JP2019177936A - Attachment structure for manhole cover of pressure tank and particulate matter transport vehicle - Google Patents

Abstract

To avoid an abrupt upward movement of a manhole cover of a pressure tank due to tank internal pressure and thus prevent the cover and a tank body from being broken owing to an impact in a process of unlocking lock means for the manhole cover of the pressure tank.SOLUTION: An attachment structure for a manhole cover of a pressure tank comprises: fastening means P which fastens a cover C to a manhole H: lock means L for the cover which is provided separately from the fastening means; and an interlocking mechanism I which allows the fastening means P and lock means L to interlock. The fastening means P comprises: a push member 6 which can be operated to move between a fastening completion position 6A and an unfastening completion position 6B; and a cover press member 7 which makes fastening force act on the cover C on receiving press force from the push member 6. The interlocking mechanism I makes, when the push member 6 is present between a fastening start position 6X1 where it at least starts applying press force to the cover press member 7 and the fastening completion position 6A, the push member 6 and lock means L interlock so that the push member 6 holds the lock means L in a lock posture.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a mounting structure for a manhole cover in a pressure tank comprising a tank body capable of pressurizing the inside, a manhole provided in the tank body, and a cover attached to the tank body so that the manhole can be opened and closed, and The present invention relates to a granular material transport vehicle having a manhole cover mounting structure.

  Such a granular material transport vehicle is already known as disclosed in Patent Document 1 below, and in this case, in order to promote the discharge of the granular material from the press-fit tank, the inside of the tank body is pressurized. It is possible. Further, between the cover and the tank body, there is provided a tightening holding means capable of tightening and holding the cover against the tank internal pressure at the manhole closing position.

Japanese Utility Model Publication No. 56-175390

  In the press-fitting tank of Patent Document 1, a fastening tool 18 provided at the center of the cover 4 so as to be movable up and down and a hook 17 fixed to the tank body 1 are always connected to each other so as to constitute the fastening holding means. A series of links in a connected state, that is, a fastening arm 13 and an arm rod 15 are interposed, and the arm rod 15 and the cover 4 are connected by a connecting rod 16.

  When the fastening tool 18 is lowered to the fastening position, the arm rod 15 is closely engaged with the hook 17 via the fastening arm 13, so that the cover 4 at the manhole closing position is sandwiched between the packing 22 and the manhole. The cover 4 is locked to the tank body 1 while being tightened to the opening end.

  Also, when the clamp 18 is lifted to the tightening release completion position from that state, the arm rod 15 interlocking with the tightening arm 13 is completely detached from the hook 17 through a half-hanging state. The cover 4 is released in the state.

  However, when pressurized air remains in the tank in the half-hanging state and the cover 4 is forcibly moved upward by the pressurized air, the cover 4 cannot be stopped by the half-hanging armband 15. As a result, the cover 4 may move up suddenly, and the cover or the tank body may be partially damaged by the impact at that time.

  The present invention has been proposed in view of the above, and an object thereof is to provide a manhole cover mounting structure and a granular material transport vehicle that can solve the problems of the conventional structure with a simple structure.

  In order to achieve the above object, the present invention provides a pressure tank comprising a tank body capable of pressurizing the inside, a manhole provided in the tank body, and a cover attached to the tank body so that the manhole can be opened and closed. In the manhole cover mounting structure according to claim 1, a fastening means capable of applying a fastening force for fastening the cover to the opening end of the manhole, a cover locking means provided separately from the fastening means, and the fastening And an interlocking mechanism for interlocking the locking means, wherein the locking means is between a locking posture for locking the cover with respect to the tank body at a manhole closed position and an unlocking posture for releasing the locking. And the tightening means can be arbitrarily moved between a tightening completion position and a tightening release completion position. And a cover holding member that applies the tightening force to the cover in response to receiving a pressing force from the push member, and the interlock mechanism is configured such that the push member pushes at least the cover holding member. When the pressure member is between the tightening start position where pressure is applied and the tightening completion position, the push member and the lock means are interlocked and connected so that the push member holds the lock means in the locked posture. This is the first feature.

  Further, according to the present invention, in addition to the first feature, the interlock mechanism includes a lock holding limit position where the push member is displaced by a predetermined amount from the tightening start position to the tightening release completion position and the tightening completion. The locking member is held in the locked position by the push member when the push member is in the position, but when the push member is closer to the tightening release completion position than the lock holding limit position, the push member is A second feature is that the push member and the locking means are interlocked and connected so as to allow the posture change of the locking means from the locked posture to the unlocked posture.

  According to the present invention, in addition to the second feature, the push member can be moved up and down between the tightening completion position and the tightening release completion position. The cover holding member is arranged so as to extend radially from the center of the cover and is pivotally supported by the cover or the tank main body so as to be swingable. It is composed of a plurality of holding arms that can convert the pressing force received from the push ring into a tightening force to the cover, and the push ring can be engaged with and disengaged from the radially inner ends of the plurality of holding arms. When the push ring is in the tightening release completion position with respect to the tightening start position, the push ring is separated from the restraining arm, and when the push ring is in the tightening completion position, the suppression is performed. The arm is engaged so as to apply the pressing force, and when the push ring reaches the tightening start position while moving from the tightening release completion position toward the tightening completion position, A third feature is that the push ring starts engaging with the holding arm and starts applying a pressing force to the cover holding member.

