Gland rotation restriction plate structure for rotational valve and ball valve

Abstract

To provide a gland rotation restriction plate structure for a rotational valve which can prevent a loosening of a gland and projectile of a stem without processing the rotational valve, restrict a rotation of the gland in a state where a packing is fastened at optimal torque, and minimize the loosening of the gland after being fastened.SOLUTION: A rotation restriction plate 10 is provided in which a gland 5 is screwed and fixed to an upper opening 13 of a shaft cylindrical part 11 formed on a body 2 of a rotational valve 1, and which is installed to the gland to restrict a rotation thereof. The body has a stopper part 15, and the rotation restriction plate has at least a base part 30, a stem hole 31, a detent part 32, and a gland locking part 33. When installing the rotation restriction plate to the gland, the gland locking part is locked with the gland such that the detent part is not fixed to a position in a rotational direction with respect to the stopper part, and a rotational operation is accepted until the detent part comes into contact with the stopper part in a loosening rotation direction of the gland.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a gland rotation restriction plate for rotary valves, such as ball valves, that prevents loosening of the gland used in the rotary valves and restricts its rotation, and to a ball valve. [Background technology]

[0002] Conventionally, in rotary valves such as ball valves, a structure has been generally used in which a gasket for sealing the shaft mounting is housed within the shaft mounting portion, and this gasket is pressed into the gland to seal and ensure airtightness within the shaft mounting portion. In rotary valves with this type of shaft mounting structure, the gland is prone to gradually loosening due to the repeated application of rotational torque from the stem when the operating part is opened and closed, and this loosening of the gland can gradually deteriorate the sealing performance of the packing. In response to this, a valve is known in which the rotation of the gland is forcibly restricted to prevent unnecessary rotation and thereby prevent loosening in order to maintain the sealing performance of the packing.

[0003] For example, Patent Document 1 discloses a valve equipped with this type of structure for restricting gland rotation. This valve has a gland (packing gland) fitted between the valve stem and valve body, a rotation-preventing fitting covering the gland, and a locking ring between the rotation-preventing fitting and a hexagonal head formed on the top of the gland. A notch is formed in the bottom of the locking ring, and this notch is designed to be engageable with a protrusion on the valve body. The locking ring also has a hexagonal bore formed on its inner periphery, into which the head of the gland on the top of the gland can be fitted.

[0004] In the above valve, the gland is screwed into the body and presses against the packing housed in the mounting portion. The head of the gland is then fitted into the upper bore of the locking ring, and the locking ring is attached to the body with the protrusion on the valve body engaging the notch at the bottom of the locking ring. This positions the gland in the body and prevents it from rotating relative to the mounting portion.

[0005] Furthermore, a structure is known in which a rotation-restricting plate is used to prevent rotation of the gland instead of the locking ring described in Patent Document 1. In this case, the restricting plate is provided with, for example, a through-hole for passing the stem therethrough when the stem is attached to the mounting portion, a locking piece that locks onto the hexagonal head of the gland, and a protruding portion that locks onto the mounting portion side of the body. The protruding portion is provided, for example, with two protruding pieces that can sandwich and lock onto a stopper piece that is integrally formed with the mounting portion and that restricts rotation of the handle.

[0006] The regulating plate is attached between the body and the gland with the stem passing through the through-hole, the protruding piece engaging with the stopper piece of the body, and the engaging piece engaging with the head of the gland. This positions the gland on the body through the regulating plate, preventing it from rotating relative to the mounting part. In addition, to maintain the regulating plate in the centering direction of the mounting part, a holding piece is provided hanging down from the outer periphery of the regulating plate, and the holding piece abuts against the outer periphery of the mounting part, thereby positioning the regulating plate relative to the mounting part. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Utility Model Application Publication No. 50-68929 Summary of the Invention [Problem to be solved by the invention]

[0008] In the valve of the former Patent Document 1, a protrusion must be provided in advance on the body to engage the notch in the locking ring, and if the locking ring of Patent Document 1 is to be used on an existing valve to restrict rotation of the gland, a new protrusion must be machined and formed on the body. In either case, the protrusion must be formed with high dimensional precision in order to ensure that the notch in the locking ring fits securely into the protrusion and that the locking ring can be attached to the body in an unrotatable state.

[0009] Furthermore, if a gap is created between the convex portion and the notch, or between the hexagonal bore and the head of the gland, and the gland is secured in place by the locking ring, repeated rotation of the stem may cause the gland to loosen, which could cause the stem to move out of the body. Therefore, the locking ring must have a high-precision cutout and hexagonal bore, just like the convex portion on the body.

[0010] In addition, when the locking ring is fitted to the body while aligning the notch and the protrusion, its hexagonal bore is set to a specific orientation, and the orientation of this bore cannot be adjusted. Therefore, when the gland is screwed into the body, the hexagonal head must be securely fitted into the locking ring's inner tube and the gland head must be aligned in a specific direction to prevent the gland from rotating relative to the locking ring. Therefore, the gland must be screwed in while adjusting the degree of screw-in. However, if the degree of screwing of the packing gland is changed, the packing may be overtightened or undertightened, preventing it from exerting its optimal pressing force. Not only will this result in insufficient sealing, but overtightening may also damage the threaded joint between the packing gland and the body, or undertightening may make the packing gland more likely to loosen.

[0011] On the other hand, in the case of the latter structure using a regulating plate, if the body is formed by casting or the like and has low processing accuracy, errors will occur in the dimensional accuracy of the stopper piece of the body, and due to these errors, there is a possibility that play will occur between the protruding piece of the regulating plate and the stopper piece when the regulating plate is attached to the mounting part. In addition, if the through hole is formed with a hole diameter that is excessively large compared to the outer diameter of the stem in order to reliably attach the regulating plate to account for dimensional errors in the mounting part, the play of the regulating plate relative to the mounting part will become even greater. If the gland is not sufficiently regulated by the regulating plate due to this play, repeated rotation of the stem may cause the gland to loosen and come out, or the stem to pop out.

