JP5174418B2 - Vacuum generator - Google Patents

Description

  The present invention is used for a vacuum generating apparatus having a vacuum generating mechanism that operates with compressed air supplied from the outside to be mounted on a component mounting apparatus (mounter) for mounting an electronic component at a specific position on a circuit board. The present invention relates to a vacuum generator capable of preventing foreign matters from entering the vacuum generating mechanism for a long period of time.

  Conventionally, an ejector-type vacuum generating mechanism (simply called an ejector or a vacuum generating mechanism) that generates a vacuum state at a vacuum suction port by introducing compressed air from an air supply port and switching the flow of the compressed air. Known (Patent Document 1), a plurality of components have been used for adsorbing electronic components in a component mounting apparatus.

  Such an ejector has a silencer made of a sintered body in front of the air discharge port in order to reduce the exhaust sound when the compressed air is discharged. And from the viewpoint of maintenance and vacuum performance, an ejector (hereinafter referred to as the former) in which the silencer has a play in the direction of the flow path of the compressed air exhaust, with more emphasis on the silencer function than the filter function, and the filter function. There is an ejector with no play (hereinafter referred to as the latter).

JP 2002-257100 A

  However, in the former ejector, when a vacuum state is generated in the vacuum suction port (referred to as a vacuum is generated), the silencer is exhausted by the compressed air exhausted in the range of play (for example, about 1 mm). It is pushed to the outside and frictionally moves in the arranged flow path. When the vacuum state of the vacuum suction port is released (during vacuum break), an intake operation occurs at the air discharge port, and the silencer is pushed back from the air discharge port in the range of the play. Friction moves in the arranged flow path. That is, if the silencer has been used for many years, the silencer is slid several times in the range of the play, so that the outer shape of the silencer is worn or deformed by friction, and the space of the play is increased. Some have gaps from the beginning to shorten the vacuum break time. If the ejector continues to be used in such a state, the ejector removes dust and metal powder floating in the atmosphere outside the ejector from the space of the increased clearance due to the intake action during the vacuum break. Inhale. And there was a possibility that it may enter into an electromagnetic valve, a poppet valve, etc. which change the compressed air in an ejector, and may cause a malfunction. To solve this problem, the silencer must be replaced. However, when there are a large number of ejectors to be maintained, the work cost and the time taken for the work become enormous.

  On the other hand, in the latter ejector, deformation due to friction of the silencer can be reduced, but in the intake action at the time of vacuum break, dust or metal powder drifting in the atmosphere outside the ejector is sucked into the ejector. There is no change in it. For this reason, the silencer is likely to be clogged at an early stage, and the maintenance cycle of the ejector is shortened.

  The present invention has been made to solve the above-described conventional problems. Even when the ejector is used for a long period of time, foreign matters such as dust and metal powder floating in the atmosphere outside the ejector can enter the inside of the ejector. It is an object of the present invention to provide a vacuum generator capable of preventing inhalation and extending the maintenance cycle of an ejector.

The invention according to claim 1 of the present application includes an air supply port for introducing compressed air, a switching means for switching the flow of the compressed air, a vacuum suction port for guiding a vacuum state generated by the switching means, and the vacuum state. A vacuum generating mechanism comprising: an air discharge port through which compressed air is discharged, and a silent unit that is provided in a front stage of the air discharge port and reduces exhaust noise when the compressed air is discharged ( a vacuum generating mechanism) of the ejector, said compressing and filtering member which is detachably disposed in the flow path of the compressed air after passing through the silent section, the filter member is a the filtration member and the separate air The present invention solves the above-mentioned problems by having a detachable filter member holding means that is brought into close contact with the discharge port.

  According to the present invention, an ejector (an ejector-type vacuum) is provided by a filtration member disposed in a flow path of compressed air after passing through the silent means and a filtration member holding means for bringing the filtration member into close contact with the air discharge port. Since foreign matter such as dust and metal powder drifting in the atmosphere outside the generation mechanism) always passes through the filtering member without being directly sucked into the silent means at the time of vacuum break, Foreign matter can be captured. For this reason, even if the ejector is used for a long time in the vacuum generator, it is possible to prevent foreign matters such as dust and metal powder floating in the atmosphere outside the ejector from being sucked into the ejector.

