JPH0575554B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention utilizes the suction action of vacuum pressure to adsorb and hold thin plates such as semiconductor wafers or fine particles such as plant seeds. This invention relates to vacuum tweezers that can be removed.

(Prior Art) This type of vacuum tweezers has a tweezers main body which opens and closes a flow path by operating a built-in valve mechanism (not shown) by operating a push button 1, for example, as shown in FIG. 2, and a suction section 5 having a flat suction plate 4 at the tip of a suction conduit 3 whose proximal end is slidably attached to one end side of the tweezers main body 1. A connector 8 that is removably screwed into the connecting portion 7 provided on the end side.
The connector 8 is connected to a suction source such as a vacuum pump (not shown) via a suction tube 9 fitted to the connector 8.

As a conventional example of this vacuum tweezers, for example, there is one previously provided by the present applicant in Japanese Patent Application No. 181474/1982, but the internal structure and operation thereof are described in the seventh patent.
This will be explained with reference to FIG.

This vacuum tweezers 10 is configured such that when the push button 11 shown in FIG.
2 receives pressure from the spring 13 from below to open and close the valve chamber 1.
4, and the annular ventilation groove 15 provided on the outer periphery of the middle part of the opening/closing valve body 14 crosses the opening/closing valve chamber 14. Channel 17 and second suction channel 1
8, and the opening/closing valve body 14 blocks communication between the two flow paths 17 and 18, and the air chamber 19 in the opening/closing valve chamber 14 is branched from the air chamber 19 communicating with the first suction flow path 18. The outlet side of the bypass flow path 20 that opens toward the second terminal position side is connected to an on-off valve body 14.
The leak valve is in a position where it is not blocked by the leak valve and is in communication with the leak valve.

Therefore, even if the second suction flow path 18 side is connected to a suction source (not shown), the suction recess 2 of the suction plate 22 that communicates with the first suction flow path 17 via the suction conduit 21
Since no negative pressure is generated in 3, adsorption is not possible and what is already adsorbed is removed.

Next, when the push button 11 is pressed, the on-off valve body 12
is moved under the elastic force of the spring 14 and is at the second end position in the on-off valve chamber 14 as shown in FIG. The two channels are aligned with the channels 17 and 18 and communicate with each other, and the lower end side surface of the moved on-off valve body 12 blocks the outlet side of the bypass channel 20.

Therefore, since the on-off valve side is in communication and the leak valve side is in a closed state, a predetermined negative pressure is generated in the suction recess 23 by the suction of the suction source (not shown), and the suction plate 2
A semiconductor wafer or the like can be adsorbed onto the surface of 2.

The reference numeral 24 in FIGS. 7 and 8 indicates that an operating shaft 25 that supports the on-off valve body 12 at the first end position of the valve chamber 14 and connects the push button 11 and the on-off valve body 12 slides. This is a fixing bush that can be inserted freely, and the fixing bush 24 is mounted in the tweezers body 16 by an E-ring 27 that is fitted in a truncated conical hole 26 whose outer diameter gradually decreases. Further, reference numeral 28 denotes a spherical body rotatably housed in a cap 29 screwed onto the tip of the tweezers main body 16, and is in a spherical state, with the tip side of the spherical body 28 facing the suction plate. The proximal end of the suction conduit 21 screwed into the suction conduit 22 is press-fitted to allow the suction section to be operated freely and to communicate the fluid flow path from the suction recess 23 to the air chamber 19.

(Problems to be Solved by the Invention) However, like the vacuum tweezers having the above-mentioned valve mechanism, the suction flow path is normally blocked and the flow path is opened by operating a push button (normally closed type). ), for example, if the work involves a lot of suction, the push button must be pressed all the time, which is difficult to operate, and if you accidentally let go of the push button, it will suction and cause damage during transportation. There were problems such as dropping the adsorbed object and damaging it.

