JP3432766B2 - Linear actuator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention makes it possible to reciprocate a slide table along the axial direction of an actuator body by introducing a pressurized fluid from a fluid inlet / outlet port. Related to simple linear actuators. 2. Description of the Related Art Conventionally, a linear actuator has been used as a means for transporting a work or the like. This linear actuator can convey a work placed on the moving table by reciprocating the moving table linearly along the body. FIGS. 9 and 10 show a fluid pressure actuator of this type according to the prior art (Japanese Patent Laid-Open No. 11-5100).
No. 9). The fluid pressure actuator 1 according to the prior art has a body 2 formed in a substantially rectangular parallelepiped shape, and one side surface of the body 2 has two substantially parallel strips for mounting a magnetic proximity sensor 3. The sensor mounting rail 5 in which the mounting groove 4 is formed is provided. This sensor mounting rail 5 is
Bolt 6 inserted into a set of holes (not shown) that are spaced apart
Is screwed into a screw hole (not shown) formed on one side surface of the body 2 to be fixed to one side surface of the body 2. FIG. 11 shows another conventional hydraulic cylinder (see Japanese Utility Model Laid-Open No. 6-43302). The fluid pressure cylinder 7 has a cylinder chamber (not shown) provided therein, a cylinder body 9 having an end block 8 connected to one end thereof, and a linear guide 10 fixedly mounted on the upper surface of the cylinder body 9. And a table 11 that moves along the axial direction of the cylinder body 9 under the guide action of the above. A first overhanging portion 12 is formed to bulge upward at one end of the cylinder body 9 substantially perpendicular to the longitudinal direction, and the first overhanging portion 12 is sandwiched on one side surface of the table 11. The second overhanging portion 13 and the third overhanging portion 14 are formed to bulge in the lateral direction. In this case, bolts 15a screwed into the second overhang 13 and the third overhang 14, respectively,
15b comes into contact with the first overhang portion 12,
The movement end position of the table 11 is regulated, and the amount of movement of the table 11 is adjusted by adjusting the screwing amount of the bolts 15a and 15b. However, in the fluid pressure actuator 1 according to the prior art described above, it is necessary to form a hole for bolt insertion in the sensor mounting rail 5, and the diameter of the hole is required. There is a disadvantage that the dimension in the height direction of the sensor mounting rail 5 is increased by that much, and the dimension in the height direction of the entire apparatus is increased. In another conventional hydraulic cylinder 7, a bolt 15 for restricting the amount of movement of the table 11 is provided.
a, 15b to the second overhang 13 and the third overhang 14
Since the table 11 is provided in the lateral direction (width direction) of the table 11, the size of the table 11 in the width direction is increased, and the size of the entire apparatus in the width direction is disadvantageously increased. In this case, a convex portion (not shown) is formed on the upper surface of the substantially central portion of the end block 8 connected to the cylinder body 9 so as to bulge, and a bolt 15a (15) screwed into the convex portion is formed.
It is conceivable that the amount of movement of the table 11 is regulated by b). However, by connecting the end block 8 to one end of the cylinder body 9, the axial dimension of the cylinder body 9 increases, and the axial length of the entire apparatus is increased. There is another disadvantage that the dimensions are increased. In the fluid pressure cylinder 7, the cylinder body 9 and the end block 8 may be integrally formed by casting or the like.
When polishing is performed using a polishing grindstone (not shown) to form a ball rolling groove on the side surface of the end block 8, the end block 8 integrally formed with the cylinder body 9 and the end block 8 are formed to bulge. There is an inconvenience that the projections (not shown) become obstacles and the ball rolling grooves cannot be polished smoothly. SUMMARY OF THE INVENTION The present invention has been made to overcome the above-mentioned various inconveniences, and achieves a reduction in size and weight by suppressing the width, axial direction, and height dimensions of the entire apparatus. It is an object of the present invention to provide a linear actuator capable of performing the above. [0013] In order to achieve the above object, the present invention provides a reciprocating operation of a slide table along an axial direction of an actuator body by introducing a pressurized fluid from a fluid inlet / outlet port. An actuator body having a through hole penetrating along the axial direction and having an opening communicating with the through hole, and a slide table reciprocating along the axial direction of the actuator body. And a joint member which is connected to the bottom surface of the slide table at a right angle through the opening and is displaced integrally with the slide table, and slides along a cylinder chamber formed in the through hole. The joint member is arranged freely along the axis of the actuator body under the action of a pressure fluid. And a sliding mechanism for guiding the slide table along the axial direction of the actuator body ;
The actuator body opposite to the slide table
A projection mounted on a recess formed on the bottom surface of the
Actuator from the bottom of the actuator body
A rail member formed with a long groove for mounting a sensor, the rail member being mounted on the tab body;
Connected to one end along the axial direction of the
Connection provided with displacement adjustment means for adjusting the displacement of the
A connection member, and the connection member is an actuator body .
