JP5094809B2 - Linear actuator - Google Patents

Description

  The present invention relates to a linear actuator that has a rod that is movable in the axial direction by a linear drive mechanism and that linearly moves a member attached to the tip of the rod.

  Conventionally, as a linear actuator, a housing containing a linear drive mechanism, an outer cylinder coupled to the housing, a rod disposed in the outer cylinder and movable in the axial direction by the linear drive mechanism, and an end of the outer cylinder One having a rod guide arranged and slidably supporting the rod is known.

  As shown in FIGS. 5 and 6, in the known linear actuator 500, the rod 530 is disposed in an outer cylinder 520 having a rectangular outer shape, and slides on a rod guide 540 disposed at an end of the outer cylinder 520. It is supported and configured to be movable back and forth in the axial direction by rotation of a screw shaft 551 of a linear drive mechanism (not shown).

  The rod guide 540 has an insertion portion 545 inserted into the inner peripheral surface of the end portion of the outer cylinder 520, and a flange portion 544 having the same rectangular shape as the outer cylinder 520 and provided with mounting holes 542 in the vicinity of the four corners. In addition, an oil-impregnated metal 541 that slides with the rod 530 and a seal 546 member are provided on the inner peripheral surface.

  The rod guide 540 is fixed to the outer cylinder 520 by screwing the mounting bolt 543 through the mounting hole 542 of the flange portion 544 into the screw hole 521 on the end surface of the outer cylinder 520, and the rod 530 is axially fixed. Only slidably supported (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2005-36899 (Page 4, FIGS. 17 and 18)

  However, in this known linear actuator 500, the oil-impregnated metal 541 that slides with the rod 530 needs to be fixed to the inner peripheral surface of the rod guide 540 as a separate member.

  Further, since the rod guide 540 is fixed to the outer cylinder 520 by passing the mounting bolt 543 through the mounting hole 542 of the flange portion 544 and screwing into the screw hole 521 on the end surface of the outer cylinder 520, assembly and maintenance can be performed. In addition, the number of man-hours for attachment and removal increases, and members other than the rod guide 540 cannot be attached to the end surface of the outer cylinder 520, and there is a problem that the installation place and method of the linear actuator 500 are limited. It was.

  The present invention solves the problems of the prior art as described above, i.e., the object of the present invention is to slide the rod smoothly and accurately in a simple configuration, reduce the cost of parts, It is another object of the present invention to provide a linear actuator that facilitates assembly and maintenance and can be used in various forms of applications.

  The invention according to claim 1 includes a housing containing a linear drive mechanism, an outer cylinder coupled to the housing, a rod disposed in the outer cylinder and movable in the axial direction by the linear drive mechanism, In a linear actuator having a rod guide disposed at an end of an outer cylinder and slidably supporting the rod, the rod guide is made of a single material having a sliding surface that slides directly on the rod. The single material is resin, and the rod guide has an insertion portion having a male screw portion screwed into the inner peripheral surface of the end portion of the outer cylinder, and an outer shape larger than the inner peripheral surface. And a flange portion that protrudes from the end portion and is engaged with the end surface of the outer cylinder, the outer cylinder has a screw hole in the end surface on the rod guide side, and the flange portion It is formed in an outer shape that does not cover the screw hole on the end face of the tube. The Rukoto is intended to solve the above problems.

  In the invention according to claim 2, in addition to the configuration of the linear actuator according to claim 1, the flange portion is formed in a cylindrical shape surrounding the rod, and the outer cylinder has a rectangular outer shape. By forming the screw holes in the vicinity of the four corners of the end face, the problem is further solved.

  In the invention according to claim 3, in addition to the configuration of the linear actuator according to claim 1 or 2, a tip attachment portion is attached to the tip of the rod, and the rod guide On the distal end side of the sliding surface, a seal member accommodation groove for accommodating a sealing member is provided continuously to the sliding surface at a position closer to the distal end mounting portion than the end surface of the outer cylinder in the axial direction. Thus, the above-described problem is further solved.

