JP4530646B2 - Image reading device - Google Patents

Description

  The present invention provides an image provided with an urging unit that rotatably supports the document conveying unit with respect to the image reading unit, and for assisting the rotation of the document conveying unit, and a regulating unit that regulates the urging force of the urging unit. The present invention relates to a reading apparatus, and more particularly to a restricting means or a method for preventing damage to the apparatus main body.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine or a facsimile, a document pressing unit for pressing a document is disposed so as to be openable and closable above an image reading unit, and a document is placed and exchanged and maintenance for the image reading unit is performed. At this time, a mechanism that can open the document pressing portion is used. Recently, an automatic document feeder that sequentially conveys a plurality of documents to the image reading unit in the document pressing unit, and a device that functions as a document conveying unit are increasing. Such an image reading apparatus is shown in FIG. In the figure, reference numeral 1 denotes an image reading unit for reading a document image, and a contact glass 2 serving as a document table on which the document is set is provided on the upper surface. Reference numeral 3 denotes a document conveying unit that sequentially conveys a plurality of documents to the image reading unit 1, and is supported by the image reading unit 1 through the hinge unit 4 so as to be openable and closable in the arrow direction.

  FIG. 9 shows an enlarged view around the hinge portion of the image reading apparatus in FIG. In the figure, the document conveying section 3 is urged in the opening direction by a biasing means such as a hinge spring (not shown). The hinge section 4 includes a hinge base 4 a fixed to the image reading section 1 side, and the document conveying section 3. It is comprised from the hinge upper member 4b fixed to the side. The hinge base 4 a is fixed to a support 5 provided inside the image reading unit 1 by a connecting pin 6. Thereby, the rotational moment generated by the opening / closing operation of the document conveying unit 3 acts on the support column 5 and is dispersed, and does not directly act on the frame of the image reading unit 1, thereby suppressing deformation and breakage of the frame. Reference numeral 7 denotes an opening / closing detection button for detecting opening / closing of the document conveying section 3.

  In such an image reading apparatus, in particular, in the case of an apparatus capable of high-speed processing, the maximum amount of originals that can be stacked increases, so that the original conveying unit becomes larger and the weight increases accordingly. Therefore, an urging means such as a coil spring or a torsion bar that assists in opening the document conveying section is generally provided. This allows the user to easily perform the opening operation with a light force even in a heavy document transport unit. However, when the balance between the biasing means and the weight of the document conveying unit is not appropriate, a large force suddenly acts in the opening direction at the final stage of the operation of opening the document conveying unit, and the document conveying unit is moved to the image reading unit. In some cases, a large force is applied to the hinge portion that supports the frame, and the frame of the image reading portion may be distorted. For this reason, there is a problem in that the document conveying unit or the image reading unit main body and the components provided in the document conveying unit cause a positional deviation and adversely affect the image quality of the read image.

  Therefore, a method for adjusting the urging force by providing a regulating means that regulates the urging force of the urging means has been proposed. Patent Document 1 uses a torsion bar as the urging means and attaches the torsion bar as the regulating means. A method for adjusting the urging force of a torsion bar using an elastic member that exerts an urging force in a direction opposite to the urging force is disclosed. Further, in Patent Document 2, a metal stopper that regulates the maximum opening angle of the reading device is provided between the reading device (document conveying unit) and the recording device (image reading unit), and the opening angle is set to a predetermined value. An image forming apparatus provided with a resin-made locking mechanism that holds an angle is disclosed.

However, in the method of Patent Document 1, it is necessary to provide an arrangement space for an elastic member, which is a restricting means, in the document conveyance unit, and the document conveyance unit becomes large. Further, in the method of Patent Document 2, when the maximum opening angle of the document conveying portion that opens and closes via the hinge portion is restricted by a stopper, the urging force of the urging means is increased particularly when the weight of the document conveying portion is heavy. Therefore, when the opening angle of the document conveying unit is maximized, the rotation moment of the document conveying unit is directly applied to the stopper or the image reading unit that supports the stopper, leading to deformation or breakage of the stopper or the image reading unit itself. There was a problem.
JP 2002-330243 A JP 2001-296710 A

  In view of the above problems, the present invention restricts the urging force of the urging means for assisting the opening of the heavy document conveying section by the regulating means, and can prevent deformation and breakage of the regulating means and the apparatus main body. The purpose is to provide.

