JP4170064B2 - Pump piston - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a suitable piston incorporated in a pump or the like of a pressure accumulating liquid ejector, and is intended to advantageously avoid adhesion between members that occurs in the manufacturing process of the piston.
[0002]
[Prior art]
So-called aerosol-type sprayers in which containers such as lotions, colons, and perfumes are finely sprayed are filled with a dispersion medium together with a pressurized medium have been used so far. In addition, since the manufacturing cost increases and the pressurized medium often remains in the container even after all of the dispersion medium is used up, the container is perforated and the pressurized medium is discharged before disposal. It is indispensable, and it takes time to discharge the container, and there is a concern that the release of the pressurized medium into the atmosphere may lead to environmental pollution.
[0003]
For this reason, in recent years, a pressurizing medium such as that used in aerosol type ejectors is not required, and the internal pressure is increased by pumping the spray head (pressing head) multiple times, and the content is increased with the pressure. An accumulator-type ejector designed to inject has been reviewed (for example, see Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-273279.
[0005]
An accumulator-type ejector includes a cylinder fixedly held at the mouth of a container, a piston disposed in the cylinder, a piston guide that opens and closes a passage by contact and separation associated with the reciprocating movement of the piston, and the piston It consists of a combination of a hollow stem that holds one end of the guide and the other end connected to the back surface of the piston via an elastic member, and a pressure head that has a nozzle connected to the internal passage of this hollow stem. The liquid can be continuously discharged by sucking and pressurizing the liquid inside.
[0006]
By the way, the piston that constitutes the ejector is a sliding member that reciprocates while contacting within the cylinder, and it is required to reduce the sliding resistance, and the frictional resistance with other members when the pump is incorporated. In the manufacturing process, the piston is usually dipped in a tank containing a lubricant (silicone, etc.) to form a lubricant coating layer. When the pistons are stacked in bulk, the main bodies of the pistons having the largest diameter may be adsorbed (or fixed) at their end faces, and if the piston is adsorbed (or fixed), it is put into the parts feeder. Such pistons may cause a stoppage, and it is essential to remove such pistons one by one when assembling the pump. It had become a cause of deterioration verses.
[0007]
[Problems to be solved by the invention]
The subject of this invention exists in the place which proposes the novel piston which can eliminate the above conventional problems.
[0008]
[Means for Solving the Problems]
The present invention is a piston that is disposed in a cylinder of a pump of an accumulator type liquid ejector and reciprocates in the cylinder in conjunction with a movement of a hollow stem connected to a pump pressing head and a piston guide linked to the hollow stem. And
A piston body having an opening through which the piston guide passes and an annular side wall portion slidably contacting the inner wall surface of the cylinder, and a through hole through which the piston guide which is integrally connected at the rear end of the piston body and passed through the opening is inserted It consists of an annular body that has a path and fits into the tip of the hollow stem,
A pump characterized in that at least one end face of the end face of the piston body or the end face of the annular body is provided with a plurality of protrusions for reducing the contact area at that portion to prevent the pistons from being adsorbed or stuck together. The piston. In the present invention, the pump refers to all known dispensers such as a spray type pump and a trigger type pump.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described more specifically with reference to the drawings.
[0010]
FIG. 1 is an external perspective view of an embodiment of a piston according to the present invention, and FIGS. 2 (a) and 2 (b) are front and side views (lower half shown in cross section). is there.
[0011]
1 and 2, reference numeral 1 denotes a piston body, and 2 denotes an annular body integrally connected at the rear end of the piston body 1.
[0012]
The piston main body 1 has annular seal portions 1a and 1b that slidably contact the inner wall surface of the cylinder, and an opening 1c for passing the piston guide is provided inside thereof. Further, the annular body 2 is provided with a through passage 2a through which the piston guide passed through the opening 1c is inserted, and the rear end portion thereof is fitted into the distal end portion of the hollow stem.
[0013]
Reference numeral 3 denotes a plurality of protrusions (which may be rib-shaped) shown in the example provided on the tip surface of the piston body 1.
[0014]
When a general piston incorporated in a liquid ejector is dipped into a lubricant and piled up, the pistons adsorb (or stick) to each other as shown in FIG. 3. However, since the piston according to the present invention has a plurality of projections 3 at the tip of the main body 1, the contact area at the site can be reduced and the pistons are adsorbed ( Or the frequency of sticking) is extremely low.
[0015]
In addition to the protrusion 3 having the cross-sectional shape shown in FIG. 2, the protrusion 3 may have a cross-sectional shape as shown in FIGS. 4A to 4C, and the number of the protrusions 3 is arbitrary, and this point is limited. Not. Moreover, although the case where the projection 3 was provided on the tip surface of the piston body 1 was shown, the formation location of the projection 3 is formed on at least one end surface of the end surface (end surface of the piston body 1 and the annular body 2) formed on the piston. It only has to be. When provided on two or more end surfaces, it can be provided on the rear end surface of the piston body 1 in addition to the front end surface of the piston body 1 shown in the embodiment, or on the rear end surface of the annular body 2. Depending on the shape of the piston, it may be provided on the front end surface of the annular body 2, and the end surfaces on which the protrusions 3 are provided and the number thereof can be appropriately changed according to the shape of the piston.
[0016]
FIG. 5 shows an example in which the piston according to the present invention is incorporated in a pump of a spray type liquid ejector.
[0017]
In FIG. 5, 4 is a cylinder in which a piston is arranged, 5 is a pressing head provided with a nozzle, 6 is a hollow stem connected to the pressing head 5, and 7 is a piston guide linked to the hollow stem 6.
[0018]
【The invention's effect】
According to the present invention, the frequency with which the pistons are adsorbed (or fixed) is extremely small, and there is almost no machine stop or removal work due to the adsorption (or fixation), so that an efficient assembling operation can be realized.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a piston according to the present invention.
2A and 2B are views showing the front and side surfaces of the piston shown in FIG.
FIG. 3 is a view showing an adsorption (or fixation) state of a piston.
4A to 4C are diagrams showing other examples of the cross-sectional shape of the protrusions.
FIG. 5 is a view showing a cross section of a liquid ejector.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Piston main body 2 Annular body 3 Protrusion 4 Cylinder 5 Press head 6 Hollow stem 7 Piston guide

Claims (1)

A piston that is arranged in a cylinder of a pump of an accumulator type liquid ejector and reciprocates in the cylinder in conjunction with a movement of a hollow stem connected to a pressing head of the pump and a piston guide linked to the hollow stem,
A piston body having an opening through which the piston guide passes and an annular side wall portion slidably contacting the inner wall surface of the cylinder, and a through hole through which the piston guide which is integrally connected at the rear end of the piston body and passed through the opening is inserted It consists of an annular body that has a path and fits into the tip of the hollow stem,
A pump characterized in that at least one end face of the end face of the piston body or the end face of the annular body is provided with a plurality of protrusions for reducing the contact area at that portion to prevent the pistons from being adsorbed or stuck together. Piston.

Images