JP4248426B2 - Paper cassette - Google Patents

Description

  The present invention relates to a paper feed cassette used for stocking a large number of sheets to be supplied to an apparatus in advance.

  The paper feed cassette is used for feeding cut paper or the like in an image forming apparatus represented by a copying machine or a printer. Many paper feeders in an image forming apparatus stock a large number of papers before printing in a paper feed cassette and separate and feed the papers one by one from the uppermost layer of papers stacked in the cassette.

  On the other hand, with the recent promotion of downsizing of the image forming apparatus, the floor area of the image forming apparatus has been reduced, and the paper feed cassette has to be reduced. As a result, the paper size that can be stocked in advance is limited to a small paper size. Although there is no particular problem in normal use, there are problems that printing cannot be performed when a large number of large-size sheets are to be printed, or a large-size paper feed cassette needs to be prepared.

In view of this, a paper feed cassette having a size suitable for the image forming apparatus is usually proposed, but a paper feed cassette that can be increased in size as required has been proposed. Examples of such paper feed cassettes can be found in Patent Documents 1 to 3.
Japanese Utility Model Publication No. 7-12346 (2nd page, FIG. 1) JP-A-9-110191 (page 3-4, FIG. 1) Japanese Patent Laid-Open No. 11-29211 (page 3, FIG. 2)

  Each of the paper feed cassettes described in Patent Documents 1 to 3 includes a main frame and a slide frame that engages with the main frame and is movable in the paper supply direction. By moving the slide frame, the paper feed cassette can be enlarged in the paper supply direction.

  The paper feed cassette described in Patent Document 1 positions a slide frame by engaging an elastic locking claw formed in one frame and a locking hole formed in the other frame. is there. However, this paper feed cassette is not provided with a lock mechanism for locking the position of the slide frame. Therefore, it may happen that the slide frame is moved carelessly.

  The paper feed cassette described in Patent Document 2 is provided with a locking boss formed on one frame and an engagement with a lock lever provided on the other frame and having a locking portion at the tip. Positioning and locking are performed. However, with this lock mechanism, the larger the slide frame is, the longer the lock lever needs to be. If the lock lever is made by resin molding, there is a question about its strength, and the lock cannot be held firmly. there is a possibility.

  The paper feed cassette described in Patent Document 3 is a pin-shaped member having two claws formed on one frame, and a pin provided on the other frame and movable between a lock position and an unlock position. The slide frame is positioned and locked by engagement with the shaped member. However, this lock mechanism has poor operability because the slide frame cannot be locked unless the user intentionally moves the pin-shaped member to the lock position. If the lock is forgotten, the slide frame moves unintentionally, and the paper shifts from the paper feed position, causing a paper feed failure. In addition, since the base provided with the pin-like member protrudes greatly from the inner surface of the frame in the direction in which the paper exists, the size of paper that can be stacked in the paper feed cassette is reduced. In order to avoid this, it is difficult to arrange this lock mechanism at the bottom of the inner surface of the frame from the configuration of the hook-shaped member and the pin-shaped member.

  The present invention has been made in view of the above points, and provides a paper feed cassette that stocks a large number of papers and can be smoothly expanded and contracted according to the paper size and can be easily locked. For the purpose.

  In order to solve the above problems, the present invention provides a main body, a slide member that engages with the main body and is movable according to the paper size, and is provided between the main body and the slide member. A locking mechanism that locks the plurality of locking grooves shifted in the moving direction of the slide member, and moves in a direction perpendicular to the moving direction of the slide member and engages with the locking groove. Engaging the locking piece, the urging means for urging the locking piece to the locking position, and the engagement for engaging the locking piece displaced against the urging means and constraining the locking piece to the unlocking position And a slope that is provided between the plurality of lock grooves, contacts the lock piece when the slide member is moved, and releases the lock piece from the engagement portion.

  The main body is a main frame that supports the downstream side in the paper supply direction, and the slide member engages with the main frame to support the upstream side in the paper supply direction, and supplies paper according to the paper size. The slide frame is movable in the direction, and the lock mechanism is provided at a portion where the main frame and the slide frame overlap.

