JP2009039821A - Fixture and sensor fixing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel fixing method and a fixture therefor, performing firm attachment to a base while performing easy detachment without enlarging an area and a space required for attachment. <P>SOLUTION: This fixture 50 fixes objects 21, 30 having a through-hole 32 to the base 25 attracting a magnet. The fixture includes: a head portion 51 which has an adjusting screw hole, is larger than the through-hole 32, and does not pass through the through-hole; and an adjusting member having a screw portion 53 screwed in the adjusting screw hole of the head portion 51 and a magnet portion 52 provided at its end. With the head portion 51 brought into contact with the objects 21, 30, the adjusting member that adjusted a positional relationship with the head portion 51 to prevent the magnet portion 52 from being brought into contact with the base 25, is inserted into the through-hole of the object. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fixture for fixing an object having a screwing through hole to a base that attracts a magnet, such as a metal base, and in particular, a sensor whose attachment position such as an AE sensor or a vibration sensor greatly affects a detection signal. The present invention relates to a fixing tool to be fixed and a fixing method of a sensor.

  In various processing apparatuses, various sensors such as an AE sensor and a vibration sensor are used to detect a contact state between a tool (grinding stone, tool, end mill, etc.) and a workpiece. In such a sensor, the mounting position greatly affects the detection signal. Hereinafter, the AE sensor will be described as an example. However, the present invention is not limited to this, and can be applied to fixing any other sensor or object having a through hole.

  In processing equipment, detection of contact between the tool (grindstone) and workpiece (air cut), detection of dressing completion of the tool (grindstone) by the dressing tool (dresser), detection of contact of the tool (grindstone) with a predetermined reference pin For example, the AE sensor is used for positioning the tool by detecting and detecting a collision between the tool (grinding stone) and the other part of the processing apparatus. An AE sensor detects an acoustic signal propagating in a solid, and there are various methods depending on a target frequency, but an AE sensor used in a processing apparatus such as a grinding machine has several tens of kHz to several Targeting a 100 MHz ultrasonic region, it is composed of piezoelectric elements.

  FIG. 1 is a diagram illustrating an example of use of an AE sensor, and is a diagram illustrating a configuration in which an AE sensor is provided in a processing system including a grinding machine. In the following description, the case where the AE sensor is applied to the configuration as shown in FIG. 1 is taken as an example. In FIG. 1, a mechanism for holding and rotating a workpiece W and a moving base 12 are provided on a base 11. The moving base 12 is provided with a grindstone rotating mechanism 13 that rotates the grindstone 14. The grinding machine is controlled by a processing machine control device 15. In addition, when the grindstone 14 is replaced with a new one or used for a certain period of time, a process called a dressing process is performed in order to make the surface of the grindstone 14 suitable for grinding. In this process, the surface of the grindstone 14 is treated by bringing a dresser into contact with the rotating grindstone 14. The above part is the same as the processing system including a normal grinding machine.

  An AE (Acoustic Emission) sensor 21 is attached to the housing of the grindstone rotating mechanism 13, and an AE wave generated by the grindstone 14 is transmitted to the AE sensor 21 through the housing of the grindstone rotating mechanism 13, and the AE sensor 21 transmits an AE signal. appear. The AE signal processing device 22 processes the AE signal, detects that the grindstone 14 has contacted the workpiece W, and notifies the processing machine control device 15 of it. The use of the AE sensor in the processing apparatus is described in Patent Document 1 and the like, and is widely known, so further explanation is omitted.

  If the fixing of the AE sensor 21 to the casing is loose, there arises a problem that the vibration of the casing is not sufficiently transmitted to the AE sensor 21. Therefore, the AE sensor 21 needs to be firmly fixed to the housing.

  FIG. 2 is a diagram showing a conventional method for fixing the AE sensor 21 to the housing (base) 25.

  2A, a through hole for screwing is provided in a part 30 of the AE sensor 21, a screw hole is provided in the base 25, and the screw 31 is screwed into the screw hole of the base 25 through the through hole of the AE sensor 21. This is fixed to the base 25. This fixing method has the advantage that it can be firmly fixed and the AE sensor 21 can be reused by removing the screw 31, but it is necessary to provide a screw hole in the base 25. Therefore, the fixing method of FIG. 2A is suitable for permanent fixing.

  In FIG. 2B, an adhesive 32 is applied to the mounting surface of the AE sensor 21 and adhered to the base 25. As this adhesive, an instantaneous adhesive is often used. This fixing method requires that the mounting surface of the base 25 be clean to some extent because the adhesive cannot be used if the mounting surface of the base 25 is dirty with oil or the like. Further, the adhesive itself may contaminate the surface of the base 25, and if the surface of the base 25 is coated, the coating film may be damaged. Further, the mounting surface of the AE sensor 21 may be contaminated or damaged by the adhesive. If the adhesive to be used is an instantaneous adhesive, the AE sensor 21 can be removed from the base 25 by applying an impact to the bonded portion. However, if the impact is applied, the AE sensor 21 may be damaged. For this reason, the fixing method of FIG. 2B is also suitable for permanent fixing.

