Thermal printer and lock mechanism

Abstract

A thermal printer S100 comprises a housing 10, a head cover 20, and a lock mechanism 50. The lock mechanism 50 includes a lever member 30 and a lock member 40. The lever member 30 and the lock member 40 are configured such that the lock member 40 rotates in a direction in which a claw 43 separates from a lock pin P1 as a result of an operation part 31 being pressed down and is unlocked due to the claw 43 detaching from the lock pin P1, and such that the lock member 40 is pressed by a portion of the lever member 30 due to the operation part 31 of the lever member 30 being pulled up, and thereby the lock member 40 is rotated in a direction in which the claw 43 separates from the lock pin P1 and is unlocked due to the claw 43 detaching from the lock pin P1.

Description

Thermal printer and locking mechanism

[0001] The present invention relates to a thermal printer and a locking mechanism.

[0002] Conventionally, printers are incorporated as output devices in kiosk terminals, POS terminals, and ticket issuing machines. Patent Document 1 discloses a structure in the printer's printing mechanism in which paper pulled from a roll is sandwiched between a housing and a cover. Conventionally, this type of printer is provided with a mechanism for locking the cover to the housing when paper is set. Operating the lever of this mechanism releases the lock and allows the cover to open.

[0003] JP 2013-233690 A

[0004] However, the conventional configuration has the problem that it is difficult to perform the operation to release the lock.

[0005] The present invention has been made in consideration of these points, and has as its object to provide a thermal printer and a locking mechanism that make it easy to unlock an openable and closable cover member.

[0006] In a first aspect of the present invention, a printer includes a thermal head that prints on long paper pulled out from a roll, a platen roller that is disposed on the opposite side of the thermal head with the paper sandwiched therebetween and that transports the paper, a housing that holds the platen roller so that the platen roller can rotate, a cover that holds the thermal head and is connected to the housing so as to be able to open and close with one side in the width direction of the paper as a fulcrum, and is provided so as to be movable between a closed position where the thermal head abuts against the platen roller and an open position where the thermal head is separated from the platen roller, and a locking mechanism that locks the cover to the housing, wherein the locking mechanism is comprised of a lever member that is rotatably supported by the cover and has an operating portion formed thereon that is operated by an operator, and a locking mechanism that is rotatably connected to the housing. and a locking member supported by a support mechanism and having a pawl formed thereon that engages with a locking pin of the cover, the pawl engaging with the locking pin to maintain the cover in the closed position, wherein the lever member and the locking member are configured such that, when the operating portion is pushed down, the locking member rotates in a direction in which the pawl moves away from the locking pin, and the lock is released when the pawl disengages from the locking pin, and when the operating portion of the lever member is pulled up, a first abutment portion that is a part of the lever member presses the locking member, thereby rotating the locking member in a direction in which the pawl moves away from the locking pin, and the lock is released when the pawl disengages from the locking pin.

[0007] The thermal printer of the present invention may further include a biasing member that applies a biasing force to the cover in a direction to open the cover, and that pops up the cover when the lock is released.

[0008] In the closed position, the portion of the lever member is located between the locking member and the cover, and the lever member and the locking member may be configured such that when the operating part is pulled up and the lever member rotates, the first abutment portion pushes the locking member in a direction that moves the claw away from the locking pin, thereby causing the claw to disengage from the locking pin.

[0009] The lever member may be configured to rotate around the lock pin, and the distance from the center of the lock pin to the end of the operating portion may be longer than the distance from the center of the lock pin to the first abutment portion.

[0010] The claws may include a first claw that engages with a first position in the longitudinal direction of the locking pin and a second claw that engages with a second position in the longitudinal direction of the locking pin, and the first abutment portion may be formed at the tip of an extension portion that extends at a position between the first claw and the second claw.

[0011] The lever member may have a second abutment portion that abuts against the locking member when the operating portion is pushed down, and the lever member and the locking member may be configured such that when the operating portion is pushed down and the lever member rotates, the locking member is pushed by the second abutment portion, thereby rotating the locking member and disengaging the claw from the locking pin.

[0012] The locking pin may extend in the paper transport direction, and the locking member may have an inclined surface against which the locking pin, which moves toward the locking member when the cover is pushed down, presses, and when the cover is pushed down with the locking pin in contact with the inclined surface, the locking pin slides along the inclined surface, thereby rotating the locking member in a direction that moves the claw away from the locking pin, and when the cover is pushed down further, the claw may engage with the locking pin.

[0013] The locking member may have a support portion supported by a support pin provided on the side of the housing, the claw provided above the support portion, and a spring holding portion provided below the support portion, and a compression spring may be arranged between the spring holding portion and the side of the housing, and the compression spring may urge the locking member in a direction in which the claw is pressed against the locking pin.