[0012] Furthermore, when screwing the gland into the body, the orientation of the hexagonal head needs to be aligned with the position of the locking piece of the regulating plate after it has been attached to the mounting portion, so it is necessary to adjust the degree to which the gland is screwed into the body, as in the case of Patent Document 1. This makes it difficult to ensure that the gland presses the packing optimally, and it may be difficult to obtain sufficient tightening torque when pressing the packing, or the tightening torque may be insufficient, making it difficult to achieve sufficient sealing performance. As described above, in a structure in which the head of the gland is fixed to the body side using a locking ring or a restricting plate, etc., and the rotation of the gland relative to the body is completely restricted, various problems can arise.

[0013] The present invention was developed to solve the above problems, and its purpose is to provide a gland rotation restriction plate structure for a rotary valve that can prevent loosening of the gland and protrusion of the stem without processing the rotary valve, restrict the rotation of the gland when the packing is tightened with an optimal torque, and minimize loosening of the gland after tightening. [Means for solving the problem]

[0014] In order to achieve the above-mentioned object, the invention of claim 1 is a structure in which a gland is screwed and fixed into the upper opening of a tubular portion formed in the body of a rotary valve, and which is equipped with a rotation restriction plate that is attached to the gland to restrict its rotation, wherein the body has a stopper portion that restricts the rotational range of the handle that rotates the stem, and the rotation restriction plate has at least a base portion that is placed on the gland, a stem hole that is passed through the center position of the base portion, a rotation prevention portion that protrudes outer circumferentially from the base portion and can abut the stopper portion, and a gland engagement portion that engages with the gland so that the rotation restriction plate can rotate together with the gland, and when the rotation restriction plate is attached to the gland, the rotation prevention portion is not fixed in position in the rotational direction relative to the stopper portion, and the gland engagement portion is engaged with the gland so that rotation movement is allowed in the rotation direction in which the gland loosens until it comes into contact with the stopper portion.

[0015] The invention according to claim 2 is a structure in which a gland is screwed and fixed to an upper opening of a tubular shaft portion formed in the body of a rotary valve, and a rotation restriction plate is attached to the gland to restrict its rotation, the gland having a regular polygonal portion at a portion exposed at the upper part of the body, the body having a stopper portion that restricts the rotation range of a handle that rotates the stem, and the rotation restriction plate has at least a base portion placed on the gland, a stem hole that passes through the center of the base portion, a rotation stopper portion that protrudes from the base portion in the outer circumferential direction and can abut against the stopper portion, and the base The gland rotation restriction plate structure for a rotary valve comprises a gland engagement portion that protrudes outward from the stopper portion and holds one corner or side of the regular polygon portion of the gland, and when the rotation restriction plate is attached to the gland, the rotation restriction portion is positioned closest to the stopper portion on the side of the rotation direction in which the gland tightens relative to the stopper portion, and the corner or side of the regular polygon portion to be engaged by the gland engagement portion is selected so that the rotation angle until the rotation restriction portion contacts the stopper portion in the rotation direction in which the gland loosens is less than 1 / 2 of the central angle of the regular polygon portion.

[0016] The invention of claim 3 is a ground rotation restriction plate structure for a rotary valve, in which the rotation restriction plate has two anti-rotation portions, and the angle at which rotation is possible from when one anti-rotation portion abuts the stopper portion until the other anti-rotation portion abuts the stopper portion is less than 1 / 2 of the central angle of the regular polygon portion.

[0017] The invention of claim 4 is a ground rotation restricting plate structure for a rotary valve in which the ground engagement portion is formed by two protruding pieces that protrude radially from the base portion approximately parallel to each other and hang down toward the ground, and these protruding pieces hold the corners of a regular polygonal portion or engage one side to hold it in place.

[0018] The invention according to claim 5 is a gland rotation restriction plate structure for a rotary valve in which the stem hole is provided with a diameter slightly larger than the diameter of the stem.

[0019] The invention of claim 6 is a rotary valve that has a ball with a through hole rotatably arranged within the body, a stem that rotates the ball is arranged in the axially mounted cylindrical portion, and the upper part of the stem is rotated with a handle. [Effects of the Invention]

[0020] According to the invention of claim 1, a rotation restriction plate is attached to the gland without machining the rotary valve, and this rotation restriction plate restricts the rotation of the gland, thereby maintaining the shaft seal provided by the packing. Furthermore, when attaching the rotation restriction plate to the gland, the rotation stopper is not fixed in the rotational direction relative to the stopper of the body, and rotation is allowed until it contacts the stopper. This means that the rotation restriction plate is not fixed in position relative to the gland, and can be attached at any rotational position. This allows the gland to tighten the packing with the optimal torque, so the rotation restriction plate can be attached to the gland even if the gland's rotational position is not constant. As a result, the rotation restriction plate can be attached to the gland in a state where the packing's sealing performance is most effectively exerted, and the high sealing performance of the packing can be maintained while restricting the gland's rotation with this rotation restriction plate. When the gland tries to rotate in the loosening direction due to rotational torque from the stem, the anti-rotation portion comes into contact with the stopper, and the gland only loosens by the rotation angle from the initial position until the anti-rotation portion abuts the stopper portion, thereby reliably preventing the gland from loosening too much and the stem from popping out.

[0021] According to the invention of claim 2, a rotation restriction plate is attached to the gland without machining the rotary valve, and this rotation restriction plate restricts the rotation of the gland, thereby maintaining the shaft seal provided by the packing. Furthermore, when attaching the rotation restriction plate to the gland, the gland engagement portion selects and holds the corner or side of the gland's regular polygonal portion, while the rotation restriction portion of the rotation restriction plate is designed to abut against the stopper portion of the rotary valve body. This allows the gland to be tightened with the optimal torque, allowing the rotation restriction plate to be attached to the gland while the packing's sealing performance is maximized, and this rotation restriction plate restricts the gland's rotation, maintaining the packing's high sealing performance. When the gland attempts to rotate in the loosening direction due to rotational torque from the stem, the rotation restriction portion contacts the stopper portion, limiting the rotation angle to less than half the central angle of the regular polygonal portion. This minimizes loosening of the gland after tightening, reliably preventing excessive loosening of the gland and stem protrusion.

