JP5518809B2 - Locking structure for lids for underground structures - Google Patents

Description

  The present invention relates to a locking structure for a lid for an underground structure such as a manhole cover or a sewage jar cover.

  Conventionally, as a lid for an underground structure of this type, a receiving frame disposed in an opening portion of the ground surface that leads to an underground structure (for example, a common ditch or a sewer pipe), and a lid body that can be opened and closed by the receiving frame And a locking structure for locking the lid to the receiving frame is known (see, for example, Patent Document 1). Generally, this locking structure is such that a pendulum-like locking body is pivotally supported on the lower surface of the lid body, and an engaging projection formed on the locking body is formed on the inner peripheral portion of the receiving frame by its own weight. The structure engages. And according to this locking structure, the locking body is rocked by inserting the opening tool into the tool insertion port formed in the peripheral edge of the lid body to release the locking, and the lid body is pulled up in this state. Thus, the lid can be opened.

No. 7-56357

  However, in the locking structure as described above, the locking body faces the tool insertion slot when locking, and the locking body can be easily swung in the unlocking direction through the tool insertion slot. There is a risk that outsiders who do not have a lid tool may pry open the lid using a commercially available crane or metal rod.

  The present invention has been made to solve the above-described problem, and locking a lid for an underground structure that can prevent the lid from being illegally opened by a member other than a dedicated opening tool. The purpose is to provide a structure.

In order to achieve the above object, the invention of claim 1 is to lock a lid for an underground structure, comprising a receiving frame, a lid body that can be opened and closed by the receiving frame, and a lock for locking the lid body. An opening for inserting a lid opening tool is provided at a peripheral edge portion of the lid body, and the receiving frame has a concave lock seat with an opening formed on an inner peripheral surface. , Pivotally supported on the lower surface of the lid in the inner circumferential direction of the opening, and engaging protrusions engaged with the lock seat when locked, facing the opening when locked, and pressed when unlocked An unlocking protrusion, and when the protrusion is pressed by a crane or bar member other than a dedicated opening tool, the tip of the member is fitted into the unlocking protrusion. Mari crowded in a recessed portion is formed in a mortar shape constrained so as not to reach the periphery of the opening of the lid, the dedicated lid opening tool, a hook portion at the tip By tilting the lid opening tool to the outer peripheral side of the lid body while pressing the projecting piece in the bar shape, the tip end of the flange portion is not restrained by the concave portion, and the inner peripheral direction of the opening portion It is characterized in that it enters and is pulled up by hooking the periphery of the opening .

  In the locking structure for the lid for an underground structure, the lock is a spring member that constantly urges the lock to rotate in the locking direction, and the engagement protrusion and the unlocking mechanism around the axis. It is preferable to provide a weight that balances the weight of the protruding piece.

  According to the locking structure for an underground structure lid of the present invention, even when a member other than a dedicated opening tool is inserted into the opening of the lid and the unlocking protrusion is pressed, the tip of the member Fits into the recess and cannot be inserted to the periphery of the opening of the lid, so that it is possible to prevent the lid from being opened by a malicious third party who does not have a dedicated opening tool.

The top view which shows the locking structure of the lid | cover for underground structures which concerns on one Embodiment of this invention. FIG. 2 is a sectional view taken along line AA in FIG. 1. Sectional drawing of the principal part containing the lock | rock of the locking structure. The side view of the arrow B direction in FIG. (A) thru | or (f) is sectional drawing which shows the opening procedure of the cover for the underground structures. (A) And (b) is sectional drawing which shows the state of a lock | rock when a member other than a dedicated opening tool is inserted in the opening part of the cover for underground structures in time series.

