JP2012043952A - Enclosed control board for machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an enclosed control board for a machine tool with an openable lid in order to prevent intrusion of oil mist or dust into the control board.SOLUTION: A control board comprises: a housing 11 which shields a heat generating control apparatus 31 used in a machine tool from the outside; and an openable door 12. The control board further comprises: a variable volume bag body 41 installed in the control board and having a bag body opening 42 communicating with the outside of the control board; and a pressure valve 51 which acts only in the direction of discharging air in the control board to the outside thereof. The variable volume bag body 41 varies the volume of the bag body 41 to eliminate pressure difference between the inside and outside of the control board.

Description

  The present invention relates to a machine tool control panel having a lid that can be freely opened and closed, and to a machine tool hermetic control panel for preventing oil mist and dust from entering the control panel.

  The ambient air around the machine tool contains oil or oil mist generated during cutting or grinding, or dust, chemicals, water, water vapor, etc., and the machine tool is often in a bad environment. In addition, chip conveyors and coolant tanks are often installed adjacent to machine tools, and the atmosphere constantly contains oil mist due to evaporation from the machine tools. If oil mist or dust accumulates in the control equipment for many years, it may cause a short circuit or disconnection due to corrosion, causing trouble.

One of the causes of oil mist and dust entering the control panel is a pressure change due to a temperature change in the control panel. The pressure in the control panel fluctuates due to temperature changes in the control panel that occur when the machine tool is turned on and off.
When the control panel is poorly sealed, air in the control panel and outside air come in and out due to pressure changes in the control panel, and oil mist and dust are sucked into the control panel together with the outside air. The higher the control panel is sealed, the smaller the inflow of outside air into the control panel and the outflow of air from the inside of the control panel to the outside of the control panel. In order to counter this pressure change in the control panel, the rigidity of the control panel becomes important. As described above, in order to prevent oil mist and dust from entering the control panel, airtightness and rigidity are important.

Patent Document 1 discloses a technique in which an oil mist is not allowed to enter a control panel by opening an opening in the control panel and attaching an air filter, even if outside air is inhaled due to a temperature change in the control panel.
Patent Document 2 discloses a technique for relaxing a pressure difference from the outside of the control panel by opening an opening in the control panel and closing it with a bag.
In Patent Document 3, a pressure adjusting member having an air filter attached to a bag body is attached to an opening of a control panel, and a bag body is used for a sudden pressure change, and a mist is prevented from entering by a air filter for a gradual pressure change. Is disclosed.

JP 2007-165793 A JP 2003-229679 A JP 2000-208948 A

  However, since the technique disclosed in Patent Document 1 uses an air filter, a very fine air filter is required to prevent oil mist. In order to suck outside air from a fine air filter, a large pressure difference is required, and there is a possibility that the air is sucked not from the air filter but from the gap of the control panel. Further, if the air filter is used to prevent the oil mist from entering, the oil mist is liquefied. Continued use without replacing the air filter may cause liquefied oil to enter the control panel.

In the technique disclosed in Patent Document 2, when opening and closing the door of the control panel for maintenance / inspection or the like, depending on how the door is opened / closed, there is a possibility that when the door is closed, there is almost no air inside the bag. is there. When the pressure in the control panel rises, the pressure difference in the control panel cannot be relieved only with air in the bag, and the pressure in the control panel rises and stresses the control panel.
In the technique disclosed in Patent Document 3, as in the technique disclosed in Patent Document 1, since an air filter is used, oil mist may be liquefied and enter the control panel.

  Therefore, in view of the above-described problems of the conventional technology, the object of the present invention is to adjust the pressure in the control panel to suppress the entry of outside air into the control panel, and to accumulate oil mist and dust in the control equipment in the control panel. It is to provide a hermetic control panel for machine tools that can prevent the above.

  The invention according to claim 1 of the present application is a control panel having an openable / closable door for shielding an exothermic control device used in a machine tool disposed therein from the outside, and is installed inside the control panel. A variable volume bag body having an opening communicating with the outside of the control panel; and a pressure valve that acts only in a direction in which air inside the control panel is discharged to the outside of the control panel. The bag body is a control panel that is adjusted so as to eliminate a pressure difference between the inside and the outside of the control panel by changing the volume of the bag body.