  A linear actuator according to a first aspect of the present invention includes a housing containing a linear drive mechanism, an outer cylinder connected to the housing, and a rod disposed in the outer cylinder and movable in the axial direction by the linear drive mechanism. And a linear actuator having a rod guide disposed at the end of the outer cylinder and slidably supporting the rod, the rod guide is made of a single material having a sliding surface that slides directly on the rod. One material is resin, and the rod guide has an insertion part having a male screw part screwed into the inner peripheral surface of the end part of the outer cylinder, and has an outer shape larger than the inner peripheral surface and protrudes from the end part. A flange portion that is locked at the end surface of the outer cylinder, the outer cylinder has a screw hole on the end surface on the rod guide side, and the flange portion is formed in an outer shape that does not cover the screw hole on the end surface of the outer cylinder. Therefore, the rod can be smoothly and accurately slid linearly with a simple configuration. Is to be able, it is possible to reduce the component cost.

  In addition, the rod guide has an insertion portion having a male thread portion that is screwed onto the inner peripheral surface of the end portion of the outer cylinder, and has an outer shape larger than the inner peripheral surface of the outer cylinder and protrudes from the end portion of the outer cylinder and engages with the end surface. By having the flange portion to be stopped, assembly and maintenance can be facilitated with a simple configuration.

  Further, since the rod guide is made of resin, assembly and maintenance can be facilitated with a simpler configuration.

  Furthermore, the outer cylinder has a screw hole on the end face on the rod guide side, and the flange portion is formed in an outer shape that does not cover the screw hole on the end face of the outer cylinder. Members other than the rod guide can be attached, and can be used in various forms of applications.

  In addition to the effect of the linear actuator according to claim 1, the linear actuator according to the second aspect of the invention has a flange portion formed in a cylindrical shape surrounding the rod, and the outer cylinder has a rectangular outer shape. By being formed and having screw holes in the vicinity of the four corners of the end face, screw holes that are not covered by the cylindrical flange portion can be provided in the vicinity of the four corners of the end face of the outer cylinder.

  In addition to the effect of the linear actuator according to claim 1 or 2, the linear actuator of the invention according to claim 3 has a tip mounting portion attached to the tip of the rod, and the rod guide On the tip side of the sliding surface, a seal member receiving groove for receiving the seal member is provided continuously in the axial direction at a position closer to the tip mounting portion than the end surface of the outer cylinder. Thus, the sliding surface can be continued to the seal member accommodation groove.

The perspective view of the linear actuator which is one Example of this invention. The partial cross section side view of the linear actuator which is one Example of this invention. FIG. 3 is a partially enlarged view of FIG. 2. The front view of the linear actuator which is one Example of this invention. The partial enlarged view of the conventional linear actuator. The front view of the conventional linear actuator.

  A linear actuator according to the present invention includes a housing containing a linear drive mechanism, an outer cylinder coupled to the housing, a rod disposed in the outer cylinder and movable in the axial direction by the linear drive mechanism, and an outer cylinder In a linear actuator having a rod guide disposed at an end and slidably supporting a rod, the rod guide is made of a single material having a sliding surface that slides directly on the rod, and the single material is An insertion portion having a male screw portion screwed to the inner peripheral surface of the end portion of the outer cylinder, and a rod guide having an outer shape larger than the inner peripheral surface and projecting from the end portion; The outer cylinder has a screw hole on the end surface on the rod guide side, and the flange part is formed in an outer shape that does not cover the screw hole on the end surface of the outer cylinder. With a simple configuration, the rod can slide smoothly and accurately in a straight line. As long as it can reduce the cost of parts, facilitate assembly and maintenance, and can be used in various forms of applications, the specific embodiment is not limited. No matter what.

Below, the Example of the linear actuator of this invention is described based on drawing.
As shown in FIGS. 1 to 4, in the linear actuator 100 according to the embodiment of the present invention, the rod 130 is disposed in the outer cylinder 120 having a rectangular outer shape, and is disposed at the end of the outer cylinder 120. It is configured to be movable back and forth in the axial direction by rotation of a screw shaft 151 of a linear drive mechanism (not shown) that is slidably supported by the rod guide 140 and included in the housing 110.
A tip attachment portion 131 is attached to the tip portion of the rod 130. The screw shaft 151 is rotationally driven by the motor 101.

