Pinch roller mechanism for plotter

Abstract

To provide a pinch roller mechanism for plotter capable of easily positioning a pinch roller.SOLUTION: The mechanism comprises: a rail 9 extending horizontally in a direction intersecting the medium transport direction near the upper part of a working stage 3; a slide member 16 through which the rail 9 passes and which moves horizontally; and a roller support member supported by the slide member 16 for vertical movement. The mechanism comprises: a pinch roller 6 rotatably supported by the roller support member; and a spring member which biases the roller support member downward. The slide member 16 has a window 22 through which the pinch roller 6 is exposed when viewed from diagonally above on the upstream side in the transport direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a pinch roller mechanism of a plotter that urges a pinch roller toward a medium. [Background technology]

[0002] A conventional cutting plotter, as described in Patent Document 1, for example, is equipped with a plurality of pinch rollers for pressing the medium to be cut against the medium driving roller. The position of the pinch roller needs to be changed according to the size of the medium to be cut. For this reason, the conventional pinch roller is configured to be movable in a horizontal direction (hereinafter, this direction will be simply referred to as the "left-right direction") intersecting with the conveying direction of the medium to be cut (hereinafter, this direction will be simply referred to as the "front-rear direction"). When the pinch roller is moved, it needs to be in a state separated from the medium driving roller. A conventional pinch roller mechanism that can artificially switch between a state in which the pinch roller is pressed against the medium driving roller and a state in which the pinch roller is separated from the medium driving roller is described in Patent Document 1, for example.

[0003] The pinch roller disclosed in Patent Document 1 is supported by a rail member extending in the left-right direction via a pinch roller mechanism. This pinch roller mechanism includes a support member disposed below the rail member and supported by the rail member, and an arm member formed to extend in the front-rear direction and supported at the lower end of the support member so as to be swingable up-down. The arm member is supported by the support member at a middle portion in the front-rear direction. A pinch roller is provided at the front end of the arm member, which is the front side of the device, and a drive mechanism is connected to the rear end. The rear end of the arm member is biased upward by a spring member. The drive mechanism is structured to push the rear end of the arm member downward by a cam member operated by a lever operation. When the rear end of the arm member is pushed downward, the pressure by the pinch roller is released.

[0004] The pinch roller mechanism shown in Patent Document 1 is large because the rail member and the pinch roller mechanism are aligned vertically, and furthermore, because it has a structure that uses a cam member to drive the arm member, it has a large number of parts and is costly, making it difficult to adopt in a consumer cutting plotter. An example of a pinch roller mechanism used in a consumer cutting plotter is described in Patent Document 2.

[0005] The pinch roller mechanism disclosed in Patent Document 2 has a shaft member that extends from the left end to the right end of the cutting plotter, and a cylindrical pinch roller member through which the shaft member passes. The pinch roller member has a pinch roller on the same axis. In this pinch roller mechanism, the pressing force for pressing the pinch roller against the media drive roller is transmitted to the pinch roller via the shaft member.

[0006] By adopting the configuration disclosed in Patent Document 2, it is possible to reduce the number of parts compared to adopting the configuration shown in Patent Document 1. However, the pinch roller mechanism described in Patent Document 2 is difficult to adopt in large cutting plotters. The reason for this is that bending occurs in the center part of the shaft member, which weakens the pressing force that presses the pinch roller against the media driving roller. Such problems can be solved to some extent by using a highly rigid rail made of a drawn material instead of a shaft member that is prone to bending, as disclosed in Patent Document 3.

[0007] The pinch roller mechanism disclosed in Patent Document 3 includes a slide member supported on a highly rigid rail made of a drawn material so as to be movable in the left-right direction. A roller support member having a pinch roller is supported on the slide member so as to be movable in the up-down direction. The pinch roller is supported by the roller support member so as to be rotatable. The roller support member is biased downward by a spring member provided between the slide member and the roller support member. The rail is formed in a band shape that is wide in the front-rear direction to increase rigidity, and covers the slide member and the roller support member from above. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 6046998 [Patent Document 2] JP 2017-186109 A [Patent Document 3] JP 2021-195181 A Summary of the Invention [Problem to be solved by the invention]

[0009] The pinch roller mechanism disclosed in Patent Document 1 had the problem that because the pinch roller was hidden under the rail, it was not possible to position the pinch roller so that the desired position on the medium to be cut was pressed by the pinch roller.

