JPH0976616A - Stamp apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a stamp apparatus stamping a free design, capable of rapidly setting a printing gap corresponding to the thickness of printed matter by a simple structure and capable of realizing the capping of an ink jet head by a simple structure. SOLUTION: A stamp apparatus is equipped with the guide shaft 3 of which both ends are fixed to the side walls of a frame, the printing head 1 mounted on the carrier running along the guide shaft, the paper stand 9 arranged under the printing head in a freely liftable manner, the spring energizing the paper stand upwardly, the stopper coming into contact with the upper surface of the paper stand 9 in a state leaving a predetermined head gap between the leading end of the printing head 1 and the paper stand and a push-down mechanism pushing the paper stand downwardly. By bringing printed matter into contact with the stopper by the energizing force of the spring, a proper printing gap is rapidly set. The capping mechanism of the printing head advancing and retreating in connection with a reverse direction by utilizing the lift operation of the paper stand 9 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stamping device used for postmarking a postal matter, and the like, using an ink jet head or a thermal transfer type print head.
The present invention relates to a device capable of stamping a freely designed stamp.

[0002]

2. Description of the Related Art A conventional stamping device for mail or the like has a structure of pressing a certain stamp by using a rubber stamp or a stamp impregnated with ink.

On the other hand, conventionally, a printer using an ink jet head or a wire dot head has been widely used as a printer for printing an address or the like on an envelope. These printers require that the distance between the tip of the print head and the printing surface (print gap) be set to a desired accurate value in order to obtain clear print, and the print head is adjusted to the thickness of the paper. It is necessary to finely adjust the distance between the tip of the platen and the platen. FIG. 5 shows an example of a print gap setting mechanism in a conventional printer of this type.
The carrier 2 on which the print head 1 is mounted is guided by a guide shaft 3 extending long in the direction perpendicular to the plane of the drawing and a guide bar 4 arranged in parallel with the guide shaft 3. Guide shaft 3
The shaft end 26 is rotatably supported by the frame at its shaft end 26, but the shaft end 26 is provided displaced from the center of the guide shaft 3. A drive motor 28 is connected to a gear provided at this shaft end via a gear train 27. When the drive motor 28 is rotated, the guide shaft 3 rotates around its shaft end 26, and the guide shaft 3 itself serves as an eccentric cam to move the carrier 2 up and down. This vertical movement is detected by the gap sensor 29, and the motor 28 is stopped when the distance between the print head 1 and the paper 25 reaches a desired distance. In the structure shown in the figure, the guide bar 4 is sandwiched by two rollers 31, 31 axially attached to the carrier 2, and the guide bar 4 defines the position of the carrier 2 around the guide shaft 3.

When an ink jet head is used as the print head 1, in order to prevent the ink from evaporating and solidifying at the tip of the head when the printing operation is not performed,
Capping is done. Conventionally, this capping is performed by utilizing the movement operation of the carrier along the guide shaft 3.

FIG. 6 shows an example of such a structure. The cap 14 is movable in the left-right direction in the drawing along the guide shaft 3, and the cap 14 is moved upward at the home position of the print head. A slide plate 32 for guiding is provided, and a stopper 33 is fixed to the cap 14. When the print head 1 moves to the home position, the print head 1 (or its carrier) contacts the stopper 33 and moves the cap 14 below the home position. Along with this movement, the cap is guided by the slide plate 32 to move upward and is attached to the print head 1 at the home position.

[0006]

A stamp device using a stamp such as a rubber stamp cannot change the design of the stamp to be stamped. Many characters, such as dates, can be exchanged by rotating or replacing the surface, but the overall design is constant, and when changing this, the entire format must be replaced.

[0007] Postmarks of postal items have not been given much design consideration in the past, but for example, postal items associated with a particular event must be postmarked with a design reminiscent of the event. Obviously, this is more preferable.

In order to enable stamps of various designs to be stamped, it is conceivable to use an ink jet head or a thermal transfer type print head instead of a rubber stamp or the like to stamp the postmark. In this case, a mechanism for adjusting the head gap and capping the inkjet head when not in use is required as in the case of conventional printers, etc., but postmarking of postal items is performed after the contents are enclosed in an envelope. Therefore, the thickness of the printing paper is mixed in various ways, and the conventional head gap adjusting mechanism cannot handle it.
Further, in the conventional head gap adjusting mechanism, the guide shaft 3 has to be rotatably mounted on the frame, so that the guide shaft 3 cannot be used as a strength member of the frame, and the frame becomes expensive, and the carrier is A stepping motor must be used as a motor for raising and lowering, which increases the cost of parts and complicates control.

Also, regarding the capping mechanism of the ink jet head, the mechanism of the conventional structure is very complicated, and if a capping mechanism of the same structure is adopted for the stamp device, the structure becomes complicated and the cost of the device becomes high. Become.