2. The control panel according to claim 1, further comprising a mechanism for exhausting air inside the variable volume bag body to the outside when the door of the control panel is open. It is.
The invention according to claim 3 is the control panel according to any one of claims 1 and 2, further comprising a protective cover that covers the variable volume bag.
The invention according to claim 4 is the control panel according to any one of claims 1 to 3, wherein the volume-variable bag body is installed in a separate chamber inside the control panel.
The invention according to claim 5 is characterized in that the opening is provided with a filter for preventing chips from entering into the bag with variable volume. It is a control panel.

The invention according to claim 6 is the control panel according to any one of claims 1 to 5, wherein the variable volume bag body has oil resistance.
The invention according to claim 7 is the control panel according to any one of claims 1 to 6, wherein the volume-variable bag body has a bag shape.
The invention according to claim 8 is the control panel according to any one of claims 1 to 6, characterized in that the volume-variable bag body has a bellows shape.
According to a ninth aspect of the present invention, when the variable volume bag is disposed inside the control panel, the opening communicating with the outside of the control panel is positioned at the lowermost part of the variable volume bag. The control panel according to any one of claims 1 to 8, wherein
The invention according to claim 10 is characterized in that an oil mist sensor is installed in the vicinity of the inside of the control panel and outside the variable volume bag body. It is a board.

  According to the present invention, there is provided a closed control panel for machine tools capable of adjusting the pressure in the control panel to suppress the entry of outside air into the control panel and preventing the accumulation of oil mist and dust in the control device in the control panel. it can.

It is front sectional drawing of the control board provided with the bag body of embodiment of this invention. It is side surface sectional drawing of the control panel provided with the bag body of embodiment of this invention. It is side surface sectional drawing of the control board provided with the bag body of the bellows structure of embodiment of this invention. It is a figure explaining the pressure valve which exhausts only from the inside of a control panel to an external air direction. It is a figure explaining the means which prevents that the bag body in a control panel is damaged. It is front sectional drawing of the control board provided with the bag body provided with the mechanism which exhausts all the air in a bag body when the door of a control board is opened of embodiment of this invention. FIG. 7 is a top cross-sectional view showing a state in which a door of the control panel shown in FIG. 6 is closed. FIG. 7 is a top cross-sectional view showing a state in which a door of the control panel shown in FIG. 6 is opened.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a front sectional view of a control panel provided with a bag according to an embodiment of the present invention, and FIG. 2 is a side sectional view of a control panel provided with a bag according to an embodiment of the present invention. The control panel 1 includes a housing 11 and a door 12. By closing the door 12, the inside of the control panel 1 can be shielded from the outside of the control panel 1 by the housing 11 and the door 12. A protective cover 43 is attached inside the control panel 1. The control device 31 is fixed to the protective cover 43, and a variable volume bag body 41 is disposed so as to be protected by the protective cover 43.

In order to minimize the pressure change inside the control panel 1 and to make it advantageous in terms of rigidity, the control panel opening 13 is opened on the back surface of the housing 11 of the control panel 1 and the bag body 41 is arranged in the control panel 1. The bag body opening 42 of the bag body 41 communicates the inside of the bag body 41 and the outside of the control panel 1 through the control panel opening 13.
A duct 21 is attached to the back surface of the control panel 1. A cooling fan 33 and a heat sink 32 are attached to the duct 21 in the rear surface of the control panel 1. The heat sink 32 is a member for promoting heat radiation from the control device 31 attached in the control panel 1. The cooling fan 33 can promote heat dissipation from the control device 31 by cooling the heat sink 32.

  The bag body opening portion 42 is provided so that the bag body opening portion 42 is positioned at the lowermost portion of the bag body when the bag body 41 is attached to the housing 11 of the control panel 1. As a result, oil mist and dust that have entered the bag body 41 naturally flow out of the bag body opening 42, and oil mist and dust can be prevented from accumulating inside the bag body 41. The pressure valve 51 is a pressure valve that exhausts only from the inside of the control panel 1 to the outside air direction outside the control panel 1. Although it is attached to the lower part of the housing 11 in FIGS. 1-3, it is not necessarily limited to the lower part.

  The bag body 41 is a flexible bag having a variable volume, and is made of a material having excellent oil resistance such as NBR rubber or nylon, and has a bag-like or bellows-like structure. FIG. 3 is a side cross-sectional view of a control panel provided with a bellows structure bag according to an embodiment of the present invention. The bag body 41 shown in FIG. 3 is a bellows structure bag body.

