Self-priming spiral pressurized pre-filled bone cement injector

Abstract

The utility model discloses a self-priming spiral pressurized pre-filled bone cement injector, comprising: a barrel, one end of the barrel is a discharge end, the other end of the barrel is an open end, a Luer adapter is arranged on the discharge end, a filter membrane is arranged in the Luer adapter, a nut is threadedly connected on the open end, an internal screw hole is arranged on the nut, a T-shaped sealing ring is sealed in the barrel, the T-shaped sealing ring is connected to the nut, an internal thread is arranged in the T-shaped sealing ring, a piston is movably sealed in the barrel, a quantitative piston rod is connected to the piston, a threaded section is arranged on the quantitative piston rod, the quantitative piston rod is sealed and fitted with the T-shaped sealing ring, an airway is opened between the quantitative piston rod and the threaded section, a detachable plug is sealed on the airway, and a vent hole is opened on the quantitative piston rod. The utility model can accurately control the absorption amount of bone cement monomer, and the bone cement can be directly injected after mixing in the barrel, thereby improving the safety factor.

Description

Technical Field

[0001] The utility model relates to the technical field of medical instruments, in particular to a self-priming spiral pressurized pre-filled bone cement injector. Background Art

[0002] Bone cement is a medical material used in orthopedic surgery. It is composed of liquid monomers and powders. After the two are mixed in a certain proportion, they can be injected into the patient's affected area in a fluid state for solidification. At present, bone cement on the market is generally mixed in a blender first, and then the mixed bone cement is filled into a syringe, and finally injected with a syringe. In this process, the bone cement will be exposed to the external environment, which will not only increase the risk of bone cement contamination, but also bone cement is prone to solidification in the process, reducing the treatment effect. In order to solve the above problems, there are bone cement syringes that integrate stirring and injection on the market, but either the structure is complex and inconvenient to use, or the absorption of the monomer cannot be controlled, because the powder needs to be filled in first and then the monomer during pre-filling. At present, the absorption of the monomer is observed by the scale on the barrel, but with the interference of the powder, the absorption of the monomer cannot be accurately controlled, which will cause the mixed bone cement to be either too thin and poor in solidification performance, or too dry and solidify too quickly. Utility Model Content

[0003] The utility model aims to provide a self-priming spiral pressurized pre-filled bone cement injector which can accurately control the monomer absorption amount when pre-filling powder.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a self-priming spiral pressurized pre-filled bone cement injector, comprising: a barrel, one end of the barrel is a discharge end, and the other end of the barrel is an open end, a Luer adapter is arranged on the discharge end, a filter membrane is arranged in the Luer adapter, a nut is threadedly connected to the open end, an internal screw hole is arranged on the nut, a T-shaped sealing ring is sealed in the barrel, the T-shaped sealing ring is connected to the nut, an internal thread with the same rotation direction as the internal screw hole is arranged in the T-shaped sealing ring, a piston is movably and sealingly arranged in the barrel, a quantitative piston rod is connected to the piston, a threaded section is arranged on the quantitative piston rod, the quantitative piston rod is sealed and fitted with the T-shaped sealing ring, an airway is opened between the quantitative piston rod and the threaded section, a detachable plug is sealed on the airway, and a vent connected to the airway is opened on the quantitative piston rod.

[0005] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, the threaded section is a plastic blind tube with an external thread, a reducing section is provided above the quantitative piston rod, an annular boss is formed between the reducing section and the quantitative piston rod, the plastic blind tube is sleeved and adhered to the reducing section, the plastic blind tube rests on the annular boss, and the airway passes through the quantitative piston rod and the plastic blind tube.

[0006] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, the thread rotation direction between the nut and the barrel is consistent with the thread rotation direction between the nut and the external thread of the plastic blind tube.

[0007] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, the vent hole is arranged at the connection between the quantitative piston rod and the piston.

[0008] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, an annular handle is provided on the plastic blind tube, and a pressure plate is provided on the top of the annular handle.

[0009] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, two arc-shaped handles are symmetrically arranged on the side wall of the barrel.

[0010] Furthermore, the aforementioned self-priming spiral pressurized pre-filled bone cement injector, wherein a filter chamber is arranged on the Luer adapter, a filter membrane is laid in the filter chamber, a first O-ring is arranged on the side wall of the filter chamber, a Luer connector is arranged on the discharge end, the Luer adapter is threadedly connected to the Luer connector, the Luer connector is inserted into the filter chamber and abuts against the filter membrane, and the Luer connector is sealed and fitted with the first O-ring in the filter chamber.

[0011] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, a sealing rubber sleeve is clamped on the piston, an expansion gap is left between the piston and the sealing rubber sleeve, the outer wall of the sealing rubber sleeve is sealingly fitted on the inner wall of the cylinder, and two annular grooves are arranged on the outer wall of the sealing rubber sleeve at intervals.