  Further, the portion where the lock piece and the engagement portion engage with each other is formed by a slope that generates a component force for maintaining the unlocked state by the biasing means between the lock piece and the engagement portion. It was decided.

  Further, the biasing means biases the lock piece in a direction that strengthens the maintenance of the unlocked state of the lock piece while changing the angle from the moving direction of the lock piece.

  Further, the biasing means is constituted by a compression coil spring, and generates the component force for maintaining the unlocked state by setting the angle and / or position of the seat that receives the end.

  In addition, a protrusion that changes the axial direction of the compression coil spring to an angle different from the moving direction of the lock piece is provided on the seat of the lock piece that receives the end of the compression coil spring.

  Moreover, the said seat which receives the edge part of the said compression coil spring of the said body was comprised by the slope which changes the axial direction of a compression coil spring into the angle different from the moving direction of the said lock piece.

  According to the configuration of the present invention, the lock mechanism that locks the movement of the slide member includes a plurality of lock grooves, a lock piece that engages with the lock groove, and an urging unit that urges the lock piece to the lock position. An engagement portion that restrains the lock piece displaced against the biasing means at the unlocking position, and is provided between the plurality of lock grooves, and contacts the lock piece when moving the slide member, Since it is composed of a slope that releases the lock piece from the engaging part, it can be restrained to the unlocked position simply by moving the lock piece by hand, and it can be restrained to the unlocked position simply by moving the slide member. The released lock piece can be released, and the slide member can be automatically locked when the lock piece reaches the lock groove position. Therefore, since the slide member is not required to be locked, the operability is very good and convenient. In addition, the slide member cannot be moved unintentionally forgetting to lock.

  The main body is a main frame that supports the downstream side in the paper supply direction, and the slide member engages with the main frame to support the upstream side in the paper supply direction, and supplies paper according to the paper size. Since the slide frame is movable in the direction, larger sheets can be stacked in the sheet feeding direction in the sheet feeding cassette. Therefore, it is possible to expand the application of the paper feed cassette. In addition, since the lock mechanism is provided at a portion where the main frame and the slide frame overlap, for example, by providing the lock mechanism at the bottom of the inner surface of the frame, it does not interfere with the stacking of sheets, and It is possible to stack large size sheets along the inner wall.

  Further, the portion where the lock piece and the engaging portion engage with each other is configured by a slope that generates a component force for maintaining the unlocked state by the biasing means between the lock piece and the engaging portion. Therefore, this slope action prevents the lock piece from easily moving from the unlock position. Accordingly, it is possible to prevent the slide member from being unintentionally locked due to vibration or the like when operating the paper feed cassette, and the operability of the paper feed cassette is improved.

  Further, since the biasing means biases the lock piece in a direction that strengthens the unlocked state maintenance of the lock piece and changes the angle from the moving direction of the lock piece, the lock piece tends to stay at the unlocked position. Can be. Accordingly, it is possible to prevent the slide member from being unintentionally locked due to vibration or the like when operating the paper feed cassette, and to improve the operability of the paper feed cassette.

  Further, the biasing means is constituted by a compression coil spring, and generates a component force for maintaining the unlocked state by setting the angle and / or position of the seat that receives the end thereof. By devising the design, it is possible to easily change the urging direction of the lock piece and strengthen the lock release state of the lock piece.

  In addition, since the seat of the lock piece that receives the end of the compression coil spring is provided with a protrusion that changes the axial direction of the compression coil spring to an angle different from the moving direction of the lock piece, the protrusion is locked. The component force for maintaining the unlocked state can be easily generated in the compression coil spring simply by providing it at the connecting portion with the one compression coil spring.

  Also, since the seat of the main body that receives the end of the compression coil spring is configured with a slope that changes the axial direction of the compression coil spring to an angle different from the moving direction of the lock piece, the slope is compressed by the main body. A component force for maintaining the unlocked state can be easily generated in the compression coil spring simply by being provided at the connecting portion with the coil spring.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  First, the outline of the structure of the paper feed cassette according to the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of a sheet feeding cassette according to an embodiment of the present invention, and shows a reduced state, and FIG. 2 shows an expanded state.

