EP1486261A1

EP1486261A1 - Pump unit and container

Info

Publication number: EP1486261A1
Application number: EP03712677A
Authority: EP
Inventors: Akira c/o Advanex Inc. MIZUOCHI; Kiyoshi c/o Advanex Inc. CHIKASHIGE
Original assignee: Advanex Inc
Current assignee: Advanex Inc
Priority date: 2002-03-15
Filing date: 2003-03-13
Publication date: 2004-12-15
Also published as: AU2003220863A1; WO2003078074A1; EP1486261A4

Abstract

The invention provides a pump unit and container wherein outflow of liquid is prevented while not in use during transport and the like, and deterioration in operability due to compression of bellows over a long period of time is also prevented. The pump unit of the present invention is inserted in a container main body Y and sucks out liquid in the container main body Y to the outside of the container main body Y, and is provided with: an intake pipe 63 inserted into the container main body Y; a bellows 64 capable of return movement in the direction of extension, and connected to an upper part of the intake pipe 63; and a piston part connected to an upper part of the bellows 64, which extends and contracts the bellows 64, and sucks out liquid in the container main body Y from a piston head P to the outside of the container main body Y via the intake pipe 63. Moreover, the piston part is able to be extended and contracted so that the piston head P can be stored on the container main body Y side the bellows 64 being contracted.

Description

TECHNICAL FIELD

The present invention relates to a pump unit and container employed in liquid pump-type containers in, for example, domestic applications.

