JP5480038B2 - Ceramic insert and its manufacturing method - Google Patents

Description

  The present invention relates to a ceramic insert and a method for manufacturing the same, and is embedded in a concrete product such as a track slab or a floor slab. The concrete product is removed from the formwork, or is transported after being removed or installed in a service place, for example, a track slab. This is for screwing bolts or I bolts to be engaged with the hooks of the crane during installation on the track floor, etc., and its opening surface can be securely closed with screw plugs, and female screws for bolts And a female screw for a screw plug on the same axis so that they can be selected and used.

  Conventionally, the present applicant has applied for a ceramic insert in which the deformed portion 6 is formed on the outer peripheral surface in order to increase the pull-out resistance. (For example, Unexamined-Japanese-Patent No. 2008-101441).

JP 2008-101441 A (see paragraph 0023, FIG. 1)

  The invention described in Patent Document 1 is one in which the head 1 and the sleeve portion 2 are integrally formed to eliminate joints and prevent intrusion of rainwater, and the outer surface deformation portions 6 and 7 increase the resistance to slipping. A simple plastic cap is fitted into the closed open surface 5. For this reason, when the concrete product is installed in a place where vibration is received, the cap loosens and sewage enters and closes the female screw, and in severe cases, the cap may come off the opening surface and the shaft hole may be exposed.

  An object of the present invention is to provide a ceramic insert and a method for manufacturing the ceramic insert that can be selectively used by making it possible to reliably close the opening surface with a screw plug, and by separating the female screw for bolt and the female screw for screw plug on the axis. With the goal.

   (Claim 1) The ceramic insert according to the present invention has a deformed outer peripheral surface and a bolt hole on the axis. The bolt hole has an opening surface at the outer end, the inner end is closed by an end wall, a female screw for screwing on the opening surface side of the peripheral wall surface, and a bolt on the end wall side with an intermediate portion interposed therebetween It has a female thread for screwing. The pitch of the two female screws is the same, the root diameter of the female screw on the end wall side is the same as or smaller than the inner diameter of the intermediate portion, and the inner diameter of the female screw on the opening surface side is the same or larger than the inner diameter of the intermediate portion. ing.

  The irregular surface has a shape in which the outer diameter is small on the opening surface side and the outer diameter is large on the side opposite to the opening surface side, so that it can resist a large tensile force acting on the opening surface side. . The bolt hole is of an inner end closed type, and has an internal thread that is screwed with a screw plug on the opening surface side, an internal thread that is screwed with a bolt on the inner end side, and the space between both female screws is an intermediate portion of the cylindrical space. Since these female screws have the same pitch, if each male screw is provided on the same shaft member, the male screw is screwed with each female screw by rotating this shaft member, or Can be withdrawn.

  In addition, the valley diameter of the female screw on the end wall side is the same as or smaller than the inner diameter of the intermediate portion, and the inner diameter of the female screw on the opening side is the same as or larger than the inner diameter of the intermediate portion. When the screw is inserted into the bolt hole and screwed into the female screw at the inner end, it does not interfere with the female screw or the intermediate portion on the opening surface side, and the insertion is easy and the screwing operation is also easy.

(Claim 2) The female screw for engaging the screw plug may be a trapezoidal screw.
This increases the contact area of the female and male screws, and the screw plug is firmly screwed into the female screw, so that even if the concrete product is subjected to strong vibration, it does not come out of the opening surface.

(Claim 3) The irregular shape includes a cylindrical portion having a uniform outer diameter on the opening surface side, a bullet-shaped portion having an outer diameter gradually increasing from the opening surface side on the end wall side toward the end wall side, It includes a conical cylindrical portion between the cylindrical portion and the bullet-shaped portion, with a small-diameter portion passing through the truncated cone portion following the cylindrical-shaped portion, and a large-diameter portion continuing through the stepped portion into the bullet-shaped portion. May be.
In this way, even if a pulling force is applied to the insert by applying a tensile force to the bolt screwed into the insert, it resists at the outer peripheral surface of the conical cylindrical portion forming the deformed surface and the bullet-shaped portion, Prevent escape from concrete products.

(Claim 4) The conical cylindrical portion may be provided on the outer peripheral surface with a rib projecting radially from the outer peripheral surface and having one end reaching the cylindrical portion beyond the truncated cone portion.
Thus, even if a load in a direction perpendicular to the axis is applied to the cylindrical part by applying an offset load to the bolt screwed to the insert at an angle with the axis, the cylindrical part is reinforced by the rib. Therefore, there is no fear of cracking or breaking, and this rib also acts as a detent for the insert.

