JP2013184377A - Locking mechanism for cassette and cover member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a locking mechanism for a cassette and a cover which can reduce the number of component and detect that each of the cassette and the cover is in a locked state.SOLUTION: A common locking member 3 locks an ink ribbon cassette 1 attached to and detached from an image forming apparatus and a cover member 2 that is freely opened and closed to cover the ink ribbon cassette. The locking member 3 is operable in a first moving direction and a second moving direction, each of which is intersected, and unlocks the cover member 2 corresponding to in the first moving direction and the ink ribbon cassette 1 corresponding to in the second moving direction. Moreover, an optical sensor 4 detects the existence of the ink ribbon cassette 4 and detects whether the cover member 2 and the ink ribbon cassette 1 are normally locked.

Description

  The present invention relates to a lock mechanism that regulates the position when a cassette containing ink, paper, or the like is loaded into an image forming apparatus, and more particularly, a lock that detachably locks the cassette and a lid member that covers the cassette can be freely opened and closed. The present invention relates to a lock mechanism that shares a lock that is locked to the door.

  2. Description of the Related Art Conventionally, as an image forming apparatus for home use, a configuration in which various inks are stored in a dedicated cassette and ink replacement is easily realized by inserting and removing the cassette has been widely used. This is a mechanism in which a lock mechanism is provided in the image forming apparatus and the cassette loaded in the apparatus is regulated at an arbitrary position, and the cassette can be taken out by the unlocking operation. Detection means for detecting the presence or absence of a cassette is disposed inside the apparatus, and is used to determine whether or not the cassette is correctly loaded in the apparatus and is ready for printing.

  Furthermore, in this type of image forming apparatus that is assumed to be used by an unspecified number of users, a lid member that covers the cassette is provided as an exterior cover from the viewpoint of fewer restrictions on the external design and safety and prevention of erroneous operation. Is common. This lid member is configured to be openable and closable, and is opened only when the cassette is inserted and removed, and the others are held closed. While the lid member can be freely opened and closed, it is required that the lid member is not opened carelessly due to impact or vibration. For this reason, a lock mechanism dedicated to the lid member that is allowed to be unlocked only by a user operation is provided.

  In addition, for the control of the image forming apparatus, it is necessary to avoid overlooking the cassette and the lid member in an incomplete state. Once the printing operation is started, the rollers and gears are driven to rotate, and the printing head operates. If the lid member opens and the cassette pops out, not only the printing quality is deteriorated but also the apparatus may be damaged. Therefore, in order to achieve such a problem, a configuration in which detection means is provided for each lock mechanism corresponding to the cassette and the lid member is known. This detects the state of each locking member using a mechanical or optical sensor, and determines whether both the cassette and the lid member are normally locked.

  As described above, the conventional image forming apparatus includes a cassette, a cassette-dedicated locking mechanism, a cassette presence / absence detecting unit, a lid member, a lid-dedicated locking mechanism, and a cassette and a lid member. At least two detection means corresponding to each of the lock mechanisms were provided. However, in such an apparatus that is required to be downsized and reduced in price, reduction of the number of parts and cost reduction are expected, and improvement of the conventional configuration is required. In particular, since the detection means is generally relatively expensive, the effect of improvement by sharing and sharing is also great. So far, a configuration has been proposed in which the detection means for detecting the lock of the cassette or the lid member is also used as the detection means used for other purposes.

  For example, as disclosed in Japanese Patent Application Laid-Open No. H10-228707, there is a device that also uses a detection unit that detects the remaining ink amount to detect the lock state of the ink cartridge. According to the prior art disclosed in this patent document, the blocking unit blocks the optical path of the optical sensor only when the ink cartridge is in the locked state, using the optical sensor as the detection means.

  In addition, as shown in Patent Document 2, for example, in an apparatus including a plurality of lid members, there is one that detects a locked state of two lid members with one detection means. According to the prior art disclosed in this patent document, the mechanical sensor is set to the detection ON state only when both of the two lid members are locked by using a lever member that can freely slide and rotate. To do.

JP 2004-1480 A JP 2005-49446 A

  However, the prior art disclosed in the above-mentioned Patent Document 1 requires a detection means for detecting the remaining amount of ink in the first place, and is effective in a configuration in which the cartridge holder is movable relative to the optical sensor. The use is limited.

  Moreover, in the prior art disclosed in the above-mentioned Patent Document 2, it is essential to add a lever member in exchange for the reduction of the detection sensor, and as a result, reduction in the number of parts cannot be expected.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cassette and lid member locking mechanism that can detect that the cassette and the lid member are both locked while reducing the number of components.

