JP4666103B2 - Shot blasting equipment - Google Patents

Description

  The present invention relates to a shot blasting apparatus, and more particularly to a shot blasting apparatus suitable for shot blasting of large metal products.

  As an apparatus for shot blasting a large metal product as a workpiece, for example, a table type shot blasting apparatus described in Japanese Patent Laid-Open No. 9-047966 by the assignee of the present application is known. In this apparatus, a workpiece is placed on a rotary table, and shot blasting is performed while rotating the workpiece.

  However, when shot blasting is performed on a large metal product, in the table type shot blasting apparatus, since the workpiece is placed on the rotary table, the rotary table itself causes a blind spot of projection on the workpiece. (For example, the bottom of the workpiece, the shadow of the rotary table). Therefore, it is not possible to project uniformly on the processing surface of the workpiece, especially in the case of a complicated outer shape or a hollow casting using a core, the blind spot is increased, and there are many places where the projection is insufficient. Become.

  In order to eliminate the inconvenience of such a table type shot blasting apparatus, a hoist type shot blasting apparatus as described in JP-A-9-234671 is also known. In this apparatus, the workpiece is suspended by a plurality of chains, and the length of the chain is adjusted to perform shot blasting while tilting the suspended workpiece. For example, a long workpiece can be tilted in a suspended state by hanging both ends in the longitudinal direction with a pair of chains and adjusting the length of each chain. Therefore, the blind spot of projection is smaller than that of the table type shot blasting apparatus, and it is excellent in the quality of the cleaning.

  However, although the apparatus in the publication can tilt the suspended workpiece, it cannot be rotated completely in the suspended state (for example, around the longitudinal axis of the workpiece). Accordingly, with respect to a workpiece having a pocket portion such as a desired recess or depression on the processing surface, the projection material accumulates in the pocket portion, and the entire processing surface cannot be completely shot blasted. Furthermore, when the workpiece is long, in order to increase the freedom of tilting, it is necessary to make the height, width, and depth dimensions in the projection chamber longer than the long side of the workpiece. Further, when the workpiece is in a vertically long posture, the posture itself tends to make the workpiece unstable. Further, when the workpiece is in a horizontally long posture, the interval between the pair of chains that lock the end portions of the workpiece is widened, and the inclination angle of the chain is also increased. Therefore, a large load is applied to the sheave unit provided on the ceiling wall of the projection chamber in order to smoothly guide the chain to the wheel that drives the chain. Accordingly, the projecting material jumps out of the projection chamber due to wear of the sheave unit, so that the working environment may be deteriorated or the chain may be broken due to early wear. In the case where the workpiece is long, it is conventionally processed in a state where both ends in the longitudinal direction are suspended in consideration of the balance of the workpiece. In this case, both ends in the longitudinal direction are moved up and down to process the entire circumference of the workpiece. For example, if a long workpiece has a length of 5 m and a diameter of 0.2 m, in order to move both ends of the workpiece up and down, the projection chamber has a vertical movement amount of 5 m × length of 5 m × width of 0.2 m. is required. Accordingly, the volume of the projection chamber becomes relatively large, which is not preferable from the viewpoint of space saving.

  Accordingly, an object of the present invention is to provide a shot blasting apparatus that can improve the scouring quality, reduce the volume of the projection chamber, suppress the projection of the projection material, and is particularly suitable for shot blasting of large metal products. .

    An apparatus for shot blasting a workpiece according to the present invention comprises: a rail disposed above the shot blasting apparatus and extending in a horizontal direction; elevating means that travels along the rail and is movable up and down; Suspensions that are suspended from the means, each having an endless member that suspends and holds one or the other end of one workpiece, and a mechanism that feeds the endless member, so that both ends are held by the endless member. Two reversing machines that cooperate to rotate the workpiece in a reversible manner about an axis parallel to the extending direction of the rail; and having an inlet on one side and defining a projection chamber inside The upper surface of the enclosure is provided with an elongated opening extending in the extending direction from the inlet so as to form a passage for the endless member holding the workpiece. In the projection chamber, the workpiece held by the endless member inserted through the opening can be moved in the rail extension direction by running of the lifting means, and rotates around a rotation axis parallel to the extension direction. An enclosure having a possible volume; a projector disposed in the projection chamber and projecting a projection material; and projected by closing an opening provided on an upper surface of the enclosure through which an endless member is inserted. A sealing mechanism for preventing scattering from the opening of the projection material; and a projection material circulation means for collecting the projection material projected into the projection chamber and re-supplying it to the projector.

