Patent Grant
7210720
1. Field of the Invention
The present invention relates generally to fluid-powered actuators and tool assemblies using such actuators, for timed rotational movement of two tool members positioned to cooperate with each other, typically mounted on a boom or arm of a vehicle or stationary platform.
2. Description of the Related Art
Assemblies such as large grapples, brush rakes, refuse collection tines or fingers, clamshell buckets, and buckets with bucket extensions or lids have been employed in the past for collection and sorting of large and small objects or quantities of material, excavation and picking up refuse containers. Many of these assemblies have two tools or members, which are selectively operable to work together. The assembly is generally attached to a boom or other arm of a platform such as a vehicle. The two tool members of the assembly are positioned to selectively move one toward and away from the other to cooperatively engage, pick up or grasp an object or material.
Generally, means are provided to separately supply rotational torque to the tool members in order to rotatable move one tool member relative to the other. The operational limitation of a particular assembly is directly dependent upon the maximum amount of torque that can be supplied to the tool members. If the torque is not sufficient, the object size or the quantity of the object or material to be engaged, picked up or grasped is limited.
It will therefore be appreciated that there has long been a significant need for an improved tool assembly and actuator used therewith. The present invention fulfills these needs and further provides other related advantages.
The present invention resides in a fluid-powered rotary actuator for providing timed rotational movement of first and second external members, typically tool members. The actuator includes a body having a longitudinal axis, a first rotatable member, second rotatable member, and a linear-to-rotary force transmitting member. The first rotatable member is rotatably disposed with respect to the body for rotation about a first rotation axis with a portion adapted for coupling to the first external member for rotational movement of the first external member with the first rotatable member as a unit. The second rotatable member rotatably is disposed with respect to the body for rotation about a second axis with a portion adapted for coupling to the second external member for rotational movement of the second external member with the second rotatable member as a unit.
The linear-to-rotary force transmitting member is mounted for reciprocal longitudinal movement in response to selective application of pressurized fluid thereto. The force transmitting member engages the first and second rotatable members to translate longitudinal movement of the force transmitting member in a first longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in a first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in a second rotational direction, and to translate longitudinal movement of the force transmitting member in a second longitudinal direction opposite the first longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in a rotational direction opposite the first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in a rotational direction opposite the second rotational direction.
In one embodiment of the actuator, the force transmitting member engages the body to translate longitudinal movement of the force transmitting member in the first and second longitudinal directions into rotational movement of the first and second rotatable members about the first and second axes, respectively, relative to the body.
The first and second rotational directions may be opposite rotational directions, with rotational movement of the first and second rotatable members in the first and second rotational directions, respectively, in response to longitudinal movement of the force transmitting member in the first longitudinal direction, producing movement of the first and second external members toward each other, and rotational movement of the first and second rotatable members in the rotational directions opposite the first and second rotational directions, respectively, in response to longitudinal movement of the force transmitting member in the second longitudinal direction, producing movement of the first and second external members away from each other.
An embodiment of the actuator using third and fourth rotatable members may also be constructed with the third rotatable member rotatably disposed with respect to the body for rotation about a third rotation axis, with the third rotatable member having a portion adapted for coupling to the second external member for rotational movement of the second external member with the third rotatable member as a unit. The fourth rotatable member rotatably may be disposed with respect to the body for rotation about a fourth rotation axis, with the fourth rotatable member having a portion adapted for coupling to the first external member for rotational movement of the first external member with the fourth rotatable member as a unit. The linear-to-rotary force transmitting member may engage the third and fourth rotatable members to translate longitudinal movement of the force transmitting member in the first longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in a third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in a fourth rotational direction, and to translate longitudinal movement of the force transmitting member in the second longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in the rotational direction opposite the third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in the rotational direction opposite the fourth rotational direction.
The actuator may be constructed with the first and second rotatable members each having a grooved portion, and with the force transmitting member having a grooved first portion engaging the first rotatable member grooved portion and a grooved second portion engaging the second rotatable member grooved portion to translate longitudinal movement of the force transmitting member in the first longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in the first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in the second rotational direction, and to translate longitudinal movement of the force transmitting member in the second longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in the rotational direction opposite the first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in the rotational direction opposite the second rotational direction.
