JP5655017B2 - Work suction and fixing device and ultrasonic inspection system - Google Patents

Description

  The present invention relates to a workpiece adsorption and fixing device and an ultrasonic inspection system that adsorb and fix a workpiece such as a semiconductor material in a state of being immersed in water in a water tank.

For example, a technique for inspecting a workpiece such as a semiconductor material using ultrasonic waves is known. The applicant of the present application is a technique for inspecting defects such as voids and cracks in the workpiece based on the elapsed time from transmission to reception while receiving the reflected wave while transmitting ultrasonic waves to the workpiece. (Refer to Patent Document 1).
According to Patent Document 1, it is possible to easily perform a defect inspection of a workpiece.

JP 2004-212191 A

  In Patent Document 1, when a workpiece is inspected for defects, the workpiece is sucked and fixed to the suction pad using a water pressure difference generated by sucking water through the suction pad in a state where the workpiece is immersed in water in the water tank. ing. This is because if the position of the workpiece fluctuates during the inspection, the inspection result includes an error.

  However, in Patent Document 1, an attempt is made to adsorb and fix a work to the suction pad using a water pressure difference generated by sucking the water in the water tank through the suction pad while the flexible work is immersed in the water in the water tank. For example, when the peripheral edge of the workpiece is warped in a direction away from the suction pad, a gap is generated between the peripheral edge of the workpiece and the suction pad. Then, the water pressure difference generated by sucking the water in the water tank through the suction pad becomes small. With this small water pressure difference, there is a possibility that the peripheral portion of the work cannot be attracted to the suction pad and the suction fixed state cannot be maintained. In this regard, Patent Document 1 does not mention the above-described problem that may occur when inspection is performed on a workpiece having flexibility.

  The present invention has been made in view of the above circumstances, and even if the workpiece is flexible, the workpiece can be stably maintained in an adsorbed and fixed state while the workpiece is immersed in water in a water tank. An object of the present invention is to provide an adsorption fixing device and an ultrasonic inspection system.

In order to achieve the above object, a workpiece suction and fixing device according to the present invention is a workpiece suction and fixing device that suctions and fixes a workpiece in a state where the workpiece is immersed in water in a water tank, the suction port for sucking water in the water tank and the above A discharge port for discharging the sucked-in water, a circulation channel for circulating water in the water tank from the suction port to the discharge port, a water supply unit provided in the circulation channel for circulating the water, a base, and A plurality of suction cups having a lip portion and adsorbing the workpiece, wherein the base portion has a through-hole communicating with the suction port at a substantially center, and the lip portion having elasticity passes through the through-hole. When the water is sucked in, the inner space of the lip portion is narrowed to adsorb the workpiece, and the circulating water channel is connected to the suction port when the water pressure on the suction port side with respect to the water supply unit falls below a predetermined value. Side of And most important, further comprising a pressure regulating valve for performing the opening adjusted to increase the water pressure.

  According to the workpiece adsorption / fixation device of the present invention, even if the workpiece has flexibility, the adsorption / fixation state can be stably maintained in a state where the workpiece is immersed in water in the water tank.

It is a schematic block diagram of the workpiece | work adsorption | suction fixing device and ultrasonic inspection system concerning embodiment of this invention. It is a figure showing the outline | summary of the workpiece | work adsorption | suction fixing device which concerns on embodiment of this invention. It is a principal part expanded sectional view showing the mounting structure of the suction cup which is one component of the workpiece | work adsorption | suction fixing device which concerns on embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a workpiece suction fixing device and an ultrasonic inspection system according to embodiments of the present invention will be described in detail with reference to the drawings.

[Outline of Work Suction Fixing Device and Ultrasonic Inspection System According to Embodiment of the Present Invention]
First, the outline | summary of the workpiece | work adsorption | suction fixing device and ultrasonic inspection system which concern on embodiment of this invention is demonstrated.
In the prior art according to Patent Document 1, the work is adsorbed and fixed to the suction pad using a water pressure difference generated by sucking the water in the water tank through the suction pad while the flexible work is immersed in the water in the water tank. When trying to do so, for example, when the peripheral edge of the workpiece is warped away from the suction pad, a gap is formed between the peripheral edge of the workpiece and the suction pad. Then, the water pressure difference generated by sucking the water in the water tank through the suction pad is reduced, and with this small water pressure difference, there is a possibility that the peripheral edge of the work cannot be attracted to the suction pad and the suction fixed state cannot be maintained. .
Therefore, in the workpiece suction fixing device and the ultrasonic inspection system according to the embodiment of the present invention, the suction cup has a base portion and a lip portion and sucks the workpiece, and the base portion is substantially centered on the through hole communicating with the suction port. The elastic lip has a suction cup that adsorbs the workpiece by narrowing the inner space of the lip when the water in the water tank is sucked through the through hole. Even if it has the property, it was decided to maintain a stable adsorbed and fixed state in a state where the work was immersed in water in the water tank.

