US2805794A - Dispensing devices for liquid or paste material - Google Patents

Description

R. AMON Sept. 10, 1957 DISPENSING DEVICES FOR LIQUID OR PASTE MATERIAL Filed Nov. 23, 1954 2 Sheets-Sheet l 7 JJG. Z.

Sept. 10, 1957 R. AMON 0 ,7

DISPENSING DEVICES FOR LIQUID OR PASTE MATERIAL Filed Nov. 23, 1954 2 Sheets-Sheet 2 g7 KARL UFFLOQIQS Patented Sept. 10, 1957 DISPENSING DEVICES FQR LIQUID R PASTE hiATERIAL Robert Anion, London, England Application November 23, 1?54, Serial No. 470,769

(Ilaims priority, application'Great Britain November 24, 1953 2 Claims. (Cl. 222143) This invention relates to dispensing devices for liquid or paste material. It is particularly, although not exclusively, concerned with such devices for holding and dispensing adhesives in the form of viscous liquids.

it has already been proposed to provide a dispensing device for liquid or paste material of the type in which a supply of material is held within a reservoir in communication with an outlet orifice at one end of the device, the orifice being normally closed by a valve member which is displaceable therefrom by the application of finger pressure to operating means projecting outwardly of the device at the end remote from the orifice. The valve member was located outwardly of the device and spring urged towards said orifice, the spring pressure being released and the valve member moved away from the orifice by the application of finger pressure to suitable operating means. Thus when in use the end of the device formed with the orifice was spaced from the surface to which the materialwas to be supplied.

it is a particular object of the invention to provide a device for dispensing liquid adhesivewhich can be used by an operator inone hand only in order to apply small quantities of adhesive over a small area on asnrface.

The device preferably ejects substantially the same quantity of adhesive for each application and, to this end, and also in order to simplify its operation, it is desirable that ejection of the required quantity of adhesive is ellected merely by pressing the device against the surface at the position required, without thenecessity for the separate actuation of operatingmeans by finger pressure.

According therefore to the present invention there is provided a dispensing'device for liquid or paste material comprising a hollow-nose-piece the internal surface of which defines a chamber adapted to receive said material, an outlet orifice formed in said nose-piece for said chamber, a valve member largely received within said nosepiece, resilientrneans urging said valve member towards said orificenormally to close the latter, an extension on said valve member arranged normally to extend through said orifice and movable inwardly towards said chamber to move said valve member away from said orifice against the. action of said-resilient means, at least a part ofsaid extension being so dimensioned as to permit the passage of said material through said orifice when said extension is moved inwardly, and piston-like means associated with said valve member within said chamber and movable therewith,- said piston-like means being dimensioned to leave a small gap between said piston-likemeans and the internal surface of the nose-piece at least over the range through which said piston-like means is movable. Preferably the gap between the piston-like means and the internal surface of the nose-piece is of annular form and is of from A mm; to 2 mm. depending upon the viscosity of the material, liquidor paste.

in order that the invention may be more clearly understood some examples thereof will now be described as applied to adhesive dispensing devices, reference being made to the accompanying dravings in which:

Figure 1 shows in sectional elevation a dispensing device for an adhesive in the form of a viscous liquid, the valve member being shown in the closed position;

Figure 2 shows on a larger scale the lower end of the device of Figure 1 with the valve member in the fully open position;

Figure 3 shows partly in elevation and partly in section,'a cartridge-type reservoir suitable for use with the device shown in Figures 1 and 2 or Figures 4 and 5;

Figure 4 is a view similar to Figure 2 of a modified device;

Figure 5 is a view similar to Figure 4 showing the valve member in the closed position;

Figure 6 is a section taken on the line VI-VI of Figure 4;

Figure 7 is a section taken on the line VlIVII of Figure 4;

Figure 8 is a section taken on the line VlliVlll of Figure 9 of an alternative device some parts being seen in elevation; and

Figure 9 is a section taken on the line IX-IX of Figure 8.

