JPS61105303A - Rotary actuator - Google Patents

Abstract

A rotary actuator includes a housing (10, 12) defining an opening, an output shaft (15) extending through the opening, a stator vane (45) and rotor vane (42) associated with the output shaft (15) and opening to define a plurality of actuation chambers (54...57) and an inner surface of the hosing (10,12) extending inwardly past a shoulder portion of the output shaft (15) to seal directly against the shaft (15).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to rotary actuators, and more particularly to vane-type rotary actuators having a new device for sealing a pneumatic working chamber.

BACKGROUND OF THE INVENTION Rotary actuators generally rotate an output shaft through a predetermined arc at a relatively high instantaneous torque and at a relatively slow speed. A vane-type rotary actuator has a housing defining a chamber, a drive shaft extending from the chamber, and at least one stator vane and rotor vane defining a plurality of working chambers. A one-vane rotary actuator includes one stator vane connected to the inner surface of the cylindrical wall;
It has one rotor page 7 connected to a rotating output shaft.

By selectively introducing and discharging pressurized air into the chamber formed between the vanes, the output shaft is rotated and this rotational movement drives the desired equipment. The rotary actuator of the vane 11[,'j1 is structurally limited to movement through an arc smaller than 3600 degrees.

The two vane rotary actuator has two stator vanes and two rotor vanes, defining a pneumatically actuated chamber between each vane. A two vane rotary actuator produces significantly more torque at a given pressure.

The disadvantage of a two-vane rotary actuator is the arc of rotation.
1iso0J: Limited to very small angles.

The goal in the design and manufacture of all vane-type rotary actuators is to provide an effective seal between the working chambers, minimizing leakage of fluids such as air between the compartments. A major problem area encountered in manufacturing vane-type rotary actuators is the output shaft, rotor and stator vane shield end cap interface. In current rotary actuators, this seal is achieved by providing an annular end canope seal member within an annular groove in the end cap and a portion of the output shaft and the hystator and hero! - Seal between the vane seal and part of the vane seal. This end cap knoll uses a seal with a cross-section such as a ring or a square with rounded corners. This creates a small annular opening between the actuating chambers, creating leakage. This reduces the efficiency of the actuator. In some known designs, a portion of the rotor vane seal contacts the end cap knoll, which essentially results in contact between the seal members;
Rubber to rubber or fly elastomer to elastomer contact. This contact creates drag-breaking forces or significantly reduces the force for starting the vane, significantly shortening seal life.

Therefore, the vane type rotary actuator is equipped with a new sealing device to reduce the drag force and extend the knoll life.
There are many requests to prevent leakage between actuator members.

Problems to be Solved by the Invention The present invention provides a vane-type rotary actuator member,
Overcomes known drawbacks and provides significantly better sealing between working chambers. The preferred structure of the present invention eliminates all comb-to-rubber and elastomer-to-elastomer contact. This significantly reduces drag forces and increases seal life. Furthermore, the present invention/sill device substantially eliminates leakage and the chamber of the actuator is airtight, increasing the efficiency of the actuator.

SUMMARY OF THE INVENTION The rotary actuator of the present invention eliminates the annular groove and annular seal of end caps conventional in known designs. With the invention, the shoulder of the output shaft directly contacts the inner surface of the end wall. To provide this seal, the inner surface of the end cap extends inwardly from a portion of the output shaft such that the shoulder of the shaft directly contacts and seals into engagement.

The inner edge of the inner surface of the cap is cantilevered to provide limited flexibility. The inner surface thus contacts the shoulder of the output shaft in a sealing relationship.

In accordance with the present invention, lip seals are formed on the stator and rotor seals and a means is provided to prevent undesired contact between the lip edges of the seal members during operation. In a preferred example,
The stop member is a protrusion or bumper on one of the faces of the stator or rotor seal.

OPERATION The vane-type rotary actuator according to the present invention reduces drag forces, increases seal life, and minimizes leakage between actuating members.

The vane-type rotary actuator sealing device of the present invention eliminates rubber-to-rubber and elastomer-to-elastomer contact.

