JP5818197B2 - Tank drilling device - Google Patents

Description

  The present invention relates to a tank drilling device for forming holes for attaching various parts such as gauges and sensors to a tank, particularly a vehicle fuel tank.

  When forming holes for attaching various parts such as gauges and sensors to tanks, especially fuel tanks for vehicles, to prevent the cut pieces from falling into the tank and becoming dirty, It is necessary to take out the outside of the tank, and the production efficiency of the tank is deteriorated by the work of taking out the cut pieces.

As a tank drilling device capable of taking out a cut piece at the end of the cutting operation, for example, a tank drilling device shown in Patent Document 1 is known. The tank drilling device attaches a cutter blade to a drill unit that opens holes for mounting various parts at predetermined locations of a tank, with a predetermined distance from the spindle as a center of rotation, and at the lower part of the spindle, a spindle A piston that moves up and down along the axis of the piston, a piston rod fixed to the lower portion of the piston, and a plurality of arms that are pivoted downward and equally spaced so as to surround the piston rod. A protrusion is provided on the inner side in the vicinity of the attachment portion, and a lower end portion of the arm is provided on the outer side to form a claw. Further, a cam groove is provided in the piston rod so that the protrusion of the arm is connected to the cam. An expansion mechanism is provided that engages with the groove and the protrusion of the arm is pushed up or down by the vertical movement of the piston so that the lower end of the arm is contracted or expanded. A cutter that inserts and expands an expansion mechanism portion into a lower hole opened at a predetermined position of the shaft, expands the expansion mechanism portion, supports the lower surface portion of the lower hole, and rotates integrally with the spindle. The blade is brought into contact with the surface of the tank to open a hole having a predetermined diameter, and the cutting piece cut out by the cutter blade is held by the expansion mechanism.

  In the expansion mechanism of the tank drilling device described above, a cylinder composed of a piston and a piston rod is provided as a member for expanding or reducing the diameter of the arm that supports the lower surface of the through hole, and is loosely fitted to the spindle. The compressed air pipe is used to supply compressed air.

However, in the above punching device, the structure of the expansion mechanism portion becomes complicated and large, so that the hole can be formed only in a tank in which a through hole having a certain size is formed. That is, in order to form a small-diameter hole in the tank, the through-hole also has a small diameter depending on the hole to be formed, but the enlarged expansion mechanism portion cannot be inserted into the small-diameter through-hole, and thus is desired. The size of the hole could not be formed.

In addition, the air pipe of the expansion mechanism portion needs to be configured to be loosely fitted to the spindle and not to rotate when the spindle rotates. For this reason, the expansion mechanism portion of the hole punching device is inserted into the through hole of the tank and penetrated, and then the arm is expanded to contact the lower surface portion of the through hole to give rotational resistance. The air pipe does not rotate even if the spindle is rotated to execute the drilling operation.

Therefore, prior to forming the hole in the tank, an operation for inserting the expansion mechanism portion into the through hole and an operation for operating the expansion mechanism portion to expand the arm and abut the lower surface portion respectively. It was necessary to perform the drilling operation immediately after insertion, and the work efficiency was poor.

Further, the arm supports the lower surface of the pilot hole when the hole is opened by the rotating cutter blade to prevent the cut piece from falling into the tank, but particularly at the end of cutting, the outer periphery of the cut piece is thin. The strength is weakened. If cutting is continued in this state, there is a problem that the cutter blade acts irregularly on the outer periphery of the cut piece and the hole cannot be formed with high accuracy and the cutter blade is easily broken.

Japanese Patent No. 3618693

  The problem to be solved is that the expansion mechanism part of the conventional tank drilling device requires an operating member such as a cylinder for expanding the arm diameter, so that the expansion mechanism part becomes complicated and large. Therefore, it is difficult to form a small-diameter hole. Further, when the hole is formed by the rotating cutter blade, it is necessary to prevent the expansion mechanism portion from rotating with respect to the spindle of the drill unit. It must be supported by the part, and it takes time to form the hole, and the working efficiency is poor. Furthermore, at the end of cutting, the outer periphery of the cutting piece becomes thin and the strength is weakened, and the cutter blade acts irregularly on the outer periphery of the cutting piece, so that the hole cannot be formed with high accuracy and the cutter blade is easily broken. It is in the point.

