CN215215299U

CN215215299U - Hydraulic buffer and ink jet numbering machine

Info

Publication number: CN215215299U
Application number: CN202121478204.8U
Authority: CN
Inventors: 张会波
Original assignee: Xuchang Delike Electronic Machinery Technology Co ltd
Current assignee: Xuchang Delike Electronic Machinery Technology Co ltd
Priority date: 2021-06-30
Filing date: 2021-06-30
Publication date: 2021-12-17
Anticipated expiration: 2031-06-30

Abstract

The utility model discloses a hydraulic buffer, the pressure fluctuation can be eliminated on the one hand to its one side, guarantees pressure stability, and on the other hand hydraulic buffer has switch function, can use in the ink supply system of ink jet numbering machine, as an overvoltage protection system's a part. A hydraulic buffer comprises a buffer box, an isolating device and a hydraulic oil tank, wherein the buffer box is provided with a cavity and an ink inlet, the ink inlet is communicated with the cavity, the isolating device is connected with the buffer box and isolates the cavity into a medium cavity and an inner cavity, a pressure spring is arranged in the inner cavity, the upper end of the pressure spring is abutted against the buffer box, and the lower end of the pressure spring is abutted against the bottom of the isolating device; the first contact device and the second contact device are fixed with the buffer box, the first contact device and the second contact device are in contact with the conductive connection device after the inner cavity space is reduced to form triggered electric connection, and the first contact device and the second contact device are disconnected from the electric connection after the inner cavity space is enlarged.

Description

Hydraulic buffer and ink jet numbering machine

Technical Field

The utility model belongs to the technical field of ink jet numbering machine.

Background

Ink is the medium in which the ink supply system of an ink jet printer operates. When the code spraying machine works, ink circulates in an internal pipeline of an ink supply system and an ink bottle all the time, and kinetic energy of ink circulation is provided by a pressure pump arranged in the ink supply system. However, the hydraulic pressure supplied by the pressure pump is pulsating, and in addition, the ink is influenced by the density and others in the piping, and the flow rate occasionally varies, eventually resulting in unstable pressure in the ink system. In order to ensure the stable pressure of the ink inside the ink supply system, the existing ink system adopts an elastic shell made of an elliptical non-metallic material, and the elastic shell deforms to absorb the fluctuating pressure when the pressure exists, so that the stable pressure inside the ink supply system is achieved.

In the process of ink supply system operation, the elastic shell is always in the expanded state under the action of ink pressure. On the other hand, the elastic shell is easily corroded due to long-term contact with ink, and the service life is short. When the pipeline of the ink supply system is blocked, the elastic shell can not play the roles of opening and closing and detecting, and the pressure pump still keeps working, so that the pressure in the ink supply system is overhigh, and the parts are damaged.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a hydraulic buffer, the pressure fluctuation can be eliminated on the one hand to its one side, guarantees pressure stability, and on the other hand hydraulic buffer has switch function, can use in the ink supply system of ink jet numbering machine, as an overvoltage protection system's a part.

In order to solve the technical problem, the utility model discloses a technical scheme is:

a hydraulic buffer comprises a buffer box, an isolating device and a hydraulic oil tank, wherein the buffer box is provided with a cavity and an ink inlet, the ink inlet is communicated with the cavity, the isolating device is connected with the buffer box and isolates the cavity into a medium cavity and an inner cavity, a pressure spring is arranged in the inner cavity, the upper end of the pressure spring is abutted against the buffer box, and the lower end of the pressure spring is abutted against the bottom of the isolating device; the first contact device and the second contact device are fixed with the buffer box, the first contact device and the second contact device are in contact with the conductive connection device after the inner cavity space is reduced to form triggered electric connection, and the first contact device and the second contact device are disconnected from the electric connection after the inner cavity space is enlarged.

On the basis of the above scheme and as a preferable scheme of the scheme: the isolating device is a corrugated pipe, the first contact device is inserted into the inner cavity, the bottom end of the first contact device is in contact with the conductive connecting device after the corrugated pipe is compressed, the bottom end of the first contact device is not in contact with the conductive connecting device when the corrugated pipe is in an extending state, and the second contact device is in contact with the conductive connecting device.

