JP2014000648A - Work tank of electrical discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work tank of an electrical discharge device capable of opening or closing a front door while elevating the front door by simple operation.SOLUTION: A work tank 11 of an electrical discharge device including: a front door 20; drive means 40; and drive transmission means 41, includes: L-rails 32 and 33 each provided on each of both side surfaces of the work tank 11, and each including a vertical portion and a longitudinal portion extending rearward of the work tank 11 from an upper end of the vertical portion; and a vertical rail 36 provided on at least one of the side surfaces of the work tank 1, and extending vertically. The front door 20 includes a bracket 21 projecting outward of each of both the side surfaces of the work tank 11. The bracket 21 includes: first guides 26 and 27 engaged with the L-rails 32 and 33, respectively; a lever 24 swingably and pivotally supported by the bracket 21 via a pivotal portion 24A, and having a drive coupled portion 24B located forward of the pivotal portion 24A and coupled to the drive transmission means 41; and a second guide 24C located forward of the pivotal portion 24A of the lever 24, and engaged with the vertical rail 36.

Description

  The present invention relates to a machining tank of an electric discharge machining apparatus that stores machining fluid and performs electric discharge machining, and more particularly to a machining tank of an electric discharge machining apparatus having a front door that can be opened and closed automatically.

  The electric discharge machining apparatus includes a machining tank that accommodates and places a workpiece in order to immerse the workpiece in a machining fluid and perform electric discharge machining. Such a processing tank is required for both the wire-cut electric discharge machining apparatus and the die-sinking electric discharge machining apparatus. This processing tank is provided with a front door that can be opened and closed on the front surface, and is opened and closed as necessary for preparation of electric discharge machining and maintenance of the machining tank.

  It is preferable that the front door can be opened and closed by a simple operation and that the space necessary for opening and closing is small in order to secure a space necessary for maintenance work of the processing tank. For this reason, as described in Patent Documents 1 to 3, a manual or mechanically driven front door that is opened and closed by sliding up and down is used. Furthermore, in order to avoid the enlargement of the electric discharge machining apparatus, it is required to make the opening / closing mechanism of the front door more compact.

International Publication No. 2002/064298 Japanese Patent Laid-Open No. 11-77435 JP 2001-105243 A

  However, the front door described in Patent Document 1 needs to be locked (or unlocked) using a fixing means such as a bolt before and after the front door is raised and lowered. For example, the front door is manually lifted to the closed position. It is necessary to lock the front door with a tool or the like while holding it in the closed position as it is, and the operation required for opening and closing has become a burden. In addition, since the mechanically driven front door described in Patent Document 2 moves only in the vertical direction, the packing provided on the front door and the edge of the opening of the processing tank facing this always slide, In order to drive the front door in opposition to the frictional force due to sliding, it is necessary to prepare a drive device having a relatively large power, and the device tends to increase in size. In order to lock the front door, the front door described in Patent Document 3 needs to perform a locking operation in which the handle is moved downward after the front door is brought into close contact with the processing tank.

  Then, this invention was made | formed in view of the said situation, and it aims at providing the processing tank of the electric discharge machining apparatus which can open and close a front door easily using a compact opening / closing mechanism.

  The processing tank of the electrical discharge machining apparatus according to the present invention moves upward to close the front face, moves downward to open the front face, and moves up and down to move the front door up and down. A machining tank of an electric discharge machining apparatus for storing machining fluid, wherein the machining tank is provided on both side surfaces of the machining tank, and a drive transmission means for transmitting a driving force of the driving means to the front door. An upper and lower portion extending vertically, an L-shaped rail portion including a front and rear portion extending rearward of the processing tank at an upper end of the upper and lower portions, and an upper and lower rail portion provided on at least one side surface and extending vertically. The front door includes a bracket protruding to the outside of both side surfaces of the processing tank, and the bracket engages with the L-shaped rail portion so as to be movable along the L-shaped rail portion; , Swingable to the bracket via a shaft support A lever that is supported and connected to the drive transmission means at a drive connecting portion located in front of the shaft supporting portion, and that is inclined at a predetermined angle when the front door is in an open state, and the shaft supporting portion provided on the lever A second guide portion that is positioned further forward and engages with the upper and lower rail portions so as to be movable along the upper and lower rail portions, and the driving means moves the lever upward via the drive connecting portion. Then, while the first guide part ascends the upper and lower parts of the L-shaped rail part, the lever is tilted at the predetermined angle as the drive connecting part ascends, and the bracket and the front part are inclined. After the door rises and the first guide portion reaches the front and rear portions of the L-shaped rail portion, the lever rotates about the shaft support portion as the drive connecting portion rises. The first guide part moves the front and rear parts. The bracket and the front door is moved, characterized in that the said front door to move backward is closed towards.

  Here, the “predetermined angle” means that the front door is inclined at a predetermined angle with respect to the front-rear direction of the front door so that the front side of the front door is lowered.

  In the machining tank of the electric discharge machining apparatus according to the present invention, it is preferable that the upper and lower portions and the front and rear portions of the L-shaped rail portion are connected by a refracting portion having a rounded corner.

 Moreover, in the machining tank of the electric discharge machining apparatus according to the present invention, the front and rear portions of the L-shaped rail portion may be inclined so that the front side is lowered.

 Moreover, in the machining tank of the electric discharge machining apparatus according to the present invention, the front and rear portions of the L-shaped rail portion may be inclined so that the front side is lowered.