According to the present invention, a tank drill is formed by rotating a cutting blade provided at a required distance in the direction orthogonal to the axis from the axis of a spindle to be rotated to form a hole in a tank component mounting portion. In the apparatus, the base end portion of the spindle is pivotally supported with respect to the shaft end portion of the spindle, a shaft body provided with a cam surface at the tip end portion, and a predetermined stroke in the axial direction with respect to the shaft body. A small-diameter shaft portion with an outer diameter that can be inserted into a through-hole that is movable and is prevented from rotating and that is inserted in advance in a component mounting portion, and a large-diameter shaft portion with an outer diameter that contacts the periphery of the through-hole. And a holder in which at least two receiving gaps each having an axial length extending over the large-diameter shaft portion and the small-diameter shaft portion are formed. base end is rotatably supported so as to be pivotal at the inner, including the cam surface A holding arm engageable with the lower surface of the through hole periphery by more swings the holding portion provided at a front end portion to the diameter direction sliding contact against the outer peripheral surface of the body, is inserted into the shaft member, the holder A slide disc supported so as to be movable in the axial direction while being secured to the shaft provided on the shaft, and provided on the slide disc so as to be movable in the direction orthogonal to the axis, and attached by the elastic force of the first elastic member. The engaging claw portion that is urged and engageable with the engaged recess provided in the shaft body, and is provided in the holder, and is engaged with the engagement of the shaft body in the shaft hole. The engaging claw engaged with the mating recess is moved in the disengagement direction against the elastic force of the first elastic member to release the engagement, and the slide disc is moved in the axial direction relative to the shaft body. via a disengaging cam that allows the locking slides board missing on the support shaft relative to the shaft member And a tensile elastic member for urging to move the holder proximally, when forming a hole in the component mounting unit by the cutting blade is rotated, the small-diameter shaft into the through hole of the component mounting portion When the shaft body is moved in the insertion direction with the large-diameter shaft portion in contact with the upper surface of the peripheral edge of the through hole and the movement of the holder is restricted, the shaft body is slidably contacted with the outer peripheral surface including the cam of the shaft body. The holding arm that swings in the diameter-enlarging direction moves the holding portion protruding from the accommodation gap to the lower surface of the peripheral edge of the through hole so that it can be engaged, and the engagement releasing cam is covered with the movement of the shaft relative to the holder. Abutting on the engaging claw engaged with the engaging recess, moves in the disengagement direction against the elastic force of the first elastic member to release the engagement, and is prevented from coming off by the elastic force of the tensile elastic member. The holder is moved to the base end side of the shaft body through the slide plate and the shaft in the shaft hole is moved. While maintaining the body entry state, each holding arm is held in a swinging state in which the holding portion protrudes from the accommodation gap, while a hole is formed in the component attachment portion due to the progress of cutting by the rotating cutting blade In this case, the holder arm that moves to the base end side of the shaft body by the elastic force of the tension elastic member holds the swinging state of the holding arm, and the lower edge of the through hole in the cut piece separated from the component mounting portion. The main feature is that it is possible to restrict the cutting piece from falling off the holder by maintaining the engagement state of the holding portion .

  According to the present invention, without providing an operating member such as a cylinder, the support arm can be expanded in diameter by being inserted into the pilot hole so that the cut piece can be held, and the structure can be simplified and miniaturized. . Further, when the hole is formed by the rotating cutting blade, it is possible to avoid holding the cut piece by the support arm having an enlarged diameter and dropping it into the tank. At the end of cutting, the portion to be cut can be prevented from becoming unstable, and the hole can be formed with high accuracy.

