TORQUE TOOL

Description

[0001] The invention relates to a torque tool, in particular a torque screwdriver, according to the features in the preamble of claim 1.

[0002] Torque tools, such as torque screwdrivers, are hand-operated tools used to apply a controlled torque to a workpiece, usually a screw or nut. Adjustable torque tools allow for the application of a defined tightening torque to ensure the necessary clamping force or assembly preload between the components being joined.

[0003] In torque screwdrivers, the release mechanism is usually housed in the handle. The handle also contains an adjustment device with a torque indicator. The desired torque is set by compressing a spring, which rotates the adjusting element, connected to an adjustment mechanism (usually a threaded spindle), relative to a fixed part of the handle.

[0004] Document WO 2011 / 005892 A1 shows a torque tool according to the preamble of claim 1.

[0005] An adjustable torque screwdriver is known from US Patent 9,421,675 B2. The set torque can be read from a display, which is designed as a scale or vernier.

[0006] According to German patent DE 20 2013 103 740 U1, a torque wrench with a torque indicator is considered state of the art. The torque wrench features a display for the set torque. This display comprises a digital counter with multiple digits linked via a gear mechanism. The digits are arranged in a housing that surrounds the handle. The gear's drive shaft passes through the gears on one side of the housing. To accommodate the digital counter, the housing must be made in two parts: an upper cover and a lower cover, which are opposite each other and attached to the handle of the torque wrench. This design could be improved in terms of both space efficiency and functionality.

[0007] Starting from the prior art, the invention is based on the objective of improving a torque tool, in particular a torque screwdriver, in terms of installation space, application technology and functionality.

[0008] The solution to this problem consists of a torque tool, in particular a torque screwdriver, according to claim 1.

[0009] Advantageous embodiments and further developments of the torque tool according to the invention are the subject of the dependent claims. Embodiments and modifications of features of the torque tool, which individually or in combination make the invention technically advantageous, are also apparent from the description and the accompanying drawings.

[0010] A torque tool according to the invention is, in particular, a torque screwdriver. The torque tool has a handle and an adjusting element rotatable about the longitudinal axis of the handle for setting a torque. A set torque or the set torque value is displayed and can be read through a viewing window. The display includes a digital counter with at least two digital counters.

[0011] According to the invention, the digit counter is arranged in a hollow cylindrical section of the handle. A viewing window is provided in this section, through which the torque setting is visible. The viewing window is formed by a recess or opening in the wall of the handle within the hollow cylindrical section. The digit counter has a passage in its central axis through which a shaft section is guided. A carrier disc, fixed in rotation within the handle, is integrated between two digit rollers. A switching wheel is rotatably associated with the carrier disc. The switching wheel has drive teeth and switching teeth. Each digit roller has an outer ring of digits, which comprises a first ring section with inner drive teeth and a second ring section with a switching element.The actuator has means for transmitting a rotary movement of the actuator, namely the digit roller arranged on the actuator side.

[0012] The torque tool according to the invention is improved in terms of installation space, application technology, and functionality. In the torque tool according to the invention, a compact digital counter with an internal gear chain is implemented in the handle. The digital counter is arranged in a hollow cylindrical section of the handle.

[0013] Preferably, the means for transmitting the rotary movement of the actuating body and the drive teeth of the first digit roller adjacent to the actuating body, i.e. the digit roller on the actuating body side, are permanently in engagement.

[0014] The actuator is permanently radially coupled to the first digit roller on the actuator side. This coupling is achieved via drive lugs on the actuator and the drive teeth on the first digit roller. The first digit roller displays the lowest setting value.

