阅读说明：本技术 铁道车辆用门扇、紧固构造和铁道车辆用门扇的制造方法 (Door leaf for railway vehicle, fastening structure, and method for manufacturing door leaf for railway vehicle ) 是由 佐藤数马 佐藤孝治 于 2021-04-15 设计创作，主要内容包括：本发明的课题在于提供一种容易制造的铁道车辆用门扇、紧固构造和铁道车辆用门扇的制造方法。铁道车辆用门扇具备自攻螺钉,该自攻螺钉一边贯穿纵框而对设置到横框的底孔(30)进行攻丝一边向该底孔(30)拧入,从而将纵框和横框紧固。横框的形成底孔(30)的壁具有在与自攻螺钉的轴向正交的面中与自攻螺钉接触的接触区域(A1)和不与自攻螺钉接触的非接触区域(A2)。(The invention provides a door leaf for a railway vehicle, a fastening structure and a method for manufacturing the door leaf for the railway vehicle, which are easy to manufacture. A door leaf for a railway vehicle is provided with a tapping screw which is screwed into a bottom hole (30) provided to a transverse frame while penetrating through a vertical frame and tapping the bottom hole (30), thereby fastening the vertical frame and the transverse frame. The wall of the lateral frame forming the bottom hole (30) has a contact region (A1) which is in contact with the tapping screw in a surface orthogonal to the axial direction of the tapping screw, and a non-contact region (A2) which is not in contact with the tapping screw.)

1. A door leaf for a railway vehicle, which is a door leaf for a railway vehicle comprising a1 st member and a2 nd member, wherein,

the door leaf for a railway vehicle is provided with a tapping screw which screws into an under-hole provided in the 2 nd member while tapping the under-hole to fasten the 1 st member and the 2 nd member,

the wall of the 2 nd member forming the pilot hole has a non-contact region that does not contact the tapping screw in a plane orthogonal to the axial direction of the tapping screw.

2. The door leaf for a railway vehicle according to claim 1,

the non-contact region is a portion located on the outer side of the thread diameter of the tapping screw in a plane orthogonal to the axial direction of the tapping screw.

3. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the wall forming the pilot hole has a contact area that comes into contact with the tapping screw in a plane orthogonal to the axial direction of the tapping screw,

among the walls of the contact region, a wall in the circumferential direction of the tapping screw is parallel to the circumference of an imaginary circle having a diameter equal to the thread diameter of the tapping screw and centered on the center of the pilot hole in a plane orthogonal to the axial direction of the tapping screw.

4. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the wall forming the pilot hole has a contact area that comes into contact with the tapping screw in a plane orthogonal to the axial direction of the tapping screw,

the wall surface of the contact region includes, in a surface orthogonal to the axial direction of the tapping screw, a portion located outside an imaginary circle having a diameter equal to the thread root diameter of the tapping screw with the center of the pilot hole as the center.

5. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the walls forming the bottomed hole are disposed point-symmetrically with respect to the central axis of the bottomed hole as a center.

6. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the non-contact region is provided on 20% to 80% of the circumference of the thread diameter of the tapping screw in a surface orthogonal to the axial direction of the tapping screw.

7. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the volume that is not tapped in the volume sandwiched between the thread diameter and the thread root diameter of the tapping screw is 20% to 80%.

8. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

as for the wall forming the bottom hole,

the 1 st position includes a1 st contact region that is to be contacted by the tapping screw and a1 st non-contact region that is not to be contacted by the tapping screw in a face orthogonal to the axial direction of the tapping screw,

a2 nd position located closer to the tip end side of the tapping screw than the 1 st position in the axial direction of the tapping screw includes a2 nd contact region that is in contact with the tapping screw in a surface orthogonal to the axial direction of the tapping screw and a2 nd non-contact region that is not in contact with the tapping screw,

the ratio of the 1 st non-contact area to the sum of the 1 st contact area and the 1 st non-contact area is higher than the ratio of the 2 nd non-contact area to the sum of the 2 nd contact area and the 2 nd non-contact area.

9. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the non-contact region is provided in a partial region in an axial direction of the tapping screw.

10. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the non-contact region is further provided with a receiving portion for receiving chips generated when the tapping screw is tapped.

11. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

the 2 nd member having the bottom hole is manufactured by extrusion molding.

12. The door leaf for a railway vehicle according to claim 1 or 2, wherein,

one of the 1 st member and the 2 nd member is a frame body as a vertical frame, and the other of the 1 st member and the 2 nd member is a frame body as a horizontal frame.

13. The door leaf for a railway vehicle according to claim 12,

the 1 st member is a vertical frame, and the 2 nd member is a horizontal frame.

14. A fastening construction between a1 st member and a2 nd member, wherein,

the fastening structure includes a tapping screw that screws into a pilot hole provided in the 2 nd member while tapping the pilot hole to fasten the 1 st member and the 2 nd member,

the wall of the 2 nd member forming the pilot hole has a non-contact region that does not contact the tapping screw in a plane orthogonal to the axial direction of the tapping screw.

15. A method of manufacturing a door leaf for a railway vehicle, the door leaf for a railway vehicle comprising a1 st member and a2 nd member, wherein,

the wall forming the bottomed hole provided to the 2 nd member has a non-contact region that does not contact the tapping screw in a face orthogonal to the axial direction of the tapping screw screwed into the bottomed hole,

screwing in the tapping screw while tapping the pilot hole of the 2 nd member, thereby fastening the 1 st member and the 2 nd member.

Technical Field

The invention relates to a door leaf for a railway vehicle, a fastening structure and a method for manufacturing the door leaf for the railway vehicle.

Background

A conventional door for a railway vehicle includes a frame body including an upper edge frame, a lower edge frame, a door head edge frame, and a door tail edge frame (see, for example, japanese patent application laid-open No. 4-57481).