  In addition, when the front and rear portions of the L-shaped rail portion are inclined so that the front side is lowered, the inclination facilitates the front door to move forward, and the front door moves along the front and rear portions of the L-shaped rail portion. When the front door is tilted, a part of the front door (if the front door is provided with a seal member (packing) made of foam rubber or the like to liquid-tighten the space between the front door and the processing tank Is preferably a value in a range where a part of the seal member does not hit the front surface of the processing tank. Moreover, it is preferable that the inclination of the front-and-rear part of the L-shaped rail part is a value within a range in which the first guide part does not move the front-and-rear part forward only by the weight of the front door. For this reason, for example, the front and rear portions of the L-shaped rail portion preferably have an inclination of 0 to 30 degrees with respect to the front and rear direction, and more preferably have an inclination of 0 to 15 degrees. Further, the entire front and rear part may be inclined, or only a part of the front and rear part such as the front part of the front and rear part may be inclined.

  Moreover, in the machining tank of the electric discharge machining apparatus according to the present invention, the upper and lower rail portions and the second guide portion can be any member, shape, or shape as long as they can guide the second guide portion up and down by engaging with each other. A structure may be used. For example, it is preferable that the upper and lower rail portions are upper and lower grooves, and the second guide portion is a cam follower that engages with the upper and lower grooves.

  Further, in the machining tank of the electric discharge machining apparatus according to the present invention, the L-shaped rail portion and the first guide portion can be any members as long as they can guide the first guide portion up and down by engaging with each other. Shapes and structures may be used. For example, it is preferable that the L-shaped rail portion is two L-shaped grooves arranged in parallel, and the first guide portion is two cam followers that engage with the two L-shaped grooves. .

  Further, in the machining tank of the electric discharge machining apparatus according to the present invention, the drive connecting portion is disposed in front of the second guide portion, and the shaft support portion, the second guide portion, and the drive connecting portion are positioned on a straight line. Preferably not.

  In the machining tank of the electric discharge machine according to the present invention, when the driving means moves the lever upward through the drive connecting portion, the drive connecting portion is moved while the first guide portion is raised above and below the L-shaped rail portion. As the lever rises, the bracket and the front door rise while the lever is tilted at a predetermined angle, and after the first guide portion reaches the front and rear portions of the L-shaped rail portion, the drive connecting portion rises. The lever rotates around the shaft support, the first guide moves the front and rear parts backward, and the bracket and the front door move backward to close the front surface of the processing tank.

  For this reason, the closing operation is completed simply by urging the lever with an upward force, and the opening operation is completed simply by urging the lever with a downward force. Therefore, the front door can be sealed and opened smoothly and easily. Can be done. In addition, the front door moves up and down with the front door positioned slightly forward from the front of the processing tank, and the front door moves back and forth when the front door is attached to and detached from the front of the processing tank. Even when a member such as packing is attached to prevent the machining fluid from leaking inside, the packing is not moved while sliding up and down with the machining tank. Therefore, compared to the case where the front door moves up and down while sliding the inside of the front door with the processing tank, the front door can be moved up and down with a small force because there is no frictional force caused by sliding. Since a compact driving means with a small output can be applied, the front door opening / closing mechanism can be miniaturized.

  Further, in the machining tank of the electric discharge machining apparatus of the present invention, when the upper and lower portions of the L-shaped rail portion and the front and rear portions are connected by a refracting portion having a rounded corner, the vertical direction is changed to the front and rear direction. It is preferable because the moving direction can be changed smoothly.

  Further, in the machining tank of the electric discharge machining apparatus of the present invention, when the front and rear portions of the L-shaped rail portion are inclined so that the front side is lowered, the first guide portion can be moved forward more easily. it can.

  Further, in the machining tank of the electric discharge machining apparatus of the present invention, when the drive connecting portion is disposed in front of the second guide portion, and the shaft support portion, the second guide portion, and the drive connecting portion are not positioned on a straight line. Since the drive connecting portion is arranged in front of the second guide portion, the force of the drive means can be increased and transmitted to the first guide portion by the lever principle, and the output of the drive means is relatively Even if it is small, the front door can be opened and closed. Further, since the shaft support portion, the second guide portion, and the drive connection portion are not positioned on a straight line, the drive connection portion of the drive connection portion is more than the case where the shaft support portion, the second guide portion, and the drive connection portion are positioned on a straight line. Since the displacement in the front-rear direction can be suppressed, it is easy to apply a drive means that moves up and down linearly to move the drive connecting portion.

1 is an overall view showing an outline of an electric discharge machining apparatus including a machining tank according to a first embodiment of the present invention. The right view of the front part of the processing tank which concerns on the 1st Embodiment of this invention. The top view which expands and shows the clamp lever periphery of FIG. 2 partially. Front view of FIG. The figure showing the modification of an L-shaped guide groove. The right view of the front part of the processing tank which concerns on the 2nd Embodiment of this invention. The top view which expands and shows the clamp lever periphery of FIG. 6 partially. AA sectional drawing (front view) of FIG. The figure explaining the operation | movement locus | trajectory of the clamp lever in the modified example of a clamp lever, and closing operation | movement.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of an electric discharge machining apparatus 10 that employs a machining tank 11 having an opening / closing mechanism for a front door 20 according to a first embodiment of the present invention. The electric discharge machining apparatus 10 moves in a horizontal direction (X-axis direction) perpendicular to the Y-axis direction, a bed 12, a saddle 17 installed on the bed 12 so as to be movable in the Y-axis direction (a predetermined direction in the horizontal direction). Possiblely, a table 18 installed on the saddle 17 and a processing tank 11 installed on the table 18 are provided. Further, the workpiece WP is disposed on the work stand WS in the processing tank 11. A column 14 is erected vertically at the rear of the bed 12. The upper guide assembly 15 and the lower guide assembly 16 that support the wire electrode EL are respectively supported by the upper arm 13 and the lower arm 19 that extend from the column 14, and are disposed so as to face each other with the workpiece WP interposed therebetween.

