GB2234673A

GB2234673A - Liquid applicator

Info

Publication number: GB2234673A
Application number: GB8917482A
Authority: GB
Inventors: Nobuyuki Nakazima; Takashi Umeno
Original assignee: Mitsubishi Pencil Co Ltd
Current assignee: Mitsubishi Pencil Co Ltd
Priority date: 1989-07-27
Filing date: 1989-07-31
Publication date: 1991-02-13
Anticipated expiration: 2009-07-31
Also published as: FR2650200A1; FR2650200B1; GB2234673B; DE3924926A1; GB8917482D0

Abstract

A liquid applicator is provided with a brush tuft (6) for applying a high-viscosity liquid such as liquid rouges. The liquid is held in a cartridge (3) which is slidably mounted in an outer shaft (4) forming a main body of the applicator. A piston member (25) is slidably and hermetically mounted in the cartridge and has its front end surface adjacent to the contents of the cartridge while exposed to atmospheric pressure on its rear-end surface. In use, when the liquid flows out of the cartridge (3), the pressure of the contents of the cartridge falls below atmospheric pressure to produce a vacuum which causes the piston member (25) to be axially displaced forwards. As a result of such displacement of the piston member (25), pressure of the contents of the cartridge (3) balances with the atmospheric pressure to make it possible for the cartridge to smoothly supply the liquid to the brush tuft (6). <IMAGE>

Description

1 t 1 1 - 15 LIQUID APPLICATOR The present invention relates to a liquid

applicator for applying liquids such as: cosmetic liquids such as nail polish and liquid rouges; inks; paints; liquid drugs; and the like, and more particularly to a liquid applicator provided with a valve unit for controlling the quantity of the liquid being applied.

Heretofore, a number of liquid applicators of this type have been proposed, an example of which is shown in Fig. 2. This example of conventional liquid applicator shown in Fig. 2 is provided with an outer shaft or sleeve-like main body 4 in which is axially slidably mounted a cartridge 3 filled with an application liquid. In a front-end opening portion of the cartridge 3 is provided a valve unit 1, while a rear-end portion of the cartridge 3 extends rearward from a rear end of the outer shaft 4 to form a so-called push-out means of the cartridge 3. A front shaft 5 is threadably engaged with an outer peripheral surface of a frontend portion of the outer shaft 4 so that a brush tuft 6 serving as a liquid-application member of the applicator is fixedly mounted in the front shaft 5. On the other hand, an 1 -1 application-liquid conduit 8 is fixedly mounted on an inner surface of the front-end portion of the outer shaft 4, a rear-end portion of which conduit 8 is inserted into the interior of the cartridge 3 so as to abut on a valve stem 9 of the valve unit 1. With a front end of the conduit 8 is connected an application-liquid guide pipe 7 a front-end portion of which is inserted into the interior of the brush tuft 6. In operation of the conventional liquid applicator shown in Fig. 2, the cartridge 3 is pushed axially forward to move the valve stem 9 rearward relative to the cartridge 3 so as to open the valve unit 1. As a result, the application liquid contained in the cartridge 3 is allowed to flow out of the cartridge to the brush tuft 6 through the conduit 8 and the guide pipe 7. Incidentally, after assembling of the liquid applicator, a front end of the applicationliquid guide pipe 7 reaches a position slightly ahead of an axially intermediate portion of the brush tuft 6 in the interior thereof.

In the conventional liquid applicator having the above construction, outside air with which the appli cation liquid filled in the cartridge 3 is replaced in use is supplied to the cartridge 3 through the brush tuft 6, guide pipe 7, conduit 8 and the valve unit 1.

However, when the viscosity of the application 1.