It is a fragmentary perspective view which shows the components attachment part of the tank in which a hole is formed with a tank drilling apparatus. It is a whole perspective view of a tank drilling device. It is a center longitudinal cross-sectional view of a tank drilling apparatus. It is sectional explanatory drawing which shows the state which inserted the holder of the tank drilling apparatus in the through-hole. It is sectional explanatory drawing which shows the engagement cancellation | release action of the engagement nail | claw part by a lock release cam. It is sectional explanatory drawing which shows the tank drilling apparatus at the time of a cutting | disconnection. It is sectional explanatory drawing which shows the holding state of the cut piece at the time of completion | finish of a cutting | disconnection. It is sectional explanatory drawing which shows the removal state of a cut piece from a tank drilling apparatus.

When forming a hole in the component mounting portion with the rotating cutting blade, the small diameter shaft portion is inserted into the through hole of the component mounting portion, and the large diameter shaft portion is brought into contact with the upper peripheral surface of the through hole to move the holder. When the shaft body is moved in the insertion direction in a restricted state, the holding arm that slides in contact with the outer peripheral surface including the cam of the shaft body swings in the diameter increasing direction, and the holding portion that protrudes from the accommodation gap is formed in the through hole. The first elastic member is elastically engaged with the engagement claw portion engaged with the engaged recess as the shaft moves with respect to the holder. The holder is moved to the disengagement direction against the disengagement to release the engagement, and the holder is moved to the base end side of the shaft body through the slide disc that is prevented from being pulled out by the elastic force of the pulling elastic member. Each holding arm is maintained while the shaft body enters the holding state, and the holding portion protrudes from the accommodation gap. While being held in a moving state, when a hole is formed in the component mounting part due to the progress of cutting by the rotating cutting blade, it is held by a holder that moves to the base end side of the shaft body by the elastic force of the tensile elastic member Maintaining the above-mentioned swinging state of the arm and maintaining the engagement state of the holding portion with the peripheral edge of the lower surface of the through hole in the cut piece separated from the component mounting portion, it is possible to restrict the cut piece from falling off the holder. the best embodiment to.

The present invention will be described below with reference to the drawings showing examples.
First, the vehicle fuel tank 5 as a tank in which holes are formed by the tank drilling device 1 according to the present invention will be described. As shown in FIG. 1, the vehicle fuel tank 5 is formed by laminating a plurality of different synthetic resin sheets. It is made of synthetic resin that is bonded or laminated, and on its upper surface, a number of parts mounting portions 3 that are attached to the vehicle fuel tank 5 and that correspond to various parts such as gauges, various sensors, and fuel pumps are integrated. It is formed.

  The component mounting portion 3 is formed as a cylindrical portion 3c having a required outer diameter and height, a male screw 3a being turned on the outer peripheral surface, and an upper surface being closed by an upper surface plate 3b. A recess 3e is formed in the central portion of the upper surface plate 3b at a required depth, and a through hole 3d having an inner diameter into which a small-diameter shaft portion 25a of a holder 25 described later can be inserted is formed in the central portion. The opening 7 as a hole is formed by cutting the top plate 3b along the inner peripheral surface of the cylindrical portion 3c.

  As shown in FIGS. 2 and 3, the tank punching device 1 for forming the opening 7 in the upper surface plate 3b is, for example, an arm of an industrial robot that is controlled to move in at least a three-dimensional direction (both not shown). An opening 7 is automatically formed in the component mounting portion 3 by being attached to the tip portion and controlling the movement of the arm.

  A spindle 9 is rotatably supported on a main body (not shown) of the tank drilling device 1, and a rotary shaft of an electric motor 11 provided on the main body is drivingly connected to the spindle 9. The spindle 9 is rotated at a required number of rotations by driving the electric motor 11.

  A rotating body 13 is fixed to the spindle 9, and the rotating body 13 is provided with a blade attachment arm 15 that extends in the radial direction with the spindle 9 as a rotation center. A cutting blade 17 having a cutting edge that extends downward in the drawing and coincides with the axis of the spindle 9 is attached to the tip of the blade mounting arm 15.