  The rod guide 140 is made of a single material, has an insertion portion 145 to be inserted into the inner peripheral surface of the end portion of the outer cylinder 120, and has an outer shape larger than the inner peripheral surface of the outer cylinder 120 and protrudes from the end portion of the outer cylinder 120. And a flange portion 144 that is locked by the end surface 122.

  A male thread portion is formed on the outer peripheral surface of the insertion portion 145 of the rod guide 140 and is fixed to the outer tube 120 by screwing with the inner peripheral surface of the outer tube 120, and on the inner peripheral surface of the rod guide 140. A sliding surface 141 that directly contacts the rod 130 is formed, and supports the rod 130 so as to be slidable only in the axial direction.

Further, a seal member 146 is provided on the distal end side of the sliding surface 141 on the inner peripheral surface of the rod guide 140. The seal member housing groove 147 that houses the seal member 146 is continuously formed on the distal end side of the sliding surface 141 at a position closer to the distal end mounting portion 131 than the end surface 122 of the outer cylinder 120 in the axial direction. Is provided.
Further, the flange portion 144 of the rod guide 140 is formed in a cylindrical shape so as to surround the rod 130, and is formed in a shape that does not cover the screw holes 121 provided in the vicinity of the four corners of the end surface 122 of the rectangular outer cylinder 120. Has been.

  Since the rod guide 140 is made of a single material, the rod 130 can be smoothly and accurately linearly slid with a simple configuration, and the component cost can be reduced.

The rod guide 140 may be formed of any material, and if it is formed of a resin material having self-lubricating properties, the rod guide 140 can be easily manufactured and can impart a vibration damping effect and a heat insulating effect.
Moreover, it is good also as a metal material which has an oil-impregnated surface in a sliding part.

  Further, since the rod guide 140 is directly screwed and fixed to the inner peripheral surface of the outer cylinder 120, assembly and maintenance can be facilitated.

  The flange 144 of the rod guide 140 has a shape that does not cover the screw holes 121 provided in the vicinity of the four corners of the end surface 122 of the outer cylinder 120, so that the screw holes 121 can be used according to the application and environment to be used. Thus, various members other than the rod guide 140 can be attached to the outer cylinder 120, and can be used in various forms of applications.

  As described above, according to the linear actuator of the present invention, the rod can be smoothly and accurately linearly slid with a simple configuration, the parts cost can be reduced, and assembly and maintenance are facilitated. At the same time, it can be used in various forms of applications, and its effects are enormous.

100, 500 ... linear actuators 110, 510 ... housings 120, 520 ... outer cylinders 121, 521 ... screw holes 130, 530 ... rods 131, 531 ... tip mounting parts 140, 540 ... Rod guide 541 ... Oil-impregnated metal 542 ... Mounting hole 543 ... Mounting bolts 144 and 544 ... Flange parts 145 and 545 ... Insertion parts 146 and 546 ... Seal members 151, 551 ... Screw shaft

Claims (3)

A housing enclosing a linear drive mechanism; an outer cylinder connected to the housing; a rod disposed in the outer cylinder and movable in the axial direction by the linear drive mechanism; and disposed at an end of the outer cylinder. In a linear actuator having a rod guide that slidably supports a rod,
The rod guide is made of a single material having a sliding surface that slides directly with the rod;
The single material is a resin;
The rod guide has an insertion portion having a male screw portion that is screwed into an inner peripheral surface of an end portion of the outer cylinder, and has an outer shape larger than the inner peripheral surface and protrudes from the end portion to end face of the outer cylinder And a flange portion to be locked with,
The outer cylinder has a screw hole in the end face on the rod guide side,
The linear actuator according to claim 1, wherein the flange portion is formed in an outer shape that does not cover a screw hole in the end surface of the outer cylinder. The flange portion is formed in a cylindrical shape surrounding the rod,
2. The linear actuator according to claim 1, wherein the outer cylinder has a rectangular outer shape and has the screw holes in the vicinity of four corners of the end face. A tip mounting portion is attached to the tip of the rod,
A seal member receiving groove for receiving a seal member is provided in the sliding surface at a position closer to the tip mounting portion than the end surface of the outer cylinder in the axial direction on the tip side of the sliding surface of the rod guide. The linear actuator according to claim 1 or 2, wherein the linear actuator is provided continuously.

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