JP4586419B2 - Centrifugal barrel polishing equipment - Google Patents

Description

  The present invention relates to a centrifugal barrel polishing apparatus and a centrifugal barrel polishing method including a plurality of polishing tanks that revolve simultaneously with rotation. In particular, the present invention relates to a novel centrifugal barrel polishing apparatus suitable for heavy cutting by wet centrifugal barrel polishing.

  The barrel polishing apparatus includes a centrifugal type, a fluid type, a vibration type, and a rotary type. Among these, centrifugal barrel polishing has the largest polishing power. Centrifugal barrel polishing includes both wet and dry methods, but in general, wet methods can provide stronger polishing power than dry methods.

  In wet centrifugal barrel polishing, it is common to perform barrel polishing by putting a work (object to be polished) into a polishing tank together with media, compound and water. So-called co-grinding polishing in which a polishing aid (for example, alumina fine powder) is added and mixed is also performed.

  In any of the above cases, heat is generated by the friction between the workpiece and the medium or between the workpieces, and the internal pressure increases as the polishing tank becomes hot. This tendency becomes prominent when driving for a long time.

  However, as far as the inventors know, in a centrifugal barrel polishing apparatus provided with a plurality of polishing tanks that revolve simultaneously with rotation, those equipped with a mechanism that suppresses an increase in internal pressure as the polishing tank becomes hot. Not known.

  Patent Document 1 is a prior art for performing barrel polishing of ceramic parts while cooling a polishing tank by means such as water spraying in wet centrifugal barrel polishing.

  The wet centrifugal barrel polishing in this document does not include an exhaust mechanism (exhaust means) and is different from the wet barrel polishing of the present invention, and does not affect the inventiveness of the present invention.

  Further, in a dry centrifugal barrel polishing method in which a plurality of barrel pots revolve and dry-polish an object to be polished by a dry medium flowing in each barrel pot, the interior of each barrel pot is collected by a dust collector connected to each barrel pot. Patent Document 2 discloses a technique for collecting outside air into the mass, allowing the outside air to pass through the mass, and sucking and collecting the dust generated in the mass and cooling the mass.

The barrel pot in this document is not equipped with a ventilation means in the direction of the rotation axis of the polishing tank and further a cooling mechanism (cooling means) as an exhaust mechanism, as in the present invention. It has no effect.

  In view of the above, the object of the present invention is to provide a novel centrifugal barrel polishing capable of suppressing an increase in internal pressure as the polishing bath becomes hot and simultaneously cleaning and rust-proofing the workpiece in the polishing bath after polishing. To provide an apparatus.

  The centrifugal barrel type barrel polishing apparatus of the present invention has made extensive efforts to solve the above problems, and as a result, with the following configuration, it is possible to suppress an increase in internal pressure as the polishing tank becomes hot, and it can be operated continuously for a long time. As a result, the inventors have conceived the present invention having the following constitution.

In a centrifugal barrel polishing apparatus provided with a plurality of polishing tanks that rotate and revolve, the polishing tank is provided with ventilation means in the direction of the axis of rotation of the polishing tank and external cooling means as appropriate.

  In the polishing apparatus of the present invention, even in extremely severe heavy grinding polishing (the temperature in the polishing tank rises and gas is generated accordingly), the aeration means (supply / exhaust) can The gas generated in the process can be exhausted to the outside of the polishing tank at all times during polishing, and external cold air can be supplied into the polishing tank during polishing, or intermittently or continuously on the surface of the polishing tank. The temperature rise in the polishing tank can be suppressed by spraying water.

  Therefore, even during long-time polishing, there is no need to stop the operation of the apparatus during the polishing, and to cool or vent the gas.Furthermore, after the polishing, the cleaning water is supplied from the air supply port with the polishing tank lid closed. It is possible to remove the product after supplying water and washing the workpiece, and then injecting a rust preventive by the same method until the rust prevention treatment is performed.

  In the above apparatus, the ventilation means of the polishing tank is provided with a ventilation hole at the central position of at least one side plate part of the cylindrical body part having an open / close lid or in the vicinity thereof, and the ventilation hole is provided in the polishing tank. Further, it is possible to provide a configuration in which a gas piping for supplying cooling gas and / or exhausting pressure gas generated in the polishing tank is connected.

  Similarly, as a cooling means of the polishing tank, the material of the body part and the side plate part of the polishing tank is made of a member having high thermal conductivity, and the outer peripheral surface of the body part has high thermal conductivity and / or liquid retention. The cooling liquid spraying means may be arranged so that the cooling liquid is sprayed to the heat exchange medium of the polishing tank that rotates and revolves during polishing while coating the heat exchange medium composed of the members.

  As a means for cooling the polishing tank, the material of the body and side plates of the polishing tank is made of a material having high thermal conductivity, a coolant passage is formed in the body, and one of the coolant passages is formed. It can also be set as the structure which connected the drainage channel to the water supply path and the other, respectively.

  In the centrifugal barrel polishing apparatus having each configuration described above, at least one of the wear-resistant liners provided on the inner surfaces of the body portion and the side plate portion of the polishing tank in a replaceable manner is a member having a high thermal conductivity. It is desirable to make it. By setting it as a member with high heat conductivity, heat dissipation is accelerated | stimulated from the surrounding wall of a tank body, and the cooling efficiency of a to-be-polished object improves.

  In the centrifugal barrel polishing apparatus having the above-described configuration, it is desirable that a ventilation means is provided in the cabinet body that houses the plurality of polishing tanks, and a mist collector is connected to the ventilation means.

  And it is desirable to apply the centrifugal barrel polishing apparatus having the above-mentioned configurations to those having the following configurations.