BACKGROUND ART

Pump-type containers are conventionally employed as containers to contain liquids such as hair shampoo and detergent and the like in, for example, domestic applications. This pump-type container comprises a container main body, and a pump unit inserted in the container main body such that it may be fitted and removed. In the pump unit, when a piston part is pressed, liquid is sucked up from the container main body when the compressed piston part returns, and when the piston part is pressed again, the liquid is discharged from the discharge opening.
As disclosed, for example, in Japanese Unexamined Patent Application, First Publication No. Hei 10-101115 and Japanese Unexamined Patent Application, First Publication No. Hei 10-211947, in this type of pump unit, return movement wherein the piston part is pressed and a bellows tube is contracted, and when the piston part is released, is again extended, is employed to suck liquid up into the bellows tube, and the piston part is pressed again to contract the bellows tube and discharge the liquid in the bellows tube from the discharge opening. Liquid is introduced to the bellows tube in response to the pressing and return operation of such a piston part, or an intake valve and discharge valve are provided upstream and downstream respectively of the bellows tube to discharge liquid from the bellows tube.
However, with these conventional pump units, when the container is tipped over the intake valve and discharge valve open, and liquid may flow from the discharge opening.
To resolve such problems, the intake valve or discharge valve, or both, are conventionally plate valves having a slit part, so that the amount of liquid flowing is minimized by the slit part if the container is tipped over
FIG. 19 is a drawing showing an example of a pump unit with at least one valve being a plate valve provided with a slit part. In FIG. 19 the symbol Y indicates a container body containing liquid such as hair shampoo and detergent or the like.
The plastic container body Y is tube-shaped with an upper opening part 10 wherein a male-threaded part 11 is formed. A plastic cap 13 wherein a female-threaded part 12 is formed is screwed onto the male threaded part 11 such that it may be freely fitted and removed, and a pump unit VU is fitted to an upper opening part 10 of the container main body Y with this cap 13.
The pump unit VU is provided with; a plastic case 14 fitted into the container main body Y in the upper opening part 10 of the container main body Y, a plastic guide member 15 fitted to the case 14, a plastic bellows unit 16 inserted into the container main body Y, and a plastic piston part PI fitted to the bellows unit 16.
The case 14 is a tube-shaped member having a flange part 17 fitted onto the upper end of the upper opening part 10 of the container main body Y, and is provided with an opening part 18 in the base part. Furthermore, a female-threaded part 19 is formed in the inner peripheral face at the top of the case 14, and the guide member 15 is screwed into this female-threaded part 19.
The guide member 15 is provided with a male-threaded part 20 screwed into the female-threaded part 19, and a retaining part 22 positioned inside the male-threaded part 20 so that the suction pipe 21 of the piston part P is able to slide freely. The male-threaded part 20 and the retaining part 22 are integral at the top, and are mounted in mutually opposite directions. Moreover, a flange part 23 is formed on the upper face of the cap 13 by extending the top of the retaining part 22 and the male-threaded part 20 outwards in the lateral direction, downwards, and then outwards again, this flange part 23 preventing movement in the direction of removal (upwards). Furthermore, a lock screw part 24 is formed on the outer periphery of the guide member 15. This lock screw part 24 is screwed into the female-threaded part 26 formed on the inner peripheral face of a cap-shaped press part 25 provided in the piston part P, and locks the piston part P in the stored position.
The bellows unit 16 is inserted into the container main body Y, and sucks the liquid in the container main body Y to the outside of the container main body Y As shown in FIG. 20, the bellows unit 16 is provided with an intake pipe 27 inserted in the container main body Y, and the lower end of the intake pipe 27 is cut obliquely to form an intake end 32. Moreover, a bellows 28 capable of return movement in the direction of extension (up-down) is connected to the upper end of the intake pipe 27. The bellows 28 is provided with the required spring constant by a plastic member capable of return movement in the direction of extension, that is to say, the direction wherein the internal volume is increased, and the liquid is contained in the inside.
A connecting part 29 connected to the suction pipe 21 of the piston part P is formed integrally with the top of the bellows 28. Moreover, the upstream side of the bellows 28, that is to say, between the intake pipe 27 and the bellows 28, is provided with a valve B permitting only inflow of liquid to the bellows 28 from the container main body Y On the other hand, the downstream side of the bellows 28, that is to say, between the bellows 28 and the connecting part 29, is provided with a non-return valve G permitting only outflow of liquid to the suction pipe 21 of the piston part P from the bellows 28. A slit plate 29 described later is provided downstream of this non-return valve G.
The valve B is provided with a valve chamber 30 formed integrally with the intake pipe 27 and the bellows 28, and the non-return valve G is provided with a valve chamber 31 formed integrally with the connecting part 29 of the suction pipe 21 and the bellows 28. Furthermore, valve bodies 33 able to be inserted from the intake end 32 of the intake pipe 27, and the end of the connecting part 29 of the suction pipe 21, respectively are provided in the valve chambers 30 and 31.
In the example in the drawing, the valve bodies 33 are plastic spherical bodies, however, provided each opening part K can be blocked, its shape is not restricted and may be bowl-shaped or hemispherical and the like.
In this case, as shown in FIG. 21, a ridge 34 is formed between the intake pipe 27 of the valve B and an opening part K. As a result, if the valve body 33 inserted from the intake end 32 of the intake pipe 27 is not inserted with a given or greater force, it cannot be forced into the valve chamber 30, and moreover, the valve body 33 is prevented from leaving the valve chamber 30.
Furthermore, as shown in FIG. 20, a projection 35 is formed downstream of the valve B and the non-return valve G to prevent the valve bodies 33 floating in the valve chambers 30 and 31. This projection 35 is formed at the same time as the valve B and the non-return valve G. If floating of the valve bodies 33 can be prevented, then in place of the projection 35, the cross-sectional shape of the valve chambers 30 and 31 may be of a shape preventing the valve bodies 33 from floating, for example, an unusual shape such as elliptical, rectangular, or triangular and the like.
Here, a constricted part 36 engaged with the opening part 18 (shown in FIG. 19) of the case 14 is formed at the boundary between the valve B and the lower part of the bellows 28, and this engagement ensures that the bellows unit 16 is engaged with the case 14, so that when the bellows 28 is compressed, the bellows unit 16 is supported from below.
On the other hand, a stepped part 37 is formed at the boundary of the non-return valve G and the connecting part 29 of the suction pipe 21, and the bellows 28 is prevented from moving upwards by the contact between this stepped part 37 and the lower edge of the retaining part 22 of the guide member 15.
The intake pipe 27, valve B, bellows 28, non-return valve G, and connecting part 29 and the like configured in this manner are formed integrally by blow forming, and the bellows unit 16 is configured by pressing each valve body 33 into the valve chambers 30 and 31 of the valve B and non-return valve G.
As shown in FIG. 22, a slip plate (plate) 39 is positioned between the end of the connecting part 29 and the stepped part D formed in the insertion part 38 of the suction pipe 21 at the end of the connecting part 29 of the suction pipe 21. This slip plate 39 may be fitted to the connecting part 29 by simply inserting it, however it can be fixed in place by methods such as gluing, welding, and heat-crimped and the like.
The slip plate 39 is a thin elastic plate member as shown in FIG. 23, gripped and supported on its periphery by the connecting part 29 and the suction pipe 21, with a linear slit (orifice) S being formed in a thin part 40 towards the center.
The thin part 40 is formed gradually thinning through a portion R from the circumference, and the quality of the component is such that stress concentration does not occur due to repeated application of load. The parts S1 and S2 formed by the slit S deform elastically and bend as shown by the dotted line in FIG. 22, and when the pressure of the liquid exceeds the elasticity of the two parts S1 and S2, the liquid is suddenly discharged. Moreover, the thickness of the thin part 40 and the length of the slit S are set so that these two parts S1 and S2 do not bend when the container main body B is tipped over and the valve B and non-return valve G open, and have an elasticity such that outflow of the liquid from the slit S is prevented.
As shown in FIG. 19, by fitting the insertion part 38 of the suction pipe 21 of the piston part P forming a freely slidable L-section for the guide member 15, to the connecting part 29 of the bellows unit 16 in the configuration from above, the piston part P is fitted to the bellows unit 16, and the pump unit VU is assembled.
Here, a cap-shaped press part 25 is formed in the bend of the suction pipe 21, and the upper end of the suction pipe 21 is bent horizontally in the press part 25. The end 42 of the bent suction pipe 21 is bent slightly downwards to the opening at the discharge end 43.
The following explains the discharge of liquid with a container having the aforementioned configuration. As shown in FIG. 19, when there is no liquid in the bellows 28, pressing the press part 25 of the piston part down compresses the bellows 28 downwards as shown in FIG. 24, compressing the air in the bellows 28. As a result, the valve body 33 of the valve B closes the opening part K. However the valve body 33 of the non-return valve G opens the opening part K in an attempt to discharge air in the bellows 28, and the air is discharged from the suction pipe 21 of the piston part P.
When the press part 25 of the piston part P is released the bellows 28 attempts to return upwards, and the pressure in the bellows 28 is therefore negative. The valve body 33 of the non-return valve G then opens the opening part K as shown by the dotted line in FIG. 19, and the liquid in the container main body Y is sucked into the bellows 28, and the bellows 28 is filled with liquid (the state shown in FIG. 19).
Next, when the press part 25 of the piston part P is pressed again as shown in FIG. 25, the valve body 33 of the valve B blocks the opening part K and thus prevents movement of the liquid in the bellows 28 to the container main body Y. In association with the compression of the bellows 28, the liquid therefore presses the valve body 33 of the non-return valve G upwards, the opening part K opens, and the liquid is forced out. The liquid in the raised piston part P does not backflow into the container main body Y, and passes through the suction pipe 21 and is discharged at the discharge end 43.
Here, as shown in FIG. 25, when the non-return valve G opens and liquid is discharged from the suction pipe 21, the two parts S1 and S2 separated by the slit S in the slit plate 39 are subject to pressure in the direction of increased area of the opening of the slit S. When the liquid pressure exceeds the elasticity of the parts S1 and S2, the two parts S1 and S2 deform elastically as shown in FIG. 25, and the liquid is suddenly discharged, and the liquid can be discharged rapidly in one action.
Furthermore, this configuration has the advantage that outflow of liquid to the exterior can be prevented with the slit plate 39 when a container fitted with the pump unit VU is tipped over, even if the valve B and the non-return valve G are opened. When the container is not tipped over, any tendency to force the liquid from the bellows 28 due to an increase in pressure in the bellows 28 can be prevented with the slit plate 39. Outflow of liquid from the discharge end 43 when the container is not tipped over can therefore be prevented.
Since the liquid does not flow unnecessarily from the discharge end 43 of the suction pipe 21 in this manner, the container has the advantage of ease of use. Moreover, if the state wherein the container is tipped over is considered, considerable freedom in design is achieved by the ability to adjust the elasticity of the two parts S1 and S2 separated by the slit S, by the thickness of the thin part 40 of the slit plate 39 and the length of the slit S.
FIG. 26 shows the state of storage during transport and the like prior to use of the container. In the stored state, the female-threaded part 26 of the press part 25 of the piston part is screwed into the lock screw part 24 of the guide member 15. In this case, the push-stroke of the piston part is at its maximum. In the stored state, since the piston part P is not pressed any further, outflow of the liquid is prevented by the pressure of the piston part P. Furthermore, even if the container is tipped over in the stored state, outflow of the liquid is prevented by the existence of the slit plate 39.
This type of container is normally packed with the piston part P pressed down as shown in FIG. 26 to ensure that packing losses do not occur, for example when shipping product and the like, during transport.
However, if the piston part is pressed down for a long period of time, with the bellows 28 remaining compressed, the elasticity of the bellows 28 deteriorates, and the bellows 28 does not return sufficiently when compression of the bellows 28 by the piston part is released. As a result, the liquid then cannot be sufficiently sucked up, and operability may deteriorate dramatically.
The present invention addresses the aforementioned situation, with an object of providing a pump unit and container in which outflow of liquid while not in use during transport and the like is prevented, and also deterioration in operability due to compression of the bellows over a long period of time is prevented.