  According to the present invention, in addition to the third feature, the lock means includes a fixed lock member fixed to one of the cover and the tank body, and a lock position and an unlock position provided on either one of the two. A movable lock member movable between the movable lock member and the movable lock member to lock the cover in the manhole closed position by engaging with the fixed lock member in the locked position, and in the unlocked position. The interlocking mechanism is configured to release the locking, and the interlocking mechanism has an interlocking arm that is supported on the cover so as to be movable between a predetermined radially inner position and a radially outer position. The interlocking arm is in the radially outward position when the movable locking member is in the locked position, and is in the radially inward position when the movable locking member is in the unlocked position. As described above, the movable lock member is interlocked and connected, and the radially inner end portion of the interlocking arm and the outer peripheral portion of the push ring are configured to be detachable from each other. When it is between the lock holding limit position and the tightening completion position, the interlocking arm is held at the radially outward position by the push ring, but the push ring is more than the lock holding limit position. When in the tightening release completion position side, the interlock arm is released from the push ring, and the interlock arm is allowed to move from the radially outward position to the radially inward position. 4 features.

  Further, according to the present invention, in addition to the fourth feature, the interlocking arm includes a radially inner arm portion that is slidably contacted on the cover, and the movable arm is movable from the radially inner arm portion. A radially outer arm portion extending toward the lock member, and the radially outer arm portion can be used as a handle portion that projects upward from the radially inner arm portion. It is the fourth feature.

  Moreover, this invention is a granular material transport vehicle provided with the attachment structure of the cover for manholes in the pressure tank which has the characteristics in any one of the 1st-5th, Comprising: The said pressure tank which can accommodate a granular material inside Is mounted on the vehicle body as a sixth feature.

  According to the first aspect of the present invention, when the push member of the tightening means is operated from the tightening completion position to the tightening release direction, the push member reaches at least the tightening start position, that is, push. The push member reliably holds the locking means in the locked position via the interlocking mechanism until the clamping force applied from the member to the cover via the cover holding member is lost and the residual pressure in the pressure tank is sufficiently reduced. Can be held. As a result, it is possible to reliably prevent a situation where the cover suddenly rises due to the residual pressure in the pressure tank when the locking means is half-hanged. Can be effectively avoided.

  In particular, according to the second feature, when the push mechanism is between the lock holding limit position where the push member is deviated by a predetermined amount from the tightening start position to the tightening release completion position and the tightening completion position, The push member holds the locking means in the locked position, but when the push member is closer to the tightening release completion position than the lock holding limit position, the push member is allowed to change the posture of the locking means from the locked position to the unlocked position. In this manner, the push member and the locking means are interlocked and connected. Thus, when the push member is operated in the tightening release direction from the tightening completion position, the pressure tank reaches the lock holding limit position that is further biased to the tightening release completion position side than the tightening start position. Since the push member can reliably hold the locking means in the locked posture via the interlocking mechanism until the residual pressure in the inside is more reliably released, the above-described effect of the first feature can be achieved more reliably. Safety is further improved.

  In particular, according to the third feature, even if the fastening means is interlocked and connected to the locking means via the interlocking mechanism, the same amount of the plurality of restraining arms can be simultaneously applied by one common push ring of the fastening means. Since the tightening operation or the tightening release operation can be performed one by one, it is possible to simplify the structure of the tightening means and thus contribute to cost reduction.

  In particular, according to the fourth feature, when the push ring is between the lock holding limit position and the tightening completion position, the interlocking arm is held in the radially outward position by the push ring. When it is on the tightening release completion position side from the lock holding limit position, the interlocking arm is released from the push ring, and the movement of the interlocking arm from the radially outer position to the radially inner position is allowed. The displacement in the radial direction of the interlocking arm connected to the locking means can be accurately regulated / deregulated with the push ring. As a result, the push ring, which is the main component of the tightening means, can be linked and connected to each other with a simple interlocking structure in which the movable lock member is linked to the movable locking member via the interlocking arm. Can contribute to cost savings.

  In particular, according to the fifth feature, the interlocking arm of the interlocking arm is slidably abutted on the cover, and from the radially inward arm part toward the movable lock member. Since the extending radially outer arm part can be used as a handle protruding upward from the radially inner arm part, the radially inner arm part and the outer part of the single arm (interlocking arm) The side arm portion can be selectively used as a sliding means on the cover and a grip means, so that the handling operation is simple and further simplification of the structure can be achieved.

  In particular, according to the sixth feature, in the granular material transport vehicle, the tightening release operation of the manhole cover can be performed more safely and accurately even if pressurized air remains in the pressure tank.

The whole side view which shows one Embodiment of the granular material transport vehicle which concerns on this invention Enlarged plan view showing the manhole cover of the granular material transport vehicle and its peripheral part (enlarged view taken in the direction of arrow 2 in FIG. 1) 2 is a cross-sectional view taken along line 3-3 in FIG. 2 in a state where the push ring is in the tightening completion position. 2 is a cross-sectional view taken along line 4-4 in FIG. 2 in a state where the push ring is in the tightening completion position. FIG. 4 correspondence diagram showing a state where the push ring is in the tightening start position FIG. 4 correspondence diagram showing a state where the push ring is at the lock holding limit position FIG. 4 is a view corresponding to FIG. 4 showing a state in which the push ring is closer to the tightening release completion position than the lock holding limit position and the locking means is unlocked.

  Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

  First, in FIG. 1 to FIG. 6, a pressure tank T capable of accommodating a granular material (for example, cement, feed, fertilizer, etc.) is mounted on the vehicle body F of the granular material transport vehicle V.

