Grinding fluid spraying device

Abstract

The present invention provides a grinding fluid spraying device that can supply a sufficient amount of grinding fluid to the vicinity of the corners in the width direction of the grinding surface of the grinding wheel. [Solution] The grinding fluid spraying device comprises a device body and three nozzles. The device body comprises a left-swirling flow generating unit that generates a left-swirling flow, a right-swirling flow generating unit that generates a right-swirling flow, and a non-swirling flow generating unit that generates a non-swirling flow. The non-swirling flow generating unit generates a non-swirling flow by colliding and mixing a part of the left-swirling flow with a part of the right-swirling flow. The first nozzle is configured to be able to take a position in which it can spray a left-swirling flow FLL onto the left corner 21d and its surroundings at the contact start point P. The second nozzle is configured to be able to take a position in which it can spray a non-swirling flow onto the grinding surface 21a and its surroundings at the contact start point P. The third nozzle is configured to be able to take a position in which it can spray a right-swirling flow FLR onto the right corner 21e and its surroundings at the contact start point P.

Description

Technical Field

[0001] The present invention relates to a grinding fluid injection device that injects grinding fluid onto a grinding wheel of a grinding apparatus.

Background Art

[0002] A grinding fluid injection device for injecting grinding fluid is attached to the grinding wheel of a grinding apparatus. By injecting grinding fluid from the grinding fluid injection device onto the grinding wheel, cooling of the grinding wheel and removal of chips adhering to the grinding surface (outer peripheral surface) of the grinding wheel can be achieved. Specifically, as shown in FIG. 9(a), the grinding fluid injection device injects the grinding fluid pressurized by a pump or the like from a nozzle 911 disposed near the grinding wheel 921 (jet flow JS). The injection of the grinding fluid onto the grinding wheel 921 rotating as indicated by the arrow E1 is performed at the contact start point of the grinding area with the workpiece 950 on the grinding surface (outer peripheral surface) 921a of the grinding wheel 921 or at a location on the upstream side in the rotation direction of the point. As such a grinding fluid injection device, the applicant of the present application has previously proposed (Patent Document 1).

[0003] The grinding fluid injection device disclosed in Patent Document 1 is configured to divide the grinding fluid supplied from a supply source, generate a left-handed swirling flow and a right-handed swirling flow, and then collide and mix the two swirling flows to inject them as a non-swirling jet flow onto the grinding surface (outer peripheral surface) of the grinding wheel.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the grinding fluid injection device disclosed in the above Patent Document 1, by injecting a non-swirling jet flow onto the grinding surface of the grinding wheel, the grinding fluid can be uniformly supplied in the width direction of the grinding surface.

[0006] However, it is believed that there is room for improvement in the prior art, including the technology disclosed in Patent Document 1 mentioned above. This will be explained in detail using Figure 9(b).

[0007] As shown in Figure 9(b), when the grinding wheel 921 is viewed from the front, from the upstream side in the rotational direction of the grinding wheel 921, the jet JS from the nozzle 911 is sprayed onto the grinding surface 921a of the grinding wheel 921. In this case, there is a concern that a sufficient amount of grinding fluid may not be present near the corners 921d and 921e located at the ends of the grinding wheel 921 in the width direction, and near the corners 921d and 921e on the grinding surface 921a. That is, the pressure of the grinding fluid sprayed onto the grinding surface 921a gradually decreases from the center of the grinding wheel 921 in the width direction towards the corners 921d and 921e, and the grinding fluid is released outward in the width direction from the corners 921d and 921e, which can result in a lack of sufficient grinding fluid at the corners 921d and 921e, etc. If a sufficient amount of grinding fluid is not present in the corners 921d, 921e, etc., it is possible that the temperature in that area will rise, and problems such as the inability to properly remove chips may occur.

[0008] The present invention aims to solve the above-mentioned problems and provides a grinding fluid spraying device that can supply a sufficient amount of grinding fluid to the corners in the width direction of the grinding surface of the grinding wheel. [Means for solving the problem]

[0009] A grinding fluid spraying device according to one aspect of the present invention is a grinding fluid spraying device for spraying grinding fluid onto a disc-shaped grinding wheel in a grinding device, comprising: a left-turning flow generation unit that receives the grinding fluid from a supply source and generates a left-turning flow of the grinding fluid as it moves while turning left; a right-turning flow generation unit that receives the grinding fluid from the supply source and generates a right-turning flow of the grinding fluid as it moves while turning right; a non-turning flow generation unit that generates a non-turning flow of the grinding fluid as it moves without turning; a first nozzle that sprays the remainder of the left-turning flow; a second nozzle that sprays the non-turning flow; and a third nozzle that sprays the remainder of the right-turning flow, wherein the device contacts the upstream end of the grinding wheel in the direction of rotation within the grinding area of ​​the grinding wheel with respect to the workpiece during grinding. When the contact initiation point is viewed from the front from the opposite side of the grinding region in a direction perpendicular to the rotation axis of the grinding wheel, the first nozzle is configured to be able to spray the remainder of the left-swirling flow onto the left corner and its surrounding area, which is the boundary between the left side surface of the grinding wheel and the grinding surface of the grinding wheel at the contact initiation point; the second nozzle is configured to be able to spray the non-swirling flow onto the grinding surface and its surrounding area at the contact initiation point; and the third nozzle is configured to be able to spray the remainder of the right-swirling flow onto the right corner and its surrounding area, which is the boundary between the right side surface of the grinding wheel and the grinding surface at the contact initiation point.

[0010] In the grinding fluid spraying device according to the above embodiment, a left-swirling flow is sprayed from the first nozzle to the left corner and surrounding area of ​​the grinding wheel, and a right-swirling flow is sprayed from the third nozzle to the right corner and surrounding area of ​​the grinding wheel. As a result, sufficient grinding fluid can be supplied to both corners of the grinding surface at the point of contact. Specifically, in the above grinding fluid spraying device, by spraying a left-swirling flow to the left corner, a portion of the ejected flow is made to wrap around from the left corner to the grinding surface, and by spraying a right-swirling flow to the right corner, a portion of the ejected flow is made to wrap around from the right corner to the grinding surface. Therefore, sufficient grinding fluid can be supplied to both corners of the grinding surface by these wrap-arounds, and the portion of the ejected flow that wraps around from both corners also prevents the grinding fluid sprayed from the second nozzle onto the grinding surface from escaping outward in the width direction of the grinding wheel from both corners.