[0022] According to the invention of claim 3, the rotation restricting plate can be easily aligned and attached to the gland with the orientation of the rotation restricting plate aligned so that the stopper portion of the body is located between the two anti-rotation portions. In this case, the range of rotation of the two anti-rotation portions until they contact the stopper portion is equal to or less than half the central angle of the regular polygonal portion of the gland. Therefore, regardless of the orientation of the regular polygonal portion of the gland after fastening, the rotation restricting plate can be positioned so that the stopper portion is located between the two anti-rotation portions while holding one corner or side of the regular polygonal portion with the gland engaging portion, and the rotation restricting plate can be attached in a state where rotation of the gland is reliably restricted.

[0023] According to the invention of claim 4, when attaching the rotation restriction plate to the ground, it can be easily attached by simply placing it over the ground from above, with the two protruding pieces holding the corners or one side of the regular polygonal part.After attachment, the rotation restriction plate rotates reliably together with the ground as the protruding pieces are held to the ground, allowing the rotation restriction plate to perform its function.

[0024] According to the invention of claim 5, the stem hole is made slightly larger in diameter than the stem, and the clearance between this stem hole and the stem is set to an extent that the ground engagement portion does not come loose from holding the corner or side of the regular polygonal portion. This prevents the rotation restriction plate from shifting position or coming off the ground, and makes it possible to rotate the rotation restriction plate and the ground together, thereby reliably restricting the rotation of the ground.

[0025] According to the invention of claim 6, a ball valve with a screw-type gland can be provided that can maintain the shaft seal of the packing by restricting the rotation of the gland through a rotation restriction plate without processing the body. Moreover, the gland can be tightened with the optimal torque, and the rotation restriction plate can be attached to the gland while the packing's sealing performance is maximized. This rotation restriction plate restricts the rotation of the gland, maintaining the functionality of the packing. When the gland tends to rotate in the loosening direction due to rotational torque from the stem, etc., by minimizing the loosening of the gland after tightening, it is possible to reliably prevent the gland from loosening and the stem from popping out. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a longitudinal cross-sectional view showing an embodiment of a rotary valve to which the gland rotation restriction plate structure of the rotary valve of the present invention is applied. [Figure 2] 1A is a plan view of the rotation restricting plate, FIG. 1B is a front view of FIG. 1A, and FIG. 1C is a right side view of FIG. 1B. [Figure 3] 2 is an enlarged perspective view showing the vicinity of a barrel portion of the rotary valve of FIG. 1. FIG. [Figure 4] 10A and 10B are schematic diagrams illustrating the rotational states of the gland and the rotation restricting plate. DETAILED DESCRIPTION OF THE INVENTION

[0027] The following describes in detail the embodiments of the gland rotation restriction plate structure for a rotary valve and a ball valve according to the present invention with reference to the drawings. Figure 1 shows a longitudinal cross-sectional view of an embodiment of a rotary valve to which the gland rotation restriction plate structure of the present invention is applied, Figure 2 shows the rotation restriction plate, and Figure 3 shows an enlarged perspective view of the rotary valve in Figure 1 near the shaft mounting portion.

[0028] In Figure 1, the rotary valve 1 provided with the gland rotation restriction plate structure of the present invention is composed of, for example, a ball valve whose flow path can be opened and closed by rotating it approximately 90°. This ball valve 1 has an existing general configuration including a body 2, a ball 3, a stem 4, a gland 5, a handle 6, a cylindrical gasket 7 for shaft sealing, and two sealing ball seats 8, and a rotation restriction plate 10 is attached to this ball valve 1.

[0029] In the ball valve 1, the body 2 comprises a body portion 2a and a cap portion 2b, which are screwed together to form a single body. A roughly cylindrical axial mounting portion 11 is formed at the top of the body 2. A ball 3 having a through hole 3a is rotatably mounted within the body 2 through ball seats 8, 8 on both sides. A stem 4 for rotating the ball 3 is inserted into the axial mounting portion 11.

[0030] A storage section 12 having a larger diameter than the stem 4 is provided on the inner peripheral side of the mounting tube section 11, and a female screw 14 is formed to a predetermined depth on the upper opening 13 side of this storage section 12. A packing 7 is provided at the bottom side of the storage section 12 so that it can be stored therein, and a gland 5 for pressing the packing is attached to the top of this packing 7. A stopper portion 15 for restricting the range of rotation of the handle 6 is formed on the outer periphery of the upper mounting cylinder portion 11 so as to protrude above the upper opening 13 .

[0031] The gland 5 is formed in a generally cylindrical shape so that the stem 4 can be inserted into its inner periphery, and a male screw 16 that can be threaded into the female screw 14 is formed on the outer periphery on the attachment side to the tubular bearing portion 11. The gland 5 is provided with a regular polygon portion 20 that is a regular polygon in plan view in a portion above the male screw 16 and that is exposed at the top of the body 2 when the gland 5 is attached to the tubular bearing portion 11.

[0032] The regular polygonal portion 20 is formed so that the gland 5 can be tightened or loosened relative to the mounting tube portion 11 of the body 2 using a tightening tool (not shown), such as a wrench or a spanner. In this example, the regular polygonal portion 20 is formed as a regular hexagonal portion having a substantially regular hexagonal shape in a plan view. The outer shape of this regular hexagonal portion 20 is substantially the same as the head of a commonly used bolt, and its outer periphery has six sides 21 and six corners 22 formed between adjacent sides 21. The corners 22 are chamfered as in the head of a typical bolt. However, in the present invention, the corners between the sides 21, including such chamfered corners, are referred to as "corners." The corners 22 do not necessarily have to have pointed tips, as in this embodiment. In FIG. 4, when the regular polygonal portion 20 is formed by a regular hexagonal portion as described above, the central angle θ is 60°.

[0033] In the gland rotation restriction plate structure of the rotary valve of this embodiment, with the packing 7 stored in the storage section 12, the gland 5 is screwed and fixed into the upper opening 13 of the axially mounted cylindrical section 11 of the body 2 through the female screw 14 and the male screw 16, and a rotation restriction plate 10 is attached to the gland 5, so that the rotation of the gland 5 can be restricted by this rotation restriction plate 10.

