JP2810908B2 - Support device for recording head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head support device in a printer for printing on thermal paper using a thermal head, for example.

[0002]

2. Description of the Related Art As a first prior art, a recording head resiliently contacted with a platen by a spring, a release lever swingably provided on a side of a head supporting plate for supporting the recording head, and A coupling member that is displaced in conjunction with the swing of the release lever and a release cam that is pivotally driven in accordance with the displacement of the coupling member are provided. In use, there is a recording apparatus capable of keeping the recording head separated from the platen in order to prevent deformation of the platen (Japanese Utility Model Application Laid-Open No. 21397).
No. 52).

[0003] As a second prior art, a front cover side in which a recording head is provided inside a case main body and roll holders for storing and holding rolls of a platen and recording paper are respectively provided on the front surface of the case main body so as to be freely opened and closed. Is provided with a recording device.

[0004]

In a configuration in which the release lever is manually driven to swing and the recording head is pulled away from the platen as in the first prior art described above, the recording head and the platen come into elastic contact with each other. The recording paper cannot be fed in a state where the recording head is separated from the platen, that is, in a recording standby state.

In a configuration in which a roll holder and a platen are provided on the front cover side as in the second prior art, when exchanging the roll of recording paper, the front cover is opened and the roll of recording paper is removed. It is only necessary to close the front cover after setting the tip so that it rests on the platen, and while loading the recording paper is easy,
For example, when opening the front cover, the recording head on the case body side is manually or electrically separated from the platen so that the recording head does not come into contact with the platen during the opening / closing operation so that the platen is not damaged by friction. Need to be If the configuration is made to satisfy this need, many components are required, the configuration becomes complicated, and the cost becomes high. Also, in the second prior art, as in the first prior art, the recording paper cannot be fed in a state where the recording head is separated from the platen, that is, in a recording standby state.

SUMMARY OF THE INVENTION It is a first object of the present invention to realize a simple structure that allows a recording head to be loaded from a platen so that recording paper can be loaded without damaging the platen.

A second object of the present invention is to press a recording head with a small force (preliminary pressing) on a platen in a recording standby state, so that the recording paper can be fed even in the recording standby state. An object of the present invention is to provide a recording head support device.

[0008]

In order to solve the above-mentioned problems, a recording head supporting apparatus according to the present invention is provided such that a head supporting plate is swingably engaged with a supporting shaft fixed to a supporting frame with a gap. A recording head is provided on the head support plate, an opening / closing member is swingably connected to the support frame, and a platen is attached to the opening / closing member so as to face the recording head when the opening / closing member is in the closed position. Is provided rotatably, and when the opening and closing member is in the closed position, the shaft of the platen is
Or it is provided on the opening and closing member to support the shaft rotatably
A regulating plate that can contact a certain bearing is integrated with the head support plate
An auxiliary lever engaged with a part of the head support plate is swingably provided on the support frame, and the auxiliary lever can abut when the opening / closing member is in the closed position. Is provided on the opening and closing member, and when the opening and closing member is in the closed position, the recording head is resiliently contacted with the platen via the head support plate and the head support plate is biased toward the platen shaft or bearing. When the opening / closing member is at the open position while urging the spring force, an urging spring for urging the spring force in a direction separating the recording head from the platen via the head support plate is provided between the support frame, the head support plate, and the support frame. It is provided between the lever.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An overall configuration will be described with reference to FIGS.
The support frame 1 formed of a metal plate is bent in a U-shape, and a right plate 1a, a left plate 1b, and a bottom plate 1c are integrally formed. In order to keep the right side plate 1a and the left side plate 1b parallel at a predetermined interval, the fixed plate 2 is made up of both side plates 1a, 1b.
It is fixed to the rear upper part. At the lower corner of the front end of the support frame 1, a shaft 3 having a circular cross section is provided transversely to the left and right.

An opening / closing member 4 covering the front surface of the support frame 1 and having a substantially L-shaped side surface is rotatably supported on the shaft 3. A spring 30 (see FIG. 3) is hung between the support frame 1 and the opening / closing member 4 via the shaft 3, and the opening / closing member 4 is urged in the opening direction by the spring force of the spring 30. Have been.