[0010] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a pinch roller mechanism for a plotter which improves the visibility of the pinch roller even when a highly rigid rail is used. [Means for solving the problem]

[0011] In order to achieve this object, the pinch roller mechanism of a plotter according to the present invention comprises a rail extending in a horizontal direction intersecting the transport direction of the medium near the upper part of a work stage through which a sheet-like medium is transported, a slide member supported on the rail so as to be movable in the horizontal direction with the rail passing through, a roller support member that moves up and down while supported by the slide member, a pinch roller supported on the roller support member so as to be rotatable with the horizontal direction as its axial direction, a spring member provided between the slide member and the roller support member for biasing the roller support member downward, and a pressure release mechanism having an operating lever supported on the slide member so as to be swingable, the operating force applied to the operating lever pushing the roller support member upward against the spring force of the spring member, and the slide member has a window portion through which the pinch roller is exposed when viewed from diagonally above on the upstream side of the transport direction.

[0012] The present invention may also provide a pinch roller mechanism for the plotter, wherein the roller support member is formed to extend in the transport direction and is supported by the slide member at the center of the transport direction so as to be able to swing freely in the vertical direction, the pinch roller is supported by one end of the roller support member, the spring member urges the one end of the roller support member downward, and the operating lever has a pressing portion that presses the other end of the roller support member downward.

[0013] The present invention may be such that, in the pinch roller mechanism of the plotter, one end of the roller support member is positioned downstream in the transport direction from the other end, the operating lever is formed in a gate shape having a grip portion extending in the horizontal direction and a pair of lever portions having one end connected to both ends of the grip portion, and is configured to be freely swingable between a stored position in which the pair of lever portions are positioned on either side of the window portion and overlapped on the upper end of the slide member, and an operating position in which the grip portion stands away from the slide member, centered around the other end of the lever portions, and the pressing portion is provided on the other end of the operating lever and is configured to press the other end of the roller support member downward when the operating lever is standing in the operating position.

[0014] In the pinch roller mechanism of the plotter of the present invention, the other end of the lever portion and the other end of the roller support member may have a holding structure for holding the operating lever in the operating position.

[0015] In the pinch roller mechanism of the plotter of the present invention, when the operating lever is located in the stored position, the grip portion may be located downstream in the transport direction from the other end of the lever portion.

[0016] In the pinch roller mechanism of the plotter of the present invention, when the operating lever is located in the stored position, the grip portion may be located upstream in the transport direction from the other end of the lever portion. Effect of the Invention

[0017] According to the present invention, it is possible to provide a pinch roller mechanism for a plotter in which the visibility of the pinch roller is high even when a highly rigid rail is used. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a perspective view of a cutting plotter equipped with a pinch roller mechanism according to the present invention. [Diagram 2] FIG. 2 is a side view of the pinch roller unit. [Diagram 3] FIG. 3 is a plan view of the pinch roller unit. [Figure 4] FIG. 4 is a perspective cross-sectional view of the rail. [Diagram 5] FIG. 5 is a perspective view of the pinch roller unit. [Figure 6] FIG. 6 is an exploded perspective view of the pinch roller unit as viewed obliquely from above. [Figure 7] FIG. 7 is an exploded perspective view of the pinch roller unit as viewed obliquely from below. [Figure 8] FIG. 8 is a perspective view of the slide member as viewed obliquely from above. [Figure 9] FIG. 9 is a perspective view of the slide member as viewed obliquely from below. [Figure 10] FIG. 10 is a cross-sectional view taken along line XX in FIG. [Figure 11] FIG. 11 is a perspective cross-sectional view showing a main part of the pinch roller unit in a cutaway view. [Figure 12] FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. [Figure 13] FIG. 13 is a perspective view of the right-side roller support member and the left-side roller support member. [Figure 14] FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. [Figure 15] FIG. 15 is a perspective view of the operating lever. [Figure 16] FIG. 16 is a cross-sectional view of the pinch roller unit showing a state in which the operating lever is located at the operating position. [Figure 17] FIG. 17 is an enlarged cross-sectional view showing a part of the pressure release mechanism. [Figure 18] FIG. 18 is a perspective view of a pinch roller unit according to the second embodiment. [Figure 19] FIG. 19 is a perspective view of the operating lever. [Figure 20] FIG. 20 is a perspective view of the roller support member. [Figure 21] FIG. 21 is a side view of the main part showing a state in which the operating lever is located at the stored position. [Figure 22] FIG. 22 is a side view of the main part, showing a state in which the roller support member is pressed by the operating lever. [Diagram 23] FIG. 23 is a side view of the main part, showing a state in which the operating lever is located at the operating position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] (First embodiment) Hereinafter, one embodiment of a pinch roller mechanism for a plotter according to the present invention will be described in detail with reference to FIGS. The cutting plotter 1 shown in Fig. 1 cuts out figures and characters from a sheet-like medium 2 to be cut (hereinafter simply referred to as the medium 2), and is equipped with a work stage 3 on which the medium 2 is transported, and a pen carriage 4 that supports a cutting pen (not shown). The medium 2 can be a sheet fed type or a rolled sheet.

