JP2000240613A - Linear actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce distorsion of shape materials for a base and a sensor mount rail, simultaneously to reduce the size of a contour of the base, and to allow a selection for mounting the sensor mount rail between left and right. SOLUTION: A base 2 and a sensor mount rail 15 of a linear actuator 1 are respectively constructed with shape materials. The sensor mount rail 15 is engaged from the lengthwise direction of the base 2 with engaging parts for mounting the rail 14 on the both ends in crosswise direction of the base 2, and is clamped by end plates fixed to the both ends in the lengthwise direction of the base 2 to integrally assemble the sensor mount rail 15 and the base 2. This constitution reduces the distorsion and reduces the size of a contour of the base 2. Also, this constitution allows a selection for mounting the sensor mount rail 15 between left and right.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear actuator having a sensor mounting groove for mounting a sensor for detecting a moving position of a slide body reciprocating along a base by a driving device mounted along the base.

[0002]

2. Description of the Related Art Conventionally, a driving device mounted along a base reciprocates a slide guided along a longitudinal direction of a base, and a sensor mounting groove for mounting a sensor for detecting a moving position of the slide is formed. For example, Japanese Patent Application Laid-Open No. 2502856 and Japanese Patent Application Laid-Open No. HEI 9-177717 disclose such devices.
In these, a sensor mounting rail having a mounting groove is integrally formed on a side surface of the base. In addition, Japanese Unexamined Patent Publication
In the device disclosed in JP-A-9-227351, a sensor mounting rail for mounting a sensor is mounted on a side wall surface of a base from a width direction (a direction perpendicular to a longitudinal direction). Japanese Patent Laying-Open No. 3-28508 discloses a rodless cylinder which is a linear actuator without a base, and a longitudinal movement of a slide body provided integrally with a piston of the rodless cylinder. A sensor mounting rail provided with a mounting groove for a sensor for detecting a position is mounted on an outer peripheral surface of an end cap at both ends in a longitudinal direction of the rodless cylinder from a width direction.

[0003]

In the prior art, the sensor mounting rail and the base are integrally formed as a shape, and the shape of the shape is changed due to the difference in thickness between the sensor mounting rail and the base when the shape is formed. There is a problem that the portion where the sensor mounting rail is formed is distorted. In addition, since the sensor mounting rail and the base are integrated, the outer shape of the profile increases, which causes a problem that the profile of the profile increases. In addition, since the sensor mounting rail is formed integrally with the base, the sensor mounting rail is determined on both sides or one side in the base width direction from the beginning, and there is a problem that the position of the sensor mounting rail cannot be freely selected left and right.

Also, in the above, the sensor mounting rail and the base are separately formed, but in order to mount the sensor mounting rail on the side wall surface of the base from the width direction, a fixing for mounting the sensor mounting rail on the side wall surface of the base is performed. The screw hole of the screw must be machined from the width direction, and the screw hole for screwing the end plate to both ends in the longitudinal direction of the base must be machined from two directions. Since the length of the linear actuator is appropriately set, it is necessary to machine the screw holes at pitches in the base longitudinal direction of the screw holes corresponding to the respective base lengths.

[0005] Further, although the present invention differs from the present invention in that it does not have a base, a sensor mounting rail is screwed from the width direction to the side surface of the end cap, and a rodless cylinder having a plurality of lengths exists. Therefore, there is a problem that it is necessary to machine from two directions and to machine thread holes having a pitch corresponding to the length of each rodless cylinder. Further, when the apparatus is mounted on a mechanical device so that both ends are supported only by the end cap portion, the overall rigidity is lower than that using a base, and there is a possibility that the linear guide lacks smoothness.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent distortion occurring in a profile when a sensor mounting rail and a base are extruded or drawn and to reduce the size of the profile. It is another object of the present invention to select the mounting of the sensor mounting rail on the left and right in the width direction. Another object of the present invention is to simplify the processing by reducing the processing direction of the base and eliminating the processing corresponding to the screw hole pitch set for each length of each linear actuator.

[0007]

According to the present invention, there is provided a linear actuator which reciprocates a slide guided on a base along a longitudinal direction of the base by a driving device mounted along the base. So,
In a linear actuator having a sensor mounting groove for mounting a sensor for detecting a movement position of the slide body, a base for mounting a driving device, and a sensor mounting rail having a sensor mounting groove are each formed of a mold, and the base is The sensor mounting rail is integrally assembled (claim 1).

The sensor mounting rail corresponds to the length of the base, and the sensor mounting rail is sandwiched between end plates fixed to both longitudinal ends of the base. A fixing screw is screwed in from (claim 2).

Further, the sensor mounting rail is provided with a pilot hole for screwing a fixing screw over the entire length in the longitudinal direction.

[0010] The base is formed with symmetrical rail mounting engagement portions on both sides in the width direction, and the sensor mounting rail has an engaged portion complementary to the rail mounting engagement portion. The rail mounting engagement portion is engaged with the engaged portion (claim 4).