- 15 liquid is high, it is difficult for the outside air to flow into the cartridge 3 since the cartridge 3 forms a closed reservoir. Consequently, in the conventional liquid applicator, even in normal operation thereof, air pressure in the interior of the cartridge 3 often falls considerably below the atmospheric pressure to produce a strong vacuum which excessively sucks the outside air into the cartridge 3 to prevent the application liquid filled in the cartridge 3 from being constantly supplied to the brush tuft 6. This is a problem inherent in the conventional liquid applicator.

In addition, in the conventional liquid applica tor, there is another problem in that a part of the out side air sucked into the cartridge 3 often stays in the valve unit 1 to mix with the application liquid being supplied to the brush tuft 6. The thus mixed air prevents the brush tuft 6 from smoothly applying the application liquid. Consequently, hitherto, the user must repeat the push-out operation of the cartridge 3 a number of times to try to smoothly supply the application liquid to the brush tuft 6.

It is an object of the present invention to pro- vide a liquid applicator which resolves the above problems inherent in the conventional liquid applicator. Namely, it is an object of the present invention to provide a liquid applicator which, regardless of the viscosity of the application liquid, prevents pressure of the contents of an application-liquid reservoir cartridge from excessively falling below the atmospheric pressure, to make it possible to smoothly supply the application liquid by an appropriate amount to a brush tuft serving as a liquid-application member of the applicator, without repeating the push-out operation of the cartridge a number of times. According to a first aspect of the present invention, a liquid applicator comprises: an outer sleeve-like main body; a 11 quid- appli cation member mounted on a front-end portion of said outer sleeve- like main body; an appli cation-li quid reservoir cartridge axially slidably mounted in said outer sleeve-like main body, said cartridge being provided with a valve unit in its front-end opening portion, said valve unit being provided with a valve spring for resiliently pressing a valve stem against a valve seat; means for axially pushing said cartridge forward; an application-li quid conduit for supplying an application liquid from said cartridge to said liquid-application member through said valve unit, said conduit being provided in front of said cartridge mounted in said outer sleeve-like main body, a rear end of which conduit abuts said valve unit; an application-liquid guide pipe rigidly connected with said application-li quid conduit to communicate therewith, a front- end portion of which guide pipe is inserted into said liquid-application member, said cartridge being axially movable forwards relative to said outer sleeve-like main body to open said valve unit so as to permit application liquid to flow from said cartridge to said liqui d-appli cation member; and, a piston member slidably and hermatically mounted in said cartridge for being adjacent to the contents of the cartridge with its front-end surface while exposed to atmospheric pressure on its rear-end surface.

In the liquid applicator of the present invention, application liquid in the cartridge may be smoothly supplied to the brush tuft without being replaced with outside air in the cartridge, and may keep its supply flow rate stable. In addition, since there is no fear that outside air is mixed with the application liquid, it is possible to smoothly supply the application liquid to the brush tuft. Consequently, the problem of repeating the push-out operation of the cartridge a number of times is completely resolved so that the liquid applicator is easy to use.

According to a second aspect of the present invention, a liquid applicator comprises:

an application-li quid reservoir cartridge; a piston member slidably and hermetically mounted in said cartridge with its rear-end surface exposed to outside air; and a valve unit provided in said cartridge for controlling the flow of application liquid from said cartridge.

Fig. 1 is a longitudinal sectional view of an embodiment of a liquid applicator of the present invention; and Fig. 2 is a longitudinal sectional view of a conventional liquid applicator.

Now, a preferred embodiment of a liquid applicator of the present invention will be described hereinbelow in detail with reference to Fig. 1.

Th Fig. 1 the reference numeral 4 denotes an outer shaft or sleeve-like main body of the liquid rouge applicator; 3 an application-liquid or liquid-rouge reservoir cartridge axially slidably mounted in the outer shaft 4; 5 a front shaft threadably mounted on a front-end portion of the outer shaft 4; and 6 a brush tuft which serves as a liquid-application member of the applicator and may be replaced with one made of porous materials.