[0020] (Explanation of the working stage and pen carriage) The work stage 3 is formed to extend in the transport direction of the medium 2 (the direction from the lower left to the upper right in FIG. 1) and in the left-right direction (the direction from the upper left to the lower right in FIG. 1), which is a horizontal direction intersecting the transport direction. In the following, the downstream side in the transport direction of the medium 2 is referred to as the rear side, and the upstream side in the transport direction of the medium 2 is referred to as the front side. As shown in FIG. 2, the medium 2 is conveyed by rotating the medium driving roller 5 while the medium 2 is sandwiched between the medium driving roller 5 and a pinch roller 6.

[0021] The pen carriage 4 has a function of driving a cutting pen (not shown) in the up-down direction, and is configured to be movable in the left-right direction. The up-down direction here refers to a vertical direction that intersects with the work stage 3. The medium 2 is cut by attaching a cutting pen to the pen carriage 4, and while the medium 2 is sandwiched between the medium drive roller 5 and the pinch roller 6, rotating the medium drive roller 5 forward or backward, while inserting the cutting pen into the medium 2 and moving it left and right together with the pen carriage 4.

[0022] (Outline of the pinch roller) The pinch rollers 6 are provided in pinch roller units 7 and 8 depicted at two locations on the left and right sides in Fig. 1 near the work stage 3. For convenience, in what follows, the pinch roller unit located on the right side of Fig. 1 will be referred to as the first pinch roller unit 7, and the pinch roller unit located on the left side will be referred to as the second pinch roller unit 8. These first and second pinch roller units 7 and 8 are supported by rails 9 located near the upper part of the work stage 3.

[0023] The rail 9 constitutes a pinch roller mechanism 11 (see FIG. 2) in cooperation with the first and second pinch roller units 7 and 8. The rail 9 extends in the left-right direction from the left end to the right end of the work stage 3 near the top of the work stage 3, and is fixed to the frame (not shown) of the cutting plotter at both left-right ends.

[0024] (Rail description) The rail 9 is formed of a drawn material having a predetermined cross-sectional shape. As shown in FIG. 4, the rail 9 according to this embodiment is formed so that the cross-sectional shape is a substantially right-angled triangle, and is used in a position in which the inclined surface 9a faces rearward and upward, and the front surface 9b extends in the vertical direction. A first groove 9c extending in the left-right direction is formed on the inclined surface 9a of the rail 9, and a second groove 9d extending in the left-right direction is formed on the front surface 9b. In addition, a third groove 9e extending in the left-right direction is formed at the rear end of the rail 9.

[0025] A plate-like member 12 used to determine the left-right position of the first pinch roller unit 7, which will be described later, is attached to the first groove 9c. A recess 13 is formed on the top surface of this plate-like member 12. The recesses 13 are formed at a plurality of positions aligned at predetermined intervals in the left-right direction. The first pinch roller unit 7, which will be described in detail later, is configured so that when a standard-sized medium 2 is used, the pinch roller 6 is positioned at an optimal position for the medium 2 by fitting a part of the first pinch roller unit 7 into the recess 13.

[0026] 2, first and second engagement pieces 14, 15 provided on a first pinch roller unit 7, which will be described later, engage with the second groove 9d and the third groove 9e. The first and second engagement pieces 14, 15 engage with the second and third grooves 9d, 9e, thereby restricting the first pinch roller unit 7 from coming off upward relative to the rail 9. Although not shown in detail, the second pinch roller unit 8 also engages with the rail 9 in the same way as the first pinch roller unit 7, and is prevented from coming off.

[0027] (Explanation of the pinch roller unit) 5, the first and second pinch roller units 7, 8 are configured by assembling various functional parts to slide members 16, 17 through which rail 9 passes in the left-right direction. The second pinch roller unit 8 only differs in some parts from the first pinch roller unit 7. For this reason, the first pinch roller unit 7 will be described in detail here, and the second pinch roller unit 8 will be described only as necessary.

[0028] As shown in Figures 6 and 8, the slide member 16 of the first pinch roller unit 7 is formed in a rectangular frame shape when viewed from above. In more detail, the slide member 16 is formed of a right arm portion 18 and a left arm portion 19 extending in the front-rear direction while being spaced apart from each other in the left-right direction, a front connector portion 20 connecting the front ends of the right arm portion 18 and the left arm portion 19, and a rear connector portion 21 connecting the rear ends of the right arm portion 18 and the left arm portion 19. A window portion 22 consisting of a rectangular through hole is formed in the center of the slide member 16. A movable side mark 20a is provided on the upper surface of the front connector portion 20.

[0029] As shown in Fig. 3, this movable side mark 20a is formed near the opening of the window portion 22 and at the same position as the pinch roller 6 in the left-right direction. Meanwhile, as shown in Fig. 5, a fixed side mark 23 is provided at the front end of the work stage 3. The fixed side mark 23 serves as a guide for the position of the pinch roller 6 when using a standard-sized medium 2. Since this fixed side mark 23 and the movable side mark 20a provided on the slide member 16 are aligned in the front-rear direction, the pinch roller 6 can be positioned at the optimal position for each medium 2 when using a standard-sized medium 2.