DISCLOSURE OF INVENTION

The present invention relates to a pump unit inserted in a container main body which sucks liquid inside the container main body to outside the container main body. This pump unit is provided with: an intake pipe inserted in the container main body; a bellows capable of return movement in the direction of extension, and connected to an upper part of the intake pipe; and a piston part connected to an upper part of the bellows which extends and contracts the bellows, and discharges liquid in the container main body from a piston head to the outside of the container main body via the intake pipe. Moreover, in the pump unit of the present invention, the piston part is formed such that it is able to be extended and contracted so that the piston head can be supported in the container main body without the bellows being contracted by the piston part.
According to this pump unit, the piston part is stored without compressing the bellows while not in use during transport and the like, and outflow of liquid is prevented by supporting the piston head in the container main body. Moreover, since the bellows is not compressed, deterioration in operability due to compression of the bellows over a long period of time is prevented.
Furthermore, the pump unit of the present invention is provided with: an intake pipe inserted in the container main body; a bellows capable of return movement in the direction of extension and connected to an upper part of the intake pipe; a piston part connected to an upper part of the bellows which extends and contracts the bellows, and discharges liquid in the container main body from the piston head to the outside of the container main body via the intake pipe; and a case which encloses a lower part of the piston part and the bellows in a fluid-tight manner, and in which the piston part is inserted so as to be slidable up and down. Moreover, in the pump unit of the present invention there is provided a first communicating passage in an upper part of the bellows, or on an upper side thereof, which communicates between an inside of the bellows and an inside of the case, and there is provided a second communicating passage in the piston part which communicates between the inside of the case and the inside of the piston part.
According to this pump unit, since the inside of the bellows and the inside of the case are communicated by the first communicating passage, and the inside of the case and the inside of the piston part are communicated by the second communicating passage, the bellows and piston part are communicated via the inside of the case by the first communicating passage and the second communicating passage. Therefore, liquid sucked into the bellows is accumulated not only in the bellows, but in the case on the outside of the bellows as well. When the piston part is pressed down again following accumulation of the liquid in the case as well, the bellows is compressed, forcing out the liquid in the bellows, and the volume of the section wherein liquid in the case is accumulated is reduced by the piston part, and liquid accumulated in the case outside the bellows is discharged.
In comparison to the situation wherein only liquid sucked into the bellows is discharged, liquid is discharged in an amount greater by the amount by which the volume of the case is reduced. Therefore the amount of liquid discharged can be increased without increasing the outside diameter of the case, and while suppressing cost increases.
Furthermore, in these pump units the piston part is provided with: a suction pipe (or a shaft case in the form of a pipe) connected to an upper part of the bellows; a plunger (or piston shaft in the shape of a pipe) connected by insertion through, and capable of movement in relation to, this suction pipe (or shaft case); and a piston head connected to the plunger (or piston shaft). It is desirable that the piston head be supported in the container main body, without compressing the bellows, between the suction pipe and the plunger (or the space between the shaft case and piston shaft), or on the piston part, and a locking mechanism is provided to stop relative movement between the suction pipe and plunger (or shaft case and piston case).
Since relative movement between the suction pipe and plunger (or shaft case and piston shaft) can be reliably prevented by the locking mechanism in this manner, and the piston head is stored in the container main body without compressing the bellows, outflow of liquid in the container main body is reliably prevented, and deterioration in operability due to compression of the bellows over a long period of time is reliably prevented.
Moreover, by providing the aforementioned pump unit in the container of the present invention, outflow of liquid is prevented, and deterioration in operability due to compression of the bellows over a long period of time is prevented. Alternatively, by providing the pump unit, it is possible to sufficiently increase the amount of liquid discharged with a single operation of pressing the piston part without increasing the outside diameter of the bellow. Moreover, outflow of liquid is prevented, and deterioration in operability due to compression of the bellows over a long period of time is prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of a container of the present invention, and is a cross-sectional view of the entire container with pump unit fitted.
FIG. 2 is a cross-sectional view of the pump unit of the container shown in FIG. 1 when in use.
FIG. 3 is a partial cross-sectional view of the container shown in FIG. 2.
FIG. 4 is a cross-sectional view of the pump unit of the container shown in FIG. 1 when stored.
FIG. 5 is a cross-sectional view of a further example the pump unit of the container of the present invention when in use.
FIG. 6 is a perspective view of a C-shaped collar.
FIG. 7 is a cross-sectional view of the pump unit of the container shown in FIG. 5 when stored.
FIG. 8 is a cross-sectional view of a further example the pump unit of the container of the present invention when in use.
FIG. 9 is a perspective view of a T-shaped stopper.
FIG. 10 is a partial cross-sectional view of the container shown in FIG. 8.
FIG. 11 is a cross-sectional view of the pump unit of the container shown in FIG. 8 when stored.
FIG. 12 is a cross-sectional view of the entire container with pump unit fitted showing a further example of the container of the present invention.
FIG. 13 is a cross-sectional view along a horizontal plane of these members explaining the mechanism to stop rotation between a shaft case and a chaplet.
FIG. 14A is drawing explaining a mechanism forming the non-return valve, and is a cross-sectional view showing the valve in the closed state.
FIG. 14B is drawing explaining the mechanism forming the non-return valve, and is a cross-sectional view showing the valve in the opened state.
FIG. 15 is a cross-sectional view of the pump unit of the container shown in FIG. 12 when stored.
FIG. 16 is a cross-sectional view of the container shown in FIG. 12 when in use.
FIG. 17 is a cross-sectional view of the entire container with pump unit fitted showing a further example of the container of the present invention.
FIG. 18 is a cross-sectional view of the pump unit of the container shown in FIG. 17 when stored.
FIG. 19 is a cross-sectional view of an entire container with pump unit fitted showing an example of a conventional container.
FIG. 20 is a cross-sectional view of a bellows unit of the container shown in FIG. 19.
FIG. 21 is an enlarged cross-sectional view of a valve chamber of a valve of the container shown in FIG. 19.
FIG. 22 is a cross-sectional view of the vicinity of a slit plate of the container shown in FIG. 19.
FIG. 23 is a drawing explaining the shape of a slit in the slit plate of the container shown in FIG. 19.
FIG. 24 is a cross-sectional view showing a piston part of the container shown in FIG. 19 lowered.
FIG. 25 is a cross-sectional view of the container shown in FIG. 19 when liquid is discharged.
FIG. 26 is a cross-sectional view of the pump unit of the container shown in FIG. 19 when stored.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 and FIG. 2 show examples of a pump unit and container of the present invention. In these drawings, reference symbol Y refers to a container main body containing a liquid such as shampoo and the like.
The plastic container main body Y is tube-shaped with an upper opening part 50 wherein a male-threaded part 51 is formed. A plastic cap 53 provided with a female-threaded part 52 is screwed onto this male threaded part 51 such that it may be freely fitted and removed, and a pump unit VU is fitted to an upper opening part 50 of the container main body Y with this cap 53.
The pump unit VU is provided with; a plastic case 54 fitted into the container main body Y in the upper opening part 50 of the container main body Y, a plastic guide member 55 fitted to the case 54, a plastic bellows unit 56 inserted into the container main body Y, and a plastic piston part fitted to the bellows unit 56. The piston part is provided with a piston head P and a plunger 66 connected to the piston head P so that it is integral with the piston head P, and a suction pipe 61 into which the plunger 66 is inserted so as to permit movement.
The case 54 is a tube-shaped member having a flange part 57 at the upper end of the upper opening part 50 of the container main body Y, and is provided with an opening part 58 in the base part. Furthermore, a female-threaded part 59 is formed in the upper inner peripheral face of the case 54, and the guide member 55 is screwed into this female-threaded part 59.