  The electric discharge machining apparatus 10 displaces the saddle 17 in the Y-axis direction by a control means (not shown) while supplying a machining voltage from a power supply device for electric discharge machining (not shown) to the workpiece WP and the wire electrode EL. By displacing the table 18 in the direction, the workpiece WP placed on the table 18 is made relatively to the wire electrode EL supported by the upper guide assembly 15 and the lower guide assembly 16 along a desired path. The electric discharge machining can be performed.

  FIG. 2 is a side view of the processing tank 11 according to the first embodiment. In FIG. 2, the closed front door 20 that is closed so that the machining fluid does not leak is indicated by a solid line, and the open front door 20 that is the most open state is indicated by a two-dot chain line.

  The processing tank 11 in this embodiment performs the opening | closing operation | movement and closing operation | movement of a front door by driving the clamp lever attached to the front door 20 so that rocking | fluctuation was possible. Here, the closing operation is a front door that moves the front door 20 raised to the raised position to the processing tank 11 side in order to raise the front door 20 and close the front door 20 against the processing tank 11. It consists of 20 backward movements. The opening operation is an operation for performing the closing operation in the reverse order, and the front door 20 is moved forward from the position where the front door 20 is pressed against the processing tank 11 to a position where the front door 20 can be lowered. The front door 20 is lowered.

  As shown in FIG. 2, an opening 11 </ b> A is opened on the front surface of the processing tank 11. A packing 22 is attached to the front door 20 covering the opening 11A so as to prevent the machining liquid from leaking so as to face the periphery of the opening 11A. In the vicinity of both sides of the front door 20, brackets 21B and 21C (see FIG. 1) are detachably attached so as to sandwich the right side wall 11B and the left side wall 11C (see FIG. 1) of the processing tank 11, respectively. This is because it is necessary to remove the door for maintenance work such as replacement of the packing 22.

  A rail block 31 (rail member) is attached to both side walls 11B and 11C of the processing tank 11 along the front end, and a first L-shaped guide groove 32 and a second L-shaped guide groove 33 (L-shaped). Rail part) is formed. The rail block 31 is made of engineering plastic having excellent wear resistance and friction resistance, and the first L-shaped guide groove 32 is processed from the upper and lower portions 32V formed of grooves extending in the vertical direction and the upper ends of the upper and lower portions. It is formed as an L-shaped groove composed of front and rear portions 32H formed of grooves extending in the front-rear direction toward the rear side of the tank. The second L-shaped guide groove 33 has the same shape as the first L-shaped guide groove 32 formed in parallel with the first L-shaped guide groove 32 having a different height and horizontal position. Similar to the first L-shaped guide groove 32, the upper and lower portions 33V are formed of grooves extending in the vertical direction, and the grooves are extended in the front-rear direction from the upper ends of the upper and lower portions toward the rear side of the processing tank. It is formed as an L-shaped groove composed of the front and rear portions 33H.

  An upper and lower rail member 35 in which an upper and lower guide groove 36 is formed is attached in parallel to the rail block 31 on the side walls 11 </ b> B and 11 </ b> C of the processing tank 11 next to the rail block 31. When the front door 20 moves up and down, the first and second cam followers 26 and 27 move up and down along the L-shaped guide grooves 32 and 33, and the clamp cam follower 24C moves up and down along the vertical guide groove 36. Moving.

  The brackets 21B and 21C include a first cam follower 26 and a second cam follower 27, which are first guide portions, and the first and second cam followers 26 and 27 are formed on a rail block 31 (rail member). The first L-shaped guide groove 32 and the second L-shaped guide groove 33 thus inserted are respectively guided.

  Each of the brackets 21B and 21C includes a clamp lever 24 that is pivotally supported by an attachment shaft (shaft support portion) 24A. The clamp cam follower 24C attached to the front side of the attachment shaft 24A of the clamp lever 24 is inserted into the vertical guide groove 36 and guided.

  The processing tank 11 has an upper pulley 43U disposed above the upper and lower guide grooves 36 and a lower pulley 43L disposed below the both sides of the processing tank 11, and a toothed belt stretched around the pulley. (Timing belt) 41 (drive transmission means) is provided, and only the right side surface of the processing tank 11 is provided with a servo motor 40 (drive means) that moves the front door 20 of the processing tank 11 up and down to open and close. Further, a timing belt 40A is stretched between the servo motor 40 and the lower pulley 43L provided on the right side surface so that the lower pulley 43L rotates in synchronization with the drive of the servo motor 40. It is configured.

  In the first embodiment, as shown in FIG. 2, the servo motor 40 is disposed at a position where the rotational drive shaft is parallel to the rotational shaft of the lower pulley 43 </ b> L provided on the right side surface of the processing tank 11. Is done. The driving force of the servo motor 40 may be transmitted to the upper pulley 43U instead of the lower pulley 43L. Further, as long as the driving force of the servo motor 40 can be transmitted to the lower pulley 43L, the servo motor 40 and the lower pulley 43L (or the upper pulley 43U) may be coupled so that the rotation axis is coaxial. Further, an alternative means such as a chain may be used instead of the timing belt 40A, and further parts such as one or more gears may be used.