[0034] As shown in FIG. 2, the rotation restricting plate 10 has at least a base portion 30, a stem hole 31, a rotation preventing portion 32, and a gland engaging portion 33. The base portion 30 is formed in a plate shape and has an outer shape that allows it to be placed on the top surface of the regular hexagonal portion (regular polygonal portion) 20 of the gland 5 fixed to the axially mounted cylindrical portion 11.

[0035] The stem hole 31 is formed to pass through approximately the center of the base portion 30, and its inner diameter φdh is set to be slightly larger than the diameter (outer diameter) φDs of the stem 4 so that the stem 4 can be inserted therein. More specifically, the stem hole 31 is preferably designed so that when the stem 4 is inserted into the stem hole 31, the clearance between them is very small so that the gland engagement portion 33 does not come loose from holding the corners 22 or sides 21 of the regular hexagonal portion 20 of the gland 5.

[0036] The anti-rotation portions 32 are formed on approximately the same plane as the base portion 30 and protrude in the outer circumferential direction thereof, and are provided so as to come into contact with the stopper portions 15 and restrict the rotation range of the gland 5 if the rotation restricting plate 10 rotates together with the gland 5 in accordance with the rotation of the stem 4 after the rotation restricting plate 10 is attached to the gland 5. In this embodiment, the anti-rotation portions 32 are provided at two locations on the rotation restricting plate 10.

[0037] In this case, the distance between the two anti-rotation portions 32 is set by a rotation angle α restricted by one anti-rotation portion 32 and the other anti-rotation portion 32. Specifically, this is the angle at which rotation is possible from the state in which one anti-rotation portion 32 abuts against the stopper portion 15 until the other anti-rotation portion 32 abuts against the stopper portion 15 when the rotation restricting plate 10 attempts to rotate due to the rotation of the gland 5, and the positional relationship of the two anti-rotation portions 32 is set so that this rotation angle α is equal to or less than half the central angle θ of 60° of the regular hexagonal portion (regular polygonal portion) 20, i.e., the rotation angle α is 30°.

[0038] 2 is set in advance, taking into consideration the angle due to the width of the stopper portion 15, so that the rotation angle α after the rotation restricting plate 10 is attached to the gland 5 is approximately 30°. That is, the angle β between the anti-rotation portions is set after adding the angle γ due to the width of the stopper portion 15 so that the rotation angle α from when one anti-rotation portion 32 abuts against the stopper portion 15 to when the other anti-rotation portion 32 abuts against the stopper portion 15 when the rotation restricting plate 10 tries to rotate together with the gland 5 due to the rotation of the gland 5 is 30°. In Figure 4, the angle γ formed by the width of the stopper portion 15 in this example is approximately 34°, so the rotation restriction plate 10 is pre-formed so that the angle β between the two anti-rotation portions is rotation angle α (30°) + angle γ (approximately 34°) = approximately 64°.

[0039] The ground engagement portion 33 is provided so as to be able to engage with the ground 5 so that the rotation restriction plate 10 can rotate together with the ground 5, and in this example, it protrudes in the outer circumferential direction from the base portion 30 and is formed so as to be able to hold one corner 22 or side 21 of the regular polygon portion 20 of the ground 5.

[0040] 2(a), the gland engagement portion 33 is formed by two protruding pieces that protrude from the base portion 30 in a generally parallel orientation at a position facing the rotation prevention portion 32 across the center of the rotation restriction plate 10 and that hang down toward the gland 5. These protruding pieces 33, due to their shape as described above, can attach the rotation restriction plate 10 to the gland 5 by sandwiching the corners 22 of the regular hexagonal portion (regular polygonal portion) 20 or by holding one side 21 in engagement with it. When attached to the gland 5 in this manner, the rotation restriction plate 10 can rotate together with the gland 5.

[0041] The handle 6 shown in Figures 1 and 3 has a mounting hole 40 formed on the side where it is attached to the stem 4, and this mounting hole 40 has a parallel two-faced portion 41. The handle 6 is attached to the stem 4 by passing the stem 4 through the mounting hole 40, and with a two-faced portion 42 formed parallel to the top of the stem 4 fitted into the parallel two-faced portion 41, via a nut 43 and a washer 44. In this way, the stem 4 is provided so that it can be rotated through the handle 6.

[0042] A notch 45 is formed on the base end side of the handle 6 over a range of 90° around the mounting hole 40, and restricting surfaces 46 are provided on both edges of this notch 45 to restrict the rotation angle of the stem 4 by operating the handle 6. The restricting surfaces 46 are provided so as to come into contact with and engage the stopper portion 15 of the body 2 when the handle 6 is rotated, thereby restricting the rotational movement of the stem 4 to a range of approximately 90°.

[0043] When a regular polygonal portion 20 is provided on the upper portion of the body 2, the regular polygonal portion 20 may have a shape other than a regular hexagon, and may be an equilateral triangle, a regular square, or a regular polygon having an octagon or more sides. When the regular polygonal portion 20 is a regular hexagon as in this embodiment, the shape is approximately the same as the shape of the head of a hexagonal bolt or hexagonal nut that is normally used, and therefore, it can be easily tightened or loosened using a general tightening tool such as a wrench or spanner.

[0044] The distance (angle β) between the two anti-rotation portions 32 can be set to any angle other than the above, and it is also possible to have only one anti-rotation portion 32, and to provide this single anti-rotation portion 32 so that it can abut against the stopper portion 15.

[0045] The rotary valve 1 provided with the gland rotation restricting plate structure for a rotary valve according to the present invention is not limited to a ball valve, but can be applied to various rotary valves such as a butterfly valve (not shown).

[0046] Next, the gland rotation restricting plate structure for a rotary valve of the present invention and the operation of the embodiment will be described together with the work of attaching the rotation restricting plate 10 to the ball valve (rotary valve) 1.