The guide member 55 is provided with a male-threaded part 60 screwed into the female-threaded part 59 of the case 54, and a retaining part 62 positioned inside the male-threaded part 60 so that the suction pipe 61 of the piston part is able to slide freely. The male-threaded part 60 and the retaining part 62 are integral at the top, and are mounted in mutually opposite directions.
The bellows unit 56 is inserted into the container main body Y, and sucks the liquid in the container main body Y to the outside of the container main body Y.
The bellows unit 56 is provided with an intake pipe 63 inserted into the container main body Y, and the lower end of the intake pipe 63 is cut obliquely. Moreover, a bellows 64 capable of return movement in the direction of extension (up-down) is connected to the upper end of the intake pipe 63. The bellows 64 is provided with the required spring constant by a plastic member capable of return movement in the direction of extension, that is to say, the direction wherein the internal volume is increased, and the liquid is contained in the inside.
A connecting part 65 connected to the suction pipe 61 of the piston part is formed integrally with the top of the bellows 64. Moreover, the upstream side of the bellows 64, that is to say, between the intake pipe 63 and the bellows 64, is provided with a valve B permitting only inflow of liquid to the bellows 64 from the container main body Y. On the other hand, the downstream side of the bellows 64, that is to say, between the bellows 64 and the connecting part 65, is provided with a non-return valve G permitting only outflow of liquid to the intake pipe 61 from inside the bellows 64. In this embodiment, a cone-shaped valve body 33' is employed in place of the spherical valve body 33 shown in the examples in FIG. 19 through FIG. 26. However the intrinsic functions of the valve remain the same irrespective of differences in shape of the valve body.
The central part of the suction pipe 61 inserted in the retaining part 62 of the guide member 55 is increased in diameter, and the lower end is connected to the connecting part 65 of the bellows 64. Furthermore, the plunger 66 sliding in the suction pipe 61 is inserted in the suction pipe 61 and is able to slide freely (able to move) in the up-down direction.
A groove 61a is formed on the inside of the top of the suction pipe 61 as shown in FIG. 2 and FIG. 3. Moreover, an enlarged part 66a is formed at the lower end of the plunger 66. The enlarged part 66a of this plunger 66 is fitted in the groove 61a formed in the suction pipe 61, and can also be removed from the groove.
When containers are packed for transport of product such as shipping and the like, the plunger 66 integral with the piston head P moves down while sliding within the suction pipe 61 when the piston head P is pressed down as shown in FIG. 4. In this case, the enlarged part 66a formed at the lower end of the plunger 66 deforms elastically to reduce the diameter of the plunger 66 as shown in FIG. 4, and rides over the groove 61a formed in the suction pipe 61. As shown in FIG. 4, the plunger 66 overriding the groove 61a is engaged with a further groove or engaging portion (not shown in the drawings) formed at the bottom inside the suction pipe 61, and is thus stored in the suction pipe 61. In this case, the enlarged part 66a formed at the lower end of the plunger 66, and the groove or engaging part, comprise the locking mechanism of the present invention.
By assembling components with the plunger 66 stored in the suction pipe 61 in this manner, the piston head P can be screwed into the opening of the container, that is to say, screwed into (supported by) the container main body, and locked with the piston head P pressed down without compressing and contracting the bellows 64. As a result, the overall length is shortened, the amount projecting upwards is reduced, and losses in packing efficiency can be prevented. Furthermore, since the plunger 66 is pressed into the suction pipe 61, the length required to press the piston head P down is absorbed in the length pressed down, and compression of the bellows 64 can therefore be prevented. Consequently, the extended state of the bellows 64 is maintained, and its elasticity is not lost. As a result, problems with return of the bellows 64 can be reliably prevented.
Moreover, when using the container, pulling the piston head P up results in the plunger 66 formed integrally with the piston head P sliding up in the suction pipe 61, as shown in FIG. 2. By sliding the plunger 66 upwards, the enlarged part 66a of the plunger 66 elastically enters the groove 61a formed on the inside of the suction pipe 61, and the enlarged part 66a engages in the groove 61a.
When the piston head P is pressed with the suction pipe 61 and the plunger 66 fitted together in this manner, the suction pipe 61 and the plunger 66 are lowered, and the bellows 64 compressed. In this case, if the fit of the enlarged part 66a and the groove 61a is set to overcome the spring force due to compression of the bellows 64 when the plunger 66 is pressed down and employed as a normal pump, the suction pipe 61 and plunger 66 remain in engagement.
In the case where, rather than with the plunger 66 pre-assembled in the suction pipe 61, as shown in FIG. 4, the suction pipe 61 and the plunger 66 are temporarily engaged (in a condition for use as a normal pump), and the plunger 66 is then pressed into the suction pipe 61 for packing, the bellows 64 is compressed with a stroke greater than with the normal suction operation, and the fit between the enlarged part 66a and the groove 61a may be set so that the fit is overcome by the spring force generated in the bellows 64 due to this compression (a force greater than when employed as a normal pump). With this method also, as in the aforementioned case, the plunger 66 is stored within the suction pipe 61 as shown in FIG. 2, and as a result, the piston head P is supported in the opening of the container, and packing efficiency can be increased without compressing the bellows 64.
Furthermore, a variety of configurations of the locking mechanism of the present invention are possible in place of the method wherein the enlarged part 66a is formed at the lower end of the plunger 66 and the groove or engaging part is formed at the lower part of the suction pipe 61.
For example, by forming a convex part in the plunger 66 or the suction pipe 61, and forming a concave part or notch in the other, and rotating the plunger 66 and suction pipe 61 relative to each other, a method (method of rotation) may be adopted wherein the convex part and concave part or notch are engaged, and relative rotation of the plunger 66 and suction pipe 61 is halted.
Moreover, by forming a male thread on the plunger 66 or suction pipe 61, and a female thread on the other, and screwing both together, a method (the screwed method) may be adopted wherein extension and compression is possible, while at the same time, relative movement between the plunger 66 and suction pipe 61 is halted. In this case, halting relative movement implies halting movement while no rotational force is applied. That is to say, with a normal, non-artificial external force, no rotational force is applied between the plunger 66 and the suction pipe 61, and in the present invention therefore, when the plunger 66 and suction pipe 61 are screwed together, movement between the members (plunger 66 and suction pipe 61) is halted.
When this method of rotation, or the screwed method, are adopted for the locking mechanism, this locking mechanism is able to lock with the piston head P supported in the container opening. In this case, a threaded part is formed on the piston head P, and the need to support the piston head P in the container opening (container main body) is eliminated, and forming of a thread on the piston head P is unnecessary.
In the example shown in FIG. 5, a collar 67 having a C-shaped horizontal cross-section is employed, and this C-shaped collar 67 covers the periphery of the plunger 66 in use, and is removed when the piston head P is stored.
FIG. 6 is a drawing explaining the C-shaped collar 67. The C-shaped collar 67 is tube-shaped, and is cut by a lengthwise cut 67a in one part of the tube to facilitate covering of the outside of the plunger 66, and thus the C-shaped collar 67 is elastic in the opening direction of the cut 67a.
As shown in FIG. 5, when the container is in use, the periphery of the plunger 66 is covered by the C-shaped collar 67, and the C-shaped collar 67 is fitted between the suction pipe 61 and the piston head P. When the piston head P is pressed in this fitted condition, the plunger 66 and the suction pipe 61 cannot move relative to each other due to the existence of the C-shaped collar 67. By pressing the piston head P down, therefore, the suction pipe 61 is pressed down, and the bellows 64 is compressed.
On the other hand, when packing containers, the C-shaped collar 67 is removed from the plunger 66, and, as shown in FIG. 7, the plunger 66 then slides inside the suction pipe 61 while moving downwards, and is stored in the suction pipe 61. By screwing the cap 53 onto the container opening in this condition, the piston head P is supported in the container opening in the stored condition.
