Piezoelectric ink jet device

Abstract

The utility model belongs to the technical field of ink-jet printing, and relates to a piezoelectric ink-jet device. The piezoelectric ink-jet device comprises a glass guide plate, a piezoelectric driving plate and a nozzle plate which are connected in sequence, the glass flow guide plate and the piezoelectric driving plate are provided with microgrooves, the nozzle plate is provided with micropores, and the microgrooves in the glass flow guide plate, the microgrooves in the piezoelectric driving plate and the micropores in the nozzle plate are communicated to form an ink flow channel; and the piezoelectric driving plate deforms by utilizing a piezoelectric effect so as to realize ink injection. According to the piezoelectric ink-jet device, the piezoelectric effect is utilized, ink jet is achieved through a multi-layer structure, relatively short flow channels are arranged, pressure can be conducted more effectively in the ink channels, meanwhile, all the flow channels are concentrated in the same piezoelectric driving plate, splicing is not needed, the whole driving structure is simplified, manufacturing links are reduced, and the manufacturing cost is reduced. And the qualified rate of products is greatly improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of inkjet printing, and in particular relates to a piezoelectric inkjet device. Background Art

[0002] Usually, inkjet print heads print ink droplets onto designated areas of the medium to present a printed color image on the print medium. There are two types of inkjet print heads: thermal bubble inkjet technology and piezoelectric inkjet technology. Thermal bubble inkjet technology uses the instantaneous heating of the thermal resistor around the nozzle to generate bubbles in the ink, and uses the expansion of the bubbles to spray the ink, while piezoelectric inkjet technology uses the deformation of piezoelectric materials under high voltage to pressurize the ink and spray it out.

[0003] The existing piezoelectric inkjet technology has a relatively long flow channel, which makes it difficult for pressure to be transmitted more effectively in the ink channel. At the same time, the overall driving structure is complex and there are many manufacturing links, which reduces the product qualification rate. Utility Model Content

[0004] The utility model aims at solving the above problems and provides a piezoelectric inkjet device.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A piezoelectric inkjet device comprises a glass guide plate, a piezoelectric driving plate and a nozzle plate which are connected in sequence; the glass guide plate and the piezoelectric driving plate are provided with microgrooves, the nozzle plate is provided with micropores, the microgrooves on the glass guide plate are connected with the microgrooves on the piezoelectric driving plate and the micropores on the nozzle plate to form an ink flow channel; the piezoelectric driving plate utilizes the piezoelectric effect to deform to realize ink ejection.

[0007] Furthermore, the piezoelectric driving plate is made of piezoelectric material, and the piezoelectric material includes piezoelectric ceramics.

[0008] Furthermore, the piezoelectric drive plate is formed by horizontally stacking one or two piezoelectric ceramics, and all microgrooves serving as ink flow channels are arranged in order and are within the same piezoelectric drive plate without the need for splicing.

[0009] Furthermore, the piezoelectric driving plate utilizes the piezoelectric effect to deform to achieve ink ejection, including two methods: first, using the side wall of the microgroove as a driving source, and achieving ink ejection through the deformation of the piezoelectric ceramic in the D15 direction; second, using the interval between two adjacent microgrooves as a driving source, and achieving ink ejection through the deformation of the piezoelectric ceramic in the D33 direction.

[0010] Furthermore, the glass guide plate and the piezoelectric driving plate are both provided with metal electrodes.

[0011] Further, the metal electrode is prepared by a metallization process, and the metallization process is a vacuum coating process or an electroless plating process.

[0012] Further, the glass flow guide plate is provided with 2 rows of 128 micro-grooves each; the piezoelectric drive plate is provided with 2 rows of 128 micro-grooves each, and corresponds to the 2 rows of 128 micro-grooves on the glass flow guide plate one by one, or the piezoelectric drive plate is provided with 2 rows of 256 micro-grooves each, and every other micro-groove corresponds to the micro-grooves on the glass flow guide plate.

[0013] Further, the piezoelectric drive plate is provided with double-row staggered micro-grooves or quadruple-row staggered micro-grooves.

[0014] Further, the material of the nozzle plate is PI, stainless steel foil or silicon.

[0015] Further, the piezoelectric inkjet device further includes:

[0016] A nozzle plate protective cover for protecting the nozzle plate;

[0017] A drive circuit board connected to the glass flow guide plate with conductive adhesive for providing drive signals;

[0018] An ink path connected to the glass flow guide plate to form a sealed ink storage chamber;

[0019] A plug connected to both ends of the ink path for sealing the ink path;

[0020] A data adapter board connected to the printing device for receiving print signals and data;

[0021] A bracket connected to the data adapter board for fixing the data adapter board and the drive circuit board;

[0022] An ink inlet connected to the ink path for supplying ink to the ink storage chamber;

[0023] A housing for protecting the internal circuit of the piezoelectric inkjet device from being eroded by ink.

[0024] The beneficial effects of the present utility model are as follows:

[0025] The piezoelectric inkjet device of the present utility model adopts a multi-layer structure, including a glass flow guide plate, a piezoelectric drive plate and a nozzle plate to realize the overall piezoelectric jet structure. The piezoelectric inkjet device has a relatively short flow path, which can make the pressure be more effectively conducted in the ink channel, and all the flow paths are concentrated in the same piezoelectric drive plate without splicing, simplifying the overall drive structure, reducing the manufacturing links, and greatly improving the qualified rate of the product. Description of the Drawings

[0026] Figure 1It is a schematic structural diagram of the piezoelectric inkjet device of the present utility model.

[0027] Figure 2 It is a schematic diagram of two rows of micro-grooves machined on the piezoelectric drive plate.

[0028] Figure 3 It is a schematic diagram of four rows of micro-grooves arranged in a staggered manner on the piezoelectric drive plate.

[0029] Figure 4 It is a schematic cross-sectional view of the assembled glass flow guide plate, piezoelectric drive plate and nozzle plate. Specific embodiments

[0030] The present utility model will be further described in detail below through specific embodiments.

[0031] The piezoelectric inkjet device of the present utility model includes a glass flow guide plate, a piezoelectric drive plate and a nozzle plate. The function of the glass flow guide plate is to control the ink flow direction and transfer the electrode signals of the piezoelectric arms on the piezoelectric drive plate (the piezoelectric structure between two micro-grooves on the piezoelectric drive plate is called a piezoelectric arm). The piezoelectric drive plate has the functions of deformation and ink path circulation. The nozzle plate can be made of different materials such as PI (polyimide), stainless steel foil, silicon, etc. by different processes. Such a three-layer structure realizes the jetting function.

[0032] The glass flow guide plate includes the inlet of the ink flow path and metal electrode wiring, which can be realized by micro-blasting, laser, ultrasonic and other processing methods. The metal electrode wiring is realized by MEMS process, photolithography pattern and metallization, stripping process, etc. The metallization process is realized by vacuum coating or electroless plating.

[0033] The processing of the piezoelectric drive plate can be realized by high-precision ultrasonic machine tools, laser and other technologies, or by die pressing and then sintering, etc., and the electrodes are prepared by metallization process. The metallization process is realized by vacuum coating or electroless plating. The piezoelectric drive plate can use piezoelectric materials such as PZT, and vertical through-holes, that is, micro-grooves, are opened on the horizontal piezoelectric drive plate. When the side wall of the micro-groove is used as the driving source, the shear mode is used, and the jetting is realized by the deformation of the edge of the groove. At this time, the D15 direction of the piezoelectric ceramic is used. When the interval between two micro-grooves is used as the driving source, the deformation in the D33 direction of the piezoelectric ceramic is used to realize the jetting.

[0034] The processing technology of the nozzle plate can be realized by etching, laser processing, stamping, electroplating and other methods.

[0035] Figure 1It is a schematic structural diagram of the piezoelectric inkjet device of the present utility model, including a glass flow guide plate 401, a piezoelectric drive plate 301, and a nozzle plate 201. Among them, the piezoelectric drive plate 301 and the nozzle plate 201 are bonded together. In addition, it also has the following structures:

[0036] A nozzle plate protective cover 101, used to protect the nozzle plate 201;

[0037] A drive circuit board 501, connected to the glass flow guide plate 401 with conductive glue, used to provide a drive signal to the piezoelectric actuator (i.e., the overall structure assembled by the glass flow guide plate, the piezoelectric drive plate, and the nozzle plate);

[0038] A plug 502, connected to both ends of the ink path 503, used to seal the ink path;

[0039] An ink path 503, connected to the glass flow guide plate 401 to form a sealed ink reservoir;

[0040] A bracket 601, connected to the data transfer board 801, used to fix the data transfer board 801 and the drive circuit board 501;

[0041] An ink inlet 701, connected to the ink path 503, used to supply ink to the ink reservoir;

[0042] A data transfer board 801, connected to the printing device, used to receive printing signals and data;

[0043] A housing 901, connected to the ink path 503 to form a closed housing, protecting the internal circuit from being eroded by ink.

[0044] In one embodiment of the present utility model, the following steps are adopted to prepare the piezoelectric inkjet device:

[0045] 1) The outer dimensions of the glass flow guide plate 401: A glass sheet with dimensions of 60X12X0.5 (mm) is used. On this glass sheet, 2 rows of 128 micro-grooves are processed. The dimensions of the micro-grooves are 0.8X0.08 (mm), and the micro-grooves are penetrating. The micro-grooves are formed by a combination of micro-blasting and laser processes. The micro-grooves are conical in shape, wider at the top and narrower at the bottom for facilitating liquid flow.

[0046] Then, a spray coater is used to spray photoresist onto the glass surface. After processes such as photolithography, metallization, and stripping, a metal wiring line connected to the piezoelectric actuator (i.e., the overall structure assembled by the glass flow guide plate, the piezoelectric drive plate, and the nozzle plate) and the external circuit is fabricated.

[0047] 2) The piezoelectric drive plate 301 is made of single-layer or double-layer piezoelectric ceramics. Micro-grooves are machined perpendicular to the piezoelectric plate, and the micro-grooves are made by ultrasonic grinding or laser forming processes. The size of the micro-grooves is 2X0.1 (mm), and two rows of 128 through-grooves are machined, which correspond one-to-one with the two rows of 128 micro-grooves on the glass flow guide plate 401 at this time; or two rows of 256 through-grooves can also be machined, and at this time, every other groove corresponds to the two rows of 128 micro-grooves on the glass flow guide plate 401 (referred to as interval correspondence). It is required that the flatness of the side walls of the micro-grooves is less than 0.3 microns, and the parallelism of the surface of the piezoelectric drive plate is less than 3 microns. Figure 2 It is a schematic diagram of the micro-grooves on the piezoelectric drive plate, which are micro-grooves arranged in a double-row staggered manner. Figure 2 The right side shows the size of the micro-grooves. In other embodiments, the micro-grooves on the piezoelectric drive plate 301 can also be micro-grooves arranged in a four-row staggered manner, as Figure 3 shown.

[0048] 3) The nozzle plate 201 is made of PI material and formed by laser micro-machining technology. Micropores are provided on the nozzle plate 201 for inkjet.

[0049] 4) A 0.2-mm stainless steel foil is selected and formed by stamping as the nozzle plate protection cover 101.

[0050] 5) Clean and prepare the drive circuit board 501 of the inkjet head with the outer shape processed. Assemble the glass flow guide plate 401 and the piezoelectric drive plate 301 with conductive adhesive, and then bond the nozzle plate 201 to the other side of the piezoelectric drive plate 301 with adhesive. At this time, assemble and press-weld the drive circuit board 501 to the metal wire rows on both sides of the glass flow guide plate 401 through the conductive adhesive. Figure 4 It shows the assembled glass flow guide plate 401, piezoelectric drive plate 301 and nozzle plate 201. The micro-grooves on the glass flow guide plate 401 correspond to the micro-grooves on the piezoelectric drive plate 301 and the micropores on the nozzle plate 201 to form an ink flow channel.

[0051] 6) Then encapsulate the assembled module with the plastic ink path 503 with adhesive. Seal both sides of the ink path 503 with plugs 502, and bond the metal pipe fittings of the ink inlet 701 with glue.

[0052] 7) Insert the connector of the data transfer board 801 into the connector of the drive circuit board 501, then install the housing 901 and seal it with glue.

[0053] 8) Install the nozzle plate protection cover 101 and bond it with glue.

[0054] The specific embodiments of the present utility model disclosed above are intended to help understand the content of the present utility model and implement it accordingly. Those of ordinary skill in the art can understand that various substitutions, changes, and modifications are possible without departing from the spirit and scope of the present utility model. The present utility model should not be limited to the content disclosed in the embodiments of this specification, and the protection scope of the present utility model shall be subject to the scope defined by the claims.

Claims

1. A piezoelectric inkjet device, characterized in that, It includes a glass flow guide plate, a piezoelectric drive plate, and a nozzle plate connected in sequence; microgrooves are provided on the glass flow guide plate and the piezoelectric drive plate, and micropores are provided on the nozzle plate. The microgrooves on the glass flow guide plate, the microgrooves on the piezoelectric drive plate, and the micropores on the nozzle plate are connected to form an ink flow path; the piezoelectric drive plate deforms by using the piezoelectric effect to achieve ink jetting.

2. The piezoelectric inkjet device according to claim 1, wherein, The piezoelectric drive plate is made of a piezoelectric material, and the piezoelectric material includes piezoelectric ceramics.

3. The piezoelectric inkjet device according to claim 2, wherein The piezoelectric drive plate is composed of 1 or 2 pieces of piezoelectric ceramics horizontally stacked and compounded. All the microgrooves serving as the ink flow path are arranged orderly and within the same piezoelectric drive plate without splicing.

4. The piezoelectric inkjet device according to claim 1, characterized in that, The piezoelectric drive plate deforms by using the piezoelectric effect to achieve ink jetting, including two methods: First, using the side wall of the microgroove as the drive source, and achieving ink jetting through the deformation of the piezoelectric ceramic in the D15 direction; Second, using the interval between two adjacent microgrooves as the drive source, and achieving ink jetting through the deformation of the piezoelectric ceramic in the D33 direction.

5. The piezoelectric inkjet device according to claim 1, wherein Both the glass flow guide plate and the piezoelectric drive plate are provided with metal electrodes.

6. The piezoelectric inkjet device according to claim 5, wherein, The metal electrode is prepared by a metallization process, and the metallization process is a vacuum coating process or a chemical plating process.

7. The piezoelectric inkjet device according to claim 1, wherein There are 2 rows of 128 microgrooves each on the glass flow guide plate; there are 2 rows of 128 microgrooves each on the piezoelectric drive plate, and they correspond one by one to the 2 rows of 128 microgrooves on the glass flow guide plate, or there are 2 rows of 256 microgrooves each on the piezoelectric drive plate, and every other microgroove corresponds to the microgrooves on the glass flow guide plate.

8. The piezoelectric inkjet device according to claim 1, wherein, The piezoelectric drive plate is provided with double-row staggered microgrooves or quadruple-row staggered microgrooves.

9. The piezoelectric inkjet device according to claim 1, wherein, The nozzle plate is made of PI, stainless steel foil, or silicon.

10. The piezoelectric inkjet device according to any one of claims 1 to 9, characterized in that, It further includes: A nozzle plate protection cover for protecting the nozzle plate; A drive circuit board connected to the glass flow guide plate with conductive glue for providing drive signals; An ink path connected to the glass flow guide plate to form a sealed ink storage; A plug connected to both ends of the ink path for sealing the ink path; A data transfer board connected to the printing device for receiving printing signals and data; A bracket connected to the data transfer board for fixing the data transfer board and the drive circuit board; An ink inlet connected to the ink path for supplying ink to the ink storage; A housing for protecting the internal circuit of the piezoelectric inkjet device and preventing it from being eroded by ink.

Images