  The paper feed cassette 1 is accommodated in a lower portion of an image forming apparatus such as a copying machine (not shown), and a horizontal protrusion 2 provided on a side surface is engaged with a rail inside the image forming apparatus, and an arrow shown in the figure. It is slid horizontally in the direction of A and inserted. A panel 3 is provided on the front surface of the paper feed cassette 1, and this panel 3 plays a role of constituting a part of a housing at the lower front of the image forming apparatus. The paper feed cassette 1 is composed of a flat box having an open top surface, and stacks and stores paper sheets from the top surface direction. Above the front part of the paper feed cassette 1, paper feed means (not shown) is provided, and the paper is supplied in the direction of arrow B shown in the figure.

  Main elements constituting the paper feed cassette 1 are a main frame 10 which is a main body and a slide frame 20 which is a slide member. The sheets are stacked on tray units 11 and 21 provided on the inner surfaces of these frames. The main frame 10 supports the downstream side in the paper supply direction. The slide frame 20 is engaged with the main frame 10, supports the upstream side in the paper supply direction, and is movable in the paper supply direction according to the paper size. FIG. 2 shows the expanded state of the paper feed cassette 1, but the slide frame 20 is pulled out of the main frame 10 beyond the position shown in FIG. There is no. A lock mechanism 30 that locks the movement of the slide frame 20 is provided at a portion where the main frame 10 and the slide frame 20 overlap. Two lock mechanisms 30 are provided, one on each of the left and right sides from the center in the direction perpendicular to the paper supply direction.

  Next, a detailed configuration of the lock mechanism 30 of the paper feed cassette 1 according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a partially enlarged perspective view of the paper feed cassette showing an expanded state, and FIG. 4 is a vertical partial cross-sectional view of the lock groove and slope shown in FIG. 5 is a top perspective view of the lock piece shown in FIG. 3, and FIG. 6 is a bottom perspective view of the same. 7 is a partially enlarged perspective view of the same sheet feeding cassette as in FIG. 3, showing a reduced state, FIG. 8 is a horizontal sectional perspective view showing the lock portion of FIG. 7, and showing the locked state, FIG. Fig. 8 is a vertical sectional view showing the lock portion of Fig. 8, as viewed from the downstream side in the paper supply direction.

  The lock mechanism 30 includes a lock groove 31, a lock piece 32, a spring 33, a lock piece engaging portion 34, and a slope 35.

  As shown in FIG. 3, the lock groove 31 is provided on the bottom surface 22 of the tray portion 21 of the slide frame 20. Three lock grooves 31 are provided with their positions shifted in the moving direction of the slide frame 20 which is the paper supply direction. A first lock groove 31a is provided on the most upstream side in the sheet supply direction, a second lock groove 31b is then shifted to the downstream side, and a third lock groove (not shown) is further shifted to the downstream side. FIG. 3 shows a state in which the lock piece 32 is engaged with the third lock groove. On the bottom surface 22, there is a lock piece sliding surface 23 that extends downward in the moving direction of the slide frame 20, which is recessed slightly outward from the center of the direction perpendicular to the moving direction of the slide frame 20 (hereinafter referred to as the paper width direction). Further, a step 24 is provided adjacent to the lock piece sliding surface 23 and further disposed near the center of the slide frame 20. The lock groove 31 is provided in the vertical wall 24a (see FIG. 4) of the step 24 so as to be concave from the outside to the inside of the slide frame 20.

  As shown in FIGS. 8 and 9, the lock piece 32 is stored in the lock piece storage portion 13 provided on the bottom surface 12 of the tray portion 11 of the main frame 10. The lock piece 32 moves in the paper width direction in the lock piece storage portion 13 and engages with the lock groove 31. 5 and 6, the lock piece 32 is provided with an operation portion 32a that is operated by a finger when the lock piece 32 is moved. The user can touch the operation portion 32a by inserting a finger from the opening 14 (see FIGS. 3 and 7) provided above the lock piece storage portion 13. One side surface of the operation portion 32a functions as an engagement portion contact surface 32b that contacts and engages with the lock piece engagement portion 34. One end of the locking piece 32 is provided with a pin 32 c that is a seat for receiving the end of the spring 33. The pin 32 c is provided in parallel with the moving direction of the lock piece 32. A support protrusion 32 d that comes into contact with the lock piece sliding surface 23 of the slide frame 20 is provided below the lock piece 32. On the upper surface of the lock piece 32, an arrow 32e pointing in a direction from the lock position to the lock release position is integrally formed.