A T-shaped stopper 68 is employed in the example shown in FIG. 8. This T-shaped stopper 68 is inserted and fitted into the cylinder part 70 in the piston head P when in use, and is removed from the piston head P when the piston head P is stored.
FIG. 8 is a drawing explaining the condition wherein the T-shaped stopper is fitted to the piston head P. The T-shaped stopper 68 has a disk 68a positioned on the upper face of the piston head P, and a member extending from the central part of the disk 68a. A liquid inflow space 68b, extending upwards from the lower end is formed in this member. A liquid outflow opening 68c is formed in the side at the upper end of the liquid inflow space 68b, and the liquid rising from the container main body Y to the liquid inflow space 68b passes through this liquid outflow opening 68c and flows into the opening part 42a of the piston head P and is discharged to the outside.
Furthermore, a projection 68d is provided in the peripheral direction on the surface of the lower part of a member having the liquid inflow space 68b. As shown in FIG. 10, this projection 68d fits in a groove 69 formed in the piston head P to prevent the T-shaped stopper 68 coming out of the piston head P. Moreover, a projection 68e is provided on the bottom face of the disk 68a. This projection 68e positions the piston head P and the T-shaped stopper 68 relative to each other. That is to say, by inserting the projection 68e into the concave part formed in the upper face of the piston head P, both are connected, and the liquid outflow opening 68c of the liquid inflow space 68b, and the opening part 42a, are opposed, and liquid is able to pass between the liquid outflow opening 68c and the opening part 42a.
Furthermore, the T-shaped stopper 68 need only be removed from the piston head P when storing the piston head P. That is to say, when the T-shaped stopper is removed, as shown in FIG. 11, the suction pipe 61 is enclosed in the cylinder 70. As a result, the suction pipe 61 is pressed down, and the bellows 64 is not compressed.
When the container is in use, the T-shaped stopper 68 is inserted into the cylinder 70 of the piston head P as shown in FIG. 8, and if the disk 68a of the T-shaped stopper 68 is pressed downwards with the lower end of the liquid inflow tube 68b of the T-shaped stopper 68 on the upper end of the suction pipe 61, the bellows 64 can be compressed via the suction pipe 61.
Other examples of the pump unit and container of the present invention are shown in FIG. 12 through FIG. 16. FIG. 12 is a container provided with the pump unit of the present invention, reference symbol 110 indicating the pump unit, and reference symbol 111 indicating the container. The container 111 comprises the pump unit 110 fitted to the container main body Y containing a liquid such as shampoo and the like.
The plastic container main body Y is tube-shaped having a bottom, and having an opening part 112a at the top on the periphery whereon a male threaded part 113 is formed. A plastic screw cap 115 provided with a female threaded part 114 screwed onto the male threaded part 113 is supported on the opening part 112a such that it may be freely fitted and removed, and the pump unit 110 is fitted to the container main body Y with the screw cap 115. That is to say, a hole (not shown in drawings) is formed in the central part of the screw cap 115, and the pump unit 110 is fitted to the container main body Y via the screw cap 115 by inserting a case 116 forming a plastic pipe through this hole. A flange 116a is formed on the outer peripheral part of the case 116, and this flange 116a contacts the inner face (bottom face) of the screw cap 115. Moreover, a packing 117 is placed on the bottom face of the flange 116a, and the inner face (bottom face) of the screw cap 115 and the upper edge part of the opening part 112a are in hermetically sealed contact via this packing 117.
Furthermore, within the case 116, a chaplet 118 is fitted to the part projecting above the screw cap 115. The chaplet 118 has an outer tube part 118a fitted to the outer peripheral part of the case 116, an inner tube part 118b inserted through the inner part of the case 116, and an upper part 118c formed immediately above the inner tube part 118b. This chaplet 118 is fitted to the upper end of the case 116, and clamps the screw cap 115 with the outer tube part 118a and the flange 116a of the case 116 so that the case 116 is locked on the screw cap 115.
The pump unit 110 is provided with the case 116, a plastic bellows 119 inserted through the case 116, a shaft case 120 connected to the bellows unit 119, a piston shaft 121, and a piston head 122. The piston part in the present invention comprises the shaft case 120, the piston shaft 121, and the piston head 122.
The bellows unit 119 is inserted into the container main body Y, and sucks the liquid in the container main body Y to the outside of the container main body Y The bellows unit 119 is provided with an intake pipe 123 inserted into the container main body Y. The lower end of the intake pipe 123 is cut obliquely to form an intake end 123a.
A bellows 124 capable of return movement in the direction of extension (up-down) is connected to the upper end of the intake pipe 123 in the case. This bellows 124 is of low-density polyethylene such that it is readily compressed by pressing down to reduce the internal volume, and when the pressing force is released, readily returns in the direction of extension to the original state to the increase internal volume, and provides the required spring constant.
Moreover, upstream of the bellows 124, that is to say, between the intake pipe 123 and the bellows 124, an intake valve 125 permitting liquid to flow only from the container main body Y to the bellows 124 is provided. The intake valve 125 provides a valve chamber 126 integral with the intake pipe 123.
A valve body 127 able to be inserted from the intake end 123a of the intake pipe 123, or the upper opening of the bellows 124, is inserted in the valve chamber 126. This plastic valve body 127 forms an open bowl-shape facing downstream (piston shaft 121 side), the outer peripheral face being in contact with the inner peripheral face of the valve chamber 126, thus preventing backflow of the liquid. Provided the valve chamber 126 can be opened and closed, this valve body 127 can be spherical or hemispherical and the like, and its shape is not restricted.
Furthermore, a rod part 127a is formed upstream of the valve body 127, and the attitude of the valve body 27 is stabilized by the rod part 127a. Moreover, a V-shaped notch 127b is formed on the periphery of the valve body 127, and this notch 127b permits liquid to drain rapidly when the valve opens, and flow towards the bellows 124.
A tube-shaped press-insert part 124a is formed at the upper end of the bellows 124, and a plastic capped tube-shaped piston base 128 is fitted in the press-insert part 124a. This piston base 128 is provided with a primary communicating hole 129 between the inside of the bellows 124 and the inside of the case 116. As explained below, this primary communicating hole 129 discharges liquid sucked into the bellows 124 from the container main body Y to the outside of the bellows 124. Provided this primary communicating hole 129 does not restrict the flow of liquid, its shape and dimensions are not restricted, and may be as desired, and of any desired number.
Moreover, a bellows unit 119 is held in a fluid-tight manner in the case 116 at the location where the valve chamber 126 is formed. That is to say, a hole (not shown in drawings) is formed in the bottom face of the case 116, and the bellows unit 119 is press-fitted into this hole, and by such processes as adhesion or welding and the like as necessary, the bellows unit 119 is fixed in a fluid-tight manner to the bottom face of the case 116.
The piston base 128 is formed with a smaller diameter than the inside diameter of the case 116, a hole (not shown in drawings) is opened in the bottom to fit the press-fitted part 124a, and a ring-groove (not shown in drawings) is formed to fit the lower end of the shaft case 120 to the upper part of the outer periphery.
The plastic shaft case 120 is tube-shaped, with its lower end part fitted to the piston base 128 so that the bottom opening is sealed, and the upper end part is inserted into the internal tube 118b of the chaplet 118, and held locked in place. A bottom female-threaded part 120a is formed on the inner face of the lower end part, and an upper female-threaded part 120b is also formed on the inner face of the upper end part, of the shaft case 120. A thread is not formed between the bottom female-threaded part 120a and the upper female-threaded part 120b. Furthermore, the bottom female-threaded part 120a, together with the male-threaded part 121a of the piston shaft 121 explained below, comprises the locking mechanism of the present invention.
Moreover, the lower end part of the shaft case 120 is provided with a secondary communicating hole 130 between the inside of the case 116 and the inside of the shaft case 120. This secondary communicating hole 130 passes liquid discharged from the inside to the outside of the bellows 124 and collected in the case 116, into the shaft case 120 as explained below. In the same manner as for the primary communicating hole 129, provided this secondary communicating hole 130 does not restrict the flow of liquid , its shape and dimensions are not restricted, and may be as desired, and of any desired number.