  A balancer member 13a is attached to the rotating body 13 on the side opposite to the blade mounting arm 15 and is adjusted so that the weight on the side opposite to the blade mounting arm 15 side coincides with the spindle 9 as a center.

  A shaft portion 19 a of a coupled rotating body 19 having an axis line coinciding with the spindle 9 is rotatably supported via a bearing 21 at the central portion of the rotating body 13. As the bearing 21, an angular bearing that receives loads in both the thrust direction and the radial direction is suitable.

A base end portion of a shaft body 23 extending in the axial direction with a required axial length is fixed to the lower portion of the connecting rotary body 19, and a distal end portion (lower end side in the drawing) of the shaft body 23 faces the tip end. As a result, a cam surface 23a having a gradually smaller diameter is formed. Further, a long hole 23b extending in the axial direction is formed in the axial direction intermediate portion of the shaft body 23. The long hole 23b is set to an axial length corresponding to the amount of movement of the holder 25 described later relative to the shaft body 23 in the axial direction. Further, an engaged recess 23c is formed on the outer peripheral surface of the shaft body 23 corresponding to the lower portion of the long hole 23b.

The shaft body 23 is inserted and supported so as to slide in the axial direction with respect to the shaft hole 25 c of the holder 25. The holder 25 is formed integrally with the outer diameter large diameter shaft portion 25b that can be inserted into the recess 3e and can contact the bottom surface of the through hole 3d and the lower portion of the large diameter shaft portion 25b. It is comprised by the small diameter axial part 25a of the outer diameter which can be inserted in.

The large-diameter shaft portion 25b has an axial line in a direction orthogonal to the axial line of the shaft body 23, and both end portions of the shaft of the support shaft 27 inserted into the elongated hole 23b and supported so as to be movable in the axial direction. Fixed. The support shaft 27 prevents the holder 25 from rotating relative to the shaft body 23. The holder 25 has three housing gaps 25d extending in the axial direction at equal intervals around the axis, and is formed with an axial length extending from the lower portion of the large-diameter shaft portion 25b to the lower portion of the small-diameter shaft portion 25a. Is done.

A holding arm 29 as a holding member is supported in each housing gap 25d of the holder 25 so as to be swingable about a shaft 25f provided on the upper portion of the holder 25. A claw portion 29a that can be engaged with the lower surface of the recess 3e at the periphery of the through hole 3d is provided at the distal end portion (the lower portion in the drawing) of each holding arm 29. Each holding arm 29 has the claw portion 29a approaching each other by the elastic force of a compression elastic member 31 such as a compression spring mounted in a spring mounting hole 25g formed in the large-diameter shaft portion 25b, and enters the accommodation gap 25d. It is oscillated in the reduced diameter direction.

Note that the compression elastic member 31 described above in the present invention is not necessarily required, and the center of swinging is performed so that each holding arm 29 swings with respect to the holder 25 in the reduced diameter direction in which the claw portions 29a approach each other by its own weight. Any configuration may be used as long as it is set to support the shaft.

A fixed plate 33 having a through hole 33a through which the shaft body 23 is inserted is fixed at the center of the upper surface of the holder 25, and an axial line is provided on the outer peripheral side of the fixed plate 33 in the vertical direction shown in the figure. The three shafts 35 having a required length are attached at equal intervals around the axis. A retaining plate 39 having an opening 39 a through which the shaft body 23 and a tensile elastic member 37 described later are inserted is fixed to the upper end portion of each shaft 35. Further, a slide plate 41 is supported on each shaft 35 so as to slide in the axial direction between the fixed plate 33 and the retaining plate 39.

The elastic force of the tension elastic member 37 is set to a value that receives and balances the weight of the entire holder 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41.

