JP2000000730A - Refrigerating chuck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply a refrigerating chuck, having structure to incorporate a thermoelectric element utilizing a Peltier effect and cool the heat generation side of the element by the passage-through of cooling water, for a rotary type surface grinding machine. SOLUTION: A cooling water circuit 3 arranged peripherally of the lower part of a thermoelectric element incorporated in a refrigerating chuck is guided to the center on the back side of a chuck and connected to a double-constituted pipe for an output input channel inserted in orthogonal direction with the refrigerating chuck. Further, the pipe is connected to a pump and a cooling water tank 13 through a rotary joint 12 and water is supplied even during rotation of the chuck.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A refrigerating chuck equipped with a cooling element has the characteristic that it can be chucked irrespective of whether the work is a magnetic substance or a non-magnetic substance. Has a property that the temperature is low but the other side is very high. The present invention relates to the development of a freezing chuck having a mechanism for cooling such a refrigeration element and applicable to a vertical (rotary) surface grinding machine that performs processing while rotating a work.

[0002]

2. Description of the Related Art In a vertical surface grinding machine, chucking of a work is generally performed by burying an electromagnet in a mounting board and energizing the work. A cooling element, mainly a Peltier element, is buried in the work mounting plate, the work mounting plate is extremely cooled by energizing the cooling device, and the work placed thereon is frozen on the mounting plate and chucked. The method is adopted.

[0003] In this Peltier element, one side becomes extremely low temperature by energization, while the other side becomes extremely high. Therefore, it is necessary to efficiently cool the high temperature side of this element with a good chucking force. It is necessary to obtain.

Japanese Patent Application Laid-Open No. Hei 8-215966 developed and owned by the applicants of the present invention has developed a technology for cooling and removing heat generated by a cooling element using a cooling element. It is very difficult to flow cooling water while the freezing chuck is rotated, and it has been mainly used for a surface grinder in which a bed (or chuck) reciprocates.

[0005]

That is, the vertical surface grinder assumed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 8-215966 rotates a disk-shaped grinding wheel in the vertical direction, and moves the grinding wheel in a direction parallel to the rotation direction. The work was reciprocated and ground on the circumferential surface of the grindstone, and then the work was moved in a direction perpendicular thereto, and the reciprocation was repeated. In this vertical surface grinding machine, since the work mounting plate (chuck) simply repeats reciprocating motion, the cooling water pipe can be easily arranged, and the heat generation side of the thermoelectric cooling element embedded in the freezing chuck is provided. It was easy to perform cooling by passing water.

On the other hand, in a so-called rotary type vertical surface grinding machine that uses a cup-type grinding wheel and grinds the surface while rotating the work, a cooling water pipe that does not hinder the rotation of the freezing chuck. Pipes and connections are required, and it is necessary that no leakage occurs in the path of the cooling water.

[0007]

Means for Solving the Problems A cooling water circuit is provided around a circular substrate or the like which is made of a material having good thermal conductivity (Cu, Al, etc.), and both ends of the circuit are placed at the center of the substrate. And each end is connected to a double inlet / outlet pipe vertically inserted and fitted into a connection port opened at the center of the back surface side of the substrate, and the cooling side surface is located above the cooling water circuit. A thermoelectric element (hereinafter, referred to as a Peltier element) is provided so as to be able to conduct electricity so as to protrude substantially the same or several mm from the substrate surface,
A heat insulating material is placed on the upper surface so as to expose or cover the Peltier element, and a top plate made of a metal flat plate is placed thereabove and integrated with the substrate in a tightly integrated manner. A rotary joint is attached to the lower end of the double pipe line so that the pipe can be rotated without any trouble even if the pipe is connected to the cooling water tank.

[0008] Further, both ends of a cooling water circuit provided around the substrate of the freezing chuck are connected to a double inlet / outlet pipe, and a water pipe at one end is connected to a cooling water tank via a rotary joint. The side water pipe was further connected to a cooling water tank via a suction pump.