Furthermore, a ridge 131 is formed on the outer peripheral part of the shaft case 120 in the longitudinal direction of the shaft case 120. As shown in FIG. 13, this ridge 131 fits into a groove 132 formed in the inner tube part 118b of the chaplet 118, and functions as a rotation stop to prevent rotation of the shaft case 120 together with the piston head 122 when it rotates as explained below. The ridge 131 is able to move in the longitudinal direction of the groove 132, and movement of the shaft case 120 up and down in association with pressing of the piston head 122 as explained below is therefore not hindered by the fit of the ridge 131 and groove 132.
Moreover, at approximately the mid-part of the outer peripheral part of the shaft case 120, a projection 133 is formed around the periphery. Provided that this projection 133 is formed so that it avoids interference with the ridge 131, it can be formed as continuous or intermittent over its entire length.
Furthermore, a piston ring 134 is attached on the outer peripheral part at the lower end of the shaft case 120. As shown in FIG. 14A, this piston ring 134 comprises an inner ring 134a positioned on the shaft case 120 side and an outer ring 134b positioned on the case 116 side provided between the projection 133 and the peripheral part 128a of the piston base 128, integrally connected with the center part in the thickness direction of each. The upper side of the inner ring 134a is in contact with, and readily able to slide in relation to, the shaft case 120, and the thickness of the bottom side of the inner ring 134a is less than that of the upper side. The inner ring 134a therefore does not block the secondary communicating hole 130. The outer ring 134b is in close contact with the inner peripheral face of the case 16 to ensure sufficient fluid-tightness, and is formed so that it is able to slide, and the upper and lower ends form lip parts (not shown in drawings) to ensure satisfactory fluid-tightness and sliding.
Here, under normal conditions (with the piston head 122 pressed down) as shown in FIG. 12 and FIG. 14A, the space between the projection 133 and the peripheral part 128a of the piston base 128 is sufficiently wider than the overall length of the inner ring 134a of the piston ring 134. Moreover, in this state, the piston ring 134 is pressed onto the peripheral part 128a of the piston base 128, and the secondary communicating hole 130 is blocked in a fluid-tight manner by the inner ring 134a of the piston ring 134. In this manner, the secondary communicating hole 130 is blocked in a fluid-tight manner by the piston ring 134 and the piston base 128, or, as explained below, by opening the secondary communicating hole 130, the piston ring 134 and the piston base 128 function as a discharge valve to discharge liquid.
As shown in FIG. 12, an air hole 135 is formed in the case 116 above the highest position of the piston ring 134. This air hole 135 connects the inside of the container main body Y to the outside via the gap between the case 115 and the inner tube part 118b of the chaplet 118, and the gap between the case 115 and the outer tube part 118a of the chaplet 118, and thus prevents collapse of the container main body Y when the volume of liquid in the container main body Y changes.
Furthermore, the upper side of the case 116, determining the range of movement of the piston ring 134 is of larger diameter than the bottom side enclosing the bellows 124.
The piston shaft 121 is connected to the shaft case 120, and is inserted into and able to move within the shaft case 120, and a male-threaded part 121a is formed on its lower end. The male-threaded part 121a is formed such that it is able to be screwed into the bottom female-threaded part 120a and the upper female-threaded part 120b. That is to say, the piston shaft 121 is able to be connected integrally to the shaft case 120 at the position wherein the male-threaded part 121a is screwed into the bottom female-threaded part 120a, or the upper female-threaded part 120b, of the shaft case 120. In particular, when the male-threaded part 121a is screwed into the upper female-threaded part 120b, the piston shaft 121 and the shaft case 120 are able to move integrally in the axial direction (up-down).
Moreover, as explained above, the male-threaded part 121a and the bottom female-threaded part 120a comprise the locking mechanism of the present invention. That is to say, when the male-threaded part 121a is screwed into the bottom female-threaded part 120a, relative movement between the shaft case 120 and the piston shaft 121 (movement in relation to the force acting in the axial direction) is halted. However the bellows 124 is not compressed, and the piston head 122 moves towards the chaplet 118 (towards the container main body Y).
The piston head 122 is comprised of the head body 122a connected integrally to the upper end of the piston shaft 121, and the discharge pipe 122b communicating with the piston shaft 121. The head body 122a is fitted around the periphery of the outer tube part 118a of the chaplet 118 and is able to be freely fitted and removed. The discharge pipe 122b communicates with the piston shaft 121, and discharges liquid in the container main body Y from the tip opening.
The following explains the method of use of the container 111 provided with the pump unit 110 of the aforementioned configuration.
As shown in FIG. 15, while not in use during transport and the like, the piston head 122 is pressed down and rotated, and the male-threaded part 121a of the piston shaft 121 is screwed into the bottom female-threaded part 120a of the shaft case 120. In this state, the piston shaft 121 is stored inside the shaft case 120, and the piston head 122 is fitted in the outer tube part 118a of the chaplet 118. Packing and the like is therefore simplified. Furthermore, in this state, since the piston head 122 is not pressed, the liquid in the container main body Y is not discharged.
Moreover, since the piston shaft 121 stored inside the shaft case 120 does not press down the shaft case 120, the bellows 124 is not compressed and remains extended. Consequently, the situation where the bellows 124 is continually pressed down for a long period of time and becomes permanently set, does not occur.
Furthermore, in this state, since the secondary communicating hole 130 is blocked, the inside of the case 116 does not communicate with the bellows 124 side and shaft case 120 side, and the liquid in the container main body Y and the bellows 124 does not flow from the discharge pipe 122 via the shaft case 120, even if the container 111 is unexpectedly tipped over.
Moreover, since the piston shaft 121 is not exposed to the outside, it can be protected from contamination.
To use the container 111 in the state as shown in FIG. 15, the user rotates the piston head 122 to unscrew the male-threaded part 121a of the piston shaft 121 and the bottom female-threaded part 120a of the shaft case 120, and after pulling the piston head 122 upwards, again rotates the piston head 122 to screw the male-threaded part 121a of the piston shaft 121 into the upper female-threaded part 120b of the shaft case 120, and lock the piston shaft 121 and the shaft case 120 together. As a result, the container 111 assumes the state of use as shown in FIG. 12. In this case, the bottom female-threaded part 120a and the upper female-threaded part 120b are not continuous, and the piston head 122 is therefore temporarily pulled upwards, and screwed in again. By this operation of pulling up the piston head 122, the inconvenience of moving the piston head 122 up and down inside the shaft case 120 can be avoided, particularly when the shaft case 120 is long. A construction may be employed where, at the time of engagement of the male-threaded part 121a with the upper female-threaded part 120b, then without rotation of the piston shaft 121, the piston shaft 121 is pulled upwards and forcibly fitted in the shaft case 120.
In this state, pressing the piston head 122 lowers the piston shaft 121 and the shaft case 120 integrated with the piston shaft 121, and thus the bellows 124 is pressed by the piston base 128 connected to the shaft case 120 and compressed.
Furthermore, when the piston head 122 is pressed down in this manner, the shaft case 120 and the piston base 128 are lowered as shown in FIG. 14B, and these positions are displaced downwards in relation to the piston ring 134 in close contact with the inner face of the case 116. The lower end of the inner ring 134a of the piston ring 134 and the peripheral part of the piston base 128 are then separated, and the secondary communicating hole 130 opens, thus permitting communication between the case 116 and the inside of the shaft case 120. Since the projection 133 is formed in the shaft case 120, when the piston head 122 is pressed further after the secondary communicating hole 130 opens, the inner ring 134a of the piston ring 134 is pressed down together with the shaft case 120 due to the projection 133.
When the shaft case 120 is pressed down in this manner, the air in the bellows 124 is compressed and the intake valve 125 is closed, and the air in the bellows 124 therefore flows into the case 116 via the primary communicating hole 129, into the shaft case 120 via the secondary communicating hole 130, and is discharged to the outside via the hole in the piston shaft 121 and the discharge pipe 122b.
