JPH09250272A - Automatic return device for door - Google Patents

Abstract

PROBLEM TO BE SOLVED: To be opened by pushing a door with a manual force, etc., and automatically closed by releasing the hand, in the door for a refrigerator, etc. SOLUTION: A door body fitting frame 10 whose dimension is set to be sufficiently larger than the thickness of a wall, where a door 1 is fitted, is provided with a projecting frame part 10a projected to the inside or the outside, the door which is fitted thereto so as to be freely opened/closed by support shafts 2, the upper ends of the support shafts projected to the top of the frame, sprockets 3 attached thereto, a chain 4 of a prescribed length which is wound around the sprockets in such a state as setting its left/right to the same length, shafts 5 which are connected to both ends of the chain and inserted in a support mount 7 having the upper frame, where the shafts are fixed, till the stopper nuts 6 of the shafts are collided therewith, and coil springs 9 which are provided between the support mount and spring bearing nut 8. The opening operation of the door rotates the sprockets 3 so as to pull the chain and the shafts and compression of the coil springs generates an elastic restitutive force so as to automatically return the door to its closed state.

Description

Detailed Description of the Invention

[0001]

[Industrial application] A door that is installed at the entrance of a freezer, refrigerator, etc. to perform heat insulation, dust proofing, etc., and opens when you press it manually, and automatically closes when you release it. Provided is an automatic door returning means which can be applied to a heavy door such as a heat insulating door of a freezer.

[0002]

2. Description of the Related Art At present, doors are installed at entrances (for people, carts, forklifts, etc.) of large freezers, refrigerators, other warehouses, various factories, etc. to perform heat insulation, dust proof, wind proof, odor proof, insect proof, etc. The automatic return door (auto return swing door) that opens when pushed by human power and automatically closes when released when it is released does not use power such as electricity.
Therefore, it is often used because of its merit that it does not require maintenance such as power consumption and inoperability due to power failure.

However, as a conventional automatic return door of this kind,
For example, a method that uses the spring's bending and elastic restoring force, such as closing (restoring) the elastic coiling force from the coil spring winding at the hinge part due to the door opening and closing, or the hinge part at the top of the door is used. Widely used is a system in which a door that is tilted and pivotally supported with respect to a vertical mounting vertical frame and returns and rotates by its own weight to close the door is used. There were the following issues.

[0004]

Problem to be Solved by the Invention When a door (single-opening door or double door with double doors) is opened manually and then released and automatically returned to the closed position, the original position cannot be restored accurately. That is, the doors do not completely open, and particularly in the case of the double doors that are double doors, the two doors do not close accurately and a gap is created, thus impairing the effects of heat insulation, dust prevention, and the like.

The above problems often occur especially when the door is released from a slightly opened state, or when the door is slightly opened due to wind. The reason is that the spring return method is insufficient in return spring force, and the automatic return method does not generate sufficient automatic turning force at a small opening angle.

The above incompletely closed door is a serious problem from the viewpoint of energy loss due to poor insulation, especially in the case of freezers and refrigerators.

Further, as described above, the conventional method has a problem that it is difficult to apply it to a particularly heavy door such as a heat insulating door of a freezer or a refrigerator because the automatic return force of the door is small. That is,
The conventional automatic return means of the door is not limited to the above-mentioned conventional example, and any type of the automatic return means can be used as the automatic return means within the range of the door itself or the inner surface side of the mounting frame of the door around the door, especially the hinge portion thereof. Because of this, there was an inevitable space limitation, and it was difficult to install a large or powerful automatic return means.

That is, in the case of the conventional spring force method, it is usually wound around the hinge portion of the door, but since there is no space as described above, the strength of the spring that can be used is also limited.
Not suitable for heavy doors.

In the case of the self-weight return system, it is not possible to obtain sufficient turning force for turning the heavy door unless the tilt angle of the door is increased. However, if the tilt angle is increased, the shape of the door and the combination of both doors are adjusted. Insulation processing such as packing of eyes and gaps with the mounting frame,
In addition, there are problems such as difficulty in improving the accuracy.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional heavy door such as a freezer and a refrigerator, and naturally, can automatically be used for other doors. It is intended to provide a means.

Therefore, the present invention firstly invented an automatic return means provided with a turning force sufficient to rotate the heavy door from the opened state to restore and close it, and to always restore the door to an accurate closed position.