In order to achieve the above object, the present invention provides a document table on which a document is placed, a document conveyance unit that is provided above the document table and conveys a document, and a document table that is provided below the document table. An image reading unit for reading a document image conveyed by the document conveying unit; a hinge base fixed to the image reading unit; and a hinge upper member fixed to the document conveying unit; And a biasing means for biasing the document conveying portion in an opening direction, and one end of the document conveying portion can be rotated in the opening / closing direction of the document conveying portion. And a restricting means for restricting the urging force of the urging means when the document conveying part is opened. In the image reading apparatus, the restriction means is the clerk. A locking mechanism that holds the document conveying section in a fully opened range at a predetermined angle by being sandwiched between a stopper provided on the back surface of the hinge base and the back surface of the hinge base. , from a state in which the lock mechanism is operated and the predetermined load is applied in the direction to open the document feeder, and the rear end portion of the hinge upper member presses the restricting means the locking portion The lock mechanism is released by releasing the engagement with the stopper.

According to the present invention, in the image forming apparatus configured as described above, the hinge base and the hinge upper member are rotatably connected to the hinge base about a first fulcrum and centered on the second fulcrum. A hinge lower member rotatably connected to the hinge upper member is provided, and a predetermined load is applied to the first fulcrum in a direction in which the document conveying unit is closed from a state where the lock mechanism is operated. When applied, the hinge upper member rotates about the second fulcrum and moves away from the hinge lower member, whereby the hinge portion is refracted in two stages .

According to the present invention, in the image forming apparatus having the above-described configuration, a plurality of the hinge lower members are provided, and the hinge lower members are sequentially connected by different rotation fulcrums, and the lock mechanism is activated, The hinge portion is refracted in three or more stages when a predetermined load is applied to the rotation fulcrum of the hinge portion in a direction in which the document conveying portion is closed.

According to the first configuration of the present invention, even when a large urging force is suddenly applied by the hinge spring when the document conveying portion is opened, the stopper provided on the back surface of the hinge base is the locking portion of the restricting means. And a hinge mechanism between the hinge base and the back surface of the hinge base to operate the lock mechanism for holding the document conveying section at a predetermined angle, thereby preventing the hinge section or the apparatus body from being deformed or damaged with a simple structure, and the lock mechanism. When There predetermined load is applied to the open direction while operating, by the locking mechanism is released the rear end portion of the hinge upper member presses the regulating means, also act even greater force in the opening direction The deformation and breakage of the regulating means can be prevented.

According to the second configuration of the present invention, in the image forming apparatus having the first configuration, the hinge portion is configured by a hinge base, a hinge upper member, and a hinge lower member, and the hinge upper member and the hinge base are , it is rotatably connected to the hinge lower member about the different fulcrum respectively, since the hinge portion is a Rukoto be refracted in two stages, the breakage of the hinge portion to reduce the load applied to the hinge portion with a simpler structure Can be prevented . Further, even when a thick original such as a book original is placed, the original can be securely attached to the contact glass.

According to the third configuration of the present invention, in the image forming apparatus of the second configuration, a plurality of hinge lower members are provided, and the hinge lower members are sequentially connected by different rotation fulcrums so that the hinge portion is a document. By adopting a structure that refracts in three steps or more in the direction in which the conveying unit is closed, a load applied to the hinge unit can be further reduced, and a thick original such as a book original can be more closely attached.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a rear perspective view of the hinge portion 4 used in the present invention, and FIG. 2 is a side view of the hinge portion 4. FIG. 3 is a front view of the hinge portion 4 as viewed from the direction of arrow A in FIG. As shown in the figure, the hinge portion 4 is composed of a hinge base 4a, a hinge upper member 4b, and a hinge lower member 4c. A pin hole (not shown) for inserting a connection pin is provided on the bottom surface of the hinge base 4a, and the hinge base 4a is fixed to a support in the image reading unit 1 by the connection pin as shown in FIG.