In this embodiment, the actuator includes a third rotatable member rotatably disposed with respect to the body for rotation about a third rotation axis, the third rotatable member having a portion adapted for coupling to the second external member for rotational movement of the second external member with the third rotatable member as a unit, with the third rotatable member having a grooved portion. The actuator of this embodiment further includes a fourth rotatable member rotatably disposed with respect to the body for rotation about a fourth rotation axis, the fourth rotatable member having a portion adapted for coupling to the first external member for rotational movement of the first external member with the fourth rotatable member as a unit, with the fourth rotatable member having a grooved portion. The linear-to-rotary force transmitting member has a grooved third portion engaging the third rotatable member grooved portion and a grooved fourth portion engaging the fourth rotatable member grooved portion to translate longitudinal movement of the force transmitting member in the first longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in a third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in a fourth rotational direction, and to translate longitudinal movement of the force transmitting member in the second longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in the rotational direction opposite the third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in the rotational direction opposite the fourth rotational direction.
The actuator may be constructed with the body also having a grooved portion. In this embodiment, the first rotatable member has a grooved portion, and the second rotatable member has a grooved portion. The force transmitting member has a grooved first portion engaging the first rotatable member grooved portion, a grooved second portion engaging the second rotatable member grooved portion and a grooved third portion engaging the body grooved portion to translate longitudinal movement of the force transmitting member in the first longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in the first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in the second rotational direction, and to translate longitudinal movement of the force transmitting member in the second longitudinal direction into rotational movement of the first rotatable member about the first axis relative to the body in the rotational direction opposite the first rotational direction and into rotational movement of the second rotatable member about the second axis relative to the body in the rotational direction opposite the second rotational direction.
This embodiment may also include a third rotatable member and a fourth rotatable member, much as described above. The linear-to-rotary force transmitting member has a grooved fourth portion engaging the third rotatable member grooved portion and a grooved fifth portion engaging the fourth rotatable member grooved portion to translate longitudinal movement of the force transmitting member in the first longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in a third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in a fourth rotational direction, and to translate longitudinal movement of the force transmitting member in the second longitudinal direction into rotational movement of the third rotatable member about the third axis relative to the body in the rotational direction opposite the third rotational direction and into rotational movement of the fourth rotatable member about the fourth axis relative to the body in the rotational direction opposite the fourth rotational direction.
In at least one embodiment of the actuator, the first rotatable member includes an idler mount portion adapted to rotatably mount a portion of the second external member thereto to allow independent rotation of the second external member relative to the first shaft idler mount portion, and the second rotatable member includes an idler mount portion adapted to rotatably mount a portion of the first external member thereto to allow independent rotation of the first external member relative to the second shaft idler mount portion.
In one embodiment of the actuator designed for use with a third external member, the body is adapted for coupling to the third external member for movement of the body with the third external member as a unit. The body includes a central tie rod positioned along the body axis and retaining the first and second rotatable members against longitudinally outward movement relative to each other. The tie rod comprises at least a portion of the body adapted for coupling to the third external member.
In one embodiment, the body of the actuator has spaced apart first and second longitudinal end portions, with the portions of the first and second rotatable members adapted for coupling to the first and second external members are both located at the body first end portion.
The invention may also be embodied with the actuator having a body with spaced apart first and second longitudinal end portions, with the first and second rotatable members each extending between the body first and second end portions and with the first and second rotation axes thereof in spaced apart arrangement. In this embodiment, the first rotatable member may have first and second end portions, each adapted for coupling to the first external member, and the second rotatable member may have first and second end portions, each adapted for coupling to the second external member. The first end portions of the first and second rotatable members is located at the body first end portion and the second end portions of the first and second rotatable members are located at the body second end portion. The force transmitting member may be a piston sleeve with first and second spaced apart apertures therein and having the first rotatable member extending through the first aperture and the second rotatable member extending through the second aperture.
In yet another embodiment of the actuator, the body is a first body and the actuator includes a second body, with the first body being rotatable relative to the second body. Further, the actuator may have another linear-to-rotary force transmitting member mounted for reciprocal longitudinal movement in the first and second longitudinal directions in response to selective application of pressurized fluid thereto. The another force transmitting member engages the first and second bodies to translate longitudinal movement of the another force transmitting member in a third longitudinal direction into one of clockwise or counterclockwise relative rotational movement of the first body relative to the second body and to translate longitudinal movement of the another force transmitting member in a fourth longitudinal direction into the other of clockwise or counterclockwise relative rotational movement of the first body relative to the second body.
Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.