When the piston head 122 is no longer pressed, the bellows 124 returns in the direction of extension and resumes the state as shown in FIG. 12, and the pressure in the bellows 124 therefore becomes negative. Moreover, in association with the return of the bellows 124 in the direction of extension, the piston base 128 rises, and as a result, the piston ring 134 is pressed up onto the piston base 128. The piston base 128 is then again in close contact with the inner ring 134a of the piston ring 134, and the secondary communicating hole 130 is again blocked.
In this case, the inner ring 134a of the piston ring 134 contacts the lower end of the inner tube part 118b of the chaplet 118, restricting the rise of the piston ring 134 to the necessary maximum, and as a result, sufficient adherence of the piston base 128 and the inner ring 134a can be obtained.
Furthermore, the piston ring 134 and the piston base 128 rise, blocking the secondary communicating hole 130, and thus the pressure in the inside of the case 116, and the liquid collecting part 116b formed from the space on the outside of the bellows 124, becomes negative in the same manner as for the bellows 124, in association with the increase in volume.
When the pressure in the liquid collecting part 116b and the bellows 124 becomes negative in this manner, the valve body 127 of the intake valve 125 rises and the intake valve 125 opens, the liquid in the bellows 124 is sucked up from the container main body Y via the intake pipe 123, and the bellows 124 is filled with liquid.
Next, when the piston head 122 is pressed down repeatedly, the intake valve 125 is closed, and thus backflow of the liquid in the bellows 124 to the container main body Y is prevented, and the liquid therefore flows into the liquid collecting part 116b. Moreover, new liquid flows into the bellows 124 from the inside of the container main body Y
After this, as shown in FIG. 16, when the piston head 122 is pressed down again, the intake valve 125 closes, and backflow of liquid in the liquid collecting part 116b and liquid in the bellows 124 towards the container main body Y side is prevented. The liquid in the liquid collecting part 116b and in the bellows 124 prevented from backflow towards the container main body Y side is discharged to the outside via the piston shaft 121 and the discharge pipe 122b. At this time, pressing down the piston head 122 once forces out liquid in the bellows 124, while at the same time, the piston base 128 and the piston ring 134 also reduce the volume of the liquid collecting part 116b in the case 116, and liquid in the liquid collecting part 116b is also forced out. As a result, a greater amount of liquid can be discharged than with conventional pump units. That is to say, in comparison with discharge by simple application of a force to compress the bellows 124, a greater amount of liquid can be discharged in proportion to the amount of reduction in the volume of the liquid collecting part 116b.
When the piston head 122 is no longer pressed, the bellows 124 returns upward and the pressure in the bellows 124 becomes negative as explained above, while at the same time, the pressure in the liquid collecting part 116b also become negative, and liquid is therefore sucked from the container main body Y into the bellows 124, and from the bellows 124 into the liquid collecting part 116b, and the liquid collecting part 116b and the bellows 124 are filled with liquid. In this case, the piston base 128 is in close contact with the inner ring 134a of the piston ring 134, blocking the secondary communicating hole 130, and preventing backflow of liquid from the piston head 122 towards the container main body Y.
In the aforementioned operation, since the inside of the container main body Y communicates with the outside of the container main body Y via the air hole 135, then when liquid is discharged from the inside of the container main body Y, an amount of air equivalent to the amount of liquid discharged flows in from the outside. Consequently, the container main body Y is maintained in its approximately original shape without collapse.
The primary communicating hole 129 is provided in the press-insert part 124a in the top of the bellows 124 in such a pump unit 110 and a container 111 employing it, and since the secondary communicating hole 130 is provided in the shaft case 120, the bellows 124 and the shaft case 120 communicate via the liquid collecting part 116b by means of the primary communicating hole 129 and the secondary communicating hole 130. Since the liquid sucked into the bellows 124 collects not only in the bellows 124 but also in the liquid collecting part 116b, when the piston head 122 is pressed after liquid is collected in the bellows 124 and the liquid collecting part 116b, liquid is therefore forced out of the bellows 124 by compression of the bellows 124, and at the same time the volume of the liquid collecting part 116b is reduced and liquid is also forced out of the liquid collecting part 116b. Therefore, in comparison with discharge by simple application of a force to compress the bellows 124, a greater amount of liquid can be discharged in proportion to the amount of reduction in the volume of the liquid collecting part 116b.
Furthermore, relative movement between the shaft case 120 and the piston shaft 121 can be reliably prevented by the male-threaded part 121a of the piston shaft 121 and the bottom female-threaded part 120a of the shaft case 120 comprising the locking mechanism, and since the piston head 122 is stored towards the chaplet 118, outflow of liquid in the container main body Y can be reliably prevented without compressing the bellows 124, and deterioration in operability of the bellows 124 due to compression of the bellows over a long period of time can be reliably prevented.
FIG. 17 shows a further embodiment of the container with the pump unit of the present invention fitted. In FIG. 17, reference symbol 140 denotes the pump unit, and reference symbol 141 the container. The same reference symbols are applied to the same component elements in the pump unit 140 and container 141 shown in FIG. 17, as in the pump unit 110 and container 111 shown in FIG. 12, and description is therefore omitted. The primary difference between the pump unit 140 and container 141, and the pump unit 110 and container 111 shown in FIG. 12 is the formation of the locking mechanism of the present invention from the male-threaded part 121a of the piston shaft 121 and the bottom female-threaded part 120a of the shaft case 120, in contrast to the formation of the locking mechanism in the piston head 140.
That is to say, in this pump unit 140 and container 141, the female-threaded part 143 functioning as the locking mechanism in the present invention is formed on the inner peripheral face of the head body 142a of the piston head 142. This female-threaded part 143 is screwed onto the male-threaded part 144 formed on the outer peripheral face of the outer tube part 118a of the chaplet 118 shown in FIG. 18. Then, by screwing the female-threaded part 143 onto the male-threaded part 144, the piston head 142 adheres to the chaplet 118, and as a result, relative movement between the shaft case 145 and the piston shaft 121 can be reliably halted (movement in relation to the forces acting in the axial direction is halted), and compression of the bellows 124 is prevented.
As a linkage method for the shaft case 145 and piston shaft 121 when in use, by formation of an engaging portion from the respective convex and concave parts (convex projection and groove) without screwing the upper female-threaded part 120b onto the male-threaded part 121a of the piston shaft 121, and by rotating this engaging portion, or by engaging in a forceful manner, the shaft case 145 and the piston shaft 121 may be linked and integrated.
Even with such a pump unit 140 and container 141 employing it, relative movement between the shaft case 120 and piston shaft 121 is reliably halted by the locking mechanism comprising the female-threaded part 143 of the piston head 142 formed such that it is screwed onto the male-threaded part 144 of the chaplet 118, and since the piston head 122 is stored towards the chaplet 118 without compressing the bellows 124, outflow of the liquid in the container main body Y is reliably prevented, and deterioration in operability due to compression of the bellows over a long period of time is reliably prevented.
Moreover, as with the example explained above, in comparison with discharge by simple application of a force to compress the bellows 124, a greater amount of liquid can be discharged in proportion to the amount of reduction in the volume of the liquid collecting part 116b.
The present invention is not restricted to the aforementioned examples, and may be variously modified provided that it does not depart from the gist of the present invention. For example, the bellows 124 may be of a configuration having a continuous helical projection, rather than the vertically continuous horizontal projections as shown in FIG. 12 and FIG. 17. Furthermore, an intake valve of conventional shape can be employed rather than a ball-shaped valve.
Moreover, the primary communicating hole 129 may be formed directly in the upper part of the bellows 124, rather than in the piston base 128 positioned in the top of the bellows 124.
Furthermore, particularly in the example shown in FIG. 12, the bottom female-threaded part 120a and the upper female-threaded part 120b are formed so that they are not continuous in the shaft case 120. However they may be continuous in the form of a single female-threaded part.