In a vane-type rotary actuator according to the present invention, the shoulder of the output shaft and the edges of the stator and rotor vane seals all sealingly engage the inner surface of the end cap.

The vane-type rotary actuator according to the present invention has a lip seal surrounding the stator and rotor vanes, and is further provided with a device to prevent interference between the lips of the seal.

Embodiments and drawings illustrating the present invention will be described.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a rotary actuator according to the invention in which the housing has a cylindrical member 10, two end caps 11, 12 and shows the end 16 of the output shaft, and FIG. 2 shows a rotary actuator according to the invention. It is a developed view of the , showing each internal part. As shown, the cylindrical member 10 is between the end caps 11, 12 and has a Y-cylindrical opening 24 extending longitudinally therethrough. Inside the cylindrical opening 24 are two sets of stator-seal assemblies 25°2.
Install the stator vane consisting of 6. Sol assembly 2
5.26 engages the cylindrical inner surface of the aperture 24 and extends diametrically opposed and radially inwardly toward the output shaft 14.

The end caps 11, 12 each have an annular groove 6 on the inner surface near the outer edge. Groove 66 receives a conventional Q IJ ring 22 or other sealing member to provide a sealing relationship between end cap 11.12 and the end surface of cylindrical member 10. - A plurality of openings 29 are provided in each end portion 11, 12 to provide a set screw 3;
The end cap 11.12 is coupled in sealing relation to the end surface of the cylindrical member 10 through a connecting member such as 0 or the like. In a preferred example,
A groove 28 having a bi-circular cross section is formed along each corner of the cylindrical member 10. Groove 28 coincides with opening 29 in end cap 11.12 and receives screw 60. The groove 28 can also be provided with an internal thread and a self-screwing screw 30 can be screwed into it. The cylindrical member 10 is preferably made of a light alloy, such as aluminum, but may also be made of other materials, including synthetic resins.

The output shaft 14 is located at the center of the cylindrical opening 24 and protrudes from the cylindrical member 10. The central portion 15 of the output shaft has a large diameter and the end portions 16 have a small diameter and project outwardly from both ends along the longitudinal axis. Two shoulders 18 connect the central part 15 and the ends 16.

The annular surface of each shoulder 18 is perpendicular to the longitudinal axis of shaft 14.

The two rotor vanes are part of the rotor seal assembly 19.2
0 and are mounted diametrically opposed to each other along the longitudinal axis at the central portion 15 of the output shaft 14. As shown in FIG. 3.4.6.10, each rotor vane seal assembly includes a rigid mounting element 42 and a rigid lip seal member 44. A rigid mounting member 42 secures the member 42 within the longitudinal slot 41 of the central portion 15 of the output shaft by any desired means, such as gluing or press fitting. FIG. 10 shows a view of the lip seal member 44. Member 44 has an inner rectangular opening 50'f which is secured over mounting member 42. A protrusion or bumper 21 is provided on the outer surface of each lip seal member 44 to allow contact with the side surface of the stator seal. Bumper 21 limits the rotational movement of output shaft 14 and protects rotor seal 19.20 and stator seal 25.
26 to prevent undesired contact between the lips. The lip seal member 44 is connected to the mounting member 42 and is further connected to the central portion 15.
It is fixed by the required adhesive or vulcanization process. When assembled, the lip of each seal member 44 forms a sealing relationship with the inner surface of the cylindrical opening 24 and the inner surface of the end cap 11.12. The lip seal member 44 can be made of various materials, but in a preferred example, the seal member 44 is made of artificial rubber, trade name Buna N.As shown in Figures 4.5 and 11.12, each stator vane seal assembly is 25 and 26 consist of an inner support member 45 and an outer lip seal member 46 integrally formed with the cylinder 10.