  (Claim 5) The present invention is a method for producing the ceramic insert. It has a male threaded part at one end on the axis, has a male threaded part on the opposite side across the cylindrical intermediate part from the one end, the pitch of both male threaded parts is the same, and the outer diameter of the intermediate part is A mandrel that is larger than the outer diameter of the male screw portion on the one end side and smaller than the outer diameter of the male screw portion on the opposite side is used. The ceramic material is fired by covering the one end portion of the mandrel and the other male screw portions and forming the outer peripheral surface into a deformed surface. Then, the fired ceramic material is turned off from the mandrel. The meaning of this turning is to separate the ceramic material and the mandrel by rotating them relatively on the same axis.

  The fired ceramic material forms a female screw at a portion covering each other male screw portion of the same pitch of the mandrel, and when the ceramic material is removed from the mandrel by a turning operation of the mandrel An insert with a female screw for a bolt and a female screw for a screw plug appears.

(Claim 6) The male screw portion on the opposite side may be a trapezoidal screw.
This increases the contact area of the female and male screws, so that the screw plugs are firmly screwed into the female screws and do not come out of the openings even when the concrete product is subjected to strong vibration.

  (Claim 1) According to the ceramic insert of the present invention, since the outer peripheral surface is a deformed surface and is provided with a bolt hole on the axis, it is possible to resist a large tensile force acting on the opening surface side. It has an opening surface at the outer end, the inner end is closed by an end wall, a female screw for screwing on the opening surface side of the peripheral wall surface, and a female screw for bolt screwing on the end wall side with an intermediate portion interposed therebetween The pitch of the female screws is the same, the valley diameter of the female screw on the end wall side is the same as or smaller than the inner diameter of the intermediate portion, and the inner diameter of the female screw on the opening surface side is the same or larger than the inner diameter of the intermediate portion Therefore, if each male screw screwed to each female screw is provided on the same shaft member, by rotating this shaft member, each male screw can be screwed or detached from each female screw. It is possible to insert concrete product operation bolts into the bolt holes and internal threads When screwing, not interfere with the internal thread and an intermediate portion of the opening side, it can be easily inserted, screwing work if easily.

  According to the second aspect, since the female screw for engaging the screw plug is a trapezoidal screw, the contact area of the female screw is increased, the screw plug is tightly engaged with the female screw, and the concrete product is subjected to strong vibration. However, it does not escape from the opening surface.

  According to claim 3, the deformed surface has a cylindrical portion having a uniform outer diameter on the opening surface side, and a bullet-like shape whose outer diameter gradually increases from the opening surface side on the end wall side toward the end wall side. A conical cylindrical portion between the cylindrical portion and the bullet-shaped portion, the small-diameter portion via the truncated cone portion following the cylindrical portion, and the large-diameter portion following the bullet-shaped portion via the stepped portion. Therefore, even if a pulling force is applied to the insert by applying a tensile force to the bolt screwed into the insert, the outer peripheral surface of the conical cylindrical portion and the bullet-shaped portion forming a deformed surface. Resist and prevent escape from concrete products.

  According to claim 4, the conical cylindrical portion is provided on the outer peripheral surface with a rib projecting radially from the outer peripheral surface and having one end reaching the cylindrical portion beyond the frustoconical portion. By applying an offset load to the combined bolt at an angle with the axis, there is no risk of cracking or breaking even if a load perpendicular to the axis is applied to the cylindrical part. It also functions as a rotation stopper.

  According to the method for producing a ceramic insert of claim 5, a male screw portion similar to a bolt is provided at one end on the axis, and a male screw portion similar to a screw plug is provided on the opposite side across a cylindrical intermediate portion from the male screw portion. And the external thread of the middle part is larger than the outer diameter of the male thread part on the one end side and smaller than the outer diameter of the male thread part on the opposite side. A ceramic material covering the one end portion of the mandrel and each of the other male screw portions and forming the outer peripheral surface into a deformed surface, and firing the ceramic material from the mandrel. Thus, the fired ceramic material forms a female screw at a portion of the mandrel that covers the other male screw portion of the same pitch, and the ceramic material is turned by rotating the mandrel. Remove the mandrel from the book It is possible to provide a Ming insert.

  According to claim 6, since the male screw portion on the opposite side is a trapezoidal screw, the contact area of the female male screw is increased, the screw plug is firmly screwed into the female screw, and the concrete product is subjected to strong vibration. Even if it is received, it does not escape from the opening surface.