A rotating disk integrally rotating with a revolving shaft connected to a rotation drive source; a plurality of polishing tanks pivotally supported on the rotating disk via a rotating shaft; and connected between the revolving shaft and the rotating shaft A centrifugal barrel polishing apparatus provided with planetary rotating means for revolving and rotating each polishing tank,
The axis of rotation axis of each polishing tank is parallel or inclined with respect to the axis of revolution axis of the rotating disk,
The planetary rotating means is characterized in that the rotation direction of each polishing tank is opposite to the revolution direction, and the rotation / revolution speed ratio is the former / the latter = 1/1 to 2.5 / 1. To do.

  In the above, it is desirable that the axis of the rotation axis of each polishing tank is inclined with respect to the axis of the revolution axis of the rotating disk, particularly 5 to 15 °. This is because uniform polishing is possible.

  The centrifugal polishing method according to the present invention using the apparatus of the present invention has the following configuration.

A method of barrel-polishing a metal workpiece using a centrifugal barrel polishing apparatus having a plurality of polishing tanks that rotate and revolve,
The inside of the polishing tank is polished while ventilating in the direction of the rotation axis of the polishing tank and appropriately cooling.

  In the first place, in the centrifugal barrel polishing of iron-based workpieces, the present inventors generated hydrogen gas and polished the increased internal pressure of the polishing tank by ventilation (air supply / exhaust), and the gas in the polishing tank (barrel) The inventors have found that generation is suppressed and have arrived at the present invention. That is, the workpiece is scraped by the fine abrasive material due to a strong pressure during polishing, and a lot of iron fine powder is generated. At this time, a large amount of frictional heat is generated and the temperature rises. In addition, iron fine powder acts to decompose water into hydrogen and oxygen, increasing the internal pressure. However, gas generation is also suppressed by suppressing an increase in the temperature in the tank by appropriate external cooling. At this time, oxygen generated simultaneously with hydrogen reacts with iron fine powder and is consumed as iron hydroxide or iron oxide, and the gas in the polishing tank is mostly hydrogen.

  Further, the centrifugal barrel polishing method of the present invention is a method in which the workpiece is put into the polishing tank together with the processing liquid and the fine abrasive powder, and then the polishing liquid is sprayed intermittently or continuously on the outer surface of the body of the polishing tank. It is configured to ventilate the gas generated in the tank.

  In heavy grinding and polishing with a large amount of grinding and polishing, one-step barrel polishing cannot be used. If you try to do it in one step, it is necessary to stop the machine on the way, exhaust it once for degassing or cooling, wash it, wash it again, insert media, compound, water again and polish it .

  However, in the present invention, the edge polishing of the workpiece can be performed in one step as shown in the examples described later by so-called co-grinding in which the polishing is performed substantially only by the workpiece without using the medium.

  The reason is that even if the temperature in the polishing tank rises due to the polishing of the workpiece and gas is generated along with it, 1) The gas generated in the polishing tank is being polished by the ventilation means (supply / exhaust) In addition, it can be exhausted to the outside of the polishing tank at all times, and 2) externally cooled air is supplied into the polishing tank during polishing, or water is sprayed intermittently or continuously on the surface of the polishing tank. This is because the temperature rise in the polishing tank can be suppressed.

  In addition, since no media is used, when a wet polishing barrel apparatus having the same capacity (same capacity) is used, the processing amount per polishing tank is significantly increased.

  In the above-described configuration, it is desirable that ventilation is performed by an exhaust port formed in the approximate center of one side wall of the polishing tank or in the vicinity thereof. In centrifugal barrel polishing, the workpiece is pressed against the inner wall of the polishing tank by centrifugal force during operation, and the workpiece and water are not present in the central portion, and there is no possibility of flowing out of the central hole.

  It is desirable that the ventilation be further performed by the combined use of air supplied from an air supply port formed at or near the center of the opposing wall of the one side wall where the exhaust port is formed. Ventilation can be performed efficiently and cooling of the polishing tank by supplying air can be performed efficiently.

  Further, as the polishing tank, the body part and the side plate part of the polishing tank are formed of a member having a high thermal conductivity, and the outer peripheral surface of the body part is a heat made of a member having a high thermal conductivity and / or a liquid retention rate. It is desirable to use a coating with an exchange medium. Improvement of the polishing tank cooling efficiency when the coolant is sprayed can be expected.

  Each of the polishing tanks has a rotation direction opposite to the revolution direction, and the rotation ratio of rotation to revolution is such that the former / the latter (rotation ratio) ≈1 / 1 to 2.5 / 1. It is desirable to operate by rotating and revolving the polishing tank.

  The frequency of frictional flow between the workpieces increases due to the complex flow of the machining fluid, and the polishing ability due to the mutual sliding of the workpieces increases. In addition, by setting the rotation ratio to about 1.5 / 1 to 2.5 / 1, it is possible to further improve the polishing ability.

  Further, it is desirable that the axis of the rotation axis of each polishing tank is inclined with respect to the axis of the revolution axis to rotate and revolve each of the polishing tanks, and the inclination angle is preferably 5 to 15 °. The reciprocating movement of the workpiece in the axial direction is frequent, and as described above, the polishing ability by the mutual sliding of the workpieces is increased and uniform polishing is possible.

  In each of the above-mentioned configurations, it is desirable to use one or two or more selected from the group of alumina oxide, silicon carbide, and zirconia as the fine powder abrasive. These have a greater polishing force than in normal use.

In the centrifugal barrel polishing method, the work after the polishing is finished, while rotating the polishing tank , the one air supply port for ventilation in the rotation axis direction of the polishing tank is used as the liquid supply port, and the other The cleaning tank and the workpiece can be cleaned by passing the cleaning liquid through the exhaust port as a liquid discharge port.

  At this time, since the cleaning liquid is supplied while the lid of the polishing tank is closed, the sewage is discharged from one liquid discharge port, and the cleaning liquid does not scatter. Further, by passing the cleaning liquid (tap water), the inside of the polishing tank is cooled until the cleaning is completed.