  The AE signal generated by the AE sensor 21 varies greatly depending on the mounting position of the AE sensor 21. Therefore, when fixing the AE sensor, it is necessary to find and fix a position where optimum detection can be performed. For this reason, the AE sensor mounting position is changed and fixed at a position where a large AE signal can be obtained. However, even if the optimum position is searched, the AE signal must be fixed firmly at each position. Since the strength cannot be accurately evaluated, it is necessary to firmly fix the AE sensor.

  The fixing method as shown in FIGS. 2A and 2B is not suitable for searching for the attachment position of the AE sensor for the above reason, and cannot be used.

  Usually, since the base to which the AE sensor is attached is made of metal and the magnet is adsorbed, a method of using a magnet has been conventionally used as a fixing method of the AE sensor. As a fixing method using a magnet, there are a method in which a magnet is sandwiched between an AE sensor and a base, and a method in which a part of a jig (fixing tool) that presses the AE sensor against the base is used as a magnet and is attracted to the base. The method of sandwiching the magnet has a problem that the AE signal is attenuated because the magnet is interposed between the base and the AE sensor.

  FIG. 2C shows a conventional fixing method using a fixing tool partially made of a magnet. The AE sensor 21 has a through hole for screwing in a part 30. As shown in the figure, the side tube 42 that supports the upper plate 41 is made a magnet and can be attracted to the base 25. A spring 43 is provided on the upper plate 41, and the spring 43 presses and fixes the AE sensor 21 to the base 25. If the strong magnet 42 is used, the AE sensor 21 can be firmly fixed to the base 25, and can be removed from the base 25 and reused.

JP-A-6-114692

  As shown in FIG. 2C, the fixing method of the conventional example using a fixing tool having a magnet uses a fixing tool that covers the AE sensor 21, so that the fixing tool has a larger size than the AE sensor, There was a problem that the installation location was limited. In particular, an AE sensor having a screw-through hole for finally fixing with a screw requires a portion 30 provided with a screw-fastening hole, and the fixing tool is large including the portion 30, so the size is considerably large. There was a problem of getting bigger.

  The present invention has been made in view of such problems, and can be easily removed without increasing the area and space required for attaching an object such as a sensor, but can be firmly attached to a base. It aims to realize a new fixing method and a fixing tool necessary for it.

  The present invention is directed to mounting an object having a through hole for screwing on a base that attracts a magnet. In order to achieve the above object, the fixing method of the present invention is applied to a head portion having a size that does not pass through the through hole. An adjustment screw hole is provided, and the screw portion of the adjustment member having a magnet portion at the tip is aligned with the adjustment screw hole, and the length below the head portion is adjusted and inserted into the through hole. If the magnet part at the tip does not contact the base, the force that the magnet part attracts to the base is transmitted to the head part, and the head part presses and fixes the object to the base.

  That is, the fixture of the present invention is a fixture that fixes an object having a through hole to a base that attracts a magnet, has an adjustment screw hole, and is larger than the through hole and does not pass through the through hole. An adjustment member having a head portion and a screw portion screwed into the adjustment screw hole of the head portion and a magnet portion provided at a tip thereof, and the magnet is in a state where the head portion is in contact with the object. The adjusting member, whose positional relationship with the head portion is adjusted so that the portion does not contact the base, is inserted into the through hole of the object.

  The fixing method of the present invention is a fixing method for fixing a sensor having a through hole to a base that attracts a magnet, and has an adjustment screw hole, which is larger than the through hole and does not pass through the through hole. Using a fixture comprising: a head portion having an adjustment screw hole; and an adjustment member having a screw portion screwed into the adjustment screw hole of the head portion and a magnet portion provided at a tip thereof, and the head portion The adjustment member, whose positional relationship with the head portion is adjusted so that the magnet portion does not come into contact with the base in a state where is in contact with the object, is inserted into the through hole of the object.

  As the magnet is closer to the base, the attraction force increases. According to the present invention, the magnet portion at the tip of the adjustment member of the fixture inserted into the through hole of the object can be adjusted to a position very close to the base without contacting the base, so that it is strongly attracted to the base. . As a result, the suction force is also transmitted to the adjusting member and the head portion, and the head portion presses the object against the base. Moreover, since a magnet is used, removal is easy.