  As shown in FIGS. 8 and 9, the spring 33 is provided between the main frame 10 and the lock piece 32 in the lock piece storage portion 13. The spring 33 is a biasing means that biases the lock piece 32 to the lock position. One end of the spring 33 is inserted into a pin 15 that is a seat provided on the main frame 10, and the other end is inserted into a pin 32 c provided on the lock piece 32. As a result, the spring 33 biases the lock piece 32 in the direction from the outer side to the inner side in the paper width direction, that is, the direction toward the lock position. In addition, although the spring 33 is comprised with a compression coil spring, it is also possible to use rubber | gum, a leaf | plate spring, etc. as an urging means.

  As shown in FIGS. 8 and 9, the lock piece engaging portion 34 is provided in the vicinity of the portion of the lock piece storage portion 13 where the operation portion 32 a of the lock piece 32 exists. The lock piece engaging portion 34 is a protrusion that protrudes from the inner wall of the lock piece storage portion 13 toward the lock piece 32. In the locked state shown in FIGS. 8 and 9, the lock piece engaging portion 34 is located below the operation portion 32 a of the lock piece 32. Then, when the lock piece 32 moves in the unlocking direction against the spring 33, the lock piece engaging portion 34 comes into contact with and engages with the engagement portion abutting surface 32 b of the lock piece 32. Is constrained to the unlocked position (see FIGS. 10 and 11).

  As shown in FIGS. 3 and 4, the slope 35 is configured as a part of a lock piece sliding surface 23 provided on the bottom surface 22 of the tray portion 21 of the slide frame 20. The lock piece sliding surface 23 extends in the moving direction of the slide frame 20 as described above, and includes the lowest surface 23a where the lock groove 31 is present, the highest surface 23b present at the center portion between the lock grooves, It is comprised with the slope 35 which exists in between. As the slide frame 20 moves, the lock piece 32 moves on the lock piece sliding surface 23 while sliding the support protrusion 32d. In the process of moving the lock piece 32, the slope 35 pushes the lock piece 32 upward to release the lock piece 32 restrained at the lock release position from the lock piece engaging portion 34.

  Subsequently, the operation of the lock mechanism 30 is expanded from the state in which the paper feed cassette 1 is in the contracted state and locked at the position of the first lock groove 31a, and is locked at the position of the second lock groove 31b. The process of changing to the state to be performed will be described with reference to FIGS. 10 to 15 in addition to FIGS.

  10 is a horizontal cross-sectional perspective view showing the lock portion of FIG. 7, showing the unlocked state, FIG. 11 is a partially enlarged perspective view showing the lock piece engaging portion of FIG. 10, and FIG. 12 is the lock portion of FIG. FIG. 2 is a vertical sectional view showing the sheet as viewed from the downstream side in the paper supply direction. 13 is a partially enlarged perspective view of the same paper cassette as in FIG. 7 and shows a state in the middle of expansion. FIG. 14 is a vertical sectional view of the lock portion in FIG. 13 and is viewed from the downstream side in the paper supply direction. It is a thing. FIG. 15 is a partially enlarged perspective view of the paper feed cassette locked at the second lock groove position.

  When the paper feed cassette 1 is in the contracted state shown in FIG. 7, the slide frame 20 is locked at the position of the first lock groove 31a (see FIG. 3). As shown in FIGS. 8 and 9, the lock piece 32 engages with the first lock groove 31a, and the slide frame 20 cannot move to the expanded state.