It is a front view which shows the specific example of the ceramic insert concerning this invention. It is a top view. Is a sectional view taken along line 3-3 in FIG. Is an enlarged view of part A in FIG. FIG. 3B is an enlarged view of a portion B in FIG. 3A. It is the schematic which shows the manufacturing method of the ceramic insert concerning this invention.

Embodiments of the present invention will be described below with reference to the drawings.
(Claim 1) FIG. 1 is a front view of a ceramic insert according to the present invention. This insert has a deformed surface 1 on the outer peripheral surface and a bolt hole 2 on the axis X. The bolt hole 2 has an opening surface 3 at an outer end, an inner end is closed by an end wall 4, a female screw 6 for screwing with a screw plug C on the opening surface 3 side of the peripheral wall surface 5, and a cylindrical shape A female screw 8 for screwing with the bolt T is provided on the side of the end wall 4 with the intermediate portion 7 forming the space portion therebetween.
Both the pitch P of the internal thread 6 and 8 are the same and the root diameter d ₁ of the end wall 4 side of the internal thread 8 is equal to or smaller as the inner diameter d ₂ of the intermediate portion 7, the inside diameter d ₃ of the internal thread 6 of the opening surface 3 side intermediate It is the same as or larger than the inner diameter d _{2 of the} portion 7.

  The deformed surface 1 has a shape in which the outer surface has a small outer diameter on the opening surface 3 side and a large outer diameter on the end wall 4 side so that it can resist a large tensile force acting on the opening surface 3 side. Yes. The bolt hole 2 is an inner end closed type, and has an internal thread 6 that is screwed with the screw plug C on the opening surface 3 side, an internal thread 8 that is screwed with the bolt T on the inner end side, and a cylindrical shape between both the female screws 6 and 8. It is the middle part 7 of the space. Since these female screws 6 and 8 have the same pitch P, if each male screw 6 is provided on the mandrel M to be screwed with the female screw 6 or 8, the male screw is rotated by rotating the dodrel M. 6 or 8 can be screwed or detached.

Further, the root diameter d ₁ of the end wall 4 side of the internal thread 8 is equal to or smaller as the inner diameter d ₂ of the intermediate portion 7, the inside diameter d ₃ of the internal thread 6 of the opening surface 3 side are the same or as large as the inner diameter d ₂ of the intermediate portion 7 Therefore, when the bolt T for operating the concrete product K is inserted into the bolt hole 2 and screwed into the female screw 8 at the inner end, it does not interfere with the female screw 6 or the intermediate portion 7 on the opening surface 3 side. , Easy to insert and easy to screw.

  In the drawing, reference numeral 41 denotes a flat surface portion formed at the enlarged diameter end portion of the bullet-like portion 22 with a detent.

(Claim 2) The female screw 6 for engaging the screw plug C is a trapezoidal screw.
In this case, since the contact area of the male and female screws is increased, the screw plug C is firmly screwed into the female screw 6 and the concrete product does not come out of the opening even if the concrete product is subjected to strong vibration.

(Claim 3) profiled surface 1 is uniformly cylindrical portion 21 of the outer diameter D ₁ of the opening surface 3 side, increasing the outer diameter D ₂ toward the opening surface 3 side of the end wall 4 side to the end wall 4 side The bullet-shaped portion 22 between the cylindrical portion 21 and the bullet-shaped portion 22 is formed by the small-diameter portion 23a via the truncated cone portion 24 and the cylindrical portion 21 followed by the large-diameter portion 23b via the step portion 25. Conical cylindrical portion 23 is included.
In this case, even if a pulling force is applied to the insert by applying a tensile force to the bolt screwed to the insert, the outer peripheral surface of the conical cylindrical portion 23 and the bullet-shaped portion 22 forming the deformed surface 1 resists, Prevent the concrete product K from slipping out.

(Claim 4) The conical cylindrical portion 23 is provided with a rib 31 protruding radially from the outer peripheral surface and having one end reaching the cylindrical portion 21 beyond the truncated cone portion 24 on the outer peripheral surface.
In this case, even if a load in a direction perpendicular to the axis X is applied to the cylindrical portion 21 by applying an offset load to the bolt T screwed to the insert at an angle with the axis X, the cylindrical portion 21 is Since it is reinforced, there is no risk of cracking or breaking, and the rib 31 also acts as a detent for the insert.