The present invention was made as part of research and development aiming at obtaining a stamping device capable of stamping various designs on a mail item, and is provided between a print head and a printing surface. Obtaining a head gap adjusting mechanism with a simple structure that can quickly set the interval according to the thickness of each printed material, and using the operation of this head gap adjusting mechanism makes capping of the inkjet head extremely easy. It is an object to obtain a stamp device that can be realized with a simple structure.

[0011]

A stamp device according to a first aspect of the present invention is a stamp shaft 3 having both ends fixed to side walls of a frame.
A print head 1 mounted on a carrier that runs along the guide shaft; a paper table 9 that is vertically movable below the print head; and a spring 18 that biases the paper table upward. It is provided with a stopper 22 that comes into contact with the upper surface of the paper tray 9 with a predetermined head gap left between the tip of the print head 1 and a pressing mechanism 19 that pushes the paper tray 9 downward. It is what

According to a second aspect of the present invention, there is provided the stamp device according to the first aspect.
In the stamp device described above, guide plates 11 and 12 are provided on the back side of the paper tray 9 and on either side thereof, and the paper detection switch 13 is arranged at the intersection of the guide plates 11 and 12. It is characterized by.

According to a third aspect of the present invention, there is provided a stamp head which is fixed in a height direction and is movable along a guide shaft 3 between a home position and a print area.
A paper table 9 that moves in a direction in which it is close to and away from the print head
And a capping mechanism 23 for the print head that advances and retracts in a direction opposite to the approaching and separating operation of the paper table.

[0014]

According to the first aspect of the present invention, a gap sensor is not required, an inexpensive DC motor can be used as a drive motor when setting the print gap, and control is extremely simple, and therefore inexpensive. At the same time, it is possible to obtain a stamping device that can quickly set a constant print gap for a wide variety of printing papers. Also, since the guide shaft of the carrier on which the print head is mounted can be used as a strength member that reinforces the frame,
The frame can also have a lightweight and inexpensive structure. Further, since the print gap is defined by the stoppers arranged on both sides of the limited printing area, even if the medium has a so-called step difference, the thickness is partially different,
Accurate print gap setting is possible. Further, by adopting the structure of claim 3, the capping mechanism of the print head when the ink jet head is used as the print head becomes simple.

According to the second aspect of the present invention, when the sheet is inserted at an angle, the sheet is not detected and therefore the stamp printing operation is not performed either. Therefore, the stamp is printed at an accurate position on the sheet in an accurate posture. It is possible to provide a stamp device capable of performing the above.

According to the third aspect of the present invention, in a stamping device using an ink jet head, it is possible to obtain a stamping device that has a simple capping mechanism for the print head when not in use and that operates reliably.

[0017]

1 is a perspective view showing a stamp device to which the present invention is applied. The carrier 2 on which the print head 1 is mounted can travel in the left-right direction in the figure by the guide shaft 3 and the guide bar 4 arranged below the guide shaft 3.
The carrier 2 is provided with two short guide rods 5 extending to the front side above the carrier 2, and a holder 6 having the print head 1 mounted thereon is slidably supported by the guide rods 5. A screw shaft 7 which is cantilevered on the carrier 2 and is screwed onto the upper end of the holder 6 is provided at an intermediate position between the two guide rods 5. The screw shaft 7 is driven by a motor 8.
By rotating the, the holder 6 and hence the print head 1 moves in the front-back direction. The movement of the print head 1 in the front-rear direction is provided so that a stamp having a width larger than the print width of the print head 1 can be printed.

Below the print head 1, a rectangular flat paper tray 9 is arranged. Guide plates 11 and 12 are provided at the back side and the right side of the figure of the base plate on which the paper base 9 is mounted, and paper detection switches 13 are arranged at the corners of both guide plates 11 and 12. . A capping mechanism including a cap 14 of the print head is arranged on the right side of the paper table 9 in the figure. The reduction gear train 15 arranged on the right side of the drawing is for rotating a cam shaft 16 described later, and is connected to a cam motor 17 (see the drawing). An inexpensive DC motor can be used as the cam motor 17.

FIG. 2 is a view showing the head gap setting mechanism of the present invention. In the structure of the present invention, the print head 1
The guide shaft 3 that guides the frame is fixed to both side walls of the frame and the guide shaft 3 is used as a strength member that reinforces the frame. Therefore, the print head 1 cannot move up and down.

The paper table 9 facing the print head 1 is provided with a spring 18 biased upward, and a cam 19 is arranged below the paper table 9. The cam 19 is the paper tray 9
Is engaged with the tip of a push rod 21 extending downward from the lower surface of the press lever 21 and the cam 19 is rotated counterclockwise around the cam shaft 16 to push down the push rod 21 and lower the paper tray 9.