An unlocking cam 43 is attached on the fixed platen 33 coinciding with the engaged recess 23c. The unlocking cam 43 has a cam surface whose tip rises along the outer peripheral surface of the shaft body 23 and gradually increases in width from the tip to the bottom.

A support shaft 45 having an axis extending in the radial direction is supported on the slide plate 41 corresponding to the lock release cam 43 so as to slide in the radial direction, and a tip end portion (shaft body) of the support shaft 45 is supported. 23), an engaging claw portion 47 that engages with the engaged recess 23c is attached. A taper surface facing the cam surface is formed on the lower surface of the engaging claw portion 47 facing the cam surface of the unlocking cam 43. Further, the engaging claw portion 47 is biased so as to engage with the engaged recess 23c by a compression spring 49 as a first elastic member mounted on the support shaft 45.

Further, one end of the slide disk 41 is hooked on the upper portion of the shaft body 23, and a plurality of (three in this example) tension springs 37 such as tension springs are arranged at equal intervals in the circumferential direction. The ends of the elastic member 37 are pulled so that the holders 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41 move upward in the axial direction. Energized by elastic force.

Next, the operation of forming the opening 7 by the tank drilling device 1 configured as described above will be described.
First, the initial state of the tank drilling device 1 will be described. The holder 25 including the fixed plate 33, the retaining plate 39 and the slide plate 41 is pulled against the shaft body 23 against the elastic force of the elastic member 37. The engaging claw portion 47 moved downward along the axis and urged by the elastic force of the compression spring 49 is engaged with the engaged recessed portion 23c to keep the moving state. At this time, the holding arms 29 are moved in the direction in which the holding portions 29a approach each other due to the elastic force of the compression elastic member 31, and are slid in the reduced diameter direction so as to contact the cam surface 23a of the shaft body 23. Is done. Further, the cam surface of the unlocking cam 43 is close to the tapered surface of the engaging claw portion 47. (See Figure 3)

  Next, in order to form the opening 7 in the upper surface plate 3b of the component mounting portion 3 by the tank punching device 1 described above, the tank drilling device 1 is controlled by moving the arm of the work robot and the small diameter shaft portion of the holder 25. 25a is inserted into the through hole 3d of the recess 3e and protrudes into the vehicle fuel tank 5, and is moved so that the lower surface of the large diameter shaft portion 25b contacts the bottom surface of the recess 3e. At this time, the cutting edge of the cutting blade 17 is separated from the upper surface of the upper surface plate 3b with a predetermined interval. (See Figure 4)

  Next, when the tank drilling device 1 is further moved downward in the axial direction with respect to the vehicle fuel tank 5 in the above state, the holder 25 is moved upward in the axial direction by the contact of the large diameter shaft portion 25b with the bottom surface of the recess 3e. Move to. At this time, the cam surface of the unlocking cam 43 provided on the stationary platen 33 that moves integrally with the holder 25 in the axial direction comes into pressure contact with the tapered surface of the engaging claw portion 47 so that the engaging claw portion 47 is compressed to the compression spring 49. It moves in the radial direction against the elastic force of and releases the engagement with the engaged recess 23c.

As a result, the holder 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41 is moved upward by the elastic force of the tensile elastic member 37, and each holding arm 29 is resisted by the elastic force of the compression elastic member 31. By swinging away from each other, each holding portion 29a protrudes outward from the accommodation gap 25d and is moved to the diameter expansion position side where it can engage with the lower surface of the recess 3e at the periphery of the through hole 3d. (See Figure 5)

As described above, since the elastic force of the tension elastic member 37 is set to a value that receives the weight of the entire holder 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41, the tensile elastic member 37. The holder 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41 is not moved upward along the axis due to the elastic force. As a result, the holding portions 27a of the holding arms 29 are kept in a non-abutting state in which the holding portions 27a can be engaged with the lower surface of the recess 3e at the periphery of the through hole 3d at a predetermined interval.