Projection to be attached to the mounting recess formed on the bottom of b
And a fluid inlet / outlet port communicating with the cylinder chamber was formed.
The protrusion and the block body are composed of a block body.
Characterized Rukoto integrally provided. [0014] According to the present invention, the actuator body
Attach the convex part of the rail member to the concave part formed on the bottom part ,
Securing the rail member to the actuator body by screwing a bolt or the like from the direction of the bottom surface of the actuator body. Therefore, since the hole for bolt insertion is not provided along the height direction of the rail member, the dimension in the height direction is suppressed by the diameter of the hole, and the dimension in the height direction of the entire apparatus is suppressed. You. Further, in the present invention, since the connecting member formed separately from the actuator body and connected to one end of the actuator body along the axial direction is provided with the displacement amount adjusting means, the slide table is provided. It is not necessary to provide a second overhang portion and a third overhang portion in the lateral direction of the slide table, so that the size of the slide table in the width direction is suppressed, and the size of the entire apparatus in the width direction is suppressed. Further, in the present invention, since the end blocks are not connected, the dimension in the axial direction of the entire apparatus is suppressed. Preferred embodiments of a linear actuator according to the present invention will be described below in detail with reference to the accompanying drawings. In FIG. 1, reference numeral 20 indicates a linear actuator according to an embodiment of the present invention. The linear actuator 20 basically has a rectangular parallelepiped actuator body 22 and a straight line extending along a pair of guide blocks 24a and 24b which are formed integrally with the actuator body 22 by swelling on the upper surface of the actuator body 22. Slide table 26 that reciprocates in a shape, and a sliding mechanism 28 that reciprocates the slide table 26 smoothly along the axial direction of the actuator body 22.
It is composed of The actuator body 2
2 is preferably cast and molded by a lost wax method or the like, for example. As shown in FIG. 4, a pair of guide blocks 24a and 24b extending in the axial direction at predetermined intervals are integrally formed on the upper surface of the actuator body 22 so as to protrude. A pair of guide blocks 24
A ball circulation hole 30 and a ball rolling groove 32 to be described later are formed in a and 24b, respectively. As shown in FIG. 2, a substantially columnar joint member 34 (described later) has a substantially elliptical opening 36a for freely displacing the substantially cylindrical joint member 34 (described later) at a substantially central portion between the top surface and the bottom surface of the actuator body 22. , 36b are respectively formed. As shown in FIGS. 1 and 5, mounting holes 38 penetrating through a step are formed in a pair of diagonally opposed corners of the actuator body 22.
a, 38b are formed respectively, and the mounting hole 38
By fitting a fixing bolt (not shown) to the a and 38b, the actuator body 22 can be fixed to another member (not shown), a wall surface, or the like. Further, inside the actuator body 22, as shown in FIG.
b, and a through hole 40 extending in the axial direction is formed, and both ends of the through hole 40 are provided with a pair of end caps 44 a in which a seal ring 42 is mounted in an annular groove,
Each of the end caps 44a is closed airtightly in the through hole 40 via a retaining ring 46. In the through hole 40, a pair of pistons 50 having piston packings 48 mounted thereon through annular grooves.
a, 50b are provided, and the pair of pistons 50a,
Ob is slidably provided along the through hole 40.
