KR20070067673A - Hinge unit and image forming apparatus having the same - Google Patents

Abstract

A hinge unit and an image forming apparatus with the hinge unit are provided to vary the force of an elastic member according to an opening/closing angle of a cover such that a user easily opens and closes the cover. A hinge unit(100) includes a lower frame(110), an upper frame(120), a first elastic member(131), and a second elastic member(132). The lower frame is combined with a scan unit of an image forming apparatus. The upper frame is connected to the lower frame through a hinge shaft(P) and combined with a cover of the image forming apparatus. The first and second elastic members are arranged in the upper frame and have different elasticity coefficients. When the cover is turned to the scan unit, the first elastic member is moved and then the second elastic member is moved.

Description

Hinge Unit and Image Forming Apparatus Having The Same

1 is an external view of a general multifunction device,

2 is a cross-sectional configuration diagram of a conventional hinge unit,

3 is a perspective view of the hinge unit of the present invention,

4 is an exploded perspective view of FIG. 3;

5 is a side cross-sectional view of FIG.

6 is a front view showing a detailed structure of the elastic members of FIG.

7 is a configuration diagram of another hinge unit of the present invention,

8a to 8b is an operating state diagram for the hinge unit of FIG.

9 is a graph showing the relationship of the load according to the opening and closing angle of the cover for the hinge unit of the present invention.

<Description of the symbols for the main parts of the drawings>

100, 200: hinge unit 110: lower frame

120: upper frame 121, 122: first, second movable holder

123: fixed holder 125: connecting member

131 and 132: elastic member P: hinge shaft

The present invention relates to a hinge unit and an image forming apparatus having the same. More particularly, the hinge unit and the image forming apparatus including the same may be used to smoothly open and close the cover by differently applying elastic force according to the opening and closing angle of the cover. It is about.

In general, an image forming apparatus having an original scanning function such as a copying machine, a scanner, a multifunction printer, or the like is a device that scans a document and stores the scanned image as data or outputs it on paper.

Fig. 1 shows an example of a general multifunction apparatus which is one of such image forming apparatuses. Referring to the drawings, the multifunction apparatus includes an original scanning unit 2 provided in the main body 1 of the apparatus for reading an original, a cover 3 covering an original placed on the scanning unit 2, and a scanning unit 2. And a hinge unit 10 connecting the cover 3. The cover 3 may further be provided with an automatic document feeder 4 for automatically supplying a plurality of originals to the area of the scanning unit 2. In a high-speed multifunction printer or copier, not a small home multifunction printer, an automatic two-sided paper feeder is installed on the cover. The cover 3 of such a multifunction device is quite heavy for the user to open and close.

In general, the opening and closing angle of the cover of the image forming apparatus is usually about 0 to 80 degrees. The moment caused by the rotation of the cover at each angle does not increase constantly. When the cover is closed, the moment is increased close to 0 degrees, the elastic force to achieve an equilibrium is increased. Therefore, it is difficult to maintain the moment equilibrium according to the opening angle of the cover with only one spring. Typically, one spring is installed in the hinge unit, but two springs may be installed in parallel when a large force is required. However, when one or two springs are used in parallel, there is no freedom in design, and the overspec springs must be selected to apply the spring force to all opening and closing angles. In this case, the user feels poor quality when opening and closing the cover. Therefore, the spring design of the hinge unit connecting the cover and the scan unit of the main body is important in order to allow the user to open and close the cover smoothly with little force when opening and closing the cover for scanning or copying.

2 shows a cross-sectional configuration of a hinge unit mounted in a conventional image forming apparatus. The hinge unit of FIG. 2 is a technique disclosed in Japanese Patent Laid-Open No. 2003-129739, which is a hinge unit 10 in which two springs 11 and 12 are connected in series.

Referring to the drawings, the hinge unit 10 includes: a cam base 30 coupled to the cover 3; A plunger 21 accommodated in a hinge housing 20 to reciprocate freely and having an inclined surface 22; First and second springs 11 and 12 received in the hinge housing 20 and pressing the plunger 21; And first and second cams 31 and 32 which rotate simultaneously with the cam base 30 and contact the inclined surface 22. In the hinge unit 10, a drag acting as a reaction from the first cam 31 is applied to the inclined surface 22 of the plunger 21 in the direction of a common normal of the contact point, and the drag force causes the plunger 21 to be attached to the first cam 31. It acts as a moment of inclination to the rear of the rotational direction (arrow direction) to deviate from, increasing torque in the direction to open around the hinge axis P. Thereby, the force which pops up the cover 3 can fully be obtained, and the deformation | transformation of the cam base 30 and the plunger 21 can be prevented. However, the hinge unit 10 causes abrasion between the first and second cams 31 and 32 and the inclined surface 22 of the plunger 21, and the user still applies a large force, especially when opening and closing the heavy cover. The cover does not work smoothly.

