EP2774724A1 - Torque tool with release mechanism - Google Patents

Abstract

The torque tool (10) comprises a lever housing (12) having a handle portion (14) and a head portion (16) for transmitting a torque to a workpiece. A lever arrangement (18) for transmitting torque is arranged in the lever housing. The two release levers (20) are mounted on bearing bolts (22) pivotally mounted in the lever housing. The release levers each form a switching edge, through which a tool main portion is triggered. A pair of bearing pin for coarse and fine adjustments of a distance is mounted eccentrically.

Description

Technical area

1. a) das Drehmomentwerkzeug ein Hebelgehäuse mit einem Griffbereich und einem Kopfbereich zur Übertragung eines Drehmoments auf ein Werkstück aufweist,
2. b) in dem Hebelgehäuse eine Hebelanordnung zur Übertragung des Drehmoments angeordnet ist und
3. c) zwei Hebel über Lagerbolzen schwenkbar in dem Hebelgehäuse gelagert sind,
4. d) die zwei Auslösehebel jeweils eine Schaltkante ausbilden, über die das Drehmomentwerkzeug auslöst.

The invention relates to a torque tool with a triggering via a switching edge, wherein

1. a) the torque tool has a lever housing with a gripping area and a head area for transmitting a torque to a workpiece,
2. b) a lever arrangement for transmitting the torque is arranged in the lever housing and
3. c) two levers are mounted pivotably in the lever housing via bearing bolts,
4. d) the two release levers each form a switching edge over which triggers the torque tool.

description

The screw connection is the most commonly used connection in mechanical engineering. Such fasteners can only be effective through the use of suitable assembly tools. Among the suitable assembly tools include torque tools, as mentioned above. Torque tools are needed to apply a specific torque to a workpiece. Torque tools such as torque wrench or torque screwdrivers are known. There are particular indicating and triggering torque wrenches. Indicating torque tools always indicate the respective applied torque. With triggering torque tools, a setpoint torque is set. Once this torque is achieved when tightening a screw, the torque tool signals the achievement of the desired torque to a user. This can be signaled, for example, by an audible click or a noticeable click through power interruption.

The torque to be transmitted when using hand-guided tools depends on the physical constitution of the user as well as on his subjective sense of strength. Torque tools are used to load a bolt with a high preload force that is within the elastic range of the bolt or also to load the bolt with only slight preload forces. The use of new construction materials such as magnesium, aluminum or plastic, especially for lightweight construction in the automotive or aircraft industry can increase both the demand, as well as the requirements of the torque tools. These new materials increase the number of sensitive screw connections. The lower tensile strength of these lightweight materials compared to steel materials, would lead to damage the thread in an overuse of the screw, which would make these expensive components unusable.

State of the art

From the German patent application DE 100 51 011 A1 is a triggering torque wrench known which detects the torque electronically. With a strain gauge, the mechanical torque is converted into an electronic signal. The torque detected in this way is compared with a desired value. If the measured torque reaches the set or preset torque setpoint, the torque wrench is released mechanically at least temporarily by the electronic evaluation. The release takes place here for example by decoupling of the key handle and key head. The document proposes that the coupling is designed as a magnetic coupling with electric magnets, in which the magnets are switched off for decoupling. Alternatively, a plug-in element in a corresponding connector connects the key head with the key handle. By magnetic force, the rigid coupling is released by the connector, so that the key head can swing away.

In the German patent DE 199 12 837 C2 Also described is an electronically measuring and triggering torque wrench. In this torque wrench, a torque sensor detects the applied torque. Finally, a control device compares the measured actual value with a setpoint value, the setpoint value resulting from an analysis of the respective workpiece. The analysis of the workpiece is carried out directly by means of a workpiece identification device. If the actual value reaches the specified setpoint, the torque bowl is triggered.