As shown in the drawings for purposes of illustration, the present invention is embodied in a fluid-powered tool assembly 10 and a fluid-powered rotary actuator 12 used therewith for timed rotation of first and second tool members 14 and 16. As shown in
A boom mounting member 20 is pivotally connected to the upper end of the boom arm 18, and if desired, can be rotated relative to the boom arm using conventional hydraulic cylinders, rotary actuators or other actuation means (not shown). The tool assembly 10 is rigidly attached to the boom mounting member 20 for movement therewith. In other applications, the tool assembly 10 may be mounted to other mounting surfaces, platforms or frames, as appropriate to perform the work desired using the tool assembly.
A first embodiment of the tool assembly 10 is illustrated in
The first and second tool members 14 and 16 are connected to the actuator 12 for timed rotational movement of the first and second tool members, often toward and away from each other. Other tools may have different timed rotational movement. The actuator provides rotational torque to the first and second tool members.
Referring to the tool assembly 10 of
While the tool assembly 10 of
The construction of the actuator 12 and the attachment of the first and second tool members 14 and 16 thereto are shown in
Exteriorly threaded first and second annular retainer nuts 58 and 60 are positioned within the body 42. The first retainer nut 58 is threadably attached to an interiorly threaded portion of the body sidewall 44 toward the first body end 46 and the second retainer nut 60 is threadably attached to an interiorly threaded portion of the body sidewall 44 toward the second body end 48. The first and second retainer nuts 58 and 60 are located axially outward of the corresponding first and second shoulders 54 and 56 of the body sidewall 44, with the flange portion 50B of the first shaft 50 positioned between the first shoulder 54 and the first retainer nut 58 to prevent axial movement of the first shaft within the body 42, and the flange portion 52B of the second shaft 52 positioned between the second shoulder 56 and the second retainer nut 60 to prevent axial movement of the second shaft within the body. The first and second shaft nuts 58 and 60 are locked in place against rotation with the first and second shafts 50 and 52.
Thrust bearings 62 are disposed between the first and second shaft flange portions 50B and 52B, and both of the corresponding first and second shoulders 54 and 56, and the first and second retainer nuts 58 and 60 to support the first and second shafts against longitudinal thrust loads. A radial bearing 64 is positioned between each of the first and second shafts 50 and 52 and the corresponding first and second retainer nuts 58 and 60 to support the shafts against radial loads. Seals 66 are disposed between the first and second shaft nuts 58 and 60, and both of the corresponding first and second shafts 50 and 52, and the body sidewall 44 to provide a fluid-tight seals therebetween.
The exterior end surfaces of the attachment portions 50A and 52A of the first and second shafts 50 and 52 are flat and each have a plurality of threaded apertures 70 and 72, respectively, which threadably receive attachment bolts 74. The first tool member 14 has a first side projecting attachment portion 14A and a second side projecting attachment portion 14B, and the second tool member 16 has a first side projecting attachment portion 16A, and a second side projecting attachment portion 16B for attachment of the first and second tool members to the actuator 12. In the case of the illustrated clamshell buckets, these comprise portions of the right and left sidewalls of each bucket.
As can best be seen in
Similarly, the second attachment portion 16B of the second tool member 16 is positioned in contact with the end surface of the attachment portion 52A of the second shaft 52 and rigidly attached thereto by the attachment bolts 74 for rotational movement with the second shaft. The second attachment portion 16B of the second tool member 16 is clamped between a second end support member 78 and the second shaft attachment portion 52A by the attachment bolts 74 which extend through apertures in the second end support member 78 and the second attachment portion 16B of the second tool member 16 and are threadably received in the threaded apertures 72. The second attachment portion 14B of the first tool member 14 is rotatably mounted (idle mounted) on the second end support member 78 so that it can rotate freely, independent of the second shaft 52 to which the second end support member is rigidly attached, but yet be supported by the second end support member against loads encountered during use by the first tool member. This is accomplished by providing the second attachment portion 14B of the first tool member 14 with an aperture 14C through which the second end support member 78 projects. An axially outward retainer flange 78A which allows independent rotation of the first tool member 14 but retains it in place on the second end support member 78. Bearings may be used to facilitate the rotation. This construction provides a straddle mounting of the first and second tool members 14 and 16 to the actuator 12 which for a wide tool like the clamshell buckets illustrated in
As shown in
The meshing splines can be threaded in the direction (e.g., left-handed or right-handed) and with the lead desired to produce simultaneous counter-rotation of the first and second tool members 14 and 16 in a desired amount per unit of axial motion of the piston 82, as would typically be the case for the clamshell buckets illustrated in
In the actuator 12 of
As will be readily understood, reciprocation of the piston 82 within the body 42 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of a first port P1 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head portion 104 toward the first body end 46 or through a second port P2 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head portion toward the second body end 48. As the piston head portion 104 and the piston 82, of which the piston head portion is a part, linearly reciprocates in an axial direction within the body 42, the outer splines 98 of the piston mid-portion 96 engage or mesh with the inner splines 102 of the body sidewall 44 to prevent rotation of the piston, where both the outer splines 98 and the inner splines 102 are straight. If desired, the splines 98 and 102 may be helical to also cause rotation of the piston 82 as it linearly reciprocates within the body 42. The linear and rotational movement of the piston 82 is simultaneously transmitted through the outer splines 88 and 92 of the piston to the inner splines 90 and 94, respectively, of the first and second shafts 50 and 52 to cause the shafts to simultaneously rotate. The smooth interior wall portion 110 of the body sidewall 44 has sufficient axial length to accommodate the full end-to-end reciprocating stroke travel of the piston 82 within the body 42. As noted above, longitudinal movement of the first and second shafts 50 and 52 is restricted, thus linear movement of the piston 82 is converted into rotational movement of the first and second shafts. The amount of rotation and the output torque produced depends on the slope and direction of turn of the various splines, and the fluid pressure used.
