JPS6128488Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rotary actuator in which one member performs a controlled and limited rotational movement relative to another member, and particularly relates to a rotary actuator operated by fluid pressure. .

Controlled changes in the rotational position of one part of a machine relative to another are often accomplished by coupling a hydraulically actuated rotary actuator between the two parts. For example, a bucket hoe attachment mounted on a vehicle to excavate ground typically includes a hydraulic rotary actuator that allows the excavating member to pivot about an axis perpendicular to the vehicle. Similar rotary actuators are used in a variety of other types of devices.

This type of rotary actuator includes a housing and an actuator shaft that together define an annular interior chamber. A divider member affixed to the housing extends into the chamber to the actuator shaft, and a pivotable vane affixed to the actuator shaft extends to the housing. When pressurized fluid is introduced into the chamber on one side of the bulkhead member and fluid is simultaneously discharged from the chamber on the other side, the vane and actuator shaft are rotated by a desired amount relative to the housing. can be Seals are typically provided along the line of vane-to-diaphragm contact with the interior wall of the chamber and along the line of contact between the septum member and the actuator shaft to prevent fluid flow. Efficiency loss and loss of precision control resulting from leakage are prevented.

As a result of internal damage due to metal particulates due to wear accumulating in the chamber of the rotary actuator, durability is reduced and maintenance problems are complicated. As the harder and more abrasive contaminant particles are generated from the abrasive action of the metal parts of the device, they tend to be predominantly ferromagnetic. Particles that accumulate at the bottom of the chamber are repeatedly moved back and forth by the movement of the rotary actuator vanes and damage the seal and chamber walls. This ultimately necessitates replacement of parts of the rotary actuator, with expensive cleaning operations required in between.

Damage due to metal contaminants is relatively more likely to occur in rotary actuators than in other types of hydraulic motors. The cleaning effect of the fluid flow entering the rotary actuator is generally relatively small. When used in the above-mentioned vacuum hoe, most of the fluid volume is generally used in the piston and cylinder type actuators that operate the various devices. Additionally, it has become common practice to use a separate fluid source for rotary actuators. Because the flow requirements are small, filters may not be used in the fluid circuit.

To minimize damage from contaminant particles, it has heretofore been necessary to periodically disassemble and clean rotary actuators. This also includes draining and preferably replacing the fluid in the rotary actuator.
These maintenance operations are undesirable, cumbersome, expensive and time consuming, and at best do not prevent wear and tear as effectively as desired.

The present invention seeks to overcome one or more of the problems set forth above.

According to the present invention, the rotary actuator includes a housing device defining a vane chamber, an actuator shaft extending into the vane chamber and rotatable with respect to the housing device, and a housing device defining a vane chamber. a vane extending radially from the actuator shaft and discharging a liquid corresponding to the displacement amount of the vane chamber by pivoting between the opposite end positions of the vane; a port device for allowing pressurized fluid to enter and exit the vane chamber via a flow path opening into the vane chamber to pivot the vane and rotate the actuator shaft. a trapping device for retaining contaminant particles of the pressurized fluid within the vane chamber and in an area outside the range of pivoting movement of the vane;
The trapping device includes at least a pair of spaced apart contaminant particulate retaining recesses formed in the housing device and open to the vane chamber, a first of the recesses is adjacent one end of the vane travel path, and the other of the recesses is adjacent the other end of the vane travel path.

According to one aspect of the invention, the rotary actuator includes a magnetic device for retaining ferromagnetic particles in the region spaced from the path of movement of the vanes.

According to another aspect of the invention, the trapping device comprises a recess for retaining contaminant particles formed in one of the vane chamber walls outside the area of the vane chamber wall past which the vane passes during pivotal movement of the vane;
and a lid means for allowing contaminant particles to be removed from the housing means while the vanes are positioned to retain a majority of the fluid within the vane chamber.

According to yet another aspect of the invention, a shielding device is provided for shielding the contaminant particulate retention recess from turbulence generated by the movement of the vanes.

The present invention extends the useful life of rotary actuators by reducing damage to seals, vane chamber walls and other components caused by wear particles which may be present within the rotary actuator. The contaminant particles are collected and retained in an area within the housing which is spaced from the areas of contact which occur between the relatively moving components.
Maintenance is also simplified since accumulated contaminant particles can be removed from time to time without disassembling the entire rotary actuator and without draining large amounts of fluid from the system.