The DE 3933913 A1 relates to a torque wrench, with a key body, a key shank and a transmission element, wherein a torque from the key body to the key shaft by means of the transmission element is transferable and the transmission element is movable at a defined load exceeding force from a transmission position to an overload position, in which a Relative movement between the key body and the key shank is enabled. Such a torque wrench is known, wherein designed as a rotary handle key body is associated with a ball bearing, relative to the key body radially movable key shank.

The DE 102004043217 A1 discloses a torque wrench with a handle and a tool holder and a display device for representing the reaching or exceeding of a preset torque, wherein the display device is composed of light-emitting elements, such as light-emitting diodes having a specific light indicator. To further improve a torque wrench of the type in question, in particular with regard to the visualization of the load condition of the torque wrench and thus also in terms of handling, there is proposed that the display device consists of a plurality of band or line-like arranged lighting elements and that the light display of a certain, often repetitive light pattern consists, which is achieved by a passage of the light elements.

From the DE 102006013147 A1 For example, a torque tool is known for measuring and / or triggering torque on a workpiece. The torque tool includes a housing with a handle and a rod for transmitting the torque. A measuring element is used for the electronic detection of the torque, which is processed by a measuring and control electronics torque. A trigger switch controlled by the electronic measuring and control electronics triggers the torque tool at a setpoint. The torque wrench described therein has a reduction mechanism which has at least one actuator actuated by the release switch. In this case, the reduction mechanism between the rod for transmitting the torque and the electronically controlled release switch for triggering the torque tool is arranged. This document describes that the reduction mechanism includes a shift lever with a shift edge controlled by the electronically controlled release switch.

Disadvantage of the known torque tools is that their production is very time consuming. Because every part, especially in the case of mechanical reductions, has to be specially measured, sorted and finally in a certain constellation be mounted so that the torque tool also triggers later at the actual set torque.

Disclosure of the invention

The object of the invention is therefore to avoid in particular the disadvantages of the prior art and to create a triggering torque wrench, no longer need to be time consuming measured in the production, sorted and mounted in a particular constellation. It is another object of the invention to provide a user-friendly torque tool.

• e) einer der Lagerbolzen zum Einstellen des Abstands zwischen den beiden Lagerbolzen exzentrisch gelagert ist.

According to the invention the object is achieved by a triggering torque tool of the type mentioned, in which

• e) one of the bearing pins is eccentrically mounted for adjusting the distance between the two bearing pins.

Due to the eccentric mounting of at least one bearing pin, the distance to the other bearing pin can be varied by being simply rotated for adjustment. After adjustment, the position of the bearing pin is fixed. Thus, the pivotally mounted on the bearing pin trigger lever is moved accordingly, so that the overlap of the switching edge can be adjusted to the attacking switching edge of the other trigger lever. The switching edge can in principle also be formed by a tilting cube or a toggle lever, which trigger the torque tool via its edge. The position of the release levers can be optimized with their switching edge The advantage that results from the adjustability is that the release levers no longer need to be processed so precisely. This saves time and money in the production. Likewise, there is no sorting according to certain criteria in order to select the right and matching release levers. Because the release lever can be readjusted if necessary.

In a preferred embodiment of the torque tool according to the invention two bearing pins for adjusting the distance are mounted eccentrically. This measure serves to ensure that each bearing pin can be adjusted with a release lever via the eccentric bearing. As a result, the distances between the bearing bolts can be realized larger or smaller than would be possible with a single eccentric bearing of a bearing pin.

Preferably, in an embodiment of the torque tool according to the invention an eccentric bearing of a bearing pin for coarse adjustment and an eccentric bearing of a bearing pin is designed for fine adjustment. The axes of the eccentric are at different radii of the bearing bolts. This ensures that the one bearing pin whose axis is on the smaller radius, used for fine adjustment and the other bearing pin whose axis is on the larger radius, used for coarse adjustment. This allows the measuring tool to be adjusted particularly well and precisely.

