Hydraulic Torque Wrench
Patent Information
- Application Number
- JP2024535494
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2021-12-15
- Filing Date
- 2022-12-14
- Publication Date
- 2025-12-05
AI Technical Summary
Existing hydraulic torque wrenches require multiple components to be handled simultaneously for reversing the direction of rotation, leading to potential loss and misalignment issues, and necessitate a larger tool size for effective torque transmission.
A hydraulic torque wrench with a drive member featuring a retention mechanism that allows single-handed operation by transitioning between locked and unlocked states using a retractable pin and spline connection, reducing the number of loose parts and enhancing torque transmission efficiency.
Simplifies the process of changing drive members by minimizing loose parts, reducing the risk of loss and misalignment, and maintaining tool stability while optimizing size for torque transmission.
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Abstract
Description
[Technical field]
[0001] The present invention relates to a hydraulic torque wrench. [Background technology]
[0002] Torque wrenches, such as hydraulic torque wrenches, are well known in the art and are widely used, for example, to apply torque to nuts, bolts, or other fasteners.
[0003] Some hydraulic torque wrenches, such as the one disclosed in WO 2018 / 130854, include a head that includes a drive mechanism powered by a hydraulic fluid that drives a rotating object.
[0004] Atlas Copco, as well as other suppliers, offer hydraulic torque wrenches with a removable drive (typically a square drive, but different shaped drives may be used, e.g., hexagonal or socket drives). One or more drive sleeves may be used to aid in inserting and / or positioning the drive. One or more removable retainers may be used to hold the drive.
[0005] To reverse the direction of rotation, it is necessary to remove the square drive component and position it on the opposite side of the tool. When changing drive direction, the operator must simultaneously handle several components, particularly the wrench, the square drive (and socket), and one or more retainers. Retainers can easily be dropped and lost, potentially making the tool unsafe or unstable and resulting in other components becoming misaligned.
[0006] The inventors are aware of attempts to solve this problem, such as that suggested in WO 2015 / 021197, but these sacrifice a significant amount of the area used for torque transmission to the drive in order to lock the tool, thus requiring a larger drive to transmit the same amount of torque, resulting in an unnecessarily large tool. Summary of the Invention [Means for solving the problem]
[0007] According to a first aspect of the present invention, we have provided a hydraulic torque wrench comprising: Input for pressurized hydraulic fluid; Drive connector; a drive mechanism powered by hydraulic fluid introduced at the input and configured to rotatably drive the drive connector; A drive member for coupling to a rotated object by a hydraulic torque wrench, the drive member having a first portion for engaging a drive connector to be driven by the drive connector and a second portion arranged to couple to the rotated object. A hydraulic torque wrench comprising: The drive member includes a retention mechanism having two states; a first state prevents removal of the drive member from the drive connector and a second state allows removal of the drive member from the drive connector, and the retention mechanism remains coupled to the drive member in both the first and second states.
[0008] This therefore provides a hydraulic torque wrench that does not require the removal of a separate retaining member in order to change the drive member. Therefore, the user only needs to handle two loose items, making the procedure for changing the drive member easier. The user is less likely to drop one item than they are to drop two loose items.
[0009] The retention mechanism may include at least one retractable pin in the drive member, typically in a first portion thereof, which in a first state extends from the drive member into the drive connector and in a second state is retracted into the drive member.
[0010] The first portion of the drive member may have splines, and the drive connector may have splines complementary to those of the first portion of the drive member; so that the first portion of the drive member may engage the drive connector via a splined engagement. Pins may protrude from the splines of the drive member. In particular, where the splines of the drive member and the splines of the drive connector include ridges separated by grooves, each of the pins may protrude from the grooves to engage a ridge of the drive connector. This may therefore allow for a greater percentage of the engagement to be splined, allowing for a more reliable transmission of torque than if a particular length of engagement of the first portion of the head was used to lock the drive member in place.
[0011] The splines of the drive connector may be in the bores.
[0012] The first portion of the drive member may include an internal bore, typically cylindrical. Each of the pins may function in a pin bore in the drive member that communicates with the internal bore, such that each of the pins protrudes further into the internal bore in the second state than in the first state. There may be a spring in each pin bore tending to bias each of the pins toward the second state.
[0013] The first portion of the drive member may comprise an eccentric cam member rotatable coaxially with the internal bore within the internal bore and having a radius, the cam member having at least one wide portion and at least one narrow portion, each wide portion having a larger radius than each narrow portion, and in the first state, one wide portion engages each of the pins to urge the pins along the pin bore, and in the second state, one narrow portion engages each of the pins. Typically, the cam member may be elliptical, with the wide portion along the major axis of the ellipse and the narrow portion along the minor axis.