In the case described in japanese patent application laid-open No. 4-57481, the door head side edge frame and the door tail side edge frame extend in the vertical direction, which is the longitudinal direction of the door, and the upper edge frame and the lower edge frame extend in the horizontal direction, which is the short direction of the door. The door is provided with an inner vehicle panel on the inner vehicle side of the frame, and an outer vehicle panel on the outer vehicle side of the frame.

Disclosure of Invention

Problems to be solved by the invention

However, in the door described above, the edge frames of the frame constituting the door are connected to each other by welding. When welding is used, deformation due to welding occurs, and correction is required to meet required accuracy, which requires labor. The present invention is not limited to door leaves, and the same problem occurs in any product that requires members to be connected to each other.

The present invention has been made in view of such circumstances, and an object thereof is to provide a door leaf for a railway vehicle, a fastening structure, and a method for manufacturing the door leaf for a railway vehicle, which are easy to manufacture.

Means for solving the problems

A door leaf for a railway vehicle that solves the above-described problems is a door leaf for a railway vehicle that includes a1 st member and a2 nd member, wherein the door leaf for a railway vehicle includes a tapping screw that screws into an eyelet provided in the 2 nd member while tapping the eyelet to fasten the 1 st member and the 2 nd member, and a wall of the 2 nd member forming the eyelet has a non-contact region that does not come into contact with the tapping screw in a surface orthogonal to an axial direction of the tapping screw.

When fastening the 1 st member and the 2 nd member with a tapping screw, the fastening torque increases during screwing and fastening becomes impossible. Therefore, according to the above configuration, since the non-contact region where tapping is not performed without contact with the tapping screw is present instead of tapping the entire circumference of the pilot hole, the fastening torque at the time of fastening the tapping screw can be reduced, and the 1 st member and the 2 nd member can be fastened using the tapping screw. Thus, the door leaf for the railway vehicle can be easily manufactured.

In the door leaf for a railway vehicle, it is preferable that the non-contact region is a portion located on an outer side of a thread diameter of the tapping screw in a surface orthogonal to an axial direction of the tapping screw.

In the door leaf for a railway vehicle, it is preferable that the wall forming the bottom hole has a contact region that comes into contact with the tapping screw in a surface orthogonal to the axial direction of the tapping screw, and a wall in the circumferential direction of the tapping screw in the wall of the contact region is parallel to a circumference of an imaginary circle centered on the center of the bottom hole and having a diameter equal to a thread diameter of the tapping screw in the surface orthogonal to the axial direction of the tapping screw. .

In the door leaf for a railway vehicle, it is preferable that the wall forming the bottom hole has a contact region that comes into contact with the tapping screw in a surface orthogonal to the axial direction of the tapping screw, and the wall surface of the contact region includes a portion located outside an imaginary circle having a diameter equal to a thread root diameter of the tapping screw with a center of the bottom hole as a center, in the surface orthogonal to the axial direction of the tapping screw.

In the door leaf for a railway vehicle, it is preferable that the wall forming the bottom hole is provided point-symmetrically with respect to a center axis of the bottom hole.

In the door leaf for a railway vehicle, it is preferable that the non-contact region is provided on 20% to 80% of a circumference of a thread diameter of the tapping screw in a surface orthogonal to an axial direction of the tapping screw.

In the door leaf for a railway vehicle, it is preferable that a volume not to be tapped out of a volume sandwiched between the thread diameter and the thread root diameter of the tapping screw is 20% to 80%.

In the door leaf for a railway vehicle described above, it is preferable that the wall forming the bottom hole includes a1 st contact region that comes into contact with the tapping screw and a1 st non-contact region that does not come into contact with the tapping screw in a1 st position among surfaces orthogonal to the axial direction of the tapping screw, a2 nd contact region that comes into contact with the tapping screw and a2 nd non-contact region that does not come into contact with the tapping screw in surfaces orthogonal to the axial direction of the tapping screw, at a2 nd position that is located closer to a tip end side of the tapping screw than the 1 st position in the axial direction of the tapping screw, the ratio of the 1 st non-contact area to the sum of the 1 st contact area and the 1 st non-contact area is higher than the ratio of the 2 nd non-contact area to the sum of the 2 nd contact area and the 2 nd non-contact area.

In the door leaf for a railway vehicle, it is preferable that the noncontact region is provided in a partial region in an axial direction of the tapping screw.

In the door leaf for a railway vehicle, it is preferable that a receiving portion for receiving chips generated when the tapping screw is tapped is further provided in the noncontact region.

In the door leaf for a railway vehicle, it is preferable that the 2 nd member having the bottom hole is manufactured by extrusion molding.

In the door leaf for a railway vehicle, it is preferable that one of the 1 st member and the 2 nd member is a frame body as a vertical frame, and the other of the 1 st member and the 2 nd member is a frame body as a horizontal frame.

In the door leaf for a railway vehicle, preferably, the 1 st member is a vertical frame, and the 2 nd member is a horizontal frame.

A fastening structure for solving the above-described problems is a fastening structure between a1 st member and a2 nd member, wherein the fastening structure includes a tapping screw that screws in a pilot hole provided in the 2 nd member while tapping the pilot hole, to fasten the 1 st member and the 2 nd member, and a wall of the 2 nd member forming the pilot hole has a non-contact region that does not come into contact with the tapping screw in a surface orthogonal to an axial direction of the tapping screw.

When fastening the 1 st member and the 2 nd member with a tapping screw, the fastening torque increases during screwing and fastening becomes impossible. Therefore, according to the above configuration, since the non-contact region where tapping is not performed without contact with the tapping screw is present instead of tapping the entire circumference of the pilot hole, the fastening torque at the time of fastening the tapping screw can be reduced, and the 1 st member and the 2 nd member can be fastened using the tapping screw. Thus, the manufacturing can be easily performed.

A method of manufacturing a door leaf for a railway vehicle that solves the above-described problems is a method of manufacturing a door leaf for a railway vehicle that includes a1 st member and a2 nd member, wherein a wall that forms an under-hole provided to the 2 nd member has a non-contact region that does not come into contact with a tapping screw screwed into the under-hole in a surface orthogonal to an axial direction of the tapping screw, and the 1 st member and the 2 nd member are fastened by screwing the tapping screw while tapping the under-hole of the 2 nd member.