Therefore, in the present invention, in order to solve the above-mentioned problems, the suction flow path is normally in communication and is in a state where adsorption is possible, and when a push button is pressed, the suction flow path is shut off to separate the adsorbed object. We provide vacuum tweezers of the release type (normally open type), and in the normally open type, suction is performed even when suction work is not required, so there is a risk of wasting suction air or suctioning objects other than the target. Therefore, this problem has been improved by providing a shutoff valve in the suction flow path behind the opening/closing valve, which can shut off the suction when unnecessary. Furthermore, the leak valve improves the residual suction force due to air leakage from the on-off valve at the time of shutoff and the decrease in detachment due to electrostatic action generated in the suction portion.

(Means for Solving the Problems) The gist of the present invention is to consist of a suction part and a tweezers body to which the suction part is attached, and within the said tweezers body there is a channel that communicates with the suction part. 1
and a second suction flow path that communicates with the suction source via a connecting member such as a suction tube, and between the first and second suction flow paths, the suction flow path is perpendicular to the flow path. An on-off valve chamber is provided, and the first and second valves are arranged on the outer periphery of the intermediate portion in this on-off valve chamber.
An on-off valve body having an annular vent that can be aligned with the first and second suction channels is slidably housed, and the annular vent is aligned with the first and second suction channels at one end of the on-off valve body. and the first opening/closing valve chamber where both flow paths communicate with each other.
A first spring means is provided at the terminal end position of the opening/closing valve body for normally biasing the opening/closing valve body, and a first annular vent hole is provided at the other end of the opening/closing valve body and aligned with the biasing force of the spring means.
The on-off valve is configured by providing a pressing means for moving the on-off valve chamber to a second end position where the on-off valve chamber is displaced from the second suction flow path and both flow paths are blocked, and the on-off valve is configured to open and close on the first end position side. The valve chamber communicates with the first suction channel side via a bypass channel and communicates with the atmosphere via a small hole, and during adsorption when the opening/closing valve body is in the first end position, the bypass A leak valve whose flow path and small hole are closed by the on-off valve body is provided in front of the on-off valve, and further behind the on-off valve there is a guide hole orthogonal to the second suction flow path. A shutoff valve body having a small-diameter shaft portion at an intermediate portion is slidably inserted into the guide hole, and an annular flow path is formed between the small-diameter shaft portion and the guide hole. At a position where the part is aligned with the second suction passage, the suction passage is communicated through the annular passage, and at a position where the part is misaligned, the second suction passage is shut off by the shutoff valve body. This vacuum tweezers is equipped with a shutoff valve as described above.

(Example) The present invention will be described below based on an example shown in FIGS. 1 to 5. As shown in FIGS. 1 and 2, the vacuum tweezers are composed of a suction section 30 and a tweezers main body 31, and a connecting section provided at the rear end side of the tweezers main body 31 (on the side opposite to the suction section 30). Although not shown, a connector is screwed onto the 38 side as in the case of FIG. 6, and is connected to an air intake source via a suction tube. Adsorption part 3
0 is composed of a suction plate 32 and a suction conduit 33. The suction plate 32 has a flat suction recess 34 on one surface, and the peripheral edge of the suction recess 34 forms a suction surface 35, and the suction plate 32 has a suction conduit 33. A large number of adsorbed objects such as wafers are adsorbed. Note that the suction plate is used by changing it to one of various shapes depending on the adsorbed material. For example, when adsorbing particulate matter such as plant seeds, it is preferable to form the suction plate in the shape of a nozzle whose diameter gradually decreases. For this purpose, the suction plate 32 is removably attached to the suction conduit 33, and in the conventional example, a screw means is used.
In this embodiment, the structure is press-fitted in order to make the diameter small. Further, the proximal end side of the suction conduit 33 made of a small diameter pipe is press-fitted into a spherical body, which will be described later, provided inside the tweezers body 31.