An object of the present invention is to provide a hinge unit that allows the user to open and close the cover smoothly with a small force when opening and closing the cover by differently acting the force of the elastic member according to the opening and closing angle of the cover in a general image forming apparatus.

Another object of the present invention is to provide an image forming apparatus provided with such a hinge unit.

Hinge unit of the present invention for achieving the above object, the lower frame is coupled to the scan unit of the main body; An upper frame connected to the lower frame through a hinge shaft and coupled to a cover; And first and second elastic members having different modulus of elasticity installed in series in the upper frame, wherein the first elastic member is displaced when the cover is rotated toward the scan unit. , The second elastic member is displaced.

The upper frame is preferably provided at one end thereof, the fixing holder for holding the first elastic member; A first movable holder installed to face the fixed holder, the second elastic member being positioned and moving along the longitudinal direction of the upper frame; And a second movable holder positioned between the first elastic member and the second elastic member to move along the longitudinal direction of the upper frame.

The upper frame may include a guide rail for guiding the first and second movable holders to slide in the longitudinal direction of the upper frame.

The upper frame may further include a fixing member so that the fixing holder is not pushed outward.

The lower frame is preferably provided with a link fixed to the front of the hinge shaft in contact with the first movable holder.

The fixed holder and the second movable holder may be provided with sidewalls around one or both sides facing each other. The side wall of the fixing holder may extend downward. Preferably, the second movable holder has sidewalls extending upward and / or downward. The total height of the sidewalls is preferably equal to or longer than the height of the first elastic member completely compressed. Each holder may be provided with mounting portions for placing the first and second elastic members.

Preferably, the first elastic member and the second elastic member are springs, and the spring constant K1 of the first elastic member is smaller than the spring constant K2 of the second elastic member.

In addition, the image forming apparatus of the present invention includes a main body including a scan unit; And a cover connected by the scan unit of the main body and the hinge unit.

Hereinafter, exemplary embodiments of the hinge unit and the image forming apparatus having the same will be described in detail with reference to the accompanying drawings.

3 to 6 is an example of the hinge unit of the present invention, Figure 3 is a coupling view, Figure 4 is an exploded perspective view, Figure 5 is a side cross-sectional view, Figure 6 shows a detailed structure of the elastic member One frontal view. Referring to the drawings, the hinge unit 100 of the present invention includes a lower frame 110; And an upper frame 120 connected through the lower frame 110 and the hinge shaft P.

The lower frame 110 is coupled to the scan unit 2 mounted to the main body 1 (see FIG. 1) of the image forming apparatus. The lower frame 110 may have a fastening hole 114a formed on the bottom surface 114 to be coupled to the scan unit 2 by a fastening member (not shown). The lower frame 110 is provided with a hinge shaft P through a hole 116a formed at an upper end thereof, and a link 112 is fixedly installed through a hole 112a formed in front of the hinge shaft P. The hinge axis and the link may each have a round bar shape. The link 112 is in contact with the first movable holder 121 of the upper frame 120, the first movable holder 121 is caught by the link 112 and is pushed to the upper portion of the upper frame 120.

The upper frame 120 is coupled to the cover 3 of the image forming apparatus, and is connected to the lower frame 110 by the hinge shaft P through the hole 120a on one side. The upper frame 120 may be fixed to the cover 3 through the connection member 125.

The first and second elastic members 131 and 132 are disposed in series in the upper frame 120. In the present invention, the number of elastic members is not limited, but the two elastic members 131 and 132 may be disposed in series.

The upper frame 120 has a fixed holder 123 is installed at one upper end thereof, and a first movable holder 121 is installed at the other lower end thereof opposite to the fixed holder 123. The fixed holder 123 supports the first elastic member 131 so as not to be pushed. Fixing members 126a and 126b may be provided on the upper frame 120 or the connecting member 125 so that the fixing holder 123 is not pushed outward.

First and second elastic members 131 and 132 are disposed in series between the fixed holder 123 and the first movable holder 121. The first movable holder 121 may be provided with a mounting portion 121e formed of sidewalls of the bottom surface of the second elastic member 132. The second elastic member 132 may be fixed to the first movable holder 121 by the mounting portion 121e of the first movable holder 121. The mounting portion as described above may also be formed in the fixed holder 123.

In addition, a second movable holder 122 is provided between the first elastic member 131 and the second elastic member 132.

The upper frame 120 may be provided with guide rails 124a and 124b at both sides thereof such that the first movable holder 121 and the second movable holder 122 slide along the longitudinal direction thereof. . Each of the first and second movable holders 121 and 122 is formed with guide grooves 121a, 121b, 122a and 122b, and the first and second movable holders 121 and 122 are guided by the guide grooves. It can be moved smoothly along the rails (124a, 124b).