  The hinge base 4a and the hinge lower member 4c are connected to be pivotable about a fulcrum 8a, and the hinge upper member 4b and the hinge lower member 4c are connected to be rotatable about a fulcrum 8b. A plurality of screw holes 9 are provided on the upper surface of the hinge upper member 4b, and the hinge upper member 4b is screwed to a frame that supports the document conveying portion. The rear end portion of the hinge upper member 4b extends longer than the rear end portion 10 of the hinge lower member 4c to form a protrusion 11, and the rear end portion 10 of the hinge lower member 4c corresponds to the protrusion of the hinge upper member. The portion to be bent is formed by bending 90 ° inward. A stopper 12 for locking the rear end portion 10 of the hinge lower member 4c is fixed to the back surface of the hinge base 4a. The locking surface 12a of the stopper 12 is provided so as to be inclined at a predetermined angle with respect to the back surface of the hinge base 4a, and the opening angle of the hinge portion 4 is restricted when the rear end portion 10 abuts. That is, the opening angle of the hinge portion 4 in a state where the rear end portion 10 is in contact with the locking surface 12a is the maximum opening angle of the document conveying portion.

  Further, as shown in FIG. 3, two hinge springs 13 for energizing the document conveying portion in the opening direction are accommodated in the hinge lower member 4c. A resin spring holding member 14 holds the hinge spring 13 inside the hinge lower member 4 c and is provided so as to cover the upper and lower sides of the hinge spring 13. The biasing force of the hinge spring 13 is appropriately selected according to the weight of the document conveying unit. A resin cam 15 for smoothly opening and closing the hinge portion 4 is provided in the hinge base 4a. Reference numeral 16 denotes an attachment portion for fixing the hinge upper member 4b to the document conveying portion, and 17 denotes a support portion for supporting the spring holding member 14 within the hinge lower member 4c.

  When the opening / closing operation of the document conveying unit is performed, the hinge unit 4 normally rotates around the fulcrum 8a, but a thick document such as a book (hereinafter referred to as a book document) is placed on the contact glass of the image reading unit. When the closing operation is performed, as shown in FIG. 2, the hinge upper member 4b and the hinge lower member 4c rotate about the fulcrum 8b, and the hinge portion 4 is refracted in two stages. Although it is possible to directly connect the hinge base 4a and the hinge upper member 4b without providing the hinge lower member 4c, the hinge portion can also be provided by placing the hinge lower member 4c even when a thick original is placed. This is more preferable because an excessive load is not applied to the fulcrum 8a of 4 and the original can be securely pressed and brought into close contact with the contact glass. In this example, one hinge lower member 4c is provided. However, if a plurality of hinge lower members 4c are provided and sequentially connected at different rotation fulcrums, the entire hinge portion 4 is refracted in multiple stages. The load applied to the fulcrum 8a can be further reduced, and the original can be more closely attached to the contact glass.

  Next, a restricting unit that restricts the urging force and a lock mechanism that holds the document conveying unit at a predetermined angle will be described. FIG. 4 is a block diagram showing the structure around the hinge portion when the lock mechanism is activated in the image reading apparatus of the present invention. In the figure, reference numeral 18 denotes a metal restricting means having an L-shaped side surface for restricting the attachment force of the hinge spring. Reference numeral 19 denotes a frame that supports a document conveying portion (not shown), and rotates around the hinge portion 4 together with the document conveying portion. One end of the restricting means 18 is supported by the frame 19 so as to be rotatable about the fulcrum 8c. A locking bar 20 is provided at the other end of the restricting means 18.

  The structure of the regulating means used in the present invention is shown in FIG. FIG. 5A is a side view of the restricting means 18, and FIG. 5B is a front view of the restricting means 18 as viewed from the direction of the arrow in FIG. As shown in the figure, the restricting means 18 has a shape in which a rectangular metal plate is bent into an L-shape, and side portions 18a and 18b are symmetrical on the left and right ends of each surface forming the L-shape. Is provided. Pin holes 18c are provided symmetrically on the side surface portion 18a provided on one side of the L-shape (upper side in the figure), and can be rotated up and down by a pin (not shown) on the frame 19 that supports the document conveying portion. Supported. Moreover, the latching bar 20 is fixed to the side surface part 18b provided in the other surface (lower side of the figure) in a bridge shape. In addition, the shape of the control means 18 is not limited to this, It can change suitably in the range of the objective of this invention.