Referring to the example illustrated in Figures land 2 of the drawings, the device comprises a substantially cylindrical bodyportion 1 having a closed upper end 2 and an open, internally threaded end 3. A hollow cap or nose-piece 4h'aving an internalsurface which defines a chamber Sis-open at one end and is externally threaded for engagement with the threaded end 3. of the body portion 1. The other, or lower, end 6 of the cap or nosepiece 4 is substantially hemispherical in cross-section internally and is formed With an outlet orifice 7 of circular cross-section. The outer marginal surface of the nose-piece 4' surrounding the orifice 7 is formed with a raised annular lip 8; The orifice 7, is disposed substantially coaxially with the body portion 1 and narrows outwardly from the chamber 5.

The cap 4 is counterbored from its open end, ,the counterbored portion terminating in a shoulder 9 and an annular support member 10, which is shown as a press fit Within the counterbore but may be screw threaded therein, rests against the shoulder 9. The support member 10 is formed with a passage 11 extending therethrough and this passage is internally threaded in such devices which are to be used with a replaceable cartridge as described below. An inwardly turned lip 12 may be formed in the member 16 at its end adjacent the shoulder 9 to reduce the cross-section of the passage 11 at that end and the other end of the passage 11 may be outwardly flared to provide a sloping shoulder 13 between the counterbore in the cap 4.and the passage 11. The annular support member 10 may be of suf'ficient length to protrude above the mouth of the cap 4. 7

An elongated valve member 14 is located largely within the chamber 5 in the cap 4 coaxially with the body portion 1 and with the orifice 7. The valve member 14 is of circular cross-section and has a base portion 15, at its upper end. as shownin the drawing, of a diameter only slightly less than the internal diameter of the cap or nose-piece 4, to leave a small annular gap between the periphery of the base portion 15 and the adjacent internal surface of the nose-piece. The radial dimension of this gap is preferably from A to mm. and remains substantially constant over the axial range through which thebase portion 15 is movable relative to the internal surface of the nose-piece 4. The base portion 15 is shown as formed with a shoulder 16 to locate one end of avcompression spring '17, the other end of which bears against the inwardly turned lip 12 formed on the annular support member 10.

Below the base portion 15,- the valve member 14 narrows considerably in a short axial length to. merge (a 3 into a tapered finger portion 18 which, as shown in Figure 1 of the drawings, normally projects into and beyond the orifice 7 and is so dimensioned as to close the orifice 7 in this position The outer end of the finger portion 18 is of substantially rounded or hemispherical form. At least a part of the length of the finger portion 18 is so dimensioned as to permit the passage of adhesive or pasty material through the orifice 7 when the valve member 14 assumes the position shown in Figure 2 in which the valve member is shown displaced inwardly by virtue of the finger portion 18 being pressed against a solid surface 19.

As shown in Figures 1 and 2 the body portion 1 may constitute the reservoir for the adhesive or pasty material. Alternatively the reservoir maybe provided by a replaceable cartridge received within the body portion 1. A suitable cartridge 20 for containing liquid adhesive is shown in Figure 3 and is circular in cross-section having an external diameter slightly less than theinternal diameter of the body portion 1 of the .device and being of a length slightly less than the distance between the support member 10. and the closed end 2 of the body portion 1. The end 21 of the cartridge is closed and its other end 22 terminates in a threaded portion 23, this threaded portion being suitable for engagement in the'internally threaded passage 11 of the support member 10. Alternatively, the end portion 23 may be engaged in some other readily disconnectible manner with a member10. As prepared, and for storage and selling purposes, the end 23 of the cartridge 20 is closed by a threaded cap 24 and sealed by a washer 25. When the device is to be loaded with a cartridge the body portion 1 is unscrewed from the cap 4, the cap 24 is unscrewed from the cartridge 20 and the threaded end 24 of the cartridge is screwed into the passage 11 in the support member 10 with its open end bearing against the inner surface of the inwardly turned lip 12. The body portion 1 is then replaced on the device.

Where the body portion 1 constiutes the reservoir the device may be refilled by unscrewing the body portion 1 from the nose-piece 4 and pouring a quantity of adhesive into the body portion 1 and then replacing the nose-piece 4. Alternatively the closed end 2 of the body portion 1 may be in the form of a detachable screw cap which may be removed for the purpose of refilling the device.

