the side bending parts (11) and lies between the contact surfaces (13) of the side bending parts (11) in a bending plane. The handheld bending comprises a spindle (7) having a spindle axis and one end to which the central bending part (9) is mounted freely rotatable about the spindle axis and an opposite end for being drivably connected to a drive shaft (5) of a drive tool (3). The handheld bending comprises a spindle nut (8) which is drivably mounted to the spindle (7) at a distance from the central bending part (9) and to which the side bending parts (11) are mounted.

Description

[0001] A handheld bending device

[0002] The present invention relates to a handheld bending device for bending or straightening a power cable .

[0003] Bending or straightening a power cable can be done manually, but becomes more di f ficult with increasing diameter and sti f fness of the power cable . For example , a power cable must be inserted from outside a trans former house and pre-bent outside the trans former house and / or bent in an angle inside the trans former house . Usually, available space is very limited due to low ceilings or the like . Nevertheless , due to electri fication there is a growing demand of installing still thicker and sti f fer power cables and usually several persons are working together to bend or straighten a thick power cable . Bending power cables requires special treatment since kinking must be avoided and a bending radius may not be too small . Furthermore , when a power cable is provided with a polymeric insulation sheath, bending must be performed carefully .

[0004] An obj ect of the invention is to provide a handheld bending device than can be operated easily in spaces with limited elbow room .

[0005] This obj ect is accomplished with the handheld bending device according to the invention which comprises a central bending part including a contact surface for contacting a power cable , two side bending parts including respective contact surfaces for contacting a power cable , wherein the contact surface of the central bending part is directed in opposite direction with respect to the contact surfaces of the side bending parts and lies between the contact surfaces of the side bending parts in a bending plane , a spindle having a spindle axis and one end to which the central bending part is mounted freely rotatable about the spindle axis and an opposite end for being drivably connected to a drive shaft of a drive tool , and a spindle nut which is drivably mounted to the spindle at a distance from the central bending part and to which the side bending parts are mounted .

[0006] An advantage of the handheld bending device according to the invention is that it is relatively compact since it can be used in the bending plane . The handheld bending device can be operated by one person . It is noted that the contact surface of the central bending part is directed to the contact surfaces of the side bending parts such that a power cable can be held between the central bending part and the side bending parts . One or more of the contact surfaces may be curved in a plane perpendicular to the bending plane or envelope an imaginary arc so as to lock a power cable at the corresponding central bending part and / or the side bending parts in a direction perpendicular to the bending plane .

[0007] The side bending parts may be mounted to opposite portions of the spindle nut at a distance from the spindle through bars . The bars may be parallel to the spindle .

[0008] The bars may lie in the bending plane .

[0009] Each of the bars may be pivotally mounted to the corresponding side bending part , which avoids excessive friction between the contact surfaces of the side bending parts and the power cable during bending or straightening a power cable . It is also possible that the bars are pivotally mounted to the spindle nut , which provides the opportunity to place the side bending parts at di f ferent distances from the central bending part on a power cable , hence influencing required torque on the spindle to bend the power cable . In this case the bars may be lockable to the spindle nut in order to prevent the bars from spreading with respect to each other during a bending action .

[0010] The spindle nut may be elongate in the bending plane in transverse direction of the spindle .

[0011] The elongate spindle nut and the bars may form a U- shape .

[0012] The bars may be formed integrally with the spindle nut .

[0013] In a preferred embodiment the handheld bending device is provided with a coupling part which is configured to be mounted to a blocking portion of a drive tool such that the coupling part is blocked with respect to the blocking portion about the spindle axis , which coupling part is mounted or mountable to the spindle nut such that rotation of the coupling part with respect to the spindle nut about the spindle axis is blocked or blocked outside a predefined angle between the coupling part and the spindle nut , since this means that in the event that a drive shaft of a drive tool is coupled to the spindle and the coupling part is mounted to the spindle nut an operator who operates the drive tool does not feel a reaction force since the reaction force is absorbed by the blocking portion of the drive tool , hence facilitating a bending operation . I f the coupling part and the spindle nut do not allow a mutual rotation the coupling part may be part of the spindle nut or the coupling part may be formed integrally with the spindle nut .

[0014] The above-mentioned predefined angle may be 60 ° , but numerous alternative angles are conceivable . In practice the predefined angle may be smaller than 90 ° .