  The pressure tank T is formed in a substantially cylindrical shape and extends in the front-rear direction, a hollow tank body Tm, a plurality of manholes H that are opened at the front and back of the tank body Tm, and the manholes H are opened and closed. A cover C for opening and closing, a hatch 11 for opening and closing a discharge port provided at a lower rear end of the tank body Tm, and a discharge pipe 12 connected to the hatch 11 and communicating with the inside of the tank body Tm. The discharge pipe 12 is provided with an open / close valve (not shown) that can be arbitrarily opened and closed.

  The rear end of the tank body Tm is pivotally supported by the rear portion of the vehicle body F, and can swing so as to tilt or dump backward around the pivotal support. A hydraulically operated lift cylinder A as an actuator is interposed between the front part of the tank body Tm and the vehicle body F, and the tank body Tm is forced rearward by the extension of the lift cylinder A. Can be tilted (see the dashed lines and white arrows in FIG. 1). The manhole H is a circular hole for maintenance and introduction of the granular material into the pressure tank T. In this embodiment, the manhole H is a short cylindrical shape which is airtightly penetrated and coupled (for example, welded) to the upper wall of the tank body Tm. It is formed by the inner peripheral part of the manhole forming cylinder 1. The manhole forming cylinder 1 may be integrally formed (for example, press-molded) on the tank main body Tm instead of being connected to the tank main body Tm later as in the present embodiment.

  On the other hand, the manhole cover C is formed in a substantially disk shape slightly larger than the manhole H. A downward annular groove 13 is formed on the outer peripheral portion of the bottom surface of the cover C, and an annular packing 14 made of an elastic material (for example, a rubber material) is fitted into the annular groove 13. The packing 14 is disposed at a position where it can be pressed against the opening end of the manhole H (that is, the open upper end 1 e of the manhole forming cylinder 1).

  Therefore, when the cover C is tightened downward with respect to the opening end of the manhole H by the tightening means P described later, a part of the packing 14 is compressed and deformed by the tightening force, and the opening end of the manhole H and the cover are covered. It can block | close, sealing airtightly between C outer periphery parts.

  A compressor C which is a supply source of pressurized air to be supplied into the tank main body Tm and the discharge pipe 12 is mounted at an appropriate position of the vehicle body F. The air pipe La and the ejector pipe Le branched from the compressor pipe Lc extending from the compressor C and extending rearward are communicated with each other in the tank main body Tm and the latter in the discharge pipe 12.

  The cover C is attached to the upper part of the tank body Tm so that the manhole H can be opened and closed. Next, the mounting structure will be described with reference to FIGS.

  Around the manhole H, a vertical support column 19 is fixed upright (for example, welded) to the upper portion of the tank body Tm, and the base link 20 is rotatably fitted and held on the support column 19 via a bearing. The The base link 20 is pivotally connected to the base ends of the first and second intermediate links 21 and 22 extending in parallel with each other, and the front link 23 is connected to the distal ends of the intermediate links 21 and 22. The base is pivotally connected to be pivotable. The outer periphery of the cover C is fixed (for example, welded) to the tip of the tip link 23.

  The base link 20, the first and second intermediate links 21, 22 and the front link 23 constitute a parallel link mechanism LL in cooperation with each other. Therefore, as the parallel link mechanism LL swings up and down, the cover C moves up and down (see the chain line in FIG. 3) while maintaining a horizontal posture and with a slight horizontal displacement with respect to the opening end of the manhole H. . An elastic member 24 (for example, a torsion coil spring) for assisting the upward displacement of the cover C is interposed between the intermediate links 21 and 22 and the base link 20.

  Further, by rotating the base link 20 around the support column 19 with the cover C slightly lifted from the opening end of the manhole H, the parallel link mechanism LL (and thus the cover C) is pivotally displaced about the vertical axis. The cover C closes the opening end of the manhole H, that is, the opening end of the manhole H and the opening end of the manhole H sufficiently away from the opening upper end 1e of the manhole forming cylinder 1 by the above-described vertical displacement and turning displacement. It can move between manhole closing positions (for example, the solid line positions in FIGS. 1 to 6).

  Furthermore, the cover C mounting structure of the tank body Tm of the present embodiment includes a tightening means P capable of applying a tightening force for tightening the cover C with the packing 14 sandwiched between the opening end 1e of the manhole H, and a tightening means P. The locking means L for locking the closed position of the cover C and the interlocking mechanism I for interlocking the fastening means P and the locking means L are provided separately. Next, the means P, L, and I will be described.

  The lock means L can change its posture between a locked posture that prevents the cover C from being detached from the manhole closing position and an unlocked posture that releases the lock by locking the cover C to the tank body Tm.

  The lock means L includes a fixed lock member 10 fixed to the tank body Tm, and a movable lock member 9 provided on the cover C and movable between a lock position 9A and an unlock position 9B. In the present embodiment, the fixed lock member 10 has a U-shaped fixed bracket 10b standing upright on the tank body Tm, and a lock pin 10p horizontally connected to the fixed bracket 10b. The movable lock member 9 is formed of a hook member that is swingably supported via a pivot 16 between a pair of support plates 15 fixed on the upper surface of the outer peripheral portion of the cover C and that can be engaged with and disengaged from the lock pin 10p. .