[0030] As shown in Fig. 8, a recess 24 for passing the rail 9 is formed in the lower front portion of the slide member 16. The recess 24 has the above-mentioned first and second engagement pieces 14, 15, and is formed in a shape into which the rail 9 can be movably fitted. Therefore, by fitting the rail 9 into the recess 24, the slide member 16 is supported by the rail 9 so as to be movably movable in the left-right direction with the rail 9 penetrating through the slide member 16 in the left-right direction.

[0031] The first engagement piece 14 is provided to protrude rearward from the front end of the recess 24. The second engagement piece 15 is provided to protrude forward from the rear end of the recess 24. In the slide member 16 used in the first pinch roller unit 7, as shown in Fig. 9, a protrusion 25 is formed in a portion of the recess 24 that faces the inclined surface 9a of the rail 9. This protrusion 25 is formed to fit into the recess 13 of the plate-like member 12 provided on the rail 9. By fitting this protrusion 25 into the recess 13 of the plate-like member 12, resistance increases when the first pinch roller unit 7 moves along the rail 9, and the operator can be given a sense of moderation.

[0032] As shown in Fig. 8, the right arm portion 18 and the left arm portion 19 each have a hollow portion 26 that opens in the vertical direction. A pair of left and right roller support members 27, 28 (see Figs. 6 and 7) for supporting the pinch roller 6 are partially inserted into this hollow portion 26 from below. As shown in Fig. 10, the pinch roller 6 is rotatably supported by a support shaft 31 extending in the left-right direction via a bearing member 32. Both ends of the support shaft 31 are fixed to the roller support members 27, 28. The support shaft 31 in this embodiment is fixed to the roller support members 27, 28 in a state in which it passes through a cylindrical spacer 33. The spacer 33 is used to determine the position of the pinch roller 6 in the left-right direction, and is inserted between the pinch roller 6 and the left roller support member 28.

[0033] The right roller support member 27 and the left roller support member 28 are formed to be symmetrical in the left-right direction and extend in the front-rear direction (medium transport direction). Through holes 34, 35 extending in the left-right direction are formed in the rear ends 27a, 28a of the right roller support member 27 and the left roller support member 28. Both ends of a support shaft 31 supporting the pinch roller 6 are fitted into the through holes 34, 35 and fixed. The fitting portions between the support shaft 31 and the right roller support member 27 and the left roller support member 28 are formed by forming the ends of the support shaft 31 into a D-shaped cross section so that the support shaft 31 does not rotate.

[0034] By attaching the support shaft 31 to the right-side roller support member 27 and the left-side roller support member 28 in this manner, the pinch roller 6 is supported by the rear end portions 27a, 28a of the right-side roller support member 27 and the left-side roller support member 28. In this embodiment, the rear end portions 27a, 28a of the right-side roller support member 27 and the left-side roller support member 28 correspond to "one end portion of the roller support member" in this invention, and the front end portions 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28 correspond to "the other end portion of the roller support member" in this invention.

[0035] The right roller support member 27 and the left roller support member 28 are each supported by the slide member 16 so as to be movable in the up-down direction. More specifically, the right roller support member 27 is formed so as to be insertable from below into the hollow portion 26 of the right arm portion 18. The left roller support member 28 is formed so as to be insertable from below into the hollow portion 26 of the left arm portion 19. A lower support pin 36 (see FIG. 10 ) extending in the left-right direction is fixed to the intermediate portion in the front-rear direction of the right roller support member 27 and the left roller support member 28, which is inserted into the hollow portion 26. The lower support pin 36 attached to the right roller support member 27 is rotatably fitted into a through hole 37 formed in the lower end portion of the right arm portion 18. The lower support pin 36 of the left roller support member 28 is rotatably fitted into a through hole 38 formed in the lower end portion of the left arm portion 19.

[0036] In this manner, the right-side roller support member 27 and the left-side roller support member 28 are each supported on the slide member 16 via the lower support pins 36, so that the pinch roller 6 is supported for free rotation by the right-side roller support member 27 and the left-side roller support member 28 with the horizontal direction as its axial direction, and is supported for free movement in the vertical direction by the slide member 16 via the right-side roller support member 27 and the left-side roller support member 28.

[0037] 11 and 12, a right-side spring member 39 made of a compression coil spring is inserted in a compressed state between the rear end 27a of the right-side roller support member 27 and the rear end 18a of the right arm portion 18. Also, a left-side spring member 40 made of a compression coil spring is inserted in a compressed state between the rear end 28a of the left-side roller support member 28 and the rear end 19a of the left arm portion 19. Therefore, the right-side roller support member 27 and the left-side roller support member 28 are urged downward against the slide member 16 by the right-side spring member 39 and the left-side spring member 40.