[0011] Furthermore, in the grinding fluid spraying device according to the above embodiment, since the second nozzle is configured to spray a non-swirling flow onto the grinding surface, it is possible to suppress the grinding fluid sprayed onto the grinding surface from becoming biased to one side in the width direction of the grinding surface. That is, when spraying a left-swirling flow or a right-swirling flow onto the grinding surface, there is a concern that the grinding fluid on the grinding surface will become biased in the swirling direction, but since a non-swirling flow is sprayed onto the grinding surface, it is possible to suppress the bias of the grinding fluid on the grinding surface.

[0012] In the grinding fluid spraying device according to the above embodiment, the non-swirling flow generation unit may be configured to generate the non-swirling flow by colliding and mixing a part of the left-swirling flow with a part of the right-swirling flow.

[0013] In the grinding fluid injection device according to the above embodiment, the non-swirling flow generation unit has a configuration that generates a non-swirling flow of grinding fluid by colliding and mixing a portion of the left-swirling flow and a portion of the right-swirling flow. Therefore, the overall configuration of the device can be simplified compared to the case in which a non-swirling flow is generated without using a portion of the left-swirling flow generated by the left-swirling flow generation unit and a portion of the right-swirling flow generated by the right-swirling flow generation unit. Thus, the above grinding fluid injection device can suppress an increase in the size of the device and an increase in the cost of the device.

[0014] In the grinding fluid spraying device according to the above embodiment, the left-swirling flow generation unit, the right-swirling flow generation unit, and the non-swirling flow generation unit are formed within a casing which is connected a receiving-side casing having a receiving section for receiving the grinding fluid from the supply source, a discharge-side casing to which the first nozzle, the second nozzle, and the third nozzle are connected, and an intermediate casing connecting the receiving-side casing and the discharge-side casing, and the discharge-side casing is formed within the left-swirling flow generation unit. A configuration may be adopted in which the non-swirling flow generation unit is composed of a non-swirling flow connection path formed in the discharge-side casing, which guides a portion of the left-swirling flow to the connection point of the first nozzle, a right-swirling flow connection path which guides a portion of the right-swirling flow generated in the right-swirling flow generation unit to the connection point of the third nozzle, and a non-swirling flow connection path which connects the left-swirling flow connection path and the right-swirling flow connection path and guides the non-swirling flow generated by collision mixing at the connection point to the connection point of the second nozzle.

[0015] In the grinding fluid injection device according to the above embodiment, a non-swirling flow connection passage is formed in the discharge-side casing, and a non-swirling flow generation unit is configured by this non-swirling flow connection passage, so that a non-swirling flow can be generated with a simple configuration. Therefore, it is possible to suppress the increase in the size of the device and the increase in device costs.

[0016] In the grinding fluid spraying device according to the above embodiment, the non-swirling flow connection passage may have a connecting passage that connects the left swirling flow connection passage and the right swirling flow connection passage, and a connecting passage that is connected to the connecting passage and extends to the connection portion of the second nozzle in a direction intersecting the direction in which the connecting passage extends, and the discharge-side casing may further have a reservoir that is connected to the connecting passage and is provided on the side opposite to the connecting passage in the direction in which the connecting passage extends, for temporarily accumulating the non-swirling flow.

[0017] In the grinding fluid injection device according to the above embodiment, a reservoir is provided in the discharge-side casing, so that a portion of the left-swirling flow and a portion of the right-swirling flow collide and are thoroughly mixed in the reservoir. Therefore, the above grinding fluid injection device can reliably generate a non-swirling flow within the discharge-side casing.

[0018] Furthermore, in the above-described grinding fluid injection device, the direction of travel of the non-swirling flow formed by collision mixing in the connecting passage can be changed by the accumulation section to the direction in which the connecting passage extends. Therefore, in the above-described grinding fluid injection device, the non-swirling flow generated in the connecting passage can be guided to the connection section of the second nozzle with high efficiency.

[0019] In the grinding fluid spraying device according to the above embodiment, the intermediate casings may be configured such that they are separated from each other by partition walls, and each has a first space and a second space that extend from the coupling side of the receiving casing to the coupling side of the discharge casing such that the cross-sectional size gradually decreases, the left-swirling flow generating unit is housed in the first space and has a first shaft body having a helical groove portion formed on its outer circumference to swirl leftward from the coupling side of the receiving casing to the coupling side of the discharge casing, and the right-swirling flow generating unit is housed in the second space and has a second shaft body having a helical groove portion formed on its outer circumference to swirl rightward from the coupling side of the receiving casing to the coupling side of the discharge casing.

[0020] In the grinding fluid injection device according to the above embodiment, a left-swirling flow generation unit is formed by a first shaft body housed in a first space and having a helical groove portion arranged to swirl left, and a right-swirling flow generation unit is formed by a second shaft body housed in a second space and having a helical groove portion arranged to swirl right. Therefore, the grinding fluid introduced into the first space flows along the helical groove portion of the first shaft body, resulting in a left-swirling flow, and the grinding fluid introduced into the second space flows along the helical groove portion of the second shaft body, resulting in a right-swirling flow. In this way, the above grinding fluid injection device can generate both left-swirling and right-swirling flows with a simple configuration.

[0021] In the grinding fluid injection device according to the above aspect, each of the first shaft body and the second shaft body is provided with a plurality of convex portions that are formed protruding between the adjacent spiral groove portions in the circumferential direction and have a rhombus shape in a plan view from the radially outer side, and the plurality of convex portions are arranged with a gap between adjacent ones in the direction from the coupling side of the receiving side casing to the coupling side of the discharge side casing. A configuration as described above may be adopted.