When the 1 st member and the 2 nd member are to be fastened by using the tapping screw, the fastening torque increases during screwing and fastening becomes impossible. Therefore, according to the above method, since not the entire circumference of the pilot hole is tapped but a non-contact region which is not tapped because it is not in contact with the tapping screw exists, the fastening torque at the time of fastening the tapping screw can be reduced, and the 1 st member and the 2 nd member can be fastened using the tapping screw. Thus, the manufacturing can be easily performed.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to provide a door leaf for a railway vehicle, a fastening structure, and a method of manufacturing a door leaf for a railway vehicle, which are easy to manufacture.

Drawings

Fig. 1 (a) and (b) are views showing a schematic configuration of a door leaf for a railway vehicle according to embodiment 1, in which fig. 1 (a) is a front view and fig. 1 (b) is a side view.

Fig. 2 is an enlarged plan view showing a fastening structure of the door leaf for the railway vehicle according to embodiment 1.

Fig. 3 is an enlarged side view showing the structure of a lateral frame of the door leaf for a railway vehicle according to embodiment 1.

Fig. 4 is a view showing a tapping screw used for the door leaf for the railway vehicle according to embodiment 1.

Fig. 5 is a view showing a bottom hole provided to a lateral frame of the door leaf for the railway vehicle according to embodiment 1.

Fig. 6 is a view showing a state in which a tapping screw is fastened to a bottom hole provided in a lateral frame of the door leaf for a railway vehicle according to embodiment 1.

Fig. 7 is a view showing a bottom hole of embodiment 2.

Fig. 8 is a view showing a state in which a tapping screw is fastened to the bottom hole of embodiment 2.

Fig. 9 is a view showing a bottom hole of embodiment 3.

Fig. 10 is a view showing a state in which a tapping screw is fastened to a bottom hole of embodiment 3.

Fig. 11 is a view showing a bottom hole of embodiment 4.

Fig. 12 is a view showing a state in which a tapping screw is fastened to a bottom hole of embodiment 4.

Fig. 13 is a view showing a bottom hole of embodiment 5.

Fig. 14 is a view showing a state in which a tapping screw is fastened to the bottom hole of embodiment 5.

Description of the reference numerals

A1, contact area; a2, non-contact area; DA. Thread diameter; DB. Thread root diameter; l, thread length; 10. a door leaf; 11. a door tail; 12. a door head; 13. a surface plate; 20. a frame body; 21. a vertical frame as a1 st member; 21A, 1 st through hole; 21B, 2 nd through hole; 22. a horizontal frame as a2 nd member; 22A, 1 st space; 22B, space 2; 22C, space 3; 30. a bottom hole; 31. tapping the wall; 31A, a side surface; 32. a non-threaded wall; 33. a housing part; 40. a self-tapping screw; 41. a screw head; 42. a threaded portion; 50. a bottom hole; 51. tapping the wall; 51A, a side surface; 52. a non-threaded wall; 53. a housing part; 60. a bottom hole; 61. tapping the wall; 62. a non-threaded wall; 63. a housing part; 70. a bottom hole; 71. tapping the wall; 72. a non-threaded wall; 73. a housing part; 80. a bottom hole; 81. tapping the wall; 82. a non-threaded wall; 83. a housing part.

Detailed Description

(embodiment 1)

Hereinafter, a door leaf for a railway vehicle according to embodiment 1 will be described with reference to fig. 1 (a) and (b) to fig. 6. The door leaf is used for a sliding door of a railway vehicle.

(door leaf)

As shown in fig. 1 (a), the left side of the door 10 is a door tail 11, and the right side of the door 10 is a door head 12. The structure of the door 10 on the door tail 11 side is the same as that on the door head 12 side. As shown in fig. 1 (b), a lower portion of the vertical cross section of the door 10 in the vertical direction is curved toward the inside of the railway vehicle.

The door 10 includes a frame 20 and a surface plate 13 serving as a decorative plate or a base joined to each surface of the frame 20. The frame body 20 includes: a vertical frame 21 as a1 st member; and a horizontal frame 22 as a2 nd member connected to the vertical frame 21 in a state of being orthogonal to the vertical frame 21. The vertical frame 21 is a part of the frame body extending in the vertical direction of the door 10. The horizontal frame 22 is a part of the frame body extending in the left-right direction of the door 10. The frame body 20 is formed into a quadrangular frame by two vertical frames 21 and two horizontal frames 22.

As shown in fig. 2, the surface plate 13 is attached to the lower side in the drawing and the upper side in the drawing as the front surface side of the frame body 20 with an adhesive. That is, the frame 20 is sandwiched by the two surface plates 13 from both sides.

(frame body)

As shown in fig. 2, the vertical frame 21 is an aluminum extruded material of a rectangular cylinder, and is manufactured by extrusion molding. The lateral frame 22 is a quadrangular aluminum extruded section, and is manufactured by extrusion molding.

The vertical frame 21 and the horizontal frame 22 are fastened by tapping screws 40. The tapping screws 40 penetrate the vertical frame 21 and screw into the bottom holes 30 provided in the horizontal frame 22 while tapping the bottom holes 30, thereby fastening the vertical frame 21 and the horizontal frame 22. The vertical frame 21 is provided with a1 st through hole 21A through which a screw head 41 of the tapping screw 40 is inserted and a2 nd through hole 21B through which a screw portion 42 of the tapping screw 40 is inserted. The 2 nd through hole 21B is sized so that the head 41 of the tapping screw 40 does not penetrate therethrough. The tapping screw 40 penetrates the 1 st through hole 21A, and only the screw portion 42 penetrates the 2 nd through hole 21B. The vertical frame 21 is sandwiched and fastened between the screw head 41 of the tapping screw 40 and the horizontal frame 22. That is, the vertical frame 21 and the horizontal frame 22 are fastened by the fastening structure of the tapping screws 40 and the bottom holes 30.