  FIG. 3 is an enlarged plan view showing a connecting portion between the clamp lever 24 and the belt 41. As shown in FIG. 3, a connecting shaft 24 </ b> B (drive connecting portion) is attached to the clamp lever 24 and is rotatably supported by a ball bearing 48 </ b> A in the connecting housing 48. In addition, a belt lock member 48 </ b> C for fixing the belt 41 to the clamp lever 24 by sandwiching the belt 41 with the connection housing 48 is attached to the connection housing 48. As shown in FIG. 3, since the belt 41 is connected to the clamp lever 24 by being sandwiched between the connection housing 48 and the belt lock member 48C, when the servo motor 40 is driven to rotate the lower pulley 43L, The belt 41 travels, and the clamp lever 24 fixed to the belt 41 swings. Thus, the belt 41 transmits the driving force of the servo motor 40 to the clamp lever 24. The connecting shaft 24B is coaxially connected to the shaft of a clamp cam follower 24C attached to the clamp lever 24.

  FIG. 4 is a right front view of the processing tank 11 with the front door 20 of the processing tank 11 shown in FIG. 2 removed. The upper pulley 43U provided on the right side surface 11B (and the left side surface 11C) has a pulley shaft 44 and is fixed so as to rotate via a bearing 46. The lower pulley 43L provided on the right side surface 11B (and the left side surface 11C) is fixed to a pulley shaft 45 connecting the left and right lower pulleys 43L so as to rotate via bearings 47, respectively. Since the left and right lower pulleys 43L are connected to a common pulley shaft 45, when the belt 41 stretched between the upper pulley 43U and the lower pulley 43L is driven by the servo motor 40, the both side walls 11B and 11C The upper pulley 43U and the lower pulley 43L provided respectively rotate in conjunction with each other. The bearing 47 is accommodated in the housing 47A. The housing 47A can be adjusted up and down for attaching / detaching the belt or absorbing the stretch, and also functions as a known take-up.

  As described above, in the present embodiment, the upper pulley 43U, the lower pulley 43L, and the belt 41 respectively provided on the both side surfaces 11B and 11C are used, and the driving force of the servo motor 40 is transferred to the both side surfaces via the connecting shaft 24B. The front door 20 is moved by transmitting to the bracket at the same time. For this reason, when the front door 20 moves, the brackets 21B and 21C on both sides can be moved synchronously, and problems such as the cam followers catching on the L-shaped guide grooves 32 and 33 or the vertical guide grooves 36 occur. Can be suppressed. Further, in order to make the front door 20 movable more easily, for example, as shown in FIG. 4, a torsion coil spring 49 is wound around a shaft 45 and the end thereof is fixed by a fixing bracket 49A, and the torsion coil spring 49 is twisted. It is preferable that a force slightly smaller than the weight of the front door 20 is applied to the belt 41 by the coil spring 49. In this case, since the force required to move the front door 20 can be reduced, the front door 20 can be moved with a small force. As described above, the belt 41 is not limited to the belt, and may be a chain, a wire, or the like as long as it can move the brackets 21B and 21C synchronously and can apply a predetermined driving force.

  Further, as shown in FIG. 2, the brackets 21 </ b> B and 21 </ b> C include a stopper pin 23 above the clamp lever 24 in order to define the rotation range of the clamp lever 24. The stopper pin 23 is disposed at a position where it comes into contact with the clamp lever 24 when the clamp lever 24 is tilted in the closed state. By providing the rotation restricting means for defining the rotation range of the clamp lever 24 like the stopper pin 23, even when an unintended upward force is applied to the front door 20, the clamp lever 24 is erroneously raised at the front. Therefore, it is possible to prevent the front door from moving and causing a malfunction. The brackets 21B and 21C are provided with notches 21A along the swinging path of the clamp cam follower 24C so as not to hinder the rotation of the clamp lever 24.

Further, the length in the front-rear direction of the front and rear portions 32H, 33H of the L-shaped guide grooves 32, 33 needs to be larger than the amount of displacement in the front-rear direction of the front door 20 due to the rotation of the clamp lever 24.
The lengths of the front and rear portions 32H and 33H in the front-rear direction are preferably substantially equal to the distance that the front door 20 moves forward from the position in the closed state to the position where the front door 20 can move up and down. The contraction allowance of the packing 22 in the front-rear direction and the front-rear displacement difference between the upper and lower edges of the front door 20 when the front door 20 is tilted, and some safety allowance. It is desirable to add the length. For example, the length in the front-rear direction of the front-rear parts 32H and 33H from the upper ends of the upper and lower parts 32V and 33V to the position where the first and second cam followers 26 and 27 stop is sufficiently large at least 10 mm. preferable.

  Further, the front and rear portions 32H, 33H and the upper and lower portions 32V, 33V of the first and second L-shaped guide grooves 32, 33 are connected so as to form rounded corners at the refracting portions 32C, 33C. It is preferable. In this case, it is possible to smoothly guide the first and second clamp cam followers 26 and 27 from moving vertically to moving back and forth, or switching the movement direction opposite thereto.