  When the movable lock member 9 is in the lock position 9A (see FIGS. 4 to 6), that is, when the lock means L is in the lock position, the movable lock member 9 is locked to the lock pin 10p to lock the cover C in the manhole closed position. Is possible. When the movable lock member 9 is in the unlock position 9B (see FIG. 7), that is, when the lock means L is in the unlock position, the lock on the lock pin 10p is released to close the manhole of the cover C. The cover C can be opened / closed by allowing the detachment from the position.

  In the present embodiment, an urging member 17 (for example, twisted) that constantly urges and urges the movable lock member 9 toward the lock position 9A between the movable lock member 9 and the support plate 15 (cover C). Coil springs) and swing stopper means 18 capable of holding the movable lock member 9 at the lock position 9A against the urging force of the urging member 17 are provided. The swing stopper means 18 includes, for example, a pin 15p fixed to the support plate 15 and an arm portion 9s fixed to the movable lock member 9 and detachable from the pin 15p.

  In this embodiment, a slight gap is set between the movable lock member 9 and the lock pin 10p while the movable lock member 9 is held at the lock position 9A. However, this gap is omitted. May be.

  Next, the fastening means P will be described. The tightening means P is tightened to the cover C according to the push member 6 that can be arbitrarily moved between the tightening completion position 6A and the tightening release completion position 6B and receiving a pressing force from the push member 6. And a cover holding member 7 for applying a force.

  Here, the tightening completion position 6A means that when the push member 6 is tightened (that is, moved downward) to this position, a sufficient tightening force can be applied to the cover C to ensure the airtightness of the pressure tank T. Says the position.

  Further, the tightening release completion position 6B refers to the opening end portion of the cover C and the manhole H (the open upper end portion of the manhole forming cylinder 1) when the push member 6 is returned to this position in the tightening release direction (that is, moved upward). 1e) refers to a position where the air leakage from the position 1e is surely eliminated and the unlocking operation of the locking means L with respect to the cover C is reliably permitted. The tightening release completion position 6B may be coincident with the ascent limit position of the push ring 6, or a position slightly below the ascent limit position (however, a predetermined amount above the lock holding limit position 6X2 described later). (Position on the side) may be the tightening release completion position 6B.

  The push member is composed of a single push ring 6 provided at the center of the cover C so that it can be moved up and down between at least a tightening completion position 6A and a tightening release completion position 6B. That is, a vertical screw shaft 32 is screwed onto the inner peripheral surface of the support cylinder 31 fixed to the center portion of the cover C, and the upper portion of the push ring 6 is connected to the upper portion of the screw shaft 32 via the bearing 33. A holding ring 34 that is rotatably supported is pivotally connected via a connecting pin 36.

  Further, a base portion of an operation lever 35 for rotating the screw shaft 32 is pivotally connected to the upper portion of the screw shaft 32. A stopper projection 35a is provided on the lower surface of the base portion of the operation lever 35 so as to come into contact with and separate from the upper surface of the push ring 6. The stopper projection 35a defines the downward swing limit of the operation lever 35. The open lower end of the support cylinder 31 facing the tank body Tm is closed by a cap 50 that is detachably fitted to the support cylinder 31.

  The operation lever 35 can be raised and lowered at any time around the connecting pin 36. The operator can adjust the screwing position of the screw shaft 32 with respect to the support tube 31 by grasping the tip of the operation lever 35 and rotating the holding ring 34 and the screw shaft 32 around the center axis of the cover C. By adjusting the screwing position, the lift position of the push ring 6 with respect to the cover C can be arbitrarily adjusted.

  On the other hand, the cover holding member 7 is composed of a plurality of holding arms 7 arranged so as to extend radially from the center of the cover C, and each holding arm 7 has a radially outer end portion of the tank body Tm (more than Specifically, it is pivotally supported 37p on a bracket 37) fixed to the manhole forming cylinder 1 so as to be swingable up and down. Each holding arm 7 has a belt-like arm main body 7m and a vertical rib 7r that protrudes integrally at the center in the width direction of the upper surface of the arm main body 7m and extends in the longitudinal direction of the holding arm 7. Here, in this application, the radial direction refers to the radial direction of the cover C, the radially inner side is the center side of the cover C (screw shaft 32 side), and the radially outer side is the outer peripheral side of the cover C (annular groove 13 side). ).

  On the lower surface of the arm body 7m, a pressing projection 7ma is provided so as to be in contact with and disengageable from the outer peripheral portion of the upper surface of the cover C at a position near the shaft support 37p. When a downward tightening force is applied from the push ring 6 to each restraining arm 7 as will be described later, the restraining arm 7 receives the pressing force received from the push ring 6 by swinging around its pivotal support 37p. Can be converted into a tightening force to the cover C.

  The push ring 6 has a pair of engagements that project radially outward from the outer periphery of the ring body 6m corresponding to the disk-shaped ring body 6m and the radially inner ends of the plurality of holding arms 7. And a convex portion 6t. Each pair of engaging projections 6t sandwiches the radially inner end of the vertical rib 7r of the corresponding holding arm 7 in the circumferential direction of the cover C, and can prevent the push ring 6 from rotating. The lower surface of each engaging projection 6t is engaged with and supported by the upper surface of the arm body 7m on both sides of the vertical rib 7r of each holding arm 7 so as to be able to contact and separate.