Next, the tweezers main body 31 includes a central grip part 36 that is provided with various valve structures and is held by hand for operation, a cap 37 that is screwed onto the tip side of the grip part 36, and a cap 37 that is screwed onto the tip side of the grip part 36. The connecting portion 38 is screwed onto the rear end side. The gripping portion 36 includes:
A first suction channel 39 and a second suction channel 40 are bored through the longitudinal axis,
A cylindrical opening/closing valve chamber 41 extending orthogonally is provided between both flow paths, and an air chamber 42 is provided in front of the first suction flow path 39.
2 and the upper side of the on-off valve chamber 41 are the first suction flow path 3
It communicates with the air chamber 9 through a bypass passage 43 branched from an air chamber 42 .

On one end side (the upper end side in the drawing) of the on-off valve chamber 41, the bypass flow path 43 and the on-off valve chamber 4 are connected.
An atmosphere introduction hole 44 for introducing the atmosphere into the first suction flow path 39 side through a part of the first suction flow path 39, and a center hole 45 through which an operating shaft of an on-off valve body to be described later is inserted are bored. There is. Further, on the other end side (lower end side in the drawing) of the on-off valve chamber 41, there is a fitting recess 46 of a larger diameter and an inner side of the on-off valve chamber 41.
A truncated conical hole 47 having a larger diameter and gradually decreasing in diameter toward the outside is provided.

The on-off valve body 48 that is slidably housed in the on-off valve chamber 41 is in the first terminal position when the on-off valve body 48 is in the first terminal position moved most upwardly (the state shown in FIG. 1). and second suction channels 39, 40
An annular ventilation hole 49 on the outer periphery of the middle section to align with the
An operating shaft 50 that is inserted through the central hole 45 and projects out of the grip part 36 is integrally formed on the upper side, and a spring insertion hole 51 is provided on the lower side.
is provided.

The structural members that cooperate with the on-off valve body 48 to form the on-off valve are assembled as shown in FIG. That is, the operating shaft 5 is inserted from the lower side of the on-off valve chamber 41 into the on-off valve body 48 and bored through the central hole 45.
An opening/closing push button 52 is attached to the tip of 0 with a set screw 53, and a cylindrical spring receiver 54 with a flange is attached.
The upper end side of the coil spring 55 whose lower end side is externally fitted into the cylindrical part of is fitted into the spring insertion hole 51 of the on-off valve body 48, and the flange part of the spring receiver 54 is fitted into the fitting recess 46. Then, a C-shaped retaining ring 56 is fitted into the truncated conical hole 47 to lock the spring receiver 54. An air hole 57 is formed in the center of the spring receiver 54 to communicate the lower side of the on-off valve chamber 41 with the atmosphere, so that the on-off valve body 48 is not subjected to air resistance when sliding, and the above-mentioned A small protrusion 58 is vertically provided on the lower surface of the opening/closing push button 52 so that an appropriate gap is provided between the lower surface and the outer wall of the grip part 36 when the opening/closing push button 52 is pressed. The atmosphere is introduced from the atmosphere introduction hole 44 to the air chamber 42 side through the upper side of the on-off valve chamber 41.

Next, an arc-shaped seat surface 59 is formed at the end of the gripping portion 36 adjacent to the air chamber 42, and the seat surface 59 is formed in an arcuate shape.
9 is seated with a spherical body 60 into which the proximal end of the suction conduit 33 is press-fitted, and a hemispherical notch 61 that opens toward the air chamber 42 is provided in the spherical body 60. Press-fitted suction conduit 3
No. 3 through holes 62 communicate with each other. The spherical body 60 is held by the arc-shaped inner surface 63 of the cap 37 screwed onto the gripping part 36, and the spherical body 60
is made rotatable by the arc-shaped inner surface 63 and the seat surface 59, and the direction of the suction portion 30 coupled thereto can be freely changed.