A cassette to be attached to and detached from the device;
A lid member that can be freely opened and closed to cover the cassette;
A locking member that locks and releases the lid member in a first movement direction, and locks and releases the cassette in a second movement direction;
In a cassette locking mechanism comprising a detecting means for detecting the presence or absence of the cassette,
The lock member includes a blocking portion disposed between the cassette and the detection means,
When the lock member is not in a position to normally lock the cassette and the lid member together,
The blocking unit blocks detection by the detection unit.

  According to the present invention, the cassette and the lid member that can be opened and closed so as to cover the cassette are not used, but a locking member in which the roles of the two locking mechanisms are shared by one is used. Use to lock. Furthermore, the detection means dedicated to each of the two previously required is combined with the detection means for detecting the presence or absence of the cassette.

  With this configuration, it is possible to provide a cassette and lid member locking mechanism that can detect that the cassette and the lid member are both locked while reducing the number of components.

It is a perspective view of a lock mechanism part in an embodiment of the present invention. FIG. 3 is a perspective view of the image forming apparatus in a state in which the lock of the lid member is released in the embodiment of the present invention. FIG. 2 is a perspective view of the image forming apparatus in a state where the lock of the ink ribbon cassette is released in the embodiment of the present invention. FIG. 4 is a perspective view showing an enlarged part of the image forming apparatus immediately before locking the ink ribbon cassette in the embodiment of the present invention. FIG. 3 is an enlarged perspective view showing a part of the image forming apparatus immediately before locking the lid member in the embodiment of the present invention. (A) is a schematic diagram which shows the positional relationship of the locking member and the attachment frame in the 1st moving direction in embodiment of this invention. (B) is a schematic diagram showing the positional relationship between the lock member and the mounting frame in the second movement direction in the embodiment of the present invention. (A) is the side view which showed the positional relationship of a locking member and a detection means in the state in which locking was normally completed in embodiment of this invention. (B) is sectional drawing which expands and shows a part of positional relationship of a locking member and a detection means in the state which locked normally in the embodiment of this invention. 1 is a cross-sectional view of an image forming apparatus in an embodiment of the present invention. 1 is a block diagram illustrating a functional configuration of an image forming apparatus in an embodiment of the present invention. (A) is the perspective view of the 1st step in the embodiment of the present invention. (B) is sectional drawing of the 1st step in embodiment of this invention. (C) is sectional drawing which expands and shows a part of 1st step in embodiment of this invention. (A) is the perspective view of the 2nd step in embodiment of this invention. (B) is sectional drawing of the 2nd step in embodiment of this invention. (C) is sectional drawing which expands and shows a part of 2nd step in embodiment of this invention. (A) is the perspective view of the 2nd step in embodiment of this invention. (B) is sectional drawing of the 2nd step in embodiment of this invention. (C) is sectional drawing which expands and shows a part of 2nd step in embodiment of this invention. (A) is the perspective view of the 3rd step in embodiment of this invention. (B) is sectional drawing of the 3rd step in embodiment of this invention. (C) is sectional drawing which expands and shows a part of 3rd step in embodiment of this invention. (A) is a perspective view of the 4th step in the embodiment of the present invention. (B) is sectional drawing of the 4th step in embodiment of this invention. (C) is sectional drawing which expands and shows a part of 4th step in embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the same reference numerals denote the same or corresponding parts throughout the drawings.

  First, the outline of the components described in the claims will be described with reference to the drawings of the preferred embodiments to show the features of the present invention. FIG. 1 is a perspective view of a lock mechanism portion viewed from the inside of the apparatus according to an embodiment of the present invention.

  An ink ribbon cassette 1 is inserted into and removed from the image forming apparatus, and includes an ink ribbon supply roll storage unit 1a and a take-up roll storage unit 1b. In addition, the ink ribbon cassette 1 has a locking surface 1c, and the position of the cassette 1 is regulated on the basis of this surface inside the apparatus. The part reflecting light in the claims is the locking surface 1c, which is formed of, for example, a white material having a glossy surface. Reference numeral 2 denotes a lid member provided with a locking claw 2a, which is an exterior cover that covers the ink ribbon cassette 1 in a closed state. Reference numeral 3 denotes a lock member for locking the ink ribbon cassette 1 and the lid member 2 respectively. The lock member 3 releases the lock of the lid member 2 by sliding in the illustrated X direction as the first movement direction. On the other hand, as will be described later with reference to FIG. 3, the lock member 3 releases the lock of the ink ribbon cassette 1 by rotating in the Y direction as shown in FIG. is there.