As shown in fig. 3, the horizontal frame 22 is a member having a1 st space 22A, a2 nd space 22B, and a 3 rd space 22C. A pilot hole 30 into which a tapping screw 40 is screwed is provided between the 1 st space 22A and the 2 nd space 22B of the lateral frame 22. The bottom hole 30 is formed by extrusion molding and therefore penetrates the lateral frame 22.

As shown in fig. 4, the tapping screw 40 includes a screw head 41 and a screw portion 42. The screw head 41 is of a blunt head type. The tapping screw 40 is 2 types of tapping screws in which the tip of the threaded portion 42 is cut and the thread pitch is large. The length of the threaded portion 42 is the thread length L. The bottom hole 30 penetrates the lateral frame 22, and therefore, the axial length of the bottom hole 30 is longer than the screw length L. The diameter of the threaded portion 42 including the thread is a thread diameter DA, and the diameter of the root of the threaded portion 42 is a thread root diameter DB.

As shown in fig. 5, the wall of the lateral frame 22 forming the bottomed hole 30 includes, in a face orthogonal to the axial direction of the tapping screw 40, a contact region a1 that is in contact with the tapping screw 40 and a non-contact region a2 that is not in contact with the tapping screw 40. The contact region a1 is a portion where the wall forming the pilot hole 30 in the surface orthogonal to the axial direction of the tapping screw 40 is located inward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. The non-contact region a2 is a portion where the wall forming the pilot hole 30 in the surface orthogonal to the axial direction of the tapping screw 40 is located outward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. Of the walls forming the bottomed hole 30, the wall located at the contact region a1 is set as the tapping wall 31, and the wall located at the non-contact region a2 is set as the non-tapping wall 32. Bottom hole 30 is provided over the entire length of lateral frame 22.

Desirably, the non-contact region a2 of the pilot hole 30 is provided in the range of 20% to 80% of the circumference of the thread diameter DA of the tapping screw 40 in the plane orthogonal to the axial direction of the tapping screw 40. In this case, the tapping screw 40 can be screwed well without excessively increasing the torque required for fastening. Further, the tapped area is not too small, and a sufficient fastening force can be obtained. In the present embodiment, the non-contact region a2 is provided at about 50% of the circumference of the thread diameter DA of the tapping screw 40.

It is desirable that the volume that is not tapped in the volume sandwiched between the thread diameter DA and the thread root diameter DB of the tapping screw 40 be 20% to 80%. In this case, the tapping screw 40 can be screwed well without excessively increasing the torque required for fastening. Further, the tapped area is not too small, and a sufficient fastening force can be obtained. In the present embodiment, the volume that will not be tapped is about 50%.

The walls forming the bottomed hole 30 are disposed point-symmetrically with the center axis of the bottomed hole 30 as the center. That is, the tapping wall 31 and the non-tapping wall 32 are disposed at point-symmetrical positions. The tapped walls 31 and the non-tapped walls 32 are alternately provided with 4 each.

The wall surface of the tap wall 31 of the contact region a1 includes a portion located outward of an imaginary circle having a diameter equal to the thread root diameter DB of the tapping screw 40 with the center of the pilot hole 30 as the center, in a plane orthogonal to the axial direction of the tapping screw 40. In addition, the wall surface is the interface between the bottom hole 30 and the lateral frame 22. Specifically, the wall surface of the tapping wall 31 is a straight line in a plane orthogonal to the axial direction of the tapping screw 40, and the circumferential center thereof is aligned with the thread root diameter DB and approaches a virtual circle having the thread diameter DA as a diameter as it goes away from the center. That is, when the tapping screw 40 is screwed into the bottom hole 30, the fastening torque at the center portion of the tap wall 31 becomes maximum. When the tapping screw 40 is gradually screwed into the bottom hole 30, the contact area between the tapping screw 40 and the tapping wall 31 gradually increases, and the fastening torque gradually increases. Thus, the fastening torque can be reduced as compared with the case where the tapping screw 40 is uniformly in contact with the tapping wall.

The non-tapping wall 32 of the non-contact region a2 is a curve parallel to the circumference of an imaginary circle centered on the center of the pilot hole 30 and having the thread diameter DA of the tapping screw 40 as a diameter in a plane orthogonal to the axial direction of the tapping screw 40.

The non-contact region a2 is provided with a receiving portion 33 for receiving chips generated when the tapping screw 40 is tapped. The receiving portion 33 is a portion that is located outside the thread diameter DA of the tapping screw 40 and is surrounded by the non-tapping wall 32 and the side surface 31A of the tapping wall 31.

(production method)

Next, a method for manufacturing the door 10 will be described.

First, as shown in fig. 2, horizontal frame 22 and vertical frame 21 are brought into contact with each other by aligning the position of 2 nd through hole 21B of vertical frame 21 with the position of bottom hole 30 of horizontal frame 22.

Next, the tapping screw 40 is inserted through the 1 st through-hole 21A, the tapping screw 40 is inserted through the 2 nd through-hole 21B, and the tapping screw 40 is screwed in by rotating the tapping screw 40 with a tool.

As shown in fig. 6, the tapping screw 40 is screwed while tapping the contact area a1 of the pilot hole 30. That is, the tapping wall 31 of the bottom hole 30 between the thread diameter DA and the thread root diameter DB is tapped. The dotted portion of the tapping wall 31 is tapped. The upper right half of the drawing shows the thread of the tapping screw 40 visible above the tapping wall 31 in the axial direction of the tapping screw 40. At this time, the non-contact region a2 of the pilot hole 30 does not touch the tapping screw 40 and is not tapped. The chips generated by the tapping screw 40 are contained in the receiving portion 33 of the bottom hole 30 and in the deep portion of the bottom hole 30.