  Next, the finger is put on the operation portion 32 a of the lock piece 32, and the lock piece 32 is moved against the spring 33 in accordance with the arrow 32 e formed on the lock piece 32 outward in the paper width direction. When the movement progresses and the operation portion 32a is removed from the overlap with the lock piece engaging portion 34, the lock piece 32 sinks downward by the force of the finger. Here, as shown in FIGS. 10 to 12, the engagement portion abutting surface 32 b of the lock piece 32 abuts on the end surface of the lock piece engagement portion 34, and the lock piece 32 is restrained. The lock piece 32 remains in this unlocked position by the action of the spring 33 that urges the lock piece 32 to the lock position and the friction between the contact surfaces of the engagement portion contact surface 32b and the lock piece engagement portion 34. It will never move to the locked position.

  Since the slide frame 20 is unlocked as described above, the slide frame 20 can be moved toward the expanded state. When the slide frame 20 is moved, the support protrusion 32d (see FIG. 12) provided below the lock piece 32 comes into contact with the slope 35 (see FIG. 13). When the slide frame 20 further moves, the lock piece 32 is pushed upward by the slope action of the slope 35. When the slide frame 20 continues to move and the lock piece 32 is pushed up, as shown in FIG. 14, the operating portion 32a is positioned above the lock piece engaging portion 34, and the lock piece 32 is engaged with the lock piece. The joint 34 is released. As a result, the lock piece 32 should be moved to the lock position by the action of the spring 33, but the slide piece 20 is not locked because it abuts against the step 24 next to the lock piece sliding surface 23.

  As shown in FIG. 15, when the lock piece 32 reaches the position of the second lock groove 31 b, the lock piece 32 is automatically moved to the lock position by the action of the spring 33. Therefore, the lock piece 32 and the second lock groove 31b are engaged, and the slide frame 20 is locked again (see FIG. 9).

  Thus, the lock mechanism 30 that locks the movement of the slide member includes a plurality of lock grooves 31, a lock piece 32 that engages with the lock groove, and an urging unit that urges the lock piece 32 to the lock position. A spring 33, a lock piece engaging portion 34 for restraining the lock piece 32 displaced against the spring 33 at the unlocking position, and the plurality of lock grooves, and when moving the slide member Since it comprises a slope 35 that contacts the lock piece 32 and releases the lock piece 32 from the lock piece engaging portion 34, the lock piece 32 can be restrained to the unlocking position by simply moving the lock piece 32 by hand, and the slide member The lock piece 32 constrained to the unlocking position can be released simply by moving, and the slide member can be automatically locked when the lock piece 32 reaches the lock groove position. A. Therefore, since the slide member is not required to be locked, the operability is very good and convenient. In addition, the slide member cannot be moved unintentionally forgetting to lock.

  The main body is a main frame 10 that supports the downstream side in the paper supply direction, and the slide member supports the upstream side in the paper supply direction and engages with the main frame 10 to change the paper according to the paper size. Since the slide frame 20 is movable in the supply direction, larger sheets can be stacked in the paper supply cassette 1 in the paper supply direction. Therefore, it is possible to expand the usage of the paper feed cassette 1. In addition, since the lock mechanism 30 is provided in a portion where the main frame 10 and the slide frame 20 overlap each other, for example, by providing the lock mechanism 30 at the bottom of the inner surface of the frame, there is no hindrance to stacking sheets. It is possible to stack large size sheets along the inner wall of the sheet feeding cassette 1.

  Next, a detailed configuration of the lock mechanism 30 of the paper feed cassette 1 according to the second embodiment of the present invention will be described with reference to FIGS. 16 is a top perspective view of the lock piece, and FIG. 17 is a side view of the same. FIG. 18 is a vertical sectional view showing the lock portion in the unlocked state of the paper feed cassette, viewed from the downstream side in the paper supply direction. Since the basic configuration of this embodiment is the same as that of the first embodiment described with reference to FIGS. 3 to 15, the components common to the first embodiment are described in the drawings. And the description thereof will be omitted.

  16 and 17, the lock piece 32 is provided with an operation portion 32a that is operated with a finger when the lock piece 32 is moved. On one side surface of the operation portion 32a, an engagement portion abutting surface 32b that abuts and engages with a lock piece engagement portion 34 provided on the lock piece storage portion 13 of the bottom surface 12 of the main frame 10 is provided. . The engaging part contact surface 32b is not perpendicular to the moving direction of the lock piece 32 (arrow C in FIG. 17), but is formed as an inclined surface.