[0014] The support pin may extend in a direction parallel to the paper transport direction, and the spring holding portion may include a first spring holding portion located on one end side of the support pin and a second spring holding portion located on the other end side of the support pin.

[0015] The lock pin and the support pin may be arranged parallel to each other, and the pawl may engage above the lock pin when the cover is in the closed position.

[0016] The operating portion may be located at one end of the cover along the periphery of the top surface of the cover.

[0017] In a second aspect of the present invention, in a printing device including a housing that holds one of a thermal head and a platen roller that print on paper, and a cover that holds the other of the thermal head and the platen roller and is connected to the housing so as to be able to open and close around one side in the width direction of the paper as a fulcrum, a locking mechanism that locks the cover to the housing includes a lever member that is rotatably supported on the cover and has an operating portion that is operated by an operator, and a locking member that is rotatably supported on the housing and has a claw that engages with a locking pin of the cover, and the claw engages with the locking pin. and a locking member that maintains the cover in a closed position by pressing the operating portion down, wherein the lever member and the locking member are configured such that, when the operating portion is pushed down, the locking member rotates in a direction in which the claw moves away from the locking pin, and the lock is released when the claw disengages from the locking pin, and when the operating portion of the lever member is pulled up, a part of the lever member presses the locking member, thereby rotating the locking member in a direction in which the claw moves away from the locking pin, and the lock is released when the claw disengages from the locking pin.

[0018] A locking mechanism of one form of the present invention is a locking mechanism that locks a second member to a first member, comprising: a lever member rotatably supported on the second member and having an operating portion formed thereon that is operated by an operator; and a locking member rotatably supported on the first member and having a pawl formed thereon that engages with a first axis of the second member, the locking member maintaining the second member in a locked position by the pawl engaging with the first axis. The lever member and the locking member are configured so that (i) when the operating portion of the lever member moves in a first direction from a locked state in which the pawl is engaged with the first axis, the locking member rotates in a direction in which the pawl moves away from the first axis, and the pawl disengages from the first axis, thereby releasing the lock; and (ii) when the operating portion of the lever member moves in a second direction opposite to the first direction, a part of the lever member presses the locking member, thereby rotating the locking member in a direction in which the pawl moves away from the first axis, and the pawl disengages from the first axis, thereby releasing the lock.

[0019] The present invention provides a thermal printer and a locking mechanism that allow an easy operation to unlock an openable and closable cover member.

[0020] FIG. 1 is a perspective view showing the configuration of a thermal printer according to one embodiment of the present invention. FIG. 1 is a view seen from the front side with the head cover open. FIG. 2 is a schematic representation of FIG. 2. FIG. 1 is a perspective view showing the peripheral structure of the locking mechanism. FIG. 12 is an enlarged view showing the peripheral structure of the locking mechanism. FIG. 13 is a perspective view of a lever member. FIG. 14 is a perspective view of a locking member. FIG. 15 is a view for explaining the locking operation of the locking mechanism. FIG. 16 is a view for explaining a first unlocking operation. FIG. 17 is a view for explaining a second unlocking operation. FIG. 18 is a view showing a modified example of the locking mechanism. FIG. 19 is a view for schematically showing another example of use of the locking mechanism according to the present invention. FIG. 20 is a schematic view showing another example of the configuration of the example of FIG.

[0021] An embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a perspective view showing the configuration of a thermal printer according to an embodiment of the present invention. FIG. 2 is a view from the front with the head cover open. FIG. 3 is a schematic diagram of FIG. 2. FIG. 1 illustrates only the main components of the thermal printer. In the following description, terms indicating directions such as "up," "down," "left," and "right" are used to correspond to the orientations of objects shown in the drawings, but these terms are not intended to limit the scope of the present invention.

[0022] 1, the thermal printer S100 of this embodiment includes, as its main components, a housing 10, a head cover 20, and a locking mechanism 50. The thermal printer S100 is built into, for example, a KIOSK terminal or a POS terminal. The thermal printer S100 is a printing device that prints on a long sheet of paper S pulled out from a roll (not shown).

[0023] The thermal printer S100 also includes a roll holder that holds the roll, a paper cutting mechanism that cuts the printed paper, and a control device that controls the operation of each part, etc. These can be conventionally known devices, so a description thereof will be omitted.

[0024] (Housing 10) The housing 10 is formed in a box shape. The housing 10 is placed on a base member 18 (see FIG. 1) that forms the bottom of the thermal printer S100. Inside the housing 10, a platen roller 15 (see FIG. 3) is rotatably held, and mechanisms and motors for rotating the platen roller 15 are also placed.