[0014] Each thin section may be provided with a recess for a pin; this may then provide positive feedback to the user that the thin section is engaging a pin.
[0015] The first portion of the drive member may further include a locking mechanism that allows transition from the first state to the second state only when unlocked. As such, the locking mechanism may include a button member slidable through the internal bore and fixed relative to the cam member. The button member may include at least one protrusion, each of which functions within two associated slots in the internal bore, an axial slot along the length of the internal bore and a circumferential slot about the inner circumference of the internal bore.
[0016] Thus, when each projection is within the axial slot, the button member may move axially along the internal bore but is prevented from rotating; typically this corresponds to each of the wide portions of the cam member engaging each of the pins, such that the cam member is prevented from rotating and the first portion is locked in the first condition.
[0017] However, when the button member is pressed so that each protrusion reaches the circumferential slot, the button member is allowed to rotate, which in turn causes the cam member to rotate, thereby allowing each thin portion to engage a respective pin, and therefore allowing the first portion to assume the second condition.
[0018] The locking mechanism may include a spring arranged to bias the button member axially away from each circumferential slot.
[0019] The second section may include a square, hexagonal or other drive for rotating objects.
[0020] Description of embodiments of the present invention will now be given, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]
[0021] [Figure 1] FIG. 1 shows a side view of a hydraulic torque wrench according to an embodiment of the present invention. [Diagram 2] FIG. 2 shows a perspective view of the lock button of FIG. [Diagram 3-6] 3 to 6 show a cross section taken along line AA in FIG. 1 with the square drive of FIG. 1 removed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] A hydraulic torque wrench 10 is shown in the accompanying drawings. The wrench 10 comprises a head 11 having a port 12 for hydraulic fluid. The head 11 contains a drive mechanism (mainly internal, but indicated at 13) which uses the pressure of pressurised hydraulic fluid at port 12 to rotate a drive member 1 which is in the form of a square drive which will be described in more detail below. This is then coupled to the item to be rotated (e.g. via a socket to a nut).
[0023] The drive member 1 is coupled to the head 11 via a drive connector 14 in the head 11. This can be seen in more detail in Figure 6 of the accompanying drawings and comprises a bore 21 having an internal spline 15 running along the length of the bore 21.
[0024] The drive member 1 can also be seen in more detail in Figure 6 of the accompanying drawings and comprises a first portion 16 which is generally cylindrical and has an external splined surface 17 for engaging the drive connector 14, and a second portion 18 which provides a square (or other suitable shaped) drive for turning an object to be rotated.
[0025] A locking mechanism 19 integral with the drive member 1 is provided for retaining the drive member 1 in the drive connector 14. The locking mechanism is provided in an internal bore 1A in the first section 16. Two radial pin bores 1B extend from the internal bore into the external splined surface 17, terminating in grooves between the ridges which form the splines.
[0026] Each of these pin bores 1B contains a pin 2. Each of the pins 2 has a head 2A at the end of the pin in the internal bore 1A that is wider than the rest of the pin. A spring 3 acts between a step in the pin bore 1B and the head 2A, and acts to bias each pin 2 into the internal bore 1A.
[0027] A button member 4 is also provided which is capable of sliding axially and rotating (in accordance with what is described below) within the internal bore 1A and is retained by a retaining screw 5 which functions in a through bore 4A in the button member 4 and is biased axially out of the internal bore 1A by a spring 6.
[0028] The button member 4 has a cam portion 4D of elliptical cross section, which is used to drive the pin 2 through the pin bore 1B. When the wide portion (major axis) of the ellipse is adjacent to the pin 2, the pin will be urged outwardly against the force of the spring 3 to extend outwardly from the external splined surface 17, whereas when the narrow portion (minor axis) of the ellipse is adjacent to the pin 2, the pin will be retracted by the force of the spring 3 from the external splined surface 17 into the internal bore 1A.
[0029] The button member also has a radial bore 4C which receives a dowel pin 7 which acts as a protrusion. The dowel pin 7 functions in a groove or slot 1D, 1E which extends along the internal bore 1A parallel to its length and includes an axially extending groove 1D which communicates with a circumferential groove 1E at the back of the internal bore 1A.
[0030] 3, when the pin 2 extends from the external splined surface 17, the locking mechanism is in a first state since the pin 2 engages one of the ridges forming the spline of the internal spline 15. Since the dowel pin 7 is in the axially extending portion of the groove 1D, it is not possible to remove the drive connector or rotate the button member.
