EP0532289A1 - A device for applying torque to a fastener - Google Patents
A device for applying torque to a fastener Download PDFInfo
- Publication number
- EP0532289A1 EP0532289A1 EP92308171A EP92308171A EP0532289A1 EP 0532289 A1 EP0532289 A1 EP 0532289A1 EP 92308171 A EP92308171 A EP 92308171A EP 92308171 A EP92308171 A EP 92308171A EP 0532289 A1 EP0532289 A1 EP 0532289A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- movable
- lost
- biasing means
- fastener
- recess
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B23/00—Details of, or accessories for, spanners, wrenches, screwdrivers
- B25B23/14—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers
- B25B23/141—Mechanical overload release couplings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
- B25B23/00—Details of, or accessories for, spanners, wrenches, screwdrivers
- B25B23/14—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers
- B25B23/142—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers
- B25B23/1422—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers torque indicators or adjustable torque limiters
- B25B23/1427—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers torque indicators or adjustable torque limiters by mechanical means
Definitions
- the invention relates to a device for applying torque to a fastener such as a screw or bolt.
- Conventional screw-drivers for applying a pre-determined torque level to a fastener generally comprises a coupling mechanism which includes one or more spherical balls which are located in close-fitting recesses and which are biased against a cam by means of a spring bias device.
- a coupling mechanism which includes one or more spherical balls which are located in close-fitting recesses and which are biased against a cam by means of a spring bias device.
- a device for applying torque to a fastener comprises a first member adapted to be coupled to a fastener and a second member coupled to the first member by a releasable coupling which transmits torque applied to the second member to the first member, and whereby the releasable coupling is adapted to de-couple the second member from the first member when the torque applied to the second member exceeds a predetermined magnitude, and the releasable coupling comprising a lost motion device to couple the second member to the first member.
- the lost motion device comprises a lost motion member and a movable member mounted on the lost motion member which is movable between an engaged position in which the second member is coupled to the first member and a disengaged position in which the second member is de-coupled from the first member.
- the lost motion member includes a recess and the dimensions of the movable member and recess are chosen to permit relative movement of the movable member in the recess, preferably in both a radial direction and a circumferential direction.
- the movable member comprises a spherical shaped member and the recess may be radially and circumferentially extending slots in which the spherical member moves.
- the releasable coupling further comprises biasing means and a counter-biasing means and the movable member is biased into engagement with the counter biasing means by the biasing means and typically, the biasing means may be adjustable in order to vary the biasing force applied to the movable member.
- the counter biasing means comprises a cam device.
- the movable member and the lost motion member move relative to the counter-biasing means.
- the counter-biasing means is mounted on the second member and the lost motion member and movable member are mounted on the first member.
- the first member may comprise a shaft of the screw-driver and the second member may comprise a handle.
- the releasable coupling comprises three recesses in the lost motion member and three corresponding movable members.
- the lost motion member and the movable members are mounted on the first member and the counter biasing means is mounted on the second member.
- the counter biasing means comprises a cam device, then this is in the form of a cam ring mounted on the second member.
- the biasing means comprises a helical spring and may further comprise a spherical member which transmits the biasing force from the spring to the movable member.
- the central axis of the spring is parallel to the central axis of the shaft of the screw-driver and typically, is coincident with the central axis of the shaft.
- loss motion device means a device which permits a limited movement of one member relative to the other member, without a corresponding movement of the other member.
- Fig 1 shows a screw-driver 20 which comprises a shaft 1 which is fixed to a spring housing 19 at one end. At the other end of the shaft 1 is 1 / 4 inch square drive 21 which has a blind bore 22 in which is mounted a steel ball 14 with a diameter of approximately 1 / 8 inch (3.175mm) and a spring 10 to bias the steel ball 14 towards the position shown in Fig 1. The ball 14 is retained by light deformation of the mouth of the bore 22.
- an adjusting screw 4 which is rotationally locked to the spring housing 19 by means of a nylon ball 17 which has a diameter of approximately 3/32 inch (2.38mm).
- a spring 6 is located within the spring housing 19 and abuts against the inner side of the adjusting screw 4 at one end and against a spring pad 16 at its other end.
- the spring pad 16 rests on a steel ball 12 of approximately 1 / 2 inch (12.7mm) diameter which transmits the biasing force from the spring 6 to three steel balls 13 (only one shown) which are mounted in apertures 23 in the spring housing 19.
- Each of the steel balls 13 has a diameter of approximately 7/32 inch (5.56mm).
