WO2014092255A1

WO2014092255A1 - Servo cylinder

Info

Publication number: WO2014092255A1
Application number: PCT/KR2013/003293
Authority: WO
Inventors: 진문영; 조충래; 조동현; 홍민석
Original assignee: 삼익정공 주식회사
Priority date: 2012-12-14
Filing date: 2013-04-22
Publication date: 2014-06-19
Also published as: KR101428536B1; KR20140077562A; CN105051424A; CN105051424B

Abstract

The present invention relates to a servo cylinder which converts a rotational motion of a motor into a linear motion of a piston rod by using a TM screw or a ball screw and combines a linear busing to the piston rod inside a housing so as to enable an infinite linear motion, wherein the housing and the rod are made from high-rigidity bearing steel. In addition, a ball retainer is provided for guiding a row of balls capable of infinite linear motion inside the housing, an anti-rotation guide is applied for controlling the angle of torsion to enable obtainment of high durability, high-speed travel is enabled, and the linear busing is capable of maintaining a predetermined precision.

Description

[Revision 29.05.2013 under Rule 26] Servo Cylinder

The present invention is configured so that the rotational motion of the motor is converted to the linear motion of the piston rod by using a TM screw or ball screw nut, and a combination of the linear bushing to allow the endless linear movement of the rod inside the housing, the housing and the rod The ball retainer is composed of high-strength bearing steel, guides the ball row to allow infinite linear movement inside the housing, and maintains a certain degree by applying the anti-rotation guide to control the rotation angle against torsion. The present invention relates to a servo cylinder using a linear bushing capable of high durability and high speed driving.

In general, the servo cylinder is an electric actuator to be applied as a substitute for pneumatic cylinder, and it is a cylinder for position control that can be applied to logistics systems of automobile assembly lines and mixed production systems of industrial automation, such as actuators for transfer systems and clamping devices. In addition, you need a low-end product.

Currently, the technology of servo cylinder is a type that converts the rotational motion of the motor into the linear motion of the piston rod. TM screw (screw) and ball screw nut (screw) are used, and in the general type, it is sliding with a guide for linear motion. Type is applied, and in case of high precision type, there are products with ball spline and needle guide.

Conventional servo cylinders generally use abrasion resistant Du Bush or abrasion resistant resin in the aluminum housing in order to convert rotational motion into linear motion, but they lack rigidity against external forces, speed and Due to the limitations of the stroke and sliding type, it is difficult to maintain accuracy.

Korean Patent Laid-Open Publication No. 1995-0011049 discloses a technical configuration of accurately positioning a piston of a servo cylinder at a target position using an electric motor and a ball screw, but employing a linear bushing improves the durability and accuracy of the servo cylinder. It is not related to improving the driving speed.

The problem to be solved by the present invention is to use a technical configuration that converts the rotational motion of the motor into the linear motion of the piston rod, by applying a combination of linear bushings capable of infinite linear motion as a guide for linear motion rolling motion with minimal frictional resistance It is possible to move lightly, and because of the rolling motion type to increase the rigidity of the external force of the rod, to provide high-speed driving, and to improve the durability of the servo cylinder.

Another problem to be solved by the present invention is to use a combination of linear bushing capable of infinite linear movement of the guide for linear motion using a technical configuration that converts the rotational motion of the motor into a linear motion of the piston rod, the housing and the rod The present invention provides a servo cylinder using a linear bushing configured of a rigid bearing steel and applying a rotation preventing guide capable of controlling an angle to a torsion, thereby maintaining a predetermined degree and controlling a torsion.

In order to solve the above problems, the technical solution of the present invention applies a form in which the rotational motion of the motor is changed to the linear motion of the piston rod, and the linear motion bearing is applied by combining a linear bushing capable of infinite linear motion. It is able to move lightly by rolling movement with frictional resistance, and obtains high rigidity by using bearing steel which is strong in the outer cylinder of the linear bushing, and has a ball retainer for guiding the ball heat inside the outer cylinder, and controls the angle for torsion The anti-rotation guide is applied, and the linear motion type is a rolling motion type, so it is possible to drive at high speed, and to implement a servo cylinder using a linear bushing to obtain accuracy, durability and sufficient rigidity.

