JPH06100406B2 - Entrance / exit structure of constant temperature bath - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Use of the Invention] The present invention relates to an inlet of a low temperature oven provided in an IC handler,
And the structure of the outlet.

[Background of the Invention] An IC handler is an automatic machine that sequentially conveys a large number of ICs, attaches the ICs to a measurement socket, detaches the ICs, and then sorts and ejects the ICs based on the measurement results. .

The above measurement conditions are determined based on the specifications of the IC to be measured. Regarding the temperature condition for measurement, there are cases where the temperature is higher than room temperature (for example, 160 ° C.), there are cases where it is room temperature, and there are cases where it is low temperature (for example −40 ° C.). Therefore,
The IC handler is usually provided with a high or low temperature constant temperature bath.

A chute rail is often used for IC transportation in the IC handler. The ICs to be handled include various types such as thick type, thin type and PLCC type. Fig. 5 is a perspective view of a thick IC1 being transported by a chute rail, Fig. 6 is a perspective view of a thin IC1 'being transported, and Fig. 7 is a PLCC.
FIG. 9 is a perspective view showing a state where the mold IC1 ″ is being conveyed.

The above shoot rails are generally installed with an inclination, and
In many cases, it is slid by gravity, but it may be installed vertically or horizontally. When the chute rail is installed horizontally, an appropriate transport driving unit such as a claw feeding unit is provided.

FIG. 4 shows an example of a low temperature constant temperature bath generally used conventionally and shows a cross section near the inlet.

Liquefied nitrogen is fed into the constant temperature bath 2 through a pipe 3 to keep the temperature of the bath at -40 ° C.

The chute rail 4 is installed so as to pass through the inlet opening 2b provided in the wall 2a at the end of the constant temperature bath 2,
Guide ICs 1a, 1b to 1f as shown by arrows a, b, c.

Reference numeral 5 denotes a shutter installed so as to cover the entrance opening 2b, which is opened only when the IC passes and closed when the IC does not pass. The opening / closing drive of the shutter 5 is performed by an automatic control mechanism (not shown) based on the output signal of a sensor (not shown) that detects passage of the IC.

The inside of the constant temperature bath 2 is kept at a slightly positive pressure (for example, several mbar higher than the atmospheric pressure) so that the outside air does not flow into the constant temperature bath 2.

For this reason, it is inevitable that a slight gas leak will occur from the location where the shutter 5 is provided, as indicated by the arrow d.

Since the leaked gas has a temperature of -40 [deg.] C., frost may adhere to the shutter 5 to hinder its opening / closing operation. Such a problem also occurs near the exit of the shoot rail 4 penetrating the constant temperature bath 2.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and is intended to provide an entrance / exit structure in which there is no risk of frost adhering to the shutter of the entrance and exit of the constant temperature tank and freezing, and further the shutter can be omitted. is there.

[Outline of Invention]

In order to achieve the above object, the entrance / exit structure of the present invention is an IC handler in which a carrier path for an IC is provided by penetrating a thermostat at a temperature lower than room temperature, and the carrier path penetrates a wall of the thermostat. A pipe is provided along the upper edge of an opening provided at a location, a nozzle hole for ejecting air is provided in the pipe, and the pipe is rotatably supported about a central axis and It is characterized in that means for pumping dry air is provided in the pipe.

Example of Invention

Next, one embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a cross-sectional view showing one embodiment of the constant temperature bath inlet / outlet structure of the present invention.

2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is an enlarged detailed view of the same section III.

This embodiment is obtained by applying the present invention to the conventional example shown in FIG. 4 to improve it. ICs 1a to 1f, a constant temperature chamber 2, a pipe 3 and a chute having the same drawing reference numbers as in FIG. The rail 4 is a component similar to or similar to that in the conventional example.
In this embodiment, the shutter 5 is not provided.

As shown in FIG. 2, in this embodiment, five chute rails 4 _-5 , 4 _-2 to 4 _-5 are installed in parallel. 1a _-1 ~ 1
a- ₅ is an IC carried by each of the above chute rails.

As shown in FIG. 1, the pipe 6 is arranged along the upper edge of the inlet opening 2b. Reference numerals 7 and 7'indicate bearings that rotatably support the pipe 6 (see FIGS. 2 and 3). The pipe 6 is provided with through holes (nozzle holes) 6a for ejecting air.