In more detail, the application of fluid pressure to the first port P1 produces axial movement of the piston 82 toward the second body end 48. The application of fluid pressure to the second body port P2 produces axial movement of the piston 82 toward the body first end 46. The actuator 12 provides simultaneous rotational movement of the first and second shafts 50 and 52, relative to the body 42 (and hence relative to the boom mounting member 20 to which attached) through the conversion of linear movement of the piston 82 into rotational movement of the shafts. The first and second shafts 50 and 52 are selectively rotated by the application of fluid pressure, and the rotation is transmitted to the first and second tool members 14 and 16 to selectively rotate the first and second tool members about the axis 22 of the actuator 12 relative to the body 42. The rotary drive to the first tool member 14 is transmitted by the first shaft 50 by its rigid attachment thereto at the first body end 46, and the rotary drive to the second tool member 16 is transmitted by the second shaft 52 by its rigid attachment thereto at the second body end 48.
The body 42 of the actuator 12 has mounting flanges 112 by which the body is attached to a mounting face 114 of the boom mounting member 20 using attachment bolts 116, as best seen in
An alternative actuator 12 is shown in
An alternative embodiment of the fluid-powered tool assembly 10 is shown in
If appropriate for the work to be performed, especially if each of the first and second tool members has multiple tines (such as 2, 3 or 4 spaced apart along the length of the actuator) and the loads on the actuator 12 would be too great, the first and second tool members may be straddle mounted on the actuator much as described above for the clamshell buckets of
Another alternative embodiment of the fluid-powered tool assembly 10 is shown in
In this embodiment, the first and second tool members 14 and 16 are a pair of opposing curved fingers or tines sized to grasp and pickup a refuse container 128. As described above, the first and second tool members 14 and 16 are connected to the actuator 12 for simultaneous timed rotational movement toward and away from each other, for grasping and releasing the refuse container 128 therebetween. The lower end of the boom 126 is pivotable by an operator 130 that can pivot the boom to a position to operate the tool members 14 and 16 to grasp the refuse container 128 when containing refuse, then pivot the boom to the position illustrated in
In the refuse collection embodiment illustrated, the first and second tool members 14 and 16 are each a single tine having an axially inward bend 132 so that the tines of the first and second tool members are each offset axially inward to rotate through adjacent transverse parallel planes approximately midway between the first and second body ends 46 and 48 of the actuator 12.
An alternative embodiment of the first and second tool members 14 and 16 usable with the tool assembly 10 for refuse collection is shown in
Another embodiment of the actuator 12, in many ways similar to the embodiment of
The attachment portions 50A and 52A each have splines 118 by which they transmit rotary drive to the attachment portion 14A of the first tool member 14 and to the first attachment portion 16A of the second tool member 16, respectively, rather than using the attachment bolts 74 shown in
In the embodiment of the actuator 12 shown in
The second shaft 52 has an axially inward facing shoulder 142 positioned axially outward of the radially inward flange portion 50E of the first shaft 50. An interiorly threaded annular retainer nut 144 is positioned within the body 42, and is threadably attached to an exteriorly threaded portion of the second shaft 52 toward the first body end 46 to position the retainer nut 144 axially inward of the second shaft shoulder 142. The radially inward flange portion 50E of the first shaft 50 is positioned between the second shaft shoulder 142 and the retainer nut 144 to prevent axial movement of the second shaft 52 within the central opening 50D of the first shaft 50, and hence prevent axial movement of the second shaft relative to the body 42. The retainer nut 144 is locked in place for rotation with the second shaft 52.