Attention is also paid to the fact that all of the conventional problems are caused by providing the automatic return means within the range of the door itself and its mounting frame, and at the same time, the automatic return means of the present invention is better than the conventional one. Also has a large installation space,
Since it can not be installed as it is, the idea is greatly changed, and the automatic return means is not provided in the range inside the door itself and its mounting frame as in the past, and the upper frame of the mounting frame (top The idea is to provide enough space for installation on the board), and to do so,
If the mounting frame of the door is mounted on the same plane as the wall with the same thickness dimension as the surrounding wall as in the conventional case, the upper frame (top plate) of the mounting frame is naturally a wall, and the automatic return means Since there is no space provided with, the thickness of the mounting frame is set larger than the thickness of the wall, and when the mounting frame is fitted and installed on the wall, the thickness of the large portion is Is provided as a protruding frame portion that protrudes from the wall surface to the inside or outside of the refrigerator,
The conventional problem is solved by attaching a door to the inside of the protruding frame portion and providing an automatic return means on the upper frame.

[0013]

A support shaft pivotally supporting a door to rotate and open and close the door, a sprocket provided to rotate by the rotation of the support shaft, and a sprocket hung around the sprocket in substantially equal lengths to the left and right. A chain having a set length, shafts connected to the left and right ends of the chain, a support through which the shaft is inserted until its stopper collides, and a coil spring stretched between the rear ends of the shaft,

The human power of the door in the closed position pushes and opens the support shaft and the sprocket to rotate the shaft and the chain and shaft to compress the coil spring. When the door is released in the open position, the coil spring restores and expands. With the automatic return means of the door, the chain and shaft are restored until the stopper collides with the support, and the sprocket and the support shaft are rotated to restore and close the door to the original position. Has been solved,

Further, according to the present invention, the thickness of the mounting frame for mounting the door on the inside is set to be larger than the thickness of the wall around the door for mounting the door of a freezer or the like, and the mounting frame is mounted. When it is fitted and installed on the wall, the part with the large thickness dimension is provided as a protruding frame part that protrudes from the wall surface to the inside or the outside of the refrigerator,

A door is attached to the inside of the projecting frame portion such that the door can be opened and closed by a support shaft, and the upper end of the support shaft is projected onto the upper frame of the projecting frame portion, and a sprocket is attached to the projecting support shaft. The chain of the set length is hung around the left and right approximately the same length, the shaft is connected to the left and right ends of the chain, and the shaft is supported by inserting it on a support stand fixed on the upper frame until the stopper collides. Along with
The problem is solved by an automatic door return means provided with a coil spring stretched between the support and the rear end of the shaft.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. A sprocket 3 fixed to the upper end of the support shaft so as to rotate in unison with the rotation of the support shaft 2, a chain 4 of a set length wound around the sprocket 3 in a substantially equal length on the left and right, and the left and right ends of the chain 4 respectively. From a connected shaft 5, a coil spring 9 or the like stretched between a support base 7 that is inserted until a stopper nut 6 screwed on the tip of the shaft 5 collides, and a spring receiving nut 8 screwed on the rear end of the shaft 5. Becomes

The support shaft 2 and the sprocket 3 are rotated by pushing and opening the door 1 at the door closing position P ₁ by human force or the like, and the chain 4 and the shaft 5 are pulled to compress the coil spring 9 and the door opening position P ₂ is reached. When the door 1 is released, the coil spring 9 is restored and expanded, and the chain 4 and the shaft 5 are restored until the stopper nut 6 collides with the support base 7, and the sprocket 3 is released.
And a means for automatically returning the door, which is provided so that the support shaft 2 rotates to perform the restoring and closing movement of the door 1 to the original position P ₁ .

Further, according to the present invention, the thickness of the mounting frame 10 for mounting the door 1 inside is set to be larger than the thickness of the wall around the door 1 of the freezer or the like to which the door 1 is mounted. When the mounting frame is fitted and installed at the entrance / exit setting position of the wall (side wall panel, etc.), the large thickness part is from the wall 11 surface to the inside 12
Alternatively, it is provided so as to be the protruding frame portion 10a protruding to the outside 13 of the refrigerator,

The door 1 is attached to the inside of the projecting frame portion 10a so as to be openable and closable with the support shaft 2, and the upper end of the support shaft 2 is projected onto the upper frame (top plate) of the projecting frame portion 10a. The sprocket 3 is attached to the supported shaft, and the sprocket 3
The chain 4 having the set length is hung around the left and right sides substantially equally, the shaft 5 is connected to the left and right ends of the chain 4, and the shaft 5 is attached to the support base 7 fixed on the upper frame of the shaft 5 and the stopper nut 6 thereof. Is an automatic return means for the door, which is inserted and supported until a collision occurs and is provided with a coil spring 9 stretched between the support base 7 and the spring receiving nut 8.