A ring-shaped damper 52 made of, for example, urethane rubber is attached to one end of one piston 50a, and a small-diameter fixed member that penetrates the other end cap 44b along the axial direction. An aperture 54 is formed. In this case, a pair of end caps 44a and 44b for closing the through hole 40 and a pair of pistons 50
a, 50b, a set of cylinder chambers 56a, 56b
Are formed, and one cylinder chamber 56a is
As shown in FIG. 5, the first fluid inlet / outlet ports 60a and 60b are provided so as to communicate with each other via the fixed throttle 58. The other cylinder chamber 56b is connected via a fixed throttle 54 of the end cap 44b to a pair of second fluid inlet / outlet ports 64a formed in a connection block 62 described later.
64b are provided so as to communicate with each other. The first fluid inlet / outlet ports 60a, 60a
Ob (second fluid inlet / outlet ports 64a, 64b) is provided with a first port in which a pipe such as a tube is taken out along the axial direction, and a direction in which the pipe / tube taking out direction is substantially perpendicular to the axis. And a second port provided by the operator. By connecting a tube or the like to either the first port or the second port according to the installation environment, the operator can appropriately select the direction in which the pipe is taken out. . In this embodiment, as shown in FIG. 3, the pipe is taken out from a direction substantially perpendicular to the axis, and the first port along the axial direction is a plug screwed into the first port. It is closed by 66. The plug 66 is provided to be screwable into either the first port or the second port. As shown in FIG. 2, a joint member 34 extending substantially vertically is provided between the pair of pistons 50a and 50b, and one end of the joint member 34 is connected to a slide table. 26 is screwed into a screw hole 68 formed substantially at the center. In this case, one cylinder chamber 56a is connected via the first fluid inlet / outlet ports 60a, 60b (or the second fluid inlet / outlet ports 64a, 64b).
The pressure fluid is introduced into (56b), and the pistons 50a, 50
b, the slide table 26 is displaced in the direction of arrow X (or the direction of arrow Y) via the joint member 34 by the end portions of the pistons 50a and 50b abutting against and pressing the joint member 34. Can be done. On the bottom of the actuator body 22,
As shown in FIG. 8, a recess 74 for mounting a sensor mounting rail (rail member) 72 described later is formed through a set of bolts 70, and the recess 7 has a bolt 7.
A set of screw holes 73 for screwing 0 is formed. The bottom of the actuator body 22 has 3
A mounting recess 76 for mounting the connection block 62 via the bolt 70 is formed.
Are formed with three screw holes for screwing bolts. The connection block 62 includes a seal ring 7
A block in which an annular step portion 80 (see FIG. 2) which is air-tightly connected to the end cap 44b through the upper portion 8 is formed, and a pair of second fluid inlet / outlet ports 64a, 64b are formed in directions substantially orthogonal to each other. A body 82 and a long flat plate-shaped projection 84 provided integrally with the side surface of the block body 82 and mounted in the mounting recess 76 of the actuator body 22 (see FIGS. 8 and 9). . The connection block 62 is preferably formed by, for example, extruding aluminum or the like. The block 82 has a screw hole 8 therethrough.
The screw hole 86 has a damper 8 at one end.
The stopper 90 provided with 8 is screwed. The stopper 90 is a displacement adjusting means for regulating the displacement of the slide table 26 when the slide table 26 comes into contact with the stopper 90 and for freely adjusting the displacement under the screwing action of the nut member 92. Act as a function. On the upper surface of the slide table 26, a pair of recesses 98a, 98b to which bent portions 96a, 96b of a bracket 94 to be described later are attached are formed, and the bracket 94 is bent into the recesses 98a, 98b. Part 96
The slide table 26 is fixed to the slide table 26 by attaching the screws a and 96b and screwing the screws 96 through the bolts 100. A guide portion 102 extending along the axial direction is integrally formed on the bottom surface of the slide table 26 so as to bulge out.
Ball rolling grooves 104 each having an arc-shaped cross section are formed on opposing side surfaces of the guide portion 102 so as to extend along the axial direction. Further, as shown in FIG. 2, the slide table 26 is formed with a cutout having a rectangular cross section having a contact surface 106 that comes into contact with the stopper 90. The sliding mechanism 28 is, as shown in FIG.