[0025] When the paper S is set in the thermal printer S100, the platen roller 15 is located on the opposite side of the paper S from the thermal head 25 (described in detail below). The platen roller 15 is a roller made of an elastic material such as rubber. The platen roller 15 is positioned to extend in a direction perpendicular to the longitudinal direction of the paper S (the left-right direction in FIG. 3). The platen roller 15 is rotated by power from a motor (not shown). The platen roller 15 presses the print surface of the paper toward the thermal head 25 and transports the paper by rotating. The paper S transported by the platen roller 15 is ejected from the front side of the housing 10 (see FIG. 1).

[0026] A support pin P2 is provided on the side surface of the housing 10. The support pin P2 extends in a direction parallel to the direction in which the paper S is transported.

[0027] (Head cover 20) The head cover 20 is a cover disposed to cover the upper part of the housing 10. As shown in Fig. 3, the head cover 20 is a member that supports the thermal head 25 via a heat sink. Specifically, the head cover 20 supports the thermal head 25 so that the thermal head 25 extends in the width direction of the paper S.

[0028] The thermal head 25 has a plurality of heating elements (not shown) arranged in the width direction of the paper. A conventionally known thermal head can be used as the thermal head 25, and a detailed description thereof will be omitted. The thermal head 25 is controlled by a control device (not shown). Specifically, the thermal head 25 prints on the paper by causing the plurality of heating elements to generate heat in response to control signals sent by the control device.

[0029] The head cover 20 is connected to the housing 10 via a connecting pin 11 provided on one side of the housing 10 in the width direction (one side of the paper S in the width direction). The head cover 20 is configured to be openable and closable relative to the housing 10. The head cover 20 is provided so as to be movable between an open position and a closed position, with the connecting pin 11 as a fulcrum. FIG. 1 shows the state in which the head cover 20 is in the closed position. In this state, the thermal head presses against the platen roller via the paper S. The heating elements of the thermal head 25 apply heat to the paper S, thereby printing predetermined letters, numbers, figures, images, etc. on the paper S.

[0030] 2 and 3, when the head cover 20 is in the open position, the thermal head 25 is separated from the platen roller 15. To position the head cover 20 in the open position shown in FIGS. 2 and 3, a biasing member (not shown) is provided that applies a biasing force to the head cover 20 in a direction that causes the head cover to open. The biasing member may be, for example, a torsion spring disposed near the connecting pin 11. The torsion spring may be disposed with the connecting pin 11 threaded through it. Due to the action of this torsion spring, the head cover 20 springs up when the locking mechanism 50 is released.

[0031] As shown in Figure 2, the head cover 20 has a lock pin P1. The lock pin P1 is provided at the end opposite the connecting pin 11. The lock pin P1 is arranged parallel to the connecting pin 11 and the support pin P2, and extends in the paper transport direction. The lock pin P1 is a round bar-shaped pin with which the claw of a lock member 40 of the lock mechanism 50, which will be described later, engages. The lock pin P1 and the support pin P2 are parallel to each other.

[0032] (Locking mechanism 50) The locking mechanism 50 will be described in detail below. Fig. 4 is a perspective view showing the structure surrounding the locking mechanism. Fig. 5 is an enlarged view showing the structure surrounding the locking mechanism. Fig. 6 is a perspective view of the lever member. Fig. 7 is a perspective view of the locking member. Some of the components of the thermal printer have been omitted from Fig. 4 to make the configuration easier to understand.

[0033] The locking mechanism 50 is a mechanism for locking the head cover 20 to the housing 10. In the locked state, the locking mechanism 50 maintains the head cover 20 in the closed position. The locking mechanism 50 has a lever member 30 and a locking member 40. The lever member 30 and the locking member 40 are, for example, molded resin products. The lever member 30 and the locking member 40 may be made of metal or hard rubber.

[0034] The locking mechanism 50 is one of the distinctive features of the thermal printer S100. The locking mechanism 50 is configured so that the lock can be released by both pushing down and pulling up the operating portion 31 (described in detail below) of the lever member 30. Depending on the shape of the terminal in which the thermal printer S100 is incorporated, a configuration that allows the lock to be released only by pulling up the operating portion 31 of the lever member 30 can be problematic, making operation difficult. However, with the configuration of this embodiment, the lock can be released by either pushing down or pulling up the operating portion 31, improving operability.

[0035] 4 and 5, the lever member 30 is supported by a lock pin P1 of the head cover 20 and is provided so as to be rotatable about the lock pin P1. In the locked state, the lever member 30 is attached to the head cover 20 in such a position that an operating portion 31 (described in detail later) extends horizontally.