[Schematic Configuration of Work Suction Fixing and Fixing Device 11 and Ultrasonic Inspection System 13 According to an Embodiment of the Present Invention]
Next, schematic configurations of the workpiece suction and fixing device 11 and the ultrasonic inspection system 13 according to the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram of a workpiece suction and fixing device 11 and an ultrasonic inspection system 13 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an outline of the work suction fixing device 11 according to the embodiment of the present invention. FIG. 3 is an enlarged cross-sectional view of a main part showing a mounting structure of a suction cup 33 that is one component of the workpiece suction and fixing device 11 according to the embodiment of the present invention.

The difference between the workpiece adsorption / fixing device 11 and the ultrasonic inspection system 13 is as follows. That is, the ultrasonic inspection system 13 is obtained by adding the configuration of the ultrasonic probe 15 for performing the defect inspection of the workpiece WK to the configuration of the workpiece suction and fixing device 11. The ultrasonic probe 15 has a function of performing a defect inspection of the workpiece WK by scanning along the arrow direction in FIG.
Therefore, in the following description, the workpiece adsorption / fixing device 11 according to the embodiment of the present invention will be described to replace the description of the ultrasonic inspection system 13.

  As shown in FIG. 1, the workpiece suction and fixing device 11 according to the embodiment of the present invention has a function of maintaining the suction and fixing state of the workpiece WK with respect to the holding member 19 while the workpiece WK is immersed in the water WT of the water tank 17. Have In order to realize the function of maintaining the suction and fixing state, the workpiece suction and fixing device 11 according to the embodiment of the present invention includes a circulating water channel 21 and a water supply pump 23 that functions as a water supply unit of the present invention, as shown in FIG. And a holding member 19, a chamber portion 25, a pressure adjusting valve 27, and a plurality of suction cups 33 having a base portion 29 and a lip portion 31 (see FIG. 3) for adsorbing the workpiece WK.

  The work WK is, for example, a semiconductor material or a semiconductor component. In the present embodiment, for example, a work WK having flexibility is assumed.

  As shown in FIG. 1, the circulation channel 21 has a suction port 21 a that sucks the water WT of the water tank 17 and a discharge port 21 b that discharges the sucked water. The circulation channel 21 has a function as a circulation channel of the water WT of the water tank 17 that discharges the water WT of the water tank 17 sucked from the suction port 21 a from the discharge port 21 b and returns it to the water tank 17.

  A water pump 23 is provided in the middle of the circulation water channel 21 as shown in FIG. The water supply pump 23 has a function of circulating the water WT by sending out the water WT in the water tank 17. Moreover, the circulating water channel 21 has a pressure regulating valve 27 that opens when the water pressure on the suction port 21a side with respect to the water pump 23 falls below a predetermined value.

  When the water pressure on the suction port 21a side with respect to the water supply pump 23 falls below a predetermined value, the pressure regulating valve 27 has a deformation amount due to the adsorption and fixing of the workpiece WK that occurs when the workpiece WK is inspected exceeds an allowable value, or Considering that the load of the water pump 23 may exceed the allowable value, adjust the opening of the pressure adjustment valve 27 according to the water pressure (for example, when the water pressure on the suction port 21a side is slightly below a predetermined value, The opening degree of the regulating valve 27 is adjusted to be small on the open side, and when the water pressure on the suction port 21a side is significantly below a predetermined value, the opening degree of the pressure regulating valve 27 is adjusted to be largely open side).

Here, the predetermined value of the water pressure described above may be appropriately set as the larger one of these allowable values based on the deformation allowable value related to the work WK or the load allowable value related to the water pump 23. . Thereby, the pressure regulating valve 27 functions to prevent excessive deformation of the work WK and overload of the water pump 23 by working so as to increase the water pressure on the suction port 21a side with respect to the water pump 23. Have.