  Further, since the filtering member is arranged at the subsequent stage of the silent means, the filtering member can be replaced without disassembling the silent means, and it is not necessary to frequently replace the silent means, thus extending the maintenance cycle. be able to. Furthermore, since the filtration member can be easily removed and cleaned, the filtration member can be easily reused.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  An embodiment of the present invention will be described with reference to FIGS. 1 is an exploded perspective view of the vacuum generator according to an embodiment of the present invention with the upper case removed, FIG. 2 is an exploded perspective view of the periphery of the filtration member of the vacuum generator, and FIG. 3 is a schematic configuration diagram of the vacuum generator. 4 is an air circuit diagram of the vacuum generator, FIG. 5 is an exploded perspective view of the periphery of the ejector of the vacuum generator, and FIG. 6 is a schematic sectional view of the vicinity of the filter member of the vacuum generator.

  Initially, the whole structure is demonstrated using FIG.1 and FIG.2.

  The vacuum generator 100 includes, for example, an ejector 110, a filtering member 134 disposed outside the ejector 110, a pressing member 142 that holds the filtering member 134, a lower case 146, and an upper case 148. The ejector 110 is attached to the lower case 146 with a bolt 110 a via a fixed plate 140. The lower case 146 is provided with a filtration member attachment hole 146a that allows the filtration member 134 to be attached and detached from the outside of the lower case 146. The upper case 148 is attached to cover the upper surface of the ejector 110.

  Next, each component will be described in detail.

  For example, as shown in FIG. 1, the ejector 110 is a four-unit assembly in which four independent ejector-type vacuum generating mechanisms are assembled. As shown in FIG. 3, the ejector 110 includes a manifold 111, electromagnetic valves 114 and 116 provided on the manifold 111, and a vacuum sensor 128.

  The manifold 111 includes, for example, poppet valves 118 and 120, a control valve 122, a silencer 124 as a silencer, and an internal filter 130 shown in FIG. 4 (see FIG. 6). An air supply port 112 for introducing compressed air and a vacuum suction port 132 for guiding the vacuum state generated inside the manifold 110 to the outside are provided on the front surface (the right side in FIG. 3) on the outside of the manifold 111. Each has an air discharge port 126 through which compressed air is discharged in order to create a vacuum state on the left side of FIG.

  The electromagnetic valve 114 is, for example, an electromagnetic valve that controls generation of vacuum, and the electromagnetic valve 116 is, for example, an electromagnetic valve that controls vacuum break. Each controls the poppet valves 118 and 120 provided in the manifold 111 and functions as a means for switching the flow path. That is, the electromagnetic valves 114 and 116 and the poppet valves 118 and 120 are switching means for switching the flow of the introduced compressed air. When the solenoid valve 114 is opened, the poppet valve 118 is opened, and the compressed air passes through the poppet valve 118. When the solenoid valve 116 is opened, the poppet valve 120 is opened, and the compressed air passes through the poppet valve 120.

  The control valve 122 is, for example, a valve for generating a vacuum state when compressed air passes, and has an optimal shape based on the flow of compressed air, the shape of its flow path, and the shape of the silencer 124. Can do.

  The silencer 124 is provided, for example, in the front stage of the air discharge port 126 and has a silent function for reducing exhaust sound when compressed air is discharged and a filter function for filtering foreign matter. That is, there is a trade-off relationship that the filter function is lowered if the silent function is improved, or the silent function is lowered if the filter function is improved. In this embodiment, since the filter member 134 is used in the subsequent stage of the silencer 124, the filter function can be lowered. For this reason, the silent function can be improved, and the silencer 124 can be made of a porous sintered body having a coarser mesh than usual. That is, the pressure loss of the compressed air in the silencer 124 can be reduced, and a vacuum state with a high degree of vacuum can be easily generated. As shown in FIG. 1, the silencer 124 can be replaced or cleaned by removing the bracket 136 attached to the manifold 111 with the bolt 136a.