Much as with the first discussed embodiment, thrust bearings 62 are disposed between the first shaft flange portion 50B of the first shaft 50, and both of the first shoulder 54 of the body sidewall 44 and the end cap 134 to support the first shaft against longitudinal thrust loads. Additionally, thrust bearings 62 are disposed between the radially inward flange portion 50E of the first shaft 50, and both of the second shaft shoulder 142 and the retainer nut 144 to support the second shaft 52 against longitudinal thrust loads. Radial bearing 64 are positioned in this embodiment between the first shaft 50 and the body sidewall 44 and between the radially outward face of the first shaft flange portion 50B and the body sidewall axially outward of the first shoulder 54 to support the first shaft against radial loads. Additionally, radial bearing 64 are positioned between the first and second shafts 50 and 52 and between the retainer nut 144 and the first shaft to support the second shaft against radial loads. Seals 66 are disposed between the first shaft 50 and both the end cap 134 and the body sidewall 44, and between the first and second shafts 50 and 52 to provide a fluid-tight seals therebetween.
The piston 82 used in the actuator 12 of the embodiment of
The meshing splines can be threaded in the direction (e.g., left-handed or right-handed, or straight, as appropriate) and with the lead desired to produce simultaneous counter-rotation of the first and second shafts 50 and 52, and hence the first and second tool members 14 and 16 attached thereto, in a desired amount per unit of axial motion of the piston 82, but also may be splined to produce simultaneous rotation of the first and second tool members in the same rotational direction.
As described above for the embodiment of the actuator 12 shown in
As noted above, longitudinal movement of the first and second shafts 50 and 52 is restricted, thus linear movement of the piston 82 is converted into rotational movement of the first and second shafts. The amount of rotation depends on the lead of the various splines and the stroke of the piston, and the output torque produced depends on the slope and direction of turn of the various splines, and the piston force generated by the fluid pressure.
The mounting flanges 112 of the actuator 12 of
Another embodiment of the actuator 12 is shown in
Much as described above for the embodiment of
The separate first and second shafts 50′ and 52′ are coaxially positioned within the body 42 and supported for rotation relative to the body 42, with the first shaft 50′ being in the form of a sleeve having a central opening 50D extending axially fully therethrough. The second shaft 52′ is concentrically, rotatably mounted within the central opening 50D of the first shaft 50′. The first shaft 50′ extends axially out of the body 42 at the second body end 48, and has an attachment portion 50A at the second body end. The second shaft 52′ also extends axially out of the body 42 at the second body end 46, extending outward beyond the end of the first shaft 50′, and has an attachment portion 52A at the second body end. The attachment portions 50A and 52A each have splines 118 by which they transmit rotary drive to the second attachment portion 14B of the first tool member 14 and to the second attachment portion 16B of the second tool member 16, respectively. Of course, the second attachment portion 14B and the second attachment portion 16B of the first and second tool members 14 and 16 to be used with the actuator 12 will have corresponding mating splines. As noted above, the tool members may comprise various type work tools, including clamshell buckets, brush rakes, grapples or refuse can collection fingers or tines, to name a few.