  The sealing mechanism preferably includes a sealing member that closes a region where the endless member does not exist in the opening in a state in which the lifting and lowering unit stops with the workpiece positioned at the projection position.

  According to the embodiment of the present invention, the sealing member is positioned in front of the preceding reversing machine out of the two reversing machines on the upper surface of the enclosure in a state where the lifting means is stopped by positioning the workpiece at the projection position. And a pair of first outer seals slidable along a direction intersecting the extending direction and a position corresponding to the rear position of the subsequent reversing machine, and 2 in the stopped state on the upper surface of the enclosure. And a second inner seal that is slidable in a direction intersecting the extending direction and disposed at a corresponding position between the turners of the table. In this case, it is preferable that the seal mechanism further includes a pair of third seals disposed at positions corresponding to the two reversing machines in the stopped state on the upper surface of the enclosure, respectively, Slidable in a direction crossing the extending direction and having a plurality of notches or gaps through which the endless member is inserted. According to an embodiment of the present invention, the third seal is also slidable in a direction along the extending direction.

  According to an embodiment of the present invention, the lifting means is one or two hoists adapted to raise and lower two reversing machines.

The above and other objects and advantages of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings.
FIG. 1 schematically shows a shot blasting apparatus according to an embodiment of the present invention. FIG. 2 is a front view of the shot blasting apparatus of FIG. 1 as viewed from the inlet side. FIG. 3 is a plan view of the projection chamber of the shot blasting apparatus of FIG. 1, and shows a sealing mechanism when the opening is open. FIG. 4 is a view similar to FIG. 3 except that the outer seal and the inner seal close the opening, and the endless member seal does not close the opening. FIG. 5 is a view similar to FIG. 4 except that the endless member seal is also shown with its opening closed. FIG. 6 is a view similar to FIG. 3, but showing a state in which the opened endless member seal has moved along the horizontal movement direction of the endless member.

  A horizontal rail 2 capable of supporting a load applied to the workpiece W is suspended on the upper portion of the shot blasting apparatus according to an embodiment of the present invention shown in FIGS. 1 to 3. It extends from above the work area S for winding and removing W to and from the chain sling 1 to above the enclosure B that defines the projection chamber 5.

  The rail 2 is provided with two hoists (lifting means) 3 that can run along the rail and can be lifted and lowered by, for example, a wire 31. A reversing machine 4 is suspended on the wire 31 of each hoist 3. The reversing machine 4 employs a chain sling 1 that forms an endless member by connecting both ends of the chain, and a mechanism that sends out the chain sling. The chain sling 1 has a length that can be at least partially wound around the peripheral surface of the workpiece W. The two reversing machines 4 cooperate so that one workpiece W held at both ends by the chain sling 1 is reversed, rotated forward and tilted in a suspended state. At one end of the enclosure B facing the work area S, an entrance for accessing the projection chamber 5 defined inside the enclosure B is provided. Further, the top plate 52 of the enclosure B that defines the upper surface of the projection chamber 5 has an elongated opening 51 extending from the entrance along the extending direction of the rail 2 so as to form a passage of the chain sling 1 on which the workpiece W is suspended. (FIGS. 2 and 3) are provided. The volume of the projection chamber 5 is such that the workpiece W held by the chain sling 1 can move in the extending direction of the rail 2 by the travel of the hoist 3 and is rotated around a rotation axis that is substantially parallel to the extending direction. Is an area that can be rotated.

  A plurality of projectors 7 for accelerating and projecting the projection material are installed in the projection chamber 5. A known projector can be used as the projector 7, and a centrifugal projector is used in this embodiment, but the projector is not limited to this. For example, when processing a limited peripheral surface of the entire circumference of a large workpiece, an air projector that accelerates and projects the projection material with air can be used.