  In the present embodiment, the air outlet 126 is provided in the bracket 136. As shown in FIG. 1, the bracket 136 is individually provided for the four ejector-type vacuum generating mechanisms in the same manner as the silencer 124.

  The vacuum sensor 128 is a sensor that measures a vacuum state generated in the manifold 111, for example.

  The internal filter 130 blocks foreign matter sucked from the vacuum suction port.

  As shown in FIG. 4, the filtering member 134 is disposed in the flow path of the compressed air after passing through the silencer 124 that is a silent means. The filtering member 134 is made of, for example, a resin that is rich in elasticity, and has excellent cushioning properties. The compression rate of the filter member 134 can be, for example, from several percent to several tens of percent. As shown in FIG. 5, the filtering member 134 has a notch 134 a at a portion where the bolt 144 that locks the pressing member 142 is inserted and removed. For the filtering member 134, for example, porous polyurethane can be used as a material, and a material having a thickness d of about 10 mm can be used. The roughness of the eyes is several tens of μm or less, preferably about 5 μm. And since the filtration member 134 is an open cell structure from which the cell membrane of the hole has been removed, even if it is compressed, the pressure loss of the compressed air passing therethrough can be reduced. Moreover, the filter member 134 is excellent in water resistance. Therefore, it can be easily washed with water or a neutral detergent.

  As shown in FIG. 5, the fixing plate 140 has an engaging portion 140a and an ejector mounting portion 140b. The engaging portion 140a is bent at a right angle with respect to the ejector mounting portion 140b. The engaging portion 140 a is provided for attaching the pressing member 142 with the bolt 144. The ejector mounting portion 140b is provided to be fastened to the lower case 146 together with the ejector 110 by the bolt 110a.

  The pressing member 142 is a member (filtering member holding means) for bringing the filtering member 134 into close contact with the air outlet 126, and includes a locking part 142a, a filtering member holding part 142b, and a filtering member compression part 142c. . The locking portion 142a is a tip portion bent perpendicularly to the filtering member holding portion 142b, and has an L shape as shown in FIGS. As shown in FIG. 6, the L-shaped tip of the locking portion 142 a is inserted into the inside of the filtration member mounting hole 146 a provided in the lower case 146.

  The filter member holding part 142b has a large number of holes. The hole has an opening at least on the axis of the air discharge port 126 in order to minimize the pressure loss of the compressed air discharged from the air discharge port 126 provided in the ejector 110. And the filtration member holding | maintenance part 142b has a hole in which the volt | bolt 144 is loosely fitted. Through this hole, the pressing member 142 is attached to the engaging portion 140 a of the fixing plate 140 by a bolt 144.

  The filtration member compression portion 142c is a tip portion bent vertically from the filtration member holding portion 142b, and is an end portion of the pressing member 142 at a symmetrical position of the locking portion 142a. The length of the filtration member compression part 142c is D shorter than the thickness d of the filtration member 134. Therefore, when the pressing member 142 is attached to the fixing plate 140 with the distance D by the bolt 144, the filtering member 134 is compressed. Then, the filter member 134 is brought into close contact with the air outlet 126 provided in the bracket 136. At the same time, due to the restoring force of the filter member 134, the tip of the engaging portion 142a of the pressing member 142 inserted inside the filter member mounting hole 146a of the lower case 146 is pressed and fastened. That is, the filtering member 134 is brought into close contact with the air discharge port 126 from the outside by attaching the pressing member 142. For example, two hexagon bolts can be used as the bolt 144.

  Next, the operation of this embodiment will be described using the air circuit diagram of this embodiment shown in FIG.