  As shown in FIG. 1, the holding member 19 has a flat contact surface 19 a that contacts the workpiece WK, and has a function of holding the posture of the workpiece WK in a horizontal state. The box-shaped holding member 19 is fixed in a horizontal state with respect to the water tank 17 via a support member (not shown). This is because the positioning of the holding member 19 that holds the posture of the workpiece WK is an important element for increasing the inspection accuracy of defects such as voids and cracks in the workpiece WK.

  As shown in FIGS. 1 and 3, a plurality of receiving holes 35 are formed in the contact surface 19 a of the holding member 19. Each of the plurality of receiving hole portions 35 is formed in a substantially cylindrical shape. A plurality of suction cups 33 are respectively accommodated in the plurality of accommodation holes 35.

  A hollow chamber portion 25 is provided below the plurality of receiving hole portions 35 in the holding member 19. Between each of the plurality of receiving hole portions 35 and the chamber portion 25, a through hole 37 is provided to communicate and connect them. The chamber part 25 is provided in the holding member 19 so as to constitute a part of the circulation water channel 21. The chamber portion 25 having a larger cross-sectional area of the water flow path than the circulation water path 21 sucks the water WT in the water tank 17 through the plurality of suction ports 21a and the plurality of through holes 41, as will be described later. Moreover, it has the function which substantially equalizes the attraction | suction force of the water WT of the water tank 17 between the some suction inlets 21a.

  As shown in FIG. 3, the suction cup 33 formed of an elastic body such as rubber has a base portion 29 and a lip portion 31. A cylindrical insertion hole 39 is provided at the center of the base 29 in the suction cup 33. A bolt 43 opened around the through hole 41 is inserted into the insertion hole 39. The base portion 29 of the suction cup 33 is screwed into the screw hole 43 a formed in the shaft portion of the bolt 43 and the screw groove 37 a formed in the through hole 37, so that the base hole 29 of the suction cup 33 is engaged with the receiving hole portion 35 of the holding member 19. It is attached.

  As shown in FIG. 3, the lip portion 31 of the suction cup 33 extends obliquely upward from the periphery of the base portion 29. A circumferential outer peripheral edge portion (corresponding to a “peripheral edge portion” of the present invention) 31 a of the lip portion 31 is positioned so as to be substantially flush with the contact surface 19 a of the holding member 19. That is, the outer peripheral edge portion 31 a of the lip portion 31 comes into contact with the work WK while the work WK is in contact with the contact surface 19 a of the holding member 19.

  In short, the plurality of suction cups 33 includes the holding member 19 such that the lip portion 31 faces the workpiece WK and the outer peripheral edge portion 31a of the lip portion 31 is substantially flush with the contact surface 19a of the holding member 19. The receiving holes 35 are provided respectively. As a result, the elastic lip portion 31 attracts the workpiece WK by narrowing the inner space S of the lip portion 31 by sucking the water WT of the water tank 17 through the through hole 41 formed in the bolt 43. Is configured to do.

  The plurality of suction cups 33 are arranged such that a pair of suction cups 33 adjacent to each other with a center line extending in the longitudinal direction of the holding member 19 face each other. If the longitudinal direction of the holding member 19 is the row direction and the direction perpendicular to the longitudinal direction is the column direction, in the present embodiment, the plurality of suction cups 33 are provided in alignment with the holding member 19 in 2 rows and 7 columns. It has been.

[Operation of Workpiece Suction Fixing Device 11 According to an Embodiment of the Present Invention]
Next, operation | movement of the workpiece | work adsorption | suction fixing device 11 which concerns on embodiment of this invention is demonstrated.
In the present embodiment, as an example of the workpiece WK, description will be made assuming a glass epoxy substrate having a thickness t of 0.5 mm, for example. Further, it is assumed that the peripheral portion of the workpiece WK is warped in a direction away from the contact surface 19 a of the holding member 19.

  First, the operator turns on a power switch (not shown) of the water pump 23. The water supply pump 23 operates to circulate the water WT by sending out the water WT in the water tank 17 with a preset driving force. Thereby, the preparation for adsorbing and fixing the workpiece WK to the contact surface 19a of the holding member 19 is completed.