  Each polishing tank at this time can be cleaned while changing the positional relationship of each polishing tank intermittently by performing a partial revolution of less than one revolution, or by continuously rotating at a low speed without generating centrifugal force. desirable. There is no difference in the amount of water passing through each polishing tank based on the head due to the tap water pressure, and there is no difference in the cleaning level in each polishing tank.

  And after completion | finish of washing | cleaning, the inside of a grinding | polishing tank is a washing | cleaning liquid remaining state, Furthermore, after supplying a rust preventive agent from a liquid supply port, the said grinding | polishing tank can be rotated and a rust prevention process can be given to a product.

  In this way, after the rust prevention treatment is performed, the mass is discharged, so as compared with the case of discharging at a high temperature as in the past, the scattering of sewage, the safety of the worker, the ease of precision cleaning in the subsequent process, It has an excellent effect in terms of rust prevention treatment of workpieces.

The rotation speed of the polishing tank in the above cleaning or rust prevention treatment is usually appropriately set in the range of 10 to 30 min ^{−1 in} order to appropriately rotate the work in the tank and increase the cleaning efficiency.

  1 to 4 show an embodiment of the present invention.

  As shown in FIG. 1, a rotating disk 16 that rotates integrally with a revolving shaft 14 that is connected to a rotation drive source (prime motor) 12; a rotating shaft 18 is provided between the rotating disks 16 and 16 at the periphery of the revolving shaft 14. A plurality of (four in the illustrated example) polishing tanks 20 that are pivotally supported; and planetary rotating means 32 that are connected between the revolution shaft 14 and the rotation shaft 18 and rotate each of the polishing tanks 20. .

  Specifically, it is as follows.

  The rotation drive source (prime mover) 12 including the prime mover (electric motor: motor) 12 and the revolving shaft 14 are connected through the two-stage deceleration of the first-stage driven pulley 26 and the second-stage driven pulley 28 from the rotation drive source 12. ing. As shown in FIG. 2, the revolving shaft 14 is connected to both side walls 24a of the cabinet via revolving shaft bearings 25, 25 attached to the opposite sides of the both side walls 24a, 24a of the polishing apparatus box (cabinet). 24a is supported. Here, the transmission means 30 and 30A for driving the revolving shaft 14 from the prime mover 12 are usually belt conduction, but other transmission means (transmission device) such as chain conduction and gear transmission may be used. Good.

  The rotation shafts 18, 18 are attached to the rotation disks 16, 16 via rotation shaft bearings 19, 19 attached to the outside of the rotation disks 16, 16. In this embodiment, the planetary rotating means is a planetary gear device 32 including a sun gear 34 and a planetary gear 36. The sun gear 34 is attached to the revolution shaft 14 outside the rotating disk 16, and the planetary gear 36 is attached to the rotation shaft 18.

  In the planetary gear device 32, the rotation direction is opposite to the revolution direction. This is because when the rotation direction and the revolution direction are the same direction, the mass (workpiece and abrasive) in the polishing tank is less likely to be disturbed and the polishing power is reduced. Moreover, the rotation speed ratio between rotation and revolution (the former / the latter: rotation ratio) can be set as appropriate within a range of about 1/1 to 2.5 / 1. In the centrifugal barrel polishing apparatus, the rotation ratio is usually 1/1. However, in the so-called heavy grinding polishing that requires a high grinding rate, the rotation rate is high, for example, 1.5 / 1 to 2.5 / 1, especially about 2/1, the polishing power increases. Can be expected. Further, when the rotation ratio is increased and the axis of the rotation axis is inclined with respect to the revolution axis as will be described later, improvement in polishing uniformity can be expected.

  In this embodiment, each polishing tank 20 may be directly attached to the tip of the rotation shafts 18 and 18 as in the embodiments described later. However, in this embodiment, a pair of the exhaust tanks 20 is opened to open the exhaust port 67 in the cabinet. The mounting blocks 22a and 22b and the mounting frame 22c are used for mounting. When the polishing tank is small, it is also possible to support the polishing tank with a cantilever on the rotating shaft by using one rotating disk.

  Here, the axis of the rotation axis 18 of each polishing tank 20 may be parallel to the axis of the revolution axis 14 of the rotating disk 16 but is inclined. Since the axis L of the polishing tank 20 is inclined, improvement in polishing uniformity can be expected. At this time, the inclination angle α is preferably about 5 to 15 °, more preferably about 10 °. If the inclination angle is larger than 15 °, the supply port and / or the exhaust port may be closed by the mass, or the input liquid may flow out.

  Of course, a wire mesh can be provided at the air supply port 57 or the exhaust port 67 to reliably prevent the internal workpiece from jumping out or flowing out.

  Further, in the present embodiment, a ventilation duct (ventilating means) 40 is connected to an apparatus box (cabinet) 24 that houses the polishing tank 20, and the ventilation duct 40 is connected to a mist collector 42 (see FIG. 1). The cabinet 24 according to the present embodiment is provided with a mist collector 42 for collecting mist generated when the cooling water is sprayed intermittently on the surface of the polishing tank and hydrogen gas generated during polishing.

  The polishing tank 20 is provided with axial ventilation means and cooling means.

  The polishing tank 20 is a cylindrical body having a hexagonal cross section, and includes a mass loading / discharging port 20a. The mass loading / discharging port 20a includes an opening / closing lid 21 that is opened and closed by a cam lever (follower) 38. . A liner layer 74 is formed on the lower surface of the opening / closing lid 21, and a rubber packing 75 is attached to the peripheral contact surface. The cross-sectional shape of the polishing tank 20 is not limited to a hexagon, but may be a polygon such as a pentagon or an octagon, or a circle.