  First, a case where a vacuum is generated at the vacuum suction port 132 will be described. The compressed air introduced from the air supply port 112 opens the poppet valve 118 when the electromagnetic valve 114 is opened with the electromagnetic valve 116 closed. The compressed air introduced from the air supply port 112 passes through the poppet valve 118, passes through the control valve 122, the silencer 124, and the filter member 134, and is discharged to the outside of the vacuum generator 100. At this time, in the flow path from the vacuum suction port 132 to the control valve 122, a vacuum is generated by the action of the control valve 122. The vacuum state is guided to the vacuum suction port 132. When foreign matter is sucked from the vacuum suction hole port 132, it is removed by the internal filter 130. The vacuum state at this time can be measured by the vacuum sensor 128.

  Therefore, a suction pad is piped to the vacuum suction port 132, and the workpiece is sucked to the suction pad by bringing the suction pad into the vacuum state, so that the workpiece can be transported or fixed.

  Next, the vacuum break of the vacuum suction port 132 will be described. This is performed when the workpiece adsorbed in a vacuum state is released. The electromagnetic valve 114 is closed to block the compressed air introduced from the air supply port 112. At this time, since the flow path from the control valve 122 to the vacuum suction port 132 and further to the workpiece is in a vacuum state, suction force is generated in the flow path of the control valve 122, the silencer 124, and the filter member 134, and the vacuum generator 100. Air is sucked from the outside. Thereby, since the vacuum state is released and the atmospheric pressure is reached, the work is released from the suction pad. In addition, since the filter member 134 is provided at the outermost part of the vacuum generator 100, the silencer in the vacuum generator 100 even if dust or metal powder drifts in the atmosphere outside the vacuum generator 100. No foreign matter adheres to 124.

  That is, as shown in FIG. 6, the ejector has the filter member 134 disposed in the flow path of the compressed air after passing through the silencer 124, and the pressing member 142 that brings the filter member 134 into close contact with the air outlet 126. Since foreign matters such as dust and metal powder floating in the atmosphere outside 110 are not directly sucked into the silencer 124 when the vacuum breaks, they always pass through the filter member 134. Can catch foreign objects. Further, since the filter member 134 is disposed at the subsequent stage of the silencer 124, the filter member 134 can be easily replaced without disassembling the silencer 124, and a maintenance cycle for replacing or cleaning the silencer 124. Can be lengthened.

  In this way, in the vacuum generator 100, even if the ejector 110 used in the present embodiment is used for a long period of time, foreign matter such as dust or metal powder floating in the atmosphere outside the ejector 110 is ejected. Inhalation can be prevented. Further, it is not necessary to frequently replace the silencer 124, and the maintenance cycle can be lengthened. Furthermore, since the filtration member 134 can be removed and cleaned, the filtration member 134 can be easily reused.

  Furthermore, since the filtration member 134 is provided with the notch portion 134a, the filtration member 134 is not caught by the bolt 144, and the pressing member 142 can be easily attached and detached with the bolt 144. Further, the front end of the locking portion 142 a of the pressing member 142 is fixed inside the filtration member mounting hole 146 a of the lower case 146, and the filtration member 134 is brought into close contact with the air discharge port 126 with only two bolts 144. Therefore, the attachment / detachment of the filter member 134 can be performed very easily. That is, it is excellent in maintenance workability.

  Further, the pressing member 142 has an opening at least on the axis of the air discharge port 126, the silencer 124 can be made rougher than usual, and the filtering member 134 has an open cell structure. As a result, the pressure loss at the silencer 124 can be minimized by preventing the pressure loss from increasing even if compressed, and the pressure loss of the compressed air discharged from the air discharge port 126 provided in the ejector 110 can be reduced. The vacuum generated in the ejector 110 can be minimized, and the vacuum can be made highly efficient and in a high vacuum state.

  In addition, the length D of the filtration member compression portion 142 c is shorter than the thickness d of the filtration member 134. Therefore, when the pressing member 142 is attached to the fixing plate 140 with the bolt 144 by the distance D, the filtering member 134 is compressed, so that the filtering member 134 can be easily brought into close contact with the air outlet 126 provided in the bracket 136. . Further, the distance D is the length of the filtration holding member compression portion 142c and can be stably reproduced even when the filtration member 134 is replaced. Therefore, the pressure loss due to the filtration member 134 can be kept constant, and the ejector 110 The degree of vacuum generated can be generated stably.