  On the upper surface of the cover C, a pair of stopper pins 38 are integrally provided so as to sandwich a pair of engaging projections 6t corresponding to at least some of the holding arms 7 from both sides in the circumferential direction of the cover C. Both the stopper pins 38 function as a detent means for the push ring 6 at all times (thus, even when the push ring 6 is separated from the restraining arm 7 and raised to the tightening release completion position 6B). Thereby, when the operation lever 35 is rotated, it is possible to reliably prevent the push ring 6 from rotating around the holding ring 34 that rotates following the operation lever 35.

  The push ring 6 is configured so as to be able to be engaged with and disengaged from the radial inner ends 7i of the plurality of holding arms 7, and is separated from the holding arms 7 when the push ring 6 is displaced upward by a predetermined amount or more in the tightening release direction. When the push ring 6 is in the lower limit position, that is, the tightening completion position 6A, the pressing arm 7 is engaged so as to apply a sufficient pressing force. Further, when the push ring 6 reaches the tightening start position 6X1 while moving downward from the tightening release completion position 6B toward the tightening completion position 6A, the push ring 6 starts engaging with the restraining arm 7 (more specifically, Specifically, the lower surface of the engaging convex portion 6t starts to come into contact with the upper surface of the arm body 7m) and starts to apply a pressing force to the cover holding member 7.

  Next, the interlocking mechanism I will be described. The interlocking mechanism I locks the locking means L with the push member 6 when the push member 6 is between the tightening start position 6X1 and the tightening completion position 6A where the push member 6 starts to apply pressure to at least the cover holding member 7. The push member 6 and the lock means L are interlocked and connected so as to be held at the same position.

In particular, in this embodiment, the interlocking mechanism I is located between the lock holding limit position 6X2 and the tightening completion position 6A where the push member 6 is displaced by a predetermined amount from the tightening start position 6X1 to the tightening release completion position 6B. At this time, the lock member L is held in the locked posture by the push member 6. However, when the push member 6 is closer to the tightening release completion position 6B than the lock holding limit position 6X2, the push member 6 is moved from the locked posture of the lock member L. The push member 6 and the locking means L are interlocked and connected so as to allow the posture change to the unlocked posture (that is, unlocking operation). That is, the interlocking mechanism I is located on the cover C in a predetermined radial inner position. The interlocking arm 8 is supported so as to be slidable in the radial direction between 8B and the radially outward position A, and an inverted U-shaped guide member 39 that guides the sliding of the interlocking arm 8. The outer end 8o in the radial direction of the interlocking arm 8 is pivotally supported and connected to the base of the movable lock member 9 via the pivot 51, whereby the interlocking arm 8 has the movable lock member 9 in the locked position 9A. When the movable lock member 9 is in the radially outward position 8A, and when the movable lock member 9 is in the unlocked position 9B, the movable lock member 9 is linked to and connected to the radially inward position 8B.

  The interlocking arm 8 is disposed so as to face the outer peripheral portion of the ring main body 6m of the push ring 6 through a small gap when the interlocking arm 8 is at the radially outer position 8A, and a radially inner end portion 8i extending in the vertical direction, A radially inner arm portion 8b that extends substantially horizontally to the lower end portion of the radially inner end portion 8i and slidably contacts the cover C in a radially slidable manner, and is movable from the radially inner arm portion 8b. And a radially outer arm portion 8c extending toward the lock member 10. The radially outer arm portion 8c projects upward from the radially inner arm portion 8b, and can also be used as a handle portion that can be easily gripped by the operator.

  The radially inner end portion 8 i of the interlocking arm 8 and the outer peripheral portion of the push ring 6 can be engaged and disengaged with each other according to the vertical displacement of the push ring 6. More specifically, when the push ring 6 is between the lock holding limit position 6X2 and the tightening completion position 6A (see FIGS. 4 to 6), the radially inner end of the interlocking arm 8 is used. Since the portion 8i is in a position close to and opposed to the outer periphery of the ring main body 6m of the push ring 6, the movement of the interlocking arm 8 toward the radially inward side is restricted by the engagement of the push ring 6 and the interlocking arm 8. That is, the interlocking arm 8 is held at the radially outward position 8A.

  On the other hand, the push ring 6 cannot be engaged with the interlocking arm 8 when it is displaced upward from the lock holding limit position 6X2 to the tightening release completion position 6B (see FIG. 7). Movement of the arm 8 from the radially outer position 8A to the radially inner position 8B is not restricted by the push ring 6. Accordingly, in this state, the operator can grasp the interlocking arm 8 (for example, the radially outward arm portion 8c) and move to the radially inward position 8B, and lock the movable lock member 9 in accordance with the moving operation. The position 9A can be displaced to the unlock position 9B (FIG. 7).

  Next, the operation of the embodiment will be described. The cover C that closes the manhole H above the pressure tank T normally receives a sufficient tightening force from the push ring 6 at the tightening completion position 6A (FIG. 4) via the restraining arm 7, so the cover C and the manhole The gap between the open ends of H is securely sealed in an airtight manner with the packing 14 interposed therebetween.

  In this state, since the radially inner end 8i of the interlocking arm 8 is close to and opposed to the outer periphery of the push ring 6, the interlocking arm 8 connected to the movable lock member 9 is on the radially inner side thereof. Movement (and hence displacement of the movable lock member 9 to the unlock position 9B) is restricted by the push ring 6, and the unlocking operation of the lock means L is restricted. As a result, the cover C is securely held at the manhole closing position, and there is no risk of inadvertent opening.