  Here, the lock member 3 includes a cassette locking portion 3a and a lid member locking portion 3b, and engages with a locking surface 1c of the ink ribbon and a locking claw 2a of the lid member, respectively. . The lock member 3 has a first operation portion 3c corresponding to a slide operation direction which is a first movement direction, and a second operation portion 3d corresponding to a rotation operation direction which is a second movement direction. Is provided. Although details will be described later, for the purpose of blocking the optical axis in an arbitrary state, a blocking portion 3e is provided so as to be parallel to the locking portion 3a of the cassette. As described in the claims, the blocking portion 3e is formed of, for example, a black material having no gloss on the surface so as not to reflect light. Reference numeral 4 denotes an optical sensor that detects whether the ink ribbon cassette 1 and the lid member 2 are normally locked.

  FIG. 1 is a perspective view when each is normally locked. At this time, the optical sensor 4 is located at a position facing the locking surface 1c of the ink ribbon cassette with a blocking portion 3e provided on the lock member 3 interposed therebetween. Has been placed. The optical sensor 4 includes a light projecting unit and a light receiving unit, and is configured so that the light emitted from the light projecting unit can be detected by the light receiving unit when reflected by the surface of the locking surface 1c of the ink ribbon cassette. . Reference numeral 5 denotes an elastic member that constantly biases the lock member 3 in the lock direction. The elastic member 5 is arranged in an oblique direction with an angle from each direction so as to act on both the X direction which is the first movement direction and the Y direction which is the second movement direction. ing. Therefore, the lock member 3 is configured to return to the initial position in accordance with the urging of the elastic member 5 after the user finishes the operation in the first direction or the second direction.

  2A and 2B are perspective views of the entire image forming apparatus in the embodiment of the present invention. FIG. 2A shows a state in which the lid member 2 is unlocked, and FIG. 2B shows a state in which the ink ribbon cassette 1 is further unlocked. On the other hand, FIG. 2C and FIG. 2D are perspective views showing an enlarged part of the image forming apparatus in the embodiment of the present invention. 2C shows a state immediately before the ink ribbon cassette 1 is locked, and FIG. 2D shows a state immediately before the lid member 2 is further locked.

  Reference numeral 2b denotes a hinge portion that connects the lid member 2 to another cover member and holds the lid member 2 so as to be freely opened and closed. Reference numeral 6 denotes an attachment frame that holds the lock member 3 in a movable manner, and 7 denotes a paper cassette that holds a continuous belt-shaped roll paper P in a wound state. The mounting frame 6 holds not only the lock member 3 but also main components for the image forming apparatus, such as a printing unit and a sheet conveying unit described later. As described above, in this type of apparatus in which miniaturization is desired, the gap relationship between these components including the ink ribbon cassette 1 and the paper cassette 7 must be strictly managed, and high accuracy can be achieved at each mounting position. Required. In this regard, in this embodiment, the mounting frame 6 serves as a common mounting reference for these components, so that the positions of each other can be determined with high accuracy.

  Here, the unlocking operation of the ink ribbon cassette 1 and the lid member 2 will be described with reference to FIGS. 2 (a) and 2 (b). First, in FIG. 2 (a), the lid member 2 is unlocked by sliding the first operation portion 3c of the lock member in the X direction shown in the drawing. Specifically, the lock member 3 moves in the sliding operation direction, the locking member locking portion 3b is disengaged from the locking claw 2a of the lid member, and the lid member 2 is released from the locked state. At this time, if the lid member 2 is opened to the outside of the apparatus with the hinge portion 2b as the rotation center, the state shown in FIG.

  Next, in FIG. 2B, the lock of the ink ribbon cassette 1 is released by rotating the second operation portion 3d of the lock member in the Y direction shown in the drawing. Specifically, the lock member 3 moves in the rotational operation direction, the locking portion 3a of the lock member is separated from the locking surface 1c of the ink ribbon, and the ink ribbon cassette 1 is released from the locked state. At this time, if the ink ribbon cassette 1 is pulled out from the inside of the apparatus, the state shown in FIG. In the state shown in FIG. 2B, for example, it is possible to replace a used ink ribbon cassette with a new one, or to replace with another ink ribbon cassette corresponding to another size. In addition, when the lid member 2 is in the closed state, the second operation portion 3d of the lock member is preferably disposed at a position that is hidden behind the lid member 2 and cannot be operated. This is because if the first operation unit 3c and the second operation unit 3d are exposed from the apparatus, the user may be at a loss as to which operation unit should be operated first. Therefore, the configuration of the present embodiment in which the second operation portion 3d of the lock member is exposed only after the lid member 2 is opened is preferable.