The position of the stopper nut 6 screwed on the tip of the shaft 5 is inversely proportional to the left and right, for example, the right stopper nut 6 is advanced by 5 mm and the left stopper nut 6 is moved by 5 mm.
It is provided so as to finely adjust the angle of the door 1 at the closed door position P ₁ by screwing back, adjusting and moving to slightly adjust and rotate the sprocket 3 and the support shaft 2.

A spring receiving nut 8 screwed on the rear end of the shaft 5.
By adjusting the distance between the support base 7 and the rear end of the shaft 5 by moving the screw back and forth, the spring force of the coil spring 9 stretched between them, that is, the return turning power of the door is adjusted to be strong or weak.

In the illustrated example, the chain 4 is provided around the sprocket 3, but the present invention is provided with a chain or the like, that is, a chain or a timing belt or other power transmission means is provided around the sprocket.

If necessary, the tension roller 14 is provided on the left and right sides of the chain 4 in order to suppress the slack of the left or right chain 4 that occurs when the sprocket 3 rotates by pulling the right or left side of the chain 4 or the like. Be prepared for.

According to the present invention, the shaft 5 is provided at the left and right ends of the chain or the like.
4, the guide shaft 15 and the tension springs 16 are connected to the left and right ends of the chain 4 and the like as shown in FIG. 4, and the ends of the tension springs 16 are fixedly attached to a part of the upper frame 10b to open the door 1. Sometimes, the guide shaft 15 is pulled by the chain 4 or the like.
Sliding, the tension spring 16 expands, and the door opening position P
_{When the} door 1 is released at ₂ , the guide shaft 15 and the chain 4 are pulled by the restoring contraction force of the tension spring 16 to rotate the sprocket 3 and the support shaft 2 to restore the door 1 in the closed and restoring state. Including return means,

Further, as shown in FIG. 4, the hydraulic cylinder 17 or the rod 17a of the air cylinder is connected to the left and right ends of the chain 4 and the like, like the ordinary door check.
The rod 17a is pulled by the chain 4 when the door 1 is opened.
Is lightly extended, and when the door 1 is released at the door opening position P ₂ , the rod 17a is strongly reduced by hydraulic pressure to strongly pull the chain 4 and the like, and the door 1 is closed and restored. It includes means.

[0027]

When the door 1 (single-opening door, double door with double doors) is opened from the closed position P _{1 by} human power or the like, the support shaft 2 and the sprocket 3 integrated with the door 1 are rotated, and the chain 4 and the shaft are pulled and the coil is pulled. Compress the spring 9.

Next, when the door 1 is released in the open state, the compressed coil spring 9 is expanded and restored, and the shaft and the chain 4 are restored until the stopper nut 6 collides with the support base 7 and stops, and the sprocket 3 is released. Also, the support shaft 2 rotates and the door 1 closes and stops at the door closing position P ₁ .

The above-mentioned operation moves the door 1 from the outside of the cabinet to the inside of the cabinet,
On the contrary, when the door is opened from the inside to the outside and the door automatically returns and closes, or when the left and right doors of the double door are opened and closed, the direction of rotation of the door, the support shaft and the shaft changes respectively. The same applies to the case.

[0030]

[Effect] When the door opens and closes, the spindle and sprocket rotate, pulling the chain and shaft to compress the coil spring, and by releasing the door, the resilient restoring force of the strong coil spring causes the sprocket, spindle, and door. Since it is equipped with a function to automatically return and close, even if it is a heavy door such as a heat-insulating door of a freezer, or even if the opening angle of the door is small, it can be securely returned with a strong turning force. There is an excellent effect to obtain.

Particularly, by adjusting and setting the position of the stopper in accordance with the accurate door closing position P ₁ , the position where the stopper automatically collides with the support and the stopper collides with the support base is the door closing position P ₁ . Therefore, the automatic return-closing operation of the accurate closing position is always performed without being affected by the size and weight of the door and the size of the opening angle. This is particularly advantageous in that the joints of both doors of the double doors are always perfectly aligned with each other, and the heat insulating and blocking effects are reliably maintained.

Although the automatic return means of the present invention requires a relatively large installation space, the present invention forms the protruding frame portion inside the cabinet (outside cabinet) by making the thickness of the door mounting frame larger than the wall. Since it is provided, the automatic return means can be installed in the space above the top plate of the outer protruding frame portion without any trouble, and its action and effect can be fully exhibited.