On the inner surface of the opening / closing member 4, a recording paper holder 5 (FIG. 5) for storing and holding a recording paper P wound in a roll shape.
Reference). A locking piece 4c formed at the rear end of the opening / closing member 4 is locked to the lower surface of the rear end of the recording paper holder 5, and the recording paper holder 5 is fixedly held by the opening / closing member 4. . A pair of bearings 6, 6 are provided at the upper end of the opening / closing member 4.
The platen shaft 7a is rotatably supported via the pair of bearings 6 and 6. This platen shaft 7
A is provided with a cylindrical platen 7 formed of silicon rubber. In the vicinity of the bearings 6, 6, regulating portions 4a, 4a to be described later are formed by bending the opening / closing member 4. As shown in FIGS. 5 and 6, as a means for holding the open / close member 4 in a closed state, an engagement projection 18 is formed on the rear end side of the recording paper holder 5 so as to protrude. A push latch 19 that engages with and catches the projection 18 is provided inclined forward.

A support shaft 8 having a circular cross section is fixedly provided substantially across the upper center of both side plates 1a and 1b of the support frame 1 (see FIG. 2). This support shaft 8 has a head support plate 9
Are engaged by the following structure. As shown in FIG. 6, tongues 9d and 9e are bent at both sides of the support portion 9c at the rear end of the head support plate 9, and a U-shaped portion formed by both tongues 9d and 9e. The hole 9f is engaged with the lower portion of the support shaft 8 with a predetermined gap d. Therefore, the support portion 9c of the head support plate 9 is swingably engaged with the fixed support shaft 8 and movably engages with the fixed support shaft 8 within a range allowed by the gap d.

On the lower surface of the front end of the head support plate 9, a heat-sensitive recording head (thermal head) 1 in which heating elements (not shown) for one line are arranged at a fine pitch in a horizontal line.
0 is provided.

Next, the relative positional accuracy between the recording head 10 and the platen 7 is increased and maintained, and a slight friction is provided between the recording head 10 and the platen 7 during recording standby. A means for holding a state in which the platen 7 is slightly pressurized so as not to be deformed (preliminary pressurized state) will be described with reference to FIGS. Although FIG. 3 shows the right side of the present apparatus, the same configuration as FIG. 3 is provided on the left side of the present apparatus. As shown in FIGS. 1 and 3, on both sides of the head support plate 9, regulating plates 9a, 9a are formed by bending downward.
The restricting plates 9a, 9a are formed with engaging pieces 9b, 9b which bend further to the side. The engagement piece 9b is engaged with an upper side of an engagement portion 12a of the auxiliary lever 12, which will be described later. When the opening / closing member 4 is in the closed position (the state shown in FIG. 3), the front end sides of the regulating plates 9a, 9a can be brought into contact with the outer peripheral surfaces of a pair of bearings 6, 6 provided on the opening / closing member 4. It is.

As shown in FIGS. 1 and 3, pins 11 are provided on both side plates 1a and 1b of the support frame 1, and auxiliary levers 12 and 12 are swingable on the pins 11 and 11 respectively. It is pivotally supported. The auxiliary lever 12 has the engaging portion 1
2a is provided, and an engaging piece 9b of a regulating plate 9a formed on the head support plate 9 is engaged with the upper side of the engaging portion 12a. Projection piece 12 bent and formed on auxiliary lever 12
The center of the biasing spring (coil spring) 13 is provided at b. One end 13 a of the biasing spring 13 is hung on a protruding end of the support shaft 8 fixed to the support frame 1. The other end 13b of the biasing spring 13 is hung on the engaging piece 9b of the regulating plate 9a. Therefore, the spring force of the urging spring 13, that is, the spring force acts on each member in the direction in which the one end 13a and the other end 13b of the urging spring 13 expands, the one end 13a of the urging spring 13 is urged. At the same time as the lever 12 is urged to swing clockwise around the pin 11, the other end 13b of the urging spring 13 moves the engagement piece 9b obliquely downward and forward (obliquely downward left in FIG. 3). Energize to do.

The front edge of the engaging portion 12a of the auxiliary lever 12 comes into contact with the restricting portion 4a which is bent and formed on the opening / closing member 4 when the opening / closing member 4 is closed (the state shown in FIG. 3). In this state (the state shown in FIG. 3), clockwise swing of the auxiliary lever 12 around the pin 11 is restricted.