In this state, while the tank drilling device 1 is moved further downward along the axis with a required stroke, the cutting blade 17 that rotates around the spindle 9 is pressed against the upper surface plate 3b and driven by the drive of the electric motor 11. At the time of this cutting, each holding arm 29 is kept in a state of swinging in the diameter-expanding direction by the shaft body 23 moving downward with respect to the holder 25, and each holding portion 29a has a recess 3e around the through hole 3d. It is kept in a non-abutting state in which it can be engaged with the lower surface of the substrate at a required interval. (See Figure 6)

At the time of cutting the upper surface plate 3b by the cutting blade 17, the shaft body 23 supported so as to rotate freely with respect to the rotating spindle 9 is a frictional force caused by the pressure contact of the large-diameter shaft portion 25b with the bottom surface of the recess 3e. Thus, the rotation with the spindle 9 is restricted.

Then, when the opening 7 is formed in the upper surface plate 3b by the cutting action, the cut piece 3f separated from the upper surface plate 3b moves downward with respect to the small diameter shaft portion 25a of the shaft body 23 by its own weight, and the diameter is increased. Each holding portion 29a moved to the position side is engaged with the lower surface of the recess 3e of the through-hole 3d to be prevented from being detached. (See Figure 7)

After the opening 7 is formed in the component mounting portion 3 by the above-described action, the arm of the work robot is controlled to move away the tank drilling device 1 from the component mounting portion 3 and move to the discharge position of the cut piece 3f. Then, the tank punching device is in a state in which the arm portion 51a of the substantially U-shaped removal jig 51 is in contact with the upper surface of the retaining plate 39 of the holder 25 that has been moved above the axis of the shaft body 23. 1 is removed and controlled to move away from the jig 51, and the holder 25 including the fixed plate 33, the retaining plate 39, and the slide plate 41 is pulled against the shaft body 23 against the elastic force of the elastic member 37. The engaging claw 47 urged by the compression spring 49 is engaged with the engaged recess 23c by moving downward. (See Figure 8)

As a result of the above movement, the shaft 23 moves upward with respect to the holder 25 so that the holding arms 29 urged by the elastic force of the compression elastic member 31 are positioned in the receiving gaps 25d. The holding piece 29a is released from holding by the holders 29a. Note that the cut piece 3f released from being held by each holding portion 29a is pulled out from the small-diameter shaft portion 25a of the holder 25 by its own weight.

  In this embodiment, at the time of cutting, the holding blade 29a of each holding arm 29 that swings in the diameter expanding direction is moved to the lower surface of the recess 3e at the periphery of the through hole 3d so that the cutting blade 17 rotates. Thus, by allowing the cut piece 3f cut from the upper surface plate 3b to be held, it can be prevented from falling into the vehicle fuel tank 5.

Further, when the small diameter shaft portion 25a of the holder 25 is inserted into the through hole 3d of the recess 3e during cutting, the moving state of the holder 25 relative to the shaft body 23 is changed by the engaging claw portion 47 that engages with the engaged recess 23c. It can be securely inserted and securely inserted. After the small-diameter shaft portion 25a is inserted into the through-hole 3d, the engagement of the engagement claw portion 47 with the engaged recess 23c is reliably released by the lock release cam 43, and the holder 25 with respect to the shaft body 23 is removed. The holding arms 29 can be swung toward the diameter expansion position by enabling movement.

DESCRIPTION OF SYMBOLS 1 Tank drilling device 3 Component attachment part 3a Male screw 3b Top plate 3c Cylindrical part 3d Through hole 3e Recess 3f Cutting piece 5 Vehicle fuel tank 7 as a tank 9 Opening 9 Spindle 11 Electric motor 13 Rotating body 13a Balancer member 15 Cutlery Mounting arm 17 Cutting blade 19 Coupling rotary body 19a Shaft portion 21 Bearing 23 Shaft body 23a Cam surface 23b Long hole 23c Engaging recess 25 Holder 25a Small diameter shaft portion 25b Large diameter shaft portion 25c Shaft hole 25d Housing gap 25f Shaft 25g Spring mounting Hole 27 Support shaft 29 Holding arm 29a as a holding member Holding portion 31 Compression elastic member 33 Fixed plate 33a Through hole 35 Shaft 37 Tension elastic member 39 Stopping plate 39a Opening portion 41 Slide plate 43 Lock release cam 45 Support shaft 47 Engagement Claw part 49 Compression spring 51 as first elastic member Removal jig 51a Arm part