  As shown in FIG. 18, the lock piece engaging portion 34 is provided in the vicinity of the portion of the lock piece storage portion 13 where the operation portion 32 a of the lock piece 32 exists. In the lock piece engaging portion 34, a lock piece contact surface 34 a is provided on a surface with which the engagement portion contact surface 32 b of the lock piece 32 is engaged. The lock piece abutting surface 34a is configured by a slope inclined at substantially the same angle in the same direction as the inclination of the engaging portion abutting surface 32b of the lock piece 32.

  In the unlocked state shown in FIG. 18, the lock piece 32 is biased in the locking direction, that is, leftward by the spring 33, and the lock piece 32 is actuated by the slope action of the portion where the lock piece 32 and the lock piece engaging portion 34 contact each other. A force acts to move 32 downward. In order to displace the lock piece 32 to the lock position, the lock piece 32 must be moved upward to release the engagement with the lock piece engaging portion 34. Therefore, a downward force acting on the lock piece 32 is required. Thus, the unlocked state is maintained. In this manner, the lock piece 32 and the engagement portion abutting surface 32b, which is an inclined surface provided in the lock piece engaging portion 34, and the lock piece abutting surface 34a are provided on the lock piece 32 and the lock piece engaging portion 34. In between, a component force for maintaining the unlocked state is generated.

  As in the above configuration, each contact surface 32b, 34a, which is a portion where the lock piece 32 and the lock piece engaging portion 34 engage with each other, is between the lock piece 32 and the lock piece engaging portion 34. Since it is composed of a slope that generates a component force for maintaining the unlocked state by the spring 33 that is the urging means, the slope piece does not easily move the lock piece 32 from the unlock position. Thereby, it is possible to prevent the slide frame 20 that is a slide member from being unintentionally locked due to vibration or the like when operating the paper feed cassette 1, and the operability of the paper feed cassette 1 is improved.

  Next, a detailed configuration of the lock mechanism 30 of the paper feed cassette 1 according to the third embodiment of the present invention will be described with reference to FIGS. 19 is a top perspective view of the lock piece, FIG. 20 is a bottom perspective view, and FIG. 21 is a side view. FIG. 22 is a vertical sectional view showing the lock portion in the unlocked state of the paper feed cassette, viewed from the downstream side in the paper supply direction. Since the basic configuration of this embodiment is the same as that of the first embodiment described with reference to FIGS. 3 to 15, the components common to the first embodiment are described in the drawings. And the description thereof will be omitted.

  19 to 21, a pin 32 c and a seat protrusion 32 f are provided on the seat portion of the lock piece 32 that receives the end of the spring 33. The pin 32c is provided in parallel with the moving direction of the lock piece 32 (arrow C in FIG. 21). As shown in FIG. 21, the receiving projection 32f protrudes from the main body of the lock piece 32 so as to overlap the upper half of the pin 32c at the base of the pin 32c. The protruding length of the receiving protrusion 32f is shorter than the protruding length of the pin 32c.

  As shown in FIG. 22, when the spring 33 is connected to the receiving portion of the locking piece 32 provided with the pin 32c and the receiving projection 32f, the angle of the end of the spring 33 is changed in the moving direction of the locking piece 32. In contrast, the spring 33 is curved. For this reason, a bending force acts on the spring 33, and the lock piece 32 is biased slightly diagonally downward at a different angle from the horizontal left, which is the moving direction. In order to displace the lock piece 32 to the lock position, the lock piece 32 must be moved upward to release the engagement with the lock piece engaging portion 34. Therefore, a downward force acting on the lock piece 32 is required. This enhances the action of maintaining the unlocked state. In this way, in the unlocked state, the receiving projection 32f provided on the receiving seat for receiving the end of the spring 33 of the locking piece 32 is locked between the locking piece 32 and the locking piece engaging portion 34. Generate a component to maintain the released state.

