JP2000257330A - Door hinge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically keep a door in an opened state. SOLUTION: This door hinge device is provided with a rotary cyinder fixed to a door, a fixed cylinder fixed to a door frame, a plug member 107 fixed to one end of the rotary cylinder, a fixed member 157 irrotationally connected in the fixed cylinder, an actuation member 162 in which a projection part 163 vertically movably arranged between the plug member 107 and the fixed member 157 and engaged with an engaging groove 151 of the plug member 107 is formed, a pin member 170 penetrating the fixed member 157 at one end thereof to come into contact with the actuation member 162, a support member 171 for supporting the other end of the pin member 170, and a third coil spring 174 to urge the actuation member 162 to the direction in which the projection is engaged with the engaging groove 151 of the plug member 109 through the support member 171 and the pin member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door hinge device, and more particularly, to a door hinge device which is provided on a door in a state where no torsional moment acts on a torsion coil spring provided inside the door hinge device, and is subjected to another elastic force adjusting process. By adjusting the torsional moment of the door, the installation work and the elasticity adjustment work can be performed easily and easily, and the door can be automatically kept open to improve the convenience of the door operation. More particularly, the present invention relates to a door hinge device that improves safety by automatically closing a door in an open state when a temperature around the door increases due to a fire.

[0002]

2. Description of the Related Art Generally, door hinges are mounted on doors in almost all buildings, and are used to rotatably support a door on a corresponding door frame. The door hinge includes a pair of vertical support elements arranged parallel to each other in a vertical direction, or a pair of horizontal support elements arranged parallel to each other in a horizontal direction. One of the pair of horizontal or vertical support elements is fixed to the door,
The other support element is fixed to the door frame.

[0003] In the case of a door hinge having such a simple structure, the door is not automatically closed, which causes various inconveniences. Therefore, a hydraulically operated door automatic for automatically closing the door is provided. A closing device is used. However, there is a problem that such a door automatic closing device is expensive and installation is not easy.

In order to solve such a problem, a door hinge device in which a torsion coil spring is provided in each door hinge so that the door is automatically closed has been known in the art by the present applicant and the like. And
Such door hinge devices are relatively inexpensive and have the advantage of being widely used.

However, in the prior art door hinge device, the door hinge device is mounted on the door and the door frame in a state where a predetermined torsional moment is applied by the torsion coil spring. The moment, or elasticity adjustment operation, becomes difficult, so that if the torsional moment is not properly adjusted, the door may close more quickly than expected by the pedestrian. Further, in the prior art door hinge device using a torsion coil spring, there is no means for automatically maintaining the door open at a predetermined position, and therefore, there is a problem that convenience due to operation of the door is reduced. Was. Furthermore, there has been a problem that means for automatically closing a door maintained in an open state in the event of a fire or the like has not been provided.

[0006]

SUMMARY OF THE INVENTION The present invention is provided to solve the problems inherent in the prior art door hinge devices as described above, and a main object of the present invention is to provide a door hinge device provided inside. In the state where no torsional moment acts on the torsion coil spring, after it is provided on the door, the torsional coil spring torsional moment can be adjusted by another elastic force adjustment process,
It is an object of the present invention to provide a door hinge device that enables the installation work and the adjustment work of elastic force to be performed simply, easily and quickly.

[0007] It is another object of the present invention to provide a door hinge device in which the door is automatically maintained in an open state, thereby improving the convenience of door operation.

It is still another object of the present invention to provide a door hinge device which improves safety by automatically closing a door in an open state when a temperature around the door increases due to a fire. It is in.

[0009]

According to one aspect of the present invention, there is provided a door hinge device,
The apparatus comprises: a first support element fixed to a door and having a rotating cylinder; a second support element fixed to a door frame and having a pair of fixed cylinders respectively disposed at both ends of the rotating cylinder; The door automatically returns to the closed position when the external force applied to the door is removed by applying a torsional force to keep the door in the closed position and further increasing the torsional force when the door is opened. And a door open state maintaining means for maintaining an open state of the door at a specific open position of the door.

The door hinge means is connected to a first fixed cylinder of a second support element, and is connected to a plug member fixed to one end of the rotary cylinder, and one end penetrates a second fixed cylinder of the second support element. Inserted into the rotating cylinder, rotatably supported by the plug member, a large-diameter portion is formed at the other end portion, a first concave portion having an open side is formed at the large-diameter portion, A rotary shaft having a second concave portion formed on the bottom surface of the first concave portion, and wound around the rotary shaft inside the rotary cylinder, one end is fixed to the plug member, and the other end is rotated. A torsion coil spring fixed to the large-diameter portion of the shaft, and disposed in the first concave portion of the large-diameter portion of the rotating shaft so as to be able to reciprocate in the radial direction through the opened one side portion. , An open portion having a tapered surface is formed, A claw member formed with a claw that is engaged with any one of a plurality of ratchets of an inward ratchet wheel portion formed on an inner peripheral surface of the constant cylinder; and an inner surface of a large-diameter portion of the rotating shaft having the first recess. The cap member to be fastened, one end portion is located inside the second concave portion, the other end portion penetrates the cap member and protrudes to the outside, and the middle portion is formed on the tapered surface of the open portion of the pawl member. A push rod having a slidable inverted triangular portion formed therein, and the pawl member inside the first concave portion, wherein the pawl is the second
A first coil spring for urging in a direction engaged with the inward ratchet wheel portion of the fixed cylinder; and a second coil spring for urging the push rod toward the cap member inside the second recess. A coil spring.

A cutout portion is formed on the right side of the large-diameter portion of the rotary shaft, and a third recess for accommodating a spring and a ball is formed on the bottom surface of the cutout portion. The locking groove is formed so that the ball housed in the third recess is elastically engaged.

The first and second support elements are a pair of vertical support elements arranged in parallel in the vertical direction.
The large diameter portion has a first enlarged outer diameter portion having substantially the same outer diameter as the inner diameter of the rotating cylinder and a second enlarged outer diameter portion having an outer diameter larger than the inner diameter of the rotating cylinder. An enlarged inner diameter portion having an inner diameter larger than the inner diameter of the rotary cylinder is formed at the other end, so that a step portion is formed on the inner surface of the rotary cylinder, and one end surface of the second enlarged outer diameter portion is formed on the step portion. Is settled down. A flange portion is formed at a portion of the push rod close to the one end, on which one end of the second coil spring is seated.