Claims (2)

In a tank drilling device in which a cutting blade provided at a required distance in the direction perpendicular to the axis from the axis of the rotationally driven spindle is rotated around the spindle to form a hole in the component mounting portion of the tank.
A shaft body whose base end portion is pivotably supported with respect to the shaft end portion of the spindle, and a cam surface is provided at the distal end portion;
A small-diameter shaft portion having an outer diameter that can be moved in a predetermined stroke in the axial direction with respect to the shaft body and is inserted in a state of being prevented from rotating, and can be inserted into a through-hole previously drilled in the component mounting portion, and At least two accommodation gaps having an outer diameter large diameter shaft portion that contacts the periphery of the through hole, communicating with the shaft hole into which the shaft body is inserted, and having an axial length extending over the large diameter shaft portion and the small diameter shaft portion A holder formed with,
Proximal ends at the housing gap in the holder is rotatably supported to be pivotal, a holding portion provided on a more distal portion sliding against the outer circumferential surface of the shaft including the cam surfaces to the diameter direction rocking engageable with the holding arm to the lower surface of the through hole periphery by moving,
A slide board that is inserted into the shaft body and supported so as to be movable in the axial direction in a state in which the shaft body is prevented from being detached .
An engagement claw portion that is provided on the slide disk so as to be movable in the direction orthogonal to the axis, and that is urged by the elastic force of the first elastic member and whose tip portion can engage with an engaged recess provided in the shaft body. When,
The engaging claw portion provided in the holder and engaged with the engaged recess as the shaft body enters the shaft hole moves in the disengagement direction against the elastic force of the first elastic member. An engagement release cam that releases the engagement and enables the slide disc to move in the axial direction with respect to the shaft body ;
A tension elastic member that urges the holder to move to the base end side through a slide disc secured to the support shaft with respect to the shaft body;
Equipped with a,
When forming a hole in the component mounting portion with the rotating cutting blade, the small diameter shaft portion is inserted into the through hole of the component mounting portion, and the large diameter shaft portion is brought into contact with the upper peripheral surface of the through hole to move the holder. When the shaft body is moved in the insertion direction in a restricted state, the holding arm that slides in contact with the outer peripheral surface including the cam of the shaft body swings in the diameter increasing direction, and the holding portion that protrudes from the accommodation gap is formed in the through hole. The first elastic member is elastically engaged with the engagement claw portion engaged with the engaged recess as the shaft moves with respect to the holder. The holder is moved to the disengagement direction against the disengagement to release the engagement, and the holder is moved to the base end side of the shaft body through the slide disc that is prevented from being pulled out by the elastic force of the pulling elastic member. Each holding arm is maintained while the shaft body enters the holding state, and the holding portion protrudes from the accommodation gap. While retaining the dynamic state,
When a hole is formed in the component mounting part due to the progress of cutting by the rotating cutting blade, the holder arm moves to the base end side of the shaft body by the elastic force of the tensile elastic member, and the swinging state of the holding arm is changed. A tank hole punching device that makes it possible to restrict the cutting piece from falling out of the holder by maintaining the engagement state of the holding portion with respect to the lower surface periphery of the through hole in the cutting piece held and separated from the component mounting portion . In claim 1,
The holder has an axis in a direction orthogonal to the axis, and the shaft end of the support shaft supported so as to slide in the axial direction in a long hole formed in the shaft is fixed to the shaft. A tank drilling device that supports the holder so that it can be moved in the axial direction with the holder being prevented from rotating.

Images