In a further advantageous embodiment of the torque tool according to the invention, an adjustment mechanism for adjusting the triggering torque is provided. The adjustment mechanism serves to carry out the respectively required setpoint torque on the torque tool. The torque tool then triggers at this set target torque. The adjustment mechanism thus causes the torque tool not only triggers at a fixed torque, but can be set variably.

Preferably, a locking mechanism for fixing the set release torque is provided on the adjustment mechanism. So that a set target torque for the release can not be adjusted, the locking mechanism is provided for this purpose. The locking mechanism blocks the accidental adjustment of the set target torque. The locking can be realized for example with a fixing screw, which permanently detects the adjustment mechanism in a set position until the fixing screw is released again. Then, by means of adjustment mechanism, a new setpoint torque can be set at which the torque tool is to trigger.

In a further variant of the torque tool according to the invention, the locking mechanism is spring-loaded. This has the advantage that the locking mechanism is biased. The locking mechanism triggers, for example, by being actuated against the spring force by actuation of a pin or a push button or lever. This happens faster than e.g. with a screw, which must first pass through a thread pitch until it either releases or locks the locking mechanism, as the case may be.

A preferred variant of the torque tool according to the invention is that the locking mechanism has a latching mechanism. For locking, for example, a pin or lever engages in the locking mechanism. Accordingly, to release the pin or the lever is removed again from the locking mechanism. The locking mechanism may include a bore or other profile recesses, in which engage the pin or the lever or a ball spring loaded.

A further preferred embodiment of the invention is that the adjusting mechanism of the torque tool has a slide which is guided in a slot gate. The slider is preferably mounted externally on the lever housing so that it can be conveniently operated by a user to set the desired torque. The slider may have a mark, which points to a scale. The scale displays torque values. Depending on where the slider is, the marker points to a different torque. By means of the locking mechanism, the slider can be found in the slot gate.

Further advantages and refinements emerge from the subject matter of the subclaims, as well as the drawings with the associated descriptions. Hereinafter, embodiments and details will be described with reference to the figures.

Short description of the drawing

Fig. 1

shows a schematic diagram of a torque wrench according to the invention in longitudinal section.

Fig. 2a

shows a schematic schematic diagram of a portion of the torque wrench according to the invention with the trigger mechanism in a longitudinal section.

Fig. 2b

schematically shows the switching edge region of the trigger mechanism in an enlargement.

Fig. 3

shows a section of the torque wrench according to the invention in the region of the trigger mechanism.

Fig. 4

shows a section AA according to the Figures 3 ,

Fig. 5

schematically shows a section of an eccentrically mounted bearing pin.

Fig. 6

shows a bearing pin for a torque wrench according to the invention.

Fig. 7

shows schematically the torque wrench without housing according to the invention in a plan view with a locking and adjusting mechanism.

Fig. 8

schematically shows the torque wrench without housing according to the invention in a side view with a locking and adjusting mechanism.

Fig. 9

shows a more detailed section of the torque wrench without housing in the region of the locking mechanism for the slide.

Preferred embodiment

In Fig. 1 is designated 10 an inventive triggering torque tool. It is a torque wrench 10, which is shown in a schematic schematic diagram in longitudinal section. The torque wrench 10 includes a shaft-like lever housing 12 having a handle portion 14 and a head portion 16 for transmitting torque to a workpiece. This head portion 16 usually consists of a drive head 17, which can accommodate for coupling with a workpiece, such as a screw, a plug-in or Aufsteckwerkzeug. The drive head 17 may include a ratchet mechanism to facilitate tightening a screw to the desired torque for a user.

In the lever housing 12, a lever assembly 18 is further arranged for transmitting the torque to the drive head 17. In this case, levers 20 are pivotally mounted via bearing pins 22 in the lever housing 12 in a mounting frame 23. The bearing pins 22 are arranged substantially parallel and provided transversely to the longitudinal axis of the lever housing 12. A trigger mechanism 24 is used to trigger the torque wrench 10. The trigger mechanism 24 includes two trigger levers 26, 28, which are also part of the lever assembly 18. Release lever 26, 28 each have a switching edge 30, 32, over which the torque wrench 10 triggers.

