Needle valve type air cylinder structure with cooling function

Abstract

The utility model relates to the technical field of hot runners, and particularly discloses a needle valve type air cylinder structure with a cooling function. The cylinder body, the cylinder cover and the base form an inner cavity of the cylinder, the piston is arranged in the cylinder and divides the inner cavity into an upper cavity and a lower cavity, the lower portion of the piston is connected with a needle valve which is coaxially arranged, the lower end of the needle valve penetrates out of the base and extends out of the cylinder, an upper air channel and a lower air channel are arranged on the outer side of the cylinder, the upper air channel is communicated with the upper cavity, and the lower air channel is communicated with the lower cavity. A mounting cavity for mounting and fixing the needle valve and a mounting piece are arranged in the piston, a ventilation gap is reserved between the mounting cavity and the needle valve, the piston is provided with a first cooling air channel for communicating the lower cavity with the mounting cavity, and the base is provided with a second cooling air channel for communicating the mounting cavity with the lower air channel. The air cylinder structure can reduce the temperature of the needle valve, reduce the expansion amount of the needle valve and reduce the risk of abrasion of an inner hole of the valve sleeve.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of hot runner, specifically disclose a needle valve type with cooling cylinder structure. BACKGROUND

[0002] At present, the traditional injection hot runner cylinder, such as Figure 1 As shown in the structure design, the piston separates the cylinder cavity into two chambers, the upper air passage is communicated with the upper chamber, and the lower air passage is communicated with the lower chamber. Its working principle is that the air pressure difference is generated by the upper and lower air communication of the cylinder, so as to drive the piston to move up and down in the cylinder, and the piston drives the needle valve to move up and down. In the application scene of the traditional hot runner cylinder, the valve sleeve is fixed on the distribution plate, the needle valve passes through the valve sleeve, and then is accurately inserted into the distribution plate. The up and down movement of the needle valve following the piston skillfully controls the extrusion of the rubber material, and realizes the accurate regulation and control of the rubber material flow in the injection process.

[0003] However, the existing cylinder structure has the following disadvantages: in order to prevent the rubber material of the distribution plate from seeping out from the gap between the valve sleeve and the needle valve, the cooperation gap between the needle valve and the valve sleeve is small, and the gap is generally about 0.003mm. When the valve sleeve and the needle valve are heat expanded at high temperature, the needle valve pad block is in contact with the mold plate due to the heat dissipation of the needle valve pad block around the valve sleeve, the heat of the distribution plate around the valve sleeve is guided into the mold plate by the needle valve pad block, the local temperature of the distribution plate is reduced, and then the temperature of the valve sleeve is reduced. However, the existing needle valve does not have a corresponding cooling way, so that the heat expansion amount of the needle valve is greater than the heat expansion amount of the inner hole of the valve sleeve, the hole of the valve sleeve is easily worn, and the operation efficiency of the cylinder is also affected. UTILITY MODEL CONTENTS

[0004] The utility model aims at overcoming the insufficient of prior art, provides a needle valve type with cooling cylinder structure.

[0005] The utility model discloses a needle valve type with cooling cylinder structure adopts the following technical scheme:

[0006] A needle valve type with cooling cylinder structure, including the cylinder body that constitutes the cylinder cavity, cylinder cover and base, and the piston that sets up in the cylinder and divides the inner chamber into upper chamber and lower chamber, the lower part of piston is connected with the coaxial needle valve, the needle valve lower end passes through the base and extends to the outside of cylinder, the outside of cylinder is equipped with upper air passage and lower air passage, the upper air passage is communicated with the upper chamber, the piston is equipped with the installation cavity and installation part for the needle valve installation fixed, the installation cavity and needle valve have the air gap, the piston is equipped with the first cooling air channel that communicates the lower chamber with the installation cavity, and the base is equipped with the second cooling air channel that communicates the installation cavity with the lower air passage.

[0007] Preferably, the piston is provided with a through hole, one end of the through hole extends and communicates to the lower chamber, and the other end extends and communicates to the installation cavity.

[0008] Preferably, a plurality of said through holes are circumferentially equidistantly arranged on said piston.