[0022] In the grinding fluid injection device according to the above aspect, as described above, since the first space is formed so as to extend such that the cross-sectional size gradually decreases from the coupling side of the receiving side casing to the coupling side of the discharge side casing, as is clear from Bernoulli's theorem, the static pressure of the grinding fluid introduced into the first space decreases as it advances toward the discharge side. In this case, by configuring the first space such that the static pressure of the grinding fluid reaches the saturated vapor pressure, a cavitation phenomenon can be caused in the grinding fluid.

[0023] Further, in the above grinding fluid injection device, since the first shaft body has the plurality of convex portions as described above, a mesh-like flow path is formed on the circumferential surface of the first shaft body by the plurality of convex portions. Therefore, the grinding fluid introduced into the first space can repeatedly divide and merge through the mesh-like flow path of the first shaft body, generating a large number of fine vortices due to the flip-flop phenomenon and generating fine bubbles.

[0024] Regarding the second space, since it is also formed so as to extend such that the cross-sectional size gradually decreases from the coupling side of the receiving side casing to the coupling side of the discharge side casing, the static pressure of the grinding fluid introduced into the second space also decreases as it advances toward the discharge side, and it is possible to cause a cavitation phenomenon in the grinding fluid.

[0025] Further, regarding the second shaft body, similar to the first shaft body, since it has a plurality of convex portions as described above, the grinding fluid introduced into the second space can repeatedly divide and merge by advancing through the mesh-like flow path formed on the circumferential surface of the second shaft body, generating a large number of fine vortices due to the flip-flop phenomenon and generating fine bubbles.

[0026] As described above, in the grinding fluid injection device, since each of the left-handed swirl flow, right-handed swirl flow, and non-swirl flow contains fine bubbles, the injected grinding fluid adheres to the grinding surface of the grindstone (Coandă effect), and when it collides with the grinding surface, the bubbles are likely to bounce off (cavitation phenomenon), enabling the cooling and cleaning of the grindstone.

[0027] In the grinding fluid injection device according to the above aspect, a flow rate adjustment valve may be further provided between the non-swirl flow generation part and the injection port of the second nozzle in the flow path of the non-swirl flow, for adjusting the injection flow rate of the non-swirl flow.

[0028] In the grinding fluid injection device according to the above aspect, since a flow rate adjustment valve is provided in the flow path of the non-swirl flow, the flow rate (injection amount) of the non-swirl flow injected can be adjusted according to the grit size of the grindstone. That is, when using a grindstone with a large grit size, even if the same flow rate of grinding fluid is supplied to the grinding surface, a hydroplaning phenomenon is more likely to occur compared to when using a grindstone with a small grit size. In order to prevent the occurrence of the hydroplaning phenomenon, when using a grindstone with a large grit size, it is preferable to reduce the amount of grinding fluid injected onto the grinding surface compared to when using a grindstone with a small grit size. Therefore, in the above grinding fluid injection device, by providing a flow rate adjustment valve capable of adjusting the amount of grinding fluid injected onto the grinding surface, the flow rate can be adjusted according to the grit size of the grindstone, and the occurrence of the hydroplaning phenomenon can be suppressed.

Effect of the Invention

[0029] The grinding fluid injection device according to each of the above aspects can supply a sufficient amount of grinding fluid to the vicinity of the corner in the width direction with respect to the grinding surface of the grindstone.

Brief Description of the Drawings

[0030] [Figure 1] It is a schematic diagram showing the schematic configuration of the grinding fluid injection device according to the embodiment. [Figure 2] It is a plan view showing the configuration of the device main body in the grinding fluid injection device. [Figure 3]This is a cross-sectional view showing a portion of the internal components of the main body of the device. [Figure 4] (a) is a side view showing the configuration of the first shaft body, and (b) is an end view of the large diameter section as seen from the direction indicated by arrow B in (a). [Figure 5] This is a schematic diagram showing the swirling direction of the grinding fluid introduced into the discharge casing. [Figure 6] Figure 5 is a cross-sectional view showing the configuration of the section along the line VI-VI. [Figure 7] This is a cross-sectional view showing the configuration of the section along line VII-VII in Figure 6. [Figure 8] This is a schematic diagram showing the spray pattern of grinding fluid onto the grinding wheel. [Figure 9] (a) is a schematic diagram showing the configuration of a conventional injection device, and (b) is a schematic diagram showing the injection pattern of grinding fluid onto a grinding wheel when using the conventional injection device. [Modes for carrying out the invention]

[0031] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are illustrative examples of the present invention, and the present invention is not limited to these embodiments except for its essential configuration.

[0032] [Embodiment] 1. Schematic configuration of grinding fluid spraying device 1 The schematic configuration of the grinding fluid spraying device 1 according to this embodiment will be explained with reference to Figure 1.

[0033] As shown in Figure 1, the grinding fluid spraying device 1 is a device that sprays grinding fluid onto the grinding wheel 21 of the grinding device 20, and is attached to the grinding device 20. The grinding device 20 is equipped with a table 22 on which a workpiece 500 can be placed, and with the workpiece 500 placed on the table 22, the grinding wheel 21 rotates around the rotation axis Ax21 (arrow A1), and the table 22 moves left, right, forward, and backward (arrow A2).

[0034] The grinding fluid spraying device 1 according to this embodiment comprises a device body 10 and three nozzles 11 to 13. Each of the three nozzles 11 to 13 comprises a nozzle body 11a, 12a, and 13a that constitutes an opening for spraying grinding fluid toward the grinding wheel 21, and flexible tubes 11b, 12b, and 13b that are connected to the nozzle bodies 11a, 12a, and 13a and have flexibility.

[0035] The main body of the device 10 is connected to the flexible tubes 11b, 12b, and 13b of each nozzle 11 to 13, as well as to the piping 4. The other end of the piping 4 is connected to the grinding fluid storage tank 2 via the pump 3.

