DE2001921A1 - Reciprocating liquid dispensing pump - Google Patents

Description

DIPL.-ING. KLAUS BBHN DIPL.-PHY8. ROBERT MÜNZHUBBR

P A T BN T ANWA Ii TB

8 MUNICH 22

WIDENMATfBRSTR. B. TELEPHONE (0811) 22 25 30, 295192

A 50569 January 16, 1970

Ml / Sc '

DIAMOND INTERNATIONAL CORPORATION, 753 Third Avenue New York, New York , USA

Reciprocating liquid dispensing pump

The invention relates to a reciprocating liquid dispensing pump, which usually consists of a Plastic material is made and used on portable liquid containers.

The invention relates to improvements in a such a pump, in which the pump piston is a The valve function takes over and for this reason a movement with respect to the piston rod to a limited extent can perform, in which he sits on a dispensing valve attached to the piston rod and himself lifts from this seat again in order to control in this way the connection between the pump chamber and a delivery channel which passes through the piston

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leads to the outside world. In such a pump, the piston arrangement lifted into the fully extended position by its spring, the piston itself is in the axial position Clamped direction and seals at its lower and upper end, namely with the aforementioned Dispensing valve on the one hand and with a ventilation valve on the other hand, the connection between the inside of the liquid container and the outside air controls.

According to the invention, the piston is equipped with outwardly protruding upper and lower piston collars, those of the upward or suction stroke and the downward or compression stroke of the Piston are in contact with the cylinder wall.

W According to one feature of the invention, the

lower piston sleeve with the dispensing valve during the entire upward or suction stroke of the piston assembly together, as well as in the uppermost position of the piston assembly, in this way to the dispensing channel to separate the piston assembly from the pump chamber while in the uppermost position of the piston assembly

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the upper piston cuff cooperates with the ventilation valve and closes the ventilation duct that leads to the outside of the container at the front.

The piston is usually made of a known one Elastomer plastic material is made, and such material has a tendency to shrink with age. However, such a shrinkage of the piston sleeves is completely useless, since it results in the sealing effect and the sliding contact between the piston sleeve and the cylinder wall be adversely affected.

In the invention, this shrinkage becomes effective counteracted in such a way that the piston cuffs and the valves cooperating with them are mutually shaped and arranged so that when the piston assembly by the action of its spring in the fully extended position Position xveilt, the seating of the piston cuffs causes an expansion force on the valve bodies, which expands the cuffs. Each of the usually conical Piston cuffs that expand outwards are -with a Inner sealing surface fitted where it connects to the valve

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comes into contact and is expanded. In the preferred embodiment, this expansion force is the Edge of at least one cuff pressed firmly against a surrounding sealing surface, creating an inner seal is available.

Further important properties of the invention can be seen in the fact that the assembly of such a pump by molding the piston and associated parts in such a way that the opposite ends of the piston are exactly symmetrical, is facilitated, since it does not need to be paid attention to in which direction the piston is used without adversely affecting its operation. It is also beneficial that the dispensing valve of the piston assembly is located in front of the actual piston and with the cylinder wall is in contact, allowing the valve to act as a guide and protection for the downward piston sleeve during of the insertion into the cylinder and also afterwards during the use of the pump, because of the cylinder wall in this way firmly adhering material particles that may have settled on it, removed.

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According to a further feature of the invention there is a gap between the valve stem of the dispensing valve and the piston, although the piston is the valve stem encloses, so that during the compression stroke of the piston assembly liquid freely upwards into the Can flow delivery channel of the piston assembly, and continue the piston is free in relation to the valve stem can move back and forth so that he can move himself into the Can set positions in which it performs its valve and sealing functions effectively "

The features and advantages mentioned above will become apparent from the following description of a reproduced in the drawings embodiment again significantly obviously t in which:

Fig. 1: a vertical longitudinal section through a

Liquid dispensing pump according to the invention, in which the piston assembly in the fully extended position and both the delivery channel through the piston assembly as well as the ventilation duct are sealed outside the piston assembly, to prevent the contents of the container from leaking out;

FIG. 2 is a view similar to FIG. 1, but in which

the piston arrangement at the beginning of the downward or delivery stroke is shown, in which the ventilation channel and also the delivery channel through the piston assembly is open;

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Pig. 5 is a view similar to FIG. 2 with full constantly depressed piston assembly to the end of the delivery stroke

Fig. 4 shows the same view as Figs. 2 and 5 » the piston assembly, however, already again at the beginning of the upward or suction stroke is shown, wherein the piston rests on the dispensing valve and thereby the Dispensing channel closes while leaving the ventilation channel open; and

5 shows a detail of a modified

Embodiment of the dispensing valve.