Here, when the tapped wall is located at the entire circumference between the thread diameter DA and the thread root diameter DB of the bottom hole 30, the fastening torque increases, and fastening cannot be performed during screwing. Therefore, by providing the non-contact region a2 in the pilot hole 30, the area to be tapped in the surface perpendicular to the axial direction of the tapping screw 40 is reduced, and the fastening torque can be reduced. In addition, the tapped width of the tapping wall 31 is gradually increased and gradually decreased from the center, the fastening torque is maximum at the center of the tapping wall 31, and the fastening torque can be reduced for the tapping wall 31.

Next, as shown in fig. 2, two surface plates 13 sandwich two vertical frames 21 and two horizontal frames 22 from both sides to fasten a frame 20. The adhesive is applied to the surface of the frame 20 to bond the surface plate 13 to the surface of the frame 20. Therefore, the frame 20 can be easily manufactured without using a connection by welding. In particular, since the door 10 with a bent lower portion is corrected by a change in bending when welded, a fastening structure using the tapping screw 40 is useful.

Next, the effects of embodiment 1 will be described.

(1) Since the non-contact region a2 is not tapped over the entire circumference of the bottom hole 30 but is not tapped by contact with the tapping screw 40, the fastening torque at the time of fastening the tapping screw 40 can be reduced, and the vertical frame 21 and the horizontal frame 22 can be fastened using the tapping screw 40. Therefore, the door 10 for a railway vehicle can be easily manufactured without using welding which requires labor.

(2) By providing the non-tapping wall 32 for forming the pilot hole 30 at a position outside the thread diameter DA of the tapping screw 40, the non-contact region a2 that is not tapped because of non-contact when the tapping screw 40 is fastened can be provided.

(3) The fastening torque of the tapping screw 40 at the time of tapping can be reduced as compared with a case where the wall surface of the tapping wall 31 of the contact region a1 does not include a portion located outside a virtual circle having the thread root diameter DB of the tapping screw 40 as a diameter, that is, a case where all of the contact regions a1 are located inside a virtual circle having the thread root diameter DB as a diameter.

(4) Since the tapping screw 40 is hit at a point-symmetric position when the tapping screw 40 is fastened, the tapping screw 40 can be easily positioned, and the tapping screw 40 can be stably fastened.

(5) Fastening torque at the time of fastening the tapping screw 40 can be reduced, and the vertical frame 21 and the horizontal frame 22 can be fastened using the tapping screw 40.

(6) Since the chips are accommodated in the accommodating portion 33, the chips can be prevented from being caught between the tapping screw 40 and the contact region a1, and an increase in fastening torque can be prevented.

(7) Since the bottom hole 30 is formed by extrusion molding together with the lateral frame 22, even a complicated shape such as the bottom hole 30 can be molded. In addition, the bottom hole 30 does not need to be additionally formed.

(embodiment 2)

Hereinafter, a door panel for a railway vehicle according to embodiment 2 will be described with reference to fig. 7 and 8. The shape of the bottom hole of the door leaf for a railway vehicle of this embodiment is different from that of the bottom hole of the above-described embodiment 1. The following description focuses on differences from embodiment 1.

As shown in fig. 7 and 8, the lateral frame 22 is provided with a bottom hole 50 into which the tapping screw 40 is screwed. The wall forming the bottomed hole 50 includes, in a face orthogonal to the axial direction of the tapping screw 40, a contact region a1 that will be tapped by the tapping screw 40 and a non-contact region a2 that the tapping screw 40 will not encounter and will not be tapped. The contact region a1 is a portion where the wall forming the pilot hole 50 in the surface orthogonal to the axial direction of the tapping screw 40 is located inward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. The non-contact region a2 is a portion where the wall forming the pilot hole 50 in the surface orthogonal to the axial direction of the tapping screw 40 is located outward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. Of the walls forming the bottomed hole 50, the wall located at the contact region a1 is set as a tapped wall 51, and the wall located at the non-contact region a2 is set as a non-tapped wall 52.

The non-contact region a2 is provided at approximately 30% of the circumference of the thread diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In addition, the volume that is not tapped out of the volume sandwiched by the thread diameter DA and the thread root diameter DB of the tapping screw 40 is set to account for approximately 30%.

The walls forming the bottomed hole 50 are disposed point-symmetrically with the center axis of the bottomed hole 50 as the center. That is, the tapping wall 51 and the non-tapping wall 52 are disposed at point-symmetrical positions. The tapped walls 51 and the non-tapped walls 52 are alternately provided with 4 each.

The tapping wall 51 of the contact region a1 is parallel to the circumference of an imaginary circle centered on the center of the pilot hole 50 and having a diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In detail, the tapping wall 51 is curved in a plane orthogonal to the axial direction of the tapping screw 40 and aligned with the thread root diameter DB. That is, when the tapping screw 40 is screwed into the pilot hole 50, the same fastening torque is applied to any position of the tap wall 51. As shown in fig. 8, the spot-delineated portion of the tapping wall 51 is a tapped portion, and is a portion where the tapping screw 40 is engaged with the tapping wall 51. The upper right half of the drawing shows the thread of the tapping screw 40 visible above the tapping wall 51 in the axial direction of the tapping screw 40.

The non-tapping wall 52 of the non-contact region a2 is a curve parallel to the circumference of an imaginary circle centered on the center of the pilot hole 50 and having the thread diameter DA of the tapping screw 40 as a diameter in a plane orthogonal to the axial direction of the tapping screw 40.

The non-contact region a2 is provided with a receiving portion 53 for receiving chips generated when the tapping screw 40 is tapped. The receiving portion 53 is a portion that is located outside the thread diameter DA of the tapping screw 40 and is surrounded by the side surface 51A of the tapping wall 51 and the non-tapping wall 52.

As described above, by providing the non-contact region a2 in the pilot hole 50, the area to be tapped in the surface perpendicular to the axial direction of the tapping screw 40 is reduced, and therefore, the fastening torque can be reduced. In addition, since the tapping wall 51 has the same width to be tapped, the fastening torque does not change at the tapping wall 51, and the fastening torque can be stabilized.