  And when the granular material transport vehicle V which accommodated the granular material in the pressure tank T arrives at the destination and discharges the granular material from the inside of the pressure tank T, for example in the downstream end part of the discharge pipe 12 The upstream end of the discharge hose 41 (delivery hose) is connected, and the downstream end of the discharge hose 41 is connected to a granular material container 42 (for example, a silo).

  Next, the on-off valve in the discharge pipe 12 is opened and the compressor C is operated. As a result, the pressurized air flowing into the pressure tank T from the compressor pipe Lc through the air pipe La is jetted into the tank body Tm through a canvas (not shown) stretched over a wide area at the bottom of the tank body Tm. Therefore, the blown air pressurizes the inside of the pressure tank T and promotes fluidization of the powder on the canvas. As a result, in the pressure tank T, the slide flow to the rear of the granular material is assisted and promoted, and the granular material can be efficiently discharged to the discharge pipe 12 side. On the other hand, the pressurized air ejected from the compressor pipe Lc through the ejector pipe Le into the discharge pipe 12 can further assist and promote the discharge of the granular material from the discharge pipe 12.

  In the above-described granular material discharging step, the pressure tank T is tilted backward by the lift cylinder A as necessary. Thereby, the backward flow of the granular material in the pressure tank T and the granular material discharge from the discharge pipe 12 are further promoted.

  By the way, at the time of maintenance work in the pressure tank T or charging of the granular material, for example, it is necessary to open the cover C to open the manhole H.

  In this case, normally, after opening the air release valve (not shown) communicating with the pressure tank T and the atmosphere to depressurize the pressure tank T, the tightening completion position 6A (FIG. 4) is used to close the cover C. The push ring 6 placed on the reference) is gradually moved up and displaced by the turning operation of the operation lever 35 in the loosening direction. Along with this upward displacement, the pressing force acting on the restraining arm 7 from the push ring 6 gradually decreases, and accordingly, the tightening force (and hence the sealing force of the packing 14) applied to the cover C by the restraining arm 7 gradually. descend. Therefore, even if high-pressure pressurized air remains in the pressure tank T before work, the pressurized air gradually leaks from the gap between the opening end of the cover C and the manhole H, and the pressure tank T The internal pressure gradually decreases.

  When the push ring 6 reaches the tightening start position 6X1 shown in FIG. 5, the tightening force acting on the cover C from the push ring 6 via the restraining arm 7 is substantially eliminated. At this time, since only the weight of the cover C and the holding arm 7 acts on the packing 14, the packing 14 causes the cover C to move from its state shown in FIG. 4 by its own elastic restoring force as clearly shown in the partial enlarged view of FIG. Also raise a little. Even in this state, since the radially inner end 8i of the interlocking arm 8 is in close proximity to the outer peripheral portion of the push ring 6, the interlocking arm 8 connected to the movable lock member 9 is radially inward. Movement to the side (and hence displacement of the movable lock member 9 to the unlock position 9B) is restricted by the push ring 6, and the movable lock member 9 is securely held at the lock position 9A.

  Next, the push ring 6 is further displaced upward so that when the push ring 6 reaches the lock holding limit position 6X2 shown in FIG. 6, the relationship between the outer peripheral portion of the push ring 6 and the radially inner end portion 8i of the interlocking arm 8 is established. Even in this state, the movement of the interlocking arm 8 inward in the radial direction (and hence the displacement of the movable lock member 9 to the unlock position 9B) is still restricted by the push ring 6 (that is, the movable lock). The member 9 is held at the lock position 9A).

  However, if the push ring 6 is moved upwardly and further to the tightening release completion position 6B side than the lock holding limit position 6X2 as shown in FIG. 7, the push ring 6 is moved upward from the radially inner end 8i of the interlocking arm 8. Because of the separation, the movement of the interlocking arm 8 from the radially outward position 8A to the radially inward position 8B is not restricted by the push ring 6, and the interlocking arm 8 enters a free state.

  In this free state, the operator grasps the interlocking arm 8 (for example, the handle portion, ie, the radially outer arm portion 8c), and moves the interlocking arm 8 inward in the radial direction against the biasing force of the biasing member 17. It is possible to move to the position 8B, and the movable lock member 9 is displaced from the lock position 9A to the unlock position 9B (FIG. 7) in accordance with the move operation. Thereby, since the latching state of the movable lock member 9 and the fixed lock member 10 is released, the opening operation of the cover C from the manhole closing position becomes possible at any time.

  As described above, in this embodiment, when the push ring 6 is moved upwardly from the tightening completion position 6A (FIG. 4) to the tightening release completion position 6B (FIG. 7) by rotating the operation lever 35, the push ring 6 is pushed. Until the ring 6 reaches at least the tightening start position 6X1 (FIG. 5), that is, there is no tightening force acting on the cover C from the push ring 6 via the restraining arm 7, and the residual pressure in the pressure tank T is reduced. Until sufficiently lowered, the push ring 6 can reliably hold the locking means L in the locked posture (that is, the movable locking member 9 at the locking position 9A) via the interlocking arm 8. Therefore, it is possible to reliably prevent the cover C from abruptly rising due to the residual pressure in the pressure tank T when the locking means L is half hooked, and the cover C and the tank are shocked by the sudden upward movement. It becomes possible to avoid effectively that each part of the main body Tm is damaged.