  In this embodiment, the ventilation means (air supply means) is a main supply passage 54 formed in the axial direction in the revolution shaft 14, and a branch connection 4 at a position before the rotary disk 16 from the main supply passage 54. Each branch air supply pipe 56 is connected to each branch air supply pipe 56, and is formed by a sub air supply passage 58 that is formed in the rotation shaft 18 and serves as an air supply port 57 at a position facing the polishing tank 20. Yes. Naturally, the main air supply passage in the revolution shaft 14 is connected to the external air supply pipe 62 via the main rotary joint 60 attached to one end side of the revolution shaft 14 so that the polishing tank 20 can revolve and rotate. . In addition, the base part side is connected to the external air supply piping 62 with the pneumatic transport machine (for example, compressor) which is not shown in figure. The auxiliary air supply passage 58 of the rotation shaft 18 is connected to the branch supply air pipe 56 via an auxiliary rotary joint (rotary elbow in the illustrated example) 64 attached to the tip of the rotation shaft 18.

  And in this embodiment, the exhaust means provides the exhaust port 67 in the center part (or its vicinity) of the side plate 20d of the polishing tank 20 facing the air supply port 57 formed in the side plate 20c. is there. This is to ensure the axial ventilation. Note that the air supply / exhaust port pair provided at the opposite position of both side plates so that an air flow is likely to be generated along the axis of the polishing tank 20 is at or near the axis as in this embodiment.

  The cooling means in the present embodiment is made of a member having a high thermal conductivity and / or water retention rate, and a cooling water (cooling) for the heat exchange medium 68 that covers the outer peripheral surface of the body portion 52a and the heat exchange medium 68. The cooling liquid spraying means 70 is arranged so as to spray the liquid). Here, the polishing tank (body portion and side plate portion) 52 is formed of a member having high thermal conductivity. In addition, the heat exchange medium 68 is appropriately exchangeable.

  Here, examples of the high thermal conductivity member forming the main body of the polishing bath 52 include iron alloy (steel), aluminum alloy, and copper alloy metal members. The thermal conductivity (20 ° C.) of iron is 0.17 cal / (s · m · ° C.) [0.714 W / (m · ° C.)]. In the present embodiment, a bellows-like fin 72 is formed on the body portion of the polishing tank main body 52 as shown in the figure in order to increase the contact area with the heat exchange medium. A short fiber flocking layer 68 is formed on the bellows-like fin 72. In addition, the bellows-like fins 72 may not be provided on the body portion 52a of the tank body 52, and the flat body may be covered with a short fiber flocking layer having a liquid retaining property and heat resistance, a towel cloth, or the like.

  Further, the inner liner layer 74 may be formed of a wear-resistant rubber member as in the conventional case, but is preferably formed of a wear-resistant iron-based alloy (for example, high chromium cast iron) having a good heat transfer coefficient. . Further improvement in cooling performance can be expected.

  In addition, the coolant spraying means 70 is normally formed by the shower part 71a which consists of a some nozzle in the front-end | tip part of the water supply branch piping 71 directly connected with the tap water. Note that it is possible to use a coolant having a larger latent heat of vaporization than water.

  Next, a polishing method using the polishing apparatus of the above embodiment will be described.

  First, in a state where the planetary rotating means is operated so that the polishing tank 20 is positioned so that the opening / closing lid 21 is on the upper side, the opening / closing lid 21 of the polishing tank 20 is opened by a cam operation, and the object to be polished and the compound are mixed with water. The lid 21 is closed. Thereafter, the rotary drive source 12 is driven, and the valve of the external air supply pipe 62 and the valve of the water supply pipe 69 are opened.

  Then, since the ventilation is performed in the axial direction in the polishing tank 20 that rotates and revolves, the gas generated in the polishing tank 20 is positively exhausted to the outside, and the generated heat is also taken away by water cooling. Thus, the temperature rise of the object to be polished is suppressed. For this reason, it is not necessary to stop the operation of the polishing apparatus due to gas exhaust during polishing, and after the polishing process is completed, it is washed with water and rusted as it is, and the open / close lid 21 is opened to take out the processed product. be able to. At this time, the polishing tank 20 is positioned so that the opening / closing lid 21 is positioned on the lower side, and the contents (product, finished product) are taken out by falling under its own weight.

  FIG. 5 shows a closed system instead of an open system in the above embodiment. Unlike the above, the planetary gear means is located inside the branch air supply / exhaust pipe. This is an appropriate design matter. Further, the rotary joints 64 </ b> A and 64 </ b> A to which both rotation shafts are connected are T-junction type in which the passage is sealed by the gland packing 65. In addition, the same or corresponding parts as those of the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted in whole or in part.

  That is, the exhaust means includes a main exhaust passage formed in the axial direction in the revolution shaft, four branch supply air 56 collectively connected to the main exhaust passage at a position in front of the rotating disk, and each collective exhaust pipe 76. It is formed by a sub exhaust passage 78 which is connected and formed in the rotation shaft 18 and which becomes the exhaust port 66 at a position facing the polishing tank 20. Naturally, the main exhaust passage in the revolution shaft is connected to an external exhaust pipe via a rotary joint attached to one end side of the revolution shaft, although not shown so that the polishing tank 20 can revolve and rotate. Further, the auxiliary exhaust passage 78 of the rotation shaft 18 is connected to the branch exhaust pipe via the auxiliary rotary joint (second) 64B attached to the tip of the rotation shaft 18. In the present embodiment, the ventilation into the polishing tank 20 may be a supply ventilation (air supply) for sending compressed air, as in the case of the above embodiment, but the main exhaust passage may be an air transportation air (compressor). ) To the suction port side, and the ventilation into the polishing tank can be a suction ventilation.

  The usage mode is the same as in the above embodiment.

  In the embodiment shown in FIGS. 6 to 7, in the embodiment shown in FIG. 5, a cooling means by a cooling water circulation circuit for cooling the body is further formed. In the present embodiment, the same or corresponding parts as those in the embodiment shown in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted in whole or in part.

  The structure of the cooling water circulation circuit is basically a structure in which the above air supply / exhaust means is combined except that a cooling water path (cooling liquid path) 82 is formed on the peripheral wall of the body. The cooling water channel 82 is formed as an independent channel on each side of the hexagon except for the lid forming portion.