The plug member has a support shaft extending into the rotary cylinder. A pair of insertion grooves are formed in a free end of the support shaft and one end of the rotary shaft, respectively. Both ends of the rod member are inserted into the insertion grooves, and a pair of balls are interposed between the bottom surfaces of the pair of insertion grooves and both ends of the rod member to guide the rotation of the rotating shaft. And both ends of the rotary cylinder and the first
A pair of ring washers are interposed between the first and second fixed cylinders.

When the pawl of the pawl member is engaged with any one of a number of ratchets formed on the inward ratchet wheel portion of the second fixed cylinder, the rotation shaft can rotate only in one direction and rotate in the other direction. When the rotation shaft is rotated in the one direction by a tool inserted into the tool insertion groove of the cap member, the torsion coil spring receives a force action in a winding direction, and the torsional moment further increases. When the push rod is pushed in while the biasing force of the first and second coil springs is being overcome to retract the pawl member into the first recess,
The engagement between the pawl and the ratchet is released, and the torsion coil spring that has been wound is unwound, thereby reducing the torsional moment.

The one direction is a clockwise direction, the other direction is a counterclockwise direction, and the torsion coil spring is a counterclockwise torsion coil spring wound in a counterclockwise direction. When the torsion coil spring is rotated counterclockwise, the torsion coil spring receives a force in the winding direction, and the torsional moment increases.

[0016] The door holding means is provided on the first support element.
A plug that is coupled to a fixed cylinder and fixed to one end of the rotating cylinder so that it rotates integrally with the rotating cylinder when the door is opened and closed, and has one or more engagement grooves at one end. A member, a fixed member coupled to the inside of the first fixed cylinder so as not to be rotatable, and between the plug member and the fixed member so as not to be rotatable by the fixed member and to be vertically movable. An actuating member that is fixed and has one or more protrusions that are engaged with one or more engagement grooves of the plug member, and a plurality of end portions that penetrate the fixing member and contact the actuating member. A pin member, a support member for supporting the other end portions of the plurality of pin members, and the operating member, the protrusion of which is engaged with the plug member via the support member and the plurality of pin members. To bias in the direction of engagement with the groove And a third coil spring.

The fixing member has a first flange portion and a first main body portion projecting from the center of the first flange portion. An outward spline is formed on an outer peripheral surface of the first main body portion, and An inward spline connected to the outward spline of the first body of the fixing member is formed on the inner peripheral surface. An inward spline is formed on the inner surface of the first fixed cylinder, an outward spline is formed on the outer peripheral surface of the first flange portion of the fixing member, and the upper end of the fixing member is engaged with a locking step formed on the first fixing cylinder. The fixing member is stopped and the snap ring is coupled to the fixed cylinder at the lower end of the fixing member, so that the fixing member is fixed in a state where the outward spline of the first flange portion is engaged with the inward spline of the first stationary cylinder. Is maintained. The engagement groove and the projection have a substantially rivet head cross-sectional shape. A small hole is formed on the bottom surface of the engagement groove, an axial groove communicating with the small hole is formed at an upper end portion of the plug member, and a cap projecting through the small hole is formed in the axial groove. Is inserted so as to be able to reciprocate, and inside the axial groove, the cap is projected through the small hole to apply a force in a direction for releasing the engagement between the engagement groove and the projection. And a closing member is fixed to the open end of the axial groove. The support member has a second flange portion and a second main body portion projecting from the center of the second flange portion, and the third coil spring is wound around an outer surface of the second main body portion of the support member. .

According to another aspect of the present invention, the door hinge device further comprises a door automatic closing means for automatically closing an open door when a fire occurs.

The door closing means includes an annular flange member fixed to the inner surface of the first fixed cylinder, an annular support plate soldered to the annular flange member and supporting the third coil spring, and the annular support member. A fastening member that penetrates the plate and the support member and is screwed to the inner peripheral surface of the first main body of the fixing member.

The fastening member is a bolt, and the bolt is fastened to the first main body of the fixing member during a process of soldering the annular support plate to the annular flange member.
The head portion presses the annular support plate against the annular flange portion, and when the soldering is completed, the head is released from the first main body portion of the fixing member by a predetermined distance. When the plate is separated from the annular flange member, a space in which the annular support plate can move is secured, and the elastic force of the third coil spring is reduced, so that the open door is automatically closed.

According to still another aspect of the present invention, the automatic door closing means includes an annular plate member for supporting a lower end of the third coil spring, and the fixed member penetrating the annular plate member and the support member. A fastening member screwed to the inner peripheral surface of the first main body of the member and interposed in a space between the annular plate member and the head portion of the fastening member, which is transmitted to the door in the event of a fire. A low melting point metal ring that is melted by the heat and formed so as to reduce the separation between the annular plate member and the fastening member.

According to still another aspect of the present invention, the automatic door closing means includes an annular plate member for supporting a lower end of the third coil spring, and the fixing member penetrating the annular plate member and the support member. A fastening member screwed to the inner peripheral surface of the first main body portion and having a head portion; a bar member having one end portion interposed in a space between the annular plate member and the head portion of the fastening member; The solenoid includes a solenoid surrounding the other end of the bar member, and a sensing unit that senses ambient temperature and controls power supply to the solenoid.

According to still another aspect of the present invention, the automatic door closing means includes an annular plate member for supporting a lower end of the third coil spring, and the fixed member penetrating the annular plate member and the support member. A fastening member screwed to the inner peripheral surface of the first main body of the member and having a head portion, a cylinder having one end closed and the other end open, and one end having the annular plate member and the fastening member The other end portion is interposed in the space between the head portion and a rod member disposed reciprocally inside the cylinder, and for urging the rod member in one direction inside the cylinder. A spring; and an annular member soldered to the other open end of the cylinder.

According to the above feature of the present invention, after the door hinge device is provided in a state where no torsional moment acts on the torsion coil spring, a tool is inserted into the tool insertion groove of the cap member and the rotary shaft is rotated, or the push shaft is pushed. By pushing the rod to separate the pawl of the pawl member from the ratchet of the inward ratchet wheel, the torsion moment of the torsion coil spring can be adjusted. It is performed in a simple, easy and fast manner, which increases the merchantability of the door hinge device, and there is no possibility that the door may close rapidly due to the elasticity of the door not being adjusted properly, which may cause injuries to visitors. Disappears. In addition, since the door hinge device is provided with the door open state maintaining means and the door automatic closing means, when the door is opened to the set specific angle, the door can be automatically maintained in the open state at that point. As a result, the convenience of door operation is improved, and if a fire occurs with the door opened and the temperature around the door rises, the door is automatically closed, improving safety. I do.