  In the present embodiment, the filtering member 134 is provided outside the bracket 136 of the ejector 110, but the present invention is not limited to this. For example, the filtering member 134 may be disposed between the silencer 124 and the bracket 136, and the bracket 136 itself may be used as the filtering member holding means. In that case, the vacuum generator 100 can be made smaller. However, in the present embodiment, the filter member 134 is provided outside the bracket 136 of the ejector 110, and the pressure member 142, which is one, is removed, so that each of the air exhausts provided in the four ejector-type vacuum generating mechanisms. Since the filter member 134 outside the outlet 126 can be replaced at a time, the maintenance workability is further improved.

  Further, in this embodiment, the pressing member 142 has four or five holes as shown in FIGS. 1 and 5, but the present invention is not limited to this. For example, you may comprise with the metal mesh from which the whole surface of the press member 142 becomes an opening.

  Further, the fixing plate 140 is not necessarily required. Obviously, if the ejector 110 has a hole or the like to which the pressing member 142 can be attached, it can be used. In addition, if the filtering member 134 is disposed inside the bracket 136, it is clear that the pressing member 142 is not necessary.

  In the present embodiment, the ejector type vacuum generation mechanism having four ejectors is used as the ejector 110, but the present invention is not limited to this. For example, it is obvious that the present invention can be applied with one or more ejector-type vacuum generating mechanisms.

  Further, in the present embodiment, the silencer 124 is one in which the silencer function is prioritized and the filter function is reduced, but is not limited thereto. For example, the present invention has the effect even if it is a silencer 124 with a filter with an enhanced filter function. By bringing the filter member 134 of the present invention into close contact with the outside of the ejector 110, foreign matter adsorbed on the filter portion of the silencer 124 provided inside the ejector 110 is reduced, and the effort for disassembling the ejector 110 can be reduced. This is because the maintenance cycle can be lengthened.

  In the present embodiment, the filtering member 134 is made of polyurethane, but is not limited thereto. It is an elastic porous resin. Desirably, the fineness and thickness of the eyes can be designed and used as long as they can be washed with water or a neutral detergent. Although the thickness d is about 10 mm, it is not limited to this.

The disassembled perspective view of the state which removed the upper case of the vacuum generator which is embodiment of this invention Similarly, an exploded perspective view around the filtration member of the vacuum generator Similarly schematic diagram of vacuum generator Air circuit diagram of vacuum generator Similarly, an exploded perspective view around the ejector of the vacuum generator Similarly, a schematic cross-sectional view of the vicinity of the filtration member of the vacuum generator

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Vacuum generator 110 ... Ejector (Ejector type vacuum generation mechanism)
110a, 136a, 144 ... bolt 111 ... manifold 112 ... air supply port 114, 116 ... solenoid valve 124 ... silencer 126 ... air discharge port 132 ... vacuum suction port 134 ... filtration member 134a ... notch 136 ... bracket 140 ... fixed Plate 140a ... engaging portion 140b ... ejector mounting portion 142 ... pressing member 142a ... locking portion 142b ... filtration member holding portion 142c ... filtration member compression portion 146 ... lower case 146a ... filtration member mounting hole 148 ... upper case

Claims (1)

An air supply port for introducing compressed air, a switching means for switching the flow of the compressed air, a vacuum suction port for introducing a vacuum state generated by the switching means, and compressed air for discharging the vacuum state A vacuum generating mechanism comprising: an air discharge port; and a silent unit that is provided in a front stage of the air discharge port and that reduces exhaust noise when the compressed air is discharged;
A filtration member that is detachably disposed in the flow path of the compressed air after passing through the silent means;
Filtrate and over member and the separate and are removable filter member holding means is brought into close contact with the air discharge opening by compressing the filtering member,
A vacuum generator characterized by comprising:

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