[0047] The rotation restriction plate 10 can be attached to the gland 5 without any processing of the existing ball valve 1, and when the handle 6 is attached, the nut 43 of the ball valve 1 is loosened and removed, and with the washer 44 and handle 6 removed, the rotation restriction plate 10 is attached while being positioned in a predetermined state relative to the gland 5 and stopper portion 15.

[0048] After the rotation restriction plate 10 is attached, the handle 6 is attached in a predetermined direction from above the rotation restriction plate 10, and the nut 43 is fastened and fixed to the top of the stem 4 via a washer 44, so that the rotation restriction plate 10 is attached together while being prevented from slipping out.

[0049] When the rotation restriction plate 10 is attached to the gland 5, the anti-rotation portion 32 is engaged with the gland engaging portion 33 so that the position of the anti-rotation portion 32 is not fixed relative to the stopper portion 15, and rotational movement is permitted until the gland 5 comes into contact with the stopper portion 15 in the rotation direction in which the gland 5 loosens.

[0050] In this example, the stem 4 is inserted into the stem hole 31, and the stopper portion 15 is positioned between the two anti-rotation portions 32 so that the inner end faces of the two anti-rotation portions 32 can each abut against the stopper portion 15 when the stem 4 rotates, while the ground engagement portion 33 holds one corner 22 or side 21 of the regular hexagonal portion (regular polygonal portion) 20 of the ground 5, and the base portion 30 is placed on the top surface of the ground 5 to attach the rotation restriction plate 10.

[0051] In this case, the corner 22 or side 21 of the regular hexagonal portion 20 to be engaged by the gland engaging portion 33 is selected so that one of the anti-rotation portions 32 (the anti-rotation portion 32 located clockwise relative to the stopper portion 15) is positioned closest to the stopper portion 15 on the side of the rotation direction (clockwise) in which the gland 5 tightens, and the rotation angle α until the other anti-rotation portion 32 contacts the stopper portion 15 in the rotation direction (counterclockwise) in which the gland 5 loosens is less than 1 / 2 of the central angle of the regular polygonal portion, i.e., less than 30°, which is 1 / 2 of the central angle θ (60°) of the regular hexagonal portion 20.

[0052] To explain the above in more detail, the gland 5 is fixed to the axle mounting tube portion 11 of the body 2 by screwing, and the rotational state of the regular hexagonal portion (regular polygonal portion) 20 after fixing (the orientation relative to the rotational direction of the regular hexagonal portion 20) changes depending on the degree to which the gland 5 is screwed in accordance with the appropriate tightening torque of the packing 7.

[0053] In contrast, the rotation restricting plate 10 is attached to the gland 5 after the gland 5 has been tightened, and therefore its orientation changes depending on the position of the gland 5 relative to the mounting tube 11 after tightening. Furthermore, since the rotation restricting plate 10 is attached using the polygonal shape of the regular hexagonal portion 20 of the gland 5, its position relative to the gland 5 is not free and changes depending on the position of the gland 5 after tightening.

[0054] The rotation restricting plate 10 is attached so as to be rotatable integrally with the gland 5 by engaging its gland engaging portion 33 with one corner 22 or side 21 of the regular hexagonal portion 20 of the gland 5. In other words, the engagement position of the gland engaging portion 33 is selected from the corner 22 or side 21 of the regular polygonal portion (regular hexagonal portion) 20 of the gland 5, so that the rotation restricting plate 10 can be attached in a rotational direction that changes in increments of half the central angle θ (60°) of the regular hexagonal portion 20.

[0055] In this embodiment, when selecting the corner 22 or side 21 of the regular polygon portion 20 when engaging the ground engaging portion 33, the rotation prevention portion 32 of the rotation restriction plate 10 is closest to the stopper portion 15 of the body 2, and the rotation angle α until it abuts against the stopper portion 15 is 30° or less, which is 1 / 2 of the central angle θ (60°) of the regular polygon portion 20 of the ground 5.

[0056] As a result, regardless of the rotational state in which the gland 5 is fastened relative to the stopper portion 15 of the body 2, after the rotation restriction plate 10 is attached, the angle at which the anti-rotation portion 32 contacts the stopper portion 15 can be made to be 30° or less, which is 1 / 2 of the central angle θ of the regular hexagonal portion 20, and since loosening of the gland 5 will only occur within that angle range, even if loosening does occur, the amount of loosening can be minimized.

[0057] As a result, when the gland 5 is screwed in, the packing 7 is tightened with an optimum torque to achieve both the axial sealing properties of the packing 7 and the torque properties during rotation of the stem 4. Regardless of the orientation of the regular hexagonal portion 20 relative to the tubular shaft portion 11, the rotation restriction plate 10 can be attached to the regular hexagonal portion 20 in a predetermined state, and the rotation of the gland 5 relative to the tubular shaft portion 11 can be restricted by the rotation restriction plate 10.

[0058] Since the regular hexagonal portion (regular polygonal portion) 20 of the gland 5 has a regular polygonal outer shape, it assumes the same shape (rotational state) each time it is rotated by the same angle as the central angle θ. Therefore, regardless of the rotational state of the gland 5 relative to the barrel portion 11 (body 2) when fastened to the barrel portion 11, according to the present invention, by appropriately selecting the corner 22 or side 21 of the regular polygonal portion 20 of the gland 5 to which the gland engaging portion 33 is fixed, the rotation restricting plate 10 can be attached to the gland 5 so that the rotation angle until the anti-rotation portion 32 contacts the stopper portion 15 is always less than ½ of the central angle θ of the regular polygonal portion 20.

[0059] The above will be specifically described with reference to the plan view of Fig. 4, which shows the rotational state of the rotation restricting plate 10 and the gland 5 after installation. Fig. 4(a) to Fig. 4(c) respectively show the state in which the rotation restricting plate 10 is installed with the gland engaging portions 33 engaged with the sides 21 of the regular hexagonal portion 20 and the stopper portion 15 positioned between the two anti-rotation portions 32, and Fig. 4(d) to Fig. 4(f) respectively show the state in which the rotation restricting plate 10 is installed with the gland engaging portions 33 engaged with the corners 22 of the regular hexagonal portion 20 and the stopper portion 15 positioned between the two anti-rotation portions 32.

