United States Patent 3827601

A hand powered liquid syringe or metering dispenser particularly for use in the veterinary medicine field comprises a pump mounted in a body having a transverse handle or grip. Standard bottles or other containers for vaccines or medicines may be mounted on a fitting secured to the body to supply the pump through a piercing tube or needle secured in the fitting. Air is supplied through the fitting to replace liquid removed from the bottle and the needle and air inlet are positioned in a manner to prevent air from being discharged from the bottle with the liquid. The pump is actuated by a squeezing action on a plunger when a handle is pressed toward the pistol grip. Check valves are provided in the inlet and outlet passages of the pump. Cannulas or other liquid discharge elements may be removed from the dispenser without requiring handling by the operator; this is accomplished by a trigger mechanism actuated by the operator's hand while he is holding the pistol grip.

Magrath, Joseph M. (McCook, NB)
Hierath, Leonard L. (Denver, CO)
Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
222/324, 222/383.1, 604/183, 604/223
International Classes:
G01F11/04; A61D1/02; A61M5/162; A61M5/20; (IPC1-7): B67B7/24
Field of Search:
222/385,324,325,383,309,83,470,81,80 128
View Patent Images:
US Patent References:
2825334Hypodermic syringe for livestock1958-03-04Kas, Sr.
1986343Oil-spray gun and the like1935-01-01Iskyan
1486656N/A1924-03-11Green, Jr.

Primary Examiner:
Schacher, Richard A.
Assistant Examiner:
Slattery, James M.
Attorney, Agent or Firm:
Edwards, Esq. Wm Griffith
We claim

1. A liquid metering dispