Key structure and thermal printer with same
By using elastic parts to support the PCB board in the key structure of the thermal printer, the problem of difficult to control the tightness of the buttons and switches is solved, and stable contact force and optimal operating sense are achieved.
Patent Information
- Application Number
- CN202420103399.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-16
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-01-16
AI Technical Summary
The tightness between the keys and switches of existing thermal printers is difficult to control, which causes the switch to be turned on when the fit is too tight, and the keys to shake when they are loose, affecting the overall experience.
A structure including a base, a cover plate, a PCB plate and a button is designed. A bracket and a hollow mounting groove are provided on the base. Elastic parts are placed in the groove to support the PCB plate. There are convex columns acting on the switch at the lower end of the button, and the upper end has steps. To limit disengagement, ensure stable contact and adjust tightness.
With the support of the elastic parts, the stable contact force between the PCB board and the button is maintained, and the tightness is automatically adjusted, which improves the operating feeling and overall experience of the button.
Smart Images
Figure CN222260856U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a switch button structure, which can be applied to a thermal printer. The utility model also relates to a printing device. Background Art
[0002] At present, the paper feeding and functions of thermal printers are generally completed by independent key switches (pressing the circuit to turn on, releasing the circuit to turn off). Figure 1 As shown in the figure, a common key switch design includes a key 2a made of plastic and a PCB board 3a. The PCB board 3a is fixed to the inner side of the cover plate 11a by screws 5a. The cover plate 11a is arranged on the base and has a mounting hole 12a. The key 2a is located in the mounting hole 12a for operation. The switch 4a is welded on the PCB board 3a. When the key 2a is pressed, the switch 4a is triggered and the circuit is turned on. Such a structure has the following defects: the tightness between the key and the switch is difficult to control. If the fit is too tight, it is easy for the switch to be always in the pressed-on state; if the fit is too loose, the key will shake, affecting the overall experience, so it needs to be improved. Utility Model Content
[0003] The first technical problem to be solved by the utility model is to provide a key structure with good tightness between a key and a switch in view of the above technical status.
[0004] The second technical problem to be solved by the utility model is to provide a thermal printer, wherein the keys and switches of the thermal printer have good tightness.
[0005] The technical solution adopted by the utility model to solve the above-mentioned first technical problem is: a key structure, including a base;
[0006] A cover plate, which is arranged on the aforementioned base and has a mounting hole;
[0007] A PCB board is arranged in the space formed by the aforementioned base and the cover plate, and has a switch on its upper end surface; and
[0008] A button is arranged in the mounting hole of the cover plate and the bottom of the button can abut against the switch. When the button is pressed, the switch can be triggered, thereby conducting the circuit.
[0009] It is characterized in that the base is provided with a bracket, the middle part of the bracket is hollowed out to form a mounting groove, an elastic member is arranged in the mounting groove, and the PCB board is limitedly located on the bracket and the lower end surface is against the elastic member.
[0010] Furthermore, a protrusion extends downward from the lower end surface of the button, and the protrusion can act on the switch.
[0011] The matching structure between the key and the mounting hole is as follows: the upper end surface of the key has a step portion, and the step portion can be limited in the mounting hole to limit the key from leaving the mounting hole.
[0012] Preferably, the elastic member is a spring.
[0013] The PCB board positioning structure is preferably configured as follows: both sides of the PCB board have limiting grooves, and correspondingly, both sides of the bracket have limiting protrusions adapted to the aforementioned limiting grooves.
[0014] The technical solution adopted by the utility model to solve the first technical problem is: a thermal printer with the aforementioned key structure, comprising
[0015] A transmission gear set is rotatably arranged on the base;
[0016] A motor is arranged on the base and has an output gear at its power output end meshing with the power input end of the transmission gear set;
[0017] A cover plate, which can be arranged on the aforementioned base in a covering manner;
[0018] A rubber roller assembly is rotatably disposed inside the aforementioned cover plate and comprises a rubber roller, a central shaft and an input gear disposed at the end of the central shaft, wherein the aforementioned central shaft penetrates the rubber roller, and the aforementioned input gear can mesh with the power output end of the aforementioned transmission gear set for transmission; and
[0019] The print head assembly is arranged on the base, and both ends of the print head assembly are provided with shaft grooves for the central shaft to rotate.
[0020] Compared with the prior art, the advantages of the utility model are: the elastic member is supported under the PCB board, and can always give the PCB board an upward force, so that the contact force between the PCB board and the key can be kept stable and reliable, and the elastic member can automatically complete the force adjustment of the PCB board and the key to achieve the best tightness and the key operation feel is also better. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is a schematic diagram of the structure of a thermal printer in the prior art.
[0022] Figure 2 for Figure 1 Exploded diagram of .
[0023] Figure 3 Schematic diagram of the appearance of a thermal printer in an embodiment.
[0024] Figure 4 for Figure 3 Exploded diagram of .
[0025] Figure 5 for Figure 4An enlarged view of the PCB board.
[0026] Figure 6 for Figure 4 Enlarged view of part A in the middle.
[0027] Figure 7 It is a combination diagram of the cover plate and rubber roller assembly.
[0028] Figure 8 It is an enlarged three-dimensional cross-sectional view of an embodiment. DETAILED DESCRIPTION
[0029] The present invention will be described in further detail below in conjunction with the accompanying drawings.
[0030] like Figure 3 , Figure 4 and Figure 7 As shown, the thermal printer in this embodiment includes a base 1, a transmission gear set 91, a motor 9, a cover plate 6, a rubber roller assembly 5, a print head assembly 8, a cover plate 2, a PCB board 4 and a button 3.
[0031] The transmission gear set 91 is rotatably arranged on the base 1; the motor 9 is arranged on the base 1 and has an output gear at the power output end that meshes with the power input end of the transmission gear set 91 for transmission; the cover plate 6 is arranged on the base 1 in a covering manner; the rubber roller assembly 5 is rotatably arranged on the inner side of the cover plate 6 and includes a rubber roller 51, a central axis 52 and an input gear 53 arranged at the end of the central axis 52, the central axis 52 passes through the rubber roller 51, and the input gear 53 can mesh with the power output end of the transmission gear set 91 for transmission; the print head assembly 8 is arranged on the base 1, and the two ends of the print head assembly 8 have shaft grooves 81 for the central axis 52 to be rotatably arranged.
[0032] Combination Figure 5 and Figure 8 As shown, the cover plate 2 is arranged on the base 1 and has a mounting hole 21, and a decorative plate 22 is also arranged on the outer side of the cover plate 2. The PCB board 4 is arranged in the space formed by the base 1 and the cover plate 2, and a switch 41 is arranged on the upper end surface; the button 3 is arranged in the mounting hole 21 of the cover plate 2 and the bottom can be against the switch 41. The button 3 can touch the switch 41 when pressed, and then the circuit is turned on, the motor works, and the transmission gear set drives the rubber roller to rotate.
[0033] Combination Figure 6 As shown, the base 1 has a bracket 7, and the middle part of the bracket 7 has a hollow installation groove 71, and an elastic member 43 is arranged in the installation groove 71. The PCB board 4 is limited on the bracket 7 and the lower end surface is against the elastic member 43. In order to further provide stability for the PCB board, it can also be fixed to the inner side of the cover plate 2 by screws.
[0034] Combination Figure 8As shown, a boss 32 extends downward from the lower end surface of the button 3, and the boss 32 can act on the switch 41. The upper end surface of the button 3 has a step portion 31, and the step portion 31 can be limited in the mounting hole 21 to limit the button 3 from being separated from the mounting hole 21. The elastic member 43 in this embodiment is a spring, and other elastic components can also be used. Both sides of the PCB board 4 have limit grooves 42, and correspondingly, both sides of the bracket 7 have limit convex portions 72 adapted to the limit grooves 42.
[0035] The spring as an elastic part is supported under the PCB board, which can always give the PCB board an upward force, so that the contact force between the PCB board and the key can remain stable and reliable. The elastic part can automatically adjust the force between the PCB board and the key to achieve the best tightness and the key operation feel is also better.
Claims
1. A key structure, comprising Base (1); A cover plate (2) is disposed on the base (1) and has a mounting hole (21); A PCB board (4) is arranged in the space formed by the base (1) and the cover plate (2), and has a switch (41) on its upper end surface; and A button (3) is arranged in the mounting hole (21) of the cover plate (2) and the bottom of the button (3) can abut against the switch (41). When the button (3) is pressed, the switch (41) can be triggered, thereby conducting the circuit. Features The base (1) is provided with a bracket (7), the middle part of the bracket (7) is provided with a hollow installation groove (71), an elastic member (43) is arranged in the installation groove (71), and the PCB board (4) is limitedly positioned on the bracket (7) and the lower end surface is against the elastic member (43).
2. The key structure according to claim 1, characterized in that A convex column (32) extends downward from the lower end surface of the button (3), and the convex column (32) can act on the switch (41).
3. The key structure according to claim 1, characterized in that The upper end surface of the button (3) has a step portion (31), and the step portion (31) can be limited in the mounting hole (21) to limit the button (3) from leaving the mounting hole (21).
4. The key structure according to claim 1, characterized in that The elastic member (43) is a spring.
5. The key structure according to claim 1, characterized in that Both sides of the PCB board (4) are provided with limiting grooves (42), and correspondingly, both sides of the bracket (7) are provided with limiting protrusions (72) adapted to the aforementioned limiting grooves (42).
6. A thermal printer having a key structure as claimed in any one of claims 1 to 5, comprising A transmission gear set (91) is rotatably disposed on the base (1); The motor (9) is arranged on the base (1) and has an output gear at its power output end that meshes with the power input end of the transmission gear set (91); A cover plate (6) is arranged on the aforementioned base in a coverable manner; A rubber roller assembly (5) is rotatably disposed inside the aforementioned cover plate (6) and comprises a rubber roller (51), a central shaft (52) and an input gear (53) disposed at the end of the central shaft (52), wherein the aforementioned central shaft (52) penetrates the rubber roller (51), and the aforementioned input gear (53) can mesh with the power output end of the aforementioned transmission gear set (91) for transmission; and The print head assembly (8) is arranged on the base (1), and both ends of the print head assembly (8) are provided with shaft grooves (81) for the central shaft (52) to be rotatably arranged.