[0025]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Here, the same reference numerals are given to the same parts throughout the drawings.

The door hinge device 100 according to the first embodiment of the present invention includes a door hinge means, a door open state maintaining means, and a door automatic closing means. The door hinge means in the first embodiment will be described in detail.

FIG. 1 is a partially broken longitudinal sectional view showing the entire structure of a door hinge device according to a first embodiment of the present invention, and FIG. 2 constitutes a door hinge means provided at an upper portion in the door hinge device of FIG. FIG. 3 is an exploded perspective view showing each part. FIG. 3 shows the door hinge device of FIG. 1 in which the rotating shaft rotates clockwise to wind the torsion coil spring and the torsion moment of the torsion coil spring in order to increase the elastic force. FIG. 4 is a partially broken cross-sectional view for explaining the process of increasing
FIG. 5 shows a cross-sectional view taken along the line IV. FIG. 5 shows the door hinge device of FIG. 1 in which the pawl member is retracted by the pressing of the pressing piece to unwind the torsion coil spring in order to reduce the elastic force. 5 is a partially cutaway sectional view for explaining a process of reducing the torsional moment of the torsion coil spring, and FIG. 6 is a transverse sectional view taken along line VI-VI of FIG.

The door hinge device 100 according to the first embodiment of the present invention includes a pair of vertical support elements 102 and 103.
including. The first vertical support element 102 is fixed to the door and rotates integrally with the door, and the second vertical support element 10
3 is maintained in a state fixed to the door frame. First vertical support element 1 facing second vertical support element 103
02, a rotating cylinder 104 is integrally fixed to an intermediate portion of one end in the width direction, and both ends in the longitudinal direction of one end in the width direction of the second vertical support element 103 facing the first vertical support element 102. , A pair of fixed cylinders 105 and 106 are integrally fixed. The pair of fixed cylinders 105 and 106 are aligned with the lower end and the upper end of the rotating cylinder 104, respectively, and a pair of ring washers 130 and 131 are interposed between the pair of fixed cylinders 105 and 106 and the rotating cylinder 104, respectively. Is done. The plug member 107 is inserted into the first fixed cylinder 105 from below, and a screw formed at the upper end of the plug member 107 is screwed into the inner surface of the lower end of the rotating cylinder 104, so that the plug member 107 is Rotating cylinder 104
Fixed to At the upper end of the plug member 107, a support shaft portion 108 whose diameter decreases is formed to extend upward.

The lower end of the rotating shaft 109 is inserted into the rotating cylinder 104 from above, and the upper end of the rotating shaft 109 has a first outer diameter substantially the same as the inner diameter of the rotating cylinder 104.
An enlarged portion 110 and a second enlarged outer diameter portion 111 having an outer diameter larger than the inner diameter of the rotary cylinder 104 are sequentially formed on the upper side. The lower end of the rotating shaft 109 is provided on the free end of the support shaft 108 of the plug member 107, and the lower end of the rotating shaft 109 and the free end of the support shaft 108 have a pair of insertion grooves 1.
33 and 134 are respectively formed. A pair of insertion grooves 13
3 and 134, the both ends of the rod member 135 are inserted, respectively, and the bottom surfaces of the pair of insertion grooves 133 and 134 and the rod member 13 are inserted.
A pair of balls 112 and 113 are interposed between the both ends of the shaft 5 to guide the rotation of the rotating shaft 109. Inside the rotating cylinder 104, a torsion coil spring 114 is wound around the outer surface of the rotating shaft 109. The upper end of the torsion coil spring 114 is
The lower end of the torsion coil spring 114 is inserted into the spring fixing groove formed on the lower surface of the first enlarged outer diameter portion 110 and inserted into the spring fixing groove formed on the upper end surface of the plug member 107. Fixed. In FIG. 1, a torsion coil spring 114 is a counterclockwise torsion coil spring that is wound counterclockwise when viewed from above. Therefore, when the rotation shaft 109 rotates clockwise, the torsion coil spring 1
The torsion coil spring 114 receives the force in the unwinding direction when the rotating shaft 109 rotates counterclockwise when the torsion moment increases due to the effect of the force in the winding direction. Therefore, the torsional moment is reduced. At the upper end of the rotating cylinder 104, a rotating cylinder 10
An enlarged inner diameter portion 137 having an inner diameter larger than the inner diameter of No. 4 is formed, so that a step portion 136 is provided at a lower end portion of the enlarged inner diameter portion 137. When the rotating shaft 109 is inserted into the rotating cylinder 104, the lower end surface of the second enlarged outer diameter portion 111 of the rotating shaft 109 is seated on the step 136, and the upper end of the second enlarged outer diameter portion 111 The part projects slightly upward through the upper end of the second fixed cylinder 106 of the second vertical support element 103.

In the center of the upper end surface of the second enlarged outer diameter portion 111 of the rotating shaft 109, a first recess 115 extending downward is provided.
Is formed, and a second recess 116 extending downward is formed at the center of the bottom surface of the first recess 115. Second recess 11
6 has an inner diameter smaller than the first recess 115. As clearly shown in FIG. 4, the first recess 115 has a substantially rectangular cross-sectional shape, and the second recess 116 has a circular cross-sectional shape.
As shown in FIG. 1, a cutout 117 is formed on the right side wall of the second enlarged outer diameter portion 111 having the first recess 115, and the cutout 117 is formed to form the first recess 115.
Communicates with the outside not only in the axial direction but also in the radial direction. The bottom surface of the cutout portion 117 provided on the right side wall of the second enlarged outer diameter portion 111 is provided with a spring 14.
3 and a third recess 141 for accommodating the ball 142 are formed.

The second fixed cylinder 10 corresponding to the cutout 117
6, an inward ratchet wheel portion 118 is formed on the inner surface, and the inward ratchet wheel portion 118 has a number of ratchets. A pawl member 119 is provided in the first recess 115 of the rotating shaft 109 so as to be able to reciprocate in the radial direction through the cutout 117. At the rear end of the right end surface of the pawl member 119, one pawl 122 is integrally formed, and this pawl 122 is formed of a plurality of ratchets formed on the inward ratchet wheel 118 of the second fixed cylinder 106. Engage with either. A locking groove 143 is formed on the front bottom surface of such a pawl member 119 so that the ball 142 housed in the third recess 140 of the rotating shaft 109 is elastically engaged. Therefore, the second fixed cylinder 1
The pawl 122 engaged with one of the ratchets of the inward ratchet wheel part 118 of No. 06 can maintain a stable coupling state.