[0015] Through the permanent coupling, every rotational movement of the actuating element is transmitted to the first digit roller. On the opposite side, the first digit roller has a switching element. This is preferably an internal tooth segment. A carrier disc is located between two digit rollers, for example, the first digit roller on the actuating element side and the subsequent second digit roller. The carrier disc has an eccentric shaft journal on which the switching wheel is mounted or held. The carrier disc is rotationally fixed to the handle. For this purpose, the carrier disc has, in particular, a radial projection that engages in a groove- or slot-shaped recess on the inner circumference of the hollow cylindrical section. The switching wheel has drive teeth and switching teeth. The drive teeth mesh with the drive teeth of a digit roller.The switching gear interacts with the switching element of a digit wheel. The switching element, located on one side of the carrier disc, ensures that after each full rotation, the following digit wheel is incremented or decremented by one numerical value. At least two digit wheels are required for this operation. The system can be expanded by adding one digit wheel, one carrier disc, and one switching wheel, as needed and as required by the technical requirements. Since each digit wheel has a switching element, each full rotation of the preceding digit wheel changes the value of the following digit wheel by one digit. The number of switching elements determines how many times the following digit wheel advances per rotation. Therefore, the number of switching elements and the number of advances are directly proportional to each other.

[0016] The invention provides a torque tool, in particular a torque screwdriver, with a display in which the entire display system, including the digital counter, can be inserted into the handle as a single unit. This is done from the actuator side into the hollow cylindrical section of the handle. The digital counter and its components are mutually supported. The digital counter is supported within the handle by the rotationally fixed arrangement of the support discs. A shaft section is guided centrally through the digital counter and the passage located on its central axis. This particularly advantageous aspect of the torque tool according to the invention enables the connection or coupling of the actuator-side components of the torque tool and the output-side components of the torque tool, in particular the torque setting mechanism and an adjustment arrangement.

[0017] An advantageous embodiment provides that the carrier disc has a radial projection which extends into or engages a recess in the handle. In this way, a counter-bearing or support for the digital counter is achieved via the carrier disc.

[0018] A further particularly preferred embodiment provides that the actuating element has a nozzle with drivers which engage with the drive teeth of the digit roller on the actuating element side. Preferably, the drivers are arranged on the end face of the nozzle.

[0019] The shaft section guided through the central passage in the digit counter is preferably part of an adjustment shaft, which is part of an adjustment arrangement by which a comparison between the set value of a torque displayed by the digit counter and the release torque can be carried out.

[0020] A number wheel has a hub and a disc body arranged between the hub and the outer ring of numbers.

[0021] The gear wheel is mounted on a shaft journal that is eccentrically arranged on the carrier disc.

[0022] A carrier disc has a cup-shaped central section. A radial disc section extends concentrically around the central section. The ratchet wheel is arranged in a receptacle of the carrier disc, which is located in the area of ​​the outer circumference of the central section. The disc section has an opening in the area of ​​the receptacle. The ratchet wheel protrudes through this opening with its drive teeth partially engaged, so that the portion of the drive teeth facing the downstream digit roller engages with the drive teeth of the downstream digit roller.

[0023] The switching teeth are connected to the drive teeth at their end faces. The drive teeth have a certain number of teeth, and the switching teeth have a certain number of switching teeth, with the number of drive teeth being twice the number of switching teeth. The ratio of the number of drive teeth to the number of switching teeth is 2:1. Therefore, the number of drive teeth is twice the number of switching teeth.

[0024] The switching teeth are arranged on a pitch circle at an angle to each other, with each switching tooth being aligned with a drive tooth. A switching wheel with six drive teeth therefore has three switching teeth, arranged at an angle of 120° to each other.

[0025] A further practically advantageous embodiment of the digit-roll counter consists in the fact that each digit roll has an annular collar on the switching element side, which has a recess in the area of ​​the switching element. The annular collar covers the switching teeth of the toothed mechanism, except for one. The single protruding switching tooth interacts with the switching element of a digit roll. After each complete rotation of a digit roll, the protruding switching tooth is engaged by the switching element. The switching tooth is then rotated 120° further, so that the next switching tooth protrudes from the annular collar. With this further 120° rotation of the switching tooth, the subsequent digit roll is advanced by one counter.

[0026] While the first digit roller, driven by the actuating element, rotates, the ratchet wheel remains stationary until, after a complete revolution, the actuating element of the first digit roller engages with a tooth of the ratchet wheel, rotating it by a segment of a circle corresponding to one digit advance. The next digit roller is then advanced by one digit. During the first digit roller's further rotation, the continuous engagement between the ratchet wheel's drive teeth and the second digit roller prevents the second digit roller and any subsequent digit rollers from rotating. Only after the second digit roller has completed a full revolution is the third digit roller, following the second, advanced by one digit position.