  That is, the water supply side includes a main water supply channel in the revolution shaft, a sub water supply channel 88 in the rotation shaft 18 whose outlet side is connected (communication) to the inlet side of the fuselage cooling water channel 82, and a main water supply channel (not shown). Are provided with branch water supply pipes 86 that are arranged radially and connected to the sub water supply path 88.

  Further, the drain side is a main drainage channel in the revolution shaft, a sub drainage channel 98 in the rotation shaft 18 whose inlet side is connected to the outlet side of the fuselage cooling water channel 82, and a main drainage channel (not shown). And a collective drainage pipe 96 that is gathered radially toward the main drainage channel and connected to the main drainage channel.

  An outlet and an inlet of a cooling water circulation path 100 connected to an external cooler (heat exchanger) and provided with a circulation pump are respectively connected to the main water supply path and the main drainage path via a main rotary joint. In addition, although the flow direction of the cooling water in the polishing tank 20 is a counterflow opposite to the ventilation direction in the polishing tank 20, it may be a parallel flow.

  And in order to ensure the cooling effect of cooling water, the material of the body part and the side plate part of the polishing tank 20 is made of a member having high heat conductivity, and the liner layer 74 is also made of a member having high heat transfer coefficient, as described above. is doing.

  The usage mode of the above embodiment is also the same as that of each of the above embodiments.

  The polishing method of the present invention is suitable for heavy grinding polishing in which workpieces are made into innumerable cuts (chopped) prepared from a long circular cross-section material, and the cut end surfaces of each workpiece are rounded. The workpiece is not particularly limited as long as it is capable of being ground with a cross-section as well as the above-described long cross-section material. For example, the workpiece can be applied to edge polishing of a pressed product.

  Here, the cross-section circular long material includes a rod material (rod material), a wire material (coil material), and a pipe material (pipe material). Examples of products to which the polishing method of the present invention is applied include a micro shaft in a small motor.

  Next, a method of polishing a workpiece made of a coil wire chopped material using a polishing apparatus will be described (see FIGS. 1 and 5).

  First, a coil wire made of metal (usually steel) is cut (chopped) into a predetermined length with a cutting machine to prepare a work made of countless cut products.

  Next, the planetary rotating means is operated, that is, partially revolved, and the polishing tank 20 is positioned so that the opening / closing lid 21 is on the upper side, and the opening / closing lid 21 of the polishing tank 20 is opened by a cam operation. A work (object to be polished) and a fine abrasive powder are added together with a processing liquid (compound dispersion), and the open / close lid 21 is closed. Thereafter, the rotary drive source 12 is driven, and the valves of the external air supply pipe 62, the external exhaust pipe, and the water pipe 69 are opened.

  At this time, the volume of the mass composed of the work, the fine abrasive, and the processing liquid charged in the polishing tank 20 is preferably 45% or less. There is no possibility that the workpiece will jump out from the air supply port 57 or the exhaust port 67, or the fine powder abrasive that flows together with the machining fluid and the machining fluid during polishing will flow out. This is because, during operation, the input body having fluidity by centrifugal force is fluidly rotated while being pressed against the inner peripheral wall of the polishing tank by centrifugal force, and the central portion is always in a hollow state.

  Further, the rotation / revolution ratio is appropriately set between 1/1 and 2.5 / 1, and is appropriately set between an inclination angle of 0 to 15 ° with respect to the revolution axis of the rotation axis of the polishing tank. When polishing efficiency and polishing uniformity are required, rotation / revolution ratio: 1.5 / 1 to 2.5 / 1, preferably around 2, and an inclination angle of 5-15 °, preferably around 10 °. To do.

In addition, the basic rotational speed (revolution rotational speed) at this time varies depending on the size of the work (wire material shredded material), the work input amount, the polishing tank capacity, etc., for example, when the polishing tank capacity is 8 to 20 dm ³ , It sets suitably in the range of 120-200min- ¹ .

  Then, as the polishing tank rotates and revolves, the workpieces are repeatedly polished under pressure flow. Due to the pressure flow action, the edge portion of the workpiece is preferentially worn and rounded. The fine abrasive material serves as a medium in normal barrel polishing, but the size of the medium is reduced because it is selected and reused after polishing. However, since the fine abrasive is disposable every time, no sorting process is required. For this reason, there is no need to pay attention to replenishing a worn amount of media, equalizing the media diameter in the tank, and the like in the case of using media, and the polishing state in this embodiment is always stable.

  In this way, abrasion powder generated from the mass is generated in the processing liquid, and the processing liquid is in a slurry state having a high viscosity in combination with the dispersion of the fine powder abrasive. At this time, a large amount of frictional heat is generated, and the internal temperature tends to rise to near the boiling point (100 ° C.) of water that is a dispersion medium of the working fluid. When the wire is steel (iron-based alloy), hydrogen is generated and the internal pressure tends to increase.

  This hydrogen gas generation is presumed to be caused by the following chemical reaction.

Fe + 2H ₂ O → FeO + H ₂ ,
2Fe + 6H ₂ O → 2Fe (OH) ₃ + 3H ₂ O
At this time, since the ventilation (air supply / exhaust) is performed in the axial direction in the rotating / revolving polishing tank 20, the gas generated in the polishing tank 20 is also actively exhausted to the outside and the friction is generated. The generated heat is also taken away by water cooling, and the temperature rise of the workpiece is suppressed.

  At this time, water cooling is intermittently performed by spraying. At this time, the polishing tank body is provided with fins, and a liquid retention layer is formed by flocking, and the wall surface of the polishing tank body is cooled efficiently by vaporization heat cooling.

  Thus, it is not necessary to stop the operation of the polishing apparatus due to gas exhaust generated during edge polishing of the workpiece, and efficient and uniform edge polishing can be performed in one step.