In the embodiment of the actuator 12 shown in
The second shaft 52′ has an axially inward facing shoulder 142 positioned axially outward of the radially inward flange portion 50E of the first shaft 50′. An interiorly threaded annular retainer nut 144 is positioned within the body 42, and is threadably attached to an exteriorly threaded portion of the second shaft 52′ toward the second body end 48 to position the retainer nut 144 axially inward of the second shaft shoulder 142 of the second shaft 52′. The radially inward flange portion 50E of the first shaft 50′ is positioned between the second shaft shoulder 142 of the second shaft 52′ and the retainer nut 144 to prevent axial movement of the second shaft 52′ within the central opening 50D of the first shaft 50′, and hence prevent axial movement of the second shaft 52′ relative to the body 42. The retainer nut 144 is locked in place for rotation with the second shaft 52′. As with the first and second shafts 50 and 52 described with respect to
The piston 82 used in the actuator 12 of the embodiment of
Reciprocation of the piston 82 within the body 42 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of the first port P1 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head portion 104 toward the first body end 46 or through the second port P2 which is in fluid communication with a fluid-tight compartment within the body to a side of the piston head portion toward the second body end 48. As the piston head portion 104 and the piston 82 linearly reciprocates in an axial direction within the body 42, the outer splines 98 of the piston mid-portion 96 engage or mesh with the inner splines 102 of the body sidewall 44 to prevent rotation of the piston, where both the outer splines 98 and the inner splines 102 are straight. The linear and rotational movement of the piston 82 is simultaneously transmitted through the outer splines 88 and the inner splines 92 of the piston first end sleeve portion 146 to the inner splines 90 of the first shaft 50 and the outer splines 94 of the second shaft 52, respectively, and simultaneously transmitted through the outer splines 88 and the inner splines 92 of the piston second end sleeve portion 148 to the inner splines 90 of the first shaft 50′ and the outer splines 94 of the second shaft 52′, respectively, to cause the first and second shafts 50 and 52 and the first and second shafts 50′ and 52′ to all simultaneously rotate. The splines are selected to cause the first shafts 50 and 50′ to rotate in the same direction, and the second shafts 52 and 52′ to rotate in the same direction, but typical opposite or counter to the direction of rotation of the first shafts so that the first and second tool members 14 and 16 attached to the shafts selectively rotate toward and away from each other. The shafts rotate relative to each other and each rotates relative to the body 42 and the boom mounting member 20 or other mounting surface, platform or frame to which the body is mounted when the piston 82 is moved linearly by the application of fluid pressure to one of the first and second body ports P1 and P2.
The longitudinal movement of the first and second shafts 50 and 52 and the first and second shafts 50′ and 52′ is restricted, thus linear movement of the piston 82 is converted into rotational movement of the shafts.
As with the embodiment of
Yet another embodiment of the actuator 12 is shown in
As with other embodiments, the first and second shafts 50 and 52 are coaxially positioned within the body 42 and supported for rotation relative to the body. The first shaft 50 extends axially out of the body 42 at the first body end 46, and has an attachment portion 50A in the form of a flange located axially outward of the first body end 46 to which the first tool member 14 may be connected. The second shaft 52 extends axially out of the body 42 at the second body end 48, and has an attachment portion 52A in the form of a flange located axially outward of the second body end 48 to which the second tool member 16 may be connected. The first shaft 50 further includes an axially inward facing end wall portion 50F positioned within the body 42 inward of the first body end 46 adjacent to the axially outward facing first shoulder 54 of the body sidewall 44 to prevent axial inward movement of the first shaft 50. Similarly, the second shaft 52 further includes an axially inward facing end wall portion 52F positioned within the body 42 inward of the second body end 48 adjacent to the axially outward facing second shoulder 56 of the body sidewall 44 to prevent axial inward movement of the second shaft 52.
The first and second shafts 50 and 52 each further include a radially inward flange portion 50E and 52E, respectively. The radially inward flange portion 50E is positioned axially outward of the first body end 46, and the radially inward flange portion 52E is positioned axially outward of the second body end 48. The tie rod 150 includes a head portion 152 positioned axially outward of the radially inward flange portion 52E of the second shaft 52 and adjacent thereto to prevent axial outward movement of the second shaft 52. The tie rod 150 further includes an elongated shaft portion 154 extending along the longitudinal axis 22 of the actuator 12 and having an exteriorly threaded end portion 156 positioned axially outward of the radially inward flange portion 50E of the first shaft 50. A tie rod retainer nut 158 is threadably attached to the tie rod threaded end portion 156. An annular end cap 160 is positioned axially outward of the radially inward flange portion 50E of the first shaft 50 and adjacent thereto to prevent axial outward movement of the first shaft 50. The end cap 160 has a central aperture through which the tie rod shaft portion 154 extends axially outward beyond the end cap. The tie rod retainer nut 158 prevents axial outward movement of the end cap 160. The tie rod retainer nut 158 is locked in place against rotation on the tie rod threaded end portion. As with the embodiments described above, thrust bearings 62, radial bearing 64 and seals 66 are provided.
The actuator 12 of
The piston 82 used in the actuator 12 of the embodiment of
In the embodiment of
As before, the meshing splines can be threaded in the direction (e.g., left-handed or right-handed) and with the lead desired to produce simultaneous counter-rotation of the first and second shafts 50 and 52, and hence the first and second tool members 14 and 16 attached thereto, in a desired amount per unit of axial motion the piston 82, but also may be splined to produce simultaneous rotation of the first and second tool members in the same rotational direction.