With this structure, when the opening / closing member 4 is in the closed position (the state shown in FIG. 3), the regulating force of the head supporting plate 9 is generated by the spring force of the other end 13b of the biasing spring 13. 9a is urged obliquely downward and forward (obliquely downward left in FIG. 3), so that the regulating plate 9a comes into contact with the bearing 6,
In addition, the recording head 10 is slightly pressurized on the platen 7 so as to be in a pre-pressurized state in which light friction is provided between the platen 7 and the platen 7. As a result, the recording head 10 slides forward together with the head support plate 9 to correctly oppose the platen 7, the relative position between the recording head 10 and the platen 7 is maintained with high accuracy, and the recording head 10 And is preliminarily pressed by the urging spring 13. The pre-pressing force is so small that the platen 7 itself is not deformed and is a necessary and sufficient force to feed the recording paper P. When the pre-pressing force is set to, for example, 200 gf / the entire platen length (108 mm), the recording head 10 and platen 7
And a slight friction between them, so that paper can be fed even during printing standby.

The one end 13a of the biasing spring 13 is to be hooked directly to the support frame 1 or to a member fixedly connected thereto, and it is indispensable to hook it to the support shaft 8. It does not do.

The position of the recording head 10 with respect to the platen 7 is determined by bringing the front end of the regulating plate 9a of the head support plate 9 into contact with the outer peripheral surface of the bearing 6 of the platen shaft 7a. The front end side of the regulating plate 9a of the support plate 9 may directly contact the outer peripheral surface of the platen shaft 7a.

Next, means for separating the recording head 10 from the platen 7 when the opening / closing member 4 is opened will be described. As shown in FIG. 4, when the opening / closing member 4 starts to be opened, the contact between the front end edge of the auxiliary lever 12 and the restricting portion 4 a formed by bending the opening / closing member 4 is released. For this reason, the auxiliary lever 1
2 rotates clockwise around the pin 11 under the force of the urging spring 13, the engaging portion 12 a lifts the regulating plate 9 a upward, and the recording head 10 together with the head support plate 9 moves from the platen 7. Separate.

With this configuration, when the opening / closing member 4 is opened, the recording head 10 is separated from the platen 7, so that both the platen 7 and the recording head 10 are not damaged.

Next, means for strongly pressing (mainly pressing) the recording head 10 against the platen 7 for a recording operation will be described. As shown in FIGS. 2 and 6, a pair of head pressure plates 14 and 14 are pivotally supported on a support shaft 8. One end portions 14a, 14a of the head pressure plates 14, 14 extend forward, and their lower surfaces 14b, 14b
Is opposed to the upper surface. Here, the head pressure plates 14, 1
As shown in FIG. 2, each of the lower surfaces 14b, 14b of the head support plate 9 is symmetrical with respect to a line (not shown) that divides the platen 7 into two orthogonal to the direction of the axis 7a.
Is opposed to the upper surface.

As shown in FIG. 6, the head pressure plates 14, 1
Each of the other end portions 14c, 14c of 4 is a surface that extends rearward and receives a force for releasing the pressing force, that is, a surface that engages with a cam 17 described later. Also, the head pressure plates 14, 1
4, pressurizing springs 15, 15 are stretched between the rear ends 14 d, 14 d and the fixed plate 2.
5, the head pressure plates 14 and 14 swing counterclockwise about the support shaft 8 as the swing center, and come into contact with the upper surface of the head support plate 9 to apply the recording head 10 to the platen 7. It is repelled in the direction to press.

With this configuration, as shown in FIGS. 2 and 7, the lower surfaces 14b, 14b of the head pressing plates 14, 14 receive the spring force of the pressing springs 15, 15, and The upper surface of the head support plate 9 is pressurized at a position symmetrical with respect to a line (not shown) which is orthogonal to the direction of the axis 7a and divided into two. As a result, there is an error in the accuracy of the individual components and the accuracy of assembly, and even if these accumulate and the platen 7 is inclined with respect to the support frame 1, the support portion 9c of the head support plate 9 can Since the head support plate 9 follows the inclination of the platen 7 and pressurizes the recording head 10 because it is swingably engaged with the fixed support shaft 8 and movably engages within a range allowed by the gap d. The platen 7 can be evenly pressed (mainly pressed) over its entire length. At this time, the pressure applied to the platen 7 by the recording head 10 is set to, for example, 2 kgf / full length of the platen (108 mm). This pressurization causes the apparatus to enter a recordable state for the first time.