Support members 45 are diametrically opposed and extend longitudinally along the inner surface of cylindrical opening 24 . As shown in FIG. 5, both ends of the support member 45 do not extend to the end face of the cylinder 10, but are spaced inwardly to engage the lip seal member 46. The shape of the lip seal member is shown in FIGS. 4 and 11. The lip seal member 46 has a central groove 51 adapted to the shape and dimensions of the support member 45.
The member 46 covers and is fixed to the support member 45. Seal 46 is held in this position by shaft 15. Any desired adhesive or the like may also be used. When in the assembled position, the lip of the seal 46 contacts the inner surface of the opening 24 and the shaft 14.
forming a sealing relationship with the central portion 15 of the end cap 11.12 and the inner end surface of the end cap 11.12.

The structure of the end cap 11.12 is 1.7,8°9.1
Shown in Figure 3. Each end cap 11.12 is provided with a plurality of openings 29 for attaching the end cap 11.12 to the cylindrical member 10. Each end cap 11, 12 is provided with two openings or boats 39, 40 in the inner surface 38 at a position shown in FIGS. As shown in Figure 7, each port 39.40
connects directly to the supply exhaust port 64 by passages 48,49. As shown in FIG. 2.9.13, the inner surface 68 of each end cap 11.12 extends inwardly toward the axis 14;
A circular opening 33 is formed in the center.

The portion of the inner surface 68 that contacts the opening 66 forms the inner surface of the annular portion 32 . Annular portion 32 extends radially inwardly from the body of the end cap and defines an opening 66 at the inner edge. The inner surface of the annular portion 62 forms a sealing surface that engages the shoulder 18 of the shaft 14.

A large diameter hole 31 is formed in each end cap, and a bearing member 35 is formed.
Install. In the preferred embodiment, the bore 31 extends inwardly to the annular portion 62 and has a diameter D3 in FIG. Diameter D3 is larger than the central portion 15 of the shaft so that the annulus 32 flexes slightly when the shoulder 18 of the shaft is engaged. Bearing 35
is press-fitted into the hole 31 to provide a central opening and rotatably support the end portion 16 of the output shaft 14 . Dimension D2 shown in FIG. 16 is the radial dimension of the annular portion 62, and dimension D1 is the longitudinal dimension of the annular portion 32.

To obtain the advantages of the present invention, the diameter of the inner edge or opening 63 of the annular portion 62 is slightly larger than the diameter of the end 16 of the shaft 14 and smaller than the diameter of the central portion 15. by this,
The end 16 is free to rotate within the opening 36 and the shaft shoulder 18 engages the inner surface of the annulus 62 in sealing relation during assembly. This relationship is shown in Figure 5.6.

According to a preferred embodiment, the central portion 15 of the shaft 14 is slightly longer than the length of the cylindrical member 10. End cap 11.12
When assembled into the cylindrical member 10, the annular portion 6 extends inwardly.
2 closely abuts the shoulder 18 and forms a sealing relationship between the shoulder 18 and the annular portion 62. In a preferred example, the length of the cylindrical member 10 is approximately 1.7611r1 (approximately 44")' L, and the central portion 15
0.0051n (approximately 0.13"). Because of this length difference, the end caps 11.12
The annular portion 32 flexes slightly when fixed to the holder. It is necessary to allow the annular portion 62 to flex. Although the annular portion 32 can be of various dimensions, in a preferred embodiment the longitudinal dimension D1 of the portion 62 is smaller than the radial dimension D2. The annular portion 62 is made of a material that allows this bending. Although it can be made of a variety of materials, in a preferred embodiment the end camp is made of a hard synthetic resin, such as nylon.

During assembly, the shaft 14 and rotary seal assembly 19-20 are inserted into the cylindrical opening 24 of the cylindrical member 10.

Insert the O-ring 22.22 into the groove 66 on the inner surface of the end cap 11.12 and tighten the end cap 11.1 with the screw 60.
2 is fixed to the end face of the cylindrical member 10.

When the screw is tightened, the inner surface of the annulus 2 is pressed into sealing relation to the shoulder 18 of the shaft 14, as shown in FIGS.