[0036] A biasing force of a spring S2 (see FIG. 4 ) threaded through the lock pin P1 is applied to the lever member 30. The spring S2 is, for example, a torsion spring. When the operating portion 31 is pressed down, the lever member 30 rotates clockwise (see FIG. 5 ) around the lock pin P1 against the biasing force of the spring S2. The spring S2 has the function of returning the lever member 30, which has rotated clockwise when the operating portion 31 is pressed downward, to its original position as shown in FIG. 4 . The spring S2 or another biasing member may be configured to return the lever member 30, which has rotated counterclockwise when the operating portion 31 is pulled upward, to the position shown in FIG. 4 .

[0037] 6, the lever member 30 has an operating portion 31 and an extending portion 33. The lever member 30 is formed in a generally L-shape as a whole.

[0038] The operating unit 31 is a plate-like portion operated by the operator. As can be seen from FIG. 1 , the operating unit 31 is provided around the upper surface of the head cover 20 when the lever member 30 is attached to the head cover 20 (when the head cover 20 is in the closed position). Specifically, the operating unit 31 is provided at one end of the head cover 20. For example, the operating unit 31 extends at the same height as or approximately the same height as the upper surface of the head cover 20. The operating unit 31 may be provided at a higher or lower position than the upper surface of the head cover 20. In the state shown in FIG. 1 , the operating unit 31 extends, for example, in a direction perpendicular to the height direction of the thermal printer S100. Providing the operating unit 31 in such a position is advantageous in that it is easy for the operator to operate the operating unit 31. The upper surface of the operating unit 31 may be flat. The operating unit 31 may have a concave upper surface that is curved. The operating unit 31 may have a convex upper surface.

[0039] As shown in Fig. 6(b) , the operating portion 31 includes an abutment surface 31a. The abutment surface 31a is provided on the lower surface of the operating portion 31. The abutment surface 31a, which will be described in detail later, is a portion that abuts against a part of the locking member 40 when the operating portion 31 is pressed down. This abutment portion corresponds to the "second abutment portion" of the present invention.

[0040] As shown in FIG. 6( b), the extension portion 33 is provided below the operating portion 31. In this example, the extension portion 33 extends in a direction perpendicular to the operating portion 31. A through hole 33h through which the lock pin P1 is inserted is formed in the extension portion 33. The lever member 30 is supported by the lock pin P1 inserted through the through hole 33h and is rotatable around the lock pin P1. As shown in FIG. 6( a), the extension portion 33 has multiple protrusions 33a formed thereon. The protrusions 33a abut against the side surface of the housing 10. In this example, multiple protrusions 33a are provided, but only one protrusion 33a may be provided. The extension portion 33 extends between one claw 43 (details below) and the other claw 43 of the locking member 40. The tip of the extension portion 33 is an abutment portion that is pressed against a portion of the locking member 40 when unlocked.

[0041] 5, the locking member 40 is supported by a support pin P2 and is rotatable around the support pin P2. As shown in FIGS. 7(a) and 7(b), the locking member 40 has a support portion 41, a claw 43, and a spring holding portion 45.

[0042] The support portion 41 has a through hole 41h through which the support pin P2 passes. The support portion 41 is supported by the support pin P2.

[0043] The claw 43 is located above the support portion 41. The claw 43 is a portion that hooks onto and engages with the lock pin P1. The claw 43 has an inclined surface 43a and an upper surface 43b. The support portion 41 is provided so as to protrude from a portion that constitutes the side surface of the locking member 40. In this embodiment, as shown in FIG. 7( a), a pair of claws 43 is provided. One claw 43 (first claw) is a claw that engages with the lock pin P1 at a first position in the longitudinal direction. The other claw 43 (second claw) is a claw that engages with the lock pin P1 at a second position in the longitudinal direction. In this configuration, when the extension portion 33 (the tip of the extension portion 33 is the abutment portion) for moving the locking member 40 is located between the two claws 43, a pressing force is applied to the position between the two claws 43. Therefore, for example, compared to a configuration in which pressing is performed at a position other than the position between the two claws 43, each claw 43 can be more easily disengaged from the lock pin P1. In other words, it is unlikely that one of the claws 43 will be disengaged from the lock pin P1 while the other claw 43 will not be disengaged from the lock pin P1.

[0044] The inclined surface 43a, which will be described in detail later, is a portion against which the lock pin P1, which moves toward the locking member 40 when the head cover 20 is pushed down, presses. The inclined surface 43a is inclined in a direction that generates a force in a direction that causes the claw 43 to disengage from the lock pin P1 when the lock pin P1 presses against the inclined surface 43a. The inclined surface 43a may be a flat surface or a curved surface, but in this example, the inclined surface 43a is a flat surface.

[0045] The upper surface 43b, which will be described in detail later, is the surface against which the abutment surface 31a of the lever member 30 presses when the operating portion 31 is pressed down and the lever member 30 rotates. The locking member 40 is configured so that when the upper surface 43b is pressed by the abutment surface 31a, the locking member 40 rotates and the claw 43 disengages from the locking pin P1 (described in detail later).