Another technical solution of the present invention is to install the anti-rotation guide on one side of the piston rod adjacent to the ball screw to prevent the rotation of the piston rod in linear reciprocating movement, the left edge of the piston rod in the housing reciprocating piston rod The dust seal is installed to prevent dust from entering the outside, and to provide a smooth sliding of the piston rod, it provides a servo cylinder using a linear bushing with a die bush installed between the dust seal and the linear bushing.

Another technical solution of the present invention is to form a 4-6 trillion polygonal structure inside the servo cylinder outer cylinder to prevent rotation, and to produce a rotation prevention guide according to the shape of the 4-6 trillion polygonal structure formed inside the outer cylinder cylinder. The present invention provides a servo cylinder using a linear bushing fixed to one side of a piston rod adjacent to a ball screw.

The present invention utilizes a technical configuration for converting the rotational motion of the motor into a linear motion of the piston rod, by applying a combination of linear bushings capable of infinite linear motion as a guide for linear motion to make the rolling motion with minimum frictional resistance It is movable, and because of the rolling motion type, it is possible to drive at high speed, and there is an advantageous effect of improving durability.

Another effect of the present invention is to apply a combination of linear bushing capable of linear motion of the guide for linear motion using a technical configuration that changes the rotational motion of the motor into a linear motion of the piston rod, the housing and the piston rod high rigidity Consists of a bearing steel, and by applying a rotation preventing guide to control the angle to the torsion to maintain a predetermined degree and torsion.

1 shows a servo cylinder using a linear bushing according to the present invention (with a piston rod).

Figure 2 shows a servo cylinder using a linear bushing according to the present invention (the piston rod comes out).

Figure 3 illustrates one embodiment of a linear bushing designed and employed in the present invention.

The best form for the practice of the present invention is to apply the form to change the rotational motion of the motor to the linear motion of the piston rod in order to solve the above problems, the linear motion bearing is applied by combining a linear bushing capable of infinite linear motion It can move lightly by rolling motion with minimum frictional resistance. It gains high rigidity by using bearing steel which has strong outer cylinder of linear bushing, and has a ball retainer for guiding ball heat inside the outer cylinder. The anti-rotation guide is applied to control the rotation, and since the linear motion type is the rolling motion type, it is possible to drive at high speed, and to implement the servo cylinder using the linear bushing to obtain the accuracy, durability and sufficient rigidity.

The present invention uses a linear bushing capable of linear motion in the form of a linear motion of the piston rod in the form of converting the rotational motion of the motor to the piston rod as the main technical configuration to maintain a certain degree of rolling motion to maintain the friction It is a servo cylinder that can minimize the light and straight reciprocating movement.

The servo cylinder using the linear bushing according to the present invention can obtain high rigidity and durability by using a bearing steel with a rigid outer cylinder of the linear bushing, and is a rolling motion type in which a ball retainer for guiding ball rows is inserted into the outer cylinder. Therefore, high-speed driving (1000 mm / sec or less) is possible, there is an effect that can maintain a higher degree and longer durability than the sliding type servo cylinder.

A specific embodiment of the present invention will be described based on the drawings. 1 shows a servo cylinder using a linear bushing according to the present invention.

The present invention uses a linear bushing capable of infinitely linear movement of the linear motion guide in the form of converting the rotational motion of the motor into a linear motion of the piston rod, and the linear reciprocation motion of the piston rod is achieved by the rolling motion of the ball. It can be configured to make the friction resistance can be minimized, so it can lightly reciprocate linearly.

In the case of the conventional sliding type servo cylinder, in order to convert the rotational motion into the linear motion, a DU bush is generally used inside the aluminum housing, and a high wear resistance resin is used to control the twisting. There is a lack of rigidity against external forces, and it is difficult to maintain accuracy due to speed and stroke limitations and sliding types.

Looking at the technical configuration of the present invention based on FIG.

Since the electric energy is supplied to the motor 22 of FIG. 1, the shaft of the motor 22 rotates, and the rotating shaft of the motor 22 and the screw shaft 18 of FIG. 1 are fastened by a coupling to the screw shaft 18. The motor 22 rotates clockwise or counterclockwise.