  So far, the unlocking operation of the ink ribbon cassette 1 and the lid member 2 has been described. In contrast to these releasing operations, the ink ribbon cassette 1 and the lid member 2 are locked without the user operating the lock member 3. As shown in FIG. 2C, the ink ribbon cassette 1 is locked immediately before the ink ribbon cassette 1 is completely loaded into the apparatus. The locking portion 3a of the lock member forms a slope portion toward the outside of the apparatus. Immediately before the ink ribbon cassette 1 is completely loaded into the apparatus, the engaging surface 1c reaches the engaging portion 3a of the locking member. Here, the locking surface 1c of the ink ribbon cassette comes into contact with the inclined surface portion of the locking portion 3a of the lock member, and the lock member 3 rotates in the Y direction shown in the figure against the bias of the elastic member 5. When the ink ribbon cassette 1 is further pushed into the apparatus from here, the locking surface 1c of the ink ribbon cassette passes through the locking portion 3a of the lock member, and the lock member 3 returns to its original position in accordance with the bias of the elastic member 5. Return. In this way, the ink ribbon cassette 1 is normally locked.

  The lid member 2 is locked immediately before the closing operation of the lid member 2 is completed, as shown in FIG. The locking claw 2a of the lid member has a key claw shape and forms an inclined surface portion like the locking portion 3a of the lock member. Immediately before the closing operation of the lid member 2 is completely completed, the locking claw 2a reaches the locking portion 3b of the locking member. Here, the slope portion of the locking claw 2a of the lid member comes into contact with the locking portion 3b of the lock member, and the lock member 3 rotates in the X direction shown in the figure against the bias of the elastic member 5. When the lid member 2 is further closed from here, the latching claw 2a of the lid member passes through the latching portion 3b of the lock member, and the lock member 3 engages with the latching claw 2a of the lid member in accordance with the bias of the elastic member 5. Move to the specified position. In this way, the lid member 2 is normally locked.

  FIGS. 3A and 3B are schematic views showing the relationship between the lock member 3 and the attachment frame 6 in the embodiment of the present invention. FIG. 3A shows a state in which the lock member 3 is operated in the first moving direction and the lock of the lid member 2 is released, as in FIG. FIG. 3B shows a state in which the lock member 3 is operated in the second moving direction and the lock of the ink ribbon cassette 1 is released as in FIG. 2B. 3 (a) and 3 (b) correspond to FIGS. 2 (a) and 2 (b), respectively, but particularly the relationship among the lock member 3, the elastic member 5 and the mounting frame 6. The other components are not shown and are not shown in the figure because they are only focused on.

  Reference numerals 3f and 3g denote cylindrical guide portions inserted into holes 6a and 6b provided in the frame member 6, respectively. The shape of the hole 6a provided in the frame member 6 is substantially L-shaped, and the guide portion 3f of the lock member 3 is guided to be substantially L-shaped along the hole 6a. On the other hand, the guide portion 3g of the lock member 3 can move linearly along the hole 6b, and the lock member 3 can rotate around the guide portion 3g. Since the movement direction is restricted by the substantially L-shaped hole 6a and the linearly extending hole 6b, the lock member 3 is rotated in the Y direction in the state shown in FIG. Can not. Conversely, in the state of FIG. 3B in which the lock member 3 is rotated in the Y direction, it cannot slide in the X direction. In other words, in FIG. 3A, while the lock member 3 is slid and the lid member 2 is unlocked, the ink ribbon cassette 1 is not unlocked at the same time. In FIG. 3B, when the lock member 3 is rotated and the lock of the ink ribbon cassette 1 is released, the cover member 2 should already be unlocked, and the two locks are released at the same time. There is no worry. Thus, while operating in a certain moving direction, another moving direction is restricted, so that the problem of the cassette popping out and dropping at the same time as opening the lid member is eliminated.

  3A, the elastic member 5 is stretched in the X direction, and the lock member 3 is biased in the direction opposite to the X direction. In contrast, in the state of FIG. 3B, the elastic member 5 is stretched in the Y direction, and the lock member 3 is urged in the direction opposite to the Y direction. As a result, the elastic member 5 realizes urging in two different directions with one member. That is, in this embodiment, it can be said that the two types of lock mechanisms can be integrated and operated independently, and the number of parts can be reduced and the operability can be improved.

