JP2018193808A - Attachment attachment / detachment device - Google Patents

Abstract

To provide an attachment detaching device that does not cause looseness of an attachment in order to regulate the rotation of a screw shaft.SOLUTION: In an approaching/separating means of an attachment detaching device 1, a screw shaft 5, which has a first male thread 53 and a second male thread 54 that are reverse threads for each other by interposing an intermediate part 51 between them, is held by an intermediate support part 24 that an arm connection part 2 has so that the intermediate part 51 is unmovable and rotatable. A first female thread 43 of a movable hook 4 is screwed to the first male thread 53, and a second female thread 61 of a pressing nut 6 is screwed to the second male thread 54. A coil spring 64 that deforms elastically is interposed between the pressing nut 6 and the intermediate part 51. A member support part 25 is provided with an operation member 7 that rotates coaxially with the screw shaft 5 by receiving a rotation operation from outside and a stopper member 8 that regulates or releases the rotation of the operation member 7.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an attachment attaching / detaching device interposed between an arm of a construction machine or a rod or link of an operation cylinder and an attachment.

  For the purpose of facilitating the replacement of the attachment, an attachment attaching / detaching device interposed between the arm of the construction machine or the rod or link of the operation cylinder and the attachment is used (for example, Patent Document 1). Patent Document 1 discloses a fixed hook (first holding member) for engaging one pin (pin member) of an attachment, a movable hook (second holding member) for engaging the other pin of the attachment, and a fixed hook for the movable hook. An attachment / detachment device (attachment exchange device) is provided that includes an arm connection portion (arm attachment member) connected to an arm, a rod, or a link with an approach / separation means (interval adjustment holding mechanism) that approaches and separates from the arm. Patent Document 1 (Claim 1)).

  The approaching / separating means is a stopper member that prevents the rotation of the screw shaft while a movable hook is movably screwed to a screw shaft (screw rod) that is rotatably arranged on the lower surface of the arm connecting portion. Is provided (Patent Literature 1, [Claim 2]). The screw shaft is rotated by inserting a square wrench at the end. Thereby, the slide bracket of the movable hook screwed to the screw shaft moves (Patent Document 1, [0021]). Thereby, the attachment attaching / detaching device disclosed in Patent Document 1 facilitates the replacement work of the attachment (Patent Document 1, [0026]).

JP 07-305373 A

  In the attachment attaching / detaching device disclosed in Patent Document 1, a restraining nut (lock nut member) is fitted to the end of the screw shaft from which the square wrench is removed so that the pin of the attachment does not fall out of the movable hook, and the restraining nut is used as a stopper member. The movable hook is prevented from moving by restricting the screw shaft so that the screw shaft cannot be rotated (Patent Document 1, [0022]). The stopper member is brought into contact with the outer peripheral surface of the restraint nut (side surface of the hexagonal column) to prevent the restraint nut from rotating (Patent Document 1, [0019]).

  Since the restraining nut restricts the rotation by the stopper member, the screw shaft must be rotated until the stopper member contacts the outer peripheral surface. As a result, there is a problem that the movable hook cannot be closely engaged with the pin of the attachment and the attachment is rattled. Therefore, an arm that connects a fixed hook for engaging one pin of the attachment, a movable hook for engaging the other pin of the attachment, and an approaching / separating means for moving the movable hook toward and away from the fixed hook to the arm, rod, or link. In the attachment attaching / detaching device configured to be provided in the connecting portion, a configuration or a structure that does not cause the rattling of the attachment in order to restrict the rotation of the screw shaft was examined.

  As a result of the study, we developed a fixed hook that engages one pin of the attachment, a movable hook that engages the other pin of the attachment, and an approach and separation means that moves the movable hook closer to and away from the fixed hook. Alternatively, in the attachment attaching / detaching device configured to be provided in the arm connecting portion connected to the link, the approach / separation means includes a screw shaft having a first male screw and a second male screw that are reverse screws across the intermediate portion, and the arm connecting portion. The intermediate portion is held by the intermediate support portion so as to be immovable and rotatable, the first female screw and the first male screw of the movable hook are screwed together, and the second female screw and the second male screw of the pressing nut are engaged. Screw, and an elastic member that is elastically deformed is interposed between the pressing nut and the intermediate portion, and an operation member that rotates coaxially with the screw shaft in response to an external rotation operation is provided with the arm connecting portion. The operation support member is held in a non-movable and rotatable manner by the member supporting portion having the operation member, and the operation nut is engaged with the rotation direction of the pressing nut and the screw shaft, and is connected to the extension direction of the screw shaft so as to be freely separated from each other. Alternatively, the attachment / detachment device is characterized in that a stopper member to be released is provided on the member support portion.