[0036] The grinding fluid storage tank 2 is a tank for storing grinding fluid and is the source of the grinding fluid supply. The pump 3 sends grinding fluid from the grinding fluid storage tank 2 to the main body 10 of the grinding fluid injection device 1. A shut-off valve may be provided in the piping 4. If a shut-off valve is provided in the piping 4 in this way, the shut-off valve can be closed when the grinding device 20 is stopped, preventing the grinding fluid from being sent to the main body 10 of the device.

[0037] 2. Configuration of the main body 10 and its surroundings in the grinding fluid spraying device 1 The configuration of the main body 10 and its surroundings in the grinding fluid spraying device 1 will be explained with reference to Figures 2 and 3.

[0038] As shown in Figure 2, the main body of the apparatus 10 comprises a receiving-side casing 101 having a connection part 101a to which the piping 4 is connected, a discharge-side casing 102 having connection parts 102a to 102c to which the nozzles 11 to 13 are connected, and an intermediate casing 100 that liquid-tightly connects the receiving-side casing 101 and the discharge-side casing 102. The connection part 101a in the receiving-side casing 101 is a receiving part that receives grinding fluid from the supply source (grinding fluid storage tank 2).

[0039] Furthermore, when the three nozzles 11 to 13 are arranged in the Y-direction as the first nozzle 11, the second nozzle 12, and the third nozzle 13, the first nozzle 11 and the third nozzle 13 are connected to connection portions 102a and 102c formed to be recessed inward from the end face 1102d of the discharge-side casing 102, and the second nozzle 12 is connected to connection portion 102b formed to be recessed inward from the upper surface 102e of the discharge-side casing 102. However, in the discharge-side casing 102, the connection portion 102b to which the second nozzle 12 is connected may also be formed to be recessed inward from the end face 102d, and the connection portions 102a and 102c to which the first nozzle 11 and the third nozzle 13 are connected may also be formed to be recessed inward from the upper surface 102e.

[0040] As shown in Figure 3, the receiving casing 101 has an inwardly formed space 101b. Space 101b is the space through which grinding fluid from the piping 4 is introduced via the connection part 101a. The intermediate casing 100 has a first space 100a and a second space 100b, which are partitioned from each other by a partition wall 100c. Each of the first space 100a and the second space 100b is a cylindrical space extending in the X direction. The first space 100a and the second space 100b are arranged side by side in the Y direction.

[0041] Here, the first space 100a and the second space 100b are configured such that the cross-sectional size gradually decreases as you move from the receiving casing 101 side to the discharging casing 102 side. Specifically, in the first space 100a, the inner diameter on the receiving casing 101 side is D1, while the inner diameter gradually decreases as you move toward the discharging casing 102 side in the X direction, so that the inner diameter on the discharging casing 102 side is D2, which is smaller than the inner diameter D1. Similarly, in the second space 100b, the inner diameter is D3 on the receiving casing 101 side, while the inner diameter gradually decreases as you move toward the discharging casing 102 side in the X direction, so that the inner diameter on the discharging casing 102 side is D4, which is smaller than the inner diameter D3.

[0042] The main body 10 of the grinding fluid spraying device 1 according to this embodiment includes a first shaft body 15 housed in the region extending from space 101b of the receiving casing 101 to the first space 100a, and a second shaft body 16 housed in the region extending from space 101b of the receiving casing 101 to the second space 100b. The first shaft body 15 and the second shaft body 16 have their respective axes aligned along the X direction, and their axes are aligned in the Y direction. The detailed configuration of the first shaft body 15 and the second shaft body 16 will be described later.

[0043] The discharge-side casing 102 has a first inlet 102f and a second inlet 102g formed on its interior. The first inlet 102f is a funnel-shaped space whose inner diameter gradually decreases as it moves away from the side to which the intermediate casing 100 is joined in the X direction, and is continuous with the first space 100a of the intermediate casing 100. The second inlet 102g is a funnel-shaped space whose inner diameter gradually decreases as it moves away from the side to which the intermediate casing 100 is joined in the X direction, and is continuous with the second space 100b of the intermediate casing 100.

[0044] Although not shown in Figure 3, sealing materials such as O-rings are interposed between the joint surfaces of the receiving casing 101 and the intermediate casing 100, and between the joint surfaces of the intermediate casing 100 and the discharge casing 102.

[0045] In the apparatus body 10 having the above configuration, the grinding fluid introduced into the space 101b of the receiving casing 101 is divided into the first space 100a and the second space 100b of the intermediate casing 100 and sent to the first inlet 102f and the second inlet 102g of the discharge casing 102. As will be described in detail later, the grinding fluid moving through the first space 100a toward the first inlet 102f is given a flow direction such that it turns left along the circumferential surface of the first shaft body 15, and the grinding fluid moving through the second space 100b toward the second inlet 102g is given a flow direction such that it turns right along the circumferential surface of the second shaft body 16. In other words, in the grinding fluid spraying device 1 according to this embodiment, a left-handed swirling flow generation unit 17 is configured by a first space 100a and a first shaft body 15 housed in the first space 100a to generate a left-handed swirling flow of grinding fluid, and a right-handed swirling flow generation unit 18 is configured by a second space 100b and a second shaft body 16 housed in the second space 100b to generate a right-handed swirling flow of grinding fluid.

[0046] 3. Configuration of the first shaft body 15 and the second shaft body 16 The configurations of the first shaft 15 and the second shaft 16 will be explained using Figure 4. Note that Figure 4 only shows the first shaft 15, and the second shaft 16 is not shown. The following will explain the first shaft 15, and for the second shaft 16, only the differences from the first shaft 15 will be explained.

[0047] As shown in Figure 4(a), the first shaft body 15 is constructed with a cylindrical body extending along the X direction as its base, and has a base shaft portion 15a and a swivel-providing portion 15b that are continuous with each other in the X direction. In this embodiment, the base shaft portion 15a is housed in the space 101b of the receiving casing 101, and the swivel-providing portion 15b is housed in the first space 100a of the intermediate casing 100 (see Figure 3). However, it is also possible to adopt a configuration in which a part of the base shaft portion 15a enters the first space 100a, or a configuration in which a part of the swivel-providing portion 15b enters the space 101b in the receiving casing 101.