[0046] The spring holder 45 is located below the support portion 41. As shown in FIG. 5 , a compression spring S1 is disposed in the spring holder 45. Specifically, the compression spring S1 is disposed in a compressed state between the spring holder 45 and the side surface of the housing 10 (see FIG. 5 ). The compression spring S1 is disposed, for example, in a recess formed as the spring holder 45. For example, the recess has a cylindrical space. This shape allows the compression spring S1, which is a coil spring, to be properly disposed within the recess. The compression spring S1 applies a biasing force to the locking member 40 in a direction that rotates the locking member 40 counterclockwise around the support pin P2. The compression spring S1 may be disposed not in a recess but in a protrusion (e.g., a shaft-shaped member) provided on a predetermined support member.

[0047] 7A, a pair of spring retaining portions 45 are provided. Specifically, the spring retaining portions 45 include one spring retaining portion 45 (first spring retaining portion) located on one end of the support pin P2 and a spring retaining portion 45 (second spring retaining portion) located on the other end. With this configuration in which the spring retaining portions 45 are formed on both ends of the support pin P2 and the compression springs S1 are disposed in the respective spring retaining portions 45, the biasing force of the springs is applied to the locking member 40 in a balanced manner, enabling the locking member 40 to operate smoothly.

[0048] <Operation of Locking Mechanism> (Locking Operation) Figure 8 is a diagram illustrating the locking operation of the locking mechanism 50. In the locking mechanism 50 of this embodiment, the locking mechanism 50 can be locked by closing the head cover 20. This will be described in detail below. As illustrated in Figure 8(a), a sloped portion 43d, which is a chamfered portion, may be formed between the upper surface 43b and the side surface 43c of the locking member 40. As an example, the sloped portion 43d is sloped at an angle of 45° with respect to the upper surface 43b.

[0049] 8A, when the head cover 20 is pushed down in the direction of the arrow, the lock pin P1 moves downward together with the head cover 20 toward the lock member 40. Then, the lock pin P1 abuts against the inclined surface 43a of the lock member 40.

[0050] 8(b), when the head cover 20 is further pressed down with the lock pin P1 in contact with the inclined surface 43a, the lock pin P1 slides on the inclined surface 43a. This causes the lock member 40 to rotate clockwise around the support pin P2. In other words, the lock member 40 rotates in a direction in which the claw 43 moves away from the lock pin P1.

[0051] As shown in Figure 8(c), when the head cover 20 is further pressed down, the claw 43 becomes caught on the lock pin P1. Then, as shown in Figure 8(d), the action of the compression spring S1 causes the lock member 40 to rotate counterclockwise around the support pin P2, and the claw 43 engages with the upper part of the lock pin P1.

[0052] The above steps lock the locking mechanism 50. According to the configuration of this embodiment, the locking mechanism 50 can be locked and the head cover 20 can be positioned in the closed position simply by pressing down the head cover 20. Therefore, no complicated operation is required for locking.

[0053] (First Unlocking Operation) Next, with reference to Figure 9, unlocking by pressing down the operating portion 31 will be described. Figure 9 is a diagram for explaining the first unlocking operation. When the operating portion 31 is pressed downward from the locked state shown in Figure 9(a) as indicated by the arrow, the lever member 30 attempts to rotate clockwise around the lock pin P1. As a result, the abutment surface 31a of the lever member 30 is pressed against the upper surface 43b of the locking member 40.

[0054] When the operating portion 31 is further pressed down from this state, the lever member 30 rotates clockwise around the lock pin P1 as shown in Figure 9(b). In response to this, the lock member 40 also rotates clockwise around the support pin P2. That is, the lock member 40 rotates in a direction in which the claw 43 moves away from the lock pin P1.

[0055] 9(c) to the state shown in FIG. 9(d), the locking member 40 rotates clockwise around the support pin P2, causing the claw 43 to disengage from the locking pin P1 and releasing the lock. Then, the head cover 20 springs upward due to the action of a biasing member (not shown) provided on the head cover 20, and the head cover 20 opens as shown in FIG. 1.

[0056] In this way, in the lock mechanism 50 of this embodiment, the lock of the lock mechanism 50 can be released by pressing down the operating portion 31 of the lever member 30 .

[0057] (Second Operation for Unlocking) Next, with reference to FIG. 10 , unlocking by pulling up the operating portion 31 will be described. FIG. 10 is a diagram for explaining the second operation for unlocking. In the locked state shown in FIG. 10( a), the extension portion 33 of the lever member 30 is located inside the locking member 40 (on the left side in the figure). The extension portion 33 is a member that forms the first abutment portion of the present invention, and extends downward from the operating portion 31 between the side surface of the housing 10 and the inner surface 47 of the locking member 40.