  In the attachment attaching / detaching device of the present invention, the opening of the fixed hook and the movable hook into which the pin of the attachment is inserted is directed in the approaching / separating direction of the movable hook with respect to the fixed hook. Here, from the viewpoint of suppressing an increase in the size of the attachment attaching / detaching device and making it difficult to remove the pin of the attachment, the openings of the fixed hook and the movable hook are opposite to each other in the approaching / separating direction (the direction in which the non-opening sides face each other). ). The fixed hook and the movable hook whose openings are opposite to each other are inserted between the pins of the attachment, and are respectively engaged with the pins from the inside. The configuration and structure of the fixed hook and the movable hook are free.

  Further, the attachment attaching / detaching device of the present invention can be applied to any of a linear motion configuration in which the movable hook linearly approaches and separates from the fixed hook, and a swing configuration in which the movable hook swings and approaches and separates from the fixed hook. In the attachment / detachment device of the direct acting configuration, a guide parallel to the screw shaft is formed in the arm connecting portion, and the movable hook is linearly moved toward and away from the fixed hook according to the screw shaft and the guide. An attachment attachment / detachment device having a swing configuration has a swing shaft of a movable hook at an arm connection portion, and a first female screw of the movable hook and an arm connection portion according to a screw shaft whose posture is changed according to the swing of the movable hook. The intermediate support member and the member support member are rocked.

  The pressing nut can screw the second female screw into the second male screw of the screw shaft whose rotation is restricted. However, when the screw shaft can freely rotate, the second male screw and the second female screw can be rotated. The screw shaft is rotated integrally by engaging the screw with friction. When the threaded shaft engages with the pin of the attachment and the movable hook cannot move, the first male screw and the first female screw mesh with each other to restrict the rotation. In this state, when the operation member is rotated, the pressing nut rotates relative to the screw shaft, and the second female screw is screwed into the second male screw while compressing the elastic member. Examples of the elastic member include a leaf spring, an elastic rubber, or a coil spring interposed between the intermediate portion and the pressing nut.

  The operation member is composed of, for example, an operation disk having notches or holes arranged at equal intervals in the circumferential direction, and a connecting block that is externally fitted to the pressing nut from the direction in which the screw shaft extends, and is rotatably held by the member support portion. Is done. The operation member is manually rotated by a wrench attached to and detached from a protrusion protruding from the center of the operation disk, or is automatically rotated by a hydraulic drive or electric drive motor connected to a gear provided on the operation disk. An operation member that is manually rotated has an advantage that it does not rotate unexpectedly if a wrench or the like is removed. The operating member that rotates automatically has an advantage that the operating member can be rotated by remote control. The stopper member includes, for example, a notch arranged at equal intervals in the circumferential direction provided on the operation member or a pin that can be inserted into and removed from the hole.

  In the attachment attaching / detaching device according to the present invention, the screw shaft that does not move in the extending direction as the position is fixed, the first male screw that moves the movable hook, and the second male that tightens the pressing nut that rotates the operating member while compressing the elastic member. With screws. Hereinafter, the fixed hook and the movable hook that are respectively engaged with the attachment pins from the inside, the movable hook moves linearly along the screw shaft, and the elastic member interposed between the intermediate portion and the pressing nut is attached to the screw shaft. A configuration in which the first male screw is a left screw and the second male screw is a right screw when viewed from the side of the second male screw on which the operation member is provided with a coil spring to be fitted will be described as an example.

  When attaching an attachment to the attachment attaching / detaching apparatus of the present invention, the fixed hook and the movable hook are inserted between the pins of the attachment while the movable hook is brought close to the fixed hook. When the operating member is rotated clockwise from this state, the screw shaft that is still in a rotatable state rotates clockwise together with the pressing nut. At this time, since the pressing nut rotates at a fixed position, the coil spring is not compressed. As a result, the first male screw tries to come out of the first female screw of the movable hook, and the movable hook is moved away from the fixed hook. The movable hook continues to move when the operating member is rotated clockwise until it engages with the other pin of the attachment.

  When the movable hook is engaged with the other pin of the attachment, it can no longer move, and the screw shaft cannot rotate. If the operation member is further rotated clockwise from this state, the pressing nut that engages with the operation member in the rotation direction rotates clockwise and is screwed into the second male screw to compress the coil spring. Thus, when the operating member is fixed to the non-rotatable state with the stopper member while the coil spring is compressed, the attachment of the attachment to the attachment attaching / detaching device is completed. The screw shaft is in a tension state due to the repulsion of the coil spring via the pressing nut, and the movable hook obtained by screwing the first female screw with the first male screw is not rattled. Further, the operation member can rotate to a specific rotation angle at which the stopper member can be fixed within a range in which the coil spring can be compressed.