  As described above, in this embodiment, the locking mechanism of the ink ribbon cassette 1 and the locking mechanism of the lid member 2 are shared, and the single locking member 3 plays two roles. However, in the conventional techniques proposed so far, such commonality and integration have not been easy. For example, a configuration that eliminates the cassette-specific locking mechanism and is also used as a lid member locking mechanism is known not only in the field of image forming apparatuses, but there are problems in terms of good operability and high accuracy requirements. It was. First, in the conventional configuration, since the cassette is indirectly pressed by the lid member, the cassette pops out at the same time as the lid member is opened, and handling is complicated such that the cassette is dropped from the apparatus. In addition, since the position of the cassette changes depending on the restriction position of the lid member, the lid member is required to have high accuracy despite being a relatively large part. In this respect, as described so far, the present embodiment does not cause the cassette to pop out at the same time as the lid member is opened, and does not require high accuracy for the lid member. It is an advantage.

  4A and 4B are schematic views showing the positional relationship between the lock member 3 and the detection means 4 in a state where the lock of the ink ribbon cassette 1 and the lock of the lid member 2 are both completed normally. is there. 4A is a side view, and FIG. 4B is an enlarged cross-sectional view of a part thereof. 4 (a) and 4 (b) particularly focus only on the relationship between the lock member 3 and the detection means 4, and other components are omitted and not shown.

  As shown in FIG. 4A, the optical sensor 4 is disposed at a position facing and close to the locking portion 3a of the cassette with the blocking portion 3e interposed therebetween. As shown in FIG. 1, when the ink ribbon cassette 1 is locked, the locking surface 1c of the ink ribbon cassette is regulated by the gap between the locking portion 3a and the blocking portion 3e of the cassette.

  FIG. 4B is a cross-sectional view of the optical sensor 4 side from the clearance between the locking portion 3a and the blocking portion 3e of the lock member, that is, the locking surface 1c of the ink ribbon cassette. The blocking part 3e is provided with a through hole 3h. The through-hole 3h is just in line with the optical sensor 4 when the lid member 2 is locked. As described in the claims, the ink ribbon cassette 1 reflects the light emitted from the optical sensor 3, whereas the blocking portion 3e is formed of a non-reflective material. Therefore, when the blocking unit 3e overlaps and covers the optical sensor 4, the optical sensor 4 is blocked from light projection and light reception, and enters the detection OFF state. On the other hand, as shown in FIG. 4B, if the through hole 3h is in a position aligned with the optical sensor 4, the light emitted from the optical sensor 4 passes through the blocking portion 3e, and the cassette is locked. It reaches the surface of the part 3a. Here, if the ink ribbon cassette 1 is in a locked state and the locking surface 1c of the ink ribbon cassette is regulated by the gap between the locking portion 3a and the blocking portion 3e of the cassette, the light emission of the optical sensor 4 is blocked. It should penetrate the part 3e and reach the surface of the locking surface 1c of the ink ribbon cassette. Such a relationship is an important feature in the present invention and is indispensable for detecting whether or not both the ink ribbon cassette 1 and the lid member 2 are normally locked, and will be described in detail later.

  Although the above description has focused on the component parts recited in the claims, the component parts and the role of the image forming apparatus to which the present invention is particularly applied will be described here. FIG. 5 is a cross-sectional view of the image forming apparatus in the embodiment of the present invention.

  Reference numeral 8 denotes a thermal head as printing means. Reference numeral 9 denotes a platen roller disposed so as to face the thermal head 8 with the sheet conveyance path interposed therebetween. The illustrated image forming apparatus records an image by driving a heating element of a thermal head 8 serving as a recording unit based on image information and melt-transferring the ink impregnated in the ink ribbon 1d onto the roll paper P. It is going. The ink ribbon 1d covers the printing area of the roll paper P and is slightly larger than the size of the ink ribbon 1d. The yellow (Y), magenta (M), and cyan (C) ink layers and the overcoat (OC) layer are displayed on the screen. It is common that they are arranged side by side. P is a roll paper held in a state of being wound around a roller-shaped bobbin 7a. A plurality of types of sizes such as a card size, an L size, and a post card size are prepared for the roll paper P, and each is stored in a dedicated or combined paper cassette 7. When the printing operation is performed, preparation is performed by inserting the ink ribbon cassette 1 and the paper cassette 7 corresponding to an arbitrary size into the apparatus main body. Reference numeral 10 denotes a paper feed roller, 11 denotes a capstan roller, and 12 denotes a pinch roller. These are paper conveying means.