First of all, FIG. 1 should be considered, from which it can be seen that the pump according to the invention is intended for this purpose is to be used on portable containers such as bottles, the neck portion of which is shown in phantom in FIG Representation is indicated. The entire pump consists of a pump cylinder 10, which has an opening in the bay container end cap 12 penetrates and protrudes into the interior of the container. The piston assembly consists of a tubular Piston rod 14 which forms a dispensing channel 16 which leads into an outer dispensing head 18 via which the piston assembly is reciprocable by pressing intermittently downward on the dispensing head. Resetting or the upward movement of the piston assembly is brought about by the piston spring 20 commonly used.

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The piston assembly includes a combined valve and piston part 22 which is connected to the inner wall of the cylinder in FIG sliding contact and relative to the piston rod has a limited range of motion in the longitudinal direction, in which he can come into contact with a dispensing valve 24 and detach from it, which on the piston rod 14 is attached and the dispensing opening 26 controls through the piston 22 through. Is the piston assembly through their spring 20 fully extended to its uppermost position, so the piston 22 is between the dispensing valve 24 and a Ventilation valve 28 clamped and with these two valves in a sealed connection. In this position, the dispensing valve prevents the contents of the container from passing through the dispensing channel of the piston assembly to the outside, and the vent valve prevents the contents of the container escapes to the outside around the piston assembly.

The various parts and their mutual relationships will now be discussed in detail. The pump cylinder 10 hangs through the container neck into the container. It is surrounded by an annular flange JO, by which the cylinder is held in a certain position

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and is carried on the upper edge of the container neck. The splash is on the container neck through the top surface an ordinary closure cap 12 which is screwed onto the container neck. Preferably a sealing ring 3> 2 is inserted between the support flange and the container neck.

An annular wall Jk, which is radially expanded compared to the cylinder wall and onto which a collar part 36 is placed, protrudes through a central opening in the container cap and forms a centrally arranged guide opening 38 through which the piston rod is guided with the piston rod as it moves back and forth but has a sufficiently light seat so that it does not adhere to it and also allows air to enter from the outside fc into a ventilation chamber 40 which is delimited by the annular wall and the collar part. When the pump is in operation, air enters the ventilation chamber 40 from the outside through the guide opening 38 and then through one or more ventilation openings 42 in the upper section of the cylinder wall into the interior of the container, whereby the

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20.QT921

Amount of liquid withdrawn from the container by the pump has been replaced again.

The collar part 36 in the illustrated embodiment is equipped with a wall 44, which surrounds and tightly encloses the upper section of the annular wall J54, while an annular rib 46 rests against the upper end face of the annular wall 44 and is preferably welded or glued to it. The concentric walls 44 and 34 can also be glued or welded together so that their connection is liquid-tight . '■'''.

The collar hangs around the guide opening 58 36 down the ventilation valve 28, which also has a May have auxiliary sealing ring 48 which protrudes into the ventilation chamber 40 and with the piston in one cooperates in a manner to be described later. The tubular piston rod 14 is in the guide opening with so much play that there was air through this opening can occur. The piston rod 14 forms an inner one

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Delivery channel 1β for the container content, which from the dispensing opening 26 through the piston upwards in the usual manner to the dispensing head 18 at the top End of the piston rod extends, through the latter the container contents e.g. by spraying into the open is delivered. The delivery head is in the illustrated

^ th embodiment shown as a spray head, as he

is shown in detail in U.S. Patent 3 J519,894. Such a dispensing head is generally provided with an upwardly facing pinger pad 50 which is intermittently pressed with the fingers, the plunger then being depressed and then released so that it can return to its upper position under the action of the plunger spring. The emergence of the piston rod is limited with the aid of an upwardly pointing shoulder 5 ^ * which surrounds the piston rod and which then runs up against a downwardly pointing shoulder in the guide opening 38.