- the spring housing 19 is mounted within a handle assembly which comprises a handle 3, a cam ring 2 mounted at the lower end of the handle 3.
- the handle 3 has an aperture 24 in its upper end which is screened by a threaded plug 9.
- the shaft 1 and spring housing 19 are rotationally mounted on the handle assembly by means of a radial bearing 15 mounted between the cam ring 2 and shaft 1 which is held in position by a retaining ring 11, and a thrust washer assembly which comprises two outer thrust washers 7 and a central thrust washer 8 which are located between the upper end of the spring housing 19 and the inside of the handle 3.
- the thrust washer assembly has a central aperture 25 which permits access to engagement recesses 26 in the adjusting screw 4.
- Fig 3 is a cross-sectional view through the spring housing 19 along the line AA in Fig 1, with the other components removed.
- FIG 3 there are 3 apertures 23 equi-spaced circumferentially around the spring housing 19.
- the centres of the apertures 23 are mutually spaced circumferentially by 120 o .
- each aperture 23 has a slot profile so that each steel ball 13 may move circumferentially, by about 40 o in the embodiment, within its corresponding aperture 23.
- Each ball 13 may also move radially within its respective aperture 23.
- Fig 4 is a cross-sectional view of the cam ring 2 also along the line AA in Fig 1 and with the other components omitted.
- the cam ring 2 has six recesses 24 formed in its internal surface 25.
- Each recess 24 is equi-spaced around the internal circumference of the surface 25 and so the centre of each recess 24 is mutually spaced from the other recesses 24 by 60 o .
- the other steel balls 13 are also located in their respective recesses 24.
- three recess mutually spaced by 120 o may be used.
- a fastener coupling (not shown) is attached to the square drive 21 of the shaft 1 and is engaged with a fastener, such as a screw or bolt (not shown).
- a fastener such as a screw or bolt (not shown).
- An operator then grips the handle 3 with his hand and applies a rotational torque to the handle 3.
- the spring 6 forces the steel balls 13 outwards via the spring pad 16 and the 1 / 2 inch steel ball 12, the steel balls 13 are forced into the recesses 24 in the cam ring 13.
- rotational movement of the handle 3 which rotates the cam ring 2, as the cam ring 2 is fixed to the handle 3, forces rotation of the steel balls 13 and hence rotation of the housing 19 and shaft 1. Therefore, the torque applied to the handle 3 by the operator is transmitted to the square drive 21 and the fastener in order to tighten or loosen the fastener.
- the threshold torque level of the screw-driver 20 may be increased or decreased as described by an appropriate choice of the strength of the spring 6.
- the threshold may be adjusted by removing the plug 9 and moving the adjustable screw 4 up or down the inside of the housing 19 by using an appropriate tool engaged with the recesses 26 though the aperture 25.
- the threshold is increased by compression of the spring 6 and decreased by allowing the spring to extend.
- Fig 5 illustrates possible cam profiles in detail.
- the recess 24 has a central radiused portion 30 of radius R1 bounded by two flat portions 31 which are each inclined at 45 o to the median plane.
- the radius R1 is slightly larger than the radius of the balls 13.
- the flat portions 31 join the inner cam face 32 via radiused portions 33 of radius R2. This cam profile is similar to that used in prior art screwdrivers.
- the recess 24 consists of a radiused portion 30 of radius R1 and the joining radiused portions 33 of radius R2, R2 suitably being equal to R2 of Fig. 5A and R1 being equal to the radius of the balls 13 .
- Fig 6 illustrates the form of the slots 23 in greater detail.
- the circumferential extent of each slot can be defined in terms of a nominal angle ⁇ between the centre of the ball when at its end positions. This dimension can also be defined in terms of the path length X taken along the mean diameter of the sleeve and expressed as a proportion of the ball diameter D.
- Table I summarises experiments carried out on different slot sizes, which indicate that longer slots are more effective in reducing reverse torque.
- the reverse torque figures in Table I are given for a spring setting for a nominal forward torque of 90 cN.m.
- This invention thus provides an improved torque-applying device which reduces the risk of reverse torque being inadvertently applied. It has also been found that the device of the invention reduces the risk of repetitive strain injury to the operator.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Details Of Spanners, Wrenches, And Screw Drivers And Accessories (AREA)
Abstract
A device for applying torque to a fastener, comprising a first member (1) adapted to be coupled to a fastener, and a second member (3) coupled to the first member (1) by a releasable coupling (2, 13, 19) adapted to transmit torque applied to the second member (3) to the first member (1) and to de-couple the second member (3) from the first member (1) when the torque applied to the second member (3) exceeds a predetermined magnitude; characterised in that the releasable coupling comprises a lost-motion device (2, 13, 19).