[0048] The end face 15f of the base shaft portion 15a abuts without gap against the inner wall surface in the X direction facing the space 101b when the base shaft portion 15a of the first shaft body 15 is housed in the space 101b of the receiving side casing 101.

[0049] The swivel-providing section 15b has multiple large-diameter sections 15c that are expanded radially outward from the cylindrical body. As shown in Figure 4(b), the large-diameter sections 15c are arranged alternately with convex sections 15d that protrude radially outward in the circumferential direction and helical groove sections 15e formed between adjacent convex sections 15d in the circumferential direction. In the front view shown in Figure 4(b), the large-diameter sections 15c as a whole have a gear shape.

[0050] As shown in Figure 4(a), when viewed from the radially outer side, each protrusion 15d has a rhombic shape. The helical groove 15e is formed to rotate counterclockwise around the axis CL15 of the first shaft body 15, from the grinding fluid introduction side IN to the discharge side OUT (dummy line Ln).

[0051] As shown in Figure 4(a), the multiple large-diameter sections 15c are arranged with a gap G between them in the X direction. Furthermore, the multiple large-diameter sections 15c are configured so that their outer diameter gradually decreases from the grinding fluid introduction side IN to the discharge side OUT. That is, the outer diameter of the large-diameter section 15c located furthest towards the introduction side IN (the outer diameter of the envelope connecting the radially outer sides of the convex sections 15d) is D5, while the outer diameter of the large-diameter section 15c located furthest towards the discharge side OUT is D6, which is smaller than D5.

[0052] Furthermore, the outer diameter of the large-diameter portion 15c in the pivoting portion 15b is defined such that the outer circumference is in contact with or close to the inner surface of the peripheral wall surrounding the first space 100a, or with a small gap between them.

[0053] Furthermore, the end face 15g of the large-diameter portion 15c, which is located furthest towards the discharge side (OUT), abuts against the surrounding edge of the first introduction portion 102f in the discharge-side casing 102 without any gaps, while the swivel-providing portion 15b is housed in the first space 100a of the intermediate casing 100. As a result, the first shaft body 15 is held without any rattle inside the space 101b of the receiving-side casing 101 and the first space 100a of the intermediate casing 100.

[0054] The first shaft body 15 has the configuration described above. The second shaft body 16 differs from the first shaft body 15 in the configuration of the helical groove formed in the large diameter portion. Specifically, as described above, the first shaft body 15 has a helical groove 15e formed to rotate counterclockwise around the axis CL 15, whereas the second shaft body 16 has a helical groove formed to rotate clockwise around the axis. Except for this point, the second shaft body 16 has the same configuration as the first shaft body 15.

[0055] 4. Swirling direction of the grinding fluid introduced into the discharge casing 102 The swirling direction of the grinding fluid introduced into the first inlet 102f and the second inlet 102g of the discharge-side casing 102 will be explained with reference to Figure 5.

[0056] As described above, the grinding fluid introduced into the first space 100a of the intermediate casing 100 is guided by the helical groove 15e of the first shaft 15, which is formed to rotate to the left, and is given a direction of flow to rotate to the left. On the other hand, the grinding fluid introduced into the second space 100b is guided by the helical groove of the second shaft 16, which is formed to rotate to the right, and is given a direction of flow to rotate to the right.

[0057] In the intermediate casing 100, the first space 100a and the second space 100b are separated by a partition wall 100c. Therefore, the grinding fluid traveling through the first space 100a and the grinding fluid traveling through the second space 100b do not mix and are introduced directly into the first inlet 102f and the second inlet 102g of the discharge-side casing 102. Thus, as shown in Figure 5, the grinding fluid introduced into the first inlet 102f swirls to the left (FLL), and the grinding fluid introduced into the second inlet 102g swirls to the right (FLR).

[0058] 5. Configuration of the discharge side casing 102 The configuration of the discharge-side casing 102 will be explained using Figures 6 and 7. Figure 6 is a cross-sectional view showing the configuration of the section along line VI-VI in Figure 5, and Figure 7 is a cross-sectional view showing the configuration of the section along line VII-VII in Figure 6.

[0059] As shown in Figure 6, the discharge-side casing 102 has a first connecting passage 102h that connects the first inlet 102f to the connection part 102a to which the first nozzle 11 is connected, and a second connecting passage 102i that connects the second inlet 102g to the connection part 102c to which the third nozzle 13 is connected.

[0060] The first connecting passage 102h extends linearly along the X direction from the narrowest X-direction end of the funnel-shaped first introduction section 102f toward the end face 102d and is connected to the connecting section 102a. The second connecting passage 102i extends linearly along the X direction from the narrowest X-direction end of the funnel-shaped second introduction section 102g toward the end face 102d and is connected to the connecting section 102c.

[0061] In this embodiment, the first connecting passage 102h is smoothly connected to the first introduction section 102f without any radial steps, and the second connecting passage 102i is smoothly connected to the second introduction section 102g without any radial steps.

[0062] In this embodiment, a left-swirling flow connection path 102m is formed by combining the first inlet 102f and the first connecting path 102h, and a right-swirling flow connection path 102n is formed by combining the second inlet 102g and the second connecting path 102i.

[0063] Inside the discharge-side casing 102, a connecting passage 102j is formed that extends linearly in the Y direction and connects the first connecting passage 102h and the second connecting passage 102i. The connecting passage 102j is formed to connect the intermediate portions of the first connecting passage 102h and the second connecting passage 102i in the X direction. A portion of the left-swirling flow from the first connecting passage 102h and a portion of the right-swirling flow from the second connecting passage 102i flow into the connecting passage 102j.