A valve stem 56 is attached to the piston rod and protrudes from this downwards. At this

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The dispensing valve is seated at the lower end of the valve stem at a distance from the lower end of the piston rod 14. In the illustrated preferred embodiment is the valve stem 56 with frictional engagement in the lower Inserted at the end of the delivery channel of the piston assembly and stands against a shoulder 58 in this delivery channel on, while in the channel walls a number of longitudinal channels or grooves 6O is .eformt, which the Surrounding valve stem. -

The dispensing valve 24 is frustoconical and widening downwards and has a radially projecting base ring 62 at its lower end on, with which the valve body on the cylinder inner wall slides * The base edge is however: shaped so that the contents of the container between the cylinder wall and the dispensing valve can flow freely into the piston dispensing opening 26.

In the arrangement shown in FIGS is the base edge or guide part 62 of the dispensing valve K 24 interrupted by one or more grooves 64, .so that it is indeed with the inner wall of the cylinder la sliding contact, yet liquid is free

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can pass upwards, which then through the dispensing opening 26 into the dispensing channel 16 during the Downstroke of the piston can occur in what Pig. 2 is indicated by arrows.

In a modified embodiment, such as

"The Fig. 5, the base edge or guide member 62 is ^f of the dispensing valve as a continuous annular rim designed, however, one or more passage openings are provided 64 ', the \ on extending therethrough and internally by the wall of the valve to connect radially outward result in the pump cylinder between guide part 62 * and piston 22.

It should be noted that the piston spring 20 is clamped between the dispensing valve 24 and the lower end of the pump cylinder at which it surrounds the suction port 66. The suction opening 66 is controlled by a conventional non-return ball 68 and is connected to the bottom of the container via a dip tube 70, of which only the uppermost part is shown.

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Preferably, the ^resting: lower end of spring auf.einer annular shoulder 62 which surrounds concentrically the cylinder, the suction port 66, and is equipped with a closer spring coil 74 at the end that allows the Rückschiagkügel only a limited possibility of movement during the opening of the check valve.

The dispensing opening 26 in the piston is formed by a bore in the piston through which the valve stem 56 of the dispensing valve also passes with sufficient clearance so that the container liquid can flow upwards between the valve stem and the wall of the bore and from there it can enter the hollow piston rod 14 and further the piston can move to a limited extent in the axial direction relative to the valve stem. The frictional connection between the piston 22 and the cylinder wall has the effect that the piston always lags behind the piston rod at the beginning of each stroke until the idling between piston and piston rod is passed.

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The length of the idle between piston and piston rod is determined by axially opposite one another AnIaufschuldern 76 and 78 on the piston determined and limited, which start at the lower end of the piston rod on the one hand and on the other hand at the dispensing valve.

A sealing connection between the dispensing opening 26 of the piston and the outlet channel 16 of the The piston assembly is at all times via a telescopically sliding seal between the piston and the piston rod given and in the embodiment shown in the drawing, by an upwardly extending one Sleeve 80 is formed on the piston, which surrounds the piston bore and preferably a radially protruding lip at the free end, with which the sleeve then slides in a liquid-tight manner in an enlarged cylindrical Base 82 is guided, which is formed by the lower end of the delivery channel through the piston rod will.

The inner sealing rib 28 of the annular vent valve is designed so that it fits into the

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conically widening piston sleeve upwards pushes in and in this way exerts a radially acting expansion force on the cuff when this is pushed up by the dispensing valve and the piston spring in the highest position of the piston. The inner surface the piston sleeve is thus sealing with the annular sealing rib over its entire circumference in connection. "At the same time, the outer edge of the piston sleeve is caused by this expansion force, the is exerted by the rib on the cuff, sealing against the outer auxiliary sealing rib surrounding it of the ventilation valve pressed. The interaction between the ventilation valve and piston is so that a liquid-tight closure achieved with certainty and prevents between the ventilation chamber and the air passage openings 42 on the one hand and the Guide opening 58 through the collar part 36 connection consists. The upper annular end of the outer is also seated throughout the piston’s upward stroke tapered dispensing valve "24 on the downward annular shoulder 78 of the piston, while the downwardly widening part of the valve seals itself into the inner conical surface of the downwardly, the conically widening lower piston sleeve 88 presses in. At the same time it is radial

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outwardly protruding lip of the downwardly facing sleeve 90 of the piston with the downward konjash narrowing Inner wall of the dispensing valve 24 in a sealing connection. In this way there is a double lock between pistons and dispensing valve present during the upward stroke of the piston and also in its upper end position.