Next, a description will be given of a means for releasing the main pressure on the platen 7 of the recording head 10 described above. As shown in FIG. 2 and FIG.
A cam shaft 16 having a circular cross section is rotatably supported across the rear part of b, and a main pressure switching cam 17 is fixed to the cam shaft 16. The main pressure switching cam 17 is opposed to the other end 14c of the head pressure plate 14, and its cam surface has a shape that is continuous with a smooth surface from a large-diameter peak 17a to a small-diameter valley 17b. (See FIG. 6). In addition, as shown in FIG.
1 in the normal state (recording standby state) at the time of non-recording operation.
As shown in FIG.
The lower surface 1 of the head pressure plate 14 is brought into contact with the other end 14c of the head.
4b is separated from the upper surface of the head support plate 9, and the recording head 1
The state where the main pressurization for the platen 7 of 0 is released is maintained. Note that a lock switching cam 22 described later is fixed to the cam shaft 16.

Next, during the recording operation, that is, the recording head 1
A lock means for locking the opening / closing member 4 so as not to open when 0 is fully pressurizing the platen 7 will be described. As shown in FIGS. 6 and 7, the opening / closing member 4 is closed during the recording operation. At this time, the engaging projection 18 is captured by the push latch 19. When the closed opening / closing member 4 is pushed from the front (left side in FIG. 6), the engaging projection 18 is released from the push latch 19, and the opening / closing member 4 is supported by the spring force of the spring 30 (see FIG. 3). 1 (state shown in FIG. 5). During the recording operation in which the recording head 10 is performing recording, a pin 20 provided on the right side plate 1a of the support frame 1 is locked as shown in FIGS. An L-shaped lock member 21 is provided to be swingable.

An engaging claw 21a is provided at one end of the lock member 21.
Is provided. This engaging claw 21a is shown in FIGS.
And a locking piece 4b formed at the rear end of the opening / closing member 4 shown in FIG. The other end 21 b of the lock member 21 is engaged with a cam surface of a lock switching cam 22 fixed to the cam shaft 16. The lock member 21 includes a lock spring 2.
3 is supported via a pin 20, and the spring force of the lock spring 23 urges the lock member 21 clockwise around the pin 20 to engage the engaging claw 21a with the locking piece 4b. And the other end 21b is locked by the lock switching cam 2
It is urged in the direction to come into contact with 2. Lock switching cam 2
The cam surface of No. 2 includes a large-diameter peak portion 22a and a small-diameter valley portion 22b
It has a shape that is continuous on a smooth surface (see FIG. 6).

In the state shown in FIG. 6, that is, when the head pressing plate 14 does not fully press the head support plate 9 (preliminary pressing state), the other end 21b of the lock member 21 is fixed to the large diameter of the lock switching cam 22. Since the lock member 21 is engaged with the ridge 22a, the lock member 21 maintains a state in which the engagement claw 21a is separated from the locking piece 4b of the opening / closing member 4 against the spring force of the lock spring 23. . In this state, by pushing the opening / closing member 4 from the front (left side in FIG. 6), the engaging projection 18 is released from the push latch 19, and the opening / closing member 4 is opened by the spring force of the spring 30 (see FIG. 3). (The state of FIG. 5).

In the state shown in FIG. 7, that is, in a state where the head pressing plate 14 fully presses the head supporting plate 9 and a recording operation is being performed, the other end 21 b of the lock member 21 is positioned at the small diameter valley 22 b of the lock switching cam 22. The locking spring 2 is engaged.
3, the lock member 21 causes the engagement claw 2
1a is held in a state of being locked to the locking piece 4b of the opening / closing member 4. In this state, the opening / closing member 4 is moved forward (left side in FIG. 6).
Even if it is pushed in, the opening and closing member 4 cannot be opened because the locking piece 4b is prevented from being displaced. That is, the opening and closing of the opening and closing member 4 is locked by the lock member 21.