The pawl member 119 has a substantially rectangular opening 1
And a pawl member 119 having an opening 120.
Is a tapered surface 121. Pawl member 119
A cap member 128 is screwed onto the inner surface of the upper end portion of the rotating shaft 109 having the second enlarged outer diameter portion 111 at the upper portion of the rotating shaft. On the upper end of the cap member 128. Tool insertion groove 12
When an appropriate tool such as a wrench is inserted into the tool insertion groove 129 and turned, the rotating shaft 109 is rotated.
The push rod 1 is attached to the opening 120 of the pawl member 119.
23 is inserted. The lower end of the push rod 123 extends into the second recess 116, and the upper end of the push rod 123 passes through the cap member 128 and protrudes to the outside. An inverted triangular portion 124 is formed at an intermediate portion of the push rod 123, and the inverted triangular portion 124 can slide along the tapered surface 121 while being in contact with the tapered surface 121 of the pawl member 119. The first coil spring 1 is provided on the inner wall of the left side wall of the first recess 115.
One end of the first coil spring 126 is fixed.
Is fixed to the left end surface of the pawl member 119. The first coil spring 126 includes a pawl member 119
The pawl 122 is the inward ratchet wheel portion 118
In the direction of engagement with the ratchet.
A protruding portion 125 is formed at a portion near the lower end of the push rod 123, and a second coil spring 127 is provided inside the second recess 116. One end of the second coil spring 127 is in contact with the bottom surface of the second recess 116, and the other end of the second coil spring 127 is in contact with the lower surface of the protrusion 125 of the push rod 123. Second
The coil spring 127 has a function of pushing the push rod 123 upward. A protective cap 132 is screwed onto the outer peripheral surface of the cap member 128, and the protective cap 132 functions to protect a number of components protruding outside the second fixed cylinder 106.

The plurality of ratchets of the inward ratchet wheel portion 118 and the pawls 122 of the pawl members 119 are formed with an inclined surface and an upright surface, and as shown in FIG. The surface can rotate clockwise while sliding on the inclined surface of the ratchet, but cannot rotate counterclockwise due to the contact between the upright surface and the upright surface of the ratchet.

The door hinge device 100 according to the first embodiment configured as described above is mounted on a door and a door frame in a state where no torsional moment acts on the torsion coil spring 114, so that the mounting operation of the door hinge device 100 can be performed. Simple and easy to carry out. After the installation of the door hinge device 100 is completed, or when necessary during use of the door, an operation for adjusting the elastic force (elastic force) of the door hinge device 100, that is, the torsion coil spring 114 is performed.

When the elastic force of the door hinge device 100 is to be increased, the protective cap 132 is removed, a tool such as a wrench is inserted into the tool insertion groove 129 formed in the cap member 128 and rotated clockwise (FIG. 3).
When the cap member 128 is rotated in the clockwise direction, the rotation shaft 109 integrally fixed to the cap member 128 is rotated in the clockwise direction, and the pawl member 119 is inserted into the first rectangular recess 115 formed on the rotation shaft 109. By being reciprocally coupled, a clockwise force also acts on the pawl member 119. Thereby, the inclined surface of the pawl 122 of the pawl member 119 is rotated clockwise while sliding on the inclined surface of the ratchet of the inward ratchet wheel portion 118. At this time, as the pawl 122 rotated clockwise passes through the radially innermost portion of the corresponding one ratchet inclined surface, the pawl 122 is actuated by one ratchet by the urging force of the first coil spring 126. It is moved radially outward along the upright surface. The rotation of the pawl 122 moved radially outward in the counterclockwise direction as described above
Is prevented by the contact between the upright surface of the ratchet and the upright surface of the ratchet. Thereby, the counterclockwise rotation of the rotating shaft 109 is suppressed, so that the upper end is the first enlarged outer diameter portion 1 of the rotating shaft 109.
10, the torsion coil spring 114 whose lower end is fixed to the plug member 107 is wound by the angle at which the rotating shaft 109 is rotated clockwise, and the torsional moment increases. Therefore, as the number of ratchets through which the pawl 122 slides increases,
The torsional moment of the torsion coil spring 114 increases.

The rotating shaft 109 thus rotated is formed on the front bottom surface of the pawl member 119 with a ball 142 supported by a spring 141 while being engaged with the third concave portion 140 on the bottom surface of the cutout 117. By being engaged with and restricted by the locking groove 143, a stable coupling state is provided.

When the elastic force of the door hinge device 100 is to be reduced, after removing the protective cap 132, the upper end of the push rod 123 which penetrates the cap member 128 and protrudes upward is pushed in (see FIG. 5). When the push rod 123 is pushed in, the push rod 1
While the inverted triangular portion 124 formed in the middle of the slide member 23 slides along the tapered surface 121 of the pawl member 119, the pawl member 119 whose tip is regulated by the ball 142 is retracted into the first recess 115. Thereby, the engagement state between the pawl 122 of the pawl member 119 and the ratchet of the inward ratchet wheel 118 is released. Therefore, due to the torsion moment of the wound torsion coil spring 114, the rotating shaft 109
Can rotate freely in the counterclockwise direction, so that the torsional moment of the torsion coil spring 114 is reduced by the angle of the rotation shaft 109 rotated in the counterclockwise direction.

The door provided with the door hinge device 100 as shown in FIG.
0, that is, the torsion coil spring 114 is used so as to be opened by being rotated counterclockwise in a state where the elastic force (elastic force) is adjusted. That is,
When the door is rotated counterclockwise, the first vertical support element 102 fixed to the door is also integrally rotated counterclockwise, and the plug member fixed to the lower end of the first vertical support element 102 107 is also rotated counterclockwise. Therefore, when the lower end of the torsion coil spring 114 is fixed to the plug member 107, the torsion coil spring 114 receives a force in the winding direction, and the torsional moment further increases. Thereafter, when the hand that has opened the door is released, the door can be automatically rotated clockwise toward the closed position by the torsion moment of the torsion coil spring 114 that increases due to the opening.

Hereinafter, referring to FIG. 7 to FIG.
The door open state maintaining means and the door automatic closing means in the embodiment will be described in detail.

FIG. 7 is an exploded perspective view showing components constituting a door open state maintaining means and a door automatic closing means provided at a lower part in the door hinge apparatus of FIG. 1. FIG. FIG. 9 is a partially enlarged sectional view showing a state in which the door open state maintaining means is operating, and FIG.
FIG. 10 is a partially enlarged sectional view showing a state in which the door automatic closing means is operated in the door hinge device of FIG.
FIG. 3 is a cross-sectional view showing an operation structure of a cap provided inside a plug member.