The annular support shoulders 76 and 78 in the piston are arranged in the axial direction so that they either on the lower end of the ring edge of the piston rod or on the upper edge of the dispensing valve, whereby the back and reciprocating motion of the piston assembly is imparted to the piston, but with limited idle motion can perform, which is sufficient for the intended valve action of the piston. The investment buyers are also arranged so that they hit their associated run-up edges in good time that an immediate axial contact of the outward-pointing edges of the KoI-tenschetten 84 and 88 prevent either on the collar part or on the guide portion 64 of the dispensing valve 24, whereby possible damage to the sleeves and subsequent influencing of the sealing effect with the cylinder Wall is prevented.

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• 200192 T

During the transport and storage of the filled th container, which are designed with the dispensing pump according to the invention, the upper end of the piston assembly with the dispensing head is normally of one Protective cap 92 (see Fig. 1) covers the removable is attached to the collar part in the usual way, to prevent the piston part from being fully extended being unintentionally depressed, and also. to prevent it from being damaged. In. the fully extended position of the piston assembly when attached Protective cap 92, as shown in Fig. 1, the dispensing valve 24 and the piston rod 14 through the Piston spring 20 is pressed into its uppermost position, which is loaded by the run-up shafts 54 on the piston rod, is true, the piston 22 at the same time axially between the dispensing valve 24 and the vent valve 28 is clamped. The dispensing valve blocks the entry of the liquid container contents from the pump chamber into the dispensing opening 2-6 and the channel 16. The sealing seat of the piston 22 on the ventilation valve 28 is blocked the exit path for the container liquid from the container upwards through the BeIUftungswege 42 and the Ventilation chamber 40, so that through the hole opening j58

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no leakage fluid in the collar part around the piston rod can emerge.

In the first phase of the piston downward movement, which in Pig. 2 provides the downward movement of the piston rod 14 and the dispensing valve 24 initially for

: that the dispensing valve disengages from the piston 22 while the latter remains at rest in the cylinder until its upper stop shoulder 76 from the lower end of the piston rod is detected, whereupon the upper piston cuff 87 is released from the ventilation valve 28 and the piston then with the remainder of the piston assembly moving downward. The release of the dispensing valve 24 allowed allow the container liquid to flow upwards out of the pump chamber (as indicated in Fig. 2 by arrows.

ψ indicates) between the lower piston sleeve 88 and the outer conical surface of the dispensing valve 24, then over the upper end of the dispensing valve and again downwards along its inner surface, around the lower edge of the piston sleeve 90 and then up through the dispensing opening 26 in the Piston between piston and valve stem 56 and further up through the

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Dispensing channel 16, whereupon the liquid then through the Dispensing head 18 is discharged to the outside.

The subsequent opening of the ventilation valves 28 and 48 then allows air to enter the guide opening 58 in the collar part, then through the chamber 40 and the air inlet openings 42 into the container or the reverse Vieg, if this is necessary to equalize the pressure.

The dispensing valve 24 remains during the compression stroke the piston assembly removed from its seat, until the plunger is fully depressed like this is shown essentially in Fig. 3, so that the contents of the container can escape from the pump chamber as long as " until the stroke is completed.

In Fig. 4, the piston assembly is shown shortly after the start of the upward or suction stroke, which by the piston spring 20 is effected. It goes without saying that the piston 22 remains still until the dispensing valve 24 is sufficient

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that it is moved far up with its upper edge against the downward facing shoulder 78 of the Piston pushes, whereupon the piston then slides up together with the rest of the piston assembly. These initial empty movement of the piston rod 14 and the Dispensing valve 24 went over piston 22 due to that P sealing the outer conical surface of the dispensing valve Connection with the inner conical surface of the lower piston sleeve 88 comes, with at the same time the downwardly tapered inner conical surface of the dispensing valve with the lower end of the piston sleeve 90 enters into a sealing connection and thus creates a second sealing point, whereby ingress of liquid 'into the downwardly open / ie discharge opening 26 and through the piston is definitely prevented.