  The movable hook engaged with the other pin of the attachment does not come off because the engagement with the pin becomes more dense when the screw shaft rotates clockwise. On the other hand, if the screw shaft rotates counterclockwise in a state where the movable hook is engaged with the other pin of the attachment, there is a possibility that it will come off from the pin. Here, the counterclockwise rotation of the screw shaft relatively rotates the pressing nut clockwise, that is, the pressing nut is further screwed into the second male screw. However, the pressing nut cannot be screwed in unless the coil spring is further compressed. Thus, the counterclockwise rotation of the screw nut on the premise of the clockwise rotation of the pressing nut is virtually impossible. In this way, there is no possibility that the movable hook is detached from the other pin of the attachment.

  When removing the attachment from the attachment attaching / detaching apparatus of the present invention, first, the operation member released from the restriction by the stopper member is rotated counterclockwise. At this time, since the pressing nut pressed by the compressed coil spring increases the friction of the second male screw and the second female screw, the pressing nut and the screw shaft rotate integrally counterclockwise. The movable hook moves the first male screw into the first female screw in the counterclockwise direction of the screw shaft and moves closer to the fixed hook relative to the screw shaft whose position is fixed. As a result, the movable hook is detached from the other pin of the attachment. Thus, when the movable hook moves away from the other pin of the attachment to some extent, the attachment can be detached from the attachment attaching / detaching device.

  After removing the attachment from the attachment attaching / detaching device, if the operation member is further rotated counterclockwise, the movable hook reaches the intermediate support portion and cannot move in the direction approaching the fixed hook. The rotation of the screw shaft into which the first male screw is screwed is disabled. When the operating member is further rotated counterclockwise from this state, the pressing nut rotates counterclockwise with respect to the screw shaft that has become non-rotatable, and the second female screw is loosened from the second male screw, whereby the pressing nut Is moved closer to the operating member to restore the coil spring. When the pressing nut comes into contact with the operation member and cannot move any more, the operation member cannot be rotated, and the attachment attaching / detaching device returns to the initial state.

  The movable hook in which the first female screw is screwed to the first male screw rotates the screw shaft in a movable state, but disables the rotation of the screw shaft when the movable shaft is in a non-movable state. Further, the pressing nut in which the second female screw is screwed to the second male screw is not screwed into the second male screw as long as the screw shaft can rotate, but if the screw shaft becomes unrotatable, 2 Screwed into the male screw. Due to the difference between the functions of the first male screw and the second male screw, the screw shaft may be a square screw or a trapezoidal screw and a second male screw may be a triangular screw. The first male screw, which is a square screw or a trapezoidal screw, moves the movable hook accurately according to the rotation of the screw shaft. The second male screw, which is a triangular screw, twists the pressing nut when the screw shaft becomes unrotatable while the second male screw and the second female screw are frictionally engaged to rotate the screw shaft integrally. To be able to put.

  The elastic member is interposed between the middle portion of the screw shaft and the pressing nut. In this case, when the pressing nut is screwed into the second male screw in a state where the screw shaft is not rotatable, the elastic member is twisted between the rotating pressing nut and the non-rotating intermediate portion, and the elastic member is smoothly compressed. And may not be restored. Therefore, the elastic member may be interposed between a spacer and a pressing nut that are rotatable with respect to the screw shaft and engage with the intermediate portion in the extending direction of the screw shaft. As a result, when the pressing nut is screwed into the second male screw in a state where the screw shaft cannot be rotated, the spacer rotates with respect to the screw shaft, so that the elastic member is not twisted between the pressing nut and the flange. Can be compressed and decompressed.

  The screw shaft is directly supported by the intermediate support portion of the arm connection portion, and the second male screw is indirectly supported by the operation member held by the arm connection portion via a pressing nut. . However, in order for the screw shaft to rotate smoothly, it is preferable to support a plurality of locations directly. In particular, the side of the first male screw from the middle portion is cantilevered, and there is a concern about deformation of the screw shaft. From this, it is preferable that the screw shaft is supported by the auxiliary support portion of the arm connection portion on the first male screw side. The auxiliary support portion disposed on the first male screw side supports the opposite side of the intermediate portion with respect to the first male screw, for example, the end portion of the screw shaft.

  In addition, the movable hook has a first female screw that is longer than the movable range of the movable hook, and the screw shaft has a length that is screwed into the first female screw only within the movable range of the movable hook. It is good to have one male screw. As a result, the first male screw is surrounded by the first female screw, and the first female screw is formed on the inner peripheral surface of the cylinder. The breakage of the first male screw and the second female screw is also caused by dust or the like entering between them. From this, it is preferable to attach a sealing cover in contact with the peripheral surface of the screw shaft to both ends of the first female screw, and to prevent invasion of dust by using the space of the second female screw in which the first male screw moves as a sealed space.