[0038] Furthermore, in a state in which the pinch roller 6 is supported by the slide member 16 via the right-side roller support member 27 and the left-side roller support member 28, the pinch roller 6 is disposed below the rear connecting portion 21 of the slide member 16, as shown in Fig. 12. The pinch roller 6 in this position can be seen through the window portion 22 from diagonally above on the upstream side in the conveying direction, as shown in Fig. 5.

[0039] As shown in Fig. 11, the front portion of the right roller support member 27 and the front portion of the left roller support member 28 are formed so as to extend upward and forward from the lower support pin 36. As shown in Fig. 13, the upper end of the front portion of the right roller support member 27 and the upper end of the front portion of the left roller support member 28 are each formed with a substantially flat pressure-receiving surface 41 extending in the front-rear direction, and each is provided with a protrusion 42 protruding upward from the pressure-receiving surface 41. In addition, a recess 43 is formed in the pressure-receiving surface 41. The recess 43 is formed at the front end of the right roller support member 27 and the front end of the left roller support member 28 so as to open upward and forward, and has a vertical wall 44 that extends in the left-right and up-down directions and faces forward.

[0040] The pressure receiving surfaces 41 and the protrusions 42 of the right-side roller support member 27 and the left-side roller support member 28 used in the first pinch roller unit 7 constitute a part of a pressure release mechanism 45 (see FIG. 14) described later. The pressure release mechanism 45 is for releasing the state in which the pinch roller 6 presses the medium driving roller 5. The pressure release mechanism 45 is composed of the pressure receiving surface 41 and the protrusion 42 described above, and an operating lever 46 provided on the slide member 16 of the first pinch roller unit 7.

[0041] As shown in Figs. 15(A) to (C), the operating lever 46 is formed in a gate shape having a gripping portion 46a extending in the left-right direction and a pair of lever portions 46b, 46c whose one ends are connected to both ends of the gripping portion 46a. Fig. 15(A) is a perspective view of the operating lever 46 seen from diagonally above the front, Fig. 15(B) is a perspective view of the operating lever 46 seen from diagonally below the rear, and Fig. 15(C) is an enlarged perspective view of the front end portion of the lever portion 46b. As shown in Fig. 5, the lever portions 46b, 46c are disposed on both the left and right sides of the window portion 22 of the slide member 16. The other ends of the lever portions 46b, 46c are positioned above the front ends 27b, 28b of the right roller support member 27 and the left roller support member 28, and are supported by the right arm portion 18 and the left arm portion 19 of the slide member 16 by the upper support pins 47, respectively, so as to be freely swingable.

[0042] The upper support pin 47 extends in the left-right direction and penetrates the other ends of the lever portions 46b and 46c and is fixed thereto. Both ends of the upper support pin 47 are rotatably fitted into through holes 48 formed in the right arm portion 18 and the left arm portion 19 of the slide member 16. The operating lever 46 according to this embodiment can swing about the upper support pin 47 and is configured to be able to take a stored form in which the grip portion 46a falls backward and overlaps with the upper end of the slide member 16 as shown in Figs. 5 and 14, and an upright form in which the grip portion 46a stands up and moves upward away from the slide member 16 as shown in Fig. 16. When this operating lever 46 takes the stored form, the grip portion 46a overlaps with the rear connecting portion 21 of the slide member 16. In the following, the position of the operating lever 46 in the stored form is referred to as the "storage position", and the position of the operating lever 46 in the upright form is referred to as the "operating position".

[0043] As shown in FIG. 15C, a pressing portion 51 is provided at the other end of the operation lever 46. The pressing portion 51 is for pressing the front end 27b of the right roller support member 27 and the front end 28b of the left roller support member 28 downward. The pressing portion 51 according to this embodiment is composed of a pair of left and right pressing plates 52 extending downward and forward from the upper support pin 47 (through hole 48) when the operation lever 46 is in the stored form. The pressing plate 52 is formed with a lower surface 52a parallel to the upper surface of the operation lever 46 in the stored form, and a pressing surface 52b extending upward from the front end of the lower surface 52a. A recess 53 is formed in the middle part of the pressing surface 52b. The boundary between the lower surface 52a and the pressing surface 52b is formed by a curved surface 52c having a predetermined curvature.

[0044] 16 from the stored position shown in Fig. 14, the curved surface 52c comes into contact with the pressure receiving surface 41 and the protrusion 42 formed on the front end portions of the right-side roller support member 27 and the left-side roller support member 28 from above. When the operation lever 46 is further swung in the upright direction with the curved surface 52c in contact with the pressure receiving surface 41 and the protrusion 42, the front end portions 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28 are pressed downward by the pressure plate 52. At this time, the rear end portions 27a, 28a of the right-side roller support member 27 and the left-side roller support member 28 move upward against the spring forces of the spring members 39, 40, and the pinch roller 6 moves upward away from the medium driving roller 5.