Description
- The invention relates to a device for applying torque to a fastener such as a screw or bolt.
- Conventional screw-drivers for applying a pre-determined torque level to a fastener, such as a screw or bolt, generally comprises a coupling mechanism which includes one or more spherical balls which are located in close-fitting recesses and which are biased against a cam by means of a spring bias device. When the torque applied through the handle of the screw-driver to the fastener exceeds a predetermined level, then the cam overcomes the biasing force of the biasing device and the balls are forced further into their recesses. This enables the balls to move relative to the cam and to de-couple the handle from the fastener.
- In accordance with the present invention, a device for applying torque to a fastener comprises a first member adapted to be coupled to a fastener and a second member coupled to the first member by a releasable coupling which transmits torque applied to the second member to the first member, and whereby the releasable coupling is adapted to de-couple the second member from the first member when the torque applied to the second member exceeds a predetermined magnitude, and the releasable coupling comprising a lost motion device to couple the second member to the first member. Preferably, the lost motion device comprises a lost motion member and a movable member mounted on the lost motion member which is movable between an engaged position in which the second member is coupled to the first member and a disengaged position in which the second member is de-coupled from the first member.
- Typically, the lost motion member includes a recess and the dimensions of the movable member and recess are chosen to permit relative movement of the movable member in the recess, preferably in both a radial direction and a circumferential direction. In the preferred embodiment, the movable member comprises a spherical shaped member and the recess may be radially and circumferentially extending slots in which the spherical member moves.
- Preferably, the releasable coupling further comprises biasing means and a counter-biasing means and the movable member is biased into engagement with the counter biasing means by the biasing means and typically, the biasing means may be adjustable in order to vary the biasing force applied to the movable member. In the preferred embodiment, the counter biasing means comprises a cam device.
- Preferably, when the movable member is in the disengaged position, the movable member and the lost motion member move relative to the counter-biasing means.
- In the preferred embodiment, the counter-biasing means is mounted on the second member and the lost motion member and movable member are mounted on the first member.
- Typically, where the device is a screw-driver the first member may comprise a shaft of the screw-driver and the second member may comprise a handle. Typically, in this example, the releasable coupling comprises three recesses in the lost motion member and three corresponding movable members. Preferably, the lost motion member and the movable members are mounted on the first member and the counter biasing means is mounted on the second member. Typically, where the counter biasing means comprises a cam device, then this is in the form of a cam ring mounted on the second member.
- Preferably, the biasing means comprises a helical spring and may further comprise a spherical member which transmits the biasing force from the spring to the movable member. Typically, where the device is a screw-driver and the biasing means is a helical spring, the central axis of the spring is parallel to the central axis of the shaft of the screw-driver and typically, is coincident with the central axis of the shaft.
- The term "lost motion device" as used herein means a device which permits a limited movement of one member relative to the other member, without a corresponding movement of the other member.
- An example of a device for applying torque to a fastener in accordance with the invention will now be described with reference to the accompanying drawings, in which:-
- Fig 1 is a cross-sectional view of a screw-driver;
- Fig 2 is an exploded perspective view of parts of the screwdriver of Fig 1;
- Fig 3 is a cross-sectional view through a spring housing for use with the screw-driver along the line AA in Fig 1 with the other components omitted;
- Fig 4 is a cross-sectional view through a cam ring for use with the screw-driver along the line AA in Fig 1 with the other components omitted;
- Figs 5A and 5B are detail views of parts of cam profiles which may be used; and
- Fig. 6 illustrates certain dimensions referred to in the description.