[0064] As shown in Figure 7, a third connecting passage 102k is formed inside the discharge-side casing 102, extending linearly in the Z direction perpendicular to the direction in which the connecting passage 102j extends, and connecting the connecting passage 102j to the connecting portion 102b to which the second nozzle 12 is connected. The third connecting passage 102k is smoothly connected to the connecting passage 102j without any radial steps.

[0065] Furthermore, inside the discharge-side casing 102, a reservoir 102l is formed in the portion opposite to the side to which the third connecting passage 102k in the Z direction is connected, and which is connected to the connecting passage 102j.

[0066] In this embodiment, the left-swirling flow and the right-swirling flow entering in the connecting passage 102j collide and mix to generate a non-swirling flow, which is then guided to the connection section 102b in the third connecting passage 102k. That is, the combination of the connecting passage 102j and the third connecting passage 102k in this embodiment constitutes a non-swirling flow connecting passage (non-swirling flow generation section) 102p.

[0067] While the reservoir section 102l is not an essential component in the non-swirling flow generation section, it is desirable to include it to ensure sufficient mixing after a portion of the left-swirling flow and a portion of the right-swirling flow collide in the connecting passage 102j. In other words, it is a desirable configuration for removing the swirling properties of the grinding fluid and making it non-swirling before it is sent to the third connecting passage 102k.

[0068] Furthermore, the accumulation section 102l is a desirable configuration for converting the direction of travel of the non-swirling flow formed by collision and mixing in the connecting passage 102j to a direction (Z direction) perpendicular to the direction in which the connecting passage 102j extends (Y direction).

[0069] 6. Spraying grinding fluid onto the grinding wheel 21 The injection of grinding fluid onto the grinding wheel 21 using the grinding fluid injection device 1 having the above configuration will be explained with reference to Figure 8. Figure 8 is a front view of the contact start point P from the opposite side of the grinding area perpendicular to the rotation axis Ax21 of the grinding wheel 21, when the contact start point P is the upstream end in the direction of rotation of the grinding wheel 21 (arrow A1) within the grinding area of ​​the grinding wheel 21 relative to the workpiece 500 during grinding (see Figure 1).

[0070] As explained using Figure 1, each of the nozzles 11 to 13 has a flexible tube 11b, 12b, or 13b that is pliable. Therefore, it is possible to set each nozzle 11 to 13 in the following position.

[0071] As shown in Figure 8, the second nozzle 12 can assume a position in which it can inject a jet stream JS2, which consists of a non-swirling flow, onto the grinding surface 21a of the grinding wheel 21 and its surroundings at the contact initiation point P.

[0072] Furthermore, the first nozzle 11 can assume a posture that allows it to inject a jet stream JS1, which is composed of a left-swirling flow FLL, into the left corner 21d, which is the boundary between the left side surface 21b of the grinding wheel 21 and the grinding surface 21a of the grinding wheel 21, and its surrounding area at the contact initiation point P.

[0073] Furthermore, the third nozzle 13 can assume a posture that allows it to inject a right-swirling flow FLR into the right corner 21e and its surrounding area, which is the boundary between the right side surface 21c and the grinding surface 21a of the grinding wheel 21 at the contact initiation point P.

[0074] 7. Effects In the grinding fluid spraying device 1 according to this embodiment, a left-swirling flow FLL jet JS1 is sprayed from the first nozzle 11 to the left corner 21d of the grinding wheel 21 and its surroundings, and a right-swirling flow FLR jet JS3 is sprayed from the third nozzle 13 to the right corner 21e of the grinding wheel 21 and its surroundings. As a result, sufficient grinding fluid can be supplied to both corners 21d and 21e of the grinding surface 21a at the contact start point P. Specifically, in the grinding fluid spraying device 1, by spraying the left-swirling flow FLL to the left corner 21d, a portion of the jet JS1 is directed from the left corner 21d to the grinding surface 21a, and by spraying the right-swirling flow FLR to the right corner 21e, a portion of the jet JS3 is directed from the right corner 21e to the grinding surface 21a. Therefore, these wrap-around mechanisms allow for sufficient grinding fluid to be supplied to the vicinity of both corners 21d and 21e on the grinding surface 21a, and also prevent the grinding fluid sprayed from the second nozzle 12 onto the grinding surface 21a from escaping outward in the width direction of the grinding wheel 21 from both corners 21d and 21e, due to the respective portions of the ejected flows JS1 and JS3 that wrap around from both corners 21d and 21e.

[0075] Furthermore, since the grinding fluid spraying device 1 is configured to spray a non-swirling flow onto the grinding surface 21a from the second nozzle 12, it is possible to suppress the grinding fluid sprayed onto the grinding surface 21a from becoming biased to one side in the width direction of the grinding surface 21a. In other words, when spraying a left-swirling flow or a right-swirling flow onto the grinding surface 21a, there is a concern that the grinding fluid on the grinding surface 21a will become biased in the swirling direction. However, since a non-swirling flow is sprayed onto the grinding surface 21a, the bias of the grinding fluid on the grinding surface 21a can be suppressed.

[0076] Furthermore, in the grinding fluid injection device 1 according to this embodiment, a non-swirling flow connection passage 102p (connecting passage 102j and third connection passage 102k) is formed in the discharge-side casing 102, and a part that generates non-swirling flow (non-swirling flow generation section) is configured by the non-swirling flow connection passage 102p, so that non-swirling flow can be generated with a simple configuration. Therefore, it is possible to suppress the increase in size of the device 1 and suppress the increase in device costs.

[0077] Furthermore, the grinding fluid injection device 1 has a configuration (non-swirling flow generation unit) that generates a non-swirling flow by colliding and mixing a portion of the left-swirling flow FLL and a portion of the right-swirling flow FLR within the discharge-side casing 102. Therefore, the overall configuration of the device can be simplified compared to the case where a non-swirling flow is generated without using a portion of the left-swirling flow and a portion of the right-swirling flow. Thus, the grinding fluid injection device 1 can suppress an increase in the size of the device and an increase in the cost of the device.