[0012] Furthermore, in the aforementioned self-priming spiral pressurized pre-filled bone cement injector, a second O-ring is provided on the outer side wall of the open end, and the nut is sealingly fitted with the second O-ring.

[0013] The utility model has the advantages that the length of the quantitative piston rod is determined according to the inner cavity radius of the cylinder and the monomer demand, and then the movement stroke of the piston can be determined by the length of the quantitative piston rod, and the demand for bone cement monomer can be known by the movement stroke of the piston and the radius of the inner cavity of the cylinder. When in use, it is only necessary to pull the piston to the top and abut against the nut, and then use a plug to block the airway, and push the quantitative piston rod downward. The bone cement powder in the cylinder will not be sprayed out of the cylinder under the obstruction of the filter membrane. When the threaded section on the quantitative piston rod contacts the nut, the quantitative piston rod is loosened, and the piston will automatically reset under the action of negative pressure. After the reset is completed, the quantitative piston rod will be A certain amount of bone cement monomer is sucked into the cylinder, so that the absorption amount of bone cement monomer can be accurately controlled; shaking the cylinder can make the bone cement powder and bone cement monomer mix in the cylinder, and the bone cement can be directly injected after mixing in the cylinder, reducing the risk of being contaminated and solidified by exposure to the external environment; when injecting, just remove the plug from the airway, and you can quickly inject by pushing the quantitative piston rod. During the injection process, when the external thread on the plastic blind tube is connected with the internal thread hole on the nut and the internal thread on the T-ring, the resistance encountered in the later injection process can be overcome by screwing and pushing, and the injection work can be easily completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional structural schematic diagram of the self-priming spiral pressurized pre-filled bone cement injector described in the utility model.

[0015] Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure. DETAILED DESCRIPTION

[0016] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and preferred embodiments.

[0017] like Figure 1 , Figure 2As shown, the self-priming spiral pressurized pre-filled bone cement injector described in the utility model comprises: a barrel 1, two arc-shaped grips 11 are symmetrically arranged on the side wall of the barrel 1, which are convenient for the staff to hold during injection, one end of the barrel 1 is a discharge end, and a Luer connector 12 is arranged on the discharge end, which can be conveniently connected to an injection nozzle or an extension tube through the Luer connector 12, so as to facilitate the injection of bone cement into the patient's affected part, a Luer adapter 121 is threadedly connected to the Luer connector 12, a filter cavity is arranged on the Luer adapter 121, and a filter membrane 122 is laid in the filter cavity, and the function of the filter membrane 122 is to block bone cement powder and To allow air and bone cement monomers to pass through, a first O-ring 123 is arranged on the side wall of the filter chamber, the Luer connector 12 is inserted into the filter chamber and abuts against the filter membrane 122, the Luer connector 12 is sealed and fitted with the first O-ring 123 in the filter chamber, when bone cement powder is pre-installed in the cylinder 1, after the Luer adapter 121 is threadedly connected to the Luer connector 12, the first O-ring 123 in the Luer adapter 121 plays a sealing role, and the filter membrane 122 in the Luer adapter 121 can prevent the bone cement powder in the cylinder 1 from falling out, but the filter membrane 122 will not hinder the bone cement monomer from entering the cylinder 1.

[0018] The other end of the cylinder 1 is an open end, a nut 2 is threadedly connected to the open end, a second O-ring 13 is arranged on the outer wall of the open end, the nut 2 is sealed with the second O-ring 13, an inner screw hole is arranged on the nut 2, a T-ring 14 is sealed in the cylinder 1, the T-ring 14 is inserted into and adhered to the nut 2, an inner thread with the same rotation direction as the inner screw hole is arranged on the inner hole of the T-ring 14, a piston 3 is movably arranged in the cylinder 1, and a sealing The rubber sleeve 4 has an expansion gap between the piston 3 and the sealing rubber sleeve 4. The outer wall of the sealing rubber sleeve 4 is sealed against the inner wall of the cylinder 1. Two annular grooves are arranged on the outer wall of the sealing rubber sleeve 4 at intervals. A large amount of heat is released during the curing or mixing process of bone cement. The sealing rubber sleeve 4 expands after being heated. The expansion gap is left between the piston 3 and the sealing rubber sleeve 4 and the annular groove is arranged on the outer wall of the sealing rubber sleeve 4 to prevent the sealing rubber sleeve 4 from getting stuck with the cylinder 1 after being heated and expanded.