[0027] The invention is described in more detail below with reference to the drawings. These show: Figure 1 shows a torque tool according to the invention in the form of a torque screwdriver in a side view; Figure 2 shows a longitudinal section through the representation of the Figure 1 along line AA; Figure 3, section A according to the representation of Figure 2 in enlarged view; Figure 4 a perspective view of the handle of the torque screwdriver; Figure 5 a first sectional view through the handle according to the illustration of Figure 4 Figure 6 shows a second sectional view through the handle according to the illustration of Figure 4 Figure 7 shows a front view of the handle from the actuator side, and Figure 8 shows detail B. Figure 7 in enlarged view; Figure 9 Components of the torque screwdriver in an exploded view; Figure 10 a section through the representation of the Figure 9along the line AD-AD; Figure 11 shows a section through the representation of the Figure 10 along the line AG-AG in a perspective view; Figure 12 shows a section through the representation of the Figure 10 along the line AF-AF in a perspective view; Figure 13 the digit rollers of a digit roller counter in a perspective view; Figure 14 a perspective view of an adjusting element of a torque screwdriver; Figure 15 a vertical section through a digit roller counter; Figure 16 the components of the digit roller counter according to the representation of Figure 15 in an expanded representation; Figure 17 a section through the representation of the Figure 3 along line UU; Figure 18 a section through the representation of the Figure 3along the lines TT; Figure 19 the components of a digit roller counter in a perspective exploded view; Figure 20 the components of the digit roller counter from another perspective and Figure 21 another perspective exploded view of the components of a digit roller counter.

[0028] Based on the Figures 1 to 21 A torque tool according to the invention in the form of a torque screwdriver 1 and components thereof are described.

[0029] The torque screwdriver 1 has a handle 2, a display 3 for a set torque, and an output shaft 4. Integrated into the handle 2 is an adjusting device 5 for setting a specific torque or a defined tightening torque. The adjusting device 5 comprises an adjusting mechanism, not described in detail here, with which the desired torque is set by compressing a compression spring 6.

[0030] The adjusting device 5 and its adjusting mechanism interact with an adjusting element 7 on the handle 2. The adjusting element 7 is rotatable relative to the handle 2 about its longitudinal axis L. The torque is adjusted by rotating the adjusting element 7 relative to the stationary part of the handle 2. To secure the set torque against unintentional adjustment, the adjusting element 7 is locked by a locking mechanism 8, which is actuated by a locking element 9.

[0031] The output shaft 4 of the torque screwdriver 1 is located at the end face of the handle 2. The output shaft 4 is designed to accept interchangeable insert tools. For the interchangeable use of different insert tools, the output shaft 4 is equipped with a dedicated holding system.

[0032] The display 3 for a set torque has a digital counter 10 with several digit rollers 11, 12, 13 arranged in series. In the embodiment shown here, a total of three digit rollers 11, 12, 13 are provided. The digital counter 10 is arranged in a hollow cylindrical section 14 of the handle 2. The wall 15 of the section 14 is pierced by a viewing window 16. A portion of the digital counter 10 and the set torque are visible through the viewing window 16.

[0033] The digital counter 10 has a passage 17 in its central axis ML. A shaft section 18 passes through the passage 17. The shaft section 18 is part of an adjustment shaft 19, which is part of an adjustment arrangement by which a comparison can be made between the torque setting value displayed by the digital counter 10 and the release torque.

[0034] The digit counter 10 and the components of the display 3 belonging to the digit counter 10, individually and in various combinations, are particularly evident in the Figure 13 as well as 15 to 21.

[0035] A digit roll 11, 12, 13 has an outer cylindrical digit ring 20 bearing digits. The digit ring 20 has a first ring section 21 with drive teeth 22 and a second ring section 23 with a switching element 24. The drive teeth 22 are arranged circumferentially on the inner circumference of the first ring section 21. The switching element 24 is formed by a single internally toothed tooth segment. On the side 25 of a digit roll 11, 12, 13 on which the switching element 24 is located, i.e., on the switching element side, each digit roll 11, 12, 13 has an annular collar 26 which has a recess 27 in the area of ​​the switching element 24.