[0060] (for edges) 4(a) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, any side 21 of the regular hexagonal portion 20 is positioned horizontally at the front side and the stopper portion 15 side. When the rotation restricting plate 10 shown by the two-dot chain line is attached to this gland 5, the rotation restricting plate 10 can be attached while being positioned relative to the gland 5 with two gland engaging portions (protruding pieces) 33 engaged and held at one side 21. In this case, as shown in the figure, the stopper portion 15 is positioned midway between the two anti-rotation portions 32, and this stopper portion 15 does not interfere with the attachment of the rotation restricting plate 10.

[0061] 4(b) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, the regular hexagonal portion 20 is rotated clockwise by an angle δ of approximately 15° from the state shown in FIG. 4(a). At this time, the rotation restricting plate 10 can be attached in the state shown in the figure, and the anti-rotation portion 32 on one side (left side) of the plate is closest to the stopper portion 15 in the rotation direction (clockwise) in which the gland 5 is tightened, and is in contact with the stopper portion 15. This allows the rotation restricting plate 10 to be securely attached without the stopper portion 15 interfering with the attachment of the rotation restricting plate 10, preventing further clockwise rotation of the gland 5.

[0062] 4(c) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, the regular hexagonal portion 20 rotates counterclockwise by an angle δ of approximately 15° from the state shown in FIG. 4(a). At this time, the rotation restricting plate 10 can be attached in the state shown in the figure, and the anti-rotation portion 32 on the other side (right side) of the anti-rotation portion 32 shown in FIG. 4(b) abuts against the stopper portion 15 on the side of the rotation direction (counterclockwise) that loosens the gland 5. This allows the rotation restricting plate 10 to be securely attached without the stopper portion 15 interfering with the attachment of the rotation restricting plate 10, preventing further counterclockwise rotation of the gland 5 and preventing loosening.

[0063] In the states of Figures 4(a) to 4(c) above, when attaching the rotation restricting plate 10 to the gland 5, the rotation preventing portion 32 can select the side 21 of the regular hexagonal portion 20 to be engaged by the gland engaging portion 33 so that the rotation angle α until the state of Figure 4(b) and the state of Figure 4(c) are reached is 1 / 2 the central angle θ (60°) of the regular hexagonal portion 20, i.e., 30° or less.

[0064] (In the case of corners) 4(d) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, any corner 22 of the regular hexagonal portion 20 is positioned on the near side and the stopper portion 15 side. When attaching the rotation restricting plate 10 to this gland 5, the rotation restricting plate 10 can be attached while being positioned relative to the gland 5 with the two protruding pieces 33 held between the corners 22. In this case, as shown in the figure, the stopper portion 15 is positioned midway between the two anti-rotation portions 32, and this stopper portion 15 does not interfere with the attachment of the rotation restricting plate 10.

[0065] Figure 4(e) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, the regular hexagonal portion 20 is rotated clockwise by an angle δ of approximately 15° from the state shown in Figure 4(d). At this time, the rotation restricting plate 10 can be attached in the state shown in the figure, and the anti-rotation portion 32 on one side (left side) of the plate is closest to the stopper portion 15 on the side in the rotation direction in which the gland 5 is tightened, and is in contact with the stopper portion 15. As a result, the stopper portion 15 does not interfere with the attachment of the rotation restricting plate 10, allowing the rotation restricting plate 10 to be securely attached and preventing further clockwise rotation of the gland 5.

[0066] 4(f) shows a state in which, when the gland 5 is tightened with a predetermined torque and fixed to the body 2, the regular hexagonal portion 20 rotates counterclockwise by an angle δ of approximately 15° from the state shown in FIG. 4(d). At this time, the rotation restricting plate 10 can be attached in the state shown in the figure, and the anti-rotation portion 32 on the other side (right side) of the anti-rotation portion 32 shown in FIG. 4(e) abuts against the stopper portion 15 on the side of the rotation direction (counterclockwise) that loosens the gland 5. This allows the rotation restricting plate 10 to be securely attached without the stopper portion 15 interfering with the attachment of the rotation restricting plate 10, preventing further counterclockwise rotation of the gland 5 and preventing loosening.

[0067] In the states of Figures 4(d) to 4(f) above, when attaching the rotation restricting plate 10 to the gland 5, the corner 22 of the regular hexagonal portion 20 to be engaged by the gland engaging portion 33 can be selected so that the rotation angle α of the anti-rotation portion 32 until it reaches the state of Figure 4(e) and the state of Figure 4(f) is 1 / 2 the central angle θ (60°) of the regular hexagonal portion 20, i.e., 30° or less.

[0068] As described above, the rotation restriction plate 10 can be attached by engaging the ground engaging portion (protruding piece) 33 with the side 21 of the regular hexagonal portion 20, regardless of whether the ground 5 is in the state shown in Figure 4(a), the state shown in Figure 4(b) in which it is rotated clockwise by an angle δ of 15° from the state shown in Figure 4(a), or the state shown in Figure 4(c) in which it is rotated counterclockwise by an angle δ of 15°. On the other hand, when the ground 5 is in any of the rotational states shown in FIG. 4(d), FIG. 4(e) rotated clockwise by an angle δ of 15° from the state shown in FIG. 4(d), or FIG. 4(f) rotated counterclockwise by an angle δ of 15°, the rotation restriction plate 10 can be attached by engaging the protruding pieces 33 with the corners 22 of the regular hexagonal portion 20.

[0069] When the regular polygonal portion 20 of the ground 5 is a regular hexagonal portion, the angle by which the ground 5 rotates from the state shown in Figure 4(a) to the state shown in Figure 4(d) is 30°, which is half of the central angle of the regular hexagonal portion (regular polygonal portion), 60°. In contrast to this, as described above, by engaging the protruding piece 33 with the side 21 of the regular hexagonal portion 20 in Figure 4(a), the rotation restriction plate 10 can be attached to the regular hexagonal portion 20 within a rotation range of 30°, which is the sum of the clockwise angle δ (15°) and the counterclockwise angle δ (15°) from the state in Figure 4(a).On the other hand, by engaging the protruding piece 33 with the corner 22 adjacent to the side 21 of the regular hexagonal portion 20, the rotation restriction plate 10 can be attached to the regular hexagonal portion 20 within a rotation range of 30°, which is the sum of the clockwise angle δ (15°) and the counterclockwise angle δ (15°) from the state in Figure 4(d).