Next, the effect of embodiment 2 will be described. Among these, the following effects are obtained in addition to the effects (1), (2), (4) and (7) of embodiment 1.

(8) Since the distance between the contact region a1 and the tapping screw 40 is constant, the tapping screw 40 can be easily positioned, and the tapping screw 40 can be stably fastened.

(embodiment 3)

Hereinafter, embodiment 3 of the door leaf for a railway vehicle will be described with reference to fig. 9 and 10. The shape of the bottom hole of the door leaf for a railway vehicle of this embodiment is different from that of the bottom hole of the above-described embodiment 1. The following description focuses on differences from embodiment 1.

As shown in fig. 9 and 10, the lateral frame 22 is provided with a bottom hole 60 into which the tapping screw 40 is screwed. The wall forming the pilot hole 60 includes, in a face orthogonal to the axial direction of the tapping screw 40, a contact region a1 that is to be tapped by the tapping screw 40 and a non-contact region a2 that the tapping screw 40 does not touch and is not to be tapped. The contact region a1 is a portion where the wall forming the pilot hole 60 in the surface orthogonal to the axial direction of the tapping screw 40 is located inward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. The non-contact region a2 is a portion where the wall forming the pilot hole 60 in the surface orthogonal to the axial direction of the tapping screw 40 is located outward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. Of the walls forming the bottomed hole 60, the wall located at the contact region a1 is set as a tapped wall 61, and the wall located at the non-contact region a2 is set as a non-tapped wall 62.

The non-contact region a2 is provided at approximately 50% of the circumference of the thread diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In addition, the volume that is not tapped out of the volume sandwiched by the thread diameter DA and the thread root diameter DB of the tapping screw 40 is set to account for approximately 50%.

The walls forming the bottomed hole 60 are disposed point-symmetrically with the center axis of the bottomed hole 60 as the center. That is, the tapping wall 61 and the non-tapping wall 62 are disposed at point-symmetrical positions. The tapped walls 61 and the non-tapped walls 62 are alternately provided with 4 each.

The tapping wall 61 of the contact region a1 is parallel to the circumference of an imaginary circle centered on the center of the pilot hole 60 and having the diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In detail, the tapping wall 61 is curved in a plane orthogonal to the axial direction of the tapping screw 40 and aligned with the thread root diameter DB. That is, the same fastening torque is applied to any position of the tapping wall 61 when the tapping screw 40 is screwed into the bottom hole 60. As shown in fig. 10, the spot-delineated portion of the tapping wall 61 is a tapped portion, and is a portion where the tapping screw 40 is engaged with the tapping wall 61. The right half of the upper side in the drawing is in a state where the thread of the tapping screw 40 is visible at a position above the tapping wall 61 in the axial direction of the tapping screw 40.

The non-tapping wall 62 of the non-contact region a2 is formed in an arc shape centered on a point different from the shaft of the tapping screw 40 in a plane perpendicular to the axial direction of the tapping screw 40.

The non-contact region a2 is provided with a receiving portion 63 for receiving chips generated when the tapping screw 40 is tapped. The receiving portion 63 is a portion surrounded by the non-tapping wall 62 outside the thread diameter DA of the tapping screw 40.

As described above, by providing the non-contact region a2 in the pilot hole 60, the area to be tapped in the surface perpendicular to the axial direction of the tapping screw 40 is reduced, and therefore, the fastening torque can be reduced. Further, since the tapping wall 61 has the same width to be tapped, the fastening torque does not change at the tapping wall 61, and the fastening torque can be stabilized. According to the configuration of embodiment 3, the effects (1), (2), (4) to (7) of embodiment 1 and (8) of embodiment 2 are obtained.

(embodiment 4)

Hereinafter, a door leaf for a railway vehicle according to embodiment 4 will be described with reference to fig. 11 and 12. The shape of the bottom hole of the door leaf for a railway vehicle of this embodiment is different from that of the bottom hole of the above-described embodiment 1. The following description focuses on differences from embodiment 1.

As shown in fig. 11 and 12, the lateral frame 22 is provided with a bottom hole 70 into which the tapping screw 40 is screwed. The wall forming the pilot hole 70 includes, in a face orthogonal to the axial direction of the tapping screw 40, a contact region a1 that is to be tapped by the tapping screw 40 and a non-contact region a2 that the tapping screw 40 does not touch and is not to be tapped. The contact region a1 is a portion where the wall forming the pilot hole 70 in the surface orthogonal to the axial direction of the tapping screw 40 is located inward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. The non-contact region a2 is a portion where the wall forming the pilot hole 70 in the surface orthogonal to the axial direction of the tapping screw 40 is located outward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. Of the walls forming the bottomed hole 70, the wall located at the contact region a1 is set as a tapped wall 71, and the wall located at the non-contact region a2 is set as a non-tapped wall 72.

The non-contact region a2 is provided in a plane orthogonal to the axial direction of the tapping screw 40 at approximately 60% of the circumference of the thread diameter DA of the tapping screw 40. In addition, the volume that is not tapped out of the volume sandwiched by the thread diameter DA and the thread root diameter DB of the tapping screw 40 is set to account for approximately 60%.

The walls forming the bottomed hole 70 are disposed point-symmetrically with the center axis of the bottomed hole 70 as the center. That is, the tapping wall 71 and the non-tapping wall 72 are disposed at point-symmetrical positions. The tapped walls 71 and the non-tapped walls 72 are alternately provided with 4 each.