  A projection material circulation system 8 is also installed in the projection chamber 5 to collect the projected projection material and supply it again to the projector. 1 and 2, the projection material circulation system 8 is installed in the lower part of the projection chamber 5, and an oscillating conveyor 81 that conveys the projection material dropped to the lower part of the projection chamber 5 in the horizontal direction, and the feed of the oscillating conveyor 81. And a bucket elevator 82 that conveys the projection material that has been horizontally fed to the upper side. A horizontal screw conveyor 84 is installed in the vicinity of the discharge port 83 for discharging the projection material at the upper part of the bucket elevator 82 so as to receive the discharged projection material, and a plurality of projection material outlets 84a are provided in this. . A hopper 85 for storing the projection material is disposed below the projection material outlet 84a, and a first pipe 86 communicates with the bottom of the hopper 85. The first pipe 86 is provided with a cut gate 87 that opens and closes the first pipe 86 so as to adjust the flow rate of the projection material. The bottom of the cut gate 87 communicates with the projection material supply port of the projector. A second pipe 88 is provided.

  A sealing mechanism 6 that seals the projection chamber 5 is provided on the top plate 52 of the projection chamber 5 so that the projected projection material does not scatter from the opening 51 to the outside of the projection chamber 5. The seal mechanism 6 does not obstruct the movement or rotation of the chain sling 1 inserted through the seal mechanism 6 and prevents the projection material from jumping out from the opening 51 of the projection chamber 5 or preventing dust from being blown out. It is configured to have a plurality of notches or gaps that are inserted in the direction. For example, an elastic body such as a rubber plate having a plurality of cuts that can be inserted through the chain sling 1 positioned in the opening 51 in a lateral direction is stacked in a single layer or multiple layers, and the chain sling 1 along the extending direction of the rail 2 is The moving path H in the horizontal direction (see FIG. 3, the hoist 3 is not shown in FIG. 3, but this moving path H corresponds to the moving locus of the hoist 3) can be associated. However, the present invention is not limited to this. Alternatively, it may be a bundled resin wire or metal wire, or a brush-shaped elastic body formed from a resin plate, sponge, or cloth brush. A chain sling 1 positioned in the opening 51 is inserted in the gap between the brush teeth in the lateral direction.

  However, the region where the chain sling 1 is not positioned during projection in the opening 51 can be simply closed without considering the presence of the chain sling 1. Therefore, in order to seal such a region, it is preferable to employ a rigid material, for example, a steel plate, in order to improve the wear resistance and blowing prevention performance of the seal mechanism 6. The area that can be closed without considering the presence of the chain sling 1 during the projection at the opening 51 is a state in which the hoist 3 is stopped with the workpiece W positioned at the projection position in the projection chamber 5 and the two are reversed. It is an area in front of the preceding inverter 4 among the machines 4, an area behind the succeeding inverter 4, and an area between the two inverters 4. Therefore, the seal mechanism in the embodiment of FIGS. 2 and 3 includes a pair of first outer seal 61 and second inner seal 62, which are made of steel plates.

  The pair of first outer seals 61 is the preceding reversing machine 4 of the two reversing machines 4 on the top plate 52 in a state where the hoist 3 stops the workpiece W at the projection position in the projection chamber 5. Are disposed at positions corresponding to the front position of the rear and the rear position of the succeeding reversing machine 4. Each first outer seal 61 is provided with a slide mechanism, for example, an air cylinder 61a, and can slide in a direction V intersecting the movement path H by expansion and contraction of the air cylinder 61a. The second inner seal 62 is also a steel plate, and is disposed on the top plate 52 of the projection chamber 5 main body at an intermediate position between the two reversing machines 4 when the hoist 3 is stopped at the projection position of the workpiece W. A slide mechanism, for example, an air cylinder 62a, is attached to the second inner seal 62, and can slide in a direction V that intersects the movement path H by expansion and contraction of the air cylinder 62a. In a peripheral portion where the first seal 61 and the second seal 62 overlap, a sealed portion (not shown) is formed to prevent the projected projection material from leaking out.