[0019] A quantitative piston rod 31 is connected to the piston 3. The quantitative piston rod 31 is sealed with the T-shaped sealing ring 14. A threaded section is arranged on the quantitative piston rod 31. The threaded section is a plastic blind tube 32 with an external thread. The thread rotation direction between the external thread and the internal thread hole of the plastic blind tube 32 is consistent with the thread rotation direction between the nut 2 and the cylinder 1. A reduced diameter section 311 is arranged above the quantitative piston rod 31. An annular boss is formed between the reduced diameter section 311 and the quantitative piston rod 31. The plastic blind tube 32 is sleeved and adhered to the reduced diameter section 311. The plastic blind tube 32 rests on the annular boss. An airway 33 is arranged between the plastic blind tube 32, and a detachable plug 5 is sealed on the airway 33, and the plug 5 is sealed on the plastic blind tube 32. A vent 34 connected to the airway 33 is opened at the connection between the quantitative piston rod 31 and the piston 3, and an annular handle 321 is arranged on the plastic blind tube 32. Holding the annular handle 321 can facilitate the rotation of the quantitative piston rod 31. A pressure plate 322 is arranged on the top of the annular handle 321. The pressure plate 322 can increase the contact area. When pushing the quantitative piston rod 31, the staff's palm can be pressed against the pressure plate 322 to better apply the pushing force.

[0020] The length of the quantitative piston rod 31 is determined by the inner cavity radius of the cylinder 1 and the monomer demand. The bone cement monomer demand is the volume of the bone cement monomer. According to the volume of the bone cement monomer, the volume required by the cylinder 1 when carrying the bone cement monomer can be known. The height value required by the cylinder 1 when carrying the corresponding volume of bone cement monomer can be calculated through the volume of the cylinder 1 and the inner cavity radius of the cylinder 1. This height value is the length of the quantitative piston rod 31.

[0021] When a preset volume of bone cement monomer needs to be absorbed, the length of the quantitative piston rod 31 can be determined according to the preset volume of bone cement monomer and the inner cavity radius of the cylinder 1. When in use, the piston 3 is first pulled upward by the quantitative piston rod 31. As the piston 3 moves upward, the air between the piston 3 and the nut 2 is discharged through the vent 34 and the airway 33. When the piston 3 abuts against the T-shaped sealing ring 14, the T-shaped sealing ring 14 blocks the vent 34, and then a plug 5 is blocked on the airway 33. At this time, the quantitative piston rod 31 is pushed downward. Since the quantitative piston rod 31 slides downward in a sealed manner between the T-shaped sealing ring 14, and the airway 33 is blocked, a negative pressure is present in the cylinder 1 between the piston 3 and the nut 2, and the downward movement of the piston 3 is to adjust the inner cavity volume of the cylinder 1. During the compression process, when the external thread on the plastic blind tube 32 on the quantitative piston rod 31 contacts the internal thread hole on the nut 2, it means that the quantitative piston rod 31 drives the piston 3 to move downward into place. At this time, the compressed amount of the inner cavity volume of the cylinder 1 is equal to the volume of the bone cement monomer that needs to be absorbed. The quantitative piston rod 31 is released, and the piston 3 will automatically move upward and reset with the quantitative piston rod 31 under the action of the negative pressure between the piston 3 and the nut 2. The piston 3 can release the compressed inner cavity when moving upward. When releasing the compressed inner cavity, negative pressure will be generated in the cylinder 1 below the piston 3, and the bone cement monomer can be absorbed by the negative pressure. After the piston 3 is completely reset, the volume of the bone cement monomer absorbed by the piston 3 is the released compressed inner cavity volume, that is, the preset bone cement monomer volume.

