JPH11143545A - Positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress heat influence from a supporting object whose temperature rises to a linear scale tape and to perform positioning with accuracy. SOLUTION: A thermal conductive layer 21 which has higher thermal conductivity than a linear scale tape 7 and a supporting body 1 is provided between them, a heat radiating part 22 by passing air is also provided at a projecting part 21a which projects more than the tape 7 of the layer 21 and heat influence to the tape 7 is suppressed by radiating heat A from the body 1 through the layer 21 and the part 22 accompanied with air-passing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device, and more particularly, to a support having a guide for guiding a moving body, a linear scale graduation having moving position information of the moving body is stuck to the moving body. It relates to a positioning device in which a linear sensor provided at a position reads a position information of a moving body according to a positional relationship with a linear scale scale, and controls a position.For example, an electronic component is mounted on a circuit board and an electronic circuit board is mounted. It is used for positioning a moving body and a support in manufacturing.

[0002]

2. Description of the Related Art In a component mounting apparatus for mounting electronic components on a circuit board (including mounting requiring post-processing such as mounting and subsequent reflow soldering), for example, suction nozzles and chucks for handling electronic components are used. Due to the relative movement between the mounting head having the component handling tool and the component supply unit that supplies various electronic components, the mounting head handles the selected one of the various electronic components to be supplied each time it is necessary. The electronic component is picked up by a tool, and then mounted on a predetermined position of the circuit board by relative movement between the mounting head and a circuit board to be mounted.

[0003] In order to prevent mishandling and mounting of electronic components, the relative movement in each of these parts can be prevented even if any of the component supply unit, the mounting head, and the support of the circuit board is a moving body. An accurate positioning function is required.

[0004] Conventionally, to satisfy this, FIG.
Referring to (b), an encoder e is provided on a drive motor d that drives a screw shaft c that moves the moving body a straight on the support b, and the encoder e determines the amount of rotation of the motor d at each time. Detecting and determining the moving position of the moving body a,
It can be positioned at the required position.

[0005]

By the way, recently,
With the miniaturization of chip components, the advance of integrated circuits, and the development of connectors, electronic components are becoming more diversified and larger. For this reason, it is necessary for the component mounting apparatus to handle electronic components of various types, forms, shapes, and sizes. There is a demand for further improvement in positioning accuracy.

In order to respond to this, when the moving body a is linearly moved on the support b by the screw shaft c as shown in FIGS. 4A and 4B, and in FIG. As shown in b), the moving body a moves on the support b with the magnet f1 and the coil f.
In any case where the linear movement is performed by the linear motor f composed of the linear scale tape g, the linear scale tape g
It is conceivable to position the moving body a with high accuracy by reading the position information held by the linear sensor h provided on the moving body a.

As a result, the present inventors have conducted various experiments and studied repeatedly, and as a result, there has been a limit to the improvement of the positioning accuracy even by the linear scale. This is because the guide part i for guiding the moving body a of the supporting body b is heated by friction when the moving body a moves, and the heat j at that time is moved from the supporting body b to the linear scale as shown in FIG. This is because the thermal expansion of the tape g by a certain amount δx causes a deviation in the absolute position of the linear scale tape g. When the driving unit is the nilia motor f shown in FIGS. 6A and 6B,
The heat generated by the coil f2 is large, which is also a problem because it also has a thermal effect on the linear scale tape g.

An object of the present invention is to provide a positioning device capable of performing high-precision positioning by suppressing the thermal influence from the supporting body that rises in temperature to the scale of the niria scale based on such new knowledge. .

[0009]

In order to achieve the above object, the present invention provides a support having a guide portion for guiding a moving body so as to move in a straight line. A linear scale graduation body attached to the moving body, the position information of the linear scale graduation body is read from a positional relationship at each time by a niria sensor provided on the moving body, and the driving unit moves the moving body to a predetermined position. A heat conductive layer with higher thermal conductivity is provided between the linear scale scale and the support, and a heat radiating part by ventilation is provided at the overhang of the heat conductive layer from the linear scale scale. This is one of the features.