On the basis of the above scheme and as a preferable scheme of the scheme: the isolating device is a corrugated pipe, the first contact device and the second contact device are inserted into the inner cavity, the bottom ends of the first contact device and the second contact device are in contact with the conductive connecting device after the corrugated pipe is compressed, and the bottom ends of the first contact device and the second contact device are not in contact with the conductive connecting device when the corrugated pipe is in an extending state.

On the basis of the above scheme and as a preferable scheme of the scheme: one end of the corrugated pipe is closed, the other end of the corrugated pipe is provided with a bead extending out laterally, the buffer box comprises a box body and a box cover, the box body and the box cover are buckled, and the bead is clamped between the box body and the box cover; the box body is provided with an annular groove for installing a sealing ring, and the sealing ring is positioned below the bead; the upper end of the pressure spring is abutted against the buffer box, and the lower end of the pressure spring is abutted against the bottom of the corrugated pipe through the lower cushion; the box is provided with an ink outlet.

On the basis of the above scheme and as a preferable scheme of the scheme: the lower pad is provided with a through hole for the bottom end of the first contact device to pass through; a flow limiting valve is arranged in the ink outlet.

On the basis of the above scheme and as a preferable scheme of the scheme: the first contact device comprises a screw rod and a first contact piece, the screw rod is in threaded connection with the buffer box, the screw rod extends into the inner cavity, a splicing cap is arranged on the screw rod, and one end of the first contact piece is connected with the screw rod.

On the basis of the above scheme and as a preferable scheme of the scheme: the second contact device comprises a second contact piece, one end of the second contact piece is in contact with the corrugated pipe, and the other end of the second contact piece extends out of the buffer box; the conductive connecting device is the corrugated pipe, and the corrugated pipe is made of metal materials or conductive rubber materials.

On the basis of the above scheme and as a preferable scheme of the scheme: the second contact device comprises a second contact piece, the second contact piece is connected with the pressure spring, the conductive connection device comprises the pressure spring and the lower pad, and the lower pad is made of metal materials or is provided with a metal sheet.

On the basis of the above scheme and as a preferable scheme of the scheme: the conductive connecting device is a lower pad, and the lower pad is made of a metal material or a conductive non-metal material.

The invention also provides an ink-jet printer which comprises the hydraulic buffer, wherein the hydraulic buffer is communicated with a pipeline in an ink supply system, and when the first contact device and the second contact device are contacted with the conductive connecting device after the inner cavity space is reduced to form triggering electric connection, the control unit controls the pressure pump to stop working.

On the basis of the above scheme and as a preferable scheme of the scheme:

compared with the prior art, the utility model outstanding and profitable technological effect is:

the hydraulic buffer of the utility model adopts the structure of the corrugated pipe and the pressure spring, when the ink pressure is increased, the corrugated pipe and the pressure spring are contracted to release the medium cavity, and the ink pressure is correspondingly reduced; as the ink pressure decreases, the volume of the media chamber is reduced, thereby eliminating pressure fluctuations. After the medium cavity is filled with the pressure ink, the corrugated pipe does not work under the tension state, so that the hydraulic buffer works more stably and has longer service life.

On the other hand, when the ink pressure in the medium cavity is increased and is influenced by the ink pressure, the pressure spring is compressed, the corrugated pipe is contracted, and the height position of the conductive connecting device relative to the buffer box is raised along with the shortening of the whole length of the conductive connecting device, so that the first contact device and the second contact device are electrically connected through the conductive connecting device. Thus, the hydraulic buffer with the first contact means, the conductive connection means and the second contact means has an ink pressure detection function, and functions as a switch in a circuit for controlling the pressure pump.

Drawings

Fig. 1 is a schematic view of the overall structure of an embodiment of the present invention.

Fig. 2 is a cross-sectional view of an embodiment of the present invention.

Fig. 3 is a cross-sectional view of an embodiment of the present invention.

Fig. 4 is an exploded schematic view of an embodiment of the present invention.

Fig. 5 is a schematic structural diagram of another embodiment of the present invention.

Fig. 6 is a schematic structural diagram of another embodiment of the present invention.

Fig. 7 is a schematic diagram of a pressure pump control of the inkjet printer of the present invention.

Detailed Description

In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments obtained by a person skilled in the art without making any inventive step, based on the given embodiments, fall within the scope of protection of the present application.

In the description of the present application, it is to be understood that the terms "upper", "lower", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

In the description of the present application, the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated.

The utility model provides a hydraulic buffer, the pressure fluctuation can be eliminated on one hand to its one side, and on the other hand hydraulic buffer has the switch function, can use as its overvoltage protection's part in the ink system of ink jet numbering machine.

Example one

As shown in fig. 1 to 4, the present embodiment discloses a hydraulic shock absorber including a buffer tank 1, the buffer tank 1 having a medium chamber 11 and an ink inlet 12, the ink inlet 12 communicating with the medium chamber 11. In the present embodiment, referring to fig. 2, the buffer box 1 includes a box body 101 and a box cover 102, the box body 101 is substantially barrel-shaped, and the box body 101 and the box cover 102 are fastened together. The housing 101 and the cover 102 define the chamber 10.

Bellows 2 which is telescopic and closed at one end. In the present embodiment, the bellows 2 has a corrugated folded wall, and is therefore stretchable in the longitudinal direction thereof. Influenced by the ink pressure, when the ink pressure is increased, the corrugated pipe 2 is contracted, and the whole length is shortened; when the ink pressure decreases, bellows 2 is gradually stretched by spring 3 to recover its length.

As shown in fig. 2, a bellows 2 is connected to the buffer tank 1, and the bellows 2 separates a chamber 10 into a medium chamber 11 and an inner chamber 13. In the present embodiment, one end of the bellows 2 is closed, and the other end of the bellows 2 has a bead 21 projecting laterally, as shown in the drawing, the bead 21 is sandwiched between the case 101 and the case cover 102, the bellows 2 and the buffer case 1 constitute the inner chamber 13, and the lower surface of the bead 21 forms a sealing fit with the case 101, whereby the inner chamber 13 is isolated from the medium chamber 11, i.e., ink does not enter the inner chamber 13.

As shown in the drawings, the case 101 is provided with a recessed cavity 1011, the recessed cavity 1011 being for receiving the bead 21, and an annular groove 1012 being provided on a bottom wall of the recessed cavity 1011, the annular groove 1012 being fitted with a seal ring 1013, thereby improving sealability between the bellows 2 and the case 101.

The hydraulic buffer also comprises a pressure spring 3, and the pressure spring 3 is connected with the corrugated pipe 2. The corrugated pipe 2 and the pressure spring 3 contract along with the increase of the pressure in the medium cavity 11 to reduce the occupied space in the medium cavity 11, and expand along with the decrease of the pressure in the medium cavity 11 to increase the occupied space of the corrugated pipe 2 in the medium cavity 11. When the ink pressure is increased, the corrugated pipe 2 and the pressure spring 3 are contracted to release the medium cavity 11, and the ink pressure is correspondingly reduced; when the ink pressure decreases, the space of the medium chamber 11 is reduced, thereby eliminating the pressure fluctuation, thereby stabilizing the ink pressure.

The hydraulic shock absorber of the present embodiment further includes a first contact device 4, a second contact device 5, and a conductive connection device 60, and the first contact device 4 and the second contact device 5 are fixed to the shock-absorbing housing 1. The first contact device 4 and the second contact device 5 are both in contact with the conductive connection device 60 after the bellows 2 is contracted to form a triggering electrical connection, and the first contact device 4 and the second contact device 5 are disconnected after the bellows 2 is expanded.

In this embodiment, the first contact device 4, the conductive connection device 60 and the second contact device 5 form a switching function, and the ink pressure in the medium chamber 11 triggers the first contact device 4, the conductive connection device 60 and the second contact device 5 to be connected in series to form a passage. It is understood that the first contact device 4, the conductive connecting device 60 and the second contact device 5 form a passage, because the pressure of the ink in the medium chamber 11 is larger, the pressure spring 3 is compressed and the bellows 2 contracts under the influence of the pressure of the ink, and as the whole length of the bellows is shortened, the height position of the conductive connecting device 60 relative to the buffer tank 1 is raised, so that the first contact device 4 and the second contact device 5 are electrically connected through the conductive connecting device 60. Thereby, the hydraulic buffer with the first contact device 4, the conductive connection device 60, and the second contact device 5 has an ink pressure detecting function. In the ink supply system, the hydraulic buffer can be used as a sensor unit and a switch in the pressure pump power supply system.

In the present embodiment, the conductive connecting device 60 is a corrugated tube 2, and the corrugated tube 2 is made of a conductive material, which may be made of a conductive rubber material or a metal material. Preferably, the corrugated pipe 2 is made of a metal material, and the corrugated pipe 2 made of the metal material has better corrosion resistance and longer service life due to the chemical components contained in the ink. Said first contact means 4 is inserted in the inner chamber 13, the bottom end 41 of the first contact means 4 being in contact with the bottom of the bellows 2 after compression of the bellows 2, the bottom end 41 of the first contact means 4 not being in contact with the bottom of the bellows 2 when the bellows 2 is in the extended state, as shown in the state of fig. 2, in which the bottom end 41 of the first contact means 4 forms an open circuit with the bellows 2. Said second contact means 5 is kept in contact with the bellows 2.

Referring to fig. 2, in the present embodiment, the hydraulic shock absorber further includes a lower pad 22, and the lower pad 22 is made of a plastic material. The upper end of the pressure spring is abutted against the buffer tank 1, and the lower end of the pressure spring is abutted against the bottom of the corrugated pipe 2 through the lower cushion 22. As shown in the figure, the under-pad 22 is placed at the bottom of the corrugated tube 2. The lower pad 22 is provided with a through hole 221 through which the bottom end 41 of the first contact means 4 passes. By adopting the structure of the plastic lower pad 22, the pressure spring 3 is abutted, so that the pressure spring 3 indirectly acts on the bottom of the corrugated pipe 2, and the corrugated pipe 2 is effectively protected.

In the above embodiment, the lower pad 22 is made of plastic material, as another equivalent embodiment, the lower pad 22 may also be made of metal material, and a structure without through holes is provided on the lower pad 22, the lower pad 22 made of metal material is abutted by the compression spring 3, and the lower pad 22 is also abutted by the bottom end 41 of the first contact device 4. Thus, the under-pad 22 and the corrugated tube 2 made of the metal material serve as the conductive connection means 60.

Referring to fig. 2, the first contact device 4 includes a screw rod 42 and a first contact piece 43, the screw rod 42 is in threaded connection with the buffer box 1, a splicing cap 44 is arranged on the screw rod 42, and one end of the first contact piece 43 is connected with the screw rod 42. In the present embodiment, the screw rod 42 is screwed with the box cover 102 of the buffer box 1, so that the relative height position of the screw rod 42 and the box cover 102 can be adjusted, and then the screw rod 42 is fixed by the split cap 44. In a specific application, by adjusting the relative height position of the screw rod 42, when the relative height position of the screw rod 42 is low, the first contact device 4 and the second contact device 5 can be triggered to form a passage when the ink pressure value is low, and when the relative height position of the screw rod 42 is high, the first contact device 4 and the second contact device 5 can be triggered to form a passage when the ink pressure value is high. To facilitate the rotation of the screw rod 42 during the adjustment of the height position of the screw rod 42, a notch 421 is provided at the top of the screw rod 42.

The second contact device 5 includes a second contact piece 51, one end of the second contact piece 51 is in contact with the bead 21, and the other end of the second contact piece 51 extends out of the buffer tank 1. As shown in the figure, the bottom end of the second contact piece 51 is bent to fit the bead 21 and sandwiched between the bead 21 and the cover 102, and the cover 102 is provided with a mounting hole 1021 through which the second contact piece 51 extends.

Referring to fig. 3, in the present embodiment, a first joint 61 is fixed to the bottom of the case 101, and the ink inlet 12 is formed by the first joint 61. The bottom of the box 101 is fixed with a second joint 62, an ink outlet is formed by the second joint 62, and a flow limiting valve 63 is arranged in the ink outlet. The flow restriction valve 63 has a tubular structure, which may be made of a quartz glass material, and the inner diameter of the flow restriction valve 63 is smaller than the inner diameter of the first joint 61. Typically, the internal diameter of the constrictor valve 63 is 0.5 millimeters. In a specific application, ink enters the medium chamber 11 from the ink inlet 12 and flows out from the ink outlet. After the whole medium cavity 11 is filled with ink, the external pressure pump continuously works, so that more ink enters the medium cavity 11, and the medium cavity is easily filled with ink under the influence of the flow. The ink flowing out of the ink outlet carries pressure.

In this embodiment, the first contact device 4, the conductive connecting device 60 and the second contact device 5 are connected in series to form a via. The conductive connecting device is a corrugated pipe, and as another embodiment of the conductive connecting device, the conductive connecting device comprises the pressure spring and the lower pad, and the lower pad is made of a metal material or a metal sheet is arranged on the lower pad. Therefore, the first contact device, the pressure spring, the lower pad and the second contact device are connected in series to form a passage.

Example two

Referring to fig. 5, the hydraulic shock absorber of the present embodiment is substantially the same as the hydraulic shock absorber of the first embodiment, and the difference therebetween is that: the first contact device 4 and the second contact device 5 are arranged differently. Specifically, in the present embodiment, each of the first contact device 4 and the second contact device 5 includes a screw rod 42, the screw rod 42 is screwed with the box cover 102, and the split caps 44 are screwed on the screw rod 42. The split caps 44 are adapted to be tightened onto the cover 102 to secure the lead screw 42 relative to the cover 102. The lower pad 22 is correspondingly provided with a through hole 221 for the bottom end of the lead screw 42 to pass through, thereby the bottom end of the lead screw is electrically connected with the bottom of the metal corrugated pipe 2 in a triggering manner. In a specific application, after the pressure of the ink in the medium chamber 11 is increased to a certain level, the bottom ends of the two lead screws 42 are both in contact with the bottom of the bellows 2 to form a passage.

In this embodiment, an elastic lug may be provided at the bottom end of the screw rod 42, which is retractable in the axial direction, so that both the first contact device 4 and the second contact device 5 can effectively contact the bottom of the metal bellows 2. Through the structure of the elastic binding post, the requirement on the consistency of the heights of the two screw rods 42 is reduced.

EXAMPLE III

The hydraulic shock absorber of the present embodiment is substantially the same as the hydraulic shock absorbers of the first and second embodiments, and the difference between the hydraulic shock absorbers is that: the conductive connection device has a different structure, in this embodiment, the conductive connection device is a lower pad 22, which is made of a conductive rubber material or a metal material, or is mainly made of a plastic material, a metal sheet 221 is disposed on the top of the conductive connection device, and the first contact device 4 and the second contact device 5 are both in contact with the lower pad 22 after the bellows 2 is contracted to form a triggering electrical connection.

As shown in fig. 6, in this embodiment, the first contacting device may use an elastic post 41, the second contacting device 5 may also use an elastic post 41, and the lower pad 22 has a conductive bracket 220 thereon, so as to compensate for the shorter elastic post. Preferably, the under-pad 22 is mainly made of plastic material, on top of which a metal sheet 221 is arranged for triggerably connecting the first contact means 4 and the second contact means 5.

It should be noted that in the hydraulic shock absorber, it is preferable to use the first contact device 4 and the second contact device 5 with the lead screw 42, whereby the ink pressure value for triggering the electrical connection can be adjusted, which is an advantage not possessed by other structures.

In the above embodiment, the lead screw 42 may also be replaced by another conductive column structure, and is fixedly connected with the buffer tank 1 by being fixed or injection-molded on the tank cover 102.

In the above embodiment, the corrugated tube may be replaced by a cup-shaped isolation film, and in order to meet the requirement of conductivity as a conductive connection device, the material of the corrugated tube may also be a conductive rubber material.