[0036] Each digit roller 11, 12, 13 has a hub 28 and a disk body 29 arranged between the hub 28 and the outer digit ring 20. A carrier disk 30, held rotationally fixed in the handle 2, is integrated between each pair of digit rollers 11, 12 or 12, 13. The carrier disk 30 has a radial projection 31 which engages in a recess 32 in the handle 2. The projection 31, extending into the recess 32, counteracts and prevents rotation of the carrier disk 30 in the handle 2.

[0037] Each carrier disk 30 is rotatably associated with a ratchet wheel 33. The ratchet wheel 33 is mounted on a shaft journal 34 arranged eccentrically on the carrier disk 30. The carrier disk 30 has a cup-shaped central section 35 with a radial disk section 36. The ratchet wheel 33 is arranged in a receptacle 37, which is located in the region of the outer circumference of the central section 35. In the region of the receptacle 37, the disk section 36 has an opening 38.

[0038] The gear 33 has a drive tooth 39 and a switching tooth 40. The switching tooth 40 abuts the drive tooth 39 at its end face. The drive tooth 39 has a number of drive teeth 41. The switching tooth 40 has a number of switching teeth 42. The number of drive teeth 41 is twice the number of switching teeth 42. In the example shown, there are a total of three switching teeth 42, arranged on a pitch circle at an angle of 120° to each other. Each switching tooth 42 is oriented congruently with each drive tooth 41.

[0039] The gear 33 sits in the receptacle 37 on the shaft journal 34. The drive teeth 39 are partially located in the opening 38, so that the drive teeth 39 protrude on both sides opposite the disc section 36.

[0040] The digit counter 10 is inserted as a unit from the opening 43 on the actuating element side into the handle 2 and positioned in the hollow cylindrical section 14. The shaft section 18 is guided through the passage 17. The projections 31 of the support disks 30 engage in abutting positions in the recesses 32 on the inner circumference of the section 14.

[0041] The actuator 7 has a nozzle 44. Drivers 45 are arranged on the end face of the nozzle 44. The drivers 45 are tooth-shaped and project outwards from an annular web 46 of the nozzle 44. Two drivers 45 are arranged close together around the circumference, forming a driver pair. Two pairs of drivers, each consisting of two drivers 45, are diametrically opposed to each other on the circumference of the annular web 46.

[0042] The drivers 45 of the actuating body 7 engage with the drive teeth 22 of the first digit roller 11 on the actuating body side. In this way, a rotary movement of the actuating body 7, by means of which an adjustment of the torque or release element is made, is transmitted directly to the first digit roller 11.

[0043] A carrier disk 30 is fixedly arranged between the first digit roll 11 and the second digit roll 12, and between the second digit roll 12 and the third digit roll 13. The first carrier disk 30, located between the first digit roll 11 and the second digit roll 12, transmits a rotational movement from the first digit roll 11 to the second digit roll 12. After a complete rotation of the first digit roll 11, the second digit roll 12 is rotated one digit or one position further. After the second digit roll 12 has completed a complete rotation, the subsequent third digit roll 13 is moved one digit or one position further.

[0044] The 40-tooth gear ratio is, as in the Figure 18The ring-shaped collar 26 overlaps the gear. Two adjacent switching teeth 42, arranged at an angle of 120° to each other, rest against the inside of the collar 26. The collar 26 slides over the two switching teeth 42. The gear 33 remains stationary in this position until a number roller 11, 12, 13 with the switching element 24 and the recess 27 moves over a switching tooth 40. The gear 33 is then released and rotates one position or one digit further.

[0045] Since the ratchet wheel 33 engages with the drive teeth 39 in the drive teeth 22 of the subsequent second digit roll 12, the digit roll 12 is held in place by the ratchet wheel 33 while the first digit roll 11 is rotated. After a complete rotation of the first digit roll 11, the ratchet wheel 33 engages with the switching teeth 40, or a switching tooth 42, and the switching element 24. The ratchet wheel 33 is rotated one position further, and the digit roll 12 is advanced by one digit. Subsequently, the switching teeth 42 are again covered by the collar 26. The ratchet wheel 33 and the digit roll 12 are held in a fixed position until the switching element 24 engages with a switching tooth 42 again after another complete rotation, and the ratchet wheel 33 and the digit roll 12 are rotated one further position. Similarly, the third digit roll, 13, is then rotated by one further digit or position. Reference symbol:

[0046] 1 -Torque screwdriver 2 -Handle 3 -Display 4 -Output 5 -Adjusting device 6 -Compression spring 7 -Actuating element 8 -Locking mechanism 9 -Locking body 10 -Dial counter 11 -Dial 12 -Dial 13 -Dial 14 -Length section 15 -Wall 16 -Viewing window 17 -Passage 18 -Shaft section 19 -Adjusting shaft 20 -Dial ring 21 -First ring section 22 -Drive teeth 23 -Second ring section 24 -Switching element 25 -Side of 11, 12, 13 26 -Flange 27 -Recess 28 -Hub 29 -Disc body 30 -Carrier disc 31 -Protrusion 32 -Recess 33 -Switching wheel 34 - Shaft journal 35 - Center piece 36 - Disc section 37 - Mount 38 - Opening 39 - Drive tooth 40 - Shift tooth 41 - Drive tooth 42 - Shift tooth 43 - Opening 44 - Nozzle 45 - Driver 46 - Ring rib L - Longitudinal axis ML - Central axis

Claims

1. Torque tool, in particular torque screwdriver (1), with a handle (2) and a setting body (7), rotatable about the longitudinal axis (L) of the handle (2), for setting a torque, as well as a display (3) for a defined torque, which comprises a digit roller counter (10), wherein the digit roller counter (10) has at least two digit rollers (11, 12, 13), wherein the digit roller counter (10) is arranged in a hollow cylindrical longitudinal section (14) of the handle (2), which has a viewing window (16) through which the set torque is visible, and the digit roller counter (10) has a passage (17) in its central axis (ML) through which a shaft section (18) is guided, characterised in that a carrier disc (30), arranged in the handle (2) in a rotationally fixed manner, is integrated between two digit rollers (11, 12 or 12, 13) and a control gear (33) is rotatably associated with the carrier disc (30), which has a drive toothing (39) and a control toothing (40), and wherein a digit roller (11, 12, 13) has an outer digit rim (20), which has a first rim section (21) with a drive toothing (22) as well as a second rim section (23) with a control element (24), and wherein the setting body (7) has means for transmitting a rotary movement of the setting body (7) to the digit roller (11), arranged on the setting body side.

2. Torque tool according to claim 1, characterised in that the carrier disc (30) has a radial projection (31), which projects into a recess (32) in the handle (2).

3. Torque tool according to claim 1 or 2, characterised in that the setting body (7) has a connecting piece (44) with drivers (45), which engage with the drive toothing (22) of the digit roller (11) on the setting body side.

4. Torque tool according to any one of claims 1 to 3, characterised in that the shaft section (18) is part of an adjusting shaft (19), which is a component of an adjusting arrangement by means of which a comparison can be made between the setting value of a torque indicated by the digit roller counter (10) and the triggering torque.

5. Torque tool according to any one of claims 1 to 4, characterised in that each digit roller (11, 12, 13) has a hub (28) and a disc body (29) arranged between the hub (28) and the digit rim (20).

6. Torque tool according to any one of claims 1 to 5, characterised in that the control gear (33) is mounted on a shaft journal (34), arranged eccentrically on the carrier disc (30).

7. Torque tool according to any one of claims 1 to 6, characterised in that the carrier disc (30) has a pot-shaped central piece (35) with a radial disc section (36), wherein the control gear (33) is arranged in a receiving element (37), which is arranged in the region of the outer circumference of the central piece (35), and the disc section (36) has an opening (38) in the region of the receiving element (37).

8. Torque tool according to any one of claims 1 to 7, characterised in that the control toothing (40) adjoins the drive toothing (39) on the front face, wherein the drive toothing (39) has a number of drive teeth (41) and the control toothing (40) has a number of control teeth (42), wherein the number of drive teeth (41) is twice as great as the number of control teeth (42), wherein the control teeth (42) are arranged on a pitch circle at an angle to one another and each control tooth (42) is oriented to be congruent with a driving tooth (41).

9. Torque tool according to any one of claims 1 to 8, characterised in that a digit roller (11) has an annular collar (26) on the control element side, which has a recess (27) in the region of the control element (24).