In such a configuration, even when the moving body is driven by the driving unit and moves straight along the guiding unit, the temperature of the guiding unit rises due to friction, and the heat at that time reaches the support of the moving body. , A heat conductive layer with better heat conductivity than those located between the support and the linear scale graduation attached to it, as soon as it receives heat from the support, conducts it to the entire heat conductive layer, Since heat is rapidly radiated with ventilation at the heat radiating portion provided at the portion of the heat conductive layer that protrudes from the linear scale scale, most of the heat received by the heat conductive layer is radiated from the heat radiating portion. The heat from the support can be suppressed from reaching the linear scale scale, and the absolute position of the linear scale scale can be secured well and highly accurate positioning can be performed based on the position information read by the linear sensor. The present invention is further characterized in that the heat radiating portion is a fan having a finned outlet or a suction port at a mounting portion on the heat conductive layer side.

According to this, the fan receives heat from the heat conductive layer at the fin-shaped outlet or suction port on the side of the heat conductive layer, diffuses the heat into the fin portions, and easily radiates heat. Since the fins are forcibly cooled by ventilating the outlet or suction port, the heat dissipation of the portion of the heat conductive layer that protrudes from the nilia scale scale is enhanced, and the thermal effect from the support to the linear scale scale is reduced. Further, the positioning accuracy can be further improved.

The present invention is also characterized in that, in each case, the heat radiating portion is provided at a portion protruding from both ends in the longitudinal direction of the linear scale scale.

Accordingly, the heat conductive layer quickly radiates the heat of the portion corresponding to the entire length of the linear scale scale from both ends thereof, so that even if the linear scale scale is long,
The thermal effect on the central part can be sufficiently suppressed,
Highly accurate positioning is possible.

According to the present invention, in each case, when the heat conductive layer is made of carbon graphite, the degree of heat radiation from the heat radiating portion of the heat from the support of the heat conductive layer is further increased by its high heat conductivity. The thermal effect from the support to the linear scale scale can be further suppressed, and the positioning accuracy can be further improved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings together with the embodiments.

In this embodiment, for simplicity of explanation, FIG.
In each of the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. 2, the moving body 2 is linearly moved in the uniaxial direction by the driving unit 10 on the support 1. The present invention includes a case in which the present invention includes a case where the movable body 2 is moved in a straight line and includes a support 1 having a guide portion 3 which is heated by the movement of the moving body 2. It is effective to apply.

In both the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. 2, a rail-shaped guide 3 is provided on both side walls 1a of the channel-shaped support 1, and the guide 3 is moved to the guide 3. The slider portion 2a of the body 2 is fitted so as to move straight. A linear scale tape 7, which is an example of a nilia scale scale, is attached to an outer surface of, for example, one side wall 1 a of the support 1, and positional information held by the linear scale tape 7, for example, in a moving direction of the moving body 2. An optical or magnetic linear sensor 8a corresponding to the type of the position information provided in the read head 8 attached to the moving body 2 has a corresponding position scale by light or magnetism in the longitudinal direction.
Thus, the position of the moving body 2 at each time can be detected. Based on this, the driving unit 10 can be controlled to move the moving body 2 to any position, stop, and position. The linear scale graduation may be appropriately selected from tapes, sheets, and the like, if necessary.

In each of the first and second embodiments shown in FIGS. 1 and 2, the moving body 2 of the present embodiment is of a table type, and picks up various electronic components to be supplied. By installing a work head with a component handling tool that performs various tasks such as mounting the picked up electronic components on the circuit board, positioning it at the required position each time, so that the predetermined work can be performed, Conversely, it is possible to place a work object to be worked, such as a circuit board on which electronic components are mounted, and move it to a required position each time to receive a work such as mounting components. In the case of the working head, the moving body 2 itself can be used without being placed on or attached to the moving body 2.