  FIG. 5 is a view showing a modification of the first and second L-shaped guide grooves 32 and 33 shown in FIG. As shown in FIG. 5, the front and rear portions 32H and 33H of the first and second L-shaped guide grooves 32 and 33 are lowered toward the front side of the processing tank 11, particularly in the vicinity of the refracting portions 32C and 33C. It may be inclined. In this case, the first and second clamp cam followers 26 and 27 can be moved forward with a smaller force in accordance with the movement of the brackets 21B and 21C at the start of the opening operation. When the front and rear portions 32H and 33H of the first and second L-shaped grooves 32 and 33 are inclined by θ from the direction perpendicular to the vertical direction so that the front side is lowered, the inclination θ is Facilitating forward movement, when the front door 20 moves along the front and rear portions 32H, 33H of the L-shaped guide grooves 32, 33, the front door 20 tilts and a part of the front door 20 or a part of the packing 22 It is preferable that the value is in a range that does not hit the front surface of the processing tank 11. Further, the inclination of the front and rear portions 32H and 33H of the first and second L-shaped grooves 32 and 33 is such that the first and second clamp cam followers 26 and 27 are moved to the front and rear portions 32H and 33H only by the weight of the front door 20. It is preferable that the value be within a range that does not move forward. For example, the inclination θ is preferably 0 degree or greater and 30 degrees or less with respect to the front-rear direction, and more preferably 0 degree or greater and 15 degrees or less. Further, the entire front and rear portions 32H and 33H may be inclined, or only a part of the front and rear portions such as the front portions of the front and rear portions 32H and 33H may be inclined.

  Moreover, it is preferable to provide two L-shaped grooves 32 and 33 having different heights and positions in the front-rear direction as L-shaped rail portions on the side surfaces 11B and 11C, respectively, as in the present embodiment. In this case, the front door 20 can be stably supported so as not to be tilted back and forth, and as a result, the front door 20 may be caught on the L-shaped rail portion by tilting so that the front door 20 is tilted back and forth. Since the problem can be prevented, the front door 20 can be raised and lowered smoothly.

  Further, as shown in FIG. 2, the processing tank 11 detects the position of the bracket 21 </ b> B only on the right side wall 11 </ b> B as shown in FIG. 2 in order to perform control to end the opening operation or closing operation of the front door 20. Sensors S1 and S2 are provided. That is, the front door opening detection limit switch S2 is provided at a position where the front door 20 contacts the lower end of the bracket 21B when the front door 20 is lowered, and the front door closing detection limit is set at a position where the front door 20 contacts the rear end of the bracket 21B. A switch S1 is provided. Then, the control means (not shown) for controlling the servo motor 40 receives a signal from the limit switch S2 when the lower end of the bracket 21B comes into contact with the front door opening detection limit switch S2, and ends the opening operation of the front door 20. And the drive of the servo motor 40 is stopped. Further, the control means receives a signal from the limit switch S1 when the right end of the bracket 21B comes into contact with the front door closing detection limit switch S1, determines the end of the closing operation of the front door 20, and determines the servo motor 40 The driving force is switched from the output level for closing operation to the output level for maintaining the closed state. Note that the start of the opening operation and the start of the closing operation are determined by the control means detecting that a button provided on the operation panel has been pressed. The control means performs control to rotate the servo motor 40 forward during the opening operation, and performs control to reverse the servo motor 40 during the closing operation.

  Note that the present invention is not limited to this embodiment, and any method capable of detecting the end of the opening operation and the end of the closing operation of the front door 20 is applied in order to determine the end of the opening operation and the closing operation of the front door 20. You can do it. In the above embodiment, instead of providing a sensor on the processing tank side, a sensor is provided on the bracket side, and a member that contacts the sensor at a position where the end of the opening operation and the end of the closing operation on the processing tank body side can be confirmed is provided. May be. Further, in order to determine the end of the closing operation, the inclination of the clamp lever 24 in the closed state may be detected and used instead of detecting the position of the bracket 21B.

  Next, a second embodiment of the present invention will be described. FIG. 6 shows an example of an electric discharge machining apparatus 10 that employs a machining tank 11 having an opening / closing mechanism for the front door 20 according to the second embodiment of the present invention. Here, the members that are essentially the same as those of the first embodiment described above are described with the same reference numerals, and detailed description of the components that are substantially the same as those of the first embodiment is omitted. The second embodiment basically differs from the first embodiment in that the drive means is a rodless cylinder.

  As shown in FIG. 6, the processing tank 11 includes a rodless cylinder 42 on the right side of the processing tank 11. The rodless cylinder 42 has a slide portion 42A that moves up and down along a cylinder tube 42B extending in the up-down direction. The rodless cylinder 42 is disposed at a position facing the vertical guide groove 36 so that the center line of the cylinder tube 42B is parallel to the vertical guide groove 36. 7 is an enlarged plan view showing a connecting portion between the clamp lever 24 and the rodless cylinder 42 shown in FIG. 6, and the diagram shown on the right side of FIG. 7 is a plan view of FIG. It is BB sectional drawing (right side surface). 8 is a cross-sectional view (front view) taken along the line AA of the plan view of FIG. As shown in FIGS. 7 and 8, a belt lock member 48C for fixing the belt 41 to the slide portion 42A is attached to the slide portion 42A of the rodless cylinder 42, and a connecting housing 48 is attached to the belt lock member 48C. It is attached. A connecting shaft 24B (drive connecting portion) attached to the clamp lever 24 of the bracket 21B is rotatably supported by a ball bearing 48A in the connecting housing 48. The connecting shaft 24B is coaxially connected to the shaft of a clamp cam follower 24C attached to the clamp lever 24. The rodless cylinder 42 is not provided on the left side of the processing tank 11. For this reason, the left bracket 21C differs from the right bracket 21B only in that the clamp lever 24 is not connected to the slide portion 42A, but has the same configuration left and right as the bracket 21B.