Furthermore, a cutoff valve 64 is provided on the second suction flow path 40 side to appropriately close the flow path. As shown in FIGS. 4 and 5, the cutoff valve 64 includes a cutoff valve body 65 and a guide hole 6 which is passed through the grip portion 36 into which the cutoff valve body 65 is slidably inserted.
It consists of 6. This guide hole 66 is bored so that the sliding direction of the cutoff valve body 65 is 90 degrees different from that of the opening/closing valve body 48 and crosses the second suction flow path 40 at right angles. A flange-shaped cutoff pushbutton 67 is formed at one end, and a small diameter shaft portion 68 is formed at the middle portion in the longitudinal direction.
Reference numeral 8 is provided at a position that aligns with the second suction channel 68 when the seat surface of the cutoff push button 67 comes into contact with the outer surface of the grip part 36, and its outer peripheral area is aligned with the annular channel 69.
is formed. Incidentally, reference numeral 70 is a retaining pin inserted into the distal end side of the shutoff valve body 65 to prevent it from coming off.

Next, the operation of the vacuum tweezers having the above structure will be explained.

When adsorbing an adsorbent, as shown in FIG. 1, the on-off valve side does not press the on-off push button 52;
On the shutoff valve side, operate the shutoff push button 67 to insert the entire shutoff valve body 65 into the guide hole 66 to open the annular flow path 69.
is aligned with the second suction channel 40 (see Fig. 4), and hold the grip part 36 with your hand to remove the suction recess 3.
4 towards the suction part. In this state, the on-off valve body 4
8 is urged upward by the pressure of the coil spring 55 with the spring receiver 54 as a reaction plate, so the opening valve element 48 slides to the first terminal position, which is the uppermost end of the opening/closing valve chamber 41. has been done.

Therefore, the first suction flow path 39 and the second suction flow path 40 are connected to the annular ventilation hole 49 provided in the on-off valve body 48.
and are in communication with each other, and the opening/closing valve chamber 4
The bypass flow path 43 and the small hole 44 which are open to the upper side of the second suction flow path 40 are each blocked by an on-off valve body 48, and the cutoff valve 64 provided in the second suction flow path 40 also closes the annular flow. Since they communicate through the passage 69, a semiconductor wafer or the like can be attracted to the attraction surface 35 of the attraction plate 32 by operating a suction source (not shown).

If you wish to interrupt the suction operation, operate the cut-off push button 67 and pull out a part of the cut-off valve body 65 from the guide hole 66 as shown in FIG. When the flow path 40 and the small diameter shaft portion 68 are brought into a misaligned state, the second suction flow path 40
is closed by the outer circumferential surface of the shutoff valve body 65, so that there is no suction of unneeded adsorbed substances and there is no waste of suction air.

In addition, when the adsorbed object held by suction is to be released after being conveyed to a predetermined location, the opening/closing push button 52 is pressed as shown in FIG. 2, and the opening/closing valve body is 48 Open/close valve chamber 4
7 to the second end position, which is the lowest end.

As a result, the annular ventilation hole 49 that communicated the first suction flow path 39 and the second suction flow path 40 becomes misaligned and is blocked by the outer peripheral surface of the on-off valve body 48. The bypass flow path 43 and the atmosphere introduction hole 44 communicate through the upper side of the on-off valve chamber 47 after the on-off valve body 48 has moved, and the first suction flow path 39
Atmospheric air is introduced into the air chamber 42 and the like.

Therefore, the adsorbed matter that had been suctioned and held on the suction surface 35 is released, but the adsorption part, which is caused by a slight air leak in the opening/closing valve caused by the air introduced from the air introduction hole 44, is removed. This can improve the situation in which detachment is impossible due to residual suction force acting on the 30 side or electrostatic action generated in the suction part, and can promote detachment and fall.

(Effects of the Invention) As is clear from the above-described embodiments, in the vacuum tweezers of the present invention, the on-off valve is always open and adsorption is possible, and the on-off valve is opened by pressing a button only when removing the adsorbed object. Because of the closed configuration, the accident of falling of the suction object due to a button operation error is reduced compared to a conventional configuration in which the suctionable state is maintained by button operation.