During the entire suction stroke of the piston arrangement, the discharge opening and the discharge channel remain closed, so that the piston fluid through the dip tube 70 and the suction port 66 around the check valve can suck around into the pump chamber, which is then squeezed out during the next compression stroke of the piston assembly will.

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The individual parts come to the end of the upward stroke back to the position shown in FIG. 1, again with the dispensing valve 24 and the ventilation valve 28, 48 comes into sealing connection with the piston.

It should be noted that in the preferred embodiment shown in the drawing, the opposite ends of the piston symmetrical to a perpendicular to the axis Midplane are so that when assembling the various Piston parts, the piston 22 placed on the valve stem 56 and this with its upper End into the lower end of the delivery channel 16 of the piston rod is pressed in with a press fit, it does not matter which side of the piston on the valve stem is attached first.

It should also be mentioned that the sealing sleeve 8O of the piston protruding upwards with the enlarged cylindrical recess 82 in the lower end of the JColt) s rod cooperates, creating a sliding telescopic

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see sealing is achieved in all relative positions of the piston to the piston rod is effective and prevents from the delivery channel 16 of the piston assembly leakage fluid escapes into the ventilation chamber 40. So if the piston assembly is in their is in the uppermost position and there is container liquid in the paths, the liquid is prevented, exit into the annulus between the lower end of the piston rod and the upper piston sleeve 84 consists, from which they then guide upwards through the piston ungs opening 38 could emerge in the collar part.

In the sealing position of the vent valve 28, 48, as described in Pig. 1 is shown, the outer conical surface of the inner sealing sleeve 28 in the

conical inner surface of the upper piston sleeve 84, whereby this is pressed radially outwards and firmly the outer collar part sleeve 48 rests, whereby an inner and outer seal is achieved while at the same time an undesired expansion of the piston sleeve 84 is limited. The upper piston sleeve is thus in

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kept their desired dimensions so that they always Works well with the cylinder wall during each upstroke of the piston.

At the same time, the outer sealing surface of the dispensing valve 24 elastically expands the latter due to the pressure of the spring * with which the valve body is pressed from below into the conical surface of the piston sleeve 88, namely so far that the dispensing valve against the downward facing shoulder j6 des Piston starts up, as a result of which a good seal is achieved and the lower edge of the piston sleeve 88 is pressed outwards in a sealing connection with the cylinder wall.

The stretching force of the spring 20 is used as long as how the piston assembly is in its highest position, to keep the sleeves of the piston stretched, thereby reducing the tendency for the plastic to shrink is peculiar, is counteracted, and also around during longer periods of time to create an effective seal between the piston and the associated valves.

■ "'-; ■■■ - Λ -V-; - - 24 ■" *

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The annular guide part 62 or 62 'of the dispensing valve is relatively stiff compared to the contacting edges of the piston collars, so that it can prevent residues or deposits from the container contents from settling on the inner wall of the cylinder, and such a guide part also serves to keep φ during inserting the piston assembly into the cylinder to guide the piston when assembling the pump. This prevents damage and / or deformation of the relatively sensitive lower edge of the piston sleeve when assembling the pump parts. Also when assembling the piston assembly prior to insertion into the cylinder, the guide portion of the dispensing valve protects the lower edge of the piston sleeve during handling and storage of this assembled subassembly.

The lower sleeve 90 of the piston doesn't just come with the contoured inner surface of the dispensing valve 24 Kind of a valve in connection and is solved by this ^ m, thereby providing a valve function along with, rather than becoming, the lower piston cup 88 Particularly good sealing during the piston stroke

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reached at what time the greater pressure above the piston assembly tends to expand the sleeve radially outward, thereby sealing it against the valve is pressed. Because of this expansion, the sleeve also closes the delivery channel 16 securely against entry of Outside air released when the outside air pressure rises or a drop in internal pressure in the container tends to penetrate into the container.