(Claim 5) In the method for producing a ceramic insert according to claim 1, the mandrel M is used. The mandrel M has a male threaded portion 62 at one end 61 on the axis X ₁ , and has a male threaded portion 64 on the opposite side across the cylindrical intermediate portion 63 from the one end 61. 64 pitch P outer diameter D ₃ of the same as and the intermediate portion 63 of the larger than the outer diameter D ₄ of the one end portion 61 side of the external thread portion 62, becomes smaller than the outer diameter D ₅ of the opposite side of the external thread portion 64 Yes. The mandrel M is fired with the ceramic material S covering the one end portion 61 and the other male screw portions 62 and 64 and the outer peripheral surface of the deformed surface 1, and the fired ceramic material S is turned off from the mandrel M.
In this case, the fired ceramic material S forms the internal threads 6 and 8 at portions of the mandrel M covering the different external thread portions 62 and 64 having the same pitch, and the mandrel M is swung. When the ceramic material S is removed from the mandrel M, an insert including the female screw 8 for the bolt T and the female screw 6 for the screw plug C appears.

(Claim 6) The male screw portion 64 on the opposite side is a trapezoidal screw.
In this case, since the contact area of the male and female screws is increased, the screw plug C is firmly screwed into the female screw 6 and does not come out of the opening surface 3 even if the concrete product K receives strong vibration.

DESCRIPTION OF SYMBOLS 1 Modified surface X Axis 2 Bolt hole 3 Opening surface 4 End wall 5 Circumferential wall C Screw 6 Female thread 7 Middle part 8 Female thread P Pitch d ₁ Valley diameter d ₂ Inner diameter d ₃ Inner diameter 21 Cylindrical part 22 Cannonball-shaped part 23 Conical cylindrical shape Portion 23a small diameter portion 23b large diameter portion 24 truncated cone portion 25 stepped portion 31 rib X ₁ axis 61 one end portion 62 male screw portion 63 intermediate portion 64 male screw portion D ₃ outer diameter D ₄ outer diameter D ₅ outer diameter M mandrel S ceramic material

Claims (6)

The outer peripheral surface is a deformed surface (1) and has a bolt hole (2) on the axis (X).
The bolt hole (2) has an opening surface (3) at the outer end, the inner end is closed by the end wall (4), and a screw plug (C) screw is formed on the opening surface (3) side of the peripheral wall surface (5). Has a female screw (6) for fitting, and has a female screw (8) for screwing a bolt (T) on the side of the end wall (4) across the intermediate part (7),
The pitch (P) of both the female screws (6, 8) is the same, and the root diameter (d ₁ ) of the female screw (8) on the end wall (4) side is the same as the inner diameter (d ₂ ) of the intermediate portion (7). A ceramic insert characterized in that the inner diameter (d ₃ ) of the female screw (6) on the opening surface (3) side is the same or larger than the inner diameter (d ₂ ) of the intermediate portion (7). .   The ceramic insert according to claim 1, wherein the female screw (6) for engaging the screw plug (C) is a trapezoidal screw. The deformed surface (1) includes a cylindrical portion (21) having a uniform outer diameter (D ₁ ) on the opening surface (3) side, and the end surface from the opening surface (3) side on the end wall (4) side. bullet-shaped portion for increasing the outer diameter (D ₂₎ towards the wall (4) side (22), said cylindrical portion (21) and該砲bullet-shaped portion between (22), frustoconical in small diameter portion (23a) Including the cylindrical part (23), following the cylindrical part (21) via the part (24) and following the bullet-like part (22) via the step part (25) at the large diameter part (23b) The ceramic insert according to claim 1 or 2.   The conical cylindrical portion (23) is provided on the outer peripheral surface with a rib (31) protruding radially from the outer peripheral surface and having one end reaching the cylindrical portion (21) beyond the truncated cone portion (24). The ceramic insert according to claim 3. In preparation of ceramic insert according to claim 1, the axis (X ₁₎ at one end (61) on a male screw portion (62), a cylindrical middle portion from the one end (61) (63) the has a male screw portion (64) on the opposite side, the outer diameter (D ₃₎ of the pitch (P) same as and intermediate portion (63) of both said male screw portion (62, 64) is the end portion The mandrel (M) which is larger than the outer diameter (D ₄ ) of the male screw part (62) on the (61) side and smaller than the outer diameter (D ₅ ) of the male screw part (64) on the opposite side. The ceramic material (S) covers the one end portion (61) and each of the other male screw portions (62, 64), and the outer peripheral surface is formed into a deformed surface (1) and fired, and the fired ceramic material (S ) From the mandrel (M).   The method for producing a ceramic insert according to claim 5, wherein the male screw portion (64) on the opposite side is a trapezoidal screw.

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