A substantially circular opening is formed on the lower surface of the plug member 107, and an annular wall is formed around the circular opening. In the annular wall portion of the plug member 107, two engaging grooves 151 are formed so as to be circumferentially separated from each other by 180 °. This engagement groove 151 is
The rivet head has a sectional shape, and a small hole 152 is formed in the bottom surface of the engagement groove 151. Plug member 107
Around the supporting shaft portion 108, an axial groove 153 communicating with the small hole 152 is formed on the upper end surface of the plug member 107.
(See FIG. 10). A cap 155 that penetrates through the small hole 152 and protrudes downward is inserted into the axial groove 153 so as to be able to reciprocate. A spring 154 for applying a force in a direction that causes the cap 155 to protrude downward through the small hole 152 is inserted into the axial groove 153, and a closing member 156 is screwed into the upper end of the axial groove 153 by screwing. Fixed. A locking step 166 is formed at an intermediate portion in the axial direction of the first fixed cylinder 105 by reducing its inner diameter. At the upper part adjacent to the locking step 166, the inner surface of the first fixed cylinder 105 has an inward spline 1
An annular groove 167 is formed in the inner surface of the first fixed cylinder 105 at a lower portion adjacent to the locking step 166.

Below the plug member 107, the fixing member 1
The fixing member 157 has a first flange portion 158 and a first main body portion 159. Fixing member 15
Outer splines 160 and 161 are respectively formed on the outer peripheral surfaces of the first flange portion 158 and the first main body portion 159 of the fixing member 157, and a screw portion is formed on the inner peripheral surface of the first main body portion 159 of the fixing member 157. I have. Outward spline 160 formed on the outer peripheral surface of first flange portion 158 of fixing member 157
Is connected to the inward spline 164 of the first fixed cylinder 105, and a snap ring 169 is mounted in the annular groove 167 below the fixing member 157. Therefore,
The fixing member 157 cannot rotate or move in the axial direction. First flange portion 158 of fixing member 157
Are formed so that a number of holes 168 are circumferentially separated.

An operating member 162 is provided between the plug member 107 and the fixing member 157. This operating member 16
An inward spline 165 is formed on the inner peripheral surface of No. 2. Inward spline 165 formed on actuating member 162
Is connected to the outward spline 161 formed on the outer peripheral surface of the first main body 159 of the fixing member 157,
The actuating member 162 cannot rotate, and the first
It can move up and down along the main body 159. Two protrusions 16 are provided on the upper end surface of the operating member 162.
3 are formed so as to be separated from each other by 180 ° in the circumferential direction. The two projections 163 have a substantially rivet head cross-sectional shape, and can respectively engage with two engagement grooves 151 formed in the plug member 107. Below the fixing member 157, a number of pin members 170 are provided, and the number of pin members 170 are supported by the support members 171. The shank portions of the plurality of pin members 170 penetrate through the plurality of holes 168 formed in the fixing member 157 and project upward to contact the lower surface of the operating member 162. The support member 171 supporting the large number of pin members 170 is the second member.
It has a flange portion 172 and a second main body portion 173, and the outer peripheral surface and the inner peripheral surface of the support member 171 are processed smoothly. On the outer peripheral surface of the second main body portion 173 of the support member 171,
The third coil spring 174 is wound.

Below the third coil spring 174, an annular flange member 175 is fixed to the inner peripheral surface of the first fixed cylinder 105 by an appropriate means known in the art such as welding. An annular support plate 176 is fixed to a lower surface of the annular flange member 175 by a soldering portion 177. The upper end of the bolt 178 is connected to the annular support plate 176.
The support member 171 extends upward through the second main body 173 and is screwed to a screw formed on the inner peripheral surface of the first main body 159 of the fixing member 157. The bolt 178 has a head portion 179, and the head portion 179 is
76 and is maintained at a predetermined distance. A protective cap 180 is fixed to the lower end of the first fixed cylinder 105.
It functions to protect a number of parts protruding downward. The third coil spring 174 pushes the operating member 162 upward via a large number of pin members 170 by pushing the support member 171 upward. Therefore, the operating member 162 receives the action of the force in the direction in which the protrusion 163 is engaged with the engagement groove 151 of the plug member 107.

The operation of the door open state maintaining means and the door automatic closing means in the door hinge apparatus 100 according to the present embodiment having the above-described structure will be described in detail.

As shown in FIG. 1, when the engagement groove 151 of the plug member 107 and the protrusion 163 of the operation member 162 are located at positions shifted from each other, when the door is opened and rotated counterclockwise to a predetermined angle. , The plug member 107 fixed to the rotating cylinder 104 rotates integrally with the operating member 1.
The engagement groove 151 formed on the plug member 107 and the protrusion 163 formed on the actuating member 162 coincide with each other in the vertical direction. At this time, the operating member 162 moves upward along the outward spline 161 formed on the outer peripheral surface of the first main body portion 159 of the fixing member 157 by the urging force of the third coil spring 174, and the protrusion of the operating member 162 The part 163 is engaged with the engagement groove 151 of the plug member 107. As a result, the open state of the door is maintained as long as a clockwise force for closing the door again is not applied to the door.

When a slight force is applied clockwise while the door is kept open, the operating member 16
The second protrusion 163 is disengaged from the engagement groove 151 of the plug member 107, and the door moves to the closed position again by the torsion force of the torsion coil spring 114 wound on the outer peripheral surface of the rotating shaft 109.

If a fire occurs in a state where the door is kept open, heat is transmitted to the door, and the soldering portion 177 fixing the annular support plate 176 to the lower surface of the annular flange member 175 melts. As a result, the annular support plate 176 is separated from the annular flange member 175, whereby the compressed third coil spring 174 returns,
The upward biasing force of the third coil spring 174 decreases.
Therefore, the torsion force of the coil spring 114 wound on the outer peripheral surface of the rotating shaft 109 becomes relatively high, so that the door rotates clockwise and closes automatically. At this time, the cap 155 inserted in the axial groove 153 of the plug member 107 projects downward through the small hole 152 by the urging force of the spring 154, and the engagement groove 15
Helps the protrusion 163 separate from the one.