  In particular, the interlocking arm 8 of the interlocking mechanism I of the present embodiment starts tightening when the push ring 6 is operated from the tightening completion position 6A (FIG. 4) toward the tightening release completion position 6B (FIG. 7). Until the lock holding limit position 6X2 (FIG. 6) is deviated by a predetermined amount further from the position 6X1 (FIG. 5) to the tightening release side (that is, the upper side), that is, the residual pressure in the pressure tank T is more reliably secured. Until it comes off, the push ring 6 can reliably hold the locking means L in the locked posture via the interlocking arm 8. As a result, it is possible to more surely achieve the effect of preventing the sudden upward movement of the cover C by the lock means L, and the safety is further improved.

  Further, the cover holding member linked to the push ring 6 of the present embodiment is composed of a plurality of holding arms 7 arranged so as to extend radially from the center of the cover C. In the center of the cover C, a fastening completion position 6A and A single push ring 6 provided so as to be able to move up and down between the tightening release completion positions 6B can be engaged with and disengaged from the radially inner ends 7i of the plurality of holding arms 7. Therefore, the plurality of holding arms 7 can be simultaneously tightened or released by the same amount by one common push ring 6 of the tightening means P that is linked and coupled to the lock means L via the interlock mechanism I. The structure of the attaching means P can be simplified.

  Moreover, in the present embodiment, the radial sliding displacement of the interlocking arm 8 interlocked with the movable lock member 9 of the locking means L is accurately detected by the push ring 6 that can be engaged and disengaged with respect to the radially inner end 8i of the interlocking arm 8. Because it can be regulated and released, the push ring 6 of the tightening means P has a simple interlocking structure in which the movable lock member 9 is linked via the interlocking arm 8, and the locking means L and the push ring 6 are interlocked. Can be connected.

  Further, the interlocking arm 8 of the present embodiment has its radially inner arm portion 8b slidably abutting on the cover C, and from its radially inner arm portion 8b toward the movable lock member 9. The extending radially outer arm portion 8c can also be used as a handle portion protruding upward from the radially inner arm portion 8b. Thereby, since the radial direction inner side arm part 8b and the outer side arm part 8c of a single arm (interlocking arm 8) can be properly used for the sliding means on the cover C and the grip means, The handling is simple and further structural simplification can be achieved.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment, A various design change is possible in the range which does not deviate from the summary.

  For example, in the above-described embodiment, an example in which the pressure tank T is mounted on the granular material transport vehicle V has been described. However, the manhole cover mounting structure of the present invention has a pressure tank that is not mounted on the granular material transport vehicle (for example, It can also be applied to a manhole cover mounting structure in a pressure tank placed on the ground or a factory.

  In the above embodiment, the pressure tank T is mounted on the tank support (the vehicle body F in the case of the granular material transport vehicle V) so as to be able to tilt backward. However, the pressure tank T tilts to the tank support. It may be fixed impossible.

  In the above-described embodiment, the manhole cover C is opened and closed by opening and closing the tank body Tm while maintaining the horizontal posture through the parallel link mechanism LL, and further turning the manhole H about the vertical axis. However, the opening / closing support structure of the cover C is not limited to the embodiment. For example, the manhole H may be opened and closed by moving the cover C up and down through a horizontal pivot.

  Further, in the above-described embodiment, the tightening start position where the push ring 6 suppresses the lock holding limit position 6X2 that is the limit position on the tightening release side that holds the lock unit L in the locked posture and starts to apply the pressing force to the arm 7. Although an example in which the position is deviated by a predetermined amount from 6X1 to the tightening release completion position 6B side is shown, in the first feature of the present invention, the tightening start position 6X1 is set to coincide with the lock holding limit position. Also good. In this setting example, when the push ring 6 is displaced from the tightening start position 6X1 to the tightening release side, the push ring 6 loses the tightening force that acts on the cover C via the restraining arm 7, and at the same time, the locking means. An unlock operation for L can be performed.

  In the above embodiment, the holding arm 7 as a cover holding member is pivotally supported 37p on the tank body Tm (manhole forming cylinder 1). However, the holding arm of the present invention is disposed on the cover C side. The shaft may be pivotably supported. In this case, the holding arm is configured to apply a tightening force to the cover C by, for example, engaging the outer end thereof to the tank body Tm side (for example, Japanese Patent Publication No. 57-45948). See).

  In the above-described embodiment, the push ring 6 (push member) is engaged with the restraining arm 7 (cover restraining member) so as to be detachable. However, in the present invention, the push ring 6 (push member) is restrained. The arm 7 (cover holding member) may be connected. In this case, the position where the push ring 6 starts to apply a pressing force to the cover holding member via the connecting portion (in the case of Japanese Patent Publication No. 57-45948, the long groove 18a). Corresponds to the tightening start position 6X1.

  In the above embodiment, the fixed lock member 10 is provided on the tank body Tm side and the movable lock member 9 is provided on the cover C side. However, in the present invention, the fixed lock member 10 is provided on the cover C side. The movable lock member 9 may be provided on the tank body Tm side.