Even if the protruding frame portion of the mounting frame is provided so as to project inside the cabinet (outside the cabinet), a space for opening and closing the door is naturally required even in the case of the conventional door.
Since the installation space of the protruding frame portion is the same as the space, the installation space does not cause any trouble.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state in which an embodiment of the present invention is installed on a wall of a doorway portion of a refrigerator or the like.

FIG. 2 is a plan view of an embodiment of the present invention.

FIG. 3 is an explanatory view of the operation (closed door → opened door) of the embodiment of FIG.

FIG. 4 is a plan view showing a schematic configuration of another embodiment of the present invention.

FIG. 5 is a plan view showing a schematic configuration of another embodiment of the present invention.

[Explanation of symbols]

P ₁ Closed position P ₂ Opened position 1 Door 2 Support shaft 3 Sprocket 4 Chain 5 Shaft 6 Stopper nut 7 Support base 8 Spring receiving nut 9 Coil spring 10 Mounting frame 10a Projection frame part 11 Wall (wall panel) 12 Inside the room 13 Outer side 14 Tension roller 15 Guide shaft 16 Tension spring 17 Hydraulic cylinder 17a Rod

Claims (8)

[Claims] Claims: 1. A support shaft pivotally supporting a door so as to rotate in unison with the opening and closing movement of the door, a sprocket provided so as to rotate by rotation of the support shaft, and a sprocket hung around the sprocket in a substantially equal length. A door in the closed position, which consists of a chain with the specified set length, a shaft connected to the left and right ends of the chain, a support that inserts the shaft until the stopper collides, and a coil spring stretched between the rear ends of the shaft. When the support shaft and sprocket rotate due to pressing and opening due to human's force, etc., the chain and shaft are pulled to compress the coil spring, and when the door is released at the door open position, the chain spring and shaft stopper are restored by the coil spring restoring extension The automatic return means for the door, which is provided so that the door will return to its original position and the sprocket and support shaft will rotate to restore the door to its original position. 2. The thickness dimension of the mounting frame for mounting the door on the inside,
When the mounting frame is fitted to the wall by setting the thickness of the wall of the freezer such as the freezer to be larger than the wall around which the door is mounted, the part with the large thickness is inside or inside the wall. It is provided so as to form a protruding frame portion that protrudes outward, a door is attached to the inside of the protruding frame portion such that it can be opened and closed by a support shaft, and the upper end of the support shaft projects above the upper frame of the protruding frame portion. Attach a sprocket to the supported shaft, and hang a chain of the set length on the sprocket to the left and right approximately the same length,
A shaft is connected to the left and right ends of the chain, and the shaft is inserted into and supported by a support base fixed to the upper frame of the chain until the stopper collides, and a coil spring is provided between the support base and the rear end of the shaft. A means for automatically returning the door, which is installed by stretching. 3. The door according to claim 1, wherein the position of the stopper at the tip of the shaft is adjusted and moved in inverse proportion to the left and right to adjust and rotate the sprocket and the support shaft to adjust the angle of the door in the closed position. Automatic return means. 4. The automatic door returning means according to claim 1, further comprising adjusting the spring force of a coil spring stretched between the support base and the rear end of the shaft by adjusting the distance between the support base and the rear end of the shaft. 5. The automatic door returning mechanism according to claim 1, further comprising a chain, a timing belt, or other power transmission means wound around a sprocket. 6. The door according to claim 1, wherein tension rollers are provided on the left and right sides of the chain to suppress the slack of the left or right chain or the like that occurs when the sprocket pulls and rotates the right or left of the chain or the like. Automatic return means. 7. A guide shaft and a tension spring are connected to the left and right ends of a chain or the like, and the tension spring ends are fixedly attached to a part of the upper frame, and the guide shaft slides when pulled by the chain or the like when the door is opened. The tension spring expands as it moves, and when the door is released at the door open position, the restoring force of the tension spring pulls the guide shaft, chain, etc. to rotate the sprocket and support shaft to close and restore the door. A means for automatically returning the door according to claim 1. 8. A rod of a hydraulic cylinder or an air cylinder is connected to the left and right ends of a chain or the like, the rod is lightly extended by being pulled by the chain or the like when the door is opened, and the rod is hydraulically released when the door is released at the open position. The automatic return means for the door according to claim 1, wherein the automatic return means is provided so as to strongly retract and pull the chain or the like to restore the door to the closed state.