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The linear actuator 1 shown in FIGS. 1 to 4 includes a base 2, a rodless cylinder 3 as a driving device, a linear guide 4, and a slide body 5. The base 2 is made of, for example, an extruded member of an aluminum alloy, and has a U-shaped cross section as shown in FIG. 5 so that the rodless cylinder 3 is disposed on the inner wall surface 6a side. Has become. As shown in FIGS. 5 and 6, a T groove 9 for attaching an attachment holder 8 and a T groove 10 for attaching a guide rail 4a of two linear guides 4 on both sides in the width direction are formed on an upper wall surface 7a of the base 2. On both sides in the width direction of the wall surface 11a and the side wall surface 12a, T-grooves 13 for mounting the linear actuator 1 are respectively provided over the entire length in the longitudinal direction of the base 2. A nut 47 for fixing the linear actuator 1 to a mechanical device or the like is inserted into each T groove 13 before the end plates 25 and 26 are attached to both ends of the base 2.

Further, a T-shaped rail mounting engaging portion 14 is formed integrally on the both side surfaces 12a on both sides in the width direction in the longitudinal direction of the base 2 symmetrically in the left-right direction.
As shown in FIG. 5, both ends in the longitudinal direction are cut so as to be shorter than the entire length of the base 2. The cutting portions at both ends in the longitudinal direction are a fixing screw 16 for mounting a sensor mounting rail 15 described later and an end surface 14 a of the rail mounting engaging portion 14.
Is cut to a length that does not interfere with Base 2 has
A through hole 2 </ b> A having a convex cross section is formed through the bottom wall 11 over the entire length, and a bolt cut by a predetermined length from both ends in the longitudinal direction of the base 2 is formed in the upper wall 6 of the through hole 2 </ b> A. An insertion groove 19 is formed. On the lower surface of the upper wall 6 of the through-hole 2A, a projection 20 is integrally formed over the entire length of the through-hole 2A, and both longitudinal end portions thereof are cut out by a predetermined length, so that a cylinder nut 17 having a rectangular cross section has an inner end in the cylinder axial direction. And a restricting portion 20A that determines the axial position of the cylinder nut 17 in contact with the cylinder nut 17, and both ends of the through hole 2A are insertion holes 18 into which the cylinder nut 17 is inserted. Reference numeral 21 denotes an air passage 21 integrally formed over the entire length in the longitudinal direction.

[0013] As shown in FIG.
Reference numeral 5 denotes a shape member formed by extruding, for example, an aluminum alloy, similarly to the base 2, and has a length substantially similar to the entire length of the base 2. The sensor mounting rail 15 has a sensor mounting groove 22 and an engaged portion 23 formed over the entire length in the longitudinal direction. The engaged portion 23 is formed in a complementary shape capable of engaging with the rail attachment engaging portion 14, and a portion thereof is a screw-down hole 24 for the fixing screw 16 over the entire length in the longitudinal direction. The sensor mounting groove 22 includes a sensor mounting portion 22a for mounting a sensor and a lead wire holding portion 22b capable of holding a lead wire.

The sensor mounting rail 15 is configured such that the engaged portion 23 is engaged with both or one of the rail mounting engaging portions 14 on both sides in the width direction of the base 2 as necessary, and the longitudinal direction of the base 2 is changed. End plate 2 fixed to the end
In a state of being sandwiched between the base plates 5 and 26, the base plate 2 is fixed to the end plates 25 and 26 by fixing screws 16 screwed into the pilot holes 24 from the longitudinal direction of the base 2, and is integrally assembled to the base 2. As described above, since the base 2 and the sensor mounting rail 15 which are separately formed from the shape members are integrally assembled, the sensor mounting rail 15
In addition to preventing the distortion at the time of extrusion molding caused by the difference in thickness between the base 2 and the base 2, the outer shape of the base 2 can be reduced by using the sensor mounting rail 15 separately. The mold to be used can be reduced, and the cost is reduced. In addition, the mounting of the sensor mounting rail 15 to the base 2 can be selected in both or one of the width directions or without mounting as required. In addition, the sensor mounting rail 15 is integrally formed with the pilot hole 24 which is screwed in the longitudinal direction and the fixing screw 16 is screwed from the longitudinal direction of the base 2 and assembled to the base 2. Compared to the case of mounting, the processing from the base 2 width direction can be reduced,
This is suitable because processing corresponding to the screw hole pitch for each length in the longitudinal direction of each linear actuator 1 is not required.

One end plate 25 fixed to the longitudinal end of the base 2 is provided with supply / discharge ports 27, 28, and the other end plate 26 is provided with an air passage 29, and the air passage 29 is provided in the air passage 29. The end pipe 30 is slidably inserted, and the supply / discharge port 28 is connected to the air passage 2 of the base 2.
1 and communicates with the air passage 29. When the rodless cylinder 3 is provided on the base 2, two pressing screws 44 for pressing the end pipe 30 toward the rodless cylinder 3 are screwed on the end plate 26 on the left and right sides of the end pipe 30. Have been combined.