[0009]

According to the first aspect of the present invention, even when the freezing chuck is rotating, the cooling water flows in the cooling water circuit formed immediately below the cooling element, and the heat generated on the high-temperature side of the Peltier element always remains outside the chuck device. To improve the refrigeration efficiency on the surface side.

According to a second aspect of the present invention, the flow of the cooling water is performed by the suction pump, so that the inlet / outlet water channel, the inside of the cooling water circuit, and the inside of the rotary joint are in a negative pressure state.
Even if the sliding performance of the rotary joint deteriorates due to wear or the like, there is no leakage of cooling water.Therefore, stable cooling is achieved without adverse effects such as flooding on the vertical surface grinder. Work efficiency can be improved.

[0011]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a central longitudinal sectional view showing a main part of a state in which a refrigeration chuck according to the present invention is mounted on a bed of a vertical surface grinding machine, and FIG. 2 is a plan view of the refrigeration chuck.

As shown in FIG. 1, a cooling water circuit 3 is provided inside a substrate 2 having a shape such as a circle of a freezing chuck body 1.
Is formed in a circuit or the like, and both ends of the circuit are guided to the center of the substrate and the vicinity thereof, for example, as shown in FIG. 2, and become a double tube vertically inserted and fitted into the center opening on the back side. It is connected to the double pipe 4 for incoming and outgoing water. The passage, for example,
The inside diameter of the inner pipe of the inlet / outlet double pipe 4 is defined as an inlet (or outlet) cooling water passage 6, and the portion enclosed by the inner diameter of the outer diameter pipe and the outer diameter of the inner pipe is the outlet side (or inlet). Side) passage 5.

A plurality of Peltier elements 7 are mounted above the cooling water circuit 3 with their cooling side surfaces flush with the upper surface of the substrate, and the upper surface is covered with a heat insulating plate 8, for example, a plastic film or the like. , Peltier element surface several mm
A heat insulating material (not shown), which is mounted in a protruding manner and surrounds the periphery of the Peltier element 7 and has a cutout window opened so that only the surface thereof is exposed, is coated on the substrate. Further, a top plate 9 made of a metal plate is superimposed on the upper surface thereof, and the substrate 2, the heat insulating plate 8 and the top plate 9 are integrated by fastening bolts 10 or the like.

It is desirable that the heat insulating plate 8 coated on the upper surface of the Peltier element 7 has an extremely small thickness, and that the surface of the Peltier element 7 is in close contact with the heat insulating plate 8 and the top plate 9. is necessary. Also, the Peltier element 7
In a configuration in which the heat insulating plate 8 is not covered on the upper surface of the Peltier element, it is necessary to adhere a conductive paint or the like to the upper surface of the Peltier element to achieve close contact with the top plate 9.

FIG. 1 shows the principle of the method for energizing the Peltier element 7 described above. Each element is connected in series or in parallel and the wiring is led out of the freezing chuck to form a vertical die. A sliding contact 11 is made with a circular electrode 21 formed on the outer periphery of a chuck mounting plate 20 of a surface grinding machine. The connection between the spiral electrode 21 and the power supply is not shown. In addition, as long as the connector is capable of slidingly contacting the power supply without interruption during the operation of the vertical surface grinding machine, that is, during the rotation of the freezing chuck, the method is of course not questionable. It is also possible to use a rotary connector "RJP series" or the like handled in sales.

The refrigeration chuck 1 having the above structure is mounted on a chuck mounting plate 20 of a vertical surface grinding machine, and is attached 10 by bolts or the like. This chuck mounting plate 20
Has a through hole at the center thereof, through which a double inlet / outlet water pipe 4 attached to the lower surface of the freezing chuck 1 is inserted and protrudes downward. Rotary joint 12 (for example, Showa Giken Kogyo A
CF type) is connected to each of the cooling water passages 5, 6
Is connected to the cooling water tank 13 via the discharge side nipple 5a and the supply side nipple 6a. A detent part 12a formed at one end of the body of the rotary joint 12 is attached to an appropriate position 22 of the vertical surface grinder so that the nipple part remains stationary in a certain direction despite the rotation of the double pipe 4. Will do. The chuck mounting plate 20 has a shaft portion inserted through a bearing hole of the column C via a bearing B, and rotatably connects a pulley P2 mounted below the pulley P2 and a pulley P1 mounted to the motor M via a belt. Have been. G is a grindstone and W is a work.