The vehicle includes a pair of guide blocks 24a and 24b swelled integrally with the actuator body 22, and covers 108 and scrapers 110 respectively attached to both ends of the guide blocks 24a and 24b via screw members. The guide blocks 24a and 24b are formed with ball circulation holes 30 penetrating along the axial direction, and ball rolling grooves 32 extending along the axial direction are formed on inner wall surfaces facing the guide blocks 24a and 24b. Is formed.
The ball circulation hole 30 and the ball rolling groove 32 are provided with a plurality of ball bearings 116 that roll along the ball circulation hole 30 and the ball rolling groove 32. On one side of the sensor mounting rail 72,
Two long grooves 118 for mounting the sensor, each having an arc-shaped cross section, are formed substantially parallel to each other, and a recess 120 having a V-shaped cross section is formed on one side surface opposite to the long groove 118 (see FIG. 4). . The sensor mounting rail 72 has a convex portion 122 having a shape corresponding to the concave portion 74 of the actuator body 22 bulging. The convex portion 122 is attached to the concave portion 74 and screwed with a bolt 70 to secure the convex portion 122. The sensor mounting rail 72 is fixed to the actuator body 22 (see FIG. 8). A bracket 94 for holding a columnar magnet 126 is provided between the actuator body 22 and the sensor mounting rail 72 via a plurality of claw pieces 124. The bracket 94 is fixed to the upper surface of the slide table 26 via a pair of flat bent portions 96a and 96b separated by a predetermined distance, and the magnet 126 is displaced integrally with the slide table 26. (See FIG. 7). The linear actuator 20 according to the embodiment of the present invention is basically configured as described above. Next, the operation and effect of the linear actuator 20 will be described. First, a pressure fluid from a fluid pressure source (not shown) is introduced into the second fluid inlet / outlet port 64b. In this case, the other first fluid inlet / outlet port 60a is kept open to the atmosphere under the switching action of a switching valve (not shown). The pressure fluid is supplied to the second fluid inlet / outlet port 64.
b through a fixed throttle 54 communicating with one of the cylinder chambers 5.
6b, and presses the piston 50b in the arrow X direction. When the piston 50b is pressed and displaced, the end of the piston 50b contacts the joint member 34, and the joint member 34 is displaced in the direction of the arrow X along the openings 36a and 36b. Therefore, the slide table 26 connected to the joint member 34 is displaced in the direction of the arrow X integrally with the joint member 34,
The damper 52 attached to one end of the piston 50a comes into contact with the end cap 44a to reach one displacement end position. The damper 52 allows the piston 5 to move.
The shock at the time when Oa comes into contact with end cap 44a is reduced. When the slide table 26 is displaced in the opposite direction (the direction of the arrow Y), a pressurized fluid is supplied to the first fluid inlet / outlet port 60a. The supplied pressure fluid is introduced into the other cylinder chamber 56a via the fixed throttle 58, and presses the piston 50a in the direction of arrow Y. The joint member 34 is displaced in the direction of the arrow Y under the pressing action of the piston 50a, and the slide table 26 is displaced in the direction of the arrow Y via the joint member 34. In this case, the contact surface 106 formed in the notch of the slide table 26 contacts the damper 88 of the stopper 90 to reach the other displacement end position. In addition,
The shock when the slide table 26 contacts the stopper 90 is reduced by the damper 88 provided at one end of the stopper 90. As described above, in the present embodiment, the protrusion 122 of the sensor mounting rail 72 is mounted on the recess 74 formed on the bottom surface of the actuator body 22, and the bolt 70 is screwed into the actuator body 22. , A sensor mounting rail 72 is fixed. Therefore, since the hole for bolt insertion is not provided along the height direction of the sensor mounting rail 72, the dimension in the height direction is suppressed by the diameter of the hole, and the dimension in the height direction of the entire apparatus is reduced. Can be suppressed. In this embodiment, the connecting block 6
A stopper 90 that regulates the amount of movement of the slide table 26 through the actuator body 22 is provided on the actuator body 22.