[0045] That is, the pressing force release mechanism 45 pushes the rear ends 27a, 28a of the right roller support member 27 and the left roller support member 28 upward against the spring forces of the spring members 39, 40 by the operating force applied to the operating lever 46. The distance between the curved surface 52c and the upper support pin 47 is shorter than the distance between the upper support pin 47 and the gripping portion 46a. Therefore, when gripping and pulling up the gripping portion 46a so that the pressing plate 52 presses the right roller support member 27 and the left roller support member 28, the pressing plate 52 can be easily operated using the principle of leverage.

[0046] 16, the pressing surface 52b of the operating lever 46 is formed so as to overlap with the pressure-receiving surface 41 when the operating lever 46 is in the upright position and reaches the operating position. The recess 53 of the pressure-receiving surface 41 is formed at a position where the protrusion 42 is inserted with the pressing surface 52b overlapping with the pressure-receiving surface 41. When the pressing surface 52b overlaps with the pressure-receiving surface 41 and the protrusion 42 is inserted into the recess 53, the operating lever 46 essentially functions as a support rod, and the right roller support member 27 and the left roller support member 28 are held in that position (the position where the pinch roller 6 is separated from the medium driving roller 5) against the spring forces of the spring members 39, 40.

[0047] That is, the other end having the pressing portion 51 of the operating lever 46 and the front ends 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28 have a holding structure 54 that holds the operating lever 46 in a state in which the operating lever 46 is raised to the operating position in which the operating lever 46 is in an upright form. By holding the operating lever 46 in the operating position in this manner, the slide member 16 can be gripped with one hand and moved left and right along the rail 9.

[0048] As shown in Fig. 15(C), a stopper piece 55 is provided between the pair of pressing plates 52 constituting the pressing portion 51. This stopper piece 55 is for restricting the operating lever 46 from further swinging in a state where it has been swung to the operating position. The stopper piece 55 is formed so as to face the vertical walls 44 formed on the front ends 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28 as shown in Fig. 17 when the operating lever 46 is in the operating position. Therefore, when the operating lever 46 swings beyond the operating position, the stopper piece 55 comes into contact with the vertical wall 44, restricting the operating lever 46 from swinging further.

[0049] Unlike the first pinch roller unit 7, the second pinch roller unit 8 does not include the operation lever 46. The other structures of the second pinch roller unit 8 are the same as those of the first pinch roller unit 7. As shown in FIG. 5, the second pinch roller unit 8 includes a cover 56 instead of the operation lever 46. The cover 56 is fixed to the upper end of the slide member 17.

[0050] (Explanation of operation and effects of the embodiment) When using the cutting plotter 1 having the pinch roller mechanism 11 configured in this manner, first, the pinch roller 6 is placed in a position that matches the width dimension of the medium 2 to be used. At this time, the grip portion 46a of the operation lever 46 of the first pinch roller unit 7 is gripped, and the operation lever 46 is raised to the operation position. By positioning the operation lever 46 in the operation position, the pinch roller 6 is separated upward from the medium driving roller 5 by the pressure release mechanism 45, and the operation lever 46 is held in the raised position by the holding structure 54. This makes it possible to move the first pinch roller unit 7 along the rail 9 with the operation lever 46 released.

[0051] Then, the mark 20a of the first pinch roller unit 7 is aligned with the mark 23 that is the target of the work stage 3. The slide member 16 of the first pinch roller unit 7 has a window 22 through which the pinch roller 6 is exposed when viewed from diagonally above the front side (upstream side in the conveying direction). Therefore, this operation can be performed while viewing the pinch roller 6 through the window 22. When the first pinch roller unit 7 moves to the target position, the protrusion 25 of the slide member 16 fits into the recess 13 provided in the plate-like member 12 of the rail 9, increasing the resistance when moving the first pinch roller unit 7. The recess 13 is installed so that the protrusion 25 fits into it when the pinch roller 6 is located at a pinch roller position that is determined in advance for each size of the medium 2. Therefore, the operator can be informed that the pinch roller position for each size of the medium 2 has been reached.

[0052] At this time, the operator looks at the pinch roller 6 through the window portion 22 and determines whether the pinch roller 6 has reached the desired position. If the pinch roller 6 is not near the edge of the medium, the first pinch roller unit 7 is further advanced. On the other hand, if the pinch roller 6 is at the desired position, the operator tilts the operation lever 46 backward to position it at the storage position. By positioning the operation lever 46 at the storage position, the pressing portion 51 is separated upward from the right roller support member 27 and the left roller support member 28, and the rear end portions 27a, 28a of the right roller support member 27 and the left roller support member 28 are lowered by the spring forces of the spring members 39, 40, and the pinch roller 6 is pressed against the medium driving roller 5.