Referring in conjunction with FIGS. 1 and 2, a rotary actuator 11 of the type in which the present invention may be practiced generally has a housing 12 defining an internal vane chamber 13. As shown in FIG. In this embodiment, the housing 12 has a cylindrical body member 14 and first and second annular end plates 15, 16, respectively, coaxially positioned. Such parts are secured together by suitable devices, such as bolts 17, for example. A relatively rotatable actuator shaft 18 is disposed along the axis of rotation 19 of the rotary actuator 11 and extends from each end of the housing 12 through each end plate 15,16. The vane chamber 13 defined by the housing 12 and the actuator shaft 18 therefore has an annular shape.

Vane chamber 13 is divided into variable subchambers 13A and 13B by a divider member 21 fixed to body member 14 and extending radially inwardly into contact with actuator shaft 18. ing. A closed loop seal 23 seals the actuator shaft 18, body member 14 to the bulkhead member 21 to prevent fluid leakage.
and extends along the line of contact between the first and second end plates 15, 16, respectively.

The division of the vane chamber 13 into variable sub-chambers 13A, 13B is achieved by means of a plurality of subchambers 13A, 13B that are fixed to the actuator shaft 18 and extend radially from the actuator shaft 18 into contact with the inner surface of the body member 14. This is completed by the existing vanes 24.
Another closed loop seal 27 attached to the vane 24 is attached to the line of contact between the body member 14, the actuator shaft 18 and the first and second end plates 15, 16, respectively, to the vane 24. It extends along. Therefore, by introducing pressurized fluid into one of the auxiliary chambers 13A, 13B and simultaneously discharging the fluid from the other auxiliary chamber, the vane 24 is connected to the housing 1.
2, the actuator shaft 18 can be caused to perform a pivoting movement such as to rotate the actuator shaft 18 relative to the actuator shaft 18. A port device 28 for this purpose includes first and second flow passages 29, 30, respectively, in the second end plate 16. Channels 29, 30 communicate with the vane chamber 13 on both sides of the partition member 21, and are adapted to be connected to a source of pressurized fluid via control valves in a known manner.

One or both ends of the actuator shaft 18 may be provided with threads 31 or other suitable devices for communicating with a first mechanical member 32 and the housing 12 may be provided with another mechanical member 34 and a rotary actuator. Devices such as perforated ears 33 may be provided in this embodiment for connecting the holes 11 to 11. Mechanical members 32, 34 are structural members adapted for controlled and limited rotary movement between each other. For example, when used in the above-mentioned excavator, the first mechanical member 32 to which the actuator shaft 18 is connected is generally a movable link device that supports a digging member, and the movable link device is a rotary The actuator 11 is operated to swing around a vertical axis of rotation. Second
The mechanical member 34 is the frame of the vehicle. In other cases, the housing 12 may be coupled to a movable member,
Actuator shaft 18 may be connected to a fixed member.

With particular reference to FIG. 2, in those cases where the movement of vane 24 is not limited by a mating external mechanism to which rotary actuator 11 is connected, an internal stop device 37 for such limitation is provided. can be provided. For example, shoulders 35 , 35 on opposite sides of bulkhead member 21 cooperate with shoulders 36 , 36 on opposite sides of vane 24 to direct the pivoting movement of vane 24 into a predetermined fan shape within vane chamber 13 . It will be appreciated that the stop device 37 can be formed to limit the area. Then, when said pivoting movement also reaches its respective terminal end, the vane 24 moves into the subchamber 1.
3A cannot be moved through the end region 38A, nor can it be moved through the end region 38B of the subchamber 13B. The dirt trap 39 includes first and second traps 39A, 39B and a vane 2.
4 to trap contaminant particles in the fluid in the vane chamber 13 located remote from the path of motion of the vane chamber 13;
End regions 38 of the subchambers 13A and 13B, respectively.
A, 38B.

Referring now to FIGS. 2 and 3 in conjunction, the first trap device 39A has an end region 38A outside the portion of the subchamber 13A through which the vane 24 passes.
The first end plate 15 includes a recess 41A formed in the first end plate 15 for holding contaminant particles. In the embodiment of the present invention, the recess 41A for retaining contaminant particles is located in the first end plate 15 because the rotary actuator 11 in this case has its rotation axis 19.
The first end plate 15 of the two end plates 15, 16 is designed to be used in a lower position. It is from.
The recess 41A for holding contaminant particles is the vane chamber 13.
It is advantageous if the rotary actuator 11 is arranged at the bottom of the rotary actuator 19 , where it may be arranged differently in the opposite end plate 16 if the rotary actuator 11 assumes different orientations in use, or the rotation axis 19 If it is horizontal, it may be provided on the inner wall of the body member 14.