In a state where the third coil spring 174 is interposed between the support member 171 and the annular support plate 176 in a compressed state, the bolts 178 are fixed first to fix the annular support plate 176 to the annular flange member 175. In a state in which it is fastened upward along a screw portion formed on the inner peripheral surface of the first main body portion 159 of the fixing member 157, so that the annular support plate 176 is soldered to the annular flange member 175. There is no need to hold the annular support plate 176 with another tool or the like. When the soldering operation is completed, the bolt 178 is loosened again, and the head portion 17 of the bolt 178 is loosened.
By setting 0 to be separated from the annular support plate 176 by a predetermined distance, a sufficient distance for the annular support plate 176 to move downward due to melting of the soldering portion 177 in the event of a fire can be secured.

FIG. 11 is a partially enlarged sectional view showing a state in which the door open state maintaining means is operated in the door hinge device according to the second embodiment of the present invention, and FIG. FIG. 4 is a partially enlarged cross-sectional view showing a state where the automatic closing means is operating.

The door hinge device 20 according to the second embodiment
0 is the door hinge device 1 of the first embodiment except that the structure of the automatic door closing means is different from that of the first embodiment.
Since it is the same as 00, the following description will be given of only the portions different from the door hinge device 100 of the first embodiment, and the same reference numerals will be used for the same portions.

The door hinge device 200 in the present embodiment
, The third coil spring 174 is supported by the annular plate member 201,
A low melting point metal ring 202 is interposed between the head ring 179 and the head portion 179 of the bolt 178. Such a low-melting metal ring 202 is provided in a form surrounding the outer peripheral surface of the bolt 178. When the door is heated to a certain temperature by a fire, the ring is melted and removed, so that the annular plate member 201 is removed. It is preferably formed of lead such that the distance between the bolt 178 and the head 179 of the bolt 178 is reduced.

Therefore, when a fire occurs in a state where the door is kept open, the low-melting metal ring 202, usually formed of lead, is melted by the heat transmitted to the door. The annular flange member 201 pressing the coil 174 is moved to the head 1 of the bolt 178.
79. As a result, the third coil spring 174 that has been compressed returns to the third
The upward biasing force of the coil spring 174 decreases. Therefore, the torsional force of the torsion coil spring 114 wound on the outer peripheral surface of the rotating shaft 109 is relatively increased, so that the door is rotated clockwise, and the door that has been opened can be automatically closed. become.

FIG. 13 is a partially enlarged sectional view showing a state in which the door open state maintaining means is operated in the door hinge device according to the third embodiment of the present invention. FIG. FIG. 15 is a partially enlarged sectional view showing a state in which the automatic closing means is operating, and FIG.
13 is a bottom view showing the structure of the door automatic closing means used in the door hinge device of FIG.

The door hinge device 30 in the third embodiment
0 is the same as the door hinge device 100 of the first embodiment except that the structure of the door automatic closing means is different from that of the first embodiment. Therefore, hereinafter, only the portions different from the door hinge device 100 of the first embodiment will be described, and the same reference numerals will be used for the same portions.

In the door hinge device 300 of this embodiment, the third coil spring 174 is
01, one end of the bar member 302 is interposed between the annular plate member 301 and the bolt 178. One end of the bar member 302 is formed so as to almost surround the outer peripheral surface of the bolt 178. Bar member 30
The other end of 2 protrudes outside through the protective cap 306, and the other end of the bar member 302 protruding outside is inserted into the solenoid 303. The solenoid 303 is connected to the sensing unit 304, and the sensing unit 304 is connected to the emergency power supply 30.
5 is connected. Therefore, when a fire occurs, the sensing unit 304 senses the surrounding temperature, and when the sensed temperature is higher than a predetermined temperature, the power is applied to the solenoid 303, whereby the bar member 302 is pulled out. Thus, an open door can be automatically closed.

FIG. 16 is a sectional view showing the structure of the automatic door closing means used in the door hinge device according to the fourth embodiment of the present invention.

The door hinge device of the fourth embodiment of the present invention is the same as the door hinge device 300 of the third embodiment except that the structure of the automatic door closing means is different from that of the third embodiment. In the following, only portions different from the door hinge device 300 of the third embodiment will be described, and the same reference numerals will be used for the same portions.

In the door hinge device of the present embodiment, the coil spring is supported by the annular plate member, and one end of the rod member 401 is interposed between the annular plate member and the head of the bolt 178. One end of the rod member 401 is formed so as to almost surround the outer peripheral surface of the bolt 178. Rod member 401
The other end of the rod member 401 penetrates through the protective cap and protrudes to the outside. The other end of the rod member 401 protruding to the outside extends to the inside of the cylinder 402. One end of the cylinder 402 is closed and the other end is open. Cylinder 402
The spring 403 is disposed inside the
Reference numeral 3 functions to push the other end of the rod member 401 in a direction away from the bolt 178. At the other end of the cylinder 402, an annular member 404 is provided on the inner surface of the cylinder 402.
Are fixed by the soldering section 405. At this time, since the annular member 404 is supported by an appropriate supporting means, it can be seen that the spring 403 can be soldered in a compressed state. Therefore, when a fire occurs, when the surrounding temperature rises, the soldering portion 405 melts, and the spring 403 pushes the rod member 401 away from the bolt 178, thereby returning the spring. The door that has been open will be automatically closed.

Although the present invention has been described based on specific preferred embodiments, the present invention is not limited to these embodiments, and departs from the spirit and scope of the present invention defined by the appended claims. Those skilled in the art can easily understand that various modifications and changes can be made without departing from the scope of the present invention.

[0061]

According to the construction of the present invention described above, after the door hinge device is provided without any torsional moment acting on the torsion coil spring, the tool is inserted into the tool insertion groove of the cap member and the rotary shaft is rotated. Alternatively, the torsion moment of the torsion coil spring can be adjusted by pressing the push rod to separate the pawl of the pawl member from the ratchet of the inward ratchet wheel. Competence work is performed in a simple, easy and fast manner,
The merchantability of the door hinge device is increased, and there is no possibility that the door is closed quickly because the elastic force of the door is not properly adjusted and the occupant is injured.

Further, since the door hinge device is provided with the door open state maintaining means and the door automatic closing means, when the door is opened to the set specific angle, the door can be automatically maintained in the open state at that point. As a result, the convenience of the door operation is improved, and if a fire occurs with the door opened and the temperature around the door rises, the door is automatically closed, which is safe. The performance is improved.

[Brief description of the drawings]

FIG. 1 is a partially broken longitudinal sectional view showing the entire structure of a door hinge device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing components constituting a door hinge means provided at an upper part in the door hinge device according to the first embodiment of the present invention.

FIG. 3 is a perspective view of the door hinge device according to the first embodiment of the present invention, in which the rotating shaft rotates clockwise to wind the torsion coil spring to increase the torsional moment of the torsion coil spring in order to increase the elastic force. FIG. 5 is a partially broken sectional view for explaining a process.

FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 3;

FIG. 5 is a perspective view of the door hinge device according to the first embodiment of the present invention. In order to reduce the elastic force, the pawl member is retracted by the pressing of the pressing piece to unwind the torsion coil spring, thereby torsion of the torsion coil spring. It is a fragmentary sectional view for explaining a process of reducing a moment.

FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 5;

FIG. 7 is an exploded perspective view showing components constituting a door open state maintaining means and a door automatic closing means provided at a lower part in the door hinge device according to the first embodiment of the present invention.

FIG. 8 is a partially enlarged cross-sectional view showing a state in which the door open state maintaining means is operating in the door hinge device according to the first embodiment of the present invention.

FIG. 9 is a partially enlarged cross-sectional view showing a state where the door automatic closing means is operating in the door hinge device according to the first embodiment of the present invention.

FIG. 10 is a sectional view showing an operation structure of a cap provided inside the plug member according to the first embodiment of the present invention.

FIG. 11 is a partially enlarged cross-sectional view illustrating a state in which a door open state maintaining unit is operating in the door hinge device according to the second embodiment of the present invention.

FIG. 12 is a partially enlarged cross-sectional view showing a state in which a door automatic closing unit is operating in a door hinge device according to a second embodiment of the present invention.

FIG. 13 is a partially enlarged cross-sectional view showing a state in which a door open state maintaining unit is operating in the door hinge device according to the third embodiment of the present invention.

FIG. 14 is a partially enlarged cross-sectional view illustrating a state in which a door automatic closing unit is operating in the door hinge device according to the third embodiment of the present invention.

FIG. 15 is a bottom view showing the structure of a door automatic closing means used in a door hinge device according to a third embodiment of the present invention.

FIG. 16 is a sectional view showing a structure of a door automatic closing means used in a door hinge device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Door hinge device 102, 103 Vertical support element 104 Rotating cylinder 105, 106 Fixed cylinder 107 Plug member 108 Supporting shaft part 109 Rotating shaft 110 First enlarged large diameter part 111 Second enlarged large diameter part 112, 113 Ball 114 Torsion coil spring 115 first recess 116 second recess 117 cutout 118 inward ratchet wheel 119 jaw member 120 open portion 121 tapered surface 122 nail 123 push rod 124 inverted triangular portion 125 projecting portion 126 first coil spring 127 second coil spring 128 cap member 129 Tool insertion groove 130, 131 Ring washer 132 Protective cap 133, 134 Insertion groove 135 Bar member 136 Stepped portion 137 Enlarged inner diameter portion 140 Third concave portion 141 Spring 142 143 locking groove 151 engaging groove 152 small hole 153 axial groove 154 spring 155 cap 156 closing member 157 fixing member 158 first flange portion 159 first body portion 160, 161 outward spline 162 operating member 163 protrusion 164, 165 Inward spline 166 Locking step 167 Annular groove 168 Hole 169 Snap ring 170 Pin member 171 Support member 172 Second flange portion 173 Second body portion 174 Third coil spring 175 Ring flange member 176 Ring support plate 177 Soldering portion 178 Bolt 179 Head part 180 Protective cap 200 Door hinge device 201 Ring plate member 202 Low melting point metal ring 300 Door hinge device 301 Ring plate member 302 Bar member 303 Solenoid 304 Sensing unit 305 Emergency power supply 306 Protective cap 401 Rod member 402 Cylinder 403 Spring 404 Ring member 405 Soldering part

Claims (21)