Once assembled, a plurality of working chambers are formed within the cylindrical member 10 between each stator and rotor vane. This room 54
, 55, 56, and 57 are shown in FIG. During operation of the rotary actuator, the pressurized fluid (e.g. air) 39, 40.
It is fed and discharged via the respective feed and discharge opening 34. Pressurized fluid is supplied to ports 39,40 and openings 64 in end cap 12.
4, the shaft 14 rotates counterclockwise in FIG. Bumper 21 and stator seal 46! :(
7) When the shaft reaches the limit of counterclockwise rotation due to the W touch, the chamber 55.57 is moved to the port 69°4 by the required valve operation.
0, the opening 64 is vented through the end cap 12.

Opening 34 in end cap 11. Ports 39.40 communicate with working chambers 54.56. When pressurized air is supplied to this chamber, the shaft rotates clockwise.

As shown in FIGS. 5 and 6, the side edges 44.46 of the rotor and stator seal members and the shoulder 18 of the shaft 14 sealingly engage the inner surface 38 of the end cap 11.12. Furthermore, the inner edge of the stator seal member 46 shown in FIG.
It is related to the seal. This combined sealing relationship prevents rubber-to-rubber contact, reduces leakage between each actuating chamber, and improves actuator efficiency.

The present invention can be modified in various ways other than the embodiments described above.

For example, FIG. 14 shows a modified example. The end cap assembly includes an end cap support member 60 and an end cap seal plate 6.
It also becomes 1. In this example, a groove is formed in the end surface of the cylindrical member 10 to engage the 01J7 groove 64 and seal against the inner surface of the plate 61. Plate 61 extends beyond central hole 31.

This forms an inwardly extending annular portion 65 in sealing relation to the central portion 15 of the shaft. Both ends 16 of the shaft are rotatably supported by bearings 35 .

Instead of using another end cap or a cylindrical member, a modification example shown in FIG. 15 can be made in which the entire cross section of the plurality of working chambers is semicircular, semielliptical, or the like. In this example, Q IJ 71
is provided between the two no-using parts 66°68. The output shaft has a central portion 15 and two end portions 16 . Two rotor seals 69, a support member 70 are connected to the central part of the shaft 15 and fit into the inner surface of the nozzle 66,68. The inner surfaces formed by portions 66 and 68 are symmetrical and include an inner steel annulus 32 for sealing engagement with the central portion of the output shaft.

The examples are illustrative and do not limit the invention.

[Brief explanation of the drawing]

1 is a perspective view of a rotary actuator according to the present invention, FIG. 2 is an exploded perspective view of the actuator of FIG. 1, FIG. 6 is an exploded perspective view of the output shaft of the actuator, and FIG. An enlarged sectional view along line 4, Figure 5 is 5-5 in Figure 4.
6 is a sectional view taken along line 6-6 in FIG. 4, FIG. 7 is an end view with a portion of the inner surface of the end cap removed, and FIG. 8 is an outer surface of the end camp. 9 is a sectional view taken along line 9-9 in FIG. 8, FIG. 10 is a perspective view with a portion of the rotor seal removed, and FIG. 11 is a perspective view with a portion of the stator seal removed. , FIG. 12 is an end view of the cylindrical member excluding the stator seal, FIG. 13 is a partial enlarged cross-sectional view of a portion of the end cap, and FIG. 14 is a partial cross-sectional view of an actuator according to a modification of the present invention. FIG. 15 is a sectional view of a portion of an actuator according to another modification. 10 Cylindrical member 11.12 End cap 14 Output shaft 15 Shaft center portion 16 Shaft end portion 18 Shoulder portion 19, 20 Rotor seal assembly 21 Bumper 22 O-ring 24 Cylindrical opening 25.26 Stator seal 31 Large diameter portion 62 Annular portion 33.34 Open 0. 59.40 Boat 41 Slot 42 Mounting member 44.46 Rib seal member 45 Support member (5 others) Procedures Amendment letter e Otsu () 1985 / January 2-L day 1, Showa Otsu O year Patent application No. /1y10≠O No. 2, title of invention ci: J 剌, 1f + 1 eta 6, relationship with the case of the person making the amendment Patent applicant address Gf:r:)+Shi Fang--Mf7f・I/Coordinate. 4. Buried person