Fig. 2a shows in a longitudinal section the area of the torque wrench 10 where the triggering mechanism 24 is arranged. The release levers 26, 28 are pivotally mounted in the lever housing 12 each about their bearing pin 22. In the illustration, the switching edges 30, 32 of the release lever 26, 28 are clearly visible. The trigger lever 28 consists of two components, namely switching edge lever 34 and lever 36. In this case, the switching edge lever 34 is pivotally mounted on the adjusting lever 36 via a bearing pin 38. On a front side of the switching edge lever 34, the switching edge 32 is provided. The release lever 28 is biased by a bow spring 40. The adjusting lever 36 is pivotally mounted in the lever housing via an eccentrically mounted bearing pin 42. In this case, the bearing pin 42 with Snap rings 44 fixed. The trigger lever 26 has the switching edge 30. The switching edge 30 of the release lever 26 is in contact with the switching edge 32 of the release lever 28. In this case, the release lever 26 is pivotally mounted about the bearing pin 46. By turning the bearing pin 42, the adjusting lever 36 is changed in its position. The distance between the bearing pin 42 and the bearing pin 46 can be varied. The overlapping contact surfaces of the switching edges 30, 32 can thus be adjusted in the switching edge region 48 of the triggering mechanism in a suitable manner. Further levers or reduction lever 20 for torque transmission are indicated in the illustration. These levers are also pivotally mounted with bearing pin 22 in the lever housing 12.

Fig. 2b therefore shows the switching edge region 48 of the triggering mechanism 24 in an enlargement. In this switching edge region 48 overlap the switching edges 30, 32. The overlap region 50 of both switching edges 30, 32 is formed via the eccentrically mounted lever 36 adjustable. The switching edge lever 34 is pivotally mounted on the adjusting lever 36 via the bearing pin 38. The bow spring 40 holds the construction of the trigger mechanism 24 under sufficient tension.

Fig. 3 shows a section of the torque wrench 10 according to the invention in the region of the trigger mechanism 24. In this view, the lever assembly 18 with the trigger mechanism 24 within the lever housing 12 is not visible. The bearing pin 42 is mounted eccentrically. By means of a gear 51 designed as a toothing, which is arranged on the bearing pin 42, a latching mechanism 52 is formed. The locking mechanism 52 serves to fix the eccentrically mounted bearing pin 42 in a set position. As a result, the distance between the two bearing pins 42 and 46 can be varied. The end of the one trigger lever 26 and the release lever 28 can also be seen.

Fig. 4 shows the detail of the torque wrench 10 according to the invention in the region of the trigger mechanism 24 according to FIG. 2 in a section AA according to the FIG. 3 , The bearing pin 42 is mounted eccentrically in the housing 12. The bearing pin 42 is secured to the snap ring 44. About Innenmitnahme 53 of the gear 51, the locking mechanism 52 is actuated for adjusting the bearing pin 42.

Due to the eccentric mounting of the bearing pin 42, the position of the release lever 28 can be moved. Thus, the switching edge 32 of the switching edge lever 34 relative to the switching edge 30 of the trigger lever 26 is moved accordingly. The overlap of the switching edge 30 with the switching edge 32 takes place in the switching edge region 48. The switching edge lever 34 is pivotally mounted on the adjusting lever 36 by means of the bearing pin 38. The switching edge lever 34 forms with the adjusting lever 36, the release lever 28th

Fig. 5 schematically shows a section of an eccentrically mounted bearing pin 42. The gear 51 of the latching mechanism 52 is fixed to the bearing pin 42. In the lever housing 12 to a recess 54 is provided, which corresponds to the contours 56 of the gear 51. The bearing pin 42 is arranged eccentrically in the gear 51. The gear 51 is fixed in the contour 56 by the latching mechanism 52. The bearing pin 42 and the gear 51 can not rotate in this position. By slight axial displacement of the gear 51, the bearing pin 42 can rotate with the gear 51, since it is no longer in the toothing. The gear 51 is namely then outside the contour 56 of the latching mechanism 52 in the lever housing 12th