  Next, the operator presses the work WK lightly by hand (may be automated) against the contact surface 19a of the holding member 19 that is fixed in a horizontal state with respect to the water tank 17. . Then, due to the suction force of the water WT in the water tank 17 generated at the suction port 21a, the central portion and the peripheral portion of the work WK are drawn so as to be in close contact with the contact surface 19a of the holding member 19.

  Specifically, the elastic lip portion 31 works to suck the work WK by narrowing the inner space S of the lip portion 31 by sucking the water WT of the water tank 17 through the through hole 41. . Even if a force is applied in the direction away from the contact surface 19a of the holding member 19 at the peripheral edge of the workpiece WK, the elastic lip portion 31 works so as to maintain the suction and fixing state with respect to the workpiece WK.

  Therefore, according to the workpiece suction fixing device 11 according to the embodiment of the present invention, even when the peripheral edge portion of the flexible workpiece WK is warped in the direction away from the contact surface 19a of the holding member 19. In the state where the work WK is immersed in the water WT of the water tank 17, the adsorption and fixing state can be stably maintained.

  If the large work WK is positioned so as to cover the entire contact surface 19a of the holding member 19, the water pressure on the side of the suction port 21a with respect to the water pump 23 falls below a predetermined value. Then, the pressure regulating valve 27 operates so as to open a valve body (not shown), assuming that the load of the water pump 23 may exceed the allowable value.

  Therefore, according to the workpiece suction fixing device 11 according to the embodiment of the present invention, even if the large-sized workpiece WK is positioned so as to cover the entire contact surface 19a of the holding member 19, the pressure Since the regulating valve 27 works to increase the water pressure on the side of the suction port 21a with respect to the water pump 23, it is possible to prevent an overload of the water pump 23 in advance.

  Moreover, according to the workpiece | work adsorption | suction fixing device 11 which concerns on embodiment of this invention, the holding member 19 is connected to the some suction inlet 21a and the some through-hole 41, respectively, and the chamber which comprises a part of circulation water channel 21 is comprised. Since it has the portion 25, when sucking the water WT of the water tank 17 through the plurality of suction ports 21a and the plurality of through holes 41, respectively, regardless of the size of the work WK covering the contact surface 19a of the holding member 19 The suction force of the water WT in the water tank 17 between the plurality of suction ports 21a can be substantially equalized.

  By the way, in realizing the workpiece suction fixing device 11 according to the embodiment of the present invention, how to obtain the required suction force P of the single suction cup 33 becomes a problem. This is because if the required suction force P of the single suction cup 33 can be grasped, the driving force of the water supply pump 23 can be set based on the obtained information. Therefore, the concept for obtaining the required suction force P of the single suction cup 33 will be described below.

Now, the suction force of a single suction cup 33 to hold flat warpage of the peripheral portion of the work WK (the attraction of water WT aquarium 17) and P _0. Further, the suction force of a single suction cup 33 movement of the workpiece WK can be suppressed to P ₁ relative to the abutment surface 19a of the holding member 19. Then, at the time of the defect inspection of the work WK may over the workpiece WK, the minimum suction force per single sucker 33 (water pressure) and P _2.
Then, the required suction | attraction force P of the single suction cup 33 can be represented by following formula (1).
P ₀ + P ₁ ≦ P ≦ P ₂ Formula (1)

The suction forces P ₀ , P ₁ , P ₂ of the single suction cup 33 described above vary according to the specifications of the work WK and the suction cup 33. Therefore, the adsorption forces P ₀ , P ₁ , and P ₂ of the single suction cup 33 may be obtained by experiments, simulations, or a combination thereof. The required suction force P of the single suction cup 33 can be obtained by substituting the suction powers P ₀ , P ₁ , P ₂ of the single suction cup 33 thus obtained into the formula (1).

[Operation and Effect of the Work Adsorption / Fixing Device 11 According to the Embodiment of the Present Invention]
According to the work adsorption fixing device 11 according to the embodiment of the present invention, the base 29 is provided with a plurality of suction cups 33 having a base 29 and a lip part 31 for adsorbing the work WK, and the base 29 is a through hole 41 communicating with the suction port 21a. Since the lip portion 31 having elasticity at the center and having elasticity is attracted to the WK work by narrowing the inner space S of the lip portion 31 by sucking the water WT of the water tank 17 through the through-hole 41, Even when the work WK has flexibility and the peripheral edge of the work WK is warped in the direction away from the contact surface 19a of the holding member 19, the work WK is used as the water WT in the water tank 17. The adsorbed and fixed state can be stably maintained in the immersed state.