[0009] Preferably, a first annular gap is left between the outer sidewall of said mounting member and the inner sidewall of said mounting cavity, and a first through slot is arranged on the bottom surface of said mounting member, one end of said first through slot extending to said first annular gap, and the other end extending to said air passage gap.

[0010] Preferably, a plurality of said first through slots are circumferentially equidistantly arranged on said mounting member.

[0011] Preferably, a guiding hole is arranged on said base for guiding the up-and-down movement of said piston, and a second through slot is arranged on the bottom surface of said base, one end of said second through slot extending to said guiding hole, and the other end extending to said lower air passage.

[0012] Preferably, a plurality of said second through slots are circumferentially equidistantly arranged on said base.

[0013] Preferably, a support ring is arranged below said base, the top end of said support ring abutting against the bottom end of said base, and a second annular gap is left between the inner sidewall of said support ring and the outer sidewall of said piston.

[0014] Preferably, a rubber ring is arranged on the lower end of said support ring, and said needle valve extends out of said rubber ring and into the outside of said air cylinder.

[0015] Preferably, an inner snap spring is arranged in said cylinder body, the outer ring of said inner snap spring being clamped to the inner wall of said cylinder body, and the inner ring of said inner snap spring extending into the inner cavity of said air cylinder and leaving a deformation gap with the top surface of said base.

[0016] Compared with the prior art, the utility model at least has the following beneficial effects:

[0017] The utility model discloses a mounting cavity and a mounting member for mounting and fixing the needle valve are arranged in the piston, the mounting cavity and the needle valve leave an air passage gap, a first cooling air passage is arranged on the piston to communicate the lower cavity with the mounting cavity, a second cooling air passage is arranged on the base to communicate the mounting cavity with the lower air passage, when the gas in the lower air passage of the air cylinder enters the lower cavity, part of the airflow enters the mounting cavity from the first cooling air passage of the piston, and then passes through the second cooling air passage to flow to the lower cavity, the moving airflow contacts the needle valve in the air passage gap of the mounting cavity, and heat dissipation is generated, thereby reducing the temperature of the needle valve, reducing the expansion amount of the needle valve and reducing the risk of wear of the inner hole of the valve sleeve. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic view of the air cylinder structure of the prior art;

[0019] Figure 2Fig. 1 is a schematic view of the overall structure of a needle valve type cylinder structure with cooling according to the present embodiment;

[0020] Figure 3 Fig. 2 is a partial enlarged view of the needle valve type cylinder structure with cooling according to the present embodiment; Figure 2

[0021] Figure 4 Fig. 3 is a schematic view of the cooling air passage of the needle valve type cylinder structure with cooling according to the present embodiment;

[0022] Figure 5 Fig. 4 is a schematic view of the piston structure of the needle valve type cylinder structure with cooling according to the present embodiment;

[0023] Figure 6 Fig. 5 is a schematic view of the mounting member structure of the needle valve type cylinder structure with cooling according to the present embodiment;

[0024] Figure 7 Fig. 6 is a schematic view of the base structure of the needle valve type cylinder structure with cooling according to the present embodiment.