  After the polishing is completed, after washing and rust prevention treatment is performed with the open / close lid 21 closed, the polishing tank 20 is positioned so that the open / close lid 21 is located on the lower side, and the mass (workpiece, processing liquid, Remove the fine powder abrasive) by falling under its own weight.

  Hereinafter, the procedure in which the polishing, cleaning, and rust prevention treatment shown in the above embodiments can be performed in series will be described in detail (mainly refer to FIG. 8).

  This cleaning / rust prevention treatment is heavy grinding and polishing such as R-attached to both edges of the workpiece as described above, and if the product is a precision part such as a microshaft, the main cleaning (for example, super This is a preliminary process (temporary cleaning / temporary rust prevention) for sonic cleaning and pure water cleaning). When the grinding is not heavy grinding and the main cleaning can be performed only with tap water, the main cleaning and the main antirust treatment can be performed by increasing the time of the cleaning and the antirust processing.

  After polishing, while rotating the polishing tank 20, one of the vents for venting in the axial direction of the polishing tank 20 is a liquid supply port (air supply port 57 in the illustrated example), and the other liquid discharge port (exhaust in the illustrated example). As a mouth 67), a cleaning liquid (tap water) is passed (water passing). Specifically, it is as follows.

  A water supply pipe is connected to the branch air supply pipe 56 via a switching valve (not shown: a normal electromagnetic switching valve) so that water can be supplied from the air supply port 57.

  The switching valve is operated to start water supply from the air supply port 57 into the polishing tank 20. The water level in the polishing tank 20 at the beginning of water supply after polishing is L1 shown in FIG. 8, but if the water level rises to L2, dirty water is discharged from the exhaust port 67 to the outside of the tank. Since the exhaust port 67 has a small diameter (20 mmφ), even if the exhaust port 67 is an open type that does not have an exhaust passage as shown in FIG. 2).

  At this time, since the polishing tank 20 substantially performs only rotation, the mass is rolled and washed inside. In this way, the polishing tank 20 continues to be in a water-permeable state, so that the cleaning proceeds in the initial, middle and final stages, and the cleaning ends. When cleaning is complete, close the selector valve and stop the tap water supply.

  Subsequently, with the tap water (cleaning liquid) remaining in the polishing tank 20, a rust preventive is further introduced through the air supply port 57. At this time, since the cleaning is completed, the tap water remaining in the polishing tank 20 is in a clean state. The rust preventive agent is introduced by providing a rust preventive agent supply path via an on-off valve (not shown) in the middle of the air supply pipe so that liquid can be supplied (supplied) by a pump or the like. And a rust prevention process can be given to a workpiece | work (to-be-polished object) by continuing autorotation continuously.

The rotation speed in each of the above washing and rust prevention treatments is appropriately set within a range of 10 to 30 min ⁻¹ . In addition, the cleaning (water flow) time and the antirust treatment time are appropriately set within the range of the former: 10 to 20 minutes and the latter: 1 to 3 minutes.

In the above, the cleaning and rust prevention treatment are performed intermittently by causing the polishing tank to undergo a partial revolution of less than one rotation, or intermittently or gradually changing the positional relationship of each polishing tank 20. Is desirable. Usually, since the tap water pressure is used as the power for supplying the cleaning water (tap water), a difference in the amount of water flow caused by the head (water head) occurs between the four polishing tanks 20. This is to compensate for this difference in water flow. For example, the rotation speed is 90 ° every minute or the rotation speed is 1 min ⁻¹ .

  Examples carried out to confirm the effects of the present invention will be described below.

<Test Example 1>
The polishing tank 20 is made of two types as shown in Table 1, polished under the following operating conditions, and sprayed with tap water from the outside of the polishing tank 20 every 10 minutes, the temperature in the polishing tank 20 and the amount of generated gas are determined. It was measured. The polishing tanks 20 were 8.5 dm ³ (polishing tank shape: hexagonal), and were attached at equal intervals so that the rotation shaft 18 was placed on the circumference of the rotating disk 16 at 590φ.

  The temperature in the tank was measured by inserting a thermometer directly after 1 h and 2 h, respectively. The amount of generated gas was measured by the water displacement method in the apparatus of FIG. 2 by introducing into the water only as exhaust without supplying air.

Polishing operation condition Rotating disk 16 Rotation speed 185min ^-1
Work load 10 kg / polishing tank 1 Water input 2 L / polishing tank 1 Abrasive (alumina) input 0.4 kg / polishing tank 1 compound (polishing aid) 5 g / polishing tank 1 The above test results are shown From Table 1, the following can be understood.

  In Examples 1 and 2 that were spray-cooled, the increase in internal temperature was small and the amount of gas generated was also small compared to Comparative Examples 1 and 2 that were not spray-cooled. In particular, the polishing tank 20 is spray-cooled with the lining layer and the main body layer made of wear-resistant iron and iron with high thermal conductivity, respectively, and the main body coating layer made of toweling with high liquid retention (water retention). No. 1 has a good cooling efficiency and increased internal temperature, compared to Example 2 in which the outer surface of a general-purpose polishing tank with a lining layer: wear-resistant rubber and a body layer: iron was used for towel cooling. The amount of gas generated is also extremely small.

＜試験例２＞
研磨槽２０の構成が実施例１のものについて、研磨槽２０の姿勢（水平又は傾斜）及び自公転比（１／１又は２／１）を変えて、運転条件を試験例１と同様とし、水道水による噴霧冷却を１０分毎に行った場合の研磨効率の判定を行った。

<Test Example 2>
For the configuration of the polishing tank 20 of Example 1, the operating condition is the same as in Test Example 1 by changing the posture (horizontal or tilt) and the rotation and revolution ratio (1/1 or 2/1) of the polishing tank 20, The polishing efficiency was determined when spray cooling with tap water was performed every 10 minutes.