  In the attachment attaching / detaching device of the present invention, the pin of the attachment does not come off from the fixed hook or the movable hook due to an external force, and the attachment does not rattle. This means that the first male screw and the second male screw, which are reverse screws, are provided on the screw shaft, and the movable hook in which the first female screw is screwed to the first male screw is moved according to the rotation of the screw shaft. The pressing nut in which the second female screw is screwed to the second male screw has an effect of elastically deforming the elastic body after the movable hook is engaged with the other pin of the attachment. The above-described effect can be better achieved if the first male screw is a square screw or a trapezoidal screw and the second male screw is a triangular screw. The operation member also has an effect that the operation member can be rotated to a specific rotation angle at which the stopper member can be fixed even after the movable hook engages the other pin of the attachment.

  The elastic member is rotatable with respect to the screw shaft. When the elastic member is interposed between the spacer and the pressing nut that engages with the intermediate portion in the extending direction of the screw shaft, the elastic member is interposed between the pressing nut and the flange without twisting the elastic member. Thus, smooth rotation of the screw shaft, and hence smooth movement of the movable hook for screwing the first female screw into the first male screw of the screw shaft are ensured. Similarly, when the first male screw side is supported by the auxiliary support portion of the arm connecting portion, the first male screw side is supported at both ends by the intermediate support portion and the auxiliary support portion. Smooth rotation, and hence smooth movement of the movable hook for screwing the first female screw into the first male screw of the screw shaft, is ensured.

  In addition, the movable hook has a first female screw that is longer than the movable range of the movable hook, and the screw shaft has a length that is screwed into the first female screw only within the movable range of the movable hook. Having one male screw reduces the risk of the first male screw and the first female screw being damaged due to external force, so that the screw shaft can be smoothly rotated, and the first female screw is screwed onto the first male screw of the screw shaft. Smooth movement of the movable hooks to be combined is ensured. In this case, it is more preferable to attach a sealing cover in contact with the peripheral surface of the screw shaft to both ends of the first female screw, and to prevent entry of dust by using the space of the second female screw in which the first male screw moves as a sealed space.

It is a right view showing an example of an attachment attaching / detaching device to which the present invention is applied. It is a front view of the attachment attaching / detaching apparatus of this example. It is a partially broken right view of the attachment attachment / detachment apparatus of this example. FIG. 3 is a front view corresponding to FIG. 2 with a protective cover removed. It is a disassembled perspective view of the principal part in the attachment attachment / detachment apparatus of this example. It is a perspective view showing an operation member, a stopper member, and a press nut. It is a partial fracture right side view showing the state where a movable hook is moved. FIG. 3 is a front view corresponding to FIG. 2 with the protective cover in a state where the movable hook is moved. It is a partially broken right side view showing the state where the movable hook is engaged with the other pin. It is a partial fracture right side view showing the state where a press nut is compressing a coil spring. FIG. 3 is a front view corresponding to FIG. 2 illustrating a state in which an operation member is fixed to be non-rotatable by a stopper member.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. For the convenience of explanation, the attachment / detachment apparatus 1 is up and down in FIG. 1, the front and rear are the left and right in FIG. 1, and the left and right are the back and front of the page in FIG. 1. As shown in FIGS. 1 to 5, the attachment attaching / detaching device 1 of the present invention is fixed to a fixing hook 3 for engaging one pin 131 of an attachment 13 with an arm connecting portion 2 for connecting an arm 11 and a link 12. A movable hook 4 that linearly approaches and separates from the hook 3 and engages the other pin 132 of the attachment 13, and an approach / separation means comprising a screw shaft 5, a pressing nut 6, an operating member 7, and a stopper member 8. It is configured with.

  The arm connecting portion 2 includes a pair of main body plates 21 for connecting the arm connecting pin 111 and the link connecting pin 121, a plate-like connecting plate 22, a plate-like intermediate support portion 24 and members orthogonal to the connecting plate 22, respectively. It is configured with the support part 25 interposed therebetween. The inner surface of the main body plate 21 and the lower surface of the connection plate 22 are guides that guide the movement of the movable hook 4 by bringing the outer surface and upper surface of the hook block 42 into sliding contact. In the connection plate 22 of this example, the plate-like auxiliary support portion 27 is brought close to the rear end (right end in FIG. 1) and is detachable by an auxiliary support portion fixing bolt 272. The auxiliary support portion 27 supports the screw shaft 5 whose tip is rotatably fitted in the screw bearing hole 271.

  The fixing hook 3 is a metal member having a substantially C-shaped cross section with a lower end protruding slightly forward from the upper end and extending from side to side. It is joined and supported by a plate-like member support portion 25 lowered from the plate 22. The fixed hook 3 is not limited to a fixed structure and may be fixed directly or indirectly to the arm connecting portion 2 as long as the movable hook 4 that moves back and forth moves toward and away from the fixed hook 3. The fixing hook 3 of the present example has the opening 31 facing forward (leftward in FIG. 1, front side in FIG. 2).