  When the seal mechanism 6 includes the pair of the first outer seal 61 and the second inner seal 62 as described above, in the region between the outer seal 61 and the second inner seal 62 in the opening 51, In this way, the chain sling 1 is inserted. This configuration is shown as a pair of third seals 63 through which the chain sling 1 is inserted in the embodiment of FIGS. Each of the third seals 63 is basically made of a steel plate, but is elastic such as a rubber plate stacked in a single layer or multiple layers having a plurality of cuts as described above so as not to hinder the movement and rotation of the chain sling 1. A sealed portion 6S made of a body is formed. When workpieces W of various dimensions are processed, and the position of the two reversing machines 4 and thus the position of the chain sling 1 during projection change depending on the workpiece W to be processed due to the difference in dimensions. 2 and 3, the pair of third seals 63 are not only in the direction V intersecting the movement path H of the chain sling 1, but also in the direction along the movement path H of the chain sling 1 (of the hoist 3). It is preferable that it can slide also in the traveling direction). The pair of third seals 63 are provided on the top plate 52 of the projection chamber 5 main body at positions corresponding to the two reversing machines 4 in a state where the hoist 3 is stopped at the projection position of the workpiece W. The third seal 63 includes a slide mechanism, for example, an air cylinder 63a, and a drive motor 63b that adjusts the distance between the pair of third seals 63. The third seal 63 slides in the direction V intersecting the movement path H by the expansion and contraction of the air cylinder 63a, and slides in the same direction as the movement path H by the drive motor 63b. The third seal 63 is formed with a U-shaped notch 63U through which the chain sling 1 is inserted in the lateral direction. Preferably, the hoist 3 is provided with a position detection sensor (not shown) for detecting the position of the chain sling 1. By sliding the third seal 63 so that the position of the chain sling 1 detected by the position detection sensor and the U-shaped notch 63U of the third seal 63 are aligned, the chain sling 1 is moved to the U-shaped notch 63U. Is inserted horizontally.

  A pair of first (outer) seals 61, a second (inner) seal 62, and a pair of third seals 63 through which the chain sling 1 is inserted, on each side of the steel plate, the liner having wear resistance May be provided.

  In the illustrated embodiment, two hoists 3 are used, but only one hoist may be used as long as the interval between the two reversing machines 4 can be fixed or variable. When the interval between the two reversing machines 4 is made variable by one hoist, a mechanism for making the interval between the two reversing machines 4 variable, for example, a support frame having an air cylinder is suspended from the hoist. By supporting the two reversing machines 4 on the support frame, the interval between the two reversing machines 4 can be made variable. The one or two hoists can be, for example, an electric wire hoist or an electric chain block hoist, but are not limited thereto. As an alternative lifting means, a hydraulic cylinder or a servo cylinder may be used instead of the hoist.

  The reversing machine 4 is not limited to the illustrated form, and any reversing machine 4 may be used as long as it has an annular endless member and a mechanism for feeding the endless member. As the endless member, instead of the chain sling 1, other configurations are possible in which both ends are connected to form an annular shape and can be at least partially wound around the peripheral surface of the workpiece W, such as a sling belt or a ring wire. Good.

  Each slide mechanism is retracted from the opening 51 while the workpiece W is moving, and is in close contact with the opening 51 during projection. Instead of the slide mechanism, a door mechanism having a rotation link may be used. The drive source of such a slide mechanism or door mechanism may be a hydraulic cylinder, a rotary cylinder, a servo cylinder, or a motor instead of the air cylinder of the illustrated embodiment. For example, a slide mechanism can be configured by combining a rack and pinion mechanism with a motor.

  The projection material circulation system 8 uses, as an example, an oscillating conveyor 81, a bucket elevator 82, and a screw conveyor 84. However, depending on the size of the projection chamber 5 and the layout of the installation factory, the projection material is transported and separated from the foundry sand. It is good also as other composition which can remove dust.

  The operation of the shot blasting apparatus according to the embodiment of the present invention will be described based on a processing example for removing the foundry sand of the cast product as the workpiece W. This processing example is an example for explaining the operation of the shot blasting apparatus of the present invention, and does not limit the present invention.