In the first embodiment shown in FIG. 1, the driving section 10 vertically passes ball screws 4 for moving the moving body 2 by rotation into the grooves 1b of the supporting body 1, and inserts the ball screws 4 at both ends of the supporting body 1. The moving body 2 is reciprocated and linearly moved on the support body 1 by rotating the ball screw 4 in both forward and reverse directions by a motor 6 mounted on one of the bearing members 5. ing.

In the second embodiment shown in FIG. 2, the driving unit 10 arranges the magnets 11a at the bottoms of the grooves 1b of the support 1 in the moving direction of the moving body 2, while providing the magnets 11a at the lower part of the moving body 2. The linear motor 11 is constituted by both of them, and the moving body 2 is reciprocated and linearly moved on the support 1 by controlling the energization of the coil 11b.

By the way, when the moving body 2 is moved by the drive unit 10, the temperature of the guide unit 3 for guiding the moving body 2 rises due to both frictions irrespective of the specific structure.
At that time, the heat spreads over the entire support 1 and also causes the linear scale tape 7 attached to the surface thereof to thermally expand, so that the absolute position of the linear scale tape 7 cannot be secured, and an error occurs in the positioning. In addition, various operations such as mounting electronic components cannot be performed with high positional accuracy. In the case where the drive unit 10 is a linear motor 11 as in the second embodiment, the heat generated by the coil 11b is large, which also affects the linear scale tape 7 by affecting the support 1, which is a particular problem.

In the present embodiment, in order to solve such a problem, in both the first and second embodiments, the thermal conductivity between the linear scale tape 7 and the support 1 is higher than that between the linear scale tape 7 and the support 1. A high heat conductive layer 21 is provided, and a heat radiating part 22 by ventilation is provided on a protruding part 21 a of the heat conductive layer 21 which protrudes from the linear scale tape 7. Thereby, the friction when the moving body 2 is driven by the drive unit 10 to move straight along the guide unit 3 and the coil 1 of the linear motor 11
1b, the guide portion 3 and the support 1 rise in temperature, and even when the heat reaches the support 1 of the moving body 2, the position between the support 1 and the linear scale tape 7 affixed thereto is increased. As shown in FIG. 3, when the heat conductive layer 21 having better heat conductivity than the heat conductive layer 21 receives the heat A from the support 1, the heat conductive layer 21 is quickly conducted and diffused throughout the heat conductive layer 21 as shown by an arrow. The heat radiating portion 22 provided in the portion 21a of the heat conductive layer 21 which protrudes beyond the linear scale tape 7 is radiated quickly as shown by the arrow with the ventilation. Most of the heat radiation part 22
Of the linear scale tape 7, including the case where the drive unit 10 is a linear motor 11 that generates heat with the coil 11 b, including the case where the drive unit 10 is a linear motor 11 that generates heat with the coil 11 b. The position can be secured well and highly accurate positioning can be performed based on the position information read by the linear sensor 8a.

In the first and second embodiments, the heat radiating section 22
The fan 24 has a blowout port or a suction port 23 provided with a fin 23 a at a mounting portion on the heat conductive layer 21 side.

By doing so, the fan 24 receives the conduction of heat A from the heat conductive layer 21 to the outlet or suction port 23 with the fins 23a on the heat conductive layer 21 side and diffuses the heat A into the respective fins 23a. Further, while the heat is easily radiated, the fins 23a are ventilated through the air outlet or the air inlet 23 as shown by a dashed arrow or in the opposite direction.
Since the part is forcibly cooled, the heat dissipating property at the portion 21a of the heat conductive layer 21 protruding from the linear scale tape 7 is enhanced, the thermal influence on the linear scale tape 7 from the support 1 is further suppressed, and the positioning accuracy is further improved. This is particularly effective when the linear motor 11 is used.