The release lever 28 is pivotally mounted on the eccentrically mounted bearing pin 42. By turning the bearing pin 42, the release lever 28 can be moved in its position. But this also allows the switching edge region 48 to be adjusted at the same time with the switching edges 30, 32 (cf. Fig. 2a or 2b). The bearing pin 42 is further fixed with the appropriate snap ring 44 in its bearing of the lever housing 12. In this figure, further levers 20 of the lever assembly 18 of the torque wrench 10 can be seen.

Fig. 6 shows in a schematic schematic diagram of the bearing pin 42 for the torque wrench 10 according to the invention. At one end face of the cylindrical bearing pin 42 is the gear 51 of the locking mechanism 52. At the other end of the bearing pin 42, a disc-like bearing support 58 is provided. The axis 60 of the bearing pin 42 is arranged eccentrically with respect to the disc-like bearing holder 58 and the gear 51. By turning the Whole construction, the bearing pin 42 moves eccentrically. This also moves the trigger lever 28 (see Fig. 2a ) corresponding to which is mounted pivotably about such a bearing pin 42.

Fig. 7 schematically shows the torque wrench 10 according to the invention without the lever housing 12 in a plan view with an adjustment mechanism 62. The adjustment mechanism 62 has a slider 64 on. The slider 64 is displaced in a slot slot 66 for setting a target torque. For this purpose, a support 71 acts via a guide 69 on a bending rod 70. The bending rod 70 is guided in the support 71. The flexure rod 70 is coupled to the triggering mechanism 24 via the lever assembly 18. By moving the support 71 on the guide 69 along the bending rod 70 at the same time change its bending properties, which can be set a different target torque. The support 71 is actuated via the slider 64. On the lever housing 12, a scale 68 is provided with torque values (see Figure 8 ). The slider 64 is moved in the slot gate 66 until a mark on the desired target torque of the scale 68 shows, ie at the torque at which the torque wrench finally trigger. A locking mechanism 72 fixes the slider 64 at the desired torque. The locking mechanism 72 may be formed as a screw, so that a certain position in the slot gate 66 can be fixed.

Preferably, as shown in this embodiment, a spring-loaded locking lever 74 may be used instead of the screw. The locking lever 74 has a latching nose 75. This spring-loaded latching lever 74 engages with its latching nose 75 in a latching mechanism 76 a. This fixes a set target torque. The locking lever 74 is in this case actuated via the slider 64. The slider 64 has an actuating pin 78 which moves the locking lever 74. By pressing a button 80 of the slider 64 of the actuating pin 78 and thus the locking lever 74 is released from the grid of the locking mechanism 76 and can be moved. The actuating pin 78 presses the locking lever 74 against the spring force of spring 79 from the locking mechanism 76. The locking lever 74 is pivotally mounted for this purpose. Letting go of the slider 64 causes the locking lever 74 with its locking lug 75 back into the Locking mechanism 76 engages. A set target torque can then no longer be adjusted.

Incidentally, the triggering mechanism 24 of the torque wrench 10 functions in the same manner as in the previously described figures. Both the triggering mechanism 24 and the lever assembly 18 are energized by the bow spring 40. Corresponding components are therefore also denoted by the corresponding reference numerals. The adjustability of the bearing pin 42 is provided in the embodiment thereof.