  When the pressure inside the control panel 1 becomes high, the air inside the control panel 1 expands, and a bag-like (see FIGS. 1 and 2) or bellows (see FIG. 3) bag body 41 is inside the control panel 1. The air inside the bag body 41 is discharged to the outside air outside the control panel 1. As a result, an increase in pressure inside the control panel 1 can be suppressed. When the pressure inside the control panel 1 becomes low, the bag body 41 swells and the outside air is sucked into the bag body 41. Thereby, the pressure difference between the pressure in the space outside the bag body 41 inside the control panel 1 and the outside air pressure outside the control panel 1 can be reduced.

  Here, the case where all the air in the bag body 41 is exhausted is considered. In this case, when the temperature inside the control panel 1 is further increased, the air inside the control panel 1 is thermally expanded, and the air pressure inside the control panel 1 is increased. Then, the housing 11 of the control panel 1 and the wall surface of the door 12 bulge (bend) outward, and a load is applied to the control panel 1. Therefore, as shown in FIGS. 1 to 3, the pressure valve 51 is attached to an arbitrary wall surface of the control panel 1. The pressure valve 51 is attached to the lower part of the housing 11 in FIGS.

  FIG. 4 is a diagram illustrating a pressure valve 51 that exhausts only from the inside of the control panel to the outside air direction. The suction hole 53 side is disposed on the inner side of the control panel 1, and the exhaust hole 57 side is disposed on the outer side of the control panel 1. When a certain pressure or more is applied to the sealing plate 55 from the suction hole 53 side (that is, when the pressure inside the control panel 1 rises and the pressure is more than a certain value), the sealing plate 55 pushes the spring 56, A gap is generated between the O-rings (packings) 54. The air inside the control panel 1 is discharged to the outside of the control panel 1 from the suction hole 53 to the exhaust hole 57 through the generated gap. When pressure is applied from the exhaust hole 57 side, the sealing plate 55 is pressed against the O-ring 54, so that no gap is formed between the sealing plate 55 and the O-ring 54, and air flows from the exhaust hole 57 to the suction hole 53. I will not pass. Further, when the temperature inside the control panel 1 decreases and the pressure decreases, the bag body 41 sucks the outside air outside the control panel 1 so that the pressure between the inside of the control panel 1 and the outside of the control panel 1 is increased. Mitigating the difference.

  By the way, the bag body 41 is a flexible bag having a variable volume, and is made of an oil-resistant material such as NBR rubber or nylon, so that it may be damaged inside the control panel 1. There is. And the possibility that a bag 41 will be damaged when the position of the side surface of the bag of the bag body 1 fluctuates by shrinking or inflating the bag body 41 increases. NBR rubber is a typical special rubber widely used as an oil-resistant rubber called acrylonitrile-butadiene rubber.

  FIG. 5 is a view for explaining means for preventing the bag body in the control panel from being damaged. When there is a possibility that the bag body 41 may be damaged inside the control panel 1, a non-airtight protective cover 43 is attached, or the bag body 41 is arranged in a separate chamber in the control panel 1. Here, the separate chamber may be a small chamber covered with a shielding plate (which has air permeability) that shields the location of the bag body 41 in the control panel 1 and the bag body 41 may be disposed in the small chamber. In the embodiment of FIG. 5, a filter 61 such as an air filter or a wire mesh is attached to the bag body opening 42. The filter 61 does not need to have performance until the oil mist is completely prevented from entering.

  When opening and closing the door 12 of the control panel 1 for maintenance and inspection, depending on how the door 12 is opened and closed, there is a possibility that a large amount of air enters the bag body 41 when the door 12 is closed. . When the pressure inside the control panel 1 rises after the door 12 is closed, there is no problem because the air is exhausted from the bag body 41 or the pressure valve 51. However, when the pressure inside the control panel 1 decreases, there is a possibility that air exceeding the maximum capacity of the bag body 41 must be inhaled in order to reduce the pressure difference between the inside and outside of the control panel 1.

  If there is no air inside the bag body 41 when the door 12 is closed, the maximum volume of air in the bag body 41 can be sucked even if the pressure inside the control panel 1 decreases. Therefore, a mechanism for exhausting all the air inside the bag body 41 when the door 12 is closed is provided. The exhaust mechanism will be described with reference to FIGS. FIG. 6 is a front cross-sectional view of a control panel including a bag body having a mechanism for exhausting all air in the bag body when the door 12 of the control panel 1 is opened. FIG. 7 is a top sectional view showing a state in which the door of the control panel shown in FIG. 6 is closed. FIG. 8 is a cross-sectional top view of the control panel shown in FIG. 6 with the door opened.