The hinge unit 100 in the figure illustrates a spring as the first elastic member 131 and the second elastic member 132. In the hinge unit of the present invention, the spring constant K1 of the first elastic member 131 is the second elastic member 132 so that the first elastic member 131 is operated first and then the second elastic member 132 is operated. It is preferable that it is smaller than the spring constant K2. To further ensure this operation, side walls may be provided in each holder 221-223. 7 shows a hinge unit according to such an embodiment.

7 is a block diagram of another hinge unit of the present invention. Referring to the drawings, the hinge unit 200 is the same as the hinge unit 100 of FIG. 3 except that sidewalls are formed in the holders 221-223, and thus redundant descriptions thereof will be omitted. For convenience of description, FIG. 7 shows only the holders 221-223 and the elastic members 131 and 132 inherent in the upper frame.

The hinge unit 200 includes sidewalls on one or both sides of the second movable holder 221 and the fixed holder 223 facing each other. The second movable holder 222 and the fixed holder 223 shown in the drawing show a case in which side walls 222c and 223c are formed to face each other along their respective circumferences. The total height of the side wall 223c of the fixed holder 223 and the side wall 222c of the second movable holder 222 may be equal to or longer than the height of the first elastic member 131 completely compressed. This is to allow the first elastic member 131 to operate first and then the second elastic member 132 to operate. That is, when the first elastic member 131 is compressed, the first elastic member 131 is no longer operated by the contact between the side wall 222c of the second movable holder 222 and the side wall 223c of the fixed holder 223. The second elastic member 132 is not operated.

The side walls 221c-223c of each holder 221-223 provide mounting portions 221e-223e for fixing the elastic members 131, 132. The second movable holder 222 may be provided with another sidewall 222 ′ c below.

These hinge units may be attached to various devices having a cover, but in the present invention, the main body 1 including the scan unit and the cover 3 hinged to the scan unit 2 of the main body 1 may be included. Applicable to an image forming apparatus. In particular, the hinge units of the present invention are more suitable for an image forming apparatus in which a cover is relatively heavy because an automatic sheet feeder (ADF, 4, see Fig. 1) is mounted on the top of the cover.

Hereinafter, the operation and effect of the hinge unit mounted on the image forming apparatus of the present invention will be described in detail with reference to the accompanying drawings.

8A to 8D are operation state diagrams of the hinge unit mounted to the image forming apparatus of the present invention. For convenience of description, only the respective holders 221-223 and two springs 131 and 132 are shown. will be. Of course, the upper frame of the hinge unit 200 is fixed to the cover of the image forming apparatus, the lower frame will be attached to the scan unit of the main body will be fixed.

In general, the opening and closing angle of the cover of the image forming apparatus is usually about 0 to 80 degrees. The moment caused by the rotation of the cover at each angle does not increase constantly. As the cover is closed, the moment is increased as it is close to 0 degrees, the elastic force to achieve an equilibrium is increased. The hinge unit of FIG. 8 according to the present embodiment may arrange two springs in series to maintain moment equilibrium according to the opening and closing angle of the cover.

In the present embodiment, when the spring constant of the first spring 131 is K1 and the spring constant of the second spring 132 is K2, the first spring 131 uses a spring smaller than K2. Displacement is made before the second spring 132.

8A illustrates that no force is applied to the upper frame or the cover. When the cover is closed in the state shown in FIG. 8A, the second movable holder 222 and the fixed holder 223 start to push down, and the upper frame 120 rotates around the hinge axis (FIG. 8B). The cover causes a large moment about the hinge axis P by its own weight, and an elastic force corresponding to this moment is generated by the link 112 of FIG. 3. The link 112 prevents the first movable holder 221 from being pushed, thereby preventing the cover from being closed. Since the first spring 131 and the second spring 132 are arranged in series in the same state as in FIG. 8B, the total spring constant K_tot will be (K1 × K2) / (K1 + K2).

Next, when the cover is closed for a predetermined angle or more, as shown in FIG. 8C, the first spring 131 is completely compressed, and the sidewalls 223c of the fixed holder 223 and the sidewalls of the second movable holder 222 are closed. 222c) is contacted. Therefore, the first spring 131 no longer serves as a spring, and as shown in FIG. 8D, elastic force is generated only by the second spring 132. In the state shown in FIG. 8D, the total spring constant K_tot will be K1.

As described above, in the hinge unit of the present invention, a weak first spring acts before a predetermined angle, and a larger second spring acts at a predetermined angle or more to offset the moment due to the cover weight. 9 shows the elastic force of the hinge unit according to the opening and closing angle of the cover.