- 26 claims

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Claims (10)

PATENT CLAIMS Liquid dispensing pump with a housing containing a pump cylinder ventilation chamber and a ventilation ^E device opening which is in communication with the chamber, wherein the cylinder has an inlet opening in its lower end, which is equipped with a check valve, characterized in that a collar part (36) forms the upper end of the housing and a piston guide opening (38) in has an axial alignment with the cylinder (10), an annular ventilation valve (28, 48), depending on this collar part, surrounds the guide opening (38), a tubular piston rod ^ (14) guided up and down through the opening (38) and forms a delivery channel (16) of the pump, means (54) for limiting the upward movement of the piston rod (14) through the collar part (56) are provided, a valve stem (56) the piston rod (14) is extended in the axial direction and attached to it, a dispensing valve - 27 - 009830/1351 (24) sits firmly on this valve stem (56) at a distance from the piston rod (14), a helical compression spring (20) is clamped between the dispensing valve (24) and the lower end of the cylinder, which extends the piston rod and the dispensing valve into its uppermost limit position expresses, a piston (22) made of an elastomeric plastic material with a through hole is slidably slid onto the valve stem (56) and represents an outlet opening (26) of the pump, which stent with the delivery channel (Ίβ) in connection, this piston (22) is axially displaceable to a limited extent relative to the piston arrangement and the dispensing valve (24) and has conically outwardly widening upper and lower piston collars (84, 88) which extend in opposite directions and are in one with the cylinder inner wall during the piston stroke are wiping frictional contact, the dispensing valve · (24) is shaped and designed so that it seals during the upward stroke of the piston in di e lower piston sleeve (88) hineindrüekt, whereby the discharge opening (26) is geschlössen to prevent backflow of the liquid, "and" the vent valve (28> 48) is shaped and designed χ that it sicham end of the upward stroke of the • ■ - ■ - 28 - "■■■. ■ '.' - ■ -. 009830 / T3S1.., - --28 - The piston (22) is pressed sealingly into the upper piston sleeve (84), whereby the ventilation chamber (40) is opposite the guide opening (58) is closed. 2. Liquid dispensing pump according to claim 1, characterized characterized in that an auxiliary ring seal (48) of the * Collar part (36) concentric to the ventilation valve (28) hangs down and the vent valve (28) expands the upper piston sleeve (84) so that it is with the auxiliary sealing ring (48) comes into sealing contact when the piston is fully extended. 3. Liquid dispensing pump according to claim 2, characterized ■ characterized in that the upper and lower piston collars (84, 88) are symmetrical, whereby the piston (22) un- W is able to work depending on its installation position. 4. Liquid dispensing pump according to claim 1, characterized by means (8O, 82) for a telescopically slidable seal between the dispensing channel (16) and the dispensing opening (26) during the entire relative displacement of the piston (22) and piston rod (14) is effective. - 29 009830/1351. 5. liquid dispensing pump according to claim "" 4, characterized characterized in that the means for .telescopic sealing <;., an upward-facing sleeve (80) on the piston (22) which surrounds the dispensing opening and telescopically in the lower end of the dispensing channel (16) of the piston rod (14) is performed. . 6. liquid dispensing pump according to claim 5, characterized characterized in that the lower end of the dispensing channel has an extension (82) for receiving the sleeve (80). 7 · Liquid dispensing pump: according to claim 6, characterized in that the piston has a downwardly pointing sleeve (90) which surrounds the dispensing opening (26), and the dispensing valve (24) is equipped with an upwardly extending sleeve> which is equipped with a above flared inner surface of the valve stem (56) at a distance surrounds and serves as a valve seat for the sleeve (90) with which it during the upward, or suction stroke of the piston (22) a sealing compound forms "whereby flow of liquid through the Dispensing opening (26) is prevented, while the connection is released during the downward stroke of the piston (22), so that liquid is free ,.-30 - 00 9830/1351 can enter the dispensing opening (26) from the cylinder (10). 8. liquid dispensing pump according to claim 7 * thereby characterized in that the upper and lower sleeves (80, 90) how the upper and lower collars (84, 88) are arranged symmetrically on the piston. 9. liquid dispensing pump according to claim 1, characterized in that the maximum outer diameter of the Dispensing valve (24) is larger than the largest outer diameter of the piston (22), whereby the dispensing valve (24) serves as a guide during installation in the pump cylinder (10) and damages the piston sleeves prevented. 10. Liquid dispensing pump according to claim 1, characterized in that the piston (22) from the valve stem (56) has a radial distance, so that the liquid through the dispensing opening (26) has free flow and any Rotation of the piston (22) on the piston rod (56) is possible, whereby the liquid-tight seat of the Piston on the cylinder wall is facilitated. 009830/1351 Empty soap