Claims (1)

[Scope of Claims] 1. A rotary actuator, comprising a housing having a substantially cylindrical opening, both sides of the opening forming a cylindrical inner surface, and the end having two mutually spaced and substantially parallel end surfaces. with the end faces extending inwardly toward the central opening; a central axis passing through the cylindrical opening; the central portion of the shaft being within the cylindrical opening; and the two ends extending from both ends of the central portion along the longitudinal axis. extending outwardly through the central aperture along the central portion, the diameter of each end of the central portion being greater than the diameter of the end portion and greater than the diameter of the central aperture, and the diameter of the end portion being less than the diameter of the central aperture; a shoulder is formed between the central portion and the end portion of the shaft for sealing engagement with a portion of the inner end portion surrounding the central opening; a first vane member having a mating first sealing device; a second vane member having a second sealing device coupled to the central portion of the shaft and sealingly engaging the end face and the cylindrical inner surface; A rotary actuator comprising two working chambers formed between first and second vane members, and a device for introducing and discharging pressurized fluid into the working chambers. 2. The actuator of claim 1, wherein the housing includes two spaced apart end caps having the end faces and the central opening. 3. Each end cap has an outer surface substantially parallel to the end surface;
A patent characterized in that a large diameter portion extends inwardly along the same axis as the central opening from the outer surface toward the end surface, and the diameter of the large diameter portion is larger than the diameter of the end of the central portion of the shaft. An actuator according to claim 2. 4. The actuator according to claim 3, further comprising a bearing rotatably supporting the end of the mounting shaft within the large diameter portion of each end cap. 5. The housing has a tubular member between the end caps, and the length of the tubular member is smaller than the length of the central portion of the shaft to create a sealing force between the shoulder and the end face after assembly. An actuator according to claim 2, characterized in that: 6. The actuator according to claim 5, wherein the end cap is made of a synthetic resin material. 7. The actuator according to claim 6, wherein the end cap is made of nylon. 8. Each shoulder portion is provided with a generally annular surface extending between the central portion and the end portions and sealingly engaging an end surface portion surrounding the central opening. Actuator described in section. 9. The actuator according to claim 1, wherein the first and second seal devices are lip seal devices. 10. The actuator according to claim 9, wherein at least one of the first and second lip seal devices is provided with a protrusion to prevent interference between the first and second lip seal devices. 11. A rotary actuator, comprising: a housing having a chamber defined by an inner surface; and two shaft openings at opposite ends of the chamber;
a shaft having a central portion within the chamber, two ends extending outwardly from the shaft opening, and a shoulder joining the central portion to the shoulder, the diameter of at least both ends of the central portion being connected to the shaft opening and the shaft; larger than the diameter of the ends, and each shoulder has a generally annular surface extending between the center and the ends for sealing engagement with an inner surface surrounding the shaft opening; a first vane having a first sealing device in sealing engagement with the central portion; a second vane having a second sealing device connected to the central portion of the shaft and sealingly engaging the inner surface; A rotary actuator comprising at least two working chambers formed between the vane member and a device for selectively introducing and discharging pressurized fluid into the working chambers. 12. The actuator according to claim 11, wherein the chamber is symmetrical and has an axis of symmetry, and the shaft opening is coaxial with the axis of symmetry. 13. The housing is provided with a large diameter portion spaced outward from each shaft opening and coaxial with the axis of symmetry, and the diameter of the large diameter portion is larger than the diameter of both ends of the shaft center portion. An actuator according to claim 12. 14. Claim 1, further comprising a bearing rotatably supporting the end portion of the mounting shaft within the large diameter portion.
The actuator according to item 3. 15. The actuator according to claim 11, wherein the housing is made of a synthetic resin material. 16. The actuator according to claim 15, wherein the housing is made of nylon. 17. The actuator according to claim 11, wherein the first and second seal devices are lip seal devices. 18. At least one of the first and second lip seal devices is provided with a protrusion to prevent interference between the edges of the first and second lip seal devices. actuator.