A locking structure for an underground structure lid according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 4 , the locking structure 1 for a lid for an underground structure has a ring-shaped receiving frame 2 installed at an open end of the ground surface that leads to the underground structure, and a taper fit to the inner peripheral surface of the receiving frame 2 The lid body 3 is held by the above, and the lock 4 for locking the lid body 3 is provided. The receiving frame 2 has a stepped opening 21 large enough to fit the lid 3, and the inner peripheral surface on the upper side forming the stepped opening 21 becomes smaller in diameter from the upper end toward the lower end. It is tapered. The receiving frame 2 has a lock seat 22 at a position corresponding to the lock 4 on the lower side of the inner peripheral surface thereof. When the lock seat 22 is to be opened without unlocking (rotating) the lock 4 from the state in which the lid 3 is closed, the engagement protrusion 41 formed on the lock 4 is engaged and opened. Block the lid. The lid 3 is made of a disk member having an outer peripheral surface having the same inclination angle as the tapered surface of the stepped opening 21 of the receiving frame 2, and is connected to the receiving frame 2 so as to be opened and closed by a hinge 5 provided on the lower surface thereof. Yes. An opening 31 for inserting an opening tool is provided at the peripheral edge of the lid 3. The opening 31 is formed in a substantially semicircular shape in the peripheral edge of the lid 3 opposite to the side where the hinge 5 is provided, and a part of the peripheral edge is notched. In addition to the opening 31 described above, a small hole 32 for cutting off the lid 3 and the receiving frame 2 when the lid is opened is provided in the peripheral portion of the lid 3. The lock 4 is pivotally supported on the lower surface of the lid 3 in the inner peripheral direction of the opening 31 so as to be swingable.

The lock 4 includes an engagement protrusion 41 that engages with the lock seat 22 of the receiving frame 2 at the time of locking, an unlocking protrusion 42 that faces the opening 31 of the lid 3 at the time of locking and is pressed at the time of unlocking. And a main body 43 on which arms 43a and 43b for holding the engaging protrusion 41 and the protruding piece 42 are formed. The main body 43 has swinging shafts 44 projecting sideways on both sides of the upper portion thereof. The swing shaft 44 is pivotally supported by a pair of support side walls 33 formed on the lower surface of the lid 3. The engagement protrusion 41 is formed to protrude upward at one end of an arm 43 a extending obliquely downward from the upper part of the main body 43, and can be engaged with the lock seat 22. The projecting piece 42 is provided at one end of an arm 43 b that extends from the upper part of the main body 43 to the front (the outer peripheral side of the lid 3). A concave portion 42a that restrains the projecting piece 42 so that when the projecting piece 42 is pressed by a member other than a dedicated lid opening tool, the tip of the member is fitted and does not reach the periphery of the opening of the lid 3. Is formed. The recess 42a has a mortar shape in which the tip of a member other than a dedicated opening tool is guided.

  In addition, the lock 4 has a spring member 45 (not shown in FIG. 4) that constantly urges the lock 4 to rotate in the locking direction around the swing axis, an engagement protrusion 41 and an unlocking protrusion about this axis. And a weight 46 that balances the weight of 42. The spring member 45 is formed of a torsion spring, the central axis is fitted to the swing shaft 44, one side is locked to the lower surface on the inner side of the swing shaft 44 of the lid 3, and the other side is the arm 43a. It is latched on the rear surface. The weight 46 is provided at a rear portion of the main body 43.

Next, the procedure for opening the lid body 3 in the locking structure 1 for the underground structure lid configured as described above will be described with reference to FIG. As shown in FIG. 5A, when the lid 3 is fitted to the receiving frame 2, the lock 4 is urged in the direction of arrow A by the spring force of the spring member 45 and the weight of the weight 46. . At this time, even if the opening operation is performed without the lock 4 being rotated, the engagement protrusion 41 is engaged with the lock seat 22 and the lock is held . The unlocking projecting piece 42 faces the opening 31 so as to be at the same height as the upper surface of the lid 3 in the locking position, whereby the opening 31 is closed.

