Patent Application
20240286253
Hydraulically driven ratcheting torque tools generate an accurate bolt load through the rotation of a fastener. Standard hydraulic torque tools sometimes utilize a reaction arm affixed to a housing of the tool. This arm provides a means of abutment so that the tool can generate a tightening force into the fastener and not simply rotate around the axis of the fastener. Alternatively, a reaction washer can be used to provide an abutment means for the tool, where the reaction washer is a component to the threaded fastener assembly. In particular, the reaction washer is placed directly below the nut or bolt head being subjected to the intended tightening force. Further, the reaction washer is connected to the tool housing.
However, the known tools can be inefficient to operate and require significant maintenance to keep them operational. Further, they can be heavy and unwieldy to operate. In view of the above difficulties, a better tool is needed.
In view of the foregoing, a limited clearance hydraulic tool provides torque to an associated threaded fastener assembly. The limited clearance hydraulic tool includes a housing that receives hydraulic fluid and defines a piston cylinder. The piston cylinder defines a cylinder axis. The limited clearance hydraulic tool also includes a piston slidingly disposed within the piston cylinder of the housing that outputs force and travels between a retracted position and an extended position and a rachet wheel rotatably received in the housing. The rachet wheel defines a rachet axis and is configured to engage the associated threaded fastener assembly. The limited clearance hydraulic tool also includes a drive plate disposed within the housing so as to at least partially radially surround the rachet wheel and a piston rod extending between the drive plate and the piston.
The limited clearance hydraulic tool further includes a connection pin that defines a first point of contact between the piston rod and the drive plate. The connection pin continuously connects the piston rod and the drive plate together to always drive and retract the drive plate by transmitting the force from the piston to the drive plate. Additionally, the limited clearance hydraulic tool includes a push plate that defines a second point of contact between the piston rod and the drive plate. The push plate is separate and unique from the first point of contact. The push plate selectively connects the piston rod and the drive plate together for driving the drive plate.
It should, of course, be understood that the description and drawings herein are merely illustrative and that various modifications and changes can be made in the structures disclosed without departing from the present disclosure. Referring now to the drawings, wherein like numerals refer to like parts throughout the several views,
The limited clearance hydraulic tool 10 provides torque to an associated threaded fastener assembly 12 (
Initially, it is instructive to review the components of the associated threaded fastener assembly 12 to which the limited clearance hydraulic tool 10 engages to perform work. As illustrated in
The reaction washer 58 can slidingly and coaxially receive the threaded portion 56 and the nut 62 can threadingly and coaxially receive the threaded portion 56, both along the rachet axis 22 when the limited clearance hydraulic tool 10 engages the associated threaded fastener assembly 12. As noted hereinbefore, the limited clearance hydraulic tool 10 can be utilized to tighten or loosen the associated threaded fastener assembly 12. As will be appreciated, this means that the nut 62 would travel along the threaded portion 56 toward the free end 56a of the threaded portion 56 when the associated threaded fastener assembly 12 is being loosened so that the nut 62 could be removed from the threaded portion 56 and the nut 62 would travel along the threaded portion 56 away from the free end 56a of the threaded portion 56 when the associated threaded portion 56 is being tightened so that the nut 62 cannot be removed from the threaded portion 56. Although not illustrated, it will be understood that an object (such as a machine housing 14) that is static with respect to the nut 62, either receives or is attached to the threaded portion 56 distal to the free end 56a so as to provide a surface to which the reaction washer 58 and the nut 62 can be tightened (i.e., preventing linear movement of the reaction washer 58 and the nut 62 along the rachet axis 22 away from the free end 56a).