Processing conditions As the workpiece W, a machining center column for machine tools made of cast iron having a length of 4000 mm, a width of 2000 mm, and a thickness of 450 mm was used. The projection chamber 5 in the shot blasting apparatus has a length of 8000 mm, a width of 5000 mm, and a height of 6500 mm. Eight centrifugal projectors 7 are installed on the side surface of the projection chamber 5, and the projection material used is a steel shot having a particle diameter of 2.5 mm. The projection process was performed at a projection speed of 70 m / s and a projection amount of 150 kg / min per centrifugal projector 7. Two hoists 3 having a maximum lifting load of 12 tons were used for conveying the workpiece W, and the maximum hoisting speed was 8 m / min and the maximum traveling speed was 10 m / min. As the reversing machine 4, a chain sling type reversing machine (manufactured by Nippon Hoist Co., Ltd. (Hiroshima)) was used, and two machines having a maximum lifting load of 10 tons were used. Here, the length of the chain sling was 12 m, and the chain sling feed speed was 4 m / min at the maximum.

Operation The workpiece W is suspended in the work area S with the chain sling 1 wound around it. After the workpiece W is suspended, the hoist 3 moves along the rail 2, and the workpiece W moves from the loading / unloading door installed on the end face of the projection chamber 5 into the projection chamber 5. After the workpiece W has moved to the projection position, the chain sling 1 of the reversing machine 4 is sent, and the workpiece W rotates at a constant speed. At the same time, a pair of first (outer) seal 61 and second (inner) seal 62 slide to cover the opening 51, and then the third (endless member) seal 63 is fitted to the hoist 3 in accordance with the position of the chain sling 1. After moving along the direction of the movement trajectory, the sliding to the opening 51, the chain sling 1 is sandwiched by the U-shaped notch 63U of the third seal 63, the entire surface of the opening 51 is shielded by each seal. After the shielding of the opening 51 is completed, the centrifugal projector 7 is activated and the projection material is projected into the projection chamber 5.

  During the projection process, the workpiece W rotates for a certain time, and then a part having a complicated shape and a long processing time stops at a position where the projection amount is large. After stopping for a certain time, the workpiece W rotates for a certain time in the opposite direction. During the projection process, the rotation, stop, inversion, and stop of the workpiece W are repeated in this way. In addition, in the workpiece W having a shape in which the projecting material easily collects in the pocket portion, the stopping process may be replaced with forward deceleration or reverse deceleration.

  In this embodiment, the projection time is 15 minutes in total. After the projection is finished, the workpiece W is rotated for a certain period of time, and the rotation is stopped after dropping the projection material attached thereto. Next, each seal that has shielded the opening 51 is slid in a direction to open the opening 51. Thereafter, the hoist 3 moves along the rail 2, and after the workpiece W reaches the work area S, the hoist 3 is removed from the chain sling 1 and the process ends. It was observed that the entire surface of the workpiece W after the projection processing was uniformly projected, and the polishing quality was good.

  According to the shot blasting apparatus of the present invention, the chain sling 1 of the reversing machine 4 is wound around the workpiece W, and the workpiece W in a suspended state is rotated around its horizontal axis by driving the reversing machine 4. The pocket portion of the workpiece W can be turned downward, and the projection material accumulated therein can be discharged, so that the inside of the pocket portion requiring processing can be exposed. Furthermore, since the workpiece W in a suspended state rotates, the entire circumference can be processed. Therefore, regardless of the position of the pocket on the circumferential surface of the workpiece W, the projection material is appropriately discharged. And there is no accumulation of projection material on the workpiece W. Therefore, the polishing quality can be improved by exposing the processing surface of the workpiece W periodically and projecting the entire surface of the workpiece W evenly. Furthermore, scattering of the projection material can be reduced by the seal mechanism 6. Further, since the workpiece W can be held in a stable posture by the chain ring 1, an accidental fall of the workpiece W can be prevented.