- Fig 1 shows a screw-
driver 20 which comprises a shaft 1 which is fixed to aspring housing 19 at one end. At the other end of the shaft 1 is 1/4 inchsquare drive 21 which has ablind bore 22 in which is mounted a steel ball 14 with a diameter of approximately 1/8 inch (3.175mm) and aspring 10 to bias the steel ball 14 towards the position shown in Fig 1. The ball 14 is retained by light deformation of the mouth of thebore 22. - Within the
spring housing 19 is located an adjusting screw 4 which is rotationally locked to thespring housing 19 by means of anylon ball 17 which has a diameter of approximately 3/32 inch (2.38mm). Aspring 6 is located within thespring housing 19 and abuts against the inner side of the adjusting screw 4 at one end and against aspring pad 16 at its other end. Thespring pad 16 rests on asteel ball 12 of approximately 1/2 inch (12.7mm) diameter which transmits the biasing force from thespring 6 to three steel balls 13 (only one shown) which are mounted inapertures 23 in thespring housing 19. Each of thesteel balls 13 has a diameter of approximately 7/32 inch (5.56mm). - The
spring housing 19 is mounted within a handle assembly which comprises a handle 3, acam ring 2 mounted at the lower end of the handle 3. The handle 3 has anaperture 24 in its upper end which is screened by a threadedplug 9. - The shaft 1 and
spring housing 19 are rotationally mounted on the handle assembly by means of a radial bearing 15 mounted between thecam ring 2 and shaft 1 which is held in position by aretaining ring 11, and a thrust washer assembly which comprises two outer thrust washers 7 and a central thrust washer 8 which are located between the upper end of thespring housing 19 and the inside of the handle 3. The thrust washer assembly has acentral aperture 25 which permits access toengagement recesses 26 in the adjusting screw 4. - Fig 3 is a cross-sectional view through the
spring housing 19 along the line AA in Fig 1, with the other components removed. As shown in Fig 3 there are 3apertures 23 equi-spaced circumferentially around thespring housing 19. Hence, the centres of theapertures 23 are mutually spaced circumferentially by 120o. As shown in Fig 3 eachaperture 23 has a slot profile so that eachsteel ball 13 may move circumferentially, by about 40o in the embodiment, within itscorresponding aperture 23. Eachball 13 may also move radially within itsrespective aperture 23. - Fig 4 is a cross-sectional view of the
cam ring 2 also along the line AA in Fig 1 and with the other components omitted. As shown in Fig 4 thecam ring 2 has sixrecesses 24 formed in itsinternal surface 25. Eachrecess 24 is equi-spaced around the internal circumference of thesurface 25 and so the centre of eachrecess 24 is mutually spaced from theother recesses 24 by 60o. Hence, when one of thesteel balls 13 is located in arecess 24 theother steel balls 13 are also located in theirrespective recesses 24. Alternatively, three recess mutually spaced by 120o may be used. - In use, a fastener coupling (not shown) is attached to the
square drive 21 of the shaft 1 and is engaged with a fastener, such as a screw or bolt (not shown). An operator then grips the handle 3 with his hand and applies a rotational torque to the handle 3. At this time thespring 6 forces thesteel balls 13 outwards via thespring pad 16 and the 1/2inch steel ball 12, thesteel balls 13 are forced into therecesses 24 in thecam ring 13. Hence, rotational movement of the handle 3 which rotates thecam ring 2, as thecam ring 2 is fixed to the handle 3, forces rotation of thesteel balls 13 and hence rotation of thehousing 19 and shaft 1. Therefore, the torque applied to the handle 3 by the operator is transmitted to thesquare drive 21 and the fastener in order to tighten or loosen the fastener. - When the torque applied by an operator to the handle 3 exceeds a pre-determined threshold level, then the side walls of the
recesses 24 apply sufficient biasing force against thesteel balls 13 to force thesteel balls 13 into theapertures 23 against the biasing force of thespring 6. Hence, thesteel balls 13 may move circumferentially relative to thecam ring 2 against theinternal surface 25 of thecam ring 2. Thus, when the torque applied by the operator to the handle 3 exceeds the predetermined threshold level, thespring housing 19 is rotationally de-coupled from the handle 3 and so the operator knows that a predetermined torque has been applied to the fastener. - With conventional torque limiting screw-drivers, continued rotation of the handle 3 causes the
steel balls 13 to re-engage in the nextavailable recess 24, and such re-engagement could theoretically cause the fastener to have a reverse torque applied to it. However, by use of theapertures 23 which permit circumferential movement of thesteel balls 13 relative to thespring housing 19 the likelihood of the theoretically possible reverse torque being applied to the fastener is eliminated, as the motion of the handle 3 when thesteel balls 13 re-engage therecesses 24 is lost by circumferential movement of thesteel balls 13 in theapertures 23. - The threshold torque level of the screw-
driver 20 may be increased or decreased as described by an appropriate choice of the strength of thespring 6. In addition, for any given spring the threshold may be adjusted by removing theplug 9 and moving the adjustable screw 4 up or down the inside of thehousing 19 by using an appropriate tool engaged with therecesses 26 though theaperture 25. The threshold is increased by compression of thespring 6 and decreased by allowing the spring to extend. - Fig 5 illustrates possible cam profiles in detail. In Fig 5A, the