Further, it is noted that the reaction washer 58 can be configured by various methods to prevent rotation thereof about the threaded portion 56 with respect to the object. These configurations could include, for example, protrusions, raised patterns, or serrations so as to provide a high friction element on the engagement face 58c of the reaction washer 58 that would face toward the object and away from the free end 56a. Thus, this high friction element of the engagement face 58c of the reaction washer 58 engages the object to help prevent rotation of the reaction washer 58 with respect to the threaded portion 56 or the nut 62. As will be described in more detail hereinafter, the limited clearance hydraulic tool 10 engages the reaction washer 58 so that the housing 14 of the reaction washer 58 remains stationary with respect to the reaction washer 58, and hence, the object.
With reference to
The housing 14 can at least partially contain the piston 16, the rachet wheel 18, the drive plate 26, and the piston rod 32. The housing 14 can be of mono-block construction that includes an integral receiving member 68 that is configured to engage the associated reaction washer 58 of the associated threaded fastener assembly 12 as detailed below. The integral receiving member 68 can include a pair of hoops 68a, 68a. The hoops 68a, 68a may be at least partially spaced from one another so as to receive the rachet wheel 18. Further, each of the hoops 68a, 68a can define a hoop inner diameter 68b, 68b. As illustrated, the hoop inner diameters 68b, 68b are splined for engagement with the castle spline hubs 30 as will be described in more detail hereinafter. As will be appreciated, due to the symmetric layout of limited clearance hydraulic tool 10 (i.e., with regard to a plane created by the pivot head axis 52 and the pivot body axis 54), the limited clearance hydraulic tool 10 can engage the reaction washer 58 and nut 62 from either side of the plane created by the pivot head axis 52 and the pivot body axis 54 to change the rotational direction of the rachet 18 (i.e., to tighten or loosen the nut 62).
These improvements result in the limited clearance hydraulic tool 10 being of reduced weight as compared to conventional tools and also an improved profile that can be utilized in tight spaces. Further, as shown in the figures, the limited clearance hydraulic tool 10 can also include an endcap assembly 20 attached to the housing 14. The endcap assembly 20 can include a variety of elements that are either separate or integral that cooperate to seal the housing 14. For example, the endcap assembly 20 can include an endcap 20a. The endcap 20a can be removably attached to the housing 14 and provide a smooth design surface for the limited clearance hydraulic tool 10. Further, the endcap 20a can help to prevent unintentional access into the limited clearance hydraulic tool 10. Further still, the endcap assembly 20 can be detachable from the housing 14.
As mentioned hereinbefore, the limited clearance hydraulic tool 10 can include the first overlay 40a and the second overlay 40b. As shown in
This rotation of the rachet wheel 18 then causes rotation of the nut 62. However, because the integral receiving member 68 engages the reaction washer 58, which is stationary, the limited clearance hydraulic tool 10 is prevented from rotating about the nut 62. Instead, the nut 62 rotates about the rachet axis 22 of the limited clearance hydraulic tool 10. Thus, the housing 14 of the limited clearance hydraulic tool 10 remains stationary when the nut 62 is being rotated. As shown in
Each of the castle spline hubs 30 can define an inner diameter 30a for engagement with the outer diameter 58b of the reaction washer 58 and an outer diameter 30b for engagement with the respective inner diameter 68b of the hoop 68a of the integral receiving member 68. Notably, each of the inner diameters 30a of the spline hubs 30 can be castellated for selective engagement with outer diameter 58b of the reaction washer 58 and each of the outer diameters 30b of the spline hubs 30 can be splined for engagement with the inner diameter 68b of the respective hoop 68a. As will be appreciated, when the integral receiving member 68 engages the reaction washer 58, by way of one of the spline hubs 30, rotation between the reaction washer 58 and the limited clearance hydraulic tool 10 is prevented.
The rachet wheel 18 of the limited clearance hydraulic tool 10 is configured to receive the nut 62 of the threaded fastener assembly 12 so as to at least partially radially surround the nut 62. Further, the integral receiving member 68 engages the outer diameter 58b of the reaction washer 58 by way of one of the inner diameters 30a of the castle spline hubs 30. Then, as will be described in more detail hereinafter, when hydraulic fluid is supplied to the limited clearance hydraulic tool 10, the rachet wheel 18 will rotate.