A pump 13 is connected between the discharge side nipple 5a and the cooling water tank 13 in a direction to suck cooling water from a cooling water circuit side in the freezing chuck. As a result, the inside of the cooling water circuit becomes negative pressure and is discharged to the cooling water tank 13 with pressure. In addition, it goes without saying that a water supply pump may be connected to the supply side nipple 6a to flow water in a pressurized state.

The refrigeration chuck according to the present invention having the above-described structure includes:
Due to power transmission from a power supply (not shown), the upper surface side of the Peltier element becomes low temperature, and the lower surface side generates heat and becomes high temperature. Therefore, the top plate of the freezing chuck 1 is cooled, and the work placed thereon is frozen on the top plate and is not easily separated, that is, chucked.

On the other hand, the cooling water in the cooling water tank 13 is sucked into a cooling water circuit by a water suction pump to cool the substrate.
At the same time, the Peltier element having the heat-generating side contacted with the substrate is cooled because the substrate loses heat. As described above, the cooling water flows even when the work mounting plate 20 and the freezing chuck 1 of the vertical surface grinding machine are rotating.

[0020]

According to the refrigeration chuck of the present invention having the above-described structure, when the chuck mounting plate 20 of the vertical surface grinding machine, and thus the refrigeration chuck is rotating, power is supplied to the Peltier element to the orbital electrode portion. The top plate 9 is constantly cooled by the contact 11 of the terminals, and the back side of the Peltier element is cooled by cooling water passing through a cooling water circuit from a cooling water tank via a rotary joint. In addition, since the cooling water circuit system, particularly the liquid-tight failure due to abrasion of the rotary joint, does not leak through the pump on the drain side, maintenance and management thereof are facilitated.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional view showing a state in which a freezing chuck according to the present invention is mounted on a mounting plate of a vertical surface grinding machine.

FIG. 2 is a plan view of a freezing chuck.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Freezing chuck main body 2 Substrate 3 Cooling water circuit 4 Double pipeline for water inflow / outflow 5 Cooling water passage 6 Outlet side passage 7 Peltier element 8 Insulation material 9 Top plate 12 Rotary joint 13 Cooling water tank 21 Circular electrode

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[Procedure amendment]

[Submission date] June 19, 1998 (1998.6.1)
9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION A refrigerating chuck equipped with a cooling element has the characteristic that it can be chucked regardless of whether the work is a magnetic substance or a non-magnetic substance. Has a property that the temperature is low but the other side is very high. A mechanism for cooling such a refrigeration element is provided, and
The present invention relates to the development of a freezing chuck applicable to a vertical (rotary) surface grinder that performs processing while rotating a work.

Claims (2)

[Claims] 1. A cooling water circuit is provided around a circular substrate,
Both ends of the circuit are guided to the center of the substrate and the vicinity thereof, and connected to a double conduit for incoming and outgoing water composed of a double pipe vertically inserted and fitted into an opening at the center of the rear surface of the substrate. The Peltier element is disposed so as to be able to conduct electricity so that the cooling side surface projects substantially the same or several mm above the substrate surface, and a heat insulating material is mounted on the upper surface so that the Peltier element is exposed or covered. And a top plate made of a metal flat plate is placed thereon, and is integrated closely with the substrate, and a rotary joint is attached to the lower end of the double channel for incoming and outgoing water. Freezing chuck for surface grinder. 2. A cooling water circuit, which is provided around a substrate of a freezing chuck, is connected at both ends to a water inlet / outlet double pipe line, and a water pipe at one end is connected to a cooling water tank via a rotary joint. 2. The freezing chuck for a vertical surface grinding machine according to claim 1, wherein the side water pipe is further connected to a cooling water tank via a suction pump.