  As in the above configuration, the spring 33, which is the biasing means, biases the lock piece 32 in a direction that increases the maintenance of the unlocked state of the lock piece 32 at an angle different from the moving direction of the lock piece 32. It is possible to make it easier for the piece 32 to stay in the unlocked position. Thereby, it is possible to suppress the slide frame 20 that is a slide member from being locked unintentionally due to vibration or the like when operating the paper feed cassette 1, and to improve the operability of the paper feed cassette 1. .

  Further, the spring 33 as the urging means is constituted by a compression coil spring, and generates a component force for maintaining the unlocked state by setting the angle and / or position of the receiving seat that receives the end thereof. By devising and designing, it is possible to easily change the urging direction of the lock piece 32 and strengthen the maintenance of the unlocked state of the lock piece 32.

  In addition, since the seat of the lock piece 32 that receives the end of the spring 33 is provided with a seat projection 32f that changes the axial direction of the spring 33 to an angle different from the moving direction of the lock piece 32, the seat projection Only by providing 32f in the connection part with the spring 33 of the lock piece 32, the spring 33 can generate | occur | produce the component force of a lock release state maintenance easily.

  Next, a detailed configuration of the lock mechanism 30 of the paper feed cassette 1 according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 23 is a vertical sectional view showing the lock portion of the paper feed cassette in the unlocked state, as viewed from the downstream side in the paper supply direction. Since the basic configuration of this embodiment is the same as that of the first embodiment described with reference to FIGS. 3 to 15, the components common to the first embodiment are described in the drawings. And the description thereof will be omitted.

  In FIG. 23, a receiving seat 16 is provided at a portion of the main frame 10 that is a main body that receives an end portion of the spring 33. The contact surface of the end portion of the spring 33 of the seat 16 is formed as an inclined surface such that the end portion on the opposite side of the spring 33, that is, the end portion on the lock piece 32 side of the spring 33 faces upward.

  As shown in the figure, when the spring 33 is connected between the main frame 10 and the lock piece 32, the spring 33 is bent and attached under the influence of the inclined surface of the seat 16. For this reason, a bending force acts on the spring 33, and the lock piece 32 is biased slightly diagonally downward at a different angle from the horizontal left, which is the moving direction. In this way, in the unlocked state, the seat 16 constituted by the inclined surface that receives the end of the spring 33 of the main frame 10 is in the unlocked state between the lock piece 32 and the lock piece engaging portion 34. Generate maintenance force.

  Since the seat 16 that receives the end of the spring 33 of the main frame 10 that is the main body is configured with a slope that changes the axial direction of the spring 33 to an angle different from the moving direction of the lock piece 32 as in the above configuration. By simply providing the inclined surface at the connecting portion with the spring 33 of the main frame 10, a component force for maintaining the unlocked state can be easily generated in the spring 33.

  In the above embodiment, the slide frame 20 moves in the paper supply direction. However, the slide frame 20 may move in the paper width direction perpendicular to the paper supply direction. Two locking mechanisms 30 are provided on the left and right sides from the central portion in the paper width direction, but only one of them may be provided. In addition, the lock grooves are provided at three locations and the paper feed cassette 1 can be reduced / expanded in three stages, but the number of lock grooves is not limited to three.

  Although the embodiment of the present invention has been described above, various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used in all sheet cassettes that can be reduced / expanded according to the sheet size.