  The movement of the workpiece W is a movement along the extending direction of the rail 2 and a rotation around the horizontal axis of the workpiece held in a suspended state by the endless member 1. Therefore, even if the workpiece W is long, the volume of the projection chamber 5 does not need to be excessively increased by aligning the longitudinal direction with the extending direction of the rail 2. Therefore, it is possible to design to reduce the volume of the projection chamber 5 for the purpose of saving space. For example, in order to process a long workpiece having a length of 5 m × diameter of 0.2 m, a conventional apparatus required a projection chamber having a vertical movement amount of 5 m × length of 5 m × width of 0.2 m. In the shot blasting apparatus of the present invention, since the workpiece is rotated around the longitudinal direction of the workpiece, the volume of the projection chamber 5 can be 0.2 m long × 5 m long × 0.2 m wide.

  Applications suitable for the shot blasting apparatus of the present invention are not limited to the following, but include, for example, an upper die of a press die, a lower die holder, a lathe bed for a machine tool, a machining center column, a sheet metal processing machine frame, and an industrial Large size (for example, a weight exceeding 1 ton) such as a suction casing for machinery, a gear reducer case, a cast iron pipe having a nominal diameter of 500 mm or more, a spiral casing for a compressor, and a housing housing a reducer. It is a shot blasting treatment for removing foundry sand of a cast product. Furthermore, the shot blasting apparatus of the present invention is not limited to the following, but is a frame structure, a mold, and the like that are joined to a predetermined shape by welding parts used for a large welded structure such as a bridge, shipbuilding, steel tower, etc. It is also suitable for shot blasting for purposes such as removing the scale after heat treatment of steel, etc., adjusting the substrate before painting, and surface roughening to improve the surface friction coefficient.

  While specific embodiments and alternatives thereof have been described above with specific dimensions, these embodiments and dimensions are for illustrative purposes and are not intended to be limiting. Please keep in mind. It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described embodiments and dimensions without departing from the spirit of the invention as defined in the appended claims.

Claims (5)

An apparatus for shot blasting a workpiece,
A rail disposed above the shot blasting device and extending horizontally;
Elevating means that travels along this rail and that can be moved up and down;
An annular endless member suspended from the elevating means and each of which is wound at least partially around the peripheral surface of one or the other end of one workpiece, And a mechanism for feeding the member to cooperate with each other so as to rotate the work piece in a suspended state, both ends of which are held by the endless member, reversibly about an axis parallel to the extending direction of the rail. A reversing machine,
An enclosure having an entrance on one side and defining a projection chamber inside, and an upper surface of the enclosure in the extending direction from the entrance so as to form a passage for the endless member holding a workpiece An elongated opening extending along the projection chamber, the workpiece being held by the endless member inserted through the opening is movable in the extending direction of the rail by the travel of the lifting means; and An enclosure having a volume rotatable about a rotation axis parallel to the extending direction;
A projector that is disposed in the projection chamber and projects a projection material;
A sealing mechanism that is provided on the upper surface of the enclosure and prevents the projected projection material from scattering from the opening by closing the opening through which the endless member is inserted;
The projection material projected into the projection chamber is collected, and provided with a projection material circulation means for re-supplying the projection material,
The seal mechanism includes a seal member that closes a region where the endless member does not exist in the opening in a state in which the elevating unit stops with the workpiece positioned at the projection position, and the seal member extends in the extending direction. A shot blasting device that is slidable along the intersecting direction. The shot blasting apparatus according to claim 1, wherein the seal member is
In the state where the lifting means stops with the workpiece positioned at the projection position, the front surface of the preceding reversing machine of the two reversing machines and the rear position of the succeeding reversing machine on the upper surface of the enclosure. A pair of first outer seals disposed at corresponding positions and slidable along a direction intersecting the extending direction;
A shot blasting apparatus including a second inner seal slidable in a direction crossing the extending direction, disposed on a top surface of the enclosure at a corresponding position between the two reversing machines in the stopped state. . 3. The shot blasting apparatus according to claim 2, wherein the seal mechanism further includes a pair of third seals disposed on the upper surface of the enclosure at positions corresponding to the two reversing machines in the stopped state, The third seal is slidable in a direction crossing the extending direction, and has a plurality of notches or gaps through which the endless member is inserted. 4. The shot blasting apparatus according to claim 3 , wherein the third seal is slidable in a direction along the extending direction. 2. The shot blasting apparatus according to claim 1, wherein the lifting means is one or two hoists adapted to lift and lower the two reversing machines.

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