[0025] BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 1. template; 2. flow distribution plate; 3. cylinder body; 4. base; 41. guide hole; 42. second through slot; 43. third annular gap; 5. needle valve; 6. valve sleeve; 7. needle valve pad; 8. piston; 81. mounting cavity; 811. air passage gap; 812. first annular gap; 813. second annular gap; 82. through hole; 9. upper air passage; 10. lower air passage; 11. gate; 12. mounting member; 121. first through slot; 13. support ring; 14. rubber ring; 15. inner circlip. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0028] The present embodiment discloses a needle valve type cylinder structure with cooling, referring to Figures 2-7 ​The cylinder is fixed in the template 1, which includes the cylinder body 3 constituting the inner cavity of the cylinder, the cylinder cover and base 4, and the piston 8 arranged in the cylinder to divide the inner cavity into the upper cavity and the lower cavity, the lower part of the piston 8 is connected with the coaxially arranged needle valve 5, the lower end of the needle valve 5 penetrates through the base 4 and extends to the outside of the cylinder, the upper gas channel 9 and the lower gas channel 10 are arranged outside the cylinder, the upper gas channel 9 is communicated with the upper cavity, in order to enable the lower gas channel 10 to flow the gas with lower temperature to contact the needle valve 5 so as to achieve the purpose of cooling the needle valve 5, the piston 8 is provided with the mounting cavity 81 for mounting and fixing the needle valve 5 and the mounting part 12, the mounting cavity 81 is provided with the air gap 811 with the needle valve 5, the piston 8 is provided with the first cooling gas channel communicated with the lower cavity and the mounting cavity 81, the base 4 is provided with the second cooling gas channel communicated with the mounting cavity 81 and the lower gas channel, in this way, when the gas in the lower gas channel of the cylinder enters the lower cavity, part of the gas flow enters the mounting cavity 81 from the first cooling gas channel of the piston 8 and then flows to the lower cavity through the second cooling gas channel, the moving gas flow contacts the needle valve 5 in the air gap 811 of the mounting cavity 81, air flow heat dissipation is generated, the temperature of the needle valve 5 is reduced, the expansion amount of the needle valve 5 is reduced, and the risk of wear of the inner hole of the valve sleeve 6 is reduced.

[0029] In combination Figures 3-5 , the through hole 82 is arranged on the piston 8 as at least part of the first cooling gas channel, one end of the through hole 82 extends outwardly and is communicated with the lower cavity, the other end extends outwardly and inwardly and is communicated with the mounting cavity 81, so as to communicate the lower cavity with the mounting cavity 81. As a preferred solution, a plurality of through holes 82 are arranged at a circumferential equidistant interval on the piston 8, which can balance the impact of the gas flow and uniformly dissipate heat.

[0030] In combination Figures 3-4 and Figure 6 , the outer side wall of the mounting part 12 is provided with the first annular gap 812 with the inner side wall of the mounting cavity 82, the bottom surface of the mounting part 12 is provided with the first through groove 121, one end of the first through groove 121 extends outwardly and is communicated with the first annular gap 812, the other end extends inwardly and is communicated with the air gap 811, after the gas flow enters the mounting cavity 81 from the through hole 82, it sequentially passes through the first annular gap 812, the first through groove 121 and the air gap 811, so as to contact and dissipate heat with the needle valve 5. As a preferred solution, a plurality of first through grooves 121 are arranged at a circumferential equidistant interval on the mounting part 12, which can uniformly ventilate and accelerate heat dissipation. Of course, in other embodiments, the mounting part 12 can also be other hollow structures with ventilation, and the mounting part shown in the embodiment has a better structural strength.

[0031] In combination Figures 3-4 and Figure 7The second through groove 42 of the base 4 is communicated with the guide hole 41 and the lower air channel 10. The air flow entering the installation cavity 81 passes through the air gap 811 and contacts the needle valve 5 to dissipate heat, and then flows out from the bottom of the piston to the outside of the piston, and then flows into the second through groove 42 and then flows into the lower air channel 10. As a preferred solution, the second through groove 42 is provided with a plurality of second through grooves 42 which are arranged at equal intervals in the circumferential direction of the base 4, and the plurality of second through grooves 42 play a role in uniform air passage and accelerated heat dissipation.

[0032] As a preferred solution, referring to Figures 3-4 The base 4 is provided with a support ring 13, the top end of the support ring 13 abuts against the bottom end of the base 4, the support ring 13 plays a role in reinforcing the base 4 and supporting stability, and the inner side wall of the support ring 13 and the outer side wall of the piston 8 are provided with a second annular gap 813. In addition, the outer side wall of the base 4 and the mold plate 1 are provided with a third annular gap 43. The air flow entering the installation cavity 81 passes through the air gap 811, flows out from the bottom of the piston to the second annular gap 813, then flows through the second through groove 42 to the third annular gap 43, and finally flows out to the lower air channel 10 to dissipate heat.