  Moreover, according to the workpiece | work adsorption | suction fixing device 11 which concerns on embodiment of this invention, it further has the holding member 19 which has the flat contact surface 31a contact | abutted to the workpiece | work WK, and hold | maintains the attitude | position of the workpiece | work WK. The suction cup 33 of the holding member 19 is such that the lip portion 31 faces the workpiece WK and the outer peripheral edge portion 31a on the workpiece WK side of the lip portion 31 is substantially flush with the contact surface 19a of the holding member 19. Therefore, in addition to the above-described effects, the workpiece WK can be accurately maintained in a horizontal suction fixed state.

  Moreover, according to the workpiece | work adsorption | suction fixing device 11 which concerns on embodiment of this invention, the circulating water channel 21 has the chamber part 25, and the through-hole 41 connected to the suction inlet 21a of the base 29 which each of the some suction cup 33 has is the Since it is configured to communicate with the chamber portion 25, the contact surface 19a of the holding member 19 is covered when the water WT in the water tank 17 is sucked through the plurality of suction ports 21a and the plurality of through holes 41, respectively. Regardless of the size of the workpiece WK, the suction force of the water WT in the water tank 17 between the plurality of suction ports 21a can be substantially equalized.

  Moreover, according to the workpiece | work adsorption | suction fixing device 11 which concerns on embodiment of this invention, since the circulating water channel 21 has the pressure adjustment valve 27 opened when the water pressure by the side of the suction inlet 21a with respect to the water supply pump 23 falls below a predetermined value, Even if the large-sized workpiece WK is positioned so as to cover the entire contact surface 19 a of the holding member 19, the pressure adjustment valve 27 increases the water pressure on the suction port 21 a side with respect to the water supply pump 23. Therefore, overloading of the water pump 23 can be prevented in advance.

  And the ultrasonic inspection system 13 which concerns on embodiment of this invention is the ultrasonic probe for performing the defect inspection using an ultrasonic wave for the workpiece | work WK attracted and fixed in the state immersed in the water WT of the water tank 17. The premise is that the child 15 is provided. The ultrasonic inspection system 13 according to the embodiment of the present invention includes a plurality of suction cups 33 each having a base 29 and a lip portion 31 for sucking the work WK, and the base 29 substantially includes a through hole 41 communicating with the suction port 21a. The lip portion 31 having elasticity at the center adsorbs the WK work by narrowing the inner space S of the lip portion 31 by sucking the water WT of the water tank 17 through the through hole 41. In addition, a holding member 19 is provided that has a flat contact surface 31a that contacts the workpiece WK and holds the posture of the workpiece WK. The plurality of suction cups 33 have a holding member such that the lip portion 31 faces the workpiece WK and the outer peripheral edge portion 31a on the workpiece WK side of the lip portion 31 is substantially flush with the contact surface 19a of the holding member 19. 19 respectively.

According to the ultrasonic inspection system 13 according to the embodiment of the present invention, even when the peripheral portion of the flexible workpiece WK is warped in the direction away from the contact surface 19a of the holding member 19, With the WK immersed in the water WT of the water tank 17, the workpiece WK can be accurately maintained in a horizontal and stable adsorption fixed state.
Therefore, according to the ultrasonic inspection system 13 according to the embodiment of the present invention, the defect inspection of the work WK can be performed with high accuracy.

[Other Embodiments]
The embodiment described above shows an example of realization according to the present invention. Therefore, the technical scope of the present invention should not be limitedly interpreted by these. It is because this invention can be implemented with various forms, without deviating from the summary or main features.

  For example, in the present embodiment, the workpiece WK has been described assuming that the peripheral edge thereof is warped in a direction away from the contact surface 19a of the holding member 19, but the present invention is not limited to this example. The workpiece WK to which the present invention can be applied may be a workpiece WK having any shape, such as a workpiece whose central portion has a convex shape or a concave shape with respect to the contact surface 19a of the holding member 19.

  In the present embodiment, the suction cup 33 is disposed with respect to the holding member 19 such that a pair of suction cups 33 adjacent to each other with a center line extending along the longitudinal direction of the holding member 19 face each other. Although described above, the present invention is not limited to this example. You may employ | adopt the aspect which arrange | positions the suction cup 33 with respect to the holding member 19, and a pair of suction cups 33 mutually adjacent | abutted across the centerline extended along the longitudinal direction of the holding member 19. FIG.