A female screw is formed inside the ball screw nut (20 in FIG. 1) and is fastened to a male screw formed outside the screw shaft 18.

Ball screw nut (20 in Fig. 1) inserts a steel ball (ball) between the male threaded screw shaft and the female threaded ball screw nut to minimize frictional resistance and allow high-speed movement, high accuracy, and excellent durability. have.

In FIG. 1, the screw shaft 18 connected to the rotating shaft of the motor 22 is rotated by the rotation of the motor 22, and the ball screw nut fastened to the screw shaft 18 by the rotation of the screw shaft 18. 20 is a linear reciprocating motion along the screw shaft (18).

The principle of movement of the ball screw nut 20 is the same as that of the nut performing a linear reciprocating motion along the screw axis when the nut is rotated clockwise or counterclockwise by fastening the nut to the long screw shaft 18 on which the male screw is formed.

In Fig. 1, the piston rod (11 in Fig. 1) is linearly reciprocated when the ball screw nut 20 and the piston rod (11 in Fig. 1) are fixedly engaged so that the motor 22 rotates clockwise or counterclockwise. It is configured to

The piston rod 11 for the linear reciprocating motion is configured to allow a smooth reciprocating motion while maintaining a predetermined degree in the ball rolling motion of the linear bushing (16 in Fig. 1).

The ball retainer (17 in FIG. 1) for accommodating the ball (15 in FIG. 1) is inserted and fastened to the inside (outer cylinder) of the left side (on the drawing) of the servo cylinder employing the linear bushing.

That is, the left side of the servo cylinder is comprised by the linear bushing 16.

The present invention, after inserting the ball into the ball retainer (17) for accommodating the ball, when the piston rod is inserted and fastened so that the outer portion of the piston rod 11 can be smoothly reciprocated by the rolling motion of the ball Consists of.

Outside the ball retainer 17, a linear bushing is provided in a housing for guiding the piston rod 11 in a linear reciprocating motion.

Figure 3 shows one embodiment of a linear bushing, such a structure being employed in the housing of a servo cylinder according to the invention.

In the specification of the present invention, different reference numerals are assigned to the same components in the case of different drawings.

The housing in the linear bushing 16 is called the outer cylinder (33 in Fig. 3), it can be composed of a bearing steel excellent in strength and durability to withstand the rolling motion of the ball long.

In consideration of durability, the outer cylinder may be manufactured in a structure in which only a portion of the ball that performs rolling motion is formed of bearing steel to be fastened or attached, or the entire outer cylinder of the cylinder may be formed of bearing steel.

On the left side (left side of the figure) of the ball retainer, a stopper (14 in Fig. 1) for fixing the linear bushing is provided.

On one side of the stopper (14 in FIG. 1), a fastening screw is formed, and is configured to be fastened with the outer cylinder of the servo cylinder by using the formed screw.

The dust seal (12 of FIG. 1) is installed in the housing edge which the piston rod 11 reciprocates so that dust may not enter from the exterior.

The die bush (13 in FIG. 1) is fixedly installed between the dust seal 12 and the linear bushing 16 for smooth sliding of the piston rod 11.

An anti-rotation guide (19 in FIG. 1) is fixed to one side of the piston rod 11 located in the cylinder outer cylinder adjacent to the ball screw nut 20 to prevent rotation of the piston rod 11 for linear reciprocation. It is.

Since the outside of the anti-rotation guide 19 is selected to form one of a hexagon, a wing, a groove, a protrusion, and according to the shape to form a guide shape inside the outer cylinder of the servo cylinder, the anti-rotation guide 19 moves along the guide shape. The piston rod 11 is configured to perform a straight reciprocating motion without rotating.

More specifically, the anti-rotation guide 19 is fixedly installed with a bolt on one side of the piston rod 11 adjacent to the ball screw nut 20, and the polygonal shape, the wing shape, the groove on the outside of the anti-rotation guide 19 is provided. And one of the protrusions to form a shape.