Therefore, it is not necessary to provide the second overhang 13 and the third overhang 14 in the lateral direction of the table 11 as in the prior art shown in FIG. 11, so that the size of the slide table 26 in the width direction is suppressed, and as a whole the apparatus. The dimension in the width direction can be suppressed. Further, in the present embodiment, the end block 8 is not connected to one end of the cylinder body 9 as in the prior art shown in FIG. 11, so that the axial size of the entire apparatus can be suppressed. . Further, by forming the actuator body 22 and the connection block 62 as separate bodies, a pair of guide blocks 24a of the actuator body 22 are provided.
Since there is no obstacle when the ball rolling groove 32 formed in 24b is polished by a grinding wheel (not shown), there is an advantage that the ball rolling groove 32 can be polished smoothly. As a result, in this embodiment, the size and weight of the entire apparatus can be reduced by suppressing the height, width, and axial dimensions of the entire apparatus. According to the present invention, the following effects can be obtained. That is, the size and weight of the entire apparatus can be reduced by suppressing the dimensions in the height direction, the width direction and the axial direction of the entire apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a linear actuator according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view taken along line II-II of FIG. FIG. 3 is a transverse sectional view taken along the line III-III of FIG. 2; FIG. 4 is a longitudinal sectional view taken along the line IV-IV of FIG. 2; FIG. 5 is a cross-sectional view showing a sliding mechanism. FIG. 6 is a bottom view of the linear actuator shown in FIG. 1; FIG. 7 is an exploded perspective view of a main part of the linear actuator shown in FIG. 1; FIG. 8 is a view as seen from the direction of arrow Z in FIG. 7; FIG. 9 is a front view of a hydraulic actuator according to the related art. FIG. 10 is a side view of the fluid pressure actuator shown in FIG. 9; FIG. 11 is a perspective view of another conventional hydraulic cylinder. [Description of Signs] 20 Linear actuator 22 Actuator bodies 24a and 24b Guide block 26 Slide table 28 Slide mechanism 30 Ball circulation holes 32 and 104 Ball rolling grooves 34 Joint members 36a and 36b Opening Part 40: Through holes 44a, 44b: End caps 50a, 50b
... Pistons 52, 88 ... Dampers 56a, 56b
... Cylinder chambers 60a, 60b, 64a, 64b ... Fluid inlet / outlet port 62 ... Connecting block 70, 100 ...
Bolt 72 ... Sensor mounting rail 76 ... Mounting recess 82 ... Block body 84 ... Protrusion 90 ... Stopper 94 ... Brackets 96a and 96b ... Bends 74 and 98a
98b, 120: concave portion 102: guide portion 116: ball bearing 118: long groove 122: convex portion 126: magnet

──────────────────────────────────────────────────続 き Continuing on the front page (72) Shogo Miyazaki, Inventor 4-2-2 Kinudai, Yawahara-mura, Tsukuba-gun, Ibaraki Prefecture SMC Corporation Tsukuba Technical Center (56) References JP-A-10-89312 (JP, A) JP-A-10-238508 (JP, A) JP-A-6-47708 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F15B 15/14 F15B 15/24 F15B 15/28

Claims (1)

(57) Claims 1. A linear actuator for reciprocating a slide table along an axial direction of an actuator body by introducing a pressurized fluid from a fluid inlet / outlet port. An actuator body having an opening communicating with the through-hole, a slide table reciprocating along an axial direction of the actuator body, and the slide table through the opening. A joint member which is connected to the bottom surface of the slide table at substantially right angles and is displaced integrally with the slide table; and is slidably disposed along a cylinder chamber formed in the through hole, under the action of a pressure fluid. A set of pistons for pressing the joint member along the axial direction of the actuator body; A sliding mechanism for guiding the table along the axial direction of the actuator body ;
Has a convex portion which is mounted in a recess formed on the bottom surface of the table opposite side of the actuator body, the actuator ball
From the direction of the bottom of the day to the actuator body
Attached Te, a rail member which longitudinal groove is formed for the sensor attached to one end portion in the axial direction of the actuator body
Displacement that is connected and adjusts the displacement of the slide table
A connecting member provided with adjusting means , wherein the connecting member is formed on a bottom surface of the actuator body.
And the protrusion to be attached to the mounting recess
From the block body with fluid communication ports formed
Wherein the projection and the block body are provided integrally .