  The movable hook 4 is a metal member having a substantially C-shaped cross section with its upper end projecting rearward from the lower end and extending to the left and right. ing. The hook block 42 is provided in a hole penetrating the first female screw 43 to which the first male screw 53 of the screw shaft 5 is screwed back and forth, and a sealing cover 44 that is a rubber annular member is attached to the front and rear opening ends of the hole. doing. The sealing cover 44 is slidably contacted with the peripheral surface of the screw shaft 5 to prevent dust from entering the first female screw 43. The first male screw 53 and the first female screw 43 in this example are a trapezoidal screw and a left screw. The movable hook 4 of this example has the opening 41 facing rearward (right front in FIG. 1). As a result, the fixed hook 3 and the movable hook 4 are engaged with the pins 131 and 132 of the attachment 13 from the inside with the openings 31 and 41 facing in the reverse direction.

  The hook block 42 of this example is supported by the arm connecting portion 3 through the screw shaft 5 by screwing the first male screw 53 and the first female screw 43 of the screw shaft 5 together. The hook block 42 moves linearly in the front-rear direction without rattling by bringing the upper surface into sliding contact with the lower surface of the connection plate 22 and both outer surfaces in contact with the inner surfaces of the left and right main body plates 21, respectively. Since the screw shaft 5 is held by the intermediate support portion 24 and does not move in the front-rear direction, the screw shaft 5 changes the screwing position of the first female screw 43 with respect to the first male screw 53 when the screw shaft 5 rotates. In addition, the hook block 43 moves in the front-rear direction.

  The approaching / separating means for the movable hook 4 with respect to the fixed hook 3 includes a screw shaft 5, a pressing nut 6, an operation member 7, and a stopper member 8. The screw shaft 5 screws the first female screw 43 of the movable hook 4 to the first male screw 53, and moves the movable hook 4 back and forth by its own rotation. Further, the screw shaft 5 is screwed into the second male screw 54 with the second female screw 61 of the pressing nut 6 and rotates together with the pressing nut 6 when it can rotate, and twists the pressing nut 6 when it cannot rotate clockwise. Let me. The first male screw 53 and the first female screw 43 in this example are left and trapezoidal screws, and the second male screw 54 and the second female screw 61 in this example are right and triangular screws. The second male screw 54 is in a reverse screw relationship.

  In the screw shaft 5 of this example, the intermediate part 51 is not movable forward and backward and is rotatably supported by the intermediate support part 24, and the rear end is rotatably supported by the auxiliary support part 27. Thus, the front end is indirectly rotatably supported by the member support portion 25. Thereby, both ends of the first male screw 53 of the screw shaft 5 are supported by the intermediate support portion 24 and the auxiliary support portion 27 and rotate stably. The second male screw 54 of the screw shaft 5 is supported at both ends by the intermediate support portion 24 and the member support portion, and rotates stably.

  An intermediate portion 51 of the screw shaft 5 is a constricted portion having an outer diameter smaller than the main body diameter, and a spacer receiving ring 52 having an outer diameter larger than the main body diameter is provided along the front edge. The screw shaft 5 fits the spacer receiving ring 52 into the intermediate support hole 244 of the intermediate support portion 24, and blocks the left block 241 and the right block 242 that are substantially C-shaped in front view sandwiching the intermediate portion 51 from the left and right. By fixing to the intermediate support portion 24 with a bolt 243, the intermediate support portion 24 is held so that it cannot move back and forth and is rotatable. The attachment member that holds the intermediate portion 51 and is fixed to the intermediate support portion 24 may be an upper block and a lower block that are divided vertically, instead of the left block 241 and the right block 242.

  As shown in FIG. 6, the pressing nut 6 has a second female screw 61, and the front half (the lower left side in FIG. 5) is connected to the operation member 7 having a substantially square cross section, and the rear half (FIG. 6). The middle upper right side) has a structure in which a nut side flange 62 is projected in a radial direction from a boss protruding rearward. The pressing nut 6 of this example is configured such that a spacer 63 that engages with the spacer receiving ring 52 of the screw shaft 5 from the front is loosely fitted to the screw shaft 5, and a spacer side flange 631 and a nut side flange 62 project from the spacer 63. In between, a coil spring 64 loosely fitted to the same screw shaft 5 is interposed. The pressing nut 6 and the spacer 63 are normally rotatable independently in the rotation direction. However, when the coil spring 64 is compressed, the compressed coil spring 64 and the nut-side flange 62 and the spacer-side flange 631 are displaced due to friction. Is prevented and rotates together.