  Suppose that the original conveying unit is operated from the fully closed state in the opening direction to the angle shown in FIG. At this time, when the locking bar 20 is sandwiched between the locking surface 12a of the stopper 12 and the back surface of the hinge base 4a, the rotation of the fulcrum 8a is restricted, and the document conveying section is held at that angle. Thus, even when a large biasing force is suddenly applied by the hinge spring when opening the document conveying portion, the lock mechanism operates before being opened to the maximum opening angle, so that the fulcrum of the hinge portion 4 or It can be prevented that an excessive load is applied to the stopper 12 and the hinge portion 4 or the stopper 12 is deformed or broken. Further, since the document conveying section can be held at a predetermined angle, the work efficiency when setting or exchanging documents is improved.

  Next, the unlocking operation of the lock mechanism will be described. When a predetermined load is further applied in the opening direction of the document conveying portion from the state of FIG. 4, as shown in FIG. 6, the frame 19 rotates together with the document conveying portion in the direction of arrow A around the fulcrum 8a, thereby The hinge upper member 4b fixed to 19 also rotates in the arrow A direction. At the same time, the protrusion 11 provided at the rear part of the hinge upper member 4b is lowered, and the lower side surface portion (18b in FIG. 5) of the restricting means 18 is pushed rearward (rightward in FIG. 6). The means 18 rotates in the direction of arrow B, the locking bar 20 is detached from the locking surface 12a, and the locking mechanism is released. The document conveying section with the lock mechanism released is rotated in a direction in which the opening angle is further expanded, and is held at the maximum opening angle by the rear end portion 10 of the hinge lower member 4c coming into contact with the locking surface 12a.

  As a result, when a predetermined load is further applied in the opening direction from the operating state of the locking mechanism, the locking mechanism is automatically released, so that the parts such as the hinge portion 4 and the regulating means 18 or the deformation of the image forming apparatus main body can be changed. Breakage can be prevented. On the other hand, when a load is applied in the closing direction of the document conveying unit from the state of FIG. 4, the restricting means 18 is lifted upward together with the frame 19, so that the locking bar 20 is detached from the locking surface 12a and locked. The mechanism is released. Therefore, the user can fully close the document conveying unit with a relatively small force using the weight of the document conveying unit.

  Further, when the book document is placed on the contact glass of the image reading unit and the closing operation is performed in the lock mechanism operating state, the hinge upper member 4b and the hinge lower member 4c are centered on the fulcrum 8b as shown in FIG. Rotating in the direction of arrow A, the hinge part 4 is refracted in two stages at the fulcrums 8a and 8b. As a result, even if a closing force is applied to the document conveying unit when the book document is placed, an excessive load is not applied to the fulcrum 8a of the hinge unit 4, and the book document can be securely pressed. It becomes. Further, the protrusion 11 provided at the rear part of the hinge upper member 4b rises and the upper side surface portion (18a in FIG. 5) of the restricting means 18 is pushed upward (upward in FIG. 7). Rotate in B direction. Then, the locking bar 20 is detached from the locking surface 12a, the lock mechanism is released, and the lock mechanism is prevented from being damaged.

  According to the above configuration, even if a load exceeding the limit is applied to the document conveying unit, the frame of the image reading apparatus 1 is damaged by damage to parts such as the hinge unit 4, the stopper 12, or the regulating unit 18. Since there is no deformation, the number of replacement members is reduced and the maintainability is improved. Further, if the restricting means 18 is made of a metal plate that is softer or thinner than the frame of the hinge part 4 or the image reading part 1 and only the restricting means 18 is damaged, the hinge part 4 or the image reading part 1 Can be more effectively prevented.

The present invention provides a document table on which a document is placed, a document conveyance unit that is provided above the document table and conveys a document, and a document image that is provided at the bottom of the document table and is conveyed on the document table or by the document conveyance unit. A hinge having an image reading unit to be read, a hinge base fixed to the image reading unit, and a hinge upper member fixed to the document conveying unit, and rotatably holding the document conveying unit with respect to the image reading unit And an urging means for urging the document conveying portion in the opening direction, and one end supported on the document conveying portion so as to be rotatable in the opening / closing direction of the document conveying portion, and a locking portion for locking to the hinge portion on the other end And a restricting means for restricting the urging force of the urging means when the document conveying section is opened. In the image reading apparatus, the restricting section is provided on the back surface of the hinge base. Is sandwiched between the stopper and the back of the hinge base And by the document conveying unit includes a locking mechanism for holding at a predetermined angle opened state within the entire opening range, from the state in which the lock mechanism is operating, it toward the predetermined load to open the document conveying unit Is added, the rear end portion of the upper hinge member presses the restricting means to release the engagement between the engagement portion and the stopper, thereby releasing the lock mechanism.