As described above for other embodiments of the actuator 12, reciprocation of the piston 82 within the body 42 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of the first port P1 which is in fluid communication with a fluid-tight compartment within the body toward the first body end 46 or through the second port P2 which is in fluid communication with a fluid-tight compartment within the body toward the second body end 48. In the embodiment of
Since longitudinal movement of the first and second shafts 50 and 52 is restricted, linear movement of the piston 82 is converted into rotational movement of the first and second shafts.
Another embodiment of the actuator 12 is shown in
The piston 82 of the embodiment of
Reciprocation of the piston 82 within the body 42 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of the first port P1 which is in fluid communication with a fluid-tight compartment within the body toward the first body end 46 or through the second port P2 which is in fluid communication with a fluid-tight compartment within the body toward the second body end 48. As the piston 82 linearly reciprocates in an axial direction within the body 42, the inner splines 182 of the piston 82 located within the piston apertures 82B engage or mesh with the outer splines 180 of the first and second shafts 50 and 52 to cause rotation of the first and second shafts. Since the first and second shafts 50 and 52 are laterally spaced apart, the piston 82 cannot rotate as it moves longitudinally within the body 42. As such, and since longitudinal movement of the first and second shafts 50 and 52 is restricted, the linear movement of the piston is simultaneously transmitted through the inner splines 182 of the piston to the outer splines 180 of the shafts to cause the shafts to simultaneously rotate. In such manner, the first and second tool members 14 and 16 (not shown in
Another embodiment of the actuator 12 is shown in
In particular, the actuator 12 has an elongated outer housing or body 186 with a cylindrical sidewall 188 and first and second longitudinal ends 190 and 192, respectively. The outer body 186 has the mounting flanges 112 for mounting of the body the mounting face 114 of the boom mounting member 20 or some other mounting surface, platform or frame. The body 42 of the inner actuator, described above for the actuator of
In the embodiment of the actuator 12 of
The exterior end surfaces of the attachment portions 50A and 52A of the first and second shafts 50 and 52 are flat and each have threaded apertures 70 and 72 to allow attachment of the first and second tool members 14 and 16 thereto. The first and second end support members 76 and 78 described above for the actuator of
The construction and operation of the inner actuator is generally as described above for the actuator of
The actuator 12 of
Reciprocation of the outer piston 194 within the outer body 186 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of a third port P3 which is in fluid communication with a fluid-tight compartment within the outer body 186 to a side of the piston head portion 195 toward the first body end 190 or through a fourth port P4 which is in fluid communication with a fluid-tight compartment within the outer body 186 to a side of the piston head portion 195 toward the second body end 192. As the piston head portion 195 and the outer piston 194 linearly reciprocates in an axial direction within the outer body 186, the outer splines 196 of the outer piston 194 engage or mesh with the inner splines 198 of the outer body sidewall 188 to cause rotation of the outer piston, where both the outer splines 196 and the inner splines 198 are helical. The rotational movement of the outer piston 194 is transmitted through the inner splines 200 of the outer piston to the outer splines 202 of the inner body sidewall 44 of the inner body 42 to cause the inner body, and the first and second shafts 50 and 52, to rotate as a unit relative to the outer body 186. In such manner, the first and second tool members 14 and 16 attached to the first and second shafts 50 and 52 rotate relative to the outer body 186 and to the boom mounting member 20 or other mounting surface, platform or frame to which the outer body is mounted when the outer piston 194 is moved linearly by the application of fluid pressure to one of the third and fourth ports P3 and P4. By way of example using grapples as the first and second tool members 14 and 16, the resulting movement by operation of the inner actuator is timed rotation of the grapple tines about the axis 22 serving much like grabbing with the fingers of a hand, and the resulting movement by operation of the outer actuator is rotation of the grapple tines as a unit about the axis 22 much like the rotation of a wrist to provide a high torque articulated tool.
Another embodiment of the actuator 12 is shown in
In particular, rather than using the central tie rod of the embodiment of
In the actuator 12 of
The radially inward flange portion 50E of the first shaft 50 is positioned axially outward of the first body end 46, and the radially inward flange portion 52E of the second shaft 52 is positioned axially outward of the second body end 48. The inner body 204 has first and second annular retainer nuts 212 and 214 threadably attached to outer threaded portions of the first and second body ends 208 and 210, respectively, of the inner body. The retainer nut 212 is positioned axially outward of the radially inward flange portion 50E of the first shaft 50 and adjacent thereto to prevent axial outward movement of the first shaft 50. The retainer nut 214 is positioned axially outward of the radially inward flange portion 52E of the second shaft 52 and adjacent thereto to prevent axial outward movement of the second shaft 52.