[0078] Furthermore, in the grinding fluid injection device 1 according to this embodiment, a reservoir 102l is provided in the discharge-side casing 102, so that a portion of the left-swirling flow FLL and a portion of the right-swirling flow FLR collide and are then thoroughly mixed in the reservoir 102l. Therefore, the grinding fluid injection device 1 can reliably generate a non-swirling flow within the discharge-side casing 102.

[0079] Furthermore, in the grinding fluid injection device 1, the direction of travel of the non-swirling flow formed by collision mixing in the connecting passage 102j can be converted by the accumulation section 102l to the Z direction in which the third connecting passage 102k extends. Therefore, in the grinding fluid injection device 1, the non-swirling flow generated in the connecting passage 102j can be guided with high efficiency to the connection section 102b of the second nozzle 12.

[0080] Furthermore, in the grinding fluid spraying device 1 according to this embodiment, a left-swirling flow generation unit 17 is formed by a first shaft body 15 housed in a first space 100a of the intermediate casing 100 and having a helical groove portion 15e provided to swirl to the left, and a right-swirling flow generation unit 18 is formed by a second shaft body 16 housed in a second space 100b of the intermediate casing 100 and having a helical groove portion provided to swirl to the right. Therefore, the grinding fluid introduced into the first space 100a flows along the helical groove portion 15e of the first shaft body 15, resulting in a left-swirling flow, and the grinding fluid introduced into the second space 100b flows along the helical groove portion of the second shaft body 16, resulting in a right-swirling flow. In this way, the grinding fluid spraying device 1 can generate both left-swirling and right-swirling flows with a simple configuration.

[0081] Furthermore, in the grinding fluid injection device 1 according to this embodiment, the first space 100a is formed to extend from the coupling side of the receiving casing 101 to the coupling side of the discharge casing 102 in such a way that the cross-sectional size gradually decreases. As is clear from Bernoulli's theorem, the static pressure of the grinding fluid introduced into the first space 100a decreases as it moves toward the discharge side. In this case, by configuring the first space 100a so that the static pressure of the grinding fluid reaches the saturated vapor pressure, a cavitation phenomenon can be induced in the grinding fluid.

[0082] Furthermore, in the grinding fluid injection device 1, the first shaft body 15 has a plurality of protrusions 15d, so that a network of flow channels is formed on the circumferential surface of the first shaft body 15 by these multiple protrusions 15d. Therefore, the grinding fluid introduced into the first space 100a repeatedly splits and merges through the network of flow channels of the first shaft body 15, generating numerous fine vortices through a flip-flop phenomenon and producing fine bubbles (fine bubbles less than 100 μm).

[0083] The second space 100b of the intermediate casing 100 is also formed so that its cross-sectional size gradually decreases from the coupling side of the receiving casing 101 to the coupling side of the discharge casing 102. As the grinding fluid introduced into the second space 100b moves toward the discharge side, the static pressure decreases, making it possible to cause cavitation in the grinding fluid.

[0084] Furthermore, since the second shaft body 16, like the first shaft body 15, has multiple protrusions, the grinding fluid introduced into the second space 100b travels through the mesh-like channels formed on the circumferential surface of the second shaft body 16, repeatedly splitting and merging, generating numerous minute vortices through a flip-flop phenomenon, and thus generating fine bubbles.

[0085] As described above, in the grinding fluid spraying device, the left-swirling flow, right-swirling flow, and non-swirling flow each contain fine bubbles, so the sprayed grinding fluid adheres to the grinding surface of the grinding wheel (coander effect), and when it collides with the grinding surface, the bubbles burst easily (cavitation phenomenon), allowing the grinding wheel to be cooled and cleaned.

[0086] Furthermore, in the grinding fluid spraying device 1 according to this embodiment, a flow rate adjustment valve 14 is provided in the non-swirling flow path, so the flow rate (amount of spray) of the non-swirling flow sprayed can be adjusted according to the grit size of the grinding wheel 21. That is, when using a grinding wheel 21 with a larger grit size, hydroplaning is more likely to occur compared to when using a grinding wheel 21 with a smaller grit size, even if the same flow rate of grinding fluid is supplied to the grinding surface 21a. In order to prevent hydroplaning, it is preferable to use a smaller amount of grinding fluid sprayed onto the grinding surface 21a when using a grinding wheel 21 with a larger grit size than when using a grinding wheel 21 with a smaller grit size. Therefore, by providing a flow rate adjustment valve 14 that can adjust the amount of grinding fluid sprayed onto the grinding surface 21a in the grinding fluid spraying device 1, the flow rate can be adjusted according to the grit size of the grinding wheel 21, and the occurrence of hydroplaning can be suppressed.

[0087] As described above, the grinding fluid spraying device 1 according to this embodiment can supply a sufficient amount of grinding fluid to the corners 21d and 21e in the width direction of the grinding surface 21a of the grinding wheel 21.

[0088] [Differentiation] In the above embodiment, the grinding fluid sprayed from the grinding fluid spraying device 1 contains fine bubbles (bubbles as defined in ISO 20480-1). However, in the present invention, it is not essential that the sprayed grinding fluid contains fine bubbles.

[0089] Furthermore, in the grinding fluid spraying device 1 according to the above embodiment, the left-swirling flow generation unit 17 and the right-swirling flow generation unit 18 are configured in the intermediate casing 100. However, in the present invention, the left-swirling flow generation unit and the right-swirling flow generation unit may be configured in separate casings spaced apart from each other.

[0090] Furthermore, in the grinding fluid spraying device 1 according to the above embodiment, each nozzle 11 to 13 has a flexible tube 11b, 12b, and 13b, which allows the position of the nozzles 11 to 13 to be freely set. However, in the present invention, it is not essential that the nozzles have flexible tubes. For example, multiple tube materials may be connected with a joint member such as a universal joint so that they can assume various positions.

[0091] Furthermore, in the grinding fluid spraying device 1 according to the above embodiment, the first shaft body 15 and the second shaft body 16 are provided with a rhombic-shaped protrusion 15d when viewed from the radially outer side. However, the shape of the protrusion when viewed from the radially outer side is not limited to a rhombic shape. For example, it may be a rounded quadrilateral, an oval, or a polygon with five or more sides.