[0053] Since the rail 9 is formed from a drawn material having higher rigidity than a pipe or the like, the pressing force does not become small even when the pinch roller 6 is located, for example, in the center of the work stage 3 in the left-right direction. Thereafter, the medium driving roller 5 is driven to pinch the medium 2 between the medium driving roller 5 and the pinch roller 6, and position the medium 2 at a predetermined cutting start position. In this state, the medium 2 can be cut by the cutting plotter.

[0054] Thus, according to the pinch roller mechanism 11 of this embodiment, a window portion 22 is formed in the slide member 16 through which the rail 9 passes, so that the pinch roller 6 can be viewed through the window portion 22 without being obstructed by the rail 9. Therefore, even if rails 9 having high rigidity are used, a pinch roller mechanism for a plotter in which the visibility of pinch rollers 6 is high can be provided. The pinch roller mechanism 11 according to this embodiment can be installed near the rail 9 by consolidating multiple functions, such as the mechanism for supporting the pinch roller 6 and the pressure release mechanism 45, and is compact and can be provided at low cost, so that it can be installed in small consumer plotters.

[0055] The operating lever 46 according to this embodiment has a pressing portion 51 that presses the front ends 27b, 28b of the right roller support member 27 and the left roller support member 28 downward. Therefore, the pressure from the pinch roller 6 can be released by directly pressing the right-side roller support member 27 and the left-side roller support member 28 with the operating lever 46, so that no other members such as a cam member are required to release the pressure from the pinch roller 6. Therefore, the number of parts is reduced, making it possible to achieve further miniaturization and cost reduction.

[0056] The operating lever 46 in this embodiment is formed in a gate shape, and by gripping and pulling up the grip portion 46a located in the left-right center with the hand, the right-side roller support member 27 and the left-side roller support member 28 can be pressed by the pressing portion 51 on the opposite side to the grip portion 46a. Therefore, even though the right-side roller support member 27 and the left-side roller support member 28 are pressed against the spring forces of the spring members 39, 40, the lever can be used to easily operate the lever.

[0057] The pinch roller mechanism 11 according to this embodiment has a holding structure 54 that holds the operating lever 46 in the operating position. Therefore, when moving the pinch roller 6, the hand can be released from the operating lever 46, which provides good operability.

[0058] In addition, when the operating lever 46 according to this embodiment is in the stored position, the grip portion 46a is located rearward (downstream in the conveying direction) from the other ends of the lever portions 46b and 46c. Therefore, when raising the operating lever 46, the operator can reach out from the front of the cutting plotter 1 to grip the grip portion 46a and pull it toward himself, which provides good operability.

[0059] (Second embodiment) The pinch roller unit can be configured as shown in FIGS. Pinch roller unit 61 shown in Fig. 18 is made smaller while adopting the same structure as pinch roller unit 7 in the first embodiment shown in Fig. 1 to Fig. 17. For this reason, in this embodiment, parts having the same functions as pinch roller unit 7 are given the same reference numerals even if their shapes are different, and detailed explanations are provided appropriately as necessary. In a pinch roller unit 61 according to this embodiment, the direction in which the operating lever 46 of the pressure release mechanism 45 is operated is different from that of the pinch roller unit 7 according to the first embodiment.

[0060] The operating lever 46 shown in Fig. 18 is configured such that, in the stored state, the gripping portion 46a overlaps from above with the front connecting portion 20 of the slide member 16. As shown in Fig. 19, the pressing portion 51 of this operating lever 46 has a protrusion 62 and a pair of flat surfaces 63 connected to both the left and right sides of the protrusion 62. On the other hand, as shown in Fig. 20, front end portions 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28 in this embodiment have a pressure-receiving surface 41 that faces upward, and a stopper piece 64 that protrudes upward from the front end of the pressure-receiving surface 41. The rear end portions 27a, 28a of the right-side roller support member 27 and the left-side roller support member 28 have the same structure as when the first embodiment is adopted.

[0061] When the operating lever 46 according to this embodiment is in the stored position, the pressing portion 51 is located above the front ends 27b, 28b of the right-side roller support member 27 and the left-side roller support member 28, as shown in Fig. 21. When the gripping portion 46a of the operating lever 46 is pulled upward, the operating lever 46 stands up from the stored position, and the protrusion 62 of the pressing portion 51 presses the pressure-receiving surface 41 downward, as shown in Fig. 22. As the protrusion 62 presses the pressure-receiving surface 41, the pinch roller 6 moves upward away from the medium driving roller 5. Then, by further raising the operating lever 46, the flat surface 63 of the pressing portion 51 overlaps the pressure receiving surface 41, as shown in Fig. 23. In this state, the pinch roller 6 moves downward so that a gap is created between the medium driving roller 5 and the pinch roller 6 through which the medium 2 can pass. In this embodiment, the position of the operating lever 46 when it is raised in this manner is the operating position. When the operating lever 46 is in the operating position, the operating lever 46 is held in the operating position by the holding structure 54 consisting of the flat surface 63 and the pressure receiving surface 41. If the operating lever 46 is operated beyond this operating position, the projection 62 hits the stopper piece 64, and further swinging is restricted.