[0058] The operating portion 31 of the lever member 30 is pulled upward, for example, by an operator placing a finger on the underside of the operating portion 31 .

[0059] When an attempt is made to pull up the operating portion 31, the lever member 30 attempts to rotate counterclockwise around the lock pin P1, causing the extension portion 33 to rotate counterclockwise around the lock pin P1, and a portion of the extension portion 33 is pressed against the inner surface 47 of the lock member 40.

[0060] When the operating portion 31 is further pulled up from this state, as shown in Figure 10 (b), the lever member 30 rotates counterclockwise around the lock pin P1, and the extension portion 33 abuts against the inner surface 47 and presses against the same surface, thereby causing the lock member 40 to rotate clockwise around the support pin P2.

[0061] From this state, when the operating portion 31 is further pulled up and the locking member 40 moves clockwise about the support pin P2 from the state shown in Fig. 10(c) to the state shown in Fig. 10(d), the locking member 40 rotates to a position similar to the position of the locking member 40 shown in Fig. 9(d) described above. As a result, the claw 43 disengages from the locking pin P1, and the lock is released.

[0062] Then, in the same manner as above, the head cover 20 springs upward due to the action of a biasing member (not shown) provided on the head cover 20, and the head cover 20 opens.

[0063] As described above, in the locking mechanism 50 of this embodiment, the locking mechanism 50 can also be unlocked by pulling up the operating portion 31 of the lever member 30. In the configuration of this embodiment, as an example, the lever member 30 is configured so that the distance d1 is longer than the distance d2, as shown in FIG. 10( c). The distance d1 is the distance from the center of the locking pin P1 to the end of the operating portion 31. This distance d1 corresponds to the distance from the fulcrum to the point of force application. The distance d2 is the distance from the center of the locking pin P1 to the first abutment portion (the tip of the extension portion 33). This distance d2 corresponds to the distance from the fulcrum to the point of application. With this configuration, due to the principle of leverage, a force greater than the force applied to the operating portion 31 is applied to the locking member 40, thereby achieving the effect of unlocking with less force.

[0064] Although not an essential component of the present invention, the lever member 30 may have a retaining portion 34 formed on the upper portion of the extension portion 33, and this retaining portion 34 may be configured to hold down the head cover 20 from above as it attempts to spring up in the state shown in FIG. 10(d). In this example, the retaining portion 34 is a protrusion that abuts against the upper surface of the head cover 20 in the state shown in FIG. 10(d). When the retaining portion 34 is provided in this manner, the head cover 20 does not immediately open in the state shown in FIG. 10(d). When the operator slightly turns the lever member 30 counterclockwise around the lock pin P1, the retaining portion 34 disengages from the head cover 20, and the head cover 20 opens.

[0065] (Effects of the Thermal Printer and Locking Mechanism) As described above, the locking mechanism 50 of the thermal printer S100 of this embodiment can be unlocked by either pushing down or pulling up the operating portion 31 of the lever member 30. In particular, because the pushing down and pulling up operations are performed on a common operating portion 31 rather than on separate members, the structure is not complicated and operability for the operator is improved. The thermal printer S100 is incorporated into and used in a variety of devices, including kiosk terminals and POS terminals. Therefore, this configuration, which allows unlocking with multiple operations, allows the operator to unlock the locking mechanism 50 with an easy-to-operate action depending on the structure of the device in which it is incorporated.

[0066] <Modification 1> Fig. 11 is a diagram showing a modification of the locking mechanism. In Fig. 11, reference numerals in the 100s are used, and the numbers of the reference numerals correspond to the numbers of the reference numerals in the above-described embodiment.

[0067] As shown in FIG. 11 , the lever member 130 has an operating portion 131. As in the above embodiment, the operating portion 131 is a member that is the target of a push-down operation and a pull-up operation. The operating portion 131 has two extending portions 133. Each extending portion 133 is formed in a shape that pushes the inner surface 147 of the locking member 140 as the operating portion 131 rotates. The operating portion 131 may have any shape, and may be, for example, a slightly curved inclined surface as shown in FIG. 11 . A plurality of protrusions, such as ribbed or hemispherical protrusions, may be formed on the top surface of the operating portion 131 so that when the operator's finger touches the top surface, the operator can recognize that the location is the target of operation.

[0068] The locking member 140 has an inclined surface 143a, as in the above embodiment. In the example of FIG. 11 , a protrusion 143b' is formed on the top surface of the locking member 140. The protrusion 143b' has, for example, a substantially semicircular shape when viewed from the side. By forming it in this shape, the locking member 140 can be smoothly rotated while a contact surface (not shown) formed on the operating portion 131 presses against the protrusion 131b'.