Next, the mutual positional relationship between the lock switching cam 22 and the pressure switching cam 17 will be described. FIG.
As shown in FIG.
Is engaged with the other end 14c of the head pressing plate 14 and the recording head 10 is not fully pressed to the platen 7 (preliminary pressing state). Are engaged with the other end 21b of the lock member 21. At this time, the opening / closing member 4 can be opened.

As shown in FIG. 7, the small diameter valley 17b of the pressure switching cam 17 faces the other end 14c of the head pressure plate 14, and the recording head 10 is fully pressed to the platen 7. At the time, the small diameter valley 2 of the lock switching cam 22
2b is engaged with the other end 21b of the lock member 21. At this time, the opening / closing member 4 cannot be opened.

Next, a configuration for driving the cam shaft 16 to rotate will be described. As shown in FIGS. 2 and 8, a gear 24 is fixed to the camshaft 16. A forward / reverse rotation motor M1 is fixedly provided on the bottom plate 1c. The rotation from the motor M1 is transmitted to the gear 24 via the transmission wheel train 25, whereby the cam shaft 16 is driven to rotate forward and reverse.

Although the pressure switching cam 17 and the lock switching cam 22 are provided on the same cam shaft 16, they are separately formed as a first cam shaft and a second cam shaft, respectively. The shafts may be configured to be separately driven as needed by different drive sources, or may be configured to be rotationally driven by the same drive source via separate transmission mechanisms.

Next, a configuration for driving the platen 7 to rotate will be described. As shown in FIG. 2, a motor M2 is fixedly provided on the left side plate 1b. The rotation from the motor M2 is transmitted to the platen shaft 7a via the transmission wheel train 26 and the belt 27, and the platen 7 is driven to rotate.

Next, the drive timing of the motors M1 and M2 will be described. By pressing a print button (not shown) connected to the apparatus, first, the motor M1 is pressed.
Is started, and the camshaft 1 is transmitted via the transmission train 25 (see FIG. 8).
6 is rotated counterclockwise from the state of FIG. 6, and when the state of FIG. 7 is reached, the motor M1 stops. Motor M
The stop of 1 is controlled by an output from a photosensor (not shown) that detects a rotation angle of the rotation plate (encoder plate) (not shown) provided on the camshaft 16 (not shown). When the motor M1 stops, the motor M2 starts, and the shaft 7a of the platen 7 is driven to rotate in the paper feeding direction via the transmission train 26 (see FIG. 2), so that a recording operation for one screen is performed on the recording paper P. You. When the recording operation for one screen is completed, the motor M2 stops and the platen 7
Rotation stops. And immediately the motor M1 starts,
The camshaft 16 is now driven to rotate clockwise from the state shown in FIG. 7 via the transmission wheel train 25, and when the state shown in FIG. 6 is reached, the motor M1 stops.

Next, the loading of the roll-shaped recording paper P into the apparatus will be described. 1 and 3, when the opening / closing member 4 is pushed in from the front (left side in FIG. 3), the engaging projection 18 shown in FIG.
The opening / closing member 4 is opened by the spring force of FIG.
The state shown in FIG. When the opening / closing member 4 is in the fully opened state (the state shown in FIG. 5), the roll-shaped recording paper P can be stored in the recording paper holder 5. At this time, the leading edge of the recording paper P is slightly pulled out, and the recording paper P is kept on the platen 7.

When the opening / closing member 4 is closed from the state shown in FIG. 5, the recording head 10 is at a position where it correctly faces the platen 7 as described with reference to FIG. 3, and the leading end of the recording paper during this closing operation is as shown in FIG. Then, it is naturally located in a state where it is drawn outside through the space between the recording head 10 and the platen 7. In the state of FIG. 6 (preliminary pressurized state), the engaging projection 18 and the push latch 19 are engaged, but the engaging claw 21 a of the lock member 21 is locked by the locking piece 4 b of the opening / closing member 4. And one end 14a of the head pressure plate 14
The lower surface 14b is not in a state capable of recording on the recording paper P but in a recording standby state because the recording head 10 is not fully pressed against the platen 7.

In the state shown in FIG. 6 (preliminary pressurized state), the ridge 17a of the pressure switching cam 17 presses the other end 14d of the head press plate 14 so that one end 14a is moved from the head support plate 9. is seperated. Further, since the crest 22a of the lock switching cam 22 raises the other end 21b of the lock member 21, the engaging claw 21a of the lock member 21
Is not engaged with the locking piece 4b. Therefore, the motor M1
Is driven to rotate the cam shaft 16 in the counterclockwise direction, both the pressure switching cam 17 and the lock switching cam 22 rotate counterclockwise.