As shown in FIGS. 1 to 3, a rodless cylinder 3 is disposed on the inner surface 6 of the base 2 to which the end plates 25 and 26 are fixed. The rodless cylinder 3 is a known one disclosed, for example, in JP-A-10-299714. A cylinder tube 32 provided with a cylinder hole 31 is provided with a slit 33 over the entire length in the longitudinal direction.
An end cap 34 that fits into and blocks the end cap is fixed. Both ends of the inside and outside seal bands 35 and 36 for closing the inside and outside of the slit 33 are fixed to the end cap 34. The end caps 34 at both ends are provided with air passages 37 in the cylinder longitudinal direction. A piston 38 slidable in the longitudinal direction is provided in the cylinder hole 31.
And a part of the piston 38 protrudes outward from the slit 33 to integrally form a mount 39, and a mount cover 40 is fitted to the mount 39 to constitute an external moving body.

The attachment of the rodless cylinder 3 to the base 2 is performed by the left end cap 34 shown in FIGS.
And the supply / discharge port 27 of the left end plate 25 and the air passage 37 of the right end cap 34 and the end pipe 30 in the right end plate 26 communicate with each other. The mounting nut 41 inserted through the insertion groove 19 into the cylinder nut 17 in the insertion hole 18 is inserted through the insertion groove 19 from the direction orthogonal to the base 2.
It is screwed and fixed. The end pipe 30 is pressed against the end cap 34 on the end plate 26 side of the rodless cylinder 3 disposed on the base 2 by tightening the pressing screw 44 from the longitudinal direction of the base 2, and the air passage 37 of the end cap 34 at both ends is pressed. Are connected to the supply / discharge port 27 and the end pipe 30 respectively. A slide body 5 is integrally attached to an external moving body of the rodless cylinder 3.
A guide rail 4a of the linear guide 4 is fixed to the T groove 10 of the base 2, and a guide 4b of the linear guide 4 slidably guided on the guide rail 4a is a slide body 5.
It is provided at the lower part. A sensor magnet 42 is provided on the lower surface of the slide body 5. T-slot 9 of base 2
Attachment holders 8 having shock absorbers 43 are fixed opposite to each other at both ends in the longitudinal direction. still,
In the present invention, the molded product is formed by extruding the sensor mounting rail 15 but is not limited to the molded product.

In the linear actuator 1 configured as described above, the slide body 5 reciprocates in the longitudinal direction together with the piston 38 by the supply and discharge of compressed air (pressure fluid) from the supply and discharge ports 27 and 28, and the sensor mounting rail. The position of the slide body is detected by detecting the sensor magnet 43 by the sensor attached at any position of No. 15.

[0019]

As described above, according to the present invention, since the sensor mounting rail and the base are each formed of a shape member, distortion of the sensor mounting rail and the base is reduced. Further, by separating the sensor mounting rail from the base, the outer shell of the base can be reduced, and the shape of the shape member can be reduced, and the cost can be reduced. In addition, the right and left mounting in the width direction of the sensor mounting rail can be selected. In addition, since the sensor mounting rail is screwed in from the longitudinal direction of the base with a fixing screw and fixed, it is not necessary to perform processing in the base width direction as in the past, and processing corresponding to the longitudinal pitch of the screw holes for each base. This is preferable because it is not necessary to carry out.

[Brief description of the drawings]

FIG. 1 is a front view of a linear actuator.

FIG. 2 is a II view of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is an IV view of FIG. 1;

FIG. 5 is a side view of a base.

FIG. 6 is a VI view of FIG. 5;

FIG. 7 is a side view of a sensor mounting rail.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Linear actuator 2 Base 3 Drive device 5 Slide body 14 Rail attachment engagement part 15 Sensor attachment rail 16 Fixing screw 22 Sensor attachment groove 23 Engaged part 24 Screw-in pilot hole 25, 26 End plate

Claims (4)

[Claims] 1. A linear actuator for reciprocating a slide guided on a base along the length of the base by a driving device mounted along the base, and a sensor for detecting a movement position of the slide is mounted. In a linear actuator having a sensor mounting groove, a linear actuator in which a base for mounting a drive device and a sensor mounting rail having a sensor mounting groove are each formed of a mold material, and the sensor mounting rail is integrally assembled to the base. . 2. The sensor mounting rail has a length corresponding to the length of the base. The sensor mounting rail is sandwiched between end plates fixed to both longitudinal ends of the base. 2. The linear actuator according to claim 1, wherein a fixing screw is screwed in from a direction. 3. The linear actuator according to claim 2, wherein the sensor mounting rail is formed with a pilot hole for screwing a fixing screw over the entire length in the longitudinal direction. 4. A rail mounting engaging portion is formed symmetrically on both sides in the width direction on the base, and the sensor mounting rail is
4. An engaging portion having a complementary shape with the rail mounting engaging portion, wherein the rail mounting engaging portion and the engaged portion are engaged with each other. The linear actuator according to the item.