With attention to
As noted hereinbefore, the limited clearance hydraulic tool 10 can include the piston 16. The piston 16 can be cylindrical in shape and be made of any number of materials that provide sufficient strength and rigidity for proper operation of the piston 16. The piston 16 is slidingly disposed within the piston cylinder 64 of the housing 14 and outputs force to cause subsequent movement of the rachet wheel 18. The piston 16 can travel between an extended position (
As is shown in the figures, the connection pin 34 can have a circular cross-section. Further, as illustrated in
With reference to
Further, the drive plate 26 can define a pin bore 96 that receives the connection pin 34 and includes a contact surface 94 that is spaced from the pin bore 96. Additionally, the drive plate 26 defines a wheel cavity 102 that receives the rachet wheel 18 and a pawl cavity 104 that receives the pawl 28. The pawl cavity 104 and the wheel cavity 102 are in fluid communication with one another.
The drive plate 26 can also include a first ear 106 and a second ear 112 that are spaced from one another. The first ear 106 and the second ear 112 can be of the same size and shape as one another. The first ear 106 can define a first ear bore 108 and the second ear 112 can define a second ear bore 114. The second ear bore 114 and the first ear bore 108 can be in registry with one another and cooperate with one another to define the pin bore 96 that receives the connection pin 34 to link the piston rod 32 and the drive plate 26 together to define the first point of contact.
With continued reference to the figures, the limited clearance hydraulic tool 10 also includes the push plate 38. The push plate 38 can include a contact face 122 that defines a concave shape in a cross-sectional plane that is orthogonal to the rachet axis 22. Further, the contact face 122 of the push plate 38 can be complementary to the contact surface 94 of the drive plate 26 so that the contact face 122 of the push plate 38 can at least partially cup the contact surface 94 of the drive plate 26. The push plate 38 can be separate from or integral with the piston rod 32 without departing from the scope of this disclosure.
As shown in
It is noted that the piston rod 32 can selectively deviate from the cylinder axis 66 when the piston 16 travels between the extended position (
With reference to
The internal radial surface 84 can define a hexagonal shape for complete engagement with the nut 62. However, it will be understood that the internal radial surface 84 could have a different shape to engage other shapes of nuts or fasteners without departing from the scope of this disclosure. The external radial surface 86 can define a grooved or tooth-like shape for engagement with the pawl 28. The rachet wheel 18 can be configured to only rotate in a single rotational direction.
As shown in
The stop surface 92 can be sized so as to contact the associated reaction washer 58 of the associated threaded fastener assembly 12 and prevent over-insertion of the associated threaded fastener assembly 12 into the limited clearance hydraulic tool 10 along the rachet axis 22. As will be appreciated, the magnetic properties of the magnetic ring 24 aid in operation of the limited clearance hydraulic tool 10 for improved engagement with the nut 62 of the associated threaded fastener assembly 12. Further, the stop surface 92 can improve operation of the limited clearance hydraulic tool 10 by providing a uniform surface for proper engagement with the associated threaded fastener assembly 12.
The limited clearance hydraulic tool 10 also includes the pawl 28. The pawl 28 simultaneously contacts the drive plate 26 and the rachet wheel 18. The pawl 28 is slidingly received in the pawl cavity 104 of the drive plate 26 to selectively engage the rachet wheel 18 and limit rotation of the rachet wheel 18 about the rachet axis 22 to a single rotational direction. As shown in
The limited clearance hydraulic tool 10 is configured to provide a first torque output for rotation of the associated threaded fastener assembly 12 in a first mode and a second torque output for rotation of the associated threaded fastener assembly 12 in a second mode. The second torque output is greater than the first torque output. As noted hereinbefore, the connection pin 34 can define a first point of contact between the piston rod 32 and the drive plate 26.