[0015] In an embodiment one of the coupling part and the spindle nut has pins which fit in cooperating slot holes in the other one of the coupling part and the spindle nut for allowing rotation of the coupling part with respect to the spindle nut , which slot holes are located at opposite sides of the spindle when the coupling part is mounted to the spindle nut . The slot holes and the pins provide a certain degree of play, which facilitates a coupling between the spindle nut and the coupling part , such that an operator can perform the coupling quickly . The slot holes may be arcuate .

[0016] The handheld bending device may comprise a drive tool including a housing and a drive shaft , which drive shaft is drivable in rotational direction with respect to the housing about a drive shaft axis , wherein the spindle is drivably connected are connectable to the drive shaft .

[0017] The drive tool may be provided with a blocking portion which is mounted or mountable to the coupling part such that the coupling part is blocked with respect to the blocking portion about the spindle axis . In this case the drive shaft is rotatable with respect to the blocking portion .

[0018] Preferably, the housing is freely rotatable with respect to the blocking portion about the drive shaft axis , since this facilitates operation of the handheld bending device in a small space .

[0019] The drive shaft axis and the spindle axis may coincide when the drive shaft and the spindle are drivably connected to each other . This means that the drive shaft and the spindle are aligned, which results in a compact handheld bending device .

[0020] In a practical embodiment the housing has an L-shape including a first leg which is directed in the same direction as the drive shaft and a second leg which is provided with a switch for switching the drive tool on and of f . When the housing is freely rotatable with respect to the blocking portion the second leg can be angled with respect to the bending plane at wish . This appears to facilitate handling of the handheld bending device .

[0021] The contact surface of the central bending part may be directed to the drive tool , which means that during a bending action the central bending part will pull on the power cable whereas the side bending parts are pushing on the power cable as seen from the spindle nut .

[0022] In a preferred embodiment the central bending part is releasably mounted to the spindle , since this facilitates to place the handheld bending device at any desired location of a power cable . Furthermore , the central bending part may be replaced by variants which have di f ferent dimensions that fit to power cables having di f ferent diameters .

[0023] For similar reasons , the side bending parts may be releasably mounted to the spindle nut .

[0024] The central bending part may be pivotally mounted to the spindle .

[0025] The invention will hereafter be elucidated with reference to very schematic drawings showing an embodiment of the invention by way of example .

[0026] Fig . 1 is a perspective view of a part of an embodiment of a handheld bending device according to the invention .

[0027] Fig . 2 is an exploded view of the handheld bending device as shown in Fig . 1 .

[0028] Fig . 3 is an enlarged view of a part of Fig . 2 .

[0029] Figs . 1-3 show an embodiment of a handheld bending device 1 according to the invention . The handheld bending device 1 is suitable for bending or straightening a power cable 2 , which is illustrated in Fig . 1 . The handheld bending device 1 comprises an electrical drive tool 3 which has an L-shaped housing 4 and a drive shaft 5 which is drivable in rotational direction with respect to the housing 4 about a drive shaft axis .

[0030] Referring to Figs . 2 and 3 , an end portion of the drive shaft 5 fits in an intermediate part 6 which in turn is drivably coupled to a spindle 7 . The spindle 7 has a spindle axis which coincides with the drive shaft axis . A spindle nut 8 is drivably mounted on the spindle 7 such that when the drive tool 3 rotates the spindle 7 the spindle nut 8 translates along the spindle axis . The spindle 7 may have a multi-start thread in order to obtain a multi- fold stroke with one revolution of the spindle 7 .

[0031] The handheld bending device 1 is provided with a central bending part 9 and two side bending parts 11 for exerting a bending force on the power cable 2 . The central bending part 9 has a contact surface 12 for contacting the power cable 2 , which contact surface 12 is directed to the drive tool 4 . The side bending parts 11 have respective contact surfaces 13 for contacting the power cable 2 , which contact surfaces 13 are directed in opposite direction with respect to the contact surface 12 of the central bending part 9 . The contact surface 12 of the central bending part 9 lies between the contact surfaces 13 of the side bending parts 11 in a bending plane as seen along the power cable 2 .

[0032] The central bending part 9 is releasably mounted to the spindle 7 through a block 14 . The block 14 has a through-hole through which the spindle 7 passes such that the block 14 is freely rotatable with respect to the spindle 7 about the spindle axis without being translated along the spindle 7 . The central bending part 9 has a U-shape of which two legs are provided with respective hooks 16 behind which a pin 17 of the block 14 can be hooked . This means that the central bending part 9 can be coupled to the block 14 at each location along the power cable 2 . The central bending part 9 is also rotatable about the pin 17 .