  As shown in FIG. 5, in a transport state in which the roll paper P can be transported and the paper can be fed and stored, the paper feed roller 10 is in a position in pressure contact with the roll paper P held in the paper cassette 7. It is in. Here, if the paper feed roller 10 is rotationally driven as a paper feed operation, the leading edge of the roll paper P reaches the capstan roller 11. The capstan roller 11 is a metal active roller that mainly transports paper after a paper feeding operation. The pinch roller 12 as a driven roller is elastically biased in the normal direction of the shaft portion of the capstan roller 11 by a spring member (not shown). Reference numeral 13 denotes a cutter unit which is a sheet cutting means. Reference numeral 13a denotes a cutter movable blade, and reference numeral 13b denotes a cutter fixed blade which is disposed so as to face the cutter movable blade 13a across the conveyance path of the roll paper P. In order to cut the roll paper P into an arbitrary length, the image forming apparatus using the roll paper P requires, for example, a metal cutter movable blade 13a and a cutter fixed blade 13b that are partially sharpened. The roll paper P is cut by reciprocating the cutter movable blade 13a in a direction perpendicular to the surface of the paper, and rubbing the cutter movable blade 13a and the cutter fixed blade 13b with scissors between the upper and lower blades. In this embodiment, a scissor-like cutter unit 13 that moves in a direction perpendicular to the surface of the paper is shown as the paper cutting means. Other known paper cutting means include a rotary cutter that reciprocates in the width direction (lateral direction) of the paper, and the present invention does not limit the type of paper cutting means.

  FIG. 6 is a block diagram showing a functional configuration of the image forming apparatus in the embodiment of the present invention.

  A main controller 14 controls the entire image forming apparatus. 4 is an optical sensor which is a feature of this embodiment, and 15 is a paper cassette detection sensor. As described above, the optical sensor 4 detects the presence or absence of the ink ribbon cassette 1 and the two locked states. On the other hand, the paper cassette detection sensor 15 detects the presence or absence of the paper cassette 7. In order to prevent malfunction, in this embodiment, the image forming apparatus shifts to the print start operation only when both the optical sensor 4 and the paper cassette detection sensor 15 are in the ON state. Reference numeral 16 denotes a paper detection sensor, which is disposed at a substantially intermediate position between the platen roller 9 and the capstan roller 11 on the paper conveyance path, and the leading end of the roll paper P drawn from the paper cassette 7 is captured when the paper is conveyed. It is detected that the vehicle has passed behind the stun roller 11. Reference numeral 17 denotes an ink ribbon detection sensor that detects an identification band applied to the leading end portion of each color of the ink ribbon. Reference numeral 18 denotes a cutter detection sensor which detects whether the cutter movable blade 13a is in the standby position or the cutting position. Reference numeral 19 denotes a paper feed motor driver for driving the paper feed motor 20. The paper feed motor 20 is connected to the paper feed roller 10, the capstan roller 11 and the like through a rotation mechanism. An ink ribbon winding motor driver 21 controls the rotation of the ink ribbon winding motor 22. In a state where the ink ribbon cassette 1 is mounted, the take-up roll storage unit 1b and the ink ribbon winding motor 22 are connected via a rotation mechanism, and the ink ribbon winding motor driver 21 winds and winds the ink ribbon 1d. Be controlled.

  The winding operation of the ink ribbon 1d by the ink ribbon winding motor 22 is controlled based on the detection result of the ink ribbon detection sensor 17. Reference numeral 23 denotes a head up / down motor driver. The driver 23 controls the rotation of the head up / down motor 24 that moves the thermal head 8 up and down to operate the thermal head 8 between the printing position and the retracted position. Reference numeral 25 denotes a cutter motor driver. The cutter motor driver 25 controls the cutter motor 26 that drives the cutter movable blade 13a to cut the roll paper P. A display control unit 27 controls the display unit 28 including a display screen such as an LCD. The display unit 28 displays image data to be printed or displays a menu for inputting setting data necessary for printing. An operation unit 29 includes a power switch for instructing ON / OFF of the power of the image forming apparatus, a selection switch for selecting various menus displayed on the display unit 28, and the like.

  7 to 11 show a schematic configuration of the lock mechanism in the embodiment of the present invention, and the lock member 3 and the optical sensor when the ink cassette 1 and the lid member 2 are sequentially locked in stages. 4 is a diagram illustrating the positional relationship with FIG. 4 in detail in each case.

  FIG. 7A is a perspective view showing the positional relationship of the lock member 3 in the first stage when the ink ribbon cassette 1 is not loaded in the apparatus and the lid member 2 is in the open state. FIG. 7B is a cross-sectional view of the locking member 3a facing the optical sensor 4 from the locking portion 3a, and FIG. 7C is a cross-sectional view of the optical sensor 4 in which a part thereof is further enlarged. FIG.