The wall surface of the tap wall 71 of the contact region a1 includes a portion located outward of an imaginary circle having a diameter equal to the thread root diameter DB of the tapping screw 40 with the center of the pilot hole 70 as the center, in a plane orthogonal to the axial direction of the tapping screw 40. Wherein the wall is the interface between the bottom aperture 70 and the transverse frame 22. Specifically, the wall surface of the tapping wall 71 is curved in a plane orthogonal to the axial direction of the tapping screw 40, and the circumferential center thereof is aligned with the thread root diameter DB and approaches a virtual circle having the thread diameter DA as a diameter as it goes away from the center. That is, when the tapping screw 40 is screwed into the pilot hole 70, the fastening torque is maximized at the center portion of the tap wall 71. When the tapping screw 40 is gradually screwed into the pilot hole 70, the contact area between the tapping screw 40 and the tap wall 71 gradually increases, and the fastening torque increases. As shown in fig. 12, the spot-delineated portion of the tapping wall 71 is a tapped portion, and is a portion where the tapping screw 40 is engaged with the tapping wall 71. The right half of the upper side in the drawing is in a state where the thread of the tapping screw 40 is visible at a position above the tapping wall 71 in the axial direction of the tapping screw 40. Therefore, the fastening torque can be reduced compared to the case where the tapping screw 40 uniformly contacts the tap walls 51, 61 as in embodiment 2 and embodiment 3.

The non-tapping wall 72 of the non-contact region a2 includes a portion that is located outside the thread diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In detail, the non-tapping wall 72 is constituted by a straight line and a curved line connecting the tapping wall 71 in a plane orthogonal to the axial direction of the tapping screw 40.

The non-contact region a2 is provided with a receiving portion 73 for receiving chips generated when the tapping screw 40 is tapped. The receiving portion 73 is a portion surrounded by the non-tapping wall 72 outside the thread diameter DA of the tapping screw 40.

As described above, by providing the non-contact region a2 in the pilot hole 70, the area to be tapped in the surface perpendicular to the axial direction of the tapping screw 40 is reduced, and therefore, the fastening torque can be reduced. In addition, since the width of the tapping wall 71 to be tapped is gradually increased and gradually decreased from the center, the fastening torque is maximized at the center of the tapping wall 71, and the fastening torque can be reduced for the tapping wall 71. With the configuration of embodiment 4, the effects (1) to (7) of embodiment 1 are obtained.

(embodiment 5)

Hereinafter, a door panel for a railway vehicle according to embodiment 5 will be described with reference to fig. 13 and 14. The shape of the bottom hole of the door leaf for a railway vehicle of this embodiment is different from that of the bottom hole of the above-described embodiment 1. The following description focuses on differences from embodiment 1.

As shown in fig. 13 and 14, the lateral frame 22 is provided with a bottom hole 80 into which the tapping screw 40 is screwed. The wall forming the pilot hole 80 includes, in a face orthogonal to the axial direction of the tapping screw 40, a contact region a1 that is to be tapped by the tapping screw 40 and a non-contact region a2 that the tapping screw 40 does not touch and is not to be tapped. The contact region a1 is a portion where the wall forming the pilot hole 80 in the surface orthogonal to the axial direction of the tapping screw 40 is located inward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. The non-contact region a2 is a portion where the wall forming the pilot hole 80 in the surface orthogonal to the axial direction of the tapping screw 40 is located outward of the thread diameter DA of the tapping screw 40 indicated by the two-dot chain line. Of the walls forming the bottomed hole 80, the wall located at the contact region a1 is set as a tapped wall 81, and the wall located at the non-contact region a2 is set as a non-tapped wall 82.

The non-contact region a2 is provided in a plane orthogonal to the axial direction of the tapping screw 40 at approximately 60% of the circumference of the thread diameter DA of the tapping screw 40. In addition, the untapped volume in the volume sandwiched by the thread diameter DA and the thread root diameter DB of the tapping screw 40 is set to account for about 60%.

The walls forming the bottomed hole 80 are disposed point-symmetrically with the center axis of the bottomed hole 80 as the center. That is, the tapping wall 81 and the non-tapping wall 82 are disposed at point-symmetrical positions. The tapped walls 81 and the non-tapped walls 82 are alternately provided with 4 each.

The wall surface of the tap wall 81 in the contact region a1 includes a portion located outside an imaginary circle having a diameter equal to the thread root diameter DB of the tapping screw 40 with the center of the pilot hole 80 as the center, in a plane orthogonal to the axial direction of the tapping screw 40. In addition, the wall surface is the interface between bottom hole 80 and transverse frame 22. Specifically, the tapping wall 81 is linear in a plane orthogonal to the axial direction of the tapping screw 40, and the center thereof is aligned with the thread root diameter DB and approaches a virtual circle having the thread diameter DA as a diameter as it goes away from the center. That is, when the tapping screw 40 is screwed into the pilot hole 80, the fastening torque is maximized at the center of the tap wall 81. When the tapping screw 40 is gradually screwed into the pilot hole 80, the contact area between the tapping screw 40 and the tap wall 81 gradually increases, and the fastening torque increases. As shown in fig. 14, the spot-delineated portion of the tapping wall 81 is a tapped portion, and is a portion where the tapping screw 40 is engaged with the tapping wall 81. The right half of the upper side in the drawing is in a state where the thread of the tapping screw 40 is visible at a position located above the tapping wall 81 in the axial direction of the tapping screw 40. Therefore, the fastening torque can be reduced compared to the case where the tapping screw 40 uniformly contacts the tap walls 51, 61 as in embodiment 2 and embodiment 3.

The non-tapping wall 82 of the non-contact region a2 includes a portion that is located outside the thread diameter DA of the tapping screw 40 in a plane orthogonal to the axial direction of the tapping screw 40. In detail, the non-tapping wall 82 is formed of a straight line continuous with the tapping wall 81 and a curved line connecting the two straight lines in a plane orthogonal to the axial direction of the tapping screw 40.

The non-contact region a2 is provided with a receiving portion 83 for receiving chips generated when the tapping screw 40 is tapped. The receiving portion 83 is a portion surrounded by the non-threaded wall 82 on the outer side of the thread diameter DA of the tapping screw 40.