[0070] In other words, since the rotation restriction plate 10 can be attached to the regular hexagonal portion 20 in a state rotated by an angle δ of 15° clockwise and counterclockwise from each of the states shown in Figures 4(a) and 4(d), the rotation restriction plate 10 can be securely attached to any of the consecutive rotation states of the regular hexagonal portion 20 from Figure 4(a) to Figure 4(d), and ultimately, the rotation restriction plate 10 can be attached in a predetermined state regardless of the rotation state in which the gland 5 is fixed relative to the body 2.

[0071] The above is also clear from the drawings. For example, the regular hexagonal portion 20 in FIG. 4(b) where the gland 5 is rotated clockwise by an angle δ of 15° from the state in FIG. 4(a) and the regular hexagonal portion 20 in FIG. 4(f) where the gland 5 is rotated counterclockwise by an angle δ of 15° from the state in FIG. 4(d) are in the same rotational state. It can be seen that the rotation restriction plate 10 can be attached by engaging the protruding piece 33 with either the side 21 or the corner 22 of these regular hexagonal portions 20.

[0072] On the other hand, the regular hexagonal portion 20 in FIG. 4(e) in which the ground 5 is rotated clockwise by an angle δ of 15° from the state in FIG. 4(d) and the regular hexagonal portion 20 in FIG. 4(c) in which the ground is rotated counterclockwise by an angle δ of 15° from the state in FIG. 4(a) are in the same rotational state, and it can be seen that the rotation restriction plate 10 can be attached by engaging the protruding piece 33 with either the side 21 or the corner 22 of these regular hexagonal portions 20.

[0073] From the above, the rotation restriction plate 10 can be attached by engaging the protruding piece 33 with the side 21 of the regular hexagonal portion 20 in the state of Figure 4(b) or the corner 22 of the regular hexagonal portion 20 in the state of Figure 4(f), or by engaging the protruding piece 33 with the corner 22 of the regular hexagonal portion 20 in the state of Figure 4(e) or the side 21 of the regular hexagonal portion 20 in the state of Figure 4(c).

[0074] Regarding these points, in the gland rotation restriction plate structure of the rotary valve of this embodiment, as described above, when attaching the rotation restriction plate 10 to the gland 5, the corners 22 or sides 21 of the regular polygonal portion 20 to be engaged by the gland engagement parts 33 are selected so that one of the rotation prevention parts 32 is positioned closest to the stopper part 15 in the rotation direction in which the gland 5 tightens, and the rotation angle α until the other rotation prevention part 32 contacts the stopper part 15 in the rotation direction in which the gland 5 loosens is an angle of 30° or less, which is 1 / 2 of the central angle θ of 60° of the regular hexagonal portion 20.Therefore, the rotation restriction plate 10 is attached with the protruding pieces 33 engaged with the sides 21 of the regular hexagonal portion 20 in the rotated state of the gland 5 in Figure 4(b) or with the protruding pieces 33 engaged with the corners 22 of the regular hexagonal portion 20 in the rotated state of the gland 5 in Figure 4(e).

[0075] In this embodiment, the angle β between the two anti-rotation portions 32 is set to ensure a rotation angle α of 30°, so that the corners 22 or sides 21 of the regular polygonal portion 20 that are engaged with the gland engaging portion 33 can be selected so that the stopper portion 15 is always positioned between these two anti-rotation portions 32. This makes it easy to attach the rotation restricting plate 10 to the gland 5 at a position that minimizes loosening of the gland 5.

[0076] The gland rotation restriction plate structure of the rotary valve of the present invention uses the rotation restriction plate 10 of the above-mentioned shape, so that the rotation restriction plate 10 can be easily attached to an existing ball valve 1 to restrict the rotation of the gland 5 without performing any processing on the ball valve 1.

[0077] When the rotation restriction plate 10 is attached to the body 2 (axial tube portion 11), its ground engagement portion 33 is engaged with the corner 22 or side 21 of the regular hexagonal portion 20, and the stopper portion 15 of the axial tube portion 11 is positioned between the two anti-rotation portions 32. Then, by screwing the nut 43 into the stem 4 via the handle 6 and washer 44, the rotation restriction plate 10 can be fixed integrally with the ground 5 in a rotatable state relative to the axial tube portion 11.

[0078] Since the rotation restricting plate 10 is not fixed to the axle mounting tube portion 11 (body 2), even if the processing precision of the body 2 is low and there is an error in the dimensional precision of the stopper portion 15, the rotation restricting plate 10 can be attached without generating any play between it and the gland 5.

[0079] The rotation restricting plate 10 can restrict rotation of itself and the gland 5 relative to the body 2 by contacting the anti-rotation portion 32 with the stopper portion 15, and can prevent excessive loosening of the gland 5 and the stem 4 from coming off even when the stem 4 is repeatedly rotated. Furthermore, if the diameter (inner diameter) φdh of the stem hole 31 in the rotation restricting plate 10 is formed small so that the gap between the stem 4 and the stem hole 31 is smaller, the play that occurs between the rotation restricting plate 10 and the stem 4 is further reduced, and the rotation restricting plate 10 can be attached with high precision.

[0080] When the rotation restricting plate 10 is attached to the gland 5 in a state in which the packing 7 has been tightened with the appropriate torque, the rotation restricting plate 10 can be attached without adjusting the orientation of the regular hexagonal portion 20, i.e., the degree to which the gland 5 is screwed in. In this way, regardless of the orientation of the gland 5, i.e., regardless of the rotation state of the regular hexagonal portion 20, the rotation restricting plate 10 can be securely attached to the regular hexagonal portion 20. Therefore, the gland 5 can be tightened and fixed to the body 2 while prioritizing the appropriate torque of the packing 7, and the functionality of the packing 7, such as the shaft sealing performance and operability of the stem 4, can be most effectively exhibited, and the gland 5 is less likely to loosen.