[0022] During production, a Luer adapter 121 with a filter membrane 122 is threadedly connected to the Luer connector 12 of the barrel 1, and then the nut 2 is opened, and a quantitative amount of bone cement powder is poured into the barrel 1, and then the piston 3 connected to the quantitative piston rod 31 is extended into the barrel 1, and the nut 2 is screwed on the barrel 1, and then the quantitative piston rod 31 is pulled upward, the piston 3 is pressed against the nut 2, and the airway 33 is blocked with the plug 5, and a protective cover is put on the Luer adapter 121. In this way, the produced stirring syringe can be packaged and transported. When in use, remove the protective cover on the Luer adapter 121, thread the pipette on the Luer adapter 121, place the pipette in the ampoule containing the bone cement monomer, and then place the end of the cylinder 1 with the Luer adapter 121 facing upward or horizontally to prevent the bone cement powder in the cylinder 1 from being blocked on the filter membrane 122, push the quantitative piston rod 31 with force, and the piston 3 will discharge the air in the cylinder 1 to the outside, and a small amount of bone cement powder in the cylinder 1 will be affected by the air flow and flow with the air. When the piston 31 is moved together, the filter membrane 122 in the Luer adapter 121 can block the bone cement powder in the cylinder 1. When the plastic blind tube 32 on the quantitative piston rod 31 contacts the nut 2, the quantitative piston rod 31 is loosened, and the piston 3 is automatically reset under the action of the negative pressure between the piston 3 and the nut 2. When the piston 3 is reset, a negative pressure is generated in the cylinder 1 below the piston 3. The bone cement monomer in the ampoule can be sucked into the cylinder 1 through the negative pressure, and then the cylinder 1 can be shaken to make the bone cement monomer The body and the bone cement powder are uniformly mixed in the barrel 1, and then the Luer adapter 121 is removed, the nozzle is connected to the Luer connector 12 of the barrel 1, and the plug 5 is removed from the airway 33. At this time, when the quantitative piston rod 31 is pushed, the external air can enter the barrel 1 between the piston 3 and the nut 2 through the airway 33 and the vent hole 34 to balance the pressure. Pushing the quantitative piston rod 31 can quickly inject the bone cement in the barrel 1 into the patient's affected area, thereby improving the injection efficiency. When the external thread on the plastic blind tube 32 on the quantitative piston rod 31 is threadedly connected with the internal thread hole on the nut 2 and the internal thread on the T-shaped sealing ring 14, a smaller force can be used to overcome the resistance encountered in the later injection process by rotating the thread and pushing, so as to complete the injection of bone cement. Since the thread rotation direction between the external thread and the internal thread hole of the plastic blind tube 32 is consistent with the thread rotation direction between the nut 2 and the barrel 1, when the quantitative piston rod 31 is screwed to push the bone cement, the nut 2 and the barrel 1 will not reverse and loosen.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model is described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the utility model can still be modified or replaced by equivalents, and any modification or equivalent replacement that does not depart from the spirit and scope of the utility model should be included in the scope of protection of the claims of the utility model.

Claims

1. Self-priming spiral pressurized pre-filled bone cement injector, including: A cylinder, one end of the cylinder is a discharge end, and the other end of the cylinder is an open end, characterized in that: a Luer adapter is arranged on the discharge end, a filter membrane is arranged in the Luer adapter, a nut is threadedly connected to the open end, an internal screw hole is arranged on the nut, a T-shaped sealing ring is sealed in the cylinder, the T-shaped sealing ring is connected to the nut, an internal thread with the same rotation direction as the internal screw hole is arranged in the T-shaped sealing ring, a piston is movably sealed in the cylinder, a quantitative piston rod is connected to the piston, a threaded section is arranged on the quantitative piston rod, the quantitative piston rod is sealed and fitted with the T-shaped sealing ring, an airway is opened between the quantitative piston rod and the threaded section, a detachable plug is sealed on the airway, and a vent connected to the airway is opened on the quantitative piston rod.

2. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, characterized in that: The threaded section is a plastic blind tube with external threads. A reduced diameter section is arranged above the quantitative piston rod, and an annular boss is formed between the reduced diameter section and the quantitative piston rod. The plastic blind tube is sleeved and adhered to the reduced diameter section. The plastic blind tube rests on the annular boss, and the airway runs through the quantitative piston rod and the plastic blind tube.

3. The self-priming spiral pressurized pre-filled bone cement injector according to claim 2, characterized in that: The thread rotation direction between the nut and the barrel is consistent with the thread rotation direction between the nut and the external thread of the plastic blind pipe.

4. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, 2 or 3, characterized in that: The vent hole is arranged at the connection between the quantitative piston rod and the piston.

5. The self-priming spiral pressurized pre-filled bone cement injector according to claim 2 or 3, characterized in that: An annular handle is arranged on the plastic blind pipe, and a pressure bearing plate is arranged on the top of the annular handle.

6. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, characterized in that: Two arc-shaped handles are symmetrically arranged on the side wall of the cylinder.

7. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, characterized in that: A filter cavity is arranged on the Luer adapter, a filter membrane is laid in the filter cavity, a first O-ring is arranged on the side wall of the filter cavity, a Luer connector is arranged on the discharge end, the Luer adapter is threadedly connected with the Luer connector, the Luer connector is inserted into the filter cavity and abuts against the filter membrane, and the Luer connector is sealed and fitted with the first O-ring in the filter cavity.

8. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, characterized in that: A sealing rubber sleeve is clamped on the piston, an expansion gap is left between the piston and the sealing rubber sleeve, the outer wall of the sealing rubber sleeve is sealingly fitted on the inner wall of the cylinder, and two annular grooves are arranged at intervals on the outer wall of the sealing rubber sleeve.

9. The self-priming spiral pressurized pre-filled bone cement injector according to claim 1, characterized in that: A second O-type sealing ring is arranged on the outer side wall of the open end, and the nut is sealed and fitted with the second O-type sealing ring.

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