JPH02157484A - Pump head for liquid injecting operation device - Google Patents

Abstract

PURPOSE:To prevent the contact between a liquid contact portion with a liquid noncontact portion at the time of assembling and keep the sterilized condition of the liquid contact portion by providing a piston which can be brought into contact with a plunger, a holder for holding the piston in a cylinder, and a means of always energizing the piston in the retracting direction in the cylinder and holder. CONSTITUTION:A coming-off preventing mechanism is provided over a holder 11 and a piston 4 to prevent the piston 4 from jumping out of the holder 11. Thereby, the through hole 9 on a pump body 1 side of the holder 11 in which a plungr 2 was placed is closed by the bottom face of the piston 4 and a required sterilization space is automatically formed in the holder 11, enabling a cylinder 6, the piston 4 and holder 11 to be removed from the pump body 1 to give a sterilizing treatment. At the time of assembling the piston 4 to the pump body 1 after finishing sterilization, assembling can be performed with the piston 4 untouched by hand and noncontact with a nonsterilized portion and, further, there is no problem even if the outer surfaces of the cylinder 6 and holder 11 which are liquid noncontact portions are brought into contact with the nonsterilized portion, to facilitate assembling.

Description

[Detailed description of the invention] [Industrial application field]

TECHNICAL FIELD The present invention relates to the structure of a pump, and relates to a pump that requires sanitary control of wetted parts in surgical devices and other applications that use pressurized liquid jets. More specifically,
Regarding the pump head. [Prior Art] In recent years, methods of applying pressurized liquid jets as surgical devices have been studied in the medical field. A plunger pump is used as part of the device to obtain pressurized liquid. Pressurized liquid is used for special purposes such as surgery, and bacteria must never be present in it, so it is essential to sterilize the wetted parts of plunger pumps. FIG. 4 shows a partial sectional view of a conventional plunger pump.

Problem 1 to be Solved by the Invention In a conventional pump, when sterilizing the wetted parts, the parts from the pump body 1 to the piston 4. Remove cylinder 6. After each individual sterilization, put on sterilized gloves to prevent bacteria from adhering to the sterilized parts, and in extreme cases use tweezers to prevent the piston 4 from coming into contact with non-sterile parts. The cylinder θ was assembled to the pump body 1 with great care. Therefore, from the pump body 1 to the cylinder 6,
Removing and assembling the piston 4 was a time-consuming task that required skill. That is, in a liquid injection surgical device, a cylinder that can be fixed to a pump body by a fastening member, a plunger that is reciprocated by a driving means within the pump body, and a sealing member are provided, and the cylinder makes contact with the plunger. The object is achieved by providing a piston that is arranged such that the piston is movable, a holder that holds the piston in the cylinder, and a means that constantly urges the piston in the backward direction in the cylinder and the holder. In addition, the purpose can be quickly achieved by using an elastic member as a means for constantly urging the piston in the backward direction, by providing a sealing plug in the holder, and by filling the holder with gas. [Embodiment] The present invention will be explained below based on the illustrated embodiment. The plunger 2 is fixed to the pump main body 1 by a fastening member 6.
is arranged so as to be reciprocally driven by a driving means in the pump body 1, and a piston 4 is arranged on the pump head on the axis of the plunger 2, and is in contact with the plunger 2. A pressure member 3 is disposed on the circumferential surface of the piston 4 as means for always urging the piston 4 in the backward direction, and a seal member 12 is disposed at the front part of the piston 4 to prevent liquid leakage. There is. Therefore, when the plunger 2 is moved forward along the axis toward the pump head by the driving means within the pump body 1, the piston 4 moves forward and discharges liquid. When the plunger 2 retreats, the piston 4 is pushed back by the elastic member 3 and sucks the liquid into the cylinder 6. Further, a holder 11 for holding the piston 4 is provided on the side of the pump body 1 of the cylinder 6. Now, when sterilizing the pump device configured as described above,
By removing the fastening member 5, the cylinder 6
from the pump body 1. Since the holder 11 is fixed to the cylinder 6, it is removed from the pump body 1 while being integrated with the cylinder 6. The piston 4 is retracted by the elastic member 3 to a retracted end position within the holder 11. A falling-off prevention mechanism is provided across the holder 11 and the piston 4 so that the piston 4 does not jump out of the holder 11. Therefore, the through hole 9 on the side of the pump body 1 of the holder 11 in which the plunger 2 was disposed is closed by the bottom surface of the piston 4, and a necessary sterilization space is automatically created in the holder 11. The cylinder 6, the piston 4. The holder 1 is removed from the pump body 1 and sterilized. After sterilization, when assembling the piston 4 into the pump body 1, the piston 4 can be assembled without touching the piston 4 and without contacting with non-sterilized parts. Since the outer surface of part 1 is a non-wetted part, there is no problem even if it comes into contact with a non-sterilized part, and assembly can be easily performed. ! Figure s2 shows another embodiment, in which a pressure member 13 is disposed at the front of the piston 4. FIG. 3 shows yet another embodiment, in which the pressure member 3.
13 is not used, and the plug 1 is attached to the side of the holder 11.
A sealing member 1214.16 is installed at the front and rear of the piston 4 to prevent gas leakage and liquid leakage, and by sealing gas in the holder 11, the piston 4 is always moved in the backward direction. It is designed to urge the As the gas, an inert gas or the like is used. [Effects of the Invention] As explained based on the embodiments, according to the present invention, the structure in which the piston and the plunger are in contact with each other eliminates the need for assembling the piston to the main body pump. The attachment prevents occasional contact between the wetted parts and the non-sterilized parts, making it possible to maintain the sterilized state of the wetted parts, as well as making post-sterilization work easier and reducing work time. In addition, since it is easy to remove and assemble, it is possible to reduce lost time due to interruptions during use by replacing spare parts. : Pressure member: Fastening member: Suction valve: Through hole: Holder 2 Pressure member: Enclosure plug

Claims (3)

[Claims] (1) In a liquid injection surgical device, a cylinder that can be fixed to a pump body by a fastening member, a plunger that is reciprocated by a driving means within the pump body, and a sealing member are provided, and the cylinder is arranged so as to be able to come into contact with the plunger. 1. A pump head comprising: a piston, a holder for holding the piston in the cylinder, and means for constantly urging the piston in a backward direction within the cylinder and the holder. (2) The pump head according to claim 1, wherein an elastic member is used as the means for always urging the piston in the backward direction. (3) The pump head according to claim 1, wherein the means for always urging the piston in the backward direction comprises providing a sealing plug in the holder and sealing gas in the holder.