[0081] If the gland 5 were to rotate in a loosening direction for some reason, the anti-rotation portion 32 of the rotation restriction plate 10 attached integrally to the gland 5 would come into contact with the stopper portion 15, preventing further rotation of the gland 5. In this case, the rotation angle α until the anti-rotation portion 32 comes into contact with the stopper portion 15 is set to a relatively small angle of 30° or less, which is half the central angle θ of the regular hexagonal portion 20, thereby minimizing loosening of the gland 5. This reliably prevents problems such as the gland 5 falling off, while maintaining sufficient pressure on the packing 7 by the gland 5 and maintaining its sealing performance.

[0082] Furthermore, when the gland 5 is used to retighten the packing 7 that has deteriorated over time due to long-term use of the ball valve 1, the rotation restriction plate 10 can be reattached to the gland 5 in the specified state regardless of how the rotational state of the regular hexagonal portion 20 of the gland 5 changes after retightening, which is advantageous for performing appropriate retightening as needed.

[0083] The above describes in detail the embodiments of the present invention, but the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the spirit of the invention described in the claims of the present invention.

[0084] For example, in the above-described embodiment, the portion of the gland 5 exposed at the top of the axle tube 11 of the body 2 is a regular polygonal portion (regular hexagonal portion) 20, and the gland locking portion 33 of the rotation restricting plate 10 is locked to the corners 22 or sides 21 of this regular polygonal portion 20. However, the manner in which the rotation restricting plate 10 is locked to the gland 5 is not limited to this. For example, the portion corresponding to the regular polygonal portion 20 may not be polygonal, but may have a shape like two parallel faces or a circle with only one side cut out, and the gland 5 may be provided with gland locking portions shaped to be locked to these sides, and these sides and the gland locking portions may be locked together, or the rotation restricting plate 10 and the gland 5 may be locked together by partially crimping them together.

[0085] Even in these configurations, if the rotation restriction plate 10 is engaged with the gland 5 by the gland engaging portion so that the anti-rotation portion 32 is not fixed in position in the rotation direction relative to the stopper portion 15 and is allowed to rotate until it comes into contact with the stopper portion 15 in the rotation direction in which the gland 5 loosens, it is possible to tighten and fix the gland 5 to the body with an optimal torque while attaching the rotation restriction plate 10 to the gland 5 to achieve the effect of suppressing loosening of the gland 5. [Explanation of symbols]

[0086] 1. Ball valve (rotary valve) 2 Body 3 balls 3a through hole 4 Stem 5 grand 6 Handle 10 Rotation control plate 11 Shaft tube part 13 Top opening 15 Stopper part 20 Regular hexagonal part (regular polygonal part) 21 sides 22 angles 30 Base 31 Stem hole 32 Anti-rotation part 33 Projecting piece (ground engaging part) α rotation angle θ central angle φdh Inner diameter of stem hole φDs Outer diameter of stem

Claims

1. A rotary valve gland rotation restriction plate structure comprising a gland screwed into an upper opening of a tubular shaft formed in the body of the rotary valve, and a rotation restriction plate attached to the gland to restrict its rotation, wherein the body has a stopper portion that restricts the rotational range of a handle that rotates the stem, and the rotation restriction plate has at least a base portion that is placed on the gland, a stem hole that passes through the center of the base portion, a rotation prevention portion that protrudes radially from the base portion and can abut against the stopper portion, and a gland engagement portion that engages the rotation restriction plate with the gland so that it can rotate together with the gland, and wherein when the rotation restriction plate is attached to the gland, the rotation prevention portion is not fixed in position relative to the stopper portion in the rotational direction, and the gland engagement portion is engaged with the gland so that it is allowed to rotate in the rotational direction in which the gland loosens until it comes into contact with the stopper portion.

2. The rotary valve has a structure in which a gland is screwed into an upper opening of a cylindrical portion formed in the body of the rotary valve, and a rotation restriction plate is attached to the gland to restrict its rotation, the gland having a regular polygonal portion at a portion exposed at the upper part of the body, the body having a stopper portion that restricts the rotation range of a handle that rotates the stem, and the rotation restriction plate has at least a base portion placed on the gland, a stem hole that is passed through the center of the base portion, a rotation stopper portion that protrudes from the base portion in the outer circumferential direction and can abut against the stopper portion, and a rotation restriction plate that protrudes from the base portion in the outer circumferential direction. a gland engagement portion that engages with the gland to hold one corner or side of the regular polygonal portion of the gland, and a gland engagement portion that engages with the gland engagement portion to hold one corner or side of the regular polygonal portion of the gland, wherein when the rotation limiting plate is attached to the gland, the rotation limiting portion is positioned closest to the stopper portion on the side of the rotation direction in which the gland tightens relative to the stopper portion, and the corner or side of the regular polygonal portion to be engaged with the gland engagement portion is selected so that the rotation angle until the rotation limiting portion contacts the stopper portion in the rotation direction in which the gland loosens is less than 1 / 2 of the central angle of the regular polygonal portion.

3. The rotation restricting plate has two anti-rotation portions, and is positioned so that the angle at which rotation is possible from when one anti-rotation portion abuts the stopper portion until the other anti-rotation portion abuts the stopper portion is less than 1 / 2 of the central angle of the regular polygonal portion.

4. 4. A rotary valve gland rotation restricting plate structure as described in claim 2 or 3, wherein the gland engaging portion is formed by two protruding pieces that protrude radially from the base portion approximately parallel to each other and hang down toward the gland, and these protruding pieces hold the corners of the regular polygonal portion or engage one side of it to hold it in place.

5. 3. The gland rotation restricting plate structure for a rotary valve according to claim 1, wherein the stem hole has a diameter slightly larger than that of the stem.

6. The rotary valve according to claim 1 or 2 is a ball valve having a ball with a through hole rotatably arranged within the body, the stem that rotates the ball is arranged in the axially mounted cylindrical portion, and the upper part of the stem is rotated by the handle.

Images