Claims

A pump unit inserted in a container main body which sucks liquid inside the container main body to outside the container main body, comprising:

an intake pipe inserted in the container main body;

a bellows capable of return movement in the direction of extension, and connected to an upper part of the intake pipe; and

a piston part connected to an upper part of the bellows, which extends and contracts said bellows, and sucks out liquid in said container main body from a piston head to the outside of said container main body via said intake pipe; and

the piston part is formed such that it is able to be extended and contracted so that said piston head can be stored on the container main body side without said bellows being contracted by said piston part.
A pump unit according to claim 1, wherein said piston part comprises: an intake pipe connected to an upper part of said bellows; a plunger inserted through and able to move in said intake pipe; and a piston head connected to said plunger; and
there is provided a locking mechanism between said intake pipe and plunger to stop relative movement between said intake pipe and plunger, in a condition with said piston head stored on the container main body side and without said bellows being compressed.
A pump unit inserted in a container main body which sucks liquid inside the container main body to outside the container main body, comprising:

an intake pipe inserted in the container main body;

a bellows capable of return movement in the direction of extension and communicating with an upper part of said intake pipe;

a piston part connected to an upper part of the bellows which extends and contracts said bellows, and sucks out liquid in said container main body to outside said container main body via said intake pipe; and

a case which encloses a lower part of the piston part and said bellows in a fluid-tight manner, and in which said piston part is inserted so that it is able to slide;

wherein a first communicating passage which communicates between an inside of said bellows and an inside of said case, is provided in an upper part of said bellows or on an upper side thereof; and a second communicating passage which communicates between the inside of said case and the inside of said piston part, is provided in said piston part.
A pump unit according to claim 1, wherein said piston part comprises: a pipe-shaped shaft case connected to an upper part of said bellows; a pipe-shaped piston shaft inserted through and able to move in said shaft case; and a piston head connected to said piston shaft; and
a locking mechanism to stop relative movement between said shaft case and said piston shaft, in a condition with said piston head stored on said container main body side and without said bellows being compressed, is provided in said piston part.
A container having a pump unit according to claim 1.
A container having a pump unit according to claim 2.
A container having a pump unit according to claim 3.
A container having a pump unit according to claim 4.