[0062] In this embodiment, when the operating lever 46 is in the stored position, the grip portion 46a is located forward (upstream in the conveying direction) of the other ends of the lever portions 46b and 46c. By adopting this configuration, the slide member 16 can be formed compactly in the front-rear direction while ensuring that the length of the lever portions 46b, 46c of the operating lever 46 is a necessary and sufficient length. Note that there is a limit to how short the length of the lever portions 46b, 46c of the operating lever 46 can be made, since this affects operability. For this reason, when forming the slide member 16 short in the front-rear direction to make it compact, if the operating lever 46 is installed so that the grip portion 46a is located on the rear side in the stored state, as in the case of adopting the first embodiment, there is a risk that the grip portion 46a will protrude rearward from the slide member 16.

[0063] The rear of the slide member 16 is the path along which the pen carriage 4 moves in the left-right direction. If the grip 46a protrudes rearward from the slide member 16, it will be difficult to ensure a sufficient clearance between the pinch roller unit and the path of movement. For this reason, by installing the operation lever 46 so that the grip 46a of the operation lever 46 in the stored position is located on the front side, it is possible to make the slide member 16 more compact while ensuring a sufficiently wide clearance with the path of movement of the pen carriage 4.

[0064] Although the above-mentioned first and second embodiments show examples in which the present invention is applied to a cutting plotter, the present invention can also be applied to a pen plotter that draws characters and pictures on a sheet-like medium. [Explanation of symbols]

[0065] DESCRIPTION OF THE REFERENCE NUMERALS 1...cutting plotter, 2...medium, 3...working stage, 6...pinch roller, 9...rail, 11...pinch roller mechanism, 16...slide member, 22...window portion, 27...right-side roller support member, 28...left-side roller member, 39, 40...spring members, 45...pressure release mechanism, 46...operating lever, 46a...grip portion, 46b, 46c...lever portion, 51...pressure portion, 54...holding structure.

Claims

1. a rail extending in a horizontal direction intersecting a conveying direction of the sheet-like medium in the vicinity of an upper portion of a work stage along which the sheet-like medium is conveyed; a slide member supported on the rail so as to be movable in the horizontal direction with the rail passing through the slide member; a roller support member that moves in a vertical direction while being supported by the slide member; a pinch roller rotatably supported by the roller support member with the horizontal direction as its axial direction; a spring member provided between the slide member and the roller support member for biasing the roller support member downward; a pressure release mechanism having an operation lever supported on the slide member so as to be able to swing freely, and for pushing up the roller support member against the spring force of the spring member by an operation force applied to the operation lever; Equipped with 11. A pinch roller mechanism for a plotter, wherein the slide member has a window through which the pinch roller is exposed when viewed from diagonally above on the upstream side in the transport direction.

2. 2. The pinch roller mechanism of claim 1, the roller support member is formed to extend in the transport direction, and is supported by the slide member at a center portion in the transport direction so as to be swingable in the up-down direction, The pinch roller is supported on one end of the roller support member, The spring member biases the one end of the roller support member downward, 4. A pinch roller mechanism for a plotter, wherein the operating lever has a pressing portion for pressing the other end of the roller support member downward.

3. 3. The pinch roller mechanism of claim 2, the one end of the roller support member is positioned downstream in the transport direction from the other end of the roller support member, The operating lever is formed in a gate shape having a grip portion extending in the horizontal direction and a pair of lever portions having one end connected to both ends of the grip portion, and is configured to be freely swingable between a storage position in which the pair of lever portions are positioned on either side of the window portion and overlap the upper end portion of the slide member, and an operating position in which the grip portions stand upright and away from the slide member, centered around the other end portion of the lever portions; a pressing portion provided at the other end of the operating lever and configured to press the other end of the roller support member downward when the operating lever is upright in the operating position.

4. 4. The pinch roller mechanism of claim 3, a roller support member that supports the operation lever at the operation position and the other end of the lever portion and the other end of the roller support member are provided with a holding structure for holding the operation lever at the operation position;

5. 4. The pinch roller mechanism of claim 3, 2. A pinch roller mechanism for a plotter, wherein when the operating lever is in the stored position, the grip portion is located downstream in the transport direction from the other end of the lever portion.

6. 4. The pinch roller mechanism of claim 3, 2. A pinch roller mechanism for a plotter, wherein when the operating lever is in the stored position, the grip portion is located upstream of the other end of the lever portion in the transport direction.

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