[0069] <Modification 2> Figure 12 is a diagram schematically illustrating another example of use of the locking mechanism according to the present invention. Reference numerals in the 100s are used in Figure 12, and each reference numeral corresponds to the reference numerals in the above-described embodiments. The locking mechanism 150A has a lever member 130A and a locking member 140A. The structure and function of the locking mechanism 150A are similar to those of the above-described embodiment, and therefore detailed description thereof will be omitted.

[0070] In the above embodiment, the thermal head 25 is disposed in the head cover 20, and the platen roller 15 is disposed in the housing 10 (or vice versa). However, the locking mechanism 150A can be applied to various structures as long as the second member 120 is configured to rotate relative to the first member 110. The first member 110 is, for example, a housing, but is not limited to this and may be any member. The second member 120 is, for example, a cover or lid, but is not limited to this and may be any member. The parts, devices, etc. housed in the first member 110 and the second member 120 are also not limited to specific ones.

[0071] Thus, the locking mechanism 150A is a locking mechanism that locks the second member 120 to the first member 110, and includes a lever member 130A that is rotatably supported on the second member 120 and has an operating portion that is operated by an operator, and a locking member 140A that maintains the second member 120 in a closed position.

[0072] <Other Configuration Examples> Fig. 13 is a schematic diagram showing another configuration example of the example in Fig. 12. The locking mechanism 150A may have the configuration shown in Fig. 13. The locking mechanism 150A is a mechanism that fixes the second member 120 to the first member 110. The locking mechanism 150A has a lever member 130A and a locking member 140A.

[0073] Lever member 130A is a member formed with operating portion 131A that is operated by an operator. Lever member 130A is, as an example, rotatably supported on second member 120 via first axis P1a. Lever member 130A may also be supported on a member separate from second member 120.

[0074] The locking member 140A is a member formed with a pawl (not shown) that engages with the first shaft P1a. In this example, the locking member 140A is supported by the first member 110 via the second shaft P2a. The pawl of the locking member 140A engages with the first shaft P1a, thereby maintaining the second member 120 in the locked position.

[0075] As in the above-described embodiment, the lever member 130A and the locking member 140A are configured such that (i) from a locked state in which the claw of the locking member 140A is engaged with the first axis P1a, when the operating portion 131A of the lever member 130A moves in a first direction (e.g., downward in FIG. 13 ), the locking member 140A rotates in a direction in which the claw moves away from the first axis P1a, and the claw disengages from the first axis P1a, thereby releasing the lock. Furthermore, the lever member 130A and the locking member 140A are configured such that (ii) when the operating portion 131A of the lever member 130A moves in a second direction (e.g., upward in FIG. 13 ) opposite to the first direction, a part of the lever member 130A presses the locking member 140A, thereby rotating the locking member 140A in a direction in which the claw moves away from the first axis P1a, and the claw disengages from the first axis P1a, thereby releasing the lock.

[0076] The present invention has been described above using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by functionally or physically distributing or integrating in any unit. Furthermore, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effects of the new embodiments resulting from the combination also have the effects of the original embodiments.

[0077] 10 Housing 11 Connecting pin 15 Platen roller 18 Base member 20 Head cover 25 Thermal head 30 Lever member 31 Operating portion 31a Contact surface 33 Extension portion 33a Protrusion 33h Through hole 34 Pressing portion 40 Locking member 41 Support portion 41h Through hole 43 Claw 43a Inclined surface 43b Upper surface 45 Spring holding portion 47 Inner surface 50 Locking mechanism 110 First member 120 Second member 130 Lever member 130A Lever member 131 Operating portion 131A Operating portion 131b' Protrusion 133 Extension portion 140 Locking member 140A Locking member 143a Inclined surface 143b' Protrusion 147 Inner surface 150A Lock mechanism P1 Lock pin P1a First shaft P2 Support pin P2a Second shaft S Paper S1 Compression spring S2 Spring S100 Thermal printer

Claims

a housing that holds the platen roller so that the platen roller can rotate; a cover that holds the thermal head and is connected to the housing so as to be openable and closable with one side in the width direction of the paper as a fulcrum, the cover being movable between a closed position where the thermal head abuts against the platen roller and an open position where the thermal head is separated from the platen roller; and a locking mechanism that locks the cover to the housing, wherein the locking mechanism comprises: a lever member that is rotatably supported by the cover and has an operating portion that is operated by an operator; and a locking member that is rotatably supported by the housing and has a claw that engages with a locking pin of the cover, the claw engaging with the locking pin to maintain the cover in the closed position, wherein the lever member and the locking member are A thermal printer configured such that when the operating portion is pushed down, the locking member rotates in a direction such that the claw moves away from the lock pin, and the lock is released when the claw disengages from the lock pin, and when the operating portion of the lever member is pulled up, a first abutment portion that is part of the lever member presses the locking member, thereby rotating the locking member in a direction such that the claw moves away from the lock pin, and the lock is released when the claw disengages from the lock pin.