  Further, in the present embodiment, an example in which the plurality of suction cups 33 are arranged in 2 rows and 7 columns with respect to the holding member 19 has been described, but the present invention is not limited to this example. The number of suction cups 33 provided in the holding member 19 in the row direction or the column direction and the total number of suction cups 33 can be appropriately set according to the size of the target work WK and the size of the holding member 19.

  In the present embodiment, as an example of the workpiece WK, for example, a glass epoxy substrate having a thickness t of 0.5 mm has been described as an example. However, the present invention is not limited to this example. As the workpiece WK that can be used in the present invention, for example, in addition to a flexible workpiece, a workpiece having unevenness on the suction surface or a combination of a plurality of workpieces having different sizes is used as appropriate. be able to.

DESCRIPTION OF SYMBOLS 11 Work adsorption | suction fixing device 13 Ultrasonic inspection system 15 Ultrasonic probe 17 Water tank 19 Holding member 19a Contact surface 21 Circulating water channel 21a Suction port 21b Discharge port 23 Water supply pump (water supply part)
25 Chamber part 27 Pressure regulating valve 29 Base part 31 Lip part 31a Outer peripheral edge part (peripheral part)
33 Suction cup 35 Accommodating hole portion 37 Through hole 37a Screw groove 39 Insertion hole portion 41 Through hole 43 Bolt 43a Screw portion WK Work WT Water in water tank S Inner space of lip portion

Claims (5)

A work adsorption fixing device that adsorbs and fixes a work immersed in water in a water tank,
A suction port for sucking water in the water tank and a discharge port for discharging the sucked water, and a circulation channel for circulating water in the water tank from the suction port to the discharge port;
A water supply section provided in the circulation channel for circulating the water;
A plurality of suction cups having a base and a lip and adsorbing the workpiece;
With
The base has a through hole that communicates with the suction port at a substantially center.
The lip portion having elasticity adsorbs the workpiece by narrowing an inner space of the lip portion by sucking the water through the through hole ,
The circulating water channel further includes a pressure adjustment valve that adjusts an opening degree so as to increase the water pressure on the suction port side when the water pressure on the suction port side with respect to the water supply portion falls below a predetermined value. Adsorption fixing device. The workpiece adsorption / fixation device according to claim 1,
The predetermined value is set on the basis of a deformation amount allowable value related to the workpiece or a load allowable value related to the water supply unit.
A workpiece adsorbing and fixing device characterized by that. It is a workpiece adsorption fixing device according to claim 1 or 2,
A holding member for holding a posture of the workpiece having a flat contact surface that contacts the workpiece;
The plurality of suction cups include the holding member such that the lip portion faces the workpiece, and a peripheral portion on the workpiece side of the lip portion is substantially flush with the contact surface of the holding member. Provided in each
A workpiece adsorbing and fixing device characterized by that. It is a workpiece adsorption fixing device according to claim 1 or 2,
The circulation channel has a chamber part,
The through-hole communicating with the suction port of the base portion each of the plurality of suction cups is configured to communicate with the chamber portion.
A workpiece adsorbing and fixing device characterized by that. An ultrasonic inspection system that performs ultrasonic defect inspection on a workpiece that is adsorbed and fixed in a state of being immersed in water in a water tank,
A suction port for sucking water in the water tank and a discharge port for discharging the sucked water, and a circulation channel for circulating water in the water tank from the suction port to the discharge port;
A water supply section provided in the circulation channel for circulating the water;
A holding member for holding a posture of the workpiece having a flat contact surface that contacts the workpiece;
A suction cup having a base portion and a lip portion for adsorbing the workpiece;
With
The base has a through hole that communicates with the suction port at a substantially center.
The lip portion having elasticity adsorbs the workpiece by narrowing an inner space of the lip portion by sucking the water through the through hole,
A plurality of suction cups, the lip portion faces the workpiece, and, as the peripheral portion of the workpiece side in the lip portion becomes substantially flush with against the abutment surface of the holding member, the holding member each provided et al are in,
The circulation water channel further includes a pressure adjusting valve that adjusts an opening degree so as to increase a water pressure on the suction port side when a water pressure on the suction port side with respect to the water supply unit falls below a predetermined value. Sonographic system.

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