  The perspective view and the cross-sectional view shown in FIG. 7 assume that the user has opened the lid member 2 so as to load the ink ribbon cassette 1 into the apparatus. At this time, the guide 3f of the lock member is in contact with the bending point in the hole 6a of the frame member, and the guide 3g of the lock member is in contact with the left end of the hole 6b of the frame member. Thus, when the ink ribbon cassette 1 is not loaded in the apparatus and the lid member 2 is in the open state, the lock member 3 is always biased to this state by the elastic member 5. Here, focusing on the positional relationship between the blocking member 3e of the lock member and the optical sensor 4, the blocking member 3e of the lock member is covered on the optical sensor 4. As described in the claims, the blocking portion 3e of the lock member is formed of, for example, a black material having no gloss on the surface so as not to reflect the light emitted from the light projecting portion of the optical sensor 4. That is, when the ink ribbon cassette 1 is not loaded in the apparatus and the lid member 2 is in the open state, the optical sensor 4 is always in the detection OFF state.

  FIG. 8A is a perspective view showing the positional relationship between the lock member 3 and the lid member 2 in the second stage when the ink ribbon cassette 1 is loaded in the apparatus but the lock is not normally completed. 8B is a cross-sectional view of the locking member 3a facing the optical sensor 4 side from the locking portion 3a, and FIG. 8C is a cross-sectional view at the position of the optical sensor 4 further showing a part thereof enlarged. FIG.

  The perspective view and cross-sectional view shown in FIG. 8 assume a state in which the user attempts to close the lid member 2 although the locking of the ink ribbon cassette 1 has not been normally completed. At this time, the guide 3f of the lock member is positioned near the upper end of the hole 6a of the frame member, and the guide 3g of the lock member is in contact with the left end of the hole 6b of the frame member. When the lock of the ink ribbon cassette 1 is not normally completed, the lock member 3 cannot move in the slide operation direction. Therefore, even if the lid member 2 is closed, as shown in FIG. 9 (b), the latching claw 2a of the lid member and the latching portion 3b of the lock member come into contact with each other and stop in the state shown in FIG. 9 (a). End up. When attention is paid to the positional relationship between the blocking member 3e of the lock member and the optical sensor 4, the blocking member 3e of the lock member is covered on the optical sensor 4 as in the case of FIG. That is, when the lock of the ink ribbon cassette 1 is not normally completed, the optical sensor 4 is always in the detection OFF state.

  Unlike FIG. 8, FIG. 9A is a perspective view showing the positional relationship between the lock member 3 and the ink ribbon cassette 1 in the second stage when the ink ribbon cassette 1 is loaded into the apparatus and the lock is normally completed. FIG. FIG. 9B is a cross-sectional view of the locking member 3a facing the optical sensor 4 from the locking portion 3a, and FIG. 9C is a cross-sectional view at a position of the optical sensor 4 that is further enlarged. FIG.

  The perspective view and the cross-sectional view shown in FIG. 9 assume a state in which the user has normally completed the loading of the ink ribbon cassette 1 and has attempted to close the lid member 2. At this time, as in the case of FIG. 7, the guide 3f of the lock member is in contact with the bending point in the hole 6a of the frame member, and the guide 3g of the lock member is in contact with the left end of the hole 6b of the frame member. Thus, when the ink ribbon cassette 1 is normally loaded in the apparatus and the lid member 2 is in the open state, the lock member 3 is always biased to this state by the elastic member 5. When attention is paid to the positional relationship between the blocking member 3e of the locking member and the optical sensor 4, the blocking member 3e of the locking member is covered on the optical sensor 4 as in the case of FIGS. ing. That is, when the ink ribbon cassette 1 is normally locked and the lid member 2 is not yet locked, the optical sensor 4 is always in the detection OFF state.

  FIG. 10A is a perspective view showing the positional relationship between the lock member 3 and the lid member 2 in the third stage where the lock of the lid member 2 is not normally completed while the ink ribbon cassette 1 is normally locked. It is. 10B is a cross-sectional view of the locking member 3a facing the optical sensor 4 side from the locking portion 3a, and FIG. 10C is a cross-sectional view at a position of the optical sensor 4 showing an enlarged part thereof. FIG.