An alternative form of dispensing device is shown in Figures 4 to 7 and is similar in many respects to that described with reference to Figures 1 and 2 and like reference numerals are used to indicate like parts. In

this case the annular support member 10 is in the form v of a thin washer of relatively small radial width which is V a press-fit within'the counterbored portion of the nosepiece 4 and affords an abutment to locate one end of the spring 17. This end of the spring 17 is formed with a tail 17a which extends for a distance of the order of a third to one'half'of the length of the reservoir into the latter and substantially coaxially. therewith. This extension serves to collect any scumsuch as a skin of solidified adhesive which may form in the reservoir and prevents clogging of the orifice 7.

The externally threaded end of the nose-piece '4 is also threaded internally asshown at 26 sothat where a cartridge-type reservoir such as that indicated at 20 in Figure 3 is to be used with the device the end 22 of the cartridge 20 (which in Figures 4 and 5 is shown in chain-dotted lines) may be threaded into the nose-.

piece 4.

Itwill .be' appreciated that in both of the above described'examples the one end of the spring 17 may .be located by an abutment formed by deformation of the internal surface of the nose-piece '4 and the annular support member may be omitted. 7

Figures 8 and '9 illustrate an alternative form. of dispensing device according to this invention, this device The valve member 14 is substantially the same as that described with reference to Figures 1 and 2 but in this case the shoulder 16 omitted as the compression spring of the previous examples is replacedby a leaf spring 27 which extends for the full length of the reservoir and is in the form of fiat strip of suitable material e. g. polyvinyl chloride or spring steel. The spring 27 is turned over at both ends as at 27a and 27b to provide abutment surfaces for the rear end of the base portion 15 of the valve member 14 and a closure28 respectively. The closure 23 closm the end of the body portion remote from the orifice 7 and may be threaded into the body portion or may be a push fit. The device is assembled by first insertingthe valve member 14 into the body portion 1 until a part of the finger 13 extends through the orifice 7, inserting the spring 27 into the body portion until the end 27a abuts against the base portion 15, filling the body portion 1 and nose-piece 4 with adhesive "or pasty material and then closing the open end of the body portion by means of the closure 28. The length or" the spring 27 is such that when the closure 28 is in position the end 27b will abut against the closure 28 and the spring 27 will be bowed slightly and placed in tension. The spring 27 also acts in the same manner as the tail 17a of the spring 17 described with reference to Figures 4 and 5 in as much as it tends to collect any This adhesive substantially fills the chamber 5 on either side of the base portion'15 of the valve member 14. Whena quantity of liquid adhesive is required at a particular place on a surface 19 the outer hemispherical end of the finger portion 18 of the valve member 14. is pressed against the surface at that particular place and the valve member is moved inwardly of the nose-piece 4 against the action of the spring into the position shown in Figures 2 and '4 of the drawings. The movement of the valve member 14 produces a corresponding axial movement of the base-portion 15. The movementof the latter displaces a volume of adhesive from behind the valve member, the larger part of which flows through the annular gap between the periphery of the base portion 15 and the adjacent internal surface of the nose-piece 4 tothat part of the chamber 5 between the orifice 7 and the base portion 15. Also the pressure within the reservoir of the device is increased slightly because of the increased volume occupied by the valve member in the portion of the chamber 5 between the orifice 7 and the base portion 15 in opening the orifice 7, with the consequentcontraction ofthat portion of the chamber 5 behind said base portion. When the pressure on the device is released the hemispherical end of the finger portion 18 remains on the surface 19 and the nose-piece is urged away from the This causes the base portion- 15 to move axially towards the orifice and displace a quantity of the adhesive contained within the chamber 5 between the orifice 7 and the base portion 15. Some of this adhesive will return through the annular gap around the periphery of the base portion between the finger portion 18 and the wall of the orifice 7, this annular space being closed when the valve member 14 assumes the position shown in Figures 1 and 5. The annular lip 8 serves to limit the area over which the ejected adhesive can adhere to the outer surface of the nose-piece 4 so that when the device is withdrawn from the surface 19 a substantially uniform dot of ejected adhesive remains on the surface 19. In practice, the device is usually operated to dispense small quantities of liquid adhesive in rapid, successive operations and under these circumstances it is found that substantially the same quantity of adhesive is ejected for each operation.