Fig. 8 shows the torque wrench 10 according to the invention Fig. 7 in another perspective view with the adjustment mechanism 62. The slider 64 is as long in the slot slot 66 of the lever housing or the mounting frame 23 is moved until a marker on the scale 68, the desired target torque for the release of the torque wrench 10 is set. The support 71 acts via the guide 69 on the bending rod 70, which is coupled via the lever assembly 18 with the trigger mechanism 24. By moving the support 71 along the bending rod 70 change bending properties of the bending rod 70, which in addition to the lever assembly 18 transmits the torque. The torque wrench 10 triggers at the set torque. As far as these FIG. 8 correspond to the previous figures, also here corresponding reference numerals are used. The spring-loaded locking lever 74 locks the slider 64 at a set target torque (see also Fig. 9 ). For this purpose, the pin 78 engages in the latching mechanism 76.

Corresponding to the previous figures shows Fig. 9 a more detailed section of the torque wrench 10 without lever housing 12 in the region of the locking mechanism 72 for the slider 64. The slider 64 can be moved in the slot slot 66 of the mounting frame 23 until the desired target torque for the release of the torque wrench 10 is set. The support 71 shortens or lengthens the effective range of the bending rod 70, whereby the target torque is set. The bending rod 70 is connected via the lever assembly 18 with the trigger mechanism 24, ie with the release levers 26, 28, in connection. The spring-loaded locking lever 74 locks the slider 64 at a set target torque. For this purpose, the locking lever 74 engages with its locking lug 75 positively or non-positively in a suitable latching structure, such as one or more profile notches, the latching mechanism 76 a.

reference numeral

10 torque wrench 12 lever housing 14 grip area 16 head area 17 powerhead 18 lever assembly 20 lever 22 bearing bolt 23 mounting frame 24 trigger mechanism 26 sear 28 sear 30 switching edge 32 switching edge 34 Switching edges lever 36 lever 38 bearing bolt 40 bow spring 42 bearing bolt 44 Snap rings 46 bearing bolt 48 Switching edge region 50 overlapping mechanism 51 gear 52 detent mechanism 53 interior entrainment 54 recess 56 contours 58 bearing support 60 axis 62 adjustment 64 pusher 66 Elongated slot 68 scale 69 guide 70 bending Beam 71 edition 72 locking mechanism 74 locking lever 75 locking lug 76 detent mechanism 78 actuating pin 79 feather 80 stud

Claims (8)

Torque tool (10) with a release via a switching edge (30, 32), wherein a) the torque tool (10) has a lever housing (12) with a gripping area (14) and a head area (16) for transmitting a torque to a workpiece, b) in the lever housing (12) has a lever arrangement (18) is arranged for transmitting the torque and c) two release levers (20) via bearing pins (22) are pivotally mounted in the lever housing (12) d) the two release levers each form a switching edge over which the torque tool triggers,
characterized in that e) one of the bearing pins (42) for adjusting the distance between the two bearing pins (42, 46) is mounted eccentrically. Torque tool (10) with a release via a switching edge (30, 32) according to claim 1, characterized in that both bearing pins (42, 46) are mounted eccentrically for adjusting the distance. Torque tool (10) with a release via a switching edge (30, 32) according to claim 2, characterized in that an eccentric bearing a bearing pin (46) for coarse adjustment and an eccentric bearing of a bearing pin (42) is designed for fine adjustment. Torque tool (10) with a release via a switching edge (30, 32) according to one of claims 1 to 3, characterized in that an adjustment mechanism is provided for adjusting the release torque. Torque tool (10) with a triggering via a switching edge (30, 32) according to claim 4, characterized in that a locking mechanism (72) for fixing the set triggering torque on the adjusting mechanism (62) is provided. Torque tool (10) with a release via a switching edge (30, 32) according to one of claims 4 or 5, characterized in that the locking mechanism (72) is designed to be spring-loaded. Torque tool (10) with a triggering via a switching edge (30, 32) according to one of claims 4 to 6, characterized in that the locking mechanism (72) has a latching mechanism (76). Torque tool (10) with a triggering via a switching edge (30, 32) according to one of claims 4 to 7, characterized in that the adjusting mechanism (62) has a slide (64) which is guided in a slot gate (66).

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