As a result, the locking mechanism is operated before the locking portion of the restricting means is released by the stopper provided on the back surface of the hinge portion, so that the maximum opening angle is released. When a predetermined load is applied in the direction in which the transport unit is opened, the restricting means is pressed against the rear end portion of the upper hinge member, and the latching portion and the stopper are unlocked. In addition, the lock mechanism can be prevented from being easily damaged, and even if the lock mechanism is damaged, it can be repaired only by replacing the restricting means, and the maintenance work is easy and low-cost. In addition, when the original is placed or replaced, the working efficiency is improved by the lock mechanism.

Further, the hinge base and the hinge upper member are provided with one or more hinge lower members that are rotatably connected at different fulcrums, and the hinge portion is refracted in two or more steps in the direction of closing the document conveying portion. Thus, even when a thick original such as a book original is placed, it is possible to reduce the load applied to the hinge part in the closing direction of the original conveying part and prevent the hinge part or the apparatus main body from being deformed or damaged.

These are the back perspective views of the hinge part used for this invention. FIG. 4 is a side view of the hinge portion. These are front views of a hinge part. FIG. 4 is a schematic view showing a configuration around a hinge portion when a lock mechanism is operated in the image reading apparatus of the present invention. These are the schematic diagrams which show an example of the control means used for this invention. FIG. 6 is a schematic diagram illustrating a lock mechanism releasing operation when a load is applied in the opening direction of the document conveying unit. FIG. 5 is a schematic diagram showing a lock mechanism releasing operation when a book document is placed and a load is applied in the closing direction of the document conveying unit. FIG. 1 is a schematic diagram illustrating a configuration of a conventional image forming apparatus. These are the block diagrams of the surroundings of the hinge part of the conventional image forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image reading part 2 Contact glass 3 Document conveying part 4 Hinge part 4a Hinge base 4b Hinge upper member 4c Hinge lower member 5 Post 8a-8c Support point 10 Rear end part 11 Protrusion part 12 Stopper 12a Locking surface 13 Hinge spring 14 Spring holding Member 15 cam 18 restricting means 19 frame 20 locking bar

Claims (3)

An original table on which an original is placed;
A document transport unit provided on an upper part of the document table for transporting a document;
An image reading unit provided at a lower portion of the document table for reading a document image conveyed on the document table or by the document conveyance unit;
A hinge base having a hinge base fixed to the image reading unit and a hinge upper member fixed to the document conveying unit, the hinge unit rotatably holding the document conveying unit with respect to the image reading unit; ,
Urging means for urging the document conveying section in the opening direction;
One end is rotatably supported by the document conveying unit in the opening / closing direction of the document conveying unit, and the other end is provided with a latching unit that latches to the hinge unit, and when the document conveying unit is opened, the An image reading apparatus comprising: a regulating unit that regulates a biasing force of the biasing unit;
In the state where the restricting portion is sandwiched between a stopper provided on the back surface of the hinge base and the back surface of the hinge base, the document conveying portion is opened at a predetermined angle within a fully open range. includes a locking mechanism for holding, from a state where the lock mechanism is operated and the predetermined load is applied in the direction to open the document feeder, the rear end portion of said hinge upper member is the regulating means The image reading apparatus according to claim 1, wherein the locking mechanism is released by releasing the locking between the locking portion and the stopper. A hinge connected between the hinge base and the upper hinge member so as to be rotatable about the first fulcrum and rotatably connected to the upper hinge member about the second fulcrum. A lower member is provided,
When a predetermined load is applied to the first fulcrum in a direction in which the document conveying unit is closed from the state in which the lock mechanism is activated, the upper hinge member rotates about the second fulcrum and the hinge The image reading apparatus according to claim 1, wherein the hinge portion is refracted in two stages by being separated from the lower member. A plurality of the hinge lower members are provided, and the hinge lower members are sequentially connected by different rotation fulcrums, and the document conveying unit is closed to the rotation fulcrum of the hinge unit from the state where the lock mechanism is operating. The image reading apparatus according to claim 2 , wherein when a predetermined load is applied in a direction, the hinge portion is refracted in three or more stages.

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