recess 24 has a central radiusedportion 30 of radius R1 bounded by twoflat portions 31 which are each inclined at 45o to the median plane. The radius R1 is slightly larger than the radius of theballs 13. Theflat portions 31 join theinner cam face 32 viaradiused portions 33 of radius R2. This cam profile is similar to that used in prior art screwdrivers. - In the cam profile of Fig. 5B the
flat portions 31 are omitted. Therecess 24 consists of a radiusedportion 30 of radius R1 and the joiningradiused portions 33 of radius R2, R2 suitably being equal to R2 of Fig. 5A and R1 being equal to the radius of theballs 13 . We have established experimentally that the cam profile of Fig 5B gives better results (in terms of lower reverse torque) in the device of the present invention than that of Fig 5A. - Fig 6 illustrates the form of the
slots 23 in greater detail. The circumferential extent of each slot can be defined in terms of a nominal angle α between the centre of the ball when at its end positions. This dimension can also be defined in terms of the path length X taken along the mean diameter of the sleeve and expressed as a proportion of the ball diameter D. Table I summarises experiments carried out on different slot sizes, which indicate that longer slots are more effective in reducing reverse torque. The reverse torque figures in Table I are given for a spring setting for a nominal forward torque of 90 cN.m.TABLE I Nominal angle α Slot length X Typical reverse torque (cN.m) Cam of Fig 5A Cam of Fig 5B 0 D (circular hole) 63 26 10o 1.235D 83 85 20o 1.477 D 31 18 30o 1.710 D 15 10 40o 1.943D 12 n/d n/d = not detectable. - This invention thus provides an improved torque-applying device which reduces the risk of reverse torque being inadvertently applied. It has also been found that the device of the invention reduces the risk of repetitive strain injury to the operator.
Claims (15)
- A device for applying torque to a fastener, comprising a first member (1) adapted to be coupled to a fastener, and a second member (3) coupled to the first member (1) by a releasable coupling (2, 13, 19) adapted to transmit torque applied to the second member (3) to the first member (1) and to de-couple the second member (3) from the first member (1) when the torque applied to the second member (3) exceeds a predetermined magnitude; characterised in that the releasable coupling comprises a lost-motion device (2, 13, 19).
- A device according to Claim 1, in which the lost-motion device (2, 13, 19) comprises a lost-motion member (19) and a movable member (13) mounted on the lost-motion member (19), the movable member (13) being movable between an engaged position in which the second member (3) is coupled to the first member (1) and a disengaged position in which the second member (3) is de-coupled from the first member (1).
- A device according to Claim 1 or Claim 2, in which the lost-motion member (19) includes a recess (23), and the movable member (13) and the recess (23) are dimensioned to permit relative movement of the movable member (13) in the recess (23).
- A device according to Claim 3, in which the movable member (13) is relatively movable in the recess (23) both radially and circumferentially.
- A device according to Claim 3 or Claim 4, in which the movable member comprises a sphere (13) and the recess comprises a slot (23) within which the sphere (13) is movable.
- A device according to Claim 5, in which the slot (23) has a radial dimension in the range 1.2D to 2.0D, where D is the diameter of the sphere (13).
- A device according to Claim 6, in which said radial dimension is 1.943D.
- A device according to any of Claims 2 to 7, in which the releasable coupling (2, 13, 19) further includes biasing means (6, 12) and counter-biasing means (2), the biasing means (6, 12) acting to urge the movable member (13) into engagement with the counter-biasing means (2).
- A device according to Claim 8, in which the biasing means (6, 12) is adjustable to vary the biasing force applied to the movable member (13).
- A device according to Claim 8 or Claim 9, in which the counter-biasing means comprises a cam device (2).
- A device according to Claim 10, in which the cam device is in the form of a cam ring (2) secured to the second member (3), the lost-motion member (19) is mounted on the first member (1), and there are provided three movable members (13) housed in respective slots (23) in the lost-motion member (19).
- A device according to Claim 11, in which the biasing means comprises a coil spring (6) and thrust means (12) transmitting the thrust of the coil spring (6) to the three movable members (13).
- A device according to Claim 12, in which the thrust means is a ball (12).
- A device according to Claim 12 or Claim 13, in which the coil spring (6) is adjustable to vary the thrust on the movable members (13).
- A device according to any of Claims 11 to 14, the device being in the form of a screwdriver, the second member comprising a handle (3) for gripping and turning by an operator, the first member comprising a shaft (1) extending from the handle (3) for connection to a fastener, and the coil spring (6) being axially disposed within the handle (3).