The utility model discloses an ink jet numbering machine, including above-mentioned hydraulic buffer, the pipeline in hydraulic buffer and the ink supply system is linked together, works as when hydraulic buffer's first contact device and second contact device form the electricity of trigger nature and connect, the stop work of control unit 200 control force pump 300. In this embodiment, the hydraulic buffer device is used as a sensor for detecting the pressure of the ink, and when there is a foreign object in the ink or a blockage is generated in other places in the ink supply system, the ink may not flow smoothly. At the moment, ink continuously enters from the ink inlet of the hydraulic buffer, the spring and the metal corrugated pipe are stressed and compressed, when the spring and the corrugated pipe contract to a certain degree, the corrugated pipe can touch the bottom end of the screw rod, so that the first contact device and the second contact device form a passage, the controller receives a signal and judges that the pressure is too high, the pressure pump is controlled to stop working, and the damage to parts caused by continuous pressure supply of the pressure pump is avoided. And after the pressure in the hydraulic buffer flows out and the corrugated pipe is disconnected from the screw rod, the control unit controls the pressure pump to work.

The above-mentioned embodiment is only the preferred embodiment of the present invention, and does not limit the protection scope of the present invention according to this, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. The utility model provides a hydraulic buffer, includes the surge tank, the surge tank has cavity and ink inlet, and ink inlet and cavity are linked together, its characterized in that: the isolation device is connected with the buffer box and isolates the cavity into a medium cavity and an inner cavity, a pressure spring is arranged in the inner cavity, the upper end of the pressure spring abuts against the buffer box, and the lower end of the pressure spring abuts against the bottom of the isolation device; the first contact device and the second contact device are fixed with the buffer box, the first contact device and the second contact device are in contact with the conductive connection device after the inner cavity space is reduced to form triggered electric connection, and the first contact device and the second contact device are disconnected from the electric connection after the inner cavity space is enlarged.

2. A hydraulic shock absorber according to claim 1, wherein the isolation means is a bellows, the first contact means is inserted into the inner chamber, a bottom end of the first contact means contacts the conductive connection means after compression of the bellows, the bottom end of the first contact means does not contact the conductive connection means when the bellows is in the expanded state, and the second contact means is held in contact with the conductive connection means.

3. The hydraulic shock absorber according to claim 1, wherein the isolation means is a bellows, the first and second contact means are inserted into the inner chamber, the bottom ends of the first and second contact means are in contact with the conductive connecting means after the bellows is compressed, and the bottom ends of the first and second contact means are not in contact with the conductive connecting means when the bellows is in the expanded state.

4. A hydraulic damper according to claim 2 or 3, wherein: one end of the corrugated pipe is closed, the other end of the corrugated pipe is provided with a bead extending out laterally, the buffer box comprises a box body and a box cover, the box body and the box cover are buckled, and the bead is clamped between the box body and the box cover; the box body is provided with an annular groove for installing a sealing ring, and the sealing ring is positioned below the bead; the upper end of the pressure spring is abutted against the buffer box, and the lower end of the pressure spring is abutted against the bottom of the corrugated pipe through the lower cushion; the box is provided with an ink outlet.

5. A hydraulic damper according to claim 4, wherein: the lower pad is provided with a through hole for the bottom end of the first contact device to pass through; a flow limiting valve is arranged in the ink outlet.

6. A hydraulic damper according to claim 2 or 3, characterized in that: the first contact device comprises a screw rod and a first contact piece, the screw rod is in threaded connection with the buffer box, the screw rod extends into the inner cavity, a splicing cap is arranged on the screw rod, and one end of the first contact piece is connected with the screw rod.

7. A hydraulic damper according to claim 2, wherein: the second contact device comprises a second contact piece, one end of the second contact piece is in contact with the corrugated pipe, and the other end of the second contact piece extends out of the buffer box; the conductive connecting device is the corrugated pipe, and the corrugated pipe is made of metal materials or conductive rubber materials.

8. The hydraulic damper according to claim 4, wherein: the second contact device comprises a second contact piece, the second contact piece is connected with the pressure spring, the conductive connection device comprises the pressure spring and the lower pad, and the lower pad is made of metal materials or is provided with a metal sheet.

9. A hydraulic damper according to claim 3, wherein: the conductive connecting device is a lower pad, and the lower pad is made of a metal material or a conductive non-metal material.

10. An ink jet numbering machine, its characterized in that: the inkjet printer comprises the hydraulic buffer as claimed in any one of claims 1 to 9, the hydraulic buffer is communicated with a pipeline in an ink supply system, and when the first contact device and the second contact device are both in contact with the conductive connecting device after the inner cavity space is reduced to form triggering electric connection, the control unit controls the pressure pump to stop working.