  The operation member 7 includes an operation end 71 projecting from the protective cover 26, an operation disk 72 fixed or released by the stopper member 8, and a contact surface disk 73 contacting the cover receiving recess 251 of the member support part 25. And a connecting block 74 that is externally fitted to the pressing nut 6 from the extending direction of the screw shaft 5 and is held by the member support portion 25 so as to rotate coaxially with the screw shaft 5. The operation end 71 is an operation part that imparts a rotational motion to the operation member 7. The operation end 71 in this example has a hexagonal nut shape that is rotated by engaging a wrench or the like, and an arc-shaped cutout at a point-symmetrical position so that the circumferential position of the arc-shaped cutout of the operation disc 72 can be seen. A straight mark corresponding to the diameter connecting the two is attached to the front. It can be seen that there are six arc-shaped notches in the operation disk 72 in the circumferential direction, and any arc-shaped notch faces the stopper member 8 due to the inclination of the straight mark. As long as the direction of the arc-shaped notch is known, the straight mark corresponding to the diameter of this example may not be used.

  The stopper member 8 is a cylindrical member provided with a semicircular slit 82 in the middle, and a stopper end 81 is provided in the front half from the slit 82. Like the operation end 71, the stopper end 81 in this example is a hexagonal nut that can be rotated by engaging a wrench, etc., and along the edge in the diameter direction of the slit 82 so that the circumferential position of the slit 82 can be seen. A straight line mark equivalent to the radius is attached to the front. It can be seen that the slit 82 faces the operation disk 72 when the straight mark is directed upward, and faces the opposite side of the operation disk 72 when the straight mark is directed downward. If the orientation of the slit 82 is known, the straight mark corresponding to the radius of this example may not be used.

  The operation disk 72 is a disk in which six arc-shaped notches are arranged at equal intervals in the circumferential direction. The stopper member 8 is a cylindrical member having a circular cross section with the same radius as the arc-shaped notch, and is rotatably disposed at a position where the central axis is coincident with the outer peripheral edge of the operation disc 72. A slit 82 is provided in the interference area. When the operation member 7 faces the slit 82, the operation disk 72 can rotate without receiving the interference of the stopper member 8, and the center of the stopper member 8 and the circular arc-shaped notch of the operation disk 72 coincides. When the stopper member 82 is rotated, the slit 82 is disengaged from the operation disk 72, and the side surface of the stopper member 8 is engaged with the arc-shaped cutout and cannot be rotated.

  The contact surface disk 73 is in contact with a cover receiving recess 251 provided in the member support portion 25 and stabilizes the rotation of the operation member 7. The operating member 7 has the contact disk 73 accommodated in the cover receiving recess 251 and the operating end 71 is protruded from the operating end hole 261, and the protective cover 26 is fitted into the cover receiving recess 251 to fix the cover. The protective cover 26 is fixed to the member support portion 25 with bolts 263. Thereby, the operation member 7 is rotatably held by the member support portion 25 in a state where the operation disc 72 and the contact surface disc 73 are sandwiched between the member support portion 25 and the protective cover 26. The stopper member 8 is also rotatably held by the protective cover 26 with the stopper end 81 protruding from the stopper end hole 262.

  The connecting block 74 is a cylindrical portion that fits into the operation member fitting hole 252 provided in the cover receiving recess 251 of the member support portion 25 and protrudes rearward, and is a nut fitting for fitting the pressing nut 6 from the rear. A recess 741 is provided. The nut fitting recess 741 is a transfer structure of the front half portion of the pressing nut 6 having a substantially square cross section. As a result, the pressing nut 6 is fitted into the nut fitting recess 741 of the connecting block 74 from behind and engages with the operating member 7 in the rotational direction and rotates integrally, but is movable in the extending direction of the screw shaft 5. It is. Thereby, if the screw shaft 5 becomes non-rotatable, the pressing nut 6 can be screwed into the second male screw 54 or loosened by the rotation of the operation member 7.

  A procedure for attaching the attachment 13 to the attachment attaching / detaching apparatus 1 of this example will be described. The attachment attaching / detaching device 1 includes the fixed hook 3 and the movable hook between the pins 131 and 132 of the attachment 13 with the movable hook 4 approaching the fixed hook 3 (the movable hook 4 is moved to the left in FIG. 3). 4 is inserted. The fixed hook 3 and the movable hook 4 can be inserted between the pins 131 and 132 of the attachment 13 without any problem as long as the distance between the lower ends of the fixed hook 3 and the movable hook 4 is larger than the shortest distance between the opposing peripheral surfaces of the pins 131 and 132 of the attachment 13. However, when one pin 131 of the attachment 13 is first engaged with the fixed hook 3 and then the other pin 132 is swung and lifted around the pin 131, the lower end of each of the fixed hook 3 and the movable hook 4 is lifted. The distance may be a little narrower.