9 is a graph showing a relationship of loads according to opening and closing angles of a cover for the hinge unit in which two springs are arranged in series. As shown in FIG. 9, according to the hinge unit of the present invention, a small force is required for the cover when the cover starts to be closed, that is, when the cover has a large opening and closing angle. However, when the cover is almost closed, that is, the opening and closing angle of the cover can be seen that a large force should be applied to the cover.

Therefore, in the present invention, by designing a spring by appropriately selecting the spring constant of each of the elastic members of the hinge unit, it is possible to prevent the cover from being automatically closed by its own weight, so as not to inconvenience the user to open and close when scanning or copying do.

As described above, according to the hinge unit of the present invention, by connecting the plurality of elastic members in series, a small elastic force is applied to a certain cover opening and closing angle, and a larger elastic force is applied to the cover opening and closing angle. In response to the moment, the quality of the hinge unit felt when the user opens and closes the cover is improved.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications may be made by those skilled in the art. For example, a plurality of elastic members having different spring constants in addition to the first and second elastic members may be provided between the fixed holder and the first movable holder, and movable holders for placing the plurality of elastic members. Therefore, the true technical protection scope of the present invention will be defined by the appended claims.

Claims (20)

A lower frame coupled to the scan unit of the main body; An upper frame connected to the lower frame through a hinge shaft and coupled to a cover; And And first and second elastic members having different modulus of elasticity installed in series in the upper frame. The upper frame, A fixing holder installed at one end thereof and for holding the first elastic member; A first movable holder installed to face the fixed holder, the second elastic member being positioned and moving along the longitudinal direction of the upper frame; And And a second movable holder positioned between the first elastic member and the second elastic member to move along the longitudinal direction of the upper frame. And the second elastic member is displaced when the cover is rotated toward the scan unit, and then the second elastic member is displaced. The hinge unit according to claim 1, wherein the upper frame includes a guide rail for guiding the first and second movable holders to slide in the longitudinal direction of the upper frame. The hinge unit of claim 1, wherein the upper frame further includes a fixing member to prevent the fixing holder from being pushed outward. The hinge unit according to claim 1, wherein the lower frame includes a link fixed to the front of the hinge shaft so as to contact the first movable holder. The hinge unit according to claim 1, wherein the fixed holder and the second movable holder are provided with sidewalls around one or both sides facing each other. 6. The hinge unit according to claim 5, wherein the fixing holder has a side wall extending downward. 6. The hinge unit according to claim 5, wherein the second movable holder has side walls extending upward and / or downward. 6. The hinge unit of claim 5, wherein the total height of the sidewalls is equal to or longer than the height of which the first elastic member is fully compressed. The hinge of claim 1, wherein the first elastic member and the second elastic member are springs, and the spring constant K1 of the first elastic member is smaller than the spring constant K2 of the second elastic member. unit. A lower frame having a link; An upper frame connected to the lower frame through a hinge shaft; A fixed holder fixed to one end of the upper frame; A first movable holder disposed in the upper frame opposite the fixed holder and in contact with the link; First and second elastic members having different modulus of elasticity disposed in series between the fixed holder and the first movable holder; And And a second movable holder positioned between the first and second elastic members so as to slide along the guide member for guiding the movement of the first movable holder. 11. The hinge unit of claim 10, wherein the upper frame further includes a fixing member to prevent the fixing holder from being pushed outward. The hinge unit according to claim 10, wherein the fixed holder and the second movable holder are provided with sidewalls around one or both sides facing each other. 13. The hinge unit of claim 12, wherein the fixing holder has a side wall extending downwardly. 13. The hinge unit according to claim 12, wherein the second movable holder has sidewalls extending upwardly and / or downwardly. 13. The hinge unit of claim 12, wherein a total height of the sidewalls is equal to or longer than a height at which the first elastic member is fully compressed. The hinge of claim 10, wherein the first elastic member and the second elastic member are springs, and the spring constant K1 of the first elastic member is smaller than the spring constant K2 of the second elastic member. unit. The hinge unit according to claim 10, wherein the first elastic member is operated before the second elastic member when the upper frame rotates toward the lower frame. The method of claim 10, wherein a plurality of elastic members having different spring constants in addition to the first and second elastic members between the fixed holder and the first movable holder, and a plurality of movable holders for placing the plurality of elastic members Hinge unit, characterized in that the additional installation. A main body including a scan unit; And And a cover connected by the scan unit and the hinge unit of the main body. The hinge unit, A lower frame coupled to the scan unit; An upper frame connected to the lower frame through a hinge shaft and coupled to a cover; And And first and second elastic members having different modulus of elasticity installed in series in the upper frame. And the second elastic member is displaced when the cover is rotated toward the scan unit, and then the second elastic member is displaced. 20. The image according to claim 19, wherein the first elastic member and the second elastic member are springs, and the spring constant K1 of the first elastic member is smaller than the spring constant K2 of the second elastic member. Forming device.

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