[0033] The side bending parts 11 are coupled to the spindle nut 8 through parallel bars 18 , which lie in the bending plane . The spindle nut 8 is elongate in the bending plane in transverse direction of the spindle 7 and the bars 18 are mounted to opposite end portions of the spindle nut 8 at a distance from the spindle 7 . In this case the spindle nut 8 and the bars 18 are formed integrally as a U-shaped unit . The side bending parts 11 have U-shapes and are pivotally mounted to the bars 18 . In an alternative embodiment (not shown) the bars 18 may be pivotally mounted to the spindle nut 8 . In this case the bars 18 may be lockable to the spindle nut 8 in order to prevent the bars 18 from spreading with respect to each other during a bending action .

[0034] Similar to the central bending part 9 the side bending parts 11 may be releasably mounted to the bars 18 . This means that the central bending part 9 and the side bending parts 11 can be replaced by a di f ferent central bending part 9 and di f ferent side bending parts 11 which have di f ferent dimensions that match with a power cable of a di f ferent diameter .

[0035] The drive tool 3 is connected to the spindle nut 8 through a coupling part 19 . The intermediate part 6 extends through the coupling part 19 and forms a coupling between the spindle 7 and the drive shaft 5 . Hence , the intermediate part 6 is rotatably mounted inside the coupling part 19 . The coupling part 19 has an internally splined end portion 20 which fits to an externally splined blocking portion 21 of the drive tool 3 through a ring 22 . The blocking portion 21 is freely rotatable with respect to the housing 4 such that an operator can position the housing 4 at any desired orientation with respect to the bending plane . This facilitates to operate the handheld bending device 1 in a small operating space in a flexible manner .

[0036] The ring 22 has internal and external splines . This means that rotation of the blocking portion 21 with respect to the coupling part 19 is blocked . Opposite to the internally splined end portion 20 the coupling part 19 has an elongate plate 23 which extends parallel to the spindle nut 8 . The plate 23 is provided with pins 24 which proj ect from the plate 23 in a direction away from the drive tool 3 . The pins 24 fit in cooperating arcuate slot holes 25 of the spindle nut 8 such that the pins 24 can be easily inserted into the slot holes 25 and the coupling part 19 can rotate with respect to the spindle nut 8 within a predefined angle , for example 60 ° . This means that rotation of the blocking portion 21 of the drive tool 3 and the coupling part 19 with respect to the spindle nut 8 is blocked outside the predefined angle . Under operating conditions the drive tool 3 drives the spindle 7 in order to move the spindle nut 8 along the spindle 7 and bend the power cable 2 through the central bending part 9 and the side bending parts 11 . This means that the drive shaft 5 exerts a torque onto the spindle 7 . As a consequence , a reaction torque is exerted onto the blocking portion 21 of the drive tool 21 through the side bending parts 11 , the bars 18 , the spindle nut 8 , the pins 24 , the plate 23 , the splined end portion 20 of the coupling part 19 and the ring 22 . Since the drive shaft 5 and the blocking portion 21 are rotatable with respect to each other the action torque and reaction torque are balanced such that the operator who holds the housing 4 of the drive tool 3 does not feel the reaction torque . The housing 4 is rotatable with respect to the blocking portion 21 in this case , but they may be fixed to each other in an alterative embodiment .

[0037] In practice the handheld bending device 1 may be operated as follows . An operator can first place the central bending part 9 and the side bending parts 11 together with the spindle 7 and the spindle nut 8 onto a power cable 2 to be bent or straightened . In a next step the coupling part 19 can be mounted to the spindle nut 8 by inserting the pins 24 into the corresponding slot holes 25 and coupling the intermediate part 6 to the spindle 4 . This action might require a small rotation of the coupling part 19 with respect to the spindle nut 8 which is allowed by the presence of the slot holes 25 . The coupling part 19 and the drive tool 3 may be connected to each other before or after the latter action .

[0038] As described hereinbefore , the housing 4 of the drive tool 3 has an L-shape . A first leg of the L-shape extends parallel to the drive shaft 5 , whereas a second leg lies in a plane which may be angled with the bending plane about the spindle axis , since the housing 4 is freely rotatable with respect to the blocking portion 21 of the drive tool 1 . The second leg is provided with a switch 26 for switching the drive tool 3 on and of f .

[0039] The handheld bending device 1 may be provided with a stop for automatically stopping a straightening action of a power cable 2 as soon as a maximum displacement of the spindle nut 8 along the spindle 4 has been reached . For example , the spindle 4 may be provided with an abutment which contacts the spindle nut 8 when the allowable maximum displacement is achieved .