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9119313 | 1991-09-10 | ||
GB919119313A GB9119313D0 (en) | 1991-09-10 | 1991-09-10 | A device for applying torque to a fastener |
GB919119890A GB9119890D0 (en) | 1991-09-18 | 1991-09-18 | A device for applying torque to a fastener |
GB9119890 | 1991-09-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0532289A1 true EP0532289A1 (en) | 1993-03-17 |
Family
ID=26299522
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP92308171A Withdrawn EP0532289A1 (en) | 1991-09-10 | 1992-09-09 | A device for applying torque to a fastener |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP0532289A1 (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0755754A1 (en) * | 1995-07-26 | 1997-01-29 | HILTI Aktiengesellschaft | Screw fastening device |
EP1477278A2 (en) * | 2003-05-10 | 2004-11-17 | Mhh Engineering Co Ltd | A Clutch Mechanism for a Torque Screwdriver |
DE10143181B4 (en) * | 2001-09-04 | 2005-03-03 | Willi Hahn Gmbh & Co. Kg | Device for limiting the torque that can be transmitted by a screwing tool |
CN102653084A (en) * | 2012-04-23 | 2012-09-05 | 中山市长富五金制品有限公司 | Novel torque wrench |
WO2015151096A1 (en) * | 2014-04-03 | 2015-10-08 | MIS Implants Technologies Ltd. | A rotatable fastening device with an integral torque limiter |
CN107584449A (en) * | 2017-09-26 | 2018-01-16 | 北京无线电测量研究所 | A kind of adjusting torque switching device for screwing up threaded connector |
US11311988B2 (en) * | 2018-08-16 | 2022-04-26 | Wen-Chin Kuo | Torque connector |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1569991A (en) * | 1968-04-23 | 1969-06-06 | ||
DE2819226A1 (en) * | 1978-05-02 | 1979-11-08 | Holland Letz Guenter | Screwdriver attachment for drill - has coiled spring of slip clutch connected at one end to external sliding cap |
DE3140288A1 (en) * | 1981-10-10 | 1983-04-28 | Saltus-Werk Max Forst GmbH & Co, 5650 Solingen | Self-releasing torque wrench |
-
1992
- 1992-09-09 EP EP92308171A patent/EP0532289A1/en not_active Withdrawn
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1569991A (en) * | 1968-04-23 | 1969-06-06 | ||
DE2819226A1 (en) * | 1978-05-02 | 1979-11-08 | Holland Letz Guenter | Screwdriver attachment for drill - has coiled spring of slip clutch connected at one end to external sliding cap |
DE3140288A1 (en) * | 1981-10-10 | 1983-04-28 | Saltus-Werk Max Forst GmbH & Co, 5650 Solingen | Self-releasing torque wrench |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0755754A1 (en) * | 1995-07-26 | 1997-01-29 | HILTI Aktiengesellschaft | Screw fastening device |
US5709275A (en) * | 1995-07-26 | 1998-01-20 | Hilti Aktiengesellschaft | Screw-driving tool |
DE10143181B4 (en) * | 2001-09-04 | 2005-03-03 | Willi Hahn Gmbh & Co. Kg | Device for limiting the torque that can be transmitted by a screwing tool |
EP1477278A2 (en) * | 2003-05-10 | 2004-11-17 | Mhh Engineering Co Ltd | A Clutch Mechanism for a Torque Screwdriver |
EP1477278A3 (en) * | 2003-05-10 | 2006-10-04 | Mhh Engineering Co Ltd | A Clutch Mechanism for a Torque Screwdriver |
CN102653084A (en) * | 2012-04-23 | 2012-09-05 | 中山市长富五金制品有限公司 | Novel torque wrench |
CN102653084B (en) * | 2012-04-23 | 2015-08-12 | 中山市长富五金制品有限公司 | A kind of New torque wrench |
WO2015151096A1 (en) * | 2014-04-03 | 2015-10-08 | MIS Implants Technologies Ltd. | A rotatable fastening device with an integral torque limiter |
CN107584449A (en) * | 2017-09-26 | 2018-01-16 | 北京无线电测量研究所 | A kind of adjusting torque switching device for screwing up threaded connector |
CN107584449B (en) * | 2017-09-26 | 2019-03-15 | 北京无线电测量研究所 | A kind of adjusting torque switching device for screwing up threaded connector |
US11311988B2 (en) * | 2018-08-16 | 2022-04-26 | Wen-Chin Kuo | Torque connector |
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