[0033] As a preferred solution, referring to Figure 3 The cylinder is provided with an inner snap spring 15, the outer ring of the inner snap spring 15 is clamped on the inner wall of the cylinder, and the inner ring of the inner snap spring 15 extends into the inner cavity of the cylinder and is provided with a deformation gap with the top surface of the base 4. By designing the inner snap spring 15 at the lower end position of the cylinder, when the piston 8 drives the needle valve 5 to move, the needle valve 5 seals the gate 11 for an instant (or about 0.05 mm away from the gate 11), the piston 8 just contacts the inner snap spring 15, and the inner snap spring 15 offsets part of the impact force to reduce the risk of damage to the gate 11. In addition, the lower end of the support ring 13 is provided with a rubber ring 14, the needle valve 5 extends out of the rubber ring 14 and extends to the outside of the cylinder, and the rubber ring 14 also plays a role in buffering when the piston 8 hits.

[0034] The above describes the technical solutions provided by the utility model in detail, and the principles and implementation manners of the utility model are described by applying specific examples; the above description of the embodiments is only used to help understand the method and core idea of the utility model; meanwhile, for those skilled in the art, the specific implementation manners and application range can be changed according to the idea of the utility model, and the above description of the specification should not be understood as a limitation on the utility model.

Claims

1. A needle valve type cylinder structure with cooling, comprising a cylinder body, a cylinder head, and a base forming the cylinder cavity, and a piston disposed within the cylinder to divide the cavity into an upper cavity and a lower cavity, wherein a needle valve is coaxially connected to the lower part of the piston, the lower end of the needle valve extends through the base and out of the cylinder, and an upper air passage and a lower air passage are provided on the outer side of the cylinder, the upper air passage communicating with the upper cavity, characterized in that, The piston is provided with a mounting cavity for mounting the needle valve and a mounting member, the mounting cavity is provided with a ventilation gap with the needle valve, the piston is provided with a first cooling gas channel for connecting the lower cavity and the mounting cavity, and the base is provided with a second cooling gas channel for connecting the mounting cavity and the lower gas channel.

2. The needle-valve type cooled cylinder structure according to claim 1, characterized by The piston is provided with a through hole, one end of the through hole is connected to the lower cavity, and the other end is connected to the mounting cavity.

3. The needle-valve type belt-cooled cylinder structure according to claim 2, characterized by The through hole is provided with a plurality of through holes, and the plurality of through holes are equidistantly arranged circumferentially.

4. The needle-valve type air cylinder structure with cooling according to claim 1, characterized by The outer wall of the mounting member is provided with a first annular gap with the inner wall of the mounting cavity, the bottom surface of the mounting member is provided with a first through slot, one end of the first through slot is connected to the first annular gap, and the other end is connected to the ventilation gap.

5. The needle-valve type belt-cooled cylinder structure according to claim 4, characterized by The first through slot is provided with a plurality of first through slots, and the plurality of first through slots are equidistantly arranged circumferentially.

6. The needle-valve type air cylinder structure with cooling according to claim 1, characterized by The base is provided with a guide hole for guiding the up-and-down movement of the piston, and the bottom surface of the base is provided with a second through slot, one end of the second through slot is connected to the guide hole, and the other end is connected to the lower gas channel.

7. The needle-valve type belt-cooled cylinder structure according to claim 6, characterized by The second through slot is provided with a plurality of second through slots, and the plurality of second through slots are equidistantly arranged circumferentially.

8. The needle-valve type belt-cooled cylinder structure according to claim 6, characterized by The base is provided with a support ring, the top end of the support ring abuts against the bottom end of the base, and the inner wall of the support ring is provided with a second annular gap with the outer wall of the piston.

9. The needle-valve type belt-cooled cylinder structure according to claim 8, characterized by The lower end of the support ring is provided with a rubber ring, the needle valve passes through the rubber ring and extends to the outside of the cylinder.

10. The needle-valve type cooled cylinder structure according to any one of claims 1 to 9, characterized by The cylinder is provided with an inner snap spring, the outer ring of the inner snap spring is clamped on the inner wall of the cylinder, the inner ring of the inner snap spring extends into the inner cavity of the cylinder and is provided with a deformation gap with the top surface of the base.

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