As described above, by providing the non-contact region a2 in the pilot hole 80, the area to be tapped in the surface perpendicular to the axial direction of the tapping screw 40 is reduced, and therefore, the fastening torque can be reduced. In addition, since the tapped width of the tapping wall 81 is gradually increased and gradually decreased from the center, the fastening torque is maximized at the center of the tapping wall 81, and the fastening torque can be reduced for the tapping wall 81.

Next, the effect of embodiment 5 will be described. Among them, the effects of (1) to (7) of embodiment 1 are obtained, and the following effects are obtained.

(9) Since the pilot hole 80 is formed by a straight line in which the tapped wall 81 and the non-tapped wall 82 are continuous, the shape of the pilot hole 80 is not complicated, and the extrusion of the transverse frame 22 can be easily performed compared to a complicated shape.

(other embodiments)

The above embodiments can be modified and implemented as follows. The above embodiments and the following modifications can be combined and implemented within a range not technically contradictory to each other.

In each of the above embodiments, the bottom holes 30, 50, 60, 70, 80 are provided over the entire length of the lateral frame 22. However, the shape of the bottom hole may be different over the entire length of the lateral frame 22. The tapping screw 40 is provided with a1 st position located on the screw head 41 side and a2 nd position located on the tip side in the axial direction. The wall forming the pilot hole includes a1 st contact region in contact with the tapping screw 40 and a1 st non-contact region not in contact with the tapping screw 40 in a surface orthogonal to the axial direction of the tapping screw 40 at a1 st position, and includes a2 nd contact region in contact with the tapping screw 40 and a2 nd non-contact region not in contact with the tapping screw 40 in a surface orthogonal to the axial direction of the tapping screw 40 at a2 nd position located closer to the tip end side of the tapping screw 40 than the 1 st position in the axial direction of the tapping screw 40. Further, the ratio of the 1 st non-contact region to the sum of the 1 st contact region and the 1 st non-contact region may be higher than the ratio of the 2 nd non-contact region to the sum of the 2 nd contact region and the 2 nd non-contact region. For example, the bottom hole 30 of the embodiment 1 may be formed at the 1 st position on the screw head 41 side at a ratio of 50%, and the bottom hole 50 of the embodiment 2 may be formed at the 2 nd position on the tip side at a ratio of 30%. Alternatively, the axial offset of the pilot hole with respect to the tapping screw 40 may be used. In this case, the fastening torque on the side close to the screw head 41 can be weakened, and the fastening strength on the tip side can be improved.

The noncontact region a2 may be provided in a partial region in the axial direction of the tapping screw 40. For example, the depth of the pilot hole 30, 50, 60, 70, 80 may be set to be shorter than the thread length L of the tapping screw 40.

In each of the above embodiments, the non-contact region a2 is defined as a portion in which the wall forming the pilot hole 30, 50, 60, 70, 80 is located outward of the thread diameter DA of the tapping screw 40, as indicated by the two-dot chain line, in the surface perpendicular to the axial direction of the tapping screw 40. However, the noncontacting region a2 may be a portion where the wall of the pilot hole 30, 50, 60, 70, 80 is formed at the position of the thread diameter DA indicated by the two-dot chain line of the tapping screw 40 in the plane orthogonal to the axial direction of the tapping screw 40. In this case, the housing portion is not provided.

In each of the above embodiments, the walls forming the bottomed holes 30, 50, 60, 70, 80 are provided in point symmetry about the center axes of the bottomed holes 30, 50, 60, 70, 80, and the walls forming the bottomed holes may not be provided in point symmetry.

In each of the above embodiments, the bottom holes 30, 50, 60, 70, and 80 are formed in the horizontal frame 22 by extrusion molding, but the bottom holes may be formed in the horizontal frame 22 by cutting or the like.

The length of the pilot hole may be a part of the entire length of the lateral frame as long as the pilot hole has a thread length L from the opening to the tapping screw.

In each of the above embodiments, the 1 st space 22A, the 2 nd space 22B, and the 3 rd space 22C are provided in the lateral frame 22, but a space may be arbitrarily provided in the lateral frame 22, or a space may not be provided in the lateral frame 22.

In the above embodiment, 2 types of tapping screws are used, but the number is not limited to 2, and 1 type of tapping screw having a sharp tip and a thread pitch thicker than that of the 2 types of tapping screws, 3 types of tapping screws having a sharp tip and a thread pitch thinner than that of the 2 types of tapping screws, and 4 types of tapping screws having a sharp tip and a thread pitch equal to that of the 2 types of tapping screws may be used. Further, the screw may have a grooved shape having a groove at the tip of the screw. Further, a tapping screw having a threaded portion with a triangular cross section may be used.

In the above embodiment, the screw head 41 of the tapping screw 40 is formed in a flat round head shape, but the screw head of the tapping screw may be formed in other shapes such as a countersunk shape, a half countersunk shape, and a half round head shape.

In each of the above embodiments, the size of the pilot hole may be arbitrarily changed in accordance with the thread diameter DA and the thread root diameter DB of the tapping screw 40.

In each of the above embodiments, the horizontal frame 22 as the 2 nd member is provided with the bottom holes 30, 50, 60, 70, and 80, and the vertical frame 21 as the 1 st member is provided with the 2 nd through hole 21B. However, the horizontal frame as the 1 st member may be provided with a through hole, and the vertical frame as the 2 nd member may be provided with a bottom hole, and the horizontal frame may be fastened to the vertical frame with a tapping screw.

In each of the above embodiments, the lower portion of the door 10 in the vertical direction is curved toward the inside of the railway vehicle, but the lower portion of the door in the vertical direction may be a straight portion that is not curved.

In the above embodiments, the tapping screw and the bottom hole are used as the fastening structure of the frame body 20 of the door 10 for the railway vehicle, but the fastening structure is not limited to the frame body of the door for the railway vehicle, and may be used as the fastening structure between two members.

In each of the above embodiments, two members are fastened by a tapping screw and a pilot hole without using welding. However, if welding is used after fastening two members by a tapping screw and a pilot hole, deformation due to welding can be suppressed without requiring correction to meet required accuracy.