The attachment portion 50A of the first shaft 50 is in the form of a flange located axially outward of the first body end 46 to which the first tool member 14 may be connected. The attachment portion 52A of the second shaft 52 is in the form of a flange located axially outward of the second body end 46 to which the second tool member 16 may be connected.
The inner body 204 further has third and fourth annular retainer nuts 216 and 218 threadably attached to inner threaded portions of the first and second body ends 208 and 210, respectively, of the inner body. The third and fourth retainer nuts 216 and 218 each has a central aperture 220 through which a shaft 222 extends for positioning the shaft 222 along the longitudinal axis 22 of the inner actuator within the inner body 204. The shaft 222 has first and second end portions 224 and 226 that extend axially outward beyond the third and fourth retainer nuts 216 and 218, respectively. The first and second end portions 224 and 226 of the shaft 222 have splines 228 by which the shaft 222 may be attached to a mounting surface, platform or frame.
The construction and operation of the outer actuator is generally as described above for the actuator of
The actuator 12 of
Reciprocation of the inner piston 230 within the inner body 204 occurs when hydraulic oil, air or any other suitable fluid under pressure selectively enters through one or the other of a third port P3 which is in fluid communication with a fluid-tight compartment within the inner body 204 to a side of the piston head portion 232 toward the first body end 208 or through a fourth port P4 which is in fluid communication with a fluid-tight compartment within the inner body 204 to a side of the piston head portion 232 toward the second body end 210. As the piston head portion 232 and the inner piston 230 linearly reciprocates in an axial direction within the inner body 204, the inner splines 234 of the inner piston 230 engage or mesh with the outer splines 236 of the shaft 222 to cause rotation of the inner piston, where both the inner splines 234 and the outer splines 236 are helical. The linear and rotational movement of the inner piston 230 is transmitted through the outer splines 238 of the inner piston to the inner splines 240 of the inner body sidewall 206 of the inner body 204 to cause the inner body, which carries the outer body 42 and the first and second shafts 50 and 52 therewith, to rotate as a unit relative to the shaft 222. In such manner, the first and second tool members 14 and 16 attached to the first and second shafts 50 and 52 rotate relative to the shaft 222 and to the boom mounting member 20 or other mounting surface, platform or frame to which the shaft 222 is mounted when the inner piston 230 is moved linearly by the application of fluid pressure to one of the third and fourth ports P3 and P4. Again by way of example using grapples as the first and second tool members 14 and 16, the resulting movement by operation of the outer actuator is timed rotation of the grapple tines about the axis 22 serving much like grabbing with the fingers of a hand, and the resulting movement by operation of the inner actuator is rotation of the grapple tines as a unit about the axis 22 much like the rotation of a wrist to provide a high torque articulated tool. This is the reverse of the actuator of
It should be understood that while splines are shown in the drawings and described herein, the principle of the invention is equally applicable to any form of linear-to-rotary motion conversion arrangement, such as balls or rollers, and that the splines can include any type of groove, thread or channel suitable for such motion conversion.
It will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 2945387 | Geyer | Jul 1960 | A |
| 3343693 | Becker | Sep 1967 | A |
| 4590816 | Weyer | May 1986 | A |
| 4607873 | Nusbaumer et al. | Aug 1986 | A |
| 4667528 | Weyer | May 1987 | A |
| 4683767 | Weyer | Aug 1987 | A |
| 4691582 | Weyer | Sep 1987 | A |
| 4741250 | Weyer | May 1988 | A |
| 4745847 | Voss | May 1988 | A |
| 4773812 | Bayne et al. | Sep 1988 | A |
| 4858486 | Weyer | Aug 1989 | A |
| 4858701 | Weyer | Aug 1989 | A |
| 4881419 | Weyer | Nov 1989 | A |
| 4945778 | Weyer | Aug 1990 | A |
| 4960007 | Weyer | Oct 1990 | A |
| 5027667 | Weyer | Jul 1991 | A |
| 5487230 | Weyer | Jan 1996 | A |
| 5671652 | Weyer | Sep 1997 | A |
| 6370801 | Weyer et al. | Apr 2002 | B1 |
| 6896306 | Schierholz | May 2005 | B2 |
| Number | Date | Country |
|---|---|---|
| 20107206 | Apr 2001 | DE |
| 0218714 | Mar 2002 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20040000811 A1 | Jan 2004 | US |