When opening the lid 3, a dedicated opening tool 10 is used. The opening tool 10 has a bar shape having a flange 10a for pulling up the lid 3 at the tip. First, the opening tool 10 is inserted into the opening 31 of the lid 3 and the unlocking protrusion 42 is pressed. Since the tip of the opening tool 10 is a flange 10a, it is not restrained by the recess 42a of the projecting piece 42. When the unlocking protrusion 42 is pressed, the lock 4 rotates in the direction of arrow B with the swing shaft 44 as a fulcrum against the urging of the spring member 45 as shown in FIG. Move. At this time, the engaging projection 41 is separated from the lock seat 22, locking of the lid 3 is unlocked. Next, as shown in FIG. 5 (c), when the lid opening tool 10 is tilted in the direction of arrow C while pressing the projecting piece 42, the tip of the lid opening tool 10 is directed in the inner circumferential direction of the opening 31. Be guided to get in. As shown in FIG. 5 (d), when the opening tool 10 is further tilted in the direction of arrow C and the tip is inserted deeply into the inner circumferential direction of the opening 31, the periphery of the opening of the lid 3 is opened. The lid tool 10 is hooked by the flange portion 10a. At this time, the protrusion 10 b formed on the opening tool 10 is brought into contact with the upper surface of the receiving frame 2. Next, as shown in FIG. 5E, in the state where the protrusion 10b of the opening tool 10 is in contact with the upper surface of the receiving frame 2, the opening tool 10 is tilted with the contact portion as a fulcrum. When lifted in the direction, as shown in FIG. 5 (f) , the lid 3 is pulled up from the receiving frame 2 without the engaging protrusion 41 engaging the lock seat 22 .

  Next, in the locking structure 1 for an underground structure lid configured as described above, an operation for preventing unauthorized unlocking of the lid by a member other than a dedicated opening tool will be described with reference to FIG. In the present locking structure 1, the lid 3 can be easily opened by using the dedicated opening tool 10 having the collar portion 10 a at the tip as described above, but the lid opening tool not having the collar portion 10 a. When a member other than (for example, a crane or a metal rod) is used, the lid 3 cannot be opened. That is, as shown in FIG. 6A, when trying to press the projecting piece 42 by the member 11 other than the opening tool, the tip of the member 11 fits into the recess 42 a of the projecting piece 42, Movement in the inner circumferential direction is restricted. Therefore, in the member 11 other than the opening tool, as shown in FIG. 6B, even if the engagement state between the engagement protrusion 41 and the lock seat 22 can be released by pressing the protrusion 42, the tip of the member 11 Is not allowed to be inserted deeply into the inner circumferential direction of the opening 31, and the opening peripheral edge of the lid 3 cannot be hooked and pulled up.

  As described above, according to the underground structure lid locking structure 1 according to the present embodiment, the member 11 other than the dedicated opening tool is inserted into the opening 31 of the lid 3, and the unlocking protrusion 42 is provided. Even if pressed, the tip of the member 11 is fitted into the recess 42a and cannot be inserted to the periphery of the opening of the lid 3, so that the lid 3 is opened by a malicious third party who does not have a dedicated opening tool. It can be prevented from being covered.

  In addition, this invention is not restricted to the structure of the said embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. For example, the lid for an underground structure is not limited to a circular manhole, but may be a rectangular lid and a receiving frame that supports the lid.

DESCRIPTION OF SYMBOLS 1 Locking structure of a cover for underground structures 2 Receiving frame 3 Lid body 31 Opening part 4 Lock 41 Engagement protrusion 42 Protrusion piece 42a Recess 45 Spring member 46 Weight 10 Opening tool 11 Members other than the opening tool

Claims (2)

A locking structure for a lid for an underground structure, comprising a receiving frame, a lid body that can be opened and closed by the receiving frame, and a lock for locking the lid body,
An opening for inserting a lid opening tool is provided at the peripheral edge of the lid,
The receiving frame has a concave lock seat with an opening formed on the inner peripheral surface,
The lock is pivotally supported on the lower surface of the lid body in the inner circumferential direction of the opening, and engages with the lock seat when locked, and faces the opening when locked, and when unlocked. And an unlocking protrusion to be pressed,
When the projecting piece is pressed down by a crane or bar member other than a dedicated opening tool, the tip of the member is fitted into the unlocking projecting piece and is placed on the periphery of the opening of the lid. A mortar-shaped recess that is constrained so as not to reach is formed ,
The dedicated opening tool has a bar shape having a collar at the tip, and the tip of the collar is moved by tilting the lid opening tool toward the outer periphery of the lid while pressing the protruding piece. A locking structure for a lid for an underground structure, wherein the structure is inserted into the inner circumferential direction of the opening without being restrained by the recess, and is hooked up and pulled up around the periphery of the opening . The lock is a weight that balances the weight of a spring member that constantly rotates and urges the lock in the locking direction, and the weight of the engaging protrusion and the unlocking protrusion with respect to the axis. The locking structure for a lid for an underground structure according to claim 1 .

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