In addition, since the heat dissipating portion 22 is provided in the portion 21a of the heat conductive layer 21 projecting from both ends in the longitudinal direction of the linear scale tape 7, the heat conductive layer 21 corresponds to the entire length of the linear scale tape 7. Since the heat A of the portion is quickly radiated from both ends thereof, even if the linear scale tape 7 is long, the thermal influence on the central portion can be sufficiently suppressed, and highly accurate positioning can be performed. However, if necessary, the heat conductive layer 21 is provided with an overhang portion 21a on the side of the linear scale tape 7 in the longitudinal direction,
The heat dissipating portion 22 may be provided there, and the heat dissipating as described above can be achieved even in the middle of the heat conductive layer 21 in the longitudinal direction. After all, the heat dissipating portion 22 may be provided at any position as necessary, and the number of the heat dissipating portions 22 can be freely set.

The heat conductive layer 21 is preferably made of carbon graphite.
The degree of heat dissipation from the heat radiating portion 22 of the heat conductive layer 21 from the support 1 can be further increased, the influence of the heat on the linear scale tape 7 from the support 1 can be further suppressed, and the positioning accuracy can be further improved. However, other known or newly provided materials may be substituted as long as the object is achieved.

Although the heat conductive layer 21 may be provided in any manner, it is preferable that a sheet-shaped member is adhered to the workability and durability.

[0028]

According to one feature of the present invention, the absolute position of the linear scale is sufficiently secured by suppressing the heat from the support to the linear scale, and the linear scale is linearly moved from the linear scale. High-precision positioning can be performed based on the position information read by the sensor.

According to a further feature of the present invention, the heat dissipating property at the portion of the heat conductive layer protruding from the nilia scale scale is enhanced by forced cooling using fins and ventilation, so that the heat from the support to the linear scale scale is improved. The influence can be further suppressed, and the positioning accuracy can be further improved.

According to still another feature of the present invention, even if the linear scale is long, the thermal influence on the central portion thereof can be sufficiently suppressed, and highly accurate positioning can be performed.

According to still another feature of the present invention, the degree of heat dissipation from the heat radiating portion of the heat conductive layer is further increased by the high thermal conductivity of the heat conductive layer. The influence of heat on the positioning can be further suppressed, and the positioning accuracy can be further improved.

[Brief description of the drawings]

FIGS. 1A and 1B show a first example of an embodiment of the present invention, in which FIG. 1A is an overall perspective view, and FIG. 1B is a partial plan view.

FIG. 2 is an overall perspective view showing a second example of the embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a plan view of a heat radiating mechanism between the support and the linear scale tape in the embodiment of the present invention.

FIGS. 4A and 4B show a first prior example considered prior to the present invention, wherein FIG. 4A is an overall perspective view, and FIG. 4B is a partial plan view.

FIGS. 5A and 5B show a second prior example considered prior to the present invention, wherein FIG. 5A is an overall perspective view and FIG. 5B is a partial plan view.

FIG. 6 is an explanatory diagram showing a plan view of a mechanism for transferring heat from the support to the linear scale tape in the first and second prior art examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support body 2 Moving body 3 Guide part 7 Linear scale tape 8a Linear sensor 10 Drive part 21 Heat conductive layer 21a Overhang part 22 Heat radiating part 23 Outlet or suction port 23a Fin 24 Fan A Heat

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Osamu Okuda, Inventor 1006 Odakadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A linear scale graduation having moving position information of a moving body is attached to a support having a guide portion for guiding the moving body to move straight, and a linear sensor provided on the moving body is used. A positioning device that reads the position information of the linear scale scale from the positional relationship at each time, and based on this, the driving unit moves the moving body to a predetermined position. A positioning device, comprising: a heat conductive layer having a higher heat conductivity than the heat conductive layer; and a heat radiating portion provided by ventilation in a protruding portion of the heat conductive layer protruding from the linear scale scale. 2. The positioning device according to claim 1, wherein the heat radiating portion is a fan having a finned outlet or a suction port at a mounting portion on the heat conductive layer side. 3. The positioning device according to claim 1, wherein the heat radiating portion is provided at a portion of the heat conductive layer protruding from both ends in the longitudinal direction of the linear scale scale. 4. The positioning device according to claim 1, wherein the heat conductive layer is made of carbon graphite.