Inside the servo cylinder outer cylinder which is in contact with the shape formed on the outside of the anti-rotation guide 18, a guide shape is formed in accordance with each shape formed on the outside of the anti-rotation guide 19 to perform a linear reciprocating motion along the guide shape by rotation of the motor. It is configured to.

The anti-rotation guide fixedly installed on one side of the piston rod consists of a structure having protrusions or grooves of various shapes, and forms a guide in the cylinder outer cylinder in accordance with the external shape of the anti-rotation guide and is fastened to each other when the piston is reciprocated. It is sufficient if the rod 11 does not rotate.

Preferably, the inner portion of the servo cylinder outer cylinder is molded into a 4 to 6 trillion polygonal structure to prevent rotation, and the anti-rotation guide is formed in the servo cylinder outer cylinder to form the anti-rotation guide to be fixed to one side of the piston rod. To install.

The range in which the anti-rotation guide 19 moves is equal to the distance that the ball screw nut moves and is made between the linear bushings 16.

In the upper part of the motor 22 fixedly installed on the right side of FIG. 1, a power connection terminal (23 of FIG. 1) is provided for supplying power to the motor 22.

As described above, the present invention is configured to linearly reciprocate the piston rod 11 by the ball rolling motion by the linear bushing can maintain a higher degree than the sliding type servo cylinder, it is possible to drive at high speed, the minimum By rolling resistance with frictional resistance can be obtained a light movement, there is an effect that can increase the durability.

Servo cylinder designed and manufactured according to the present invention is an electric actuator having a predetermined degree, for position control that can be applied to a logistics system such as an automobile assembly line, such as an actuator for a transfer system and an actuator for a clamping device, and a mixed flow production system of industrial automation. As a cylinder, it has a higher degree and rigidity than a sliding servo cylinder.

The range of the linear reciprocating motion of the servo cylinder is preferably 150 mm to 300 mm in consideration of the degree and shaking, but it is also possible to deform it to a range outside the design and manufacture it.

The range (torsion angle) of the torsion angle held by the anti-rotation guide is about ± 0.2 °.

Travel speed can be up to 1,000mm / sec.

The present invention is configured to convert the rotational motion of the motor to the linear motion of the piston rod by using the TM screw or ball screw nut, and to configure the piston rod in the housing in combination with the linear bushing to enable infinite linear movement, the housing and the rod The ball retainer is constructed to form a bearing steel with high rigidity, and guides the ball row to allow infinite linear movement in the housing.It is possible to control the torsion angle by applying an anti-rotation guide to control the angle to the torsion. It is highly industrially applicable because it is possible to provide a servo cylinder using a linear bushing that can maintain accuracy, obtain high durability, and enable high-speed driving.

Claims

In the servo cylinder,

A motor for rotating the screw shaft;

A screw shaft which is engaged with the rotating shaft of the motor to rotate;

A ball screw nut fastened in a linear reciprocating motion by rotating the screw shaft clockwise or counterclockwise;

A piston rod engaged with the ball screw nut and performing a linear reciprocating motion by a rotational motion of the motor; And

It supports the rotational movement of the motor to the screw shaft connected to the coupling firmly by the rotation bearing and the linear bushing for the linear movement of the piston rod which is connected to the ball screw nut for infinite linear movement. Servo cylinder.
The method according to claim 1,

The servo cylinder using the linear bushing is a rotation preventing guide and a guide inside the cylinder outer cylinder which are manufactured in accordance with the guide shape inside the cylinder outer cylinder for preventing rotation on one side of the piston rod capable of linear reciprocating motion coupled with a ball screw nut. A servo cylinder characterized by forming a shape.
The method according to claim 1,

The servo cylinder is a servo cylinder, characterized in that the outer cylinder in the linear bushing made of a bearing steel with excellent strength and durability in order to increase durability.
The method according to claim 1,

The servo cylinder is formed into a 4 to 6 trillion polygonal structure inside the servo cylinder outer cylinder to prevent rotation, and formed in the servo cylinder outer cylinder to form a rotation preventing guide in accordance with the shape of the 4 to 6 trillion polygonal structure on one side of the piston rod Servo cylinder characterized by fixed installation.