These are the perspective views of the paper feed cassette which concerns on embodiment of this invention, and show a reduction state. These are the perspective views of the paper feeding cassette which concerns on embodiment of this invention, and show an expanded state. These are the partial expansion perspective views of the paper feed cassette concerning a 1st embodiment of the present invention, and showing an expansion state. FIG. 4 is a vertical partial cross-sectional view of a lock groove and a slope of the paper feed cassette shown in FIG. 3. FIG. 4 is a top perspective view of the lock piece shown in FIG. 3. FIG. 4 is a bottom perspective view of the lock piece shown in FIG. 3. FIG. 4 is a partially enlarged perspective view of the paper feed cassette similar to FIG. 3 and shows a reduced state. These are the horizontal cross-sectional perspective views which show the lock part of FIG. 7, and show a locked state. Fig. 8 is a vertical sectional view showing the lock portion of Fig. 8 as viewed from the downstream side in the paper supply direction. These are the horizontal cross-sectional perspective views which show the lock part of FIG. 7, and show a lock release state. FIG. 11 is a partially enlarged perspective view showing the lock piece engaging portion of FIG. 10. Fig. 10 is a vertical sectional view showing the lock portion of Fig. 10 as viewed from the downstream side in the paper supply direction. Fig. 7 is a partially enlarged perspective view of the paper feed cassette similar to Fig. 7 and shows a state during expansion. Fig. 13 is a vertical sectional view showing the lock portion of Fig. 13 as viewed from the downstream side in the paper supply direction. FIG. 9 is a partially enlarged perspective view of the paper feed cassette locked at a second lock groove position. These are the upper surface perspective views of the lock piece of the paper feed cassette concerning a 2nd embodiment of the present invention. FIG. 17 is a side view of the lock piece shown in FIG. 16. These are vertical sectional views showing the lock portion in the unlocked state of the paper feed cassette, as viewed from the downstream side in the paper supply direction. These are the top perspective views of the lock piece of the paper feed cassette concerning a 3rd embodiment of the present invention. FIG. 20 is a bottom perspective view of the lock piece shown in FIG. 19. FIG. 20 is a side view of the lock piece shown in FIG. 19. These are vertical sectional views showing the lock portion in the unlocked state of the paper feed cassette, as viewed from the downstream side in the paper supply direction. These are vertical sectional views showing the lock portion in the unlocked state of the paper feed cassette according to the fourth embodiment of the present invention, as seen from the downstream side in the paper supply direction.

Explanation of symbols

1 Paper cassette 10 Main frame (main unit)
13 Lock piece storage 16 Receiving seat 20 Slide frame (slide member)
23 Locking piece sliding surface 24 Step 30 Locking mechanism 31 Locking groove 32 Locking piece 32a Operation part 32b Engagement part contact surface 32c Pin 32d Support protrusion 32f Seating protrusion 33 Spring (biasing means)
34 Lock piece engaging portion 34a Lock piece contact surface 35 Slope

Claims (7)

A main body, a slide member that engages with the main body and is movable according to the paper size, and a lock mechanism that is provided between the main body and the slide member and locks the movement of the slide member,
The lock mechanism includes a plurality of lock grooves whose positions are shifted in the movement direction of the slide member, a lock piece that moves in a direction perpendicular to the movement direction of the slide member and engages with the lock groove, and the lock piece An urging means for urging the locking position; an engaging portion that engages with the locking piece displaced against the urging means; And a slope that contacts the lock piece when the slide member is moved and releases the lock piece from the engaging portion.   The main body is a main frame that supports the downstream side in the paper supply direction, and the slide member engages with the main frame to support the upstream side in the paper supply direction, and in the paper supply direction according to the paper size. 2. The paper feed cassette according to claim 1, wherein the paper feed cassette is a movable slide frame, and the lock mechanism is provided at a portion where the main frame and the slide frame overlap each other.   The portion where the lock piece and the engagement portion engage with each other is configured by an inclined surface that generates a component force for maintaining the unlocked state by the biasing means between the lock piece and the engagement portion. The sheet feeding cassette according to claim 1, wherein the sheet feeding cassette is characterized by the following.   3. The biasing means according to claim 1, wherein the biasing means biases the lock piece in a direction that strengthens the maintenance of the unlocked state of the lock piece and changes an angle from the moving direction of the lock piece. Paper cassette.   The said urging | biasing means is comprised with a compression coil spring, and produces | generates the component force of the said unlocking state maintenance by the angle setting and / or position setting of the receiving seat which receives the edge part. Paper cassette.   The protrusion that changes the axial direction of the compression coil spring to an angle different from the moving direction of the lock piece is provided on the seat that receives the end of the compression coil spring of the lock piece. 5. The paper feed cassette according to 5.   The said seat which receives the edge part of the said compression coil spring of the said main body is comprised by the inclined surface which changes the axial direction of a compression coil spring into the angle different from the moving direction of the said lock piece. The paper cassette described in 1.

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