[Claims] 1. A door hinge device, comprising: a first support element fixed to a door and having a rotating cylinder; and a second support element fixed to a door frame and having a pair of fixed cylinders respectively disposed at both ends of the rotating cylinder. Providing a support element and torsional force to maintain the door in a closed position;
Door hinge means for further increasing the torsional force when the door is opened, so that the door automatically returns to the closed position when the external force applied to the door is removed, and at a specific open position of the door. A door hinge device comprising: a door open state maintaining means for maintaining an open state of the door. 2. The door hinge means is connected to a first fixed cylinder of a second support element, and a plug member fixed to one end of the rotary cylinder, and one end is connected to a second fixed cylinder of the second support element. It penetrates and is inserted into the inside of the rotating cylinder, is rotatably supported by the plug member, has a large-diameter portion formed at the other end portion, and a first concave portion having an open side is formed at the large-diameter portion. A rotary shaft having a second concave portion formed on the bottom surface of the first concave portion, and wound around the rotary shaft inside the rotary cylinder, one end portion being fixed to the plug member, and the other end portion being A torsion coil spring fixed to the large-diameter portion of the rotary shaft; and a first recessed portion of the large-diameter portion of the rotary shaft, penetrating through the opened one side portion and reciprocally movable in a radial direction. Is provided, an open portion one surface of which is a tapered surface is formed, (2) a pawl member formed with a pawl engaged with any one of a number of ratchets of an inward ratchet wheel portion formed on an inner peripheral surface of the fixed cylinder; and an inner surface of a large-diameter portion of the rotating shaft having the first recess. And a cap member fastened to the second concave portion, one end portion of which is located inside the second concave portion, the other end portion penetrates the cap member and protrudes to the outside, and the middle portion has a tapered surface of an open portion of the pawl member. A push rod having an inverted triangular portion slidable therein; and urging the pawl member within the first recess in a direction in which the pawl is engaged with the inward ratchet wheel of the second fixed cylinder. And a second coil spring for biasing the push rod toward the cap member inside the second concave portion. Door hinge device of claim 1, wherein. 3. The door hinge device according to claim 1, wherein the first and second support elements are a pair of vertical support elements arranged in parallel in a vertical direction. 4. The enlarged diameter portion has a first enlarged outer diameter portion having substantially the same outer diameter as the inner diameter of the rotating cylinder, and a second enlarged outer diameter portion having an outer diameter larger than the inner diameter of the rotating cylinder. An enlarged inner diameter portion having an inner diameter larger than the inner diameter of the rotating cylinder is formed at the other end of the rotating cylinder, so that a step portion is formed on the inner surface of the rotating cylinder, and the second enlarged outer diameter is formed at the step portion. The door hinge device according to claim 2, wherein one end surface of the portion is seated. 5. The door hinge device according to claim 2, wherein a flange portion on which one end of the second coil spring is seated is formed at a portion of the push rod close to the one end. 6. The plug member has a support shaft extending into the rotary cylinder, and a pair of insertion grooves are formed at a free end of the support shaft and one end of the rotary shaft, respectively.
Both ends of the rod member are inserted into the pair of insertion grooves, respectively, and a pair of balls are interposed between the bottom surfaces of the pair of insertion grooves and both end portions of the rod member, respectively. To guide both ends of the rotary cylinder and the first
3. The door hinge device according to claim 2, wherein a pair of ring washers are interposed between the first and second fixed cylinders. 7. When the pawl of the pawl member is engaged with any one of a number of ratchets formed on the inward ratchet wheel portion of the second fixed cylinder, the rotating shaft can rotate in only one direction and in the other direction. Cannot rotate, and when the rotating shaft is rotated in the one direction by a tool inserted into the tool insertion groove of the cap member, the torsion coil spring receives a force action in a winding direction to generate a torsional moment. Is further increased, and when the push rod is pushed in to overcome the urging force of the first and second coil springs to retract the pawl member into the first recess, the engagement state between the pawl and the ratchet is released. 3. The torsion coil according to claim 2, wherein the torsion moment is reduced by unwinding the wound torsion coil spring. Door hinge device. 8. The torsion coil spring is a counterclockwise torsion coil spring wound in a counterclockwise direction, wherein the one direction is a clockwise direction and the other direction is a counterclockwise direction. The door hinge device according to claim 7, wherein when the cylinder is rotated in the counterclockwise direction, the torsion coil spring is subjected to a force in the winding direction to increase its torsional moment. 9. A cut-out portion is formed on the right side of the large-diameter portion of the rotating shaft, a third recess for accommodating a spring and a ball is formed on the bottom surface of the cut-out portion, and a front bottom surface of the pawl member is formed. 8. The door hinge device according to claim 2, wherein a locking groove is formed so that a ball housed in the third recess is elastically engaged. 10. The door holding means is coupled to a first fixed cylinder of a second support element and fixed to one end of the rotating cylinder, so that the door is opened and closed to rotate integrally with the rotating cylinder. A plug member having one or more engagement grooves formed at one end thereof; a fixing member coupled to the inside of the first fixing cylinder so as not to rotate; and between the plug member and the fixing member. An operating member fixed to the fixing member so as not to be rotatable and movable vertically, and formed with one or more projections engaged with one or more engagement grooves of the plug member; A plurality of pin members, one end of which penetrates the fixing member and comes into contact with the operating member; a support member for supporting the other end of the plurality of pin members; and the support member and the plurality of pin members. The operating member through its projection There door hinge device according to claim 1, characterized in that it comprises a third coil spring for urging in a direction to be engaged with the engagement groove of the plug member. 11. A fixing member having a first flange portion and a first main body portion protruding from a center of the first flange portion.
The outward spline is formed on an outer peripheral surface of the main body, and an inward spline is formed on an inner peripheral surface of the operating member, the inward spline being coupled to the outward spline of the first main body of the fixing member. The door hinge device according to any one of the preceding claims. 12. An inward spline is formed on an inner surface of the first fixed cylinder, an outward spline is formed on an outer peripheral surface of the first flange portion of the fixing member, and an upper end of the fixing member is formed on the first fixing cylinder. The fixing step is locked, and the snap ring is coupled to the fixed cylinder at the lower end of the fixing member, whereby the outward spline of the first flange portion is engaged with the inward spline of the first fixing cylinder. The door hinge device according to claim 10, wherein the door hinge device is fixedly maintained in an extended state. 13. The door hinge device according to claim 10, wherein the engaging groove and the projection have a substantially rivet head cross-sectional shape. 14. A small hole is formed in a bottom surface of the engagement groove, an axial groove communicating with the small hole is formed at an upper end of the plug member, and the axial groove penetrates the small hole. And a cap that projects and reciprocates is inserted and inserted into the axial groove so that the cap protrudes through the small hole in a direction to disengage the engagement state between the engagement groove and the projection. The door hinge device according to claim 10, wherein a spring for applying a force is inserted, and a closing member is fixed to an open end of the axial groove. 15. The support member has a second flange portion and a second main body projecting from the center of the second flange portion,
The door hinge device according to claim 1, wherein the third coil spring is wound around an outer surface of a second main body of the support member. 16. The door hinge device according to claim 1, further comprising automatic door closing means for automatically closing an open door when a fire occurs. 17. An annular flange member fixed to an inner surface of the first fixed cylinder, an annular support plate soldered to the annular flange member and supporting the third coil spring, wherein the door closing means is; 17. The door hinge device according to claim 16, further comprising a fastening member that penetrates the annular support plate and the support member and is screwed to an inner peripheral surface of the first main body of the fixing member. 18. The fastening member is a bolt, and the bolt is fastened to a first main body of the fixing member in a process of soldering the annular support plate to the annular flange member, and a head portion thereof is provided. When the annular support plate is pressed against the annular flange portion and the soldering is completed, the annular support plate is released from the first main body portion of the fixing member by a predetermined distance. 16. The door in an open state is automatically closed by a space in which the annular support plate can move when separated from the member, and the elastic force of the third coil spring is reduced. The door hinge device according to any one of the preceding claims. 19. The door automatic closing means, wherein: an annular plate member for supporting a lower end of the third coil spring; and a first body portion of the fixed member penetrating the annular plate member and the support member. A fastening member screwed to the peripheral surface and having a head portion, interposed in a space between the annular plate member and the head portion of the fastening member, and melted by heat transmitted to the door at the time of fire, 17. The door hinge device according to claim 16, further comprising a low-melting-point metal ring formed so as to reduce a gap between the annular plate member and the fastening member. 20. An inner periphery of a first main body portion of the fixing member, wherein the door automatic closing means includes: an annular plate member that supports a lower end of the third coil spring; A fastening member screwed to the surface and having a head portion, a bar member having one end portion interposed in a space between the annular plate member and the head portion of the fastening member, and surrounding the other end portion of the bar member 17. The door hinge device according to claim 16, further comprising: a solenoid that detects an ambient temperature and controls a power supply to the solenoid by detecting an ambient temperature. 21. The door automatic closing means, wherein: an annular plate member for supporting a lower end of the third coil spring; and a first main body of the fixed member penetrating through the annular plate member and the support member. A fastening member screwed to the peripheral surface and having a head portion; a cylinder having one end portion closed and the other end portion opened; and a space between one end portion of the annular plate member and the head portion of the fastening member. A rod member disposed reciprocally inside the cylinder, a spring for urging the rod member in one direction inside the cylinder, and the cylinder being opened. The door hinge device according to claim 16, further comprising an annular member soldered to the other end of the door hinge.