JPH047370Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a rotary actuator, particularly a rotary actuator that obtains an oscillating torque on a shaft body through a pinion meshed with a rack that is reciprocated by fluid pressure. Regarding Eta.

[Background Art] Generally, as an actuator for position control of machine tools and various automatic devices, there is a so-called rotary actuator that extracts fluid pressure energy such as compressed air as a swing torquer such as a shaft.

On the other hand, in fields that require extremely high levels of cleanliness in the work space, such as the medical field and semiconductor manufacturing field, it is common practice to remove dust, etc. floating inside, in order to maintain extremely high cleanliness in the work space. A so-called clean room is constructed in which the amount is reduced to a predetermined amount or less, and the required work is performed within the clean room.

For this reason, consideration must be given to the fluid pressure operated equipment used in the clean room, such as rotary actuators, so that the cleanliness of the clean room is not obstructed by dust generation, etc. In a rotary actuator having such a structure, it is inevitable that the working space is contaminated due to dust generation from sliding parts or leakage of compressed air for driving.

[Object of the invention] An object of the invention is to provide a rotary actuator that can prevent contamination of a working space by dust and working fluid.

[Summary of the invention] The rotary actuator of the invention includes a cylinder bored inside the main body, a cylinder cover that closes one end of the cylinder, a rack housed inside the cylinder, and a rack supported inside the main body. , a pinion that meshes with the rack, a piston that contacts one end of the rack inside the cylinder and forms a fluid chamber between it and the cylinder cover, and a piston that is bored in the cylinder cover to supply and discharge working fluid to and from the fluid chamber. a dust-proof cover that seals the space where the rack and pinion are located on the back side of the piston; a dust-collection port that is bored in this dust-proof cover and communicates with the space; and a sealing member that seals the support portion.

[Function] According to the rotary actuator of the present invention described above, the space inside the main body on the back side of the piston where the rack, pinion, etc. are located is sealed by the dust cover and the sealing member disposed at the pinion support. As a result, it is airtightly isolated from the outside, and dust generated in the space and working fluid leaking into the space from the pinion side can be captured via the dust collection port and reliably discharged to the desired piping system, etc. .
This prevents the working fluid and dust generated during operation from scattering into the working space, thereby reliably preventing contamination of the working space.

[Example] FIG. 1 is a cross-sectional view of a rotary actuator that is an example of the present invention, and FIG.
FIG. 2 is a sectional view of a portion indicated by a line in the figure.

Inside the body 1 of the rotary actuator in this embodiment, a cylinder 2 and a cylinder 3 having parallel axes in the same plane are formed, and a cylinder 2 and a cylinder 3 are formed perpendicularly to the plane through the boundary between the cylinders 2 and 3. A pinion 4 and a main shaft 5 coaxially and integrally formed with the pinion 4 are provided.

One end of the main shaft 5 is projected to the outside of the main body 1,
Further, the main shaft 5 is rotatably supported by a bearing metal 6 and a bearing metal 7 fitted to the main body 1 at a position where a pinion 4 integrally formed with the main shaft 5 is sandwiched therebetween.

The bearing metals 6 and 7 are configured to be held in the main body 1 by a bearing presser 8 and a bearing presser 9, respectively, which are fitted into the main body 1.

In addition, the outer periphery of the bearing metals 6 and 7 and the main body 1
An O-ring 10 and an O-ring 11 are respectively installed between the bearing holders 8 and 9, and an O-ring 12 is installed between the inner periphery of the bearing holders 8 and 9 and the outer periphery of the main shaft 5.
and O-rings 13 are installed, respectively.
The penetrating portion of the main shaft 5 in the main body 1 is sealed so that the working fluid does not leak, and the structure is such that dust generated inside the main body 1 is prevented from being scattered to the outside.

The teeth of the pinion 4 are exposed inside the cylinders 2 and 3, and are carved with linearly arranged teeth on the side surface of a cylindrical member slidably housed in the axial direction of the cylinders 2 and 3. The racks 14 and 15 are meshed with each other.

A piston portion 16 and a piston portion 17 are formed at one end of the racks 14 and 15, and a fluid chamber A and a fluid chamber B are formed between the piston portions 16 and 17 and a cylinder cover 18 that closes one end of the cylinders 2 and 3. are each configured.

Then, by alternately applying fluid pressure such as compressed air through a pressure port 19 and a pressure port 20 formed through the cylinder cover 18 and communicating with the fluid chambers A and B, respectively, the racks 14 and 15 are The structure is such that a predetermined rocking torque is generated on the main shaft 5 via a pinion 4 meshed with racks 14 and 15 by reciprocating in opposite directions.

An O-ring 21 and an O-ring 22 are attached to the parts where the cylinder cover 18 and the cylinders 2 and 3 are in close contact, respectively. This prevents dust and the like from being scattered to the outside of the main body 1.

On the outer periphery of the piston parts 16 and 17, a piston part packing 23 and a piston part packing 2 are provided.
4 is provided, and the sliding portions between the piston portions 16 and 17 and the cylinders 2 and 3 are configured to be kept airtight.