2. The thermal printer according to claim 1, further comprising a biasing member that applies a biasing force to said cover in a direction in which said cover opens, and that pops up said cover when said lock is released.

3. A thermal printer as described in claim 1 or 2, wherein the portion of the lever member is located between the locking member and the cover in the closed position, and the lever member and the locking member are configured such that, when the operating portion is pulled up and the lever member rotates, the first abutment portion pushes the locking member in a direction in which the claw moves away from the locking pin, thereby causing the claw to disengage from the locking pin.

4. The thermal printer according to claim 3, wherein the lever member is configured to rotate around the lock pin, and the distance from the center of the lock pin to the end of the operating portion is longer than the distance from the center of the lock pin to the first contact portion.

5. A thermal printer as described in claim 1 or 2, wherein the claws include a first claw that engages with a first position in the longitudinal direction of the lock pin, and a second claw that engages with a second position in the longitudinal direction of the lock pin, and the first abutment portion is formed at the tip of an extension portion that extends at a position between the first claw and the second claw.

6. A thermal printer as described in claim 1 or 2, wherein the lever member has a second abutment portion that abuts against the locking member when the operating portion is pressed down, and the lever member and the locking member are configured such that, when the operating portion is pressed down and the lever member rotates, the locking member is pushed by the second abutment portion, thereby rotating the locking member and disengaging the claw from the locking pin.

7. A thermal printer as described in claim 1 or 2, wherein the locking pin extends in the transport direction of the paper, and the locking member has an inclined surface against which the locking pin, which moves toward the locking member when the cover is pushed down, presses, and when the cover is pushed down with the locking pin in contact with the inclined surface, the locking pin slides along the inclined surface, thereby rotating the locking member in a direction in which the claw moves away from the locking pin, and when the cover is pushed down further, the claw engages with the locking pin.

8. A thermal printer as described in claim 1 or 2, wherein the locking member has a support portion supported by a support pin provided on the side of the housing, the claw provided above the support portion, and a spring holding portion provided below the support portion, and a compression spring is disposed between the spring holding portion and the side of the housing, and the compression spring urges the locking member in a direction in which the claw is pressed against the locking pin.

9. A thermal printer as described in claim 8, wherein the support pin extends in a direction parallel to the paper transport direction, and the spring retaining portion is provided with a first spring retaining portion located on one end side of the support pin, and a second spring retaining portion located on the other end side of the support pin.

10. The thermal printer according to claim 8, wherein the lock pin and the support pin are arranged parallel to each other, and when the cover is in the closed position, the claw engages with an upper part of the lock pin.

11. A thermal printer according to claim 1 or 2, wherein the operation unit is located at one end of the cover along the periphery of the top surface of the cover.

12. In a printing device comprising a housing that holds one of a thermal head and a platen roller that print on paper, and a cover that holds the other of the thermal head and the platen roller and is connected to the housing so as to be able to open and close with one side in the width direction of the paper as a fulcrum, a locking mechanism that locks the cover to the housing comprises: a lever member that is rotatably supported on the cover and has an operating section that is operated by an operator; and a locking member that is rotatably supported on the housing and has a claw that engages with a locking pin of the cover, the claw engaging with the locking pin to maintain the cover in a closed position, wherein the lever member and the locking member are A locking mechanism configured such that when the operating portion is pushed down, the locking member rotates in a direction such that the claw moves away from the lock pin, and the lock is released when the claw disengages from the lock pin, and when the operating portion of the lever member is pulled up, a part of the lever member presses the locking member, thereby rotating the locking member in a direction such that the claw moves away from the lock pin, and the lock is released when the claw disengages from the lock pin.

13. A locking mechanism for locking a second member to a first member, comprising: a lever member rotatably supported on the second member and formed with an operating part operated by an operator; and a locking member rotatably supported on the first member and formed with a pawl that engages with a first axis of the second member, the pawl engaging with the first axis to maintain the second member in a locked position, wherein the lever member and the locking member are configured such that: (i) from a locked state in which the pawl is engaged with the first axis, the operating part of the lever member moves in a first direction, causing the locking member to rotate in a direction in which the pawl moves away from the first axis, and the pawl disengages from the first axis, thereby releasing the lock; and (ii) the operating part of the lever member moves in a second direction opposite to the first direction, causing a part of the lever member to push the locking member, thereby causing the locking member to rotate in a direction in which the pawl moves away from the first axis, and the pawl disengages from the first axis, thereby releasing the lock.

Images