  Judgment method is that after measuring 2h by mixing 10 markers of Φ7mm × L10mm whose size is clearly different from the workpiece in innumerable workpieces (10kg) whose size per piece is Φ2mm × L20mm, The weight of 10 markers was measured to calculate the polishing amount and its variation. The inclination angle of the polishing tank was 9 °.

  The results are shown in Table 2. When the polishing tank 20 is tilted, the variation in the polishing amount is small compared to the horizontal state. This is presumed to be because the agitation (disturbance) movement of the workpiece is smoothly performed in the polishing tank 20. In addition, the higher the rotation rate, the larger the polishing amount and the better the polishing efficiency. This is presumed to be because the reversal frequency of the work in the polishing tank 20 is high.

＜試験例３＞
表３に示す各種バレル装置を使用して、ワークを、メディア（実施例はメディアの代わりに微粉研磨材）、コンパウンド及び水とともに、それぞれ記載する量を投入して、無数の線材細断物をワークとしてエッジ研磨を行った。

<Test Example 3>
Using the various barrel devices shown in Table 3, the workpiece is put together with the media (in the example, fine powder abrasive instead of the media), compound and water, and the amounts described respectively are added, and innumerable wire strips are cut. Edge polishing was performed as a workpiece.

  The size of the wire shredded material used as the workpiece is 2.5φ × 16L, and the polishing tank 20 forms an electrostatic flocking layer of nylon short fibers on a conventional body (SS400: 10 mmt). The tilt angle was 9 °, the rotation / revolution ratio was 1/1 (the same applies to Comparative Example 3), and water spraying was performed at 10 min intervals (spraying time: 15 s).

そして、ワークの両端面のエッジ部に所定の丸みを付けるまでの時間を研磨完了とし、その時間（研磨時間）及びそのときのワーク研磨量・メディア（又は微粉研磨材）損耗量をそれぞれ測定した。表４に示す結果から下記のことが分かる。

Then, the time until the predetermined roundness is applied to the edge portions of the both end faces of the workpiece is defined as polishing completion, and the time (polishing time) and the amount of workpiece polishing / media (or fine powder abrasive) wear at that time are measured. . From the results shown in Table 4, the following can be understood.

  In Example 2, the polishing time is as short as 2 h, and the input amount (processing amount) is large with respect to the capacity of the polishing tank 20 of the workpiece (aggregate of wire rods). This is because no media is used as compared with Comparative Examples 2-1, 2 and 3. The amount of input can be significantly increased. Therefore, it means that the productivity of workpiece edge polishing (heavy grinding polishing) is remarkably improved.

  Moreover, although the fine abrasive (alumina fine powder) is disposable, the amount used per time is less than the amount of wear of the media. For this reason, the running cost per unit amount of the work becomes extremely low considering that the price of the fine powder abrasive is also lower than that of the normal medium.

  In each comparative example, a process of separating and separating the media from the work (product) is necessary after the polishing is completed. However, in the present embodiment, the process is unnecessary because of the co-grinding. In normal polishing using media, in order to facilitate sorting, it is necessary to use media having a size that can be identified (sorted) compared to the workpiece.

なお、実施例２に示すワークのエッジ研磨（共摺り研磨）を、従来の、水（冷却液）を吹き付けずに、且つ、研磨槽２０内の換気を行わずに、従来法で湿式遠心バレル研磨を行うと、研磨槽２０内の圧力上昇、水素ガス等の発生があり、連続運転が可能な時間は、３０min程度であることを本発明者らは確認している。

In addition, the edge grinding | polishing (co-grinding grinding | polishing) of the workpiece | work shown in Example 2 does not spray the conventional water (cooling liquid), and does not ventilate in the grinding | polishing tank 20, but is a conventional wet centrifugal barrel. When polishing is performed, the inventors have confirmed that the pressure in the polishing tank 20 is increased and hydrogen gas is generated, and the continuous operation time is about 30 minutes.

<Test Example 4>
In order to see the cooling effect by spraying the coolant (water), the same configuration as in the above example (reference example 1), with the rubber lining (7 mmt) in the example (reference example 2), and without toweling in the example (reference example) 3) With respect to each configuration, the workpiece is polished by wet centrifugal barrel polishing in a sealed manner under the same conditions as in Example 1 except that ventilation is not performed (Reference Example 3 is not cooled). The temperature inside 20 was measured every 1 h, and the internal pressure and the amount of gas generated were degassed every 0.5 h.

  In Reference Examples 2 and 3, the pressure increase rate in the polishing tank 20 is fast, and the operation cannot be continued in a sealed state. Therefore, in Example 2, after 0.5 h, in Example 3, every 10 minutes from the beginning. The gas was vented and the amount of generated gas and pressure were measured each time (Reference Example 2 and Reference Example 3 are cumulative values for both generated gas amount and pressure).

  The following can be understood from Table 5 showing the test results.

  In Reference Example 1, when the liquid retaining layer (towel material) is provided, the heat generated by the friction between the workpieces is taken away from the surface of the polishing tank by the heat of vaporization, so that the temperature rise can be suppressed to some extent. Even so, the increase in internal pressure and the amount of generated gas can be suppressed to some extent. However, since ventilation is not performed, the internal pressure of the polishing tank 20 after 2 hours is 0.087 MPa, and the amount of gas generated is also 12.5 L in total. For this reason, it turns out that ventilation is inevitable.

  In Reference Example 2, cooling is performed by water spraying, but since the lining layer is a rubber material having low heat conductivity, the cooling effect is inferior and the effect of suppressing the increase in internal pressure and gas generation is small.

  In Reference Example 3, since cooling by water spraying is not performed, it can be seen that there is no effect of suppressing internal pressure increase and gas generation, the internal pressure increase rate is extremely fast, and the amount of gas generation is extremely large.

＜試験例５＞
次に、研磨終了後の後処理工程である洗浄・防錆処理における洗浄・防錆効果に関し、実用機を用いて確認した。

<Test Example 5>
Next, the cleaning / rust prevention effect in the cleaning / rust prevention treatment, which is a post-treatment process after the polishing, was confirmed using a practical machine.