Due in part to the action of gravity, contaminant particles within the rotary actuator fluid collect in contaminant particle retention recess 41A. Collection and retention of contaminant particles, which tend to be ferromagnetic, is also aided by a magnetic device 42A located within contaminant particle retention recess 41A. In this embodiment, an access passage 43 provided in the end plate 15
A extends from the contaminant particulate retention recess 41A to the outside of the housing 12 and is normally closed by a removable lid device 44A. In this embodiment, the closure device 44A includes a plug 46 that threadably engages within the access passageway 43A.
It is A. In this embodiment, magnetic device 42A is a cylindrical permanent magnet 47A fixed to plug 46A. Permanent magnet 47A extends into sump recess 41A when lid device 44A is engaged within access passage 43A.

The contaminant particles accumulated in the contaminant particle retaining recess 41A are retained by a shielding device 48A that shields the contaminant particle retaining concavity 41A from the turbulent flow generated by the movement of the vane 24. Then,
Further subsidies will be provided. A shield member 49A, preferably formed of a non-magnetic material such as brass, aluminum or a suitable plastic, is located furthest away from vane 24 and is loaded with a permanent magnet 47A. It is arranged to cover the recess 41A for holding contaminant particles.
The shielding member 49A is spaced apart from the surface of the end plate 15 by a small distance. The shielding member 49A has a downwardly angled edge adjacent the inner surface of the body member 14 and contacting the end plate 15. The edge is attached to the first end plate 15 by a screw 51A to the shielding member 49A.
It is possible to fix it.

The second trap device 39B is of substantially similar construction except that it is located within the end region 38B of the antechamber 13B. The end region 38B is at the opposite end of the rotation of the vane 24 and is outside the path of movement of the vane 24. Therefore, the trap device 39B is connected to the first trap device 39B.
A shielding member 4 similar to the part corresponding to A
a second contaminant particle retention recess 41B partially covered by a shielding device 48B comprising 9B;
and a permanent magnet 47B provided within the shielded area of the second contaminant particulate holding recess 41B;
A lid device 44B is included.

The above-described embodiment of the invention is designed for use in a device for pivoting relative to a vehicle supporting the movable member of the attachment on a backhoe about a vertical axis. In this case, the movable backhoe member, which is the first mechanical member 32, is connected to the actuator shaft 18, and the housing 12 is connected to the second mechanical member via the ear portion 33.
It may also be connected to a frame member, which is a mechanical member 34. Hydraulic fluid such as oil is transferred to port device 2.
8 into one of the channels 29, 30 and draining the other channel back into the tank.
Actuator shaft 18 is rotated about a vertical axis of rotation 19 as a result of differential pressure on opposite sides of vane 24 . Each mechanical member 32, 34 thereby closes the flow of fluid entering or exiting the port device 28.
They can be held oriented at selected angles between each other. This is because fluid is then unable to escape from either of the antechambers 13A, 13B as necessary to allow such angular movement.

Although the present invention has been described for illustrative purposes as being used in connection with a bucket hoe attachment, it will be appreciated by those skilled in the art that it may be used in any other manner in which the rotary actuator 11 is used in substantially the same manner. It will be clear that there are many types of devices.

When the rotary actuator 11 is used for a certain period of time, contaminant particles present in the vane chamber 13 that are continuously carried into the vane chamber 13 by more or less inflowing hydraulic fluid. Particulates are collected in contaminant particulate retention recesses 41A, 41B, in part by the action of gravity. In the large and low equipment, contaminant particles, which are mainly ferromagnetic materials, are removed from the recess 41A for holding contaminant particles.
Collecting and holding within magnet 4
7A, 47B. Retention of accumulated contaminant particles is achieved by shielding members 49A, which reduce turbulence around the contaminant particle retention recesses 41A, 41B around the magnets 47A, 47B.
It is also subsidized by 49B.

For example, the body member 14 and the end plate 1
5, 16 and closed loop seal 27 for vane
contamination in contact areas between relatively moving members, such as between the bulkhead member closed-loop seal 23 and the actuator shaft 18; Trapping device 39 for fine particles
The more such material is collected and kept away from the contact area, the more abrasive wear on such parts is reduced and the life of the rotary actuator is increased.