  Thus, after the fixed hook 3 and the movable hook 4 are inserted between the pins 131 and 132 of the attachment 13, a wrench or the like is engaged with the operation end 71, and the operation member 7 is turned clockwise as seen in FIGS. (For convenience of illustration, a wrench or the like is omitted in FIG. 8). At this time, the movable hook 4 is in a movable state and the screw shaft 5 is also in a rotatable state. Therefore, when the rotation of the operating member 7 is transmitted to the pressing nut 6, the pressing nut 6 does not compress the coil spring 64 due to the friction of the second male screw 54 and the second female screw 61, and the screw shaft 5. Rotate clockwise as a unit. As a result, the first male screw 53 tries to come out of the first female screw 43 of the movable hook, and the movable hook 4 is moved away from the fixed hook 3 (rightward in FIG. 7).

  At this time, since the movable hook 4 moves only within a range in which the first male screw 54 is screwed to the first female screw 43, the first male screw 54 is detached from the first female screw 43 and is not exposed to the outside. Since the first female screw 43 is formed on the inner peripheral surface of the cylinder and the first male screw 54 is always covered with the first female screw 43, the first male screw 54 and the first female screw No risk of damage due to external force. Further, the opening of the first female screw 43 in the front and rear is closed by the sealing cover 44 from the peripheral surface of the screw shaft 5. As a result, there is no possibility of foreign matter entering the first female screw 43, and the rotation of the screw shaft 5 in which the first male screw 54 is screwed into the first female screw 43 is not hindered. In this way, the first male screw 54 and the first female screw 43 of the present invention are protected from the outside and ensure stable rotation of the screw shaft 5.

  When the movable hook 4 is engaged with the other pin 132 of the attachment 13, it can no longer move in the direction away from the fixed hook 3, and the screw shaft 5 is made non-rotatable as seen in FIG. At this time, if the arc-shaped notch of the operation disk 72 of the operation member 7 is exactly coincident with the stopper member 8, the stopper member 8 is rotated and engaged with the operation disk 72, and the operation member 7 is rotated. Can be regulated. However, in this case, when the screw shaft 5 is advanced or retracted even for a certain reason, the engagement between the movable hook 4 and the other pin 132 of the attachment 13 is loosened, and there is a risk of rattling. In the first place, the notch of the operation disk 72 of the operation member 7 may not coincide with the stopper member 8.

  Therefore, the attachment attaching / detaching apparatus 1 of the present invention slightly rotates the operation member 7 clockwise even after the movable hook 4 is engaged with the other pin 132 of the attachment 13. The screw shaft 5 tries to rotate clockwise together with the pressing nut 6, but cannot move with the pressing nut 6 because the movable hook 4 is engaged with the other pin 132 of the attachment 13 and cannot move. As a result, when the operation member 7 is further rotated clockwise, as shown in FIG. 10, the pressing nut 6 that engages with the operation member 7 in the rotation direction cannot rotate while compressing the coil spring 64. It rotates clockwise with respect to the screw shaft 5 and is screwed into the second male screw 54.

  Then, with the coil spring 64 compressed, as shown in FIG. 11, the stopper member 8 is rotated to shift the slit 82 from the arcuate cutout of the operation disc 72, and the stopper member 8 is inserted into the arcuate cutout. When the side surfaces are engaged, the operation member 7 is fixed so as not to rotate. Thereby, the attachment of the attachment 13 to the attachment attaching / detaching device 1 is completed. The screw shaft 5 is in a tension state in which it is pushed forward by the repulsion of the coil spring 64 through the pressing nut 6 in which the second female screw 61 is screwed into the second male screw 54, and slight advancement and retraction is allowed. Therefore, the movable hook 4 in which the first female screw 43 is screwed to the first male screw 53 is not rattled.

  With the movable hook 4 engaged with the other pin 132 of the attachment 13, if the screw shaft 5 tries to rotate clockwise, the movable hook 4 engages with the pin 132 more closely. It will not deviate from 132. On the contrary, if the screw shaft 5 tries to rotate counterclockwise while the movable hook 4 is engaged with the other pin 132 of the attachment 13, the pressing nut 6 will try to rotate clockwise. Since it is difficult to further compress 64 and screw the pressing nut 6 into the screw shaft 5, the counterclockwise rotation of the screw shaft 5 into which the pressing nut 6 is screwed is virtually impossible. Thus, the screw shaft 5 cannot be rotated, and there is no possibility that the movable hook 4 is detached from the other pin 132 of the attachment 13.