As shown in
With continued reference to
As will be appreciated, the ability of the limited clearance hydraulic tool 10 to operate in the first mode and the second mode without the installation/removal of components provides numerous advantages. For example, when the limited clearance hydraulic tool 10 is operated in the first mode, less wear and tear occurs to the components of the limited clearance hydraulic tool 10. Further, when the limited clearance hydraulic tool 10 is operated in the second mode, more torque is output to the nut 62 and operational efficiency of the limited clearance hydraulic tool 10 is improved. Additionally, since the force is transmitted through the first point of contact and the second point of contact in the second mode, the components are exposed to less force, thereby decreasing the need for maintenance of the limited clearance hydraulic tool 10.
Notably, the push plate 38 is continuously spaced from the drive plate 26 during the first mode. However, the push plate 38 contacts the drive plate 26 during the second mode. Furthermore, the contact face 122 is spaced from the connection pin 34 at all times. When the push plate 38 contacts and drives the drive plate 26, the connection pin 34 transfers a majority of the force output from the piston 16 to the drive plate 26 and the push plate 38 transfers a minority of the force output from the piston 16 to the drive plate 26. However, when the push plate 38 does not drive the drive plate 26, the connection pin 34 transfers all of the force output from the piston 16 to the drive plate 26 and the push plate 38 transfers none of the force output from the piston 16 to the drive plate 26. Further still, the push plate 38 is separate and unique from the first point of contact mentioned hereinbefore.
As such, the push plate 38 selectively connects the piston rod 32 and the drive plate 26 together for driving the drive plate 26, depending on the deflection of the connection pin 34. In particular, when a lower torque is being applied to the rachet wheel 18, the connection pin 34 does not deflect (i.e., remains completely straight and parallel to the rachet axis 22 inn all planes) and the push plate 38 is spaced from the drive plate 26 (
In contrast, when a higher torque is being applied to the rachet wheel 18, the connection pin 34 deflects (i.e., all points of the connection pin 34 are not uniformly spaced from the piston 16) so that the push plate 38 directly contacts the drive plate 26 (
It is also noted that the first point of contact and the second point of contact share a common concentric center so as to hold the piston rod 32 in position as the drive plate 26 moves. As illustrated, at least a portion of the pawl 28 shares a vertical axis with the second point of contact. Furthermore, the push plate 38 can be made of a first material that defines a first level of hardness and the connection pin 34 can be made of a second material that defines a second level of hardness. The first material and the second material are different from one another and the first level of hardness is greater than the second level of hardness. It will be appreciated that the level of hardness can be adjusted by a variety of methods, such as, for example heat treatment.
With reference back to
As is shown in
As mentioned hereinbefore, the housing 14 can define the channel 14a. In particular, as shown in
As shown in
As illustrated, the reaction pad 60 defines a length (i.e., in a direction parallel to the cylinder axis 66) that is greater than a length (i.e., in a direction parallel to the cylinder axis 66) of the channel 14a of the housing 14. This difference in length between the reaction pad 60 and the channel 14a results in the first end 60a of the reaction pad 60 being a distance from the pivot head axis 52 that is greater than a distance that the endcap 14a is from the pivot head axis 52. This length of the reaction pad 60 allows for improved engagement with the surrounding structure.
As will be appreciated, the reaction pad 60 could be of different lengths without departing from the scope of this disclosure. For example, the reaction pad 60 could define a length that was equal to the of the channel 14a of the housing 14. Such an arrangement would result in the first end 60a, and hence the reaction pad 60 protruding from the channel 14a, and hence the housing 14. Alternatively, the reaction pad 60 could define a length that is greater than what is illustrated, thereby resulting in a protrusion of the first end 60a of the reaction pad 60 to a greater extent than is illustrated. Finally, the reaction pad 60 could be made of a variety of materials without departing from the scope of this disclosure.
A limited clearance hydraulic tool has been described above in particularity. Modifications and alterations will occur to those upon reading and understanding the preceding detail description. The invention, however, is not limited to only the embodiment described above. Instead, the invention is broadly defined by the appended claims and the equivalents thereof.