[0040] The invention is not limited to the embodiment shown in the drawings and described hereinbefore , which may be varied in di f ferent manners within the scope of the claims and their technical equivalents .

Claims

CLAIMS1. A handheld bending device (1) for bending or straightening a power cable (2) , comprising a central bending part (9) including a contact surface (12) for contacting a power cable (2) , two side bending parts (11) including respective contact surfaces (13) for contacting a power cable (2) , wherein the contact surface (12) of the central bending part (9) is directed in opposite direction with respect to the contact surfaces (13) of the side bending parts (11) and lies between the contact surfaces (13) of the side bending parts (11) in a bending plane, a spindle (7) having a spindle axis and one end to which the central bending part (9) is mounted freely rotatable about the spindle axis and an opposite end for being drivably connected to a drive shaft (5) of a drive tool (3) , and a spindle nut (8) which is drivably mounted to the spindle (7) at a distance from the central bending part (9) and to which the side bending parts (11) are mounted.

2. A handheld bending device (1) according to claim1, wherein the side bending parts (11) are mounted to opposite portions of the spindle nut (8) at a distance from the spindle (7) through bars (18) .

3. A handheld bending device (1) according to claim2, wherein the bars (18) lie in the bending plane.

4. A handheld bending device (1) according to claim 2 or 3, wherein each of the bars (18) is pivotally mounted to the corresponding side bending part (11) .

5. A handheld bending device (1) according to any one of the preceding claims, wherein the spindle nut (8) is elongate in the bending plane in transverse direction of the spindle (7) .

6. A handheld bending device (1) according to claim 2 and 5, wherein the spindle nut (8) and the bars (18) form a U- shape .

7. A handheld bending device (1) according to claim 6, wherein the bars (18) are formed integrally with the spindle nut ( 8 ) .

8. A handheld bending device (1) according to any one of the preceding claims, wherein the handheld bending device (1) is provided with a coupling part (19) which is configured to bemounted to a blocking portion (21) of a drive tool (3) such that the coupling part (19) is blocked with respect to the blocking portion (21) about the spindle axis, which coupling part (19) is mounted or mountable to the spindle nut (8) such that rotation of the coupling part (19) with respect to the spindle nut (8) about the spindle axis is blocked or blocked outside a predefined angle between the coupling part (19) and the spindle nut ( 8 ) .

9. A handheld bending (1) device according to claim 8, wherein the predefined angle is 60°.

10. A handheld bending device (1) according to claim 8 or 9, wherein one of the coupling part (19) and the spindle nut (8) has pins (24) which fit in cooperating slot holes (25) in the other one of the coupling part (19) and the spindle nut (8) for allowing rotation of the coupling part (19) with respect to the spindle nut (8) , which slot holes (25) are located at opposite sides of the spindle (7) when the coupling part (19) is mounted to the spindle nut (8) .

11. A handheld bending device (1) according to any one of the preceding claims, wherein the handheld bending device (1) comprises a drive tool (3) including a housing (4) and a drive shaft (5) , which drive shaft (5) is drivable in rotational direction with respect to the housing (4) about a drive shaft axis, wherein the spindle (7) is drivably connected are connectable to the drive shaft (5) .

12. A handheld bending device (1) according to claim 8 and 11, wherein the drive tool (3) is provided with a blocking portion (21) which is mounted or mountable to the coupling part (19) such that the coupling part (19) is blocked with respect to the blocking portion (21) about the spindle axis.

13. A handheld bending device (1) according to claim 12, wherein the housing (4) is freely rotatable with respect to the blocking portion (21) about the drive shaft axis.

14. A handheld bending device (1) according to claim any one of the claims 11-13, wherein the drive shaft axis and the spindle axis coincide when the drive shaft (5) and the spindle (7) are drivably connected to each other.

15. A handheld bending device (1) according to any one of the claims 11-14, wherein the housing (4) has an L-shapeincluding a first leg which is directed in the same direction as the drive shaft (5) and a second leg which is provided with a switch (26) for switching the drive tool (3) on and off.

16. A handheld bending device (1) according to any one of the claims 11-15, wherein the contact surface (12) of the central bending part (9) is directed to the drive tool (3) .

17. A handheld bending device (1) according to any one of the preceding claims, wherein the central bending part (9) is releasably mounted to the spindle (7) .

18. A handheld bending device (1) according to any one of the preceding claims, wherein the side bending parts (11) are releasably mounted to the spindle nut (8) .

19. A handheld bending device (1) according to any one of the preceding claims, wherein the central bending part (9) is pivotally mounted to the spindle (7) .

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