The outer shaft 4 is provided with a rear-end opening through which the cartridge 3 is inserted into the outer shaft 4 in assembling thereof. A front-end portion of the outer shaft 4 is smaller in diameter than the remaining portion of the outer shaft 4 to form a small-diameter portion 10 as shown in Fig. 1. An outer peripheral surface of the small-diameter portion 10 of the outer shaft 4 is provided with a male screw 11.

In the drawings, the reference numeral 8 denotes an application-liquid conduit provided with a tubular main body and a front-end large-diameter portion 11 in which is provided a radially outwardly extending flange 1 1 - 15 which abuts on a front-end edge of the outer shaft 4 so as to fixedly mount the application-liquid conduit 8 in the outer shaft 4.

Into the large-diameter portion 11 of the application-liquid conduit 8 is inserted a rear-end portion of the brush tuft 6, which rear-end portion is formed into a radially outwardly extending flange 13 which is fixedly sandwiched between the bottom of the largediameter portion 11 of the conduit 8 and a sealing ring 12 provided with a front-end flange 14 which abuts on the flange 15 of the large-diameter portion 11 of the conduit 8. Through these flanges 14, 15, the front shaft 5 is threadably engaged with the small-diameter portion 10 of the outer shaft 4 so that both the conduit 8 and the brush tuft 6 are fixedly mounted in the outer shaft 4.

As shown in Fig. 1, the brush tuft 6 extends forward from a front end of the front shaft 5. On the other hand, an application-liquid guide pipe 7 is fixedly mounted in the conduit 8 in its rear portion to communicate therewith, while inserted into the brush tuft 6 in its front portion to reach a substantially axial intermediate portion of the brush tuft 6.

A rear portion of the application-liquid conduit 8 extends rearward to enter the interior of the outer 1 - 15 - 8 shaft 4. In the outer shaft 4, the thus extending rear portion of the conduit 8 passes through a central opening of the cartridge 3 having been inserted into the outer shaft 4 through a rear-end opening of the outer shaft 4, so that the rear end portion of the conduit 8 is inserted into the cartridge 3 to abut on a front end of the valve stem 9 of the valve unit 1.

The cartridge 3 is filled with the application liquid, e.g. liquid rouge.

A front-end portion of the cartridge 3 is formed into a small-diameter portion provided with a front-end opening in which is fixedly mounted the valve unit 1 which is constructed of: a valve seat 22; a spring bearing 23; the valve stem 9; and a valve spring 20.

The valve unit 1 is fixedly mounted in the cartridge 3 by means of a front piece 21 which is threadably engaged with the front small-diameter portion of the cartridge 3 as shown in Fig. 1. A packing member 24 is interposed between the front piece 21 and the valve unit 1.

The cartridge 3 provided with the valve unit 1 is of known construction and operation.

The spring bearing 23 is provided with a cylindri--- 1 1 - 15 - 9 cal portion in its inner surface at a position slightly behind the valve seat 22. On the other hand, the valve stem 9 is provided with a flange-like piston portion consisting of: a radially outwardly extending rear wall part; and an annular wall part axially extending forward from an end of the rear wall part of the piston portion. The annular wall part of the piston portion of the valve stem 9 is brought into a slidable and a hermetical contact with the cylindrical portion of the spring bearing 23.

In a rear end of the cartridge 3 is provided an opening through which a piston member 25 is inserted into the cartridge 3, which opening of the cartridge 3 is closed with a tail plug 26.

The piston member 25 is brought into a slidable and a hermetical contact with the cartridge 3.

A small vent hole 28, through which the interior space of the cartridge 3 defined by the piston member 25 communicates with the outside air, is provided in the rear-end portion of the cartridge 3 at a position in the vicinity of the tail plug 26. It is also possible to provide the small vent hole 28 in the tail plug 26 In assembling of the applicator, the cartridge 3 is inserted into the outer shaft 4 through the rear opening of the outer shaft 4 to cause the rear end of the application-liquid conduit 8 to abut on the front - end of the valve stem 9. After completion of assembling of the outer shaft 4 and the cartridge 3, the rear-end portion of the cartridge 3 extends rearward from the rear end of the outer shaft 4 by a predetermined length to form a so-called push-out means.