Stoppers 22 are fixed to the frame at positions on both sides of the print head 1 above the paper tray 9. As for this stopper 22, the paper table 9 has a spring 18
When it collides with the lower surface of the stopper 22 due to the force of, the distance between the upper surface of the paper tray 9 and the tip of the print head 1 becomes a predetermined print gap. The cam shaft 16 is
It is connected to the cam motor 17 via the gear train 15 described above.

FIG. 3 shows the relationship between the guide plates 11 and 12 provided on the back and right sides of the paper tray and the paper detection switch 13. The paper detection switch 13 has two orthogonal guide plates. It is provided at the intersection of 11 and 12. With this structure, only when the paper (envelope) is accurately abutted against both the guide plates 11 and 12, the corner of the paper operates the paper detection switch 13 to detect the paper.

The print head 1 of the illustrated embodiment is an ink jet head and its capping mechanism is shown in FIG. When the carrier 2 moves rightward and reaches the home position, the print head 1 is located above the capping mechanism 23. The capping mechanism 23 includes a cap 14 that is vertically moved by a second cam 24 that is fixed to a cam shaft 16 of a cam that lowers the paper tray, and the second cam 24 operates in conjunction with the lowering operation of the paper tray 9. The structure is such that the cap 14 is pushed up.

In the illustrated embodiment, the same camshaft 16
Although the lowering of the paper table 9 and the upward movement of the cap 14 are interlocked with each other by the phase relationship between the cam 19 and the second cam 24 fixed to each other, the paper base 9 and the cap 14 are interlocked by using a seesaw lever or the like. It is also possible to have a structure that allows it.

Next, the operation of the apparatus described above will be described. When the paper (envelope) 25 is placed on the paper tray 9 and abutted against the two guide plates 11 and 12, the paper detection switch 13 detects the corner of the paper 25, rotates the cam motor 17, and causes the cam 19 to rotate. Is rotated to the right in FIG. This cam 1
As the sheet 9 is rotated clockwise, the sheet tray 9 is pushed upward by the spring 18, and the upper movement of the sheet tray 9 is stopped at the position where the upper surface of the sheet 25 contacts the stopper 22. In this state, a predetermined print gap is set between the upper surface of the paper and the tip of the print head.

Next, the print head 1 scans the marking area of the stamp by the horizontal movement of the carrier 2 along the guide shaft 3 and the forward and backward movement of the holder 6 on the guide rod 5 extending forward from the carrier 2. , Print the stamp of the selected design.

When printing is completed, the print head 1 returns to the home position, the cam motor 17 is driven, and the cam 19 rotates left in FIG. 2 to lower the paper tray 9. The second cam 24 moves the cap 14 upward in conjunction with this lowering operation, and the cap 1 is attached to the print head that has returned to the home position.
Cover 4

[0028]

According to the present invention, the mechanism for adjusting the head gap is simple, stamps of various designs can be printed at accurate positions on the paper, and the guide shaft of the carrier of the print head serves as a strength member for reinforcing the frame. It is possible to use the stamping device, and thus to realize the stamping device which avoids the price increase of the frame. Also, in a stamping device using an inkjet head as a print head, a stamping device that can quickly perform capping operation of the print head when not in use, has stable operation, and has a simple structure is provided. The effect is that you can do it.

[Brief description of drawings]

FIG. 1 is a perspective view showing a stamp device.

FIG. 2 is a side view showing an elevating mechanism of a paper tray.

FIG. 3 is a plan view showing the position of the paper detection device.

FIG. 4 is a schematic view showing a capping mechanism.

FIG. 5 is a schematic diagram showing a conventional print gap setting mechanism.

FIG. 6 is a schematic diagram showing a conventional capping mechanism.

[Explanation of symbols]

 1 print head 2 carrier 3 guide shaft 9 paper tray 11 guide plate 12 guide plate 13 paper detection switch 18 spring 19 cam 22 stopper 23 capping mechanism

Claims (3)

[Claims] 1. A guide shaft (3) having both ends fixed to a side wall of a frame, a print head (1) mounted on a carrier running along the guide shaft, and a print shaft (3) arranged vertically below the print head. Paper tray (9), the spring (18) that urges the paper tray upward, and the leading edge of the print head (1) leave a predetermined head gap between the paper tray (9). A stamping device comprising a stopper (22) that comes into contact with the upper surface and a pressing mechanism (19) that presses the paper tray (9) downward. 2. A guide plate (11, 12) is provided on the back side of the paper table (9) and either one of the left and right sides thereof, and a paper detection switch is provided at the intersection of the both guide plates (11, 12). The stamp device according to claim 1, wherein (13) is arranged. 3. A print head (1) having a fixed height position and movable between a home position and a print area along a guide shaft (3), and a direction in which the print head is moved toward and away from the print head. A stamping device comprising a paper table (9) that moves to the front and back, and a print head capping mechanism (23) that advances and retracts in a direction opposite to the approaching and separating operation of the paper table.