[0031] To remove the drive member 1 from the drive connector 14, the button member 4 is pushed against the force of the spring 6. The dowel pin 7 moves down the axially extending portion of the groove 1D to the position shown in Figure 4 of the accompanying drawings. As rotation of the button member 4 has not yet occurred (not yet permitted by the action of the dowel pin 7 in the axially extending portion of the groove 1D), the pin 2 is still pushed outwardly by the cam portion 4D and is still engaged with the spline 15.
[0032] However, now the dowel pin 7 reaches the circumferential groove 1E, so now the button member 4 is able to rotate. As the button member 4 rotates (as shown in FIG. 5 of the accompanying drawings), the cam portion 4D also rotates, and the pin 2 is allowed to be retracted from the spline 15 by the spring 3.
[0033] 5, the pin 2 is fully retracted and the locking mechanism 19 is in the second position. Two holes or detents 4E are in the cam portion 4D which allow positive feedback to the user as the pin 2 "clicks" into the detents 4E in the second position.
[0034] It is then possible to remove the drive member 1 as shown in Figure 6 of the accompanying drawings. It should be noted that the drive connector 14 is symmetrical and therefore the drive member 1 can be inserted and secured from either end of the drive connector 14.
[0035] In the second position, the pin 2 remains stored in the pin bore 1B, meaning that there is no impediment to reinsertion of the drive member 1 into the drive connector 14. The procedure is then carried out in reverse; the button member 4 is rotated around the circumferential groove 1E and then "pops" out of the axially extending groove 1D due to the force of the spring 6.
[0036] The pins 2 each have small bores 2B perpendicular to their length into which an assembly pin can be inserted during assembly of the drive member 1; effectively, these hold the pins 2 until the button member 4 is in the internal bore 1A.
Claims
1. 1. A hydraulic torque wrench comprising: input for pressurized hydraulic fluid; Drive connector; a drive mechanism powered by hydraulic fluid introduced at said input and arranged to rotationally drive said drive connector; a drive member for coupling to a rotating object by the hydraulic torque wrench, the drive member having a first portion that engages the drive connector to be driven by the drive connector, and a second portion that is arranged to couple to the rotating object; A hydraulic torque wrench comprising: the drive member includes a retention mechanism having two states; a first state prevents removal of the drive member from the drive connector and a second state allows removal of the drive member from the drive connector, and the retention mechanism remains coupled to the drive member in both the first and second states; the retention mechanism includes at least one retractable pin in the drive member, the retractable pin extending from the drive member into the drive connector in the first state and retracted in the drive member in the second state; the first portion of the drive member has splines and the drive connector has splines complementary to those of the first portion of the drive member; and Each pin projects from the splines of the drive member.
2. 2. The hydraulic torque wrench of claim 1, wherein the splines of the drive member and the splines of the drive connector include ridges separated by grooves, and each of the pins protrudes from the grooves of the drive member to engage a ridge on the drive connector.
3. 3. The hydraulic torque wrench of claim 1, wherein the first portion of the drive member includes an internal bore.
4. 4. The hydraulic torque wrench of claim 3, wherein each of the pins functions within a pin bore in the drive member that communicates with the internal bore, such that each of the pins protrudes further into the internal bore in the second state than in the first state.
5. 5. A hydraulic torque wrench as defined in claim 4, further comprising a spring in each pin bore tending to bias each of the pins toward said second condition.
6. 5. The hydraulic torque wrench of claim 4, wherein the first portion of the drive member comprises an eccentric cam member having a radius and rotatable coaxially with the internal bore within the internal bore, the cam member having at least one wide portion and at least one narrow portion, each wide portion having a larger radius than each narrow portion, and wherein in the first state, one wide portion engages each of the pins to urge the pins along the pin bore, and in the second state, one narrow portion engages each of the pins.
7. 7. The hydraulic torque wrench of claim 6, wherein said cam member is oval.
8. 7. A hydraulic torque wrench as claimed in claim 6, wherein each narrowed portion is provided with a recess for a pin.
9. 3. The hydraulic torque wrench according to claim 1, wherein the first portion of the drive member is provided with a locking mechanism that allows transition from the first state to the second state only when the locking mechanism is unlocked.
10. 10. The hydraulic torque wrench of claim 9, wherein the locking mechanism comprises a button member slidable through the internal bore and fixed relative to the cam member.
11. 11. The hydraulic torque wrench of claim 10, wherein the button member includes at least one protrusion each functioning in two associated slots in the internal bore: an axial slot along the length of the internal bore and a circumferential slot about the inner periphery of the internal bore.
12. 12. The hydraulic torque wrench of claim 11, wherein the locking mechanism comprises a spring arranged to bias a button member axially away from each circumferential slot.
13. 3. A hydraulic torque wrench according to claim 1 or 2, wherein the second section comprises a square, hexagonal or other drive for rotating an object.