  As shown in FIGS. 7 and 8, the belt 41 is configured to be fixed to the slide portion 42A by being sandwiched between the connection housing 48 and the belt lock member 48C, and to be driven up and down by the slide portion 42A. Also in the second embodiment, similarly to the first embodiment, the processing tank 11 is disposed on both side surfaces of the processing tank 11 and below the upper pulley 43U disposed above the vertical guide groove 36 and below. Since the lower pulley 43L and the toothed belt 41 spanned around the pulley are respectively provided and the left and right lower pulleys 43L are connected to a common pulley shaft 45 as shown in FIG. When the belt 41 stretched between the upper pulley 43U and the lower pulley 43L is driven by 42A, the upper pulley 43U and the lower pulley 43L respectively provided on the both side walls 11B and 11C rotate in conjunction with each other.

  As described above, in this embodiment, the upper pulley 43U, the lower pulley 43L, and the belt 41 provided on the rodless cylinder 42 and the both side surfaces 11B and 11C are used, and the driving force is applied to the brackets on both sides via the connecting shaft 24B. At the same time, the front door 20 is moved. For this reason, when the front door 20 moves, the brackets 21B and 21C on both sides can be moved synchronously, and problems such as the cam followers catching on the L-shaped guide grooves 32 and 33 or the vertical guide grooves 36 occur. Can be suppressed. As in the first embodiment, a torsion coil spring 49 is wound around the shaft 45 as shown in FIG. 4 and a force slightly smaller than the weight of the front door 20 is applied to the belt 41 by the torsion coil spring 49. Can be.

  Further, as shown in FIG. 6, the processing tank 11 detects the position of the bracket 21 </ b> B only on the right side wall 11 </ b> B as shown in FIG. 6 in order to perform control to end the opening operation or closing operation of the front door 20. Sensors S1 and S2 are provided. That is, the front door opening detection limit switch S2 is provided at a position where the front door 20 contacts the lower end of the bracket 21B when the front door 20 is lowered, and the front door closing detection limit is set at a position where the front door 20 contacts the rear end of the bracket 21B. A switch S1 is provided. Then, the control means (not shown) that controls the rodless cylinder 42 receives the signal from the limit switch S2 when the lower end of the bracket 21B comes into contact with the front door opening detection limit switch S2, and opens the front door 20. The end is determined, and the driving of the rodless cylinder 42 is stopped. Further, the control means receives a signal from the limit switch S1 when the right end of the bracket 21B comes into contact with the front door closing detection limit switch S1, determines the end of the closing operation of the front door 20, and the rodless cylinder 42. Is switched from the output level for closing operation to the output level for maintaining the closed state. Note that the start of the opening operation and the start of the closing operation are determined by the control means detecting that a button provided on the operation panel has been pressed. The control means performs control to lower the rodless cylinder 42 during the opening operation, and performs control to raise the rodless cylinder 42 during the closing operation.

  Next, the operation of the second embodiment in which the drive means is a rodless cylinder will be described with reference to FIGS. 4 and 6 to 8. First, the closing operation of the front door 20 will be described, and then the opening operation will be described. In the first embodiment in which the driving means is a servo motor, the basic operation of each member is essentially the same as that of the other members except that the driving force transmission method is different due to different driving sources. Since this is the same as the embodiment of the rodless cylinder, the description of the operation of the first embodiment is omitted.

  When the front door 20 is in the open state, the rodless cylinder 42 is stopped, and the clamp lever 24 is inclined at an angle θ from the front-rear direction so that the front side is lowered. The control means (not shown) detects that the button provided on the operation panel (not shown) has been pressed to determine the start of the closing operation, and starts to drive the rodless cylinder 42. When the slide portion 42A of the rodless cylinder 42 moves the clamp lever 24 upward via the connecting shaft 24B, the first and second cam followers 26, 27 are moved to the first and second L-shaped grooves 32, 33. While passing through the upper and lower parts 32V and 33V, the bracket 21B (21C) and the front door 20 are raised while the clamp lever 24 is inclined at a predetermined angle in accordance with the rise of the connecting shaft 24B of the clamp lever 24, and the first The second cam followers 26 and 27 reach the refracting portion 32C at the upper end of the L-shaped rail portion.

  Next, when the slide portion 42A of the rodless cylinder 42 moves the clamp lever 24 further upward via the connecting shaft 24B, the first and second cam followers 26 and 27 attached to the bracket 21 are moved to the front and rear portions 32H, Since the bracket 21B (21C) can only move backward by being guided by 33H, the clamp lever 24 rotates around the attachment shaft 24A in accordance with the upward movement of the connecting shaft 24B, and the clamp lever 24 is attached. The shaft 24A moves backward. The brackets 21B and 21C and the front door 20 are moved backward in accordance with the backward movement of the mounting shaft 24A. Then, the rear end of the bracket 21B (21C) comes into contact with the limit switch S1 that detects the end of the closing operation, and the control means detects the signal of the limit switch S1 and the output of the rodless cylinder 42 is a size for maintaining the closed state. To close the closing operation. In the closed state of the front door 20, the upward force from the rodless cylinder 42 is a bracket at a predetermined closed state output level in consideration of the elastic force of the packing 22 and the pressure of the machining fluid from the inside of the machining tank 11. 24 is continuously added.

  In the present embodiment, as shown in FIG. 6, the clamp lever 24 is parallel to the front-rear direction in the closed state. When the clamp lever 24 is made parallel to the front-rear direction, even if a force in the front-rear direction is applied to the clamp lever 24, a vertical component force is not generated, so that the clamp lever 24 is unlikely to rotate accidentally. Even if the front door 20 is pressed forward by the machining fluid, the clamp lever 24 is thrust forward in the front-rear direction with the clamp cam follower 24C of the clamp lever 24 pressed forward against the vertical guide groove 36, and receives the pressing force. The closed state of the door 20 can be maintained satisfactorily. The clamp lever 24 may be inclined with respect to the front-rear direction in the closed state, but in this case, the clamp lever 24 is moved in the vertical direction by the forward pressure of the processing liquid in the opening 11A of the processing tank 11. Since force may be generated and the clamp lever 24 may rotate accidentally, it is preferable to set the output level for the closed state of the rodless cylinder 42 sufficiently large in order to maintain the closed state of the front door 20 satisfactorily. .