In addition to directly reducing the deleterious effects of contaminant particles within the rotary actuator 11, the present invention also makes periodic cleaning much simpler and easier since it does not require disassembly of the entire system for periodic cleaning. That is, periodically, accumulated contaminant particles can be easily removed by simply unscrewing the plug 46 when the port assembly 28 is not pressurized. When the plug 46 is removed from the access passage 43, accumulated ferromagnetic particles that are attached to the magnet 47A of the lid assembly 44 are also removed at the same time. Also, the flow of some fluid through the access passage 43 following removal of the plug 46 aids in cleaning by washing away non-magnetic particles that may not have attached to the magnet 47A. In this case,
It is not necessary to drain the entire volume of the vane chamber 13 for cleaning. Before removing one of the plugs 46, the rotary actuator 1
1 can be operated to pivot the vanes 24 to the point of movement closest to the recesses 41A for the contaminant particles to be cleaned. In this state, most of the fluid in the entire volume of the vane chamber 13 is drawn through the vanes 24.
4, so that only a relatively small portion is allowed to flow out when the lid assembly 44 is opened. When the lid assembly 44A is replaced and closed, the rotary actuator 11 rotates the vane 24 to the opposite end of its travel, after which the other lid assembly 44B is temporarily removed to allow the second lid assembly 44B to be opened.
The contaminant particle retention recesses 41B can be cleaned in a similar manner with minimal fluid escape from the rotary actuator 11.

Other aspects, objects, and advantages of the present invention will be apparent from a review of the accompanying drawings, description, and utility model claims.

[Brief explanation of the drawing]

FIG. 1 is an elevational view of a rotary actuator including an embodiment of the present invention, with portions of the structure cut away to show the internal components of the device. Figure 2 is the first
Fig. 3 is a cross-sectional view of the rotary actuator taken along the - line in Fig. 2; Fig. 3 is a partial sectional view of the rotary actuator along the - line in Fig. 2; The appropriate structure of is shown. 11...Rotary actuator, 12...
Housing (housing device), 13... Vane chamber (chamber), 13A, 13B... Sub-chamber, 15, 16
...End plate (end member, member), 18...
... Actuator shaft, 19 ... Rotation axis (axis), 24 ... Vane, 28 ... Port device,
38A, 38B... End area (area), 39, 3
9A, 39B... Trap device, 41A, 41B
...Recess for holding contaminant particles, 42A...Magnetic device, 43, 43A...Access passage, 44, 44
A, 44B...Lid device (removable lid device), 47A, 47B...Magnet (magnet member), 48
A, 48B... Shielding device, 49A, 49B... Shielding member.

Claims (1)

[Claims for Utility Model Registration] (1) Housing device 12 defining vane chamber 13
an actuator shaft 18 extending into the vane chamber 13 and rotatable relative to the housing device 12;
a vane 24 located within the actuator shaft 18 and extending radially from the actuator shaft 18, the vane 24 discharging a fluid corresponding to the displacement of the vane chamber 13 by pivoting between opposite end positions of the vane; Pressurized fluid enters and exits the vane chamber 13 via a flow path opening into the vane chamber 13 to pivot the vane 24 relative to the housing arrangement 12 and rotate the actuator shaft 18. a port device 28 for causing contaminant particles of the pressurized fluid to flow within the vane chamber 13 and to the vane 2.
Area 38A or 38 outside the range of pivot movement of 4
B has a trap device 39 which is held in the housing device 12.
at least a pair of mutually spaced apart contaminant particle retention recesses 41A, 41B formed in the vane chamber 13 and open to the vane chamber 13, the first of the recesses 41A, 41B; 41
A is adjacent to one end of the range of pivoting movement of the vane 24, and the other of the recesses 41B is adjacent to the other end of the range of pivoting movement of the vane 24; A rotary actuator featuring: (2) The rotary actuator according to claim 1, wherein the trap device 39 includes a magnetic device 42A that magnetically holds ferromagnetic particles in the region 38A. (3) The trap device 39 is a rotary actuator according to claim 1, wherein the trap device 39 includes a shield device 48A that shields the region 38A from turbulence generated by the movement of the vane 24. Eta. (4) The rotary actuator according to claim 1, wherein the trap device 39 includes a removable lid device 44 that allows the contaminant particles to be removed from the area 38A. . (5) at least one of said removable lid devices 44;
The rotary actuator according to claim 4, wherein the part is a magnet 47A. (6) The housing device 12 has the vane chamber 13
having mutually spaced members 15, 16 forming opposite walls of the actuator shaft 18, the actuator shaft 18 extending between the mutually spaced members 15, 16; Furthermore, the trap device 39 has a sump recess 41A formed in one of the mutually spaced members 15, 16, the sump recess 41A spaced apart from the path of movement of the vane 24. The region 38A communicates with the vane chamber 13,
A rotary actuator according to claim 1 of the utility model registration claim. (7) The vane chamber 13 includes variable capacity sub-chambers 13A and 13B arranged on both sides of the vane 24.
and the housing arrangement 12 is further adapted to allow the vane 24 to remove the contaminant particulates from the housing arrangement 12 when the vane 24 retains fluid within one of the antechamber 13A, 13B. including a lid device 44 for
A rotary actuator according to claim 6 of the utility model registration claim.