Further, a dustproof cover 26 is airtightly attached to the other ends of the cylinders 2 and 3 formed in the main body 1 via a packing 25, and a piston part 16 formed at the ends of the racks 14 and 15, respectively
The space on the back side of 1 and 17 is sealed.

In this case, a dust collection port 27 is provided through the center of the dustproof cover 26 and communicates with both the spaces on the back side of the piston parts 16 and 17.

By connecting this dust collection port 27 to, for example, a predetermined vacuum system or piping such as a relief port (not shown), the inner circumferential surfaces of the cylinders 2 and 3 and the piston portion 1 are connected to each other inside the main body 1.
6 and 17, and pinion 4 and rack 1.
Dust such as fine metal powder generated from the meshing portions with the piston parts 4 and 15 flows into the fluid chambers A and B, and passes through the piston part gaskets 23 and 24 attached to the pinion parts 16 and 17. Compressed air leaking to the rear side of the main body 1 can be captured, and dust generated inside the main body 1 and foreign matter in the working fluid such as compressed air can be prevented from being scattered to the outside of the main body 1. It is something that

The operation of this embodiment will be explained below.

First, the main body 1 of the rotary actuator is mounted on a predetermined mounting device (not shown) inside a clean room (not shown), for example.

The pressure ports 19 and 20 are connected to a predetermined fluid pressure source (not shown) via a predetermined control valve mechanism (not shown), and the dust collection port 27 is
For example, it is connected to a predetermined vacuum system or piping (not shown) such as a relief port.

Next, fluid pressure such as compressed air is alternately applied to the fluid chambers A and B of the cylinders 2 and 3 through the pressure ports 19 and 20 by the control valve mechanism, and the racks 14 and 15 reciprocate in opposite directions. A predetermined swing torque is generated on the main shaft 5 via the pinion 4 which is engaged with the racks 14 and 15, and a predetermined work is performed.

In this case, inside the main body 1, the sliding parts between the piston parts 16 and 17 and the cylinders 2 and 3, as well as the sliding parts between the pinion 4 and the racks 14 and 15.
Although it is inevitable that dust such as metal powder is generated from the meshing part with the main body 1, in this embodiment, a dust collection port 27 communicating with the inside of the sealed main body 1 is provided. Dust and piston gaskets 23 and 24 generated inside the
Since the structure is such that compressed air leaking to the rear side of the piston parts 16 and 17 through the peripheral part of the main body 1 is captured, dust generated inside the main body 1 and leaked compressed air are collected into the dust collection port 27. By guiding the air to a predetermined vacuum system or piping such as a relief port to be connected, dust generated inside the main body 1 and leaked compressed air can be prevented from being scattered outside the main body 1. The work space in which the rotary actuator is used can be prevented from being contaminated by dust generated from the rotary actuator, leaked compressed air, and the like.

It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, the fluid for operating the rotary actuator is not limited to compressed air, but may be pressurized oil or the like.

[Effects] (1) A cylinder bored inside the main body, a cylinder cover that closes one end of the cylinder, a rack housed inside the cylinder, a pinion supported inside the main body and meshed with the rack, A pinion that contacts one end of the rack inside the cylinder and forms a fluid chamber between it and the cylinder cover, a pressure port that is bored in the cylinder cover and supplies and discharges working fluid to and from the fluid chamber, and the back of the pinion. A dust cover that seals the space where the side rack and pinion are located, a dust collection port that is drilled in the dust cover and communicates with the space, and a seal that is attached to the support for the pinion body and seals the support. Because of the structure, the space inside the main body on the back side of the pinion where the rack, pinion, etc. are located is protected from the outside by the dust cover and the sealing member placed on the pinion support. It is airtightly shut off, and dust generated in the space and working fluid leaking into the space from the piston side can be reliably captured through the dust collection port and reliably discharged to a desired piping system.

This prevents the working fluid and dust generated during operation from scattering into the working space, and provides the effect that contamination of the working space in which the rotary actuator is installed can be reliably prevented.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a rotary actuator that is an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the portion indicated by the line - in FIG. 1... Body, 2, 3... Cylinder, 4... Pinion, 5... Main shaft, 6, 7... Bearing metal, 8,
9... Bearing holder, 10, 11, 12, 13...
O-ring (sealing member), 14, 15...Rack,
16, 17... Piston part, 18... Cylinder cover, 19, 20... Pressure port, 21, 22...
...O-ring, 23, 24... Piston part packing, 25... Packing, 26... Dust-proof cover, 2
7...Dust collection port.

Claims (1)

[Scope of utility model registration request] A cylinder bored in the main body, a cylinder cover that closes one end of the cylinder, a rack housed in the cylinder, a pinion supported in the main body and meshed with the rack, and a cylinder cover that closes one end of the cylinder. a piston that abuts one end of the rack inside and defines a fluid chamber between it and the cylinder cover; and a piston that is bored in the cylinder cover;
A pressure port through which working fluid is supplied to and discharged from the fluid chamber; a dustproof cover that seals a space on the back side of the piston where the rack and pinion are located; and a dustproof cover that is bored through the dustproof cover and communicates with the space. A rotary actuator comprising: a dust collection port; and a sealing member attached to a support portion of the pinion for sealing the support portion.