  In the fixture of the present invention, the length from the head portion to the tip of the lower adjustment member can be freely adjusted by adjusting the relative positions of the adjustment screw hole of the head portion and the screw portion of the adjustment member. It is possible to cope with various thicknesses of the through-hole portion of the object, and the attractive force by the magnet portion can be adjusted. Further, since the through hole of the object is used, it can be attached if the object can be installed.

  According to the present invention, since it is easy to remove and can be fixed to any part as long as the object can be installed, it can be fixed to a place where it has been difficult to install.

  Therefore, if the present invention is applied to an AE sensor or the like, an optimum fixing position can be determined after temporarily fixing it to a place where the measurement conditions seem to be better and conducting a test. Since the fixed position can be determined in this way, it is possible to find out the behavior of a new AE signal that has been overlooked so far and perform analysis and control.

  FIG. 3A is an external view of a fixture (jig) according to the embodiment of the present invention. As shown in FIG. 3A, the fixture 50 of the embodiment is provided at a head portion 51 having an adjustment screw hole, a screw portion 53 to be screwed into the adjustment screw hole of the head portion 51, and a tip. And an adjustment member having a magnet portion 52. A knob 54 is provided on the side of the adjustment member opposite to the magnet portion 52 to further rotate the screw portion 53.

  FIG. 3B shows a state in which the fixture 50 is inserted into the screwing through hole 32 provided in the portion 30 of the AE sensor 21, and FIG. 3C shows the inserted state.

  As shown in FIG. 3C, in the inserted state, it is necessary that the tip of the magnet portion 52 is not in contact with the metal base 25 that adsorbs the magnet. If they are in contact, the head portion 51 does not press the portion 30 of the AE sensor 21, and the AE sensor 21 cannot be fixed to the metal base 25. Therefore, first, the knob 54 of the adjustment member is rotated with respect to the head 51 to adjust the position of the screw portion 53 with respect to the head portion 51, and in the insertion state shown in FIG. The position is adjusted so as not to contact the metal base 25. The closer the tip of the magnet portion 52 is to the metal base 25, the stronger the attracting force by the magnet portion 52 and the stronger the force for fixing the AE sensor 21, so the position of the screw portion 53 relative to the head portion 51 is adjusted as appropriate.

  After the above adjustment, as shown in FIG. 3B, the tip of the magnet portion 52 is inserted into the screwing through hole 32 provided in the portion 30 of the AE sensor 21 installed on the metal base 25. . As a result, the state of FIG. 3C is obtained, the magnet portion 52 is attracted to the metal base, and the head portion 51 presses the portion 30 of the AE sensor 21 against the metal base 25, so that the AE sensor 21 is fixed.

  FIG. 3D shows a state where the AE sensor 21 is fixed to the metal base 25. As shown in the drawing, two fixing tools are inserted into two through holes provided in the portion 30 of the AE sensor 21, and the AE sensor 21 is fixed to the metal base 25.

  Although the embodiment of the present invention has been described above, it goes without saying that various modifications are possible. For example, when the portion 30 provided with the through hole of the AE sensor 21 is made of a material that does not attract a magnet, for example, the fixing tool can be easily inserted.

  Further, the metal base 25 may be any material as long as the material is attracted by the magnet.

  The present invention can be applied to any case where an object having a through hole is fixed to a base to which a magnet is attracted, but is temporarily fixed to determine a fixing position of a sensor such as an AE sensor. It is especially effective when applied to.

FIG. 1 is a diagram illustrating a configuration example of a machining system in which an AE sensor is used. It is a figure explaining the conventional fixing method of an AE sensor. It is a figure which shows embodiment which fixes an AE sensor with the fixing method of this invention.

Explanation of symbols

21 AE sensor (object)
25 Base 32 Through-hole 51 Head part 52 Magnet part 53 Screw part

Claims (2)

A fixture for fixing an object having a through hole to a base that attracts a magnet,
A head portion having an adjustment screw hole, which is larger than the through hole and does not pass through the through hole;
An adjustment member having a screw part screwed into the adjustment screw hole of the head part and a magnet part provided at the tip;
The adjustment member that has adjusted the positional relationship with the head unit so that the magnet unit does not contact the base in a state where the head unit is in contact with the object is inserted into the through hole of the object. Fixture featured. A fixing method for fixing a sensor having a through hole to a base that attracts a magnet,
An adjustment having an adjustment screw hole, a head portion that is larger than the through hole and does not pass through the through hole, a screw portion screwed into the adjustment screw hole of the head portion, and a magnet portion provided at the tip And a fixture comprising a member,
In the state where the head portion is in contact with the object, the adjusting member whose positional relationship with the head portion is adjusted so that the magnet portion does not contact the base is inserted into the through hole of the object. Sensor fixing method.

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