The arrow A shown in FIG. 3 represents the air ejection direction. When the pipe 6 is rotated with respect to the bearing 7, the air ejection direction arrow A can be freely adjusted. Although not shown, the bearing 7 is provided with means for restraining the rotation of the pipe 6.

Although not shown, the bearing 7 has a swivel joint function with respect to the pipe 6, and is configured so that dry air can be pressure-fed into the pipe 6 via the swivel joint function. Pressure adjusting means is provided.

Even in the conventional apparatus (FIG. 4), an attempt was made to blow dry air to the shutter 5 in order to prevent the shutter 5 from freezing due to frost. Also, since there is no means for adjusting the pressure, especially the direction, the blowing of dry air had to be stopped when the shutter 5 was opened to pass the IC. The reason is that the IC is transported while it continues to be blown with dry air (carrying into the constant temperature chamber 2).
This is because there is a risk that the IC blows back or is blown away by the wind pressure.

According to the experiments conducted by the inventor of the present invention, it is possible to find a state in which the IC is not conveyed by the dry air flow by appropriately selecting the flow velocity and flow rate of the dry air to be jetted and adjusting the jetting direction appropriately. The appropriate conditions described above can be easily reproduced by experimentally obtaining them.

In particular, experiments have confirmed that when the IC type changes (when the shape, size, and weight change), adjustment can be made by adjusting the direction of the dry air ejection.

In order to use the embodiment of the present invention (FIGS. 1 and 2), liquefied nitrogen is supplied from the pipe 3 into the constant temperature bath 2 to bring the constant temperature bath 2 into consideration.
While maintaining the inside at -40 ℃, the through hole (nozzle hole) 6a of the pipe 6
The dry air is ejected from the IC, and the ejection direction arrow A is applied to the IC.
Adjust in the proper direction according to the model.

In the above state, the IC transportation is not hindered, and moreover,
Due to the air curtain effect of the jet stream of dry air, the inside of the thermostatic chamber 2 and the atmosphere are shut off. Therefore, there is no risk of dew condensation or freezing near the inlet / outlet of the constant temperature bath, and the inside of the constant temperature bath 2 is maintained at the target temperature. Further, due to the above-mentioned air curtain effect, even if the shutter 5 is omitted as in the present embodiment, the condition keeping in the constant temperature bath 2 is not adversely affected.

As is clear from FIGS. 1 to 3, the inlet structure of this embodiment is extremely simple and therefore the manufacturing cost is low. In addition, the dry air does not require control such as stopping or jetting, and the jetting can be performed continuously even under the same conditions, so control is easy.

When the type of IC being transported is changed, the pipe 6 can be rotated to adapt quickly and easily.

In the present embodiment (FIG. 1), the inlet structure of the thermostatic chamber 2 is described. However, when the IC carrying direction arrows a, b, and c are reversed left and right, this is applied to the outlet of the thermostatic chamber 2 at this time. (In this case, the inlet opening 2b in the figure will be referred to as the outlet opening.

〔The invention's effect〕

As described in detail above, when the present invention is applied, there is no risk of frost adhering to the shutter of the low temperature constant temperature bath inlet / outlet portion and freezing,
Furthermore, it is possible to omit the installation of the shutter without adversely affecting the function of the constant temperature bath. By omitting the shutter, the drive and control system of the shutter is also omitted, so the structure is remarkably simplified, which not only contributes to the reduction of equipment costs and maintenance and maintenance man-hours but also prevents troubles related to the operation of the shutter. It greatly contributes to the reliability improvement of the IC handler.

[Brief description of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is an enlarged detailed view of the same section III. FIG. 4 is a sectional view showing a conventional constant temperature tank inlet / outlet structure.
5 to 7 are perspective views showing a state in which the ICs are being conveyed by the chute rails. 2 ... Constant temperature bath, 2b ... Entrance opening, 4 ... Shoot rail, 5 ... Shutter, 6 ... Pipe, 6a ... Nozzle hole,
7,7 ′ …… Bearing.

Claims (1)

[Claims] 1. A constant temperature tank for an IC handler, which is provided with a plurality of rows of parallel IC chute rails so as to pass through a constant temperature tank at a temperature lower than room temperature. A pipe is provided along the upper edge of the opened opening, a nozzle hole for ejecting air is provided in the pipe, and the pipe is rotatably supported around a central axis and is provided in the pipe. An inlet / outlet structure for a thermostatic chamber, characterized by being provided with means for feeding dry air.