Although the adhesive may comprise an air-drying glue, the dispenser according to the invention is also suitable for use with a pressure sensitive stabilised resin emulsion adhesive containing a rubber or rubber-like latex.

Further, although the valve member 14 has been described as being of the form shown in the drawings, it will be apparent that other types of valve member having a similar piston-like action could be used. For instance, the closure of the orifice 7 could be effected by a ball mounted on a stem for longitudinal movement relative to the device, the stem carrying a piston member which may be in the form of a fiat plate of a diameter slightly less than the internal diameter of the chamber 5.

It will be apparent that the length of that part of the tapered finger portion 18 which protrudes beyond the annular lip 8 governs the amount of axial movement of the base portion and the amount of adhesive ejected at each operation of the device. It will also be apparent that the speed with which the valve member is displaced also influences the amount of adhesive ejected, a quicker stroke increasing the quantity owing to the fact that the proportion of adhesive displaced by the base portion which returns through the annular gap around the periphery thereof to the rear of the base portion is reduced.

Further, that part of the tapered finger portion 18 protruding beyond the annular lip 8 causes any adhesive which may have dried around it to be broken up when the device is next operated.

Although the end 6 of the nose-piece 4 has been described as being substantially hemispherical internally, it can assume other forms, e. g. it may be of substantially conical or frusto-conical form. Also the nose-piece 4 may be of any suitable material, e. g. metal or a synthetic resin pastic material. The nose-piece 4 may be of a slightly resilient material such as polyvinyl chloride so that when the finger portion 18 is pressed on the surface 19 to assume the position shown in Figures 2 and 4 the end 6 of the nose-piece 4 is slightly distorted to enlarge the orifice 7 through which the adhesive is ejected.

What I claim is:

l. A dispensing device for liquid or paste material comprising a hollow nose-piece the internal surface of which defines a chamber adapted to receive said material, an outlet orifice formed in said nose-piece, an abutment lo- 6 cated on the internal surface of said nose-piece, a valve member of outwardly narrowing cross-section largely received within said nose-piece and formed with a surface intermediate its length adapted to close said orifice whereby in the closed condition of the device a part of the valve member which is capable of passing through said orifice projects through the latter to the exterior of the nose-piece and a part of said valve member extends into said chamher away from said orifice, said projecting part of said valve member being movable into said orifice toward said chamber to displace said valve member and to open said orifice, piston-like means connected to the end of the inner part of the valve member remote from said orifice and extending across said chamber to sub-divide the latter into two spaces one of which communicates with said orifice, said piston-like means being movable with the valve member to increase the volume of said one space when said valv member is moved in the direction to open said orifice, said piston-like means having a diameter slightly less than the internal diameter of said chamber thereby leaving a small annular gap between its periphery and said internal surface at least over the range through which it is movable, resilient means arranged to urge said surface of the valve member toward said orifice to close the latter, said resilient means comprising a compression spring arranged to abut against said abutment at one end and to engage said valve member at the other end, said one of which is formed with a. tail extension which extends away from said valve into said material in a direction substantially parallel to the direction of movement of said'valve member, whereby said extension serves as a scum collector for said material and prevents clog ing of said orifice.

2. A device in accordance with claim 1 including a reservoir for said material and means for detachably connecting said nose-piece to said reservoir whereby said tail extension extends into said reservoir.

References Cited in the file of this patent UNITED STATES PATENTS 141,628 Chaput Aug. 12, 1873 1,600,095 Casaclang Sept. 14, 1926 1,791,350 Caron Feb. 3, 1931 1,989,738 Carson Feb. 5, 1935 2,045,926 Reutter June 30, 1936 2,192,479 Nissen Mar. 10, 1940 2,199,947 Benofsky et a1. May 7, 1940 2,429,003 Trapet Oct. 14, 1947 2,628,005 Keeshan Feb. 10, 1953 2,694,512 Morris Nov. 16, 1954 FOREIGN PATENTS 329,314 Great Britain May 14, 1930 54,172 France Dec. 17, 1947 (Addition)

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