  When detaching the attachment 13 from the attachment attaching / detaching device 1, the procedure reverse to the above is basically taken. First, a wrench or the like is engaged with the stopper end 81 and rotated to release the restraint of the operation member 7 by the stopper member 8, and then a wrench or the like is engaged to the operation end 71 and rotated to rotate the operation member 7 counterclockwise. Rotate to At this time, the pressing nut 6 is pressed by the compressed coil spring 64 to increase the friction of the second male screw 54 and the second female screw 61, and thus rotates counterclockwise together with the screw shaft. As a result, the movable hook 4 is screwed into the first female screw 43 by turning the screw shaft 5 counterclockwise, so that the movable hook 4 is fixed to the fixed hook 3 relative to the screw shaft 5 whose position is fixed. It moves so as to approach, and comes off from the other pin 132 of the attachment 13. Thus, when the movable hook 4 moves away from the other pin 132 of the attachment 13 to some extent, the attachment 13 can be detached from the attachment attaching / detaching device 1.

  After the attachment 13 is removed from the attachment attaching / detaching device 1, when the operation member 7 is further rotated counterclockwise, the movable hook 4 reaches the restriction portion (for example, the intermediate support portion 24) provided in the arm connecting portion 2, As a result, it cannot move in the direction approaching the fixed hook 3. As a result, the screw shaft 5 in which the first male screw 54 is screwed into the first female screw 43 of the movable hook 4 becomes non-rotatable. When the operating member 7 is further rotated counterclockwise from this state, the pressing nut 6 rotates counterclockwise with respect to the screw shaft 5 that has become non-rotatable, and the second female screw 61 is loosened from the second male screw 54. . Thus, the pressing nut 6 moves so as to approach the operation member 7 and restores the coil spring 6. When the pressing nut 6 comes into contact with a restricting portion (for example, the bottom surface of the nut fitting recess) provided on the operation member and cannot move any more, the rotation operation of the operation member 7 becomes impossible. The initial state is restored (see FIG. 3).

1. Attachment attachment / detachment device
11 Arm
111 Arm connection pin
12 links
121 Link connection pin
13 Attachment
131 One pin
132 The other pin 2 Arm connection
21 Main plate
22 Connection board
24 Intermediate support
241 left block
242 right block
243 Block fixing bolt
244 Support hole for intermediate part
25 Member support
251 Cover recess
252 Operation member fitting hole
26 Protective cover
261 Operation end hole
262 Stopper hole
263 Cover fixing bolt
27 Auxiliary support
271 Screw bearing hole
272 Auxiliary support fixing bolt 3 Fixing hook
31 Fixed hook opening 4 Movable hook
41 Opening of movable hook
42 Hook block
43 1st female thread
44 Sealing cover 5 Screw shaft
51 Middle section
52 Spacer receiving ring
53 1st male screw
54 2nd male screw 6 Pressing nut
61 2nd female thread
62 Nut flange
63 Spacer
631 Spacer flange
64 Coil spring 7 Operation member
71 Operation end
72 Operation disc
73 Tangential disk
74 Connecting blocks
741 Nut fitting recess 8 Stopper member
81 Stopper end
82 Notch

Claims (5)

A fixing hook for hooking one pin of the attachment;
A movable hook for engaging the other pin of the attachment;
An approaching / separating means for moving the movable hook toward and away from the fixed hook;
In an attachment attaching / detaching device configured to be provided in an arm connecting portion connected to an arm, a rod or a link,
The approach and separation means is
A screw shaft having a first male screw and a second male screw, which are reverse screws across the intermediate part, is held by the intermediate support part of the arm connection part so that the intermediate part cannot be moved and is rotatable.
The first female screw and the first male screw of the movable hook are screwed together,
The second female screw and the second male screw of the pressing nut are screwed together,
An elastic member that elastically deforms is interposed between the pressing nut and the intermediate part,
An operation member that receives a rotation operation from the outside and rotates coaxially with the screw shaft is held in a non-movable and rotatable manner by the member support portion of the arm connection portion,
The operating member is engaged with the pressing nut and the rotation direction of the screw shaft, and connected to the extending direction of the screw shaft so as to be freely separated from each other.
An attachment attaching / detaching device, wherein a stopper member for restricting or releasing the rotation of the operation member is provided on the member supporting portion. The attachment / detachment apparatus according to claim 1, wherein the first male screw is a square screw or a trapezoidal screw, and the second male screw is a triangular screw. The attachment / detachment device according to claim 1, wherein the elastic member is rotatable with respect to the screw shaft, and is interposed between a spacer and a pressing nut that engage with the intermediate portion in the extending direction of the screw shaft. The attachment / detachment device according to any one of claims 1 to 3, wherein the screw shaft is supported by the auxiliary support portion of the arm connection portion on the first male screw side. The movable hook has a first female screw that is longer than the moving range of the movable hook,
The attachment attaching / detaching device according to any one of claims 1 to 4, wherein the screw shaft has a first male screw having a length that engages with the first female screw only within a moving range of the movable hook.

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