  10, the lock member guide 3f is located near the right end of the frame member hole 6a, and the lock member guide 3g is located near the right end of the frame member hole 6b. . When the locking of the lid member 2 is not normally completed, the lock member 3 cannot move in the rotation operation direction. Therefore, the lock of the ink ribbon cassette 1 that has been completed once is not inadvertently released. Here, paying attention to the positional relationship between the blocking member 3e of the lock member and the optical sensor 4, the blocking member 3e of the locking member covers the optical sensor 4 as in the case of FIGS. It is in a state. That is, when the locking of the lid member 2 is not normally completed, the optical sensor 4 is always in the detection OFF state.

  FIG. 11A is a perspective view showing the positional relationship between the lock member 3 and the lid member 2 in the fourth stage in which both the ink ribbon cassette 1 and the lid member 2 are normally locked. 11B is a cross-sectional view of the locking member 3a facing the optical sensor 4 side from the locking portion 3a, and FIG. 11C is a cross-sectional view of the optical sensor 4 in which a part thereof is further enlarged. FIG.

  The perspective view and the cross-sectional view shown in FIG. 11 assume a state in which the user's operation is completed and the printing operation is started. At this time, the guide 3f of the lock member is positioned approximately in the middle of the bending point and the right end of the hole 6a of the frame member, and the guide 3g of the lock member is positioned approximately in the middle of the hole 6b of the frame member. When both the ink ribbon cassette 1 and the lid member 2 are normally locked, as shown in FIG. 11 (b), the state in which the latching claw 2a of the lid member and the latching portion 3b of the lock member are firmly fitted together. Become. Here, when attention is paid to the positional relationship between the blocking portion 3e of the lock member and the optical sensor 4, the through hole 3h of the lock member just overlaps the optical sensor 4, and the optical sensor 4 and the through hole 3h are in a straight line. They are lined up. At this time, the light emitted from the light projecting portion of the optical sensor 4 passes through the through hole 3h of the lock member and reaches the surface of the locking surface 1c of the ink ribbon cassette. As described in the claims, the locking surface 1c of the ink ribbon cassette is formed of, for example, a white material having a glossy surface so as to reflect the light of the light projecting portion. Therefore, the light receiving part of the optical sensor 4 can detect the light reflected by the surface of the locking surface 1c. That is, when both the ink ribbon cassette 1 and the lid member 2 are normally locked, the optical sensor 4 is only in the detection ON state unlike the other cases shown in FIGS. In this embodiment, it is determined that printing can be started from this detection ON state, and the process proceeds to the subsequent printing operation.

  The first preferred embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various modifications and changes can be made within the scope of the gist.

1 ... Ink ribbon cassette 2 ... Lid member 3 ... Lock member 3e ... Blocking part 3h ... Through hole 4 ... Optical sensor 5 ... Elastic member 6 ... Mounting frame 7 ... Paper cassette 8 ... Thermal Head 9 Platen roller 10 Feed roller 11 Capstan roller 12 Pinch roller 13 Cutter unit
P ... Roll paper

Claims (7)

A cassette to be attached to and detached from the device;
A lid member that can be opened and closed so as to cover the cassette, a lock member that locks and releases the lid member in the first movement direction, and a lock member that locks and releases the cassette in the second movement direction, and whether or not the cassette is present. A cassette locking mechanism comprising a detecting means for detecting,
The lock member includes a blocking portion disposed between the cassette and the detection means, and when the lock member is not in a position to normally lock the cassette and the lid member, the blocking portion detects the detection. A cassette locking mechanism characterized in that detection by means is cut off. The detecting means is an optical sensor including a light projecting unit and a light receiving unit, and at least a part of the cassette reflects the light from the light projecting unit, whereas the blocking unit of the lock member is the light projecting unit. The cassette locking mechanism according to claim 1, wherein the light is not reflected. The blocking portion of the lock member includes a through hole, and the detection means and the through hole are aligned in a straight line when the lock member is in a position where the cassette and the lid member are normally locked together. The cassette locking mechanism according to claim 1 or 2. The lock member includes a first operation unit corresponding to the first movement direction and a second operation unit corresponding to the second movement direction, and the second operation unit includes the lid member. The cassette locking mechanism according to any one of claims 1 to 3, wherein the cassette locking mechanism is exposed only in an open state. The first movement direction and the second movement direction are a slide operation direction on a straight line or a rotation operation direction having a rotation center, respectively. A cassette locking mechanism according to claim 1. 6. The cassette locking mechanism according to claim 1, wherein the first movement direction and the second movement direction intersect each other. The image according to any one of claims 1 to 6, wherein the cassette contains ink or paper, and the printing operation is executed only when the detection unit detects the cassette. Forming equipment.