As shown in FIG. 7, the peaks 17a of the pressure switching cam 17 are connected to the other end portions 14 of the head pressure plates 14, 14.
When the pressing of c, 14c is released, the pressing springs 15, 15 are released.
, The two head pressure plates 14, 14 swing counterclockwise about the support shaft 8, and the two head pressure plates 14, 14.
The lower surfaces 14b, 14b of the first ends 14a, 14a of the first and second portions 14a, 14a strongly press (actually press) the recording head 10 in a direction in which the recording head 10 elastically contacts the platen 7 in the longitudinal direction. The pressing force at this time is set to, for example, 2 kgf / platen width (108 mm). The recording is possible only for the first time by this main pressure.

Further, as described above, when the cam shaft 16 rotates counterclockwise, the peak 22a of the lock switching cam 22 separates from the other end 21b of the lock member 21, and
The lock member 21 swings clockwise around the pin 20 by the spring force of the lock spring 23. Therefore, the engagement claws 21
Since a is locked to the locking piece 4b, it cannot be pushed backward to open the opening / closing member 4 anymore, and the opening / closing member 4 is not opened. Therefore, during the recording operation, the opening / closing member 4 does not unexpectedly open, and stable recording can be performed.

At the end of the recording operation, the motor M1 is driven again to rotate the pressure switching cam 17 and the lock switching cam 22, so that the peaks 17a, 22a are engaged with the other ends 14c, 21b. 6, the recording paper P can be exchanged.

In the state shown in FIG. 6, since the recording head 10 is in a pre-pressurized state in which the platen 7 is slightly pressurized by the urging spring 13, there is friction between the recording head 10 and the platen 7. And paper can be fed.

In the state shown in FIG. 6, the head pressure plate 1
4 and 14 do not fully press the head support plate 9 and are in a pre-pressurized state where the platen 7 itself is not deformed.
The platen 7 can be prevented from being deformed by the pressurization of the recording head 10 against the platen 7 for a long time.

[0044]

As described above, according to the present invention,
When loading the recording paper, simply press the opening and closing member from the front to open the recording head and the platen that are in contact with each other, and automatically separate the recording head from the platen,
The recording paper can be loaded without damaging the platen with a simple configuration. Also, even in the recording standby state, the recording head is slightly pressed against the platen, so that a light friction is given between the two, so that the recording paper can be fed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a right side view of the same.

FIG. 4 is a right side view showing an initial state in which the opening / closing member is opened.

FIG. 5 is a right side view showing a state where the opening / closing member is fully opened.

FIG. 6 is a cross-sectional view showing a state where the recording head is not fully pressed.

FIG. 7 is a cross-sectional view illustrating a state in which the recording head is fully pressurized.

FIG. 8 is a sectional view showing a configuration for driving a cam shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support frame 4 Opening / closing member 4a Restrictor 6 Bearing 7 Platen 7a Platen shaft 8 Support shaft 9 Head support plate 10 Recording head 12 Auxiliary lever 13 Urging spring

Claims (1)

(57) [Claims] A head support plate swingably engaged with a support shaft fixed to the support frame with a gap; a recording head provided on the head support plate; An opening / closing member that is freely connected; a platen rotatably provided on the opening / closing member and facing the recording head when the opening / closing member is in a closed position; and a platen provided integrally with the head support plate. , The opening and closing member is
When in the closed position, rotate the platen shaft or the shaft
To the bearing provided on the opening / closing member to rotatably support
A regulating plate that can be brought into contact with, an auxiliary lever that is swingably provided on the support frame and is engaged with a part of the head support plate; A regulating portion to which the auxiliary lever can contact when in the closed position, provided between the support frame, the head support plate, and the auxiliary lever, and when the opening and closing member is in the closed position. A biasing force is applied in a direction in which the recording head is elastically contacted with the platen via the head support plate and a direction in which the regulating plate is biased toward the shaft of the platen or the bearing. And a biasing spring for biasing the recording head through the head support plate in a direction away from the platen when in the open position.