In addition, when adsorption work is temporarily interrupted, a shutoff valve is operated to prevent unnecessary suction.
In addition, the leak valve allows for smooth release.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the vacuum tweezers according to the present invention, FIG. 1 is a vertical cross-sectional view of the main parts of the vacuum tweezers in the suction state, and FIG. 2 is a longitudinal cross-sectional view of the main parts of the vacuum tweezers in the detached state. , FIG. 3 is an exploded perspective view showing the structural members of the on-off valve, FIG. 4 is a partial vertical cross-sectional view showing the shut-off valve in the communicating state, FIG. 5 is a partial vertical cross-sectional view showing the shut-off surface in the closed state, and FIG. The figure is an overall plan view with a part cut away of a general vacuum tweezers, Figure 7 is a vertical sectional view of the main part of the conventional vacuum tweezers in the detached state, and Figure 8 is the main part of the conventional vacuum tweezers in the adsorbed state. FIG. [Explanation of symbols], 30... suction part, 31... tweezers body, 32... suction plate, 33... suction conduit, 34... suction recess, 35... suction surface, 36...
...gripping part, 37...cap, 38...connecting part,
39...First suction channel, 40...Second suction channel, 41...Opening/closing valve chamber, 42...Air chamber, 43...
...Bypass flow path, 44...Atmospheric introduction hole, 45...
Central hole, 46... Fitting recess, 47... truncated conical hole, 48... Opening/closing valve body, 49... Annular ventilation hole, 5
0... Operating shaft, 51... Spring insertion hole, 52... Opening/closing push button, 53... Set screw, 54... Spring receiver, 55... Coil spring, 56... Retaining ring, 57
...Air hole, 58...Small protrusion, 59...Seat surface, 6
0... Spherical body, 61... Notch, 62... Through hole,
63... Arc-shaped inner surface, 64... Shutoff valve, 65...
Shutoff valve body, 66... Guide hole, 67... Shutoff push button, 68... Small diameter shaft portion, 69... Annular flow path, 70
...stopping pin.

Claims (1)

[Claims] 1 Consists of a suction part and a forceps body to which the suction part is attached, and inside the forceps body there is a first suction flow path communicating with the suction part side, and an air suction source is connected via a connecting member such as a suction tube. A second suction flow path is provided which communicates with the first and second suction flow paths, and an on-off valve chamber that is orthogonal to the flow path is provided between the first and second suction flow paths. An on-off valve body having an annular vent that can be aligned with the first and second suction channels is slidably housed on the outer periphery, and the annular vent is located at one end of the on-off valve body. A spring means is provided for constantly biasing the on-off valve body to a first end position of the on-off valve chamber where the on-off valve chamber is aligned with the second suction flow path and communicates with the two flow paths, and the other end of the on-off valve body is provided with a spring means. The annular vent in alignment with the biasing of the spring means is displaced from the first and second suction channels to a second end position of the valve chamber where both channels are blocked. A pressing means is provided to constitute an on-off valve, and the on-off valve chamber on the first end position side communicates with the first suction channel side via a bypass channel and communicates with the atmosphere via a small hole. A leak valve is provided in front of the on-off valve so that the on-off valve body closes the bypass passage and the small hole during adsorption when the on-off valve body is in a first end position, Furthermore, a guide hole is provided at the rear of the on-off valve and is orthogonal to the second suction flow path,
A shutoff valve body having a small-diameter shaft portion in the intermediate portion is slidably inserted into the guide hole, and an annular flow path is formed between the small-diameter shaft portion and the guide hole. At a position aligned with the second suction flow path, the second suction flow path is communicated with through the annular flow path, and at a misaligned position, the second suction flow path is shut off by a shutoff valve body. Vacuum tweezers equipped with a shutoff valve.