[0092] Furthermore, in the grinding fluid injection device 1 according to the above embodiment, a non-swirling flow is generated by colliding and mixing a portion of the left-swirling flow and a portion of the right-swirling flow in the non-swirling flow connection passage 102p. However, in the present invention, generating a non-swirling flow by colliding and mixing a portion of the left-swirling flow and a portion of the right-swirling flow is not necessarily an essential configuration. For example, the grinding fluid taken in from the grinding fluid storage tank 2, which is the supply source, can be used as is. [Explanation of Symbols]

[0093] 1. Grinding fluid spraying device 2. Grinding fluid storage tank (supply source) 10 Main unit of the device 11. Nozzle No. 1 12. Second nozzle 13. Third Nozzle 14 Flow control valve 15. First Axis Body 15d convex part 15e Spiral groove 16. Second Axis Body 17 Left swirl flow generation section 18 Right swirl flow generation section 20 Grinding equipment 21 Sharpening stones 21a Grinding surface (outer surface) 21b Left side 21c Right side 21d left corner 21e Right corner 100 Intermediate casing 101 Receiving casing 102 Discharge side casing 102j connecting route 102m Left swirl flow connection path 102n Right-hand swirl flow connection path 102p Non-swirling flow connection path (non-swirling flow generation part) P Contact start point

Claims

1. A grinding fluid spraying device that sprays grinding fluid onto a disc-shaped grinding wheel in a grinding machine, A left-swirling flow generation unit receives the grinding fluid from a supply source and generates a left-swirling flow of the grinding fluid as it moves while swirling to the left, A right-handed swirling flow generation unit receives the grinding fluid from the supply source and generates a right-handed swirling flow of the grinding fluid as it moves while swirling to the right, A non-swirling flow generation unit generates a non-swirling flow of the grinding fluid that moves without swirling, A first nozzle that injects the remaining portion of the left-swirling flow, The second nozzle that injects the non-swirling flow, A third nozzle that injects the remaining portion of the aforementioned right-swirling flow, Equipped with, When the grinding process is performed, the contact starting point is defined as the upstream end of the grinding wheel's grinding area relative to the workpiece in the direction of rotation of the grinding wheel, and when this contact starting point is viewed from the front from the opposite side of the grinding area in a direction perpendicular to the rotation axis of the grinding wheel, The first nozzle is configured to be able to take a position in which the remaining portion of the left-swirling flow can be injected into the left corner portion and its surrounding area, which is the boundary between the left side surface of the grinding wheel and the grinding surface of the grinding wheel at the point where contact begins. The second nozzle is configured to be able to assume a position in which the non-swirling flow can be injected onto the grinding surface and its surroundings at the contact initiation point. The third nozzle is configured to be able to take a position in which the remaining portion of the right-swirling flow can be injected into the right corner portion, which is the boundary between the right side surface of the grinding wheel and the grinding surface at the contact initiation point, and its surrounding area. Grinding fluid spraying device.

2. The non-swirling flow generation unit generates the non-swirling flow by colliding and mixing a portion of the left-swirling flow with a portion of the right-swirling flow. The grinding fluid spraying device according to claim 1.

3. The left-swirling flow generation unit, the right-swirling flow generation unit, and the non-swirling flow generation unit are formed within a casing which is comprised of a receiving-side casing having a receiving section for receiving the grinding fluid from the supply source, a discharge-side casing to which the first nozzle, the second nozzle, and the third nozzle are connected, and an intermediate casing connecting the receiving-side casing and the discharge-side casing. The discharge-side casing includes a left-swirling flow connection path that guides a portion of the left-swirling flow generated in the left-swirling flow generation unit to the connection of the first nozzle, a right-swirling flow connection path that guides a portion of the right-swirling flow generated in the right-swirling flow generation unit to the connection of the third nozzle, and a non-swirling flow connection path that connects the left-swirling flow connection path and the right-swirling flow connection path, and guides the non-swirling flow generated by collision mixing at the connection portion to the connection of the second nozzle. The non-swirling flow generation unit is configured by a non-swirling flow connection path formed in the discharge-side casing. The grinding fluid spraying device according to claim 2.

4. The non-swirling flow connection path includes a connecting path that connects the left-swirling flow connection path and the right-swirling flow connection path, and a connecting path that is connected to the connecting path and extends to the connection portion of the second nozzle in a direction intersecting the direction in which the connecting path extends. The discharge-side casing is connected to the connecting passage and further has a reservoir portion provided on the side opposite to the connecting passage in the direction in which the connecting passage extends, for temporarily holding the non-swirling flow. The grinding fluid spraying device according to claim 3.

5. The intermediate casings are separated from each other by partition walls and each has a first space and a second space that extend from the coupling side of the receiving casing to the coupling side of the discharge casing such that the cross-sectional size gradually decreases. The left-handed swirling flow generating unit has a first shaft body housed in the first space and having a helical groove formed on its outer circumference to swirl leftward from the coupling side of the receiving casing toward the coupling side of the discharge casing. The right-handed swirling flow generating unit is housed in the second space and has a second shaft body having a helical groove formed on its outer circumference to swirl to the right from the coupling side of the receiving casing to the coupling side of the discharge casing. The grinding fluid spraying device according to claim 3.

6. Each of the first shaft and the second shaft has a plurality of protrusions formed between adjacent helical grooves in the circumferential direction, which have a rhombic shape when viewed from the radially outer side in plan view. The plurality of protrusions are arranged with gaps between them in the direction from the coupling side of the receiving casing toward the coupling side of the discharging casing. The grinding fluid spraying device according to claim 5.

7. The system further includes a flow control valve provided between the non-swirling flow generation unit and the injection port of the second nozzle in the flow path of the non-swirling flow, for adjusting the injection flow rate of the non-swirling flow. A grinding fluid spraying device according to any one of claims 1 to 6.

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