C ... Cover H ... Manhole I ... Interlocking mechanism L ... Locking means P ... Tightening means T ...・ Pressure tank Tm ... Tank body 1e ... Open upper end of manhole forming cylinder (open end of manhole)
6. Push ring (push member)
6A, 6B ··· Push ring tightening completion position, tightening release completion position 6X1, 6X2 · · Push ring tightening start position, lock holding limit position 7 ··· Holding arm (cover holding member)
7i: Radial inner end 8 of the holding arm 8 ... Interlocking arm 8A, 8B ... Radial outer position of the interlocking arm, radial inner position 8b ... Interlocking arm Radially inner arm portion 8c of the interlocking arm radially outward arm portion 8i of the interlocking arm radially inner end portion 9 of the interlocking arm. 9B .. Lock position of movable lock member, unlock position 10... Fixed lock member

Claims (6)

A tank body (Tm) capable of pressurizing the inside, a manhole (H) provided in the tank body (Tm), and a cover (C) attached to the tank body (Tm) so that the manhole (H) can be opened and closed In a mounting structure for a manhole cover in a pressure tank comprising: a tightening means (P) capable of applying a tightening force for tightening the cover (C) to the opening end (1e) of the manhole (H); A cover locking means (L) provided separately from the fastening means (P), and an interlocking mechanism (I) for interlocking the fastening means (P) and the locking means (L) with each other;
The locking means (L) can change its posture between a locking posture in which the cover (C) is locked to the tank body (Tm) at a manhole closing position and an unlocking posture in which the locking is released,
The fastening means (P) includes a push member (6) that can be arbitrarily moved between a fastening completion position (6A) and a fastening release completion position (6B), and a push member (6). A cover holding member (7) that applies a tightening force to the cover (C) in response to receiving pressure;
The interlocking mechanism (I) is provided between a tightening start position (6X1) at which the push member (6) starts to apply a pressing force to at least the cover holding member (7) and the tightening completion position (6A). In some cases, the push member (6) and the lock means (L) are interlocked and coupled so that the push means (6) holds the lock means (L) in the locked posture. Mounting structure for manhole cover in pressure tank.   The interlocking mechanism (I) includes a lock holding limit position (6X2) in which the push member (6) is displaced by a predetermined amount from the tightening start position (6X1) to the tightening release completion position (6B), and the tightening mechanism (I). When it is between the attachment completion position (6A), the push member (6) holds the locking means (L) in the locked position, but the push member (6) is in the lock holding limit position (6X2). When the push member (6) is located closer to the tightening release completion position (6B) than the push means (6), the push means (L) is allowed to change its position from the locked position to the unlocked position. The structure for mounting a manhole cover in a pressure tank according to claim 1, wherein the member (6) and the locking means (L) are linked and connected. The push member is a single push ring provided at the center of the cover (C) so that it can be moved up and down between the tightening completion position (6A) and the tightening release completion position (6B). 6),
The cover holding member is arranged to extend radially from the center of the cover (C) and is pivotally supported (37p) on the cover (C) or the tank body (Tm) so as to be swingable. It is composed of a plurality of holding arms (7) capable of converting the pressing force received from the push ring (6) into a tightening force to the cover (C) by swinging,
The push ring (6) is configured to be engageable with and disengageable from the radially inner ends (7i) of the plurality of holding arms (7), and the push ring (6) is in the tightening start position (6X1). When the push ring (6) is in the tightening completion position (6A), it is separated from the restraining arm (7) when it is closer to the tightening release completion position (6B). 7) is engaged so as to apply the pressing force, and further, while the push ring (6) moves from the tightening release completion position (6B) to the tightening completion position (6A). When the tightening start position (6X1) is reached, the push ring (6) starts engaging with the restraining arm (7) and starts to apply a pressing force to the cover restraining member (7). The manho in the pressure tank according to claim 2 The mounting structure of the Le for the cover. The lock means (L) includes a fixed lock member (10) fixed to one of the cover (C) and the tank body (Tm), and a lock position (9A) provided to either of the two. A movable lock member (9) movable between the unlock position (9B),
The movable lock member (9) locks the cover (C) to the manhole closed position by being locked to the fixed lock member (10) in the lock position (9A), and also the unlock position (9B). Then, it is configured to release the locking,
The interlocking mechanism (I) includes an interlocking arm (8) supported on the cover (C) so as to be movable between a predetermined radial outer position (A) and a radial inner position (8B). Have
The interlock arm (8) is in the radially outward position (8A) when the movable lock member (9) is in the locked position (9A), and the movable lock member (9) is unlocked. When in the position (9B), the movable lock member (9) is interlocked and connected so as to be in the radially inner position (8B),
The radially inner end portion (8i) of the interlocking arm (8) and the outer peripheral portion of the push ring (6) are configured to be detachable from each other, and the push ring (6) is in the lock holding limit position. (6X2) and the fastening completion position (6A), the interlocking arm (8) is held at the radially outward position (8A) by the push ring (6). When the push ring (6) is closer to the tightening release completion position (6B) than the lock holding limit position (6X2), the interlocking arm (8) is released from the push ring (6), The manhole cover in a pressure tank according to claim 3, characterized in that movement of the interlocking arm (8) from the radially outer position (8A) to the radially inner position (8B) is allowed. Mounting structure. The interlocking arm (8) includes a radially inner arm portion (8b) that abuts on the cover (C) so as to be slidable in the radial direction, and the movable lock from the radially inner arm portion (8b). A radially outward arm portion (8c) extending toward the member,
5. The pressure according to claim 4, wherein the radially outer arm portion (8 c) can be used as a handle portion protruding upward from the radially inner arm portion (8 b). Manhole cover mounting structure in the tank. A granular material transport vehicle comprising a manhole cover mounting structure in a pressure tank according to any one of claims 1 to 5,
The granular material transport vehicle, wherein the pressure tank (T) capable of accommodating the granular material is mounted on a vehicle body (F).

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