Model used (practical machine): countless steel wire rods (φ20mm × L20mm) in each polishing tank 20 of “centrifugal barrel polishing machine SKC type” (manufactured by Shinto Blator Co., Ltd.) equipped with 4 polishing tanks 20 Along with 20 kg of the workpiece, 1 kg of abrasive (alumina powder), 10 g of polishing aid and 4 L of tap water were added. The polishing tank 20 having a capacity of 20 dm ^{3 with} the specifications shown in FIG. 5 was used.

And polishing 3h was performed on the conditions of autorotation rotation speed: 140min < ^-1 >, autorotation ratio 1: 1. During this polishing, spray cooling was performed in the same manner as in Test Example 1, and after the polishing was completed, washing and rust prevention treatment were continuously performed.

As an evaluation of the degree of cleaning, the amount of suspended matter in the discharged water was measured with respect to the total amount of water supplied in the polishing tank 20, and the results are shown in Table 6. The amount of water supply that gave the best cleaning effect was 120 L / tank. At this time, the rotation speed was set to 15 min ⁻¹ and the intermittent revolution was set to 90 ° min ⁻¹ .

In addition, the rust prevention treatment was performed for 2 minutes by introducing a 1% diluted solution of “Compound SLM” (manufactured by Shinto Blator Co., Ltd.) into 5 L / tank. At this time, rotation rpm: 15min and ^-1, the revolution was 90 ° · 0.5 min ^-1.

1 is an overall schematic side view of a polishing apparatus of the present invention. It is a general | schematic fragmentary sectional view which shows one Embodiment of the grinding | polishing apparatus of this invention. FIG. 3 is an end view taken along line 3-3 in FIG. 2. FIG. 3 is an enlarged sectional view of four parts in FIG. 2. It is principal part sectional drawing which shows other embodiment in the grinding | polishing apparatus of this invention. It is principal part sectional drawing which shows other embodiment similarly. FIG. 7 is an end view taken along line 67 in FIG. 6. It is the vertical model cross section for description about the washing | cleaning after this grinding | polishing process in the grinding | polishing method of this invention, and the model cross section.

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 Revolving shaft 16 Rotating disk 18 Rotating shaft 20 Polishing tank 32 Planetary rotating device 34 Sun gear 36 Planetary gear 56 Branch air supply piping 57 Air supply port 58 Sub air supply passage 67 Exhaust port 70 Coolant spray means

Claims (9)

In the centrifugal barrel polishing apparatus in which the ventilation means is formed in the rotation axis direction of the polishing tank, the polishing tank includes a plurality of polishing tanks that rotate and revolve, and the cabinet body that houses the polishing tanks includes the ventilation means .
The body and side plates of the polishing tank are made of a member having high thermal conductivity, and the outer peripheral surface of the body is covered with a heat exchange medium made of a member having high thermal conductivity and / or liquid retention. A centrifugal barrel polishing apparatus comprising a cooling means for allowing a cooling liquid to be sprayed onto a heat exchange medium of the polishing tank that rotates and revolves therein . A cooling fluid passage is formed in the body of the polishing tank, a liquid supply passage is connected to one of the cooling fluid passages, and a drainage passage is connected to the other, and the liquid supply passage and the drainage passage are connected to a heat exchanger. The centrifugal barrel polishing apparatus according to claim 1 , wherein the centrifugal barrel polishing apparatus is connected to a circulation path provided. The inner surface of the body portion and the side plate portion of the polishing tank, of the exchange freely abrasion resistance provided liner claims, characterized in that the liner of at least the body portion is formed with high member thermal conductivity Item 3. The centrifugal barrel polishing apparatus according to Item 1 or 2 . 4. The centrifugal barrel polishing apparatus according to claim 1, wherein a mist collector is connected to the ventilation means . Ventilation means is formed in the direction of the rotation axis of the polishing tank, and a plurality of polishing tanks that rotate and revolve are provided. A cabinet body that houses the plurality of polishing tanks is provided with ventilation means, and a body portion of the polishing tank; The side plate portion is formed of a member having a high thermal conductivity, and the outer peripheral surface of the body portion is covered with a heat exchange medium made of a member having a high thermal conductivity and / or a liquid retention rate, and rotates and revolves during polishing. Using a centrifugal barrel polishing apparatus provided with cooling means for spraying a cooling liquid onto the heat exchange medium of the polishing tank, the edge R of the metal workpiece (hereinafter referred to as “workpiece”) is used. A barrel polishing method for rounding,
A centrifugal barrel polishing method characterized by polishing the inside of the polishing tank while ventilating the inside of the cabinet body while ventilating in the rotation axis direction of the polishing tank and cooling the body part and the side plate part . In the centrifugal barrel polishing method, while each polishing tank is rotated after polishing, one air supply port for venting in the rotation axis direction of the polishing tank is used as a liquid supply port, and the other exhaust port is used as a liquid discharge port. 6. The centrifugal barrel polishing method according to claim 5 , wherein the inside of the polishing tank and the workpiece are cleaned by passing a cleaning solution as an outlet. Each of the polishing tanks is subjected to cleaning treatment and / or prevention while changing the positional relationship between the polishing tanks intermittently by partially revolving less than one revolution or continuously by revolving at low speed without generating centrifugal force. 7. The centrifugal barrel polishing method according to claim 6, wherein rust treatment is performed. After the cleaning process is finished, with the cleaning liquid remaining in the polishing tank, and after adding a rust preventive agent from the liquid supply port, the polishing tank is rotated to perform a rust preventive process on the workpiece. The centrifugal barrel polishing method according to claim 6 or 7, characterized in that: The centrifugal barrel polishing method according to claim 6, 7 or 8, wherein the rotation speed of the polishing tank in the cleaning treatment or rust prevention treatment is set in a range of 10 to 30 min ^-1 .

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