Now, operation of the liquid applicator Of Fig. 1 will be described hereinbelow in detail.

As shown in Fig. 1, during non-use of the applica tor, i.e., in a condition in which the user does not push the rear-end portion or push-out means of the car tridge 3 axially forward relative to the outer shaft 4, the rear-end portion or push-out means of the cartridge 3 extends rearward from the rear end of the outer shaft 4. Under such circumstances, in use, when the user pushes the rear-end portion or push-out means of the cartridge 3 axially forward relative to the outer shaft 4, the cartridge 3 begins to move axially forward relative to the outer shaft 4 so that the valve unit 1 is also axially moved forward relative to the outer shaft 4. As a result, the valve stem 9 is pushed rearward relative to the car tridge 3 by the rear end of the application-liquid conduit 8 so that the valve unit 1 is opened, whereby the applica tion liquid filled in the cartridge 3 is allowed to flow out of the cartridge 3. The application' 1 Z f - 15 liquid thus flowed out of the cartridge 3 passes through the valve unit 1, conduit 8 and the guide pipe 7 to enter the brush tuft 6. At this time, pressure of the contents of the cartridge 3 falls below the atmospheric pressure to produce a vacuum which causes the piston member 25 to be axially displaced forward. As a result of such axial displacement of the piston member 25, pressure of the contents of the cartridge 3 substantially balances with the atmospheric pressure.

Consequently, in the liquid applicator of the present invention, there is no fear that the outside air is excessively sucked into the interior of the application-liquid conduit 8 through the brush tuft 6 and the application-liquid guide pipe 7 at a time when the valve unit 1 is opened, and also there is no fear that the outside air enters the interior 16 of the cartridge 3 through the air's replacing operation with the application liquid.

-12

Claims

1. A liquid applicator comprising: an outer sleeve-like main body; a liquid-application member mounted on a front-end portion of said outer sleeve-like main body; an applic ation-11 quid reservoir cartridge axially slidably mounted in said outer sleeve-like main body, said cartridge being provided with a valve unit in its front-end opening portion, said valve unit being provided with a valve spring for resiliently pressing a valve stem against a valve seat; means for axially pushing said cartridge forward; an application- liquid conduit for supplying an application liquid from said cartridge to said liquid- application member through said valve unit, said conduit being provided in front of said cartridge mounted in said outer sleeve-like main body, a rear end of which conduit abuts said valve unit; an applicat ion-11 quid guide pipe rigidly connected with said application-fi quid conduit to communicate therewith, a front-end portion of which guide pipe is inserted into said liquid-application member, said cartridge being axially movable forwards relative to said outer sleeve-like main body to open said valve unit so as to permit application liquid to flow from said cartridge to said liquid-application member; and, a piston member slidably and hermatically mounted in said cartridge for being adjacent to the contents of the cartridge with its front-end surface while exposed to atmospheric pressure on its rear-end surface.

2. A liquid applicator comprising: an application-liquid reservoir cartridge; a piston member slidably and hermetically mounted in said cartridge with its rear-end surface exposed to outside air; and 1 1 a valve unit provided in said cartridge for controlling the flow of application liquid from said cartridge.

3. A liquid applicator substantially as herein described with reference to Figure 1 of the accompanying drawings.

4. All novel features described herein and combinations thereof.

Pjblished 1991 at The Patent Office. State House, 66/71 High Holborn. London WC I R47?. Further copies rnay be obtained from Sales Branch, Unit 6, Nir- Mile Point. Cwrnfelinfach. Cross Keys. Newport. NPI 7HZ. Printed by Multiplex techniques lid. St Mary Cray. Kent