  In the state where the door 12 shown in FIG. 7 is closed, the first link bar 75 guided by the guide 76 is pushed down by the inner wall of the door 12. Accordingly, the tip end side of the second link bar 74 supported by the bearing 77 is flipped up. The compression plate 71 is lifted against the spring 73 by jumping up the tip end side of the second link bar 74. By this operation, a space in which the bag body 41 contracts or expands is formed.

  On the other hand, in the state where the door 12 shown in FIG. 8 is open, the second link bar 74 does not receive the force from the first link bar 75 that tries to push up the tip of the second link bar 74, so that the compression plate 71 is pushed down by the spring 73. The air inside the bag body 41 is discharged to the outside air.

  Thus, when the door 12 is opened, the link mechanism (74, 75, 76, 77) becomes free, and the air inside the bag body 41 is discharged to the outside air by the spring 73 and the compression plate 71 of the bag body 41. When the door 12 is closed, a capacity for the bag body 41 to suck in outside air is secured by the link mechanism. Even if the bag shape is a bellows shape, a similar exhaust mechanism can be provided.

  If the bag 41 is damaged, an oil mist sensor 58 (see FIG. 3) is installed inside the control panel 1 and in the vicinity of the bag 41 in order to notify immediately. When the oil mist concentration increases, an alarm is notified. The installation position of the oil mist sensor 58 may be determined in advance in accordance with the shape and material of the bag body 41, and a location that is easily damaged is examined in advance. As the oil mist sensor 58, a known sensor such as a light scattering type sensor or a sensor that detects a change in the frequency of the crystal resonator can be used.

It is difficult to create a completely sealed control panel 1 with an assembly-type control panel 1 composed of a large number of parts used in many machine tools. As described based on the embodiment of the present invention, the present invention is directed to the bag body opening 42 of the bag body 41 from the small gap formed in the wall surface formed by the casing 11 and the door 12 of the control panel 1. However, since the outside air is actively sucked in, the outside air can be sucked in with a small pressure difference, and even if a slight gap is generated in the control panel 1, the entry of oil mist and dust can be prevented. Further, since the liquefied oil does not enter the control panel 1 and the filter 61 is not clogged, it is advantageous in running cost.
Further, in the present invention, when the pressure difference in the control panel cannot be alleviated only by discharging the air in the bag with variable volume, the control panel is provided with a pressure valve capable of exhausting only in the direction from the control panel to the outside of the control panel. Thus, it is possible to solve the problem that the control panel is stressed by the pressure increase in the control panel.

DESCRIPTION OF SYMBOLS 1 Control panel 11 Housing 12 Door 13 Control panel opening 21 Duct 22 Inlet 23 Exhaust outlet 31 Control device 32 Heat sink 33 Cooling fan 41 Bag body 42 Bag body opening 43 Protective cover 51 Pressure valve 52 Pressure valve housing 53 Suction hole 54 O-ring (packing)
55 Sealing plate 56 Spring 57 Exhaust hole 58 Oil mist sensor 61 Filter 71 Compression plate 72 Guide shaft 73 Spring 74 Second link bar 75 First link bar 76 Guide 77 Bearing

Claims (10)

In a control panel having an openable / closable door for shielding a heat-generating control device used in a machine tool disposed inside from the outside,
A variable volume bag body having an opening installed inside the control panel and communicating with the outside of the control panel;
A pressure valve acting only in the direction of releasing the air inside the control panel to the outside of the control panel;
With
The control panel characterized in that the variable volume bag body is adjusted so as to eliminate a pressure difference between the inside and the outside of the control panel by changing the volume of the bag body.   2. The control panel according to claim 1, further comprising a mechanism for exhausting air inside the variable volume bag body to the outside when the door of the control panel is in an open state.   The control panel according to claim 1, further comprising a protective cover that covers the variable volume bag.   The control panel according to any one of claims 1 to 3, wherein the volume-variable bag is installed in a separate room inside the control panel.   The control panel according to any one of claims 1 to 4, wherein a filter for preventing intrusion of chips by cutting into the variable volume bag is provided in the opening.   The control panel according to claim 1, wherein the volume-variable bag body has oil resistance.   The control panel according to claim 1, wherein the volume-variable bag body has a bag shape.   The control panel according to claim 1, wherein the variable volume bag has a bellows shape.   2. When the variable volume bag is disposed inside the control panel, the opening communicating with the outside of the control panel is located at the lowermost part of the variable volume bag. The control board as described in any one of -8.   The control panel according to any one of claims 1 to 9, wherein an oil mist sensor is installed in the vicinity of the inside of the control panel and outside the bag body with the variable volume.

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