  The opening operation of the front door 20 will be described. The rodless cylinder is configured so that the control means (not shown) detects the start of the opening operation by detecting that a button provided on the operation panel (not shown) is pressed, and reverses the belt 41 during the closing operation. The output of 42 is switched to the output level for opening operation. Then, according to the downward movement of the connecting shaft 24B by the rodless cylinder 42, the clamp lever 24 rotates around the mounting shaft 24A, and the clamp lever 24 is inclined at an angle θ from the front and rear so that the front side is lowered. Then, according to the rotation of the clamp lever 24, the first and second cam followers 26, 27 move forward along the front and rear portions 32H, 33H of the L-shaped guide grooves 32, 33, resulting in the brackets 21B, 21C. And the front door 20 moves forward.

  Next, when the first and second cam followers 26 and 27 reach the upper and lower portions 32V and 33V of the L-shaped guide grooves 32 and 33, the first and second cam followers 26 are moved in accordance with the downward movement of the clamp lever 24. 27 move downward along the upper and lower parts 32V, 33V. During this time, the first and second cam followers 26 and 27 attached to the bracket 21 are guided by the upper and lower portions 32V and 33V of the L-shaped guide grooves 32 and 33, so that the bracket 21 can move only downward. Therefore, the clamp lever 24 is maintained in a state inclined by a predetermined angle. When the lower end of the bracket 21B contacts the limit switch S2 that detects the end of the opening operation, the control means detects the signal of the limit switch S2, stops the rodless cylinder 42, and the opening operation ends.

  According to the processing tank 11 according to the first and second embodiments, the closing operation is completed only by urging the clamp lever 24 with an upward force, and the downward force is urged on the clamp lever 24. Since the opening operation is completed only by this, the front door 20 can be sealed and opened smoothly and easily. Further, various drive means can be applied as long as the drive means can be easily controlled and the servo motor 40 and the rodless cylinder 42 can be driven in the vertical direction. Further, like the processing tank 11, the front door 20 is positioned slightly forward from the front surface of the processing tank 11, and then the front door 20 is moved up and down, so that the processing liquid is placed inside the front door 20. Even when a packing is attached to prevent liquid leakage, the front door is not moved while sliding the packing inside the front door with respect to the processing tank as in Patent Document 3, and driving with a relatively small output is performed. Since the device can also be applied, the opening / closing mechanism can be made compact.

  Moreover, according to 1st and 2nd embodiment, since the front door 20 is moved back in the direction which presses with respect to the processing tank 11, and a closed state is complete | finished, the packing 22 of the front door 20 is firmly fixed to the processing tank 11 Can be adhered to. Moreover, since the front door 20 is attached to and detached from the processing tank 11 in the front-rear direction, the packing 22 is hardly damaged.

  Further, as in the first and second embodiments, it is preferable to use a cam follower as the first guide portion. In this case, since it engages with the L-shaped rail portion via the rotatable roller, the first guide portion smoothly moves along the L-shaped rail portion at the bent portion of the L-shaped rail portion. be able to. Moreover, you may comprise the 1st guide part as a guide pin which does not rotate. In addition, the L-shaped rail portion and the first guide portion may be any member, shape, and structure as long as they can guide the first guide portion up and down by engaging with each other.

  As in the first and second embodiments, it is preferable to use a cam follower as the second guide portion. In this case, since it engages with the upper and lower rail portions via a rotatable roller, even if it is pressed against the side wall of the upper and lower rail portions according to the rotation of the clamp lever 24, it smoothly follows the upper and lower rail portions. Can move. Moreover, you may comprise the 2nd guide part as a guide pin which does not rotate. Note that the upper and lower rail portions and the second guide portion may use any members, shapes, and structures as long as they can guide the second guide portion up and down by engaging with each other.

  As in the first and second embodiments, when the connecting shaft 24B as the drive connecting portion and the clamp cam follower 24C as the second guide portion are provided coaxially, the driving force is applied to the clamp lever 24. Can be directly transmitted to the belt 41 as well. However, the present invention is not limited to the first and second embodiments, and the drive connecting portion can be provided at an arbitrary position of the clamp lever 24.

  FIG. 9 is a diagram partially showing the right side surface of the electric discharge machining apparatus 10, and shows a modification of the clamp lever and operations at a plurality of time points during the closing operation of the clamp lever by the center line of the clamp lever. In FIG. 9, the clamp lever 24 is configured as an L-shaped lever, and the mounting shaft 24A, the clamp cam follower 24C, and the connecting shaft 24B are arranged on the center line C of the clamp lever 24 so as to be in front in this order. Yes. In FIG. 6, the positions of the center lines of the clamp lever 24 at six points in the closed state and during the closing operation are shown with reference numerals C1 to C6 in the order of the closing operation, and the attachment shaft 24A at each point in time is shown. The center positions of the clamp cam follower 24C and the connecting shaft 24B are indicated by ◯.

  As shown in FIG. 9, when the connecting shaft 24B is disposed at a position farther than the first cam follower 24C with respect to the mounting shaft 24A, the force urged to the connecting shaft 24B is efficiently used by the lever principle. It can be enlarged and transmitted to the cam follower 24C. In FIG. 9, since the mounting shaft 24A, the clamp cam follower 24C, and the connecting shaft 24B are arranged so that l = m, the vertical force on the connecting shaft 24B is doubled with respect to the clamp cam follower 24C. Can be made to act. However, in this case, when the clamp lever 24 rotates in accordance with the opening / closing operation of the front door 20, the connection shaft 24B of the clamp lever 24 is also displaced in the front-rear direction (horizontal direction in FIG. 9). The drive transmission means connected to the shaft 24B needs to have a configuration that can permit displacement in the front-rear direction. For this reason, when the clamp lever is configured as an L-shaped lever, the servo motor 40 is employed as the drive means rather than the configuration in which the connection shaft 24B is directly connected to the rodless cylinder 42 that moves linearly up and down. The driving force of the servo motor 40 is transmitted to the rotating shaft of either one of the upper and lower pulleys so that the belt 41 spanned between the upper and lower pulleys can bend appropriately in the front-rear direction within a range where the driving force can be transmitted, It is preferable that the displacement of the connecting shaft 24B in the front-rear direction is acceptable.

  In the example shown in FIG. 9, the mounting shaft 24A, the first cam follower 24C, and the connecting shaft 24B are separated vertically by a distance n from a straight line connecting the mounting shaft 24A and the first cam follower 26. Thus, a connecting shaft 24B is provided. In this case, the displacement of the connecting shaft 24B in the front-rear direction according to the rotation of the clamp lever 24 can be made smaller than when the mounting shaft 24A, the clamp cam follower 24C, and the connecting shaft 24B are arranged in a straight line. Therefore, it is preferable from the viewpoint of making the electric discharge machining apparatus 10 compact, and is easily connected to a drive device that moves linearly in the vertical direction.

  In each of the above-described embodiments, the configuration in which the driving device is provided only on one side wall is shown. However, if necessary, the driving device is provided on the left and right side walls so as to be synchronized so that two driving devices are provided. May be.

  In the electric discharge machining apparatus 10, the clamp lever 24 is provided outside the brackets 21B and 21C. However, the clamp lever 24 may be provided inside the brackets 21B and 21C.

  The present invention described above can be implemented in various other forms without departing from the characteristic features of the present invention. Accordingly, the examples described herein are illustrative and should not be construed as limiting.

11 Processing tank 20 Front door 21 Bracket 24 Clamp lever 24A Mounting shaft (shaft support)
24B connecting shaft (drive connecting part)
24C Clamp cam follower (second guide)
26, 27 First cam follower, second cam follower (first guide part)
32, 33 L-shaped guide groove (L-shaped rail)
32C, 33C Refraction part (refraction part of L-shaped rail part)
32H, 33H Front and rear parts (front and rear parts of L-shaped rail part)
32V, 33V Upper and lower parts (Upper and lower parts of L-shaped rail part)
36 Vertical guide groove (upper and lower rail part)
40 Servo motor (drive means)
41 Timing belt (chain)
42 Rodless cylinder 43U, 43L Upper pulley, Lower pulley

Claims (6)

A front door that can be moved up and down to move the front door closed and a front door that can be moved down and opened, a drive means for moving the front door up and down, and a driving force of the drive means to the front In a machining tank of an electric discharge machining apparatus for storing machining fluid, comprising drive transmission means for transmitting to a door,
The processing tank is provided on at least one side surface provided with L-shaped rail portions provided on both side surfaces, each having an upper and lower portion extending vertically, and a front and rear portion extending rearward of the processing tank at an upper end of the upper and lower portions. The upper and lower rails extending vertically,
The front door includes brackets protruding to the outside of both side surfaces of the processing tank,
The bracket is rotatably supported along the L-shaped rail portion so as to be movable along the L-shaped rail portion, and is pivotally supported by the bracket via a shaft support portion. A lever that is connected to the drive transmission means at a drive connecting portion located in front of the shaft support and is inclined at a predetermined angle when the front door is in an open state, and is located in front of the shaft support provided on the lever. And a second guide part that engages with the upper and lower rail parts so as to be movable along the upper and lower rail parts,
When the drive means moves the lever upward via the drive connecting portion, the drive guide portion is raised while the first guide portion is raised up and down the L-shaped rail portion. Then, the bracket and the front door are raised while the lever is tilted at the predetermined angle, and after the first guide portion reaches the front and rear portions of the L-shaped rail portion, As the lever moves up, the lever pivots about the shaft support portion, the first guide portion moves the front and rear portions rearward, the bracket and the front door move rearward, and the front door moves. A machining tank of an electric discharge machining apparatus, which is closed.   2. The machining tank of an electric discharge machining apparatus according to claim 1, wherein the upper and lower parts and the front and rear parts of the L-shaped rail part are connected by a refracting part having a rounded corner.   The processing tank of the electric discharge machining apparatus according to claim 1, wherein the front and rear portions of the L-shaped rail portion are inclined so that a front side is lowered. The upper and lower rail portions are upper and lower grooves,
4. The machining tank of an electric discharge machining apparatus according to claim 1, wherein the second guide portion is a cam follower that engages with the upper and lower grooves. 5. The L-shaped rail part is two L-shaped grooves arranged in parallel,
5. The machining tank of the electric discharge machining apparatus according to claim 1, wherein the first guide portion is two cam followers that engage with the two L-shaped grooves. 6.   6. The drive connecting portion is disposed in front of the second guide portion, and the shaft support portion, the second guide portion, and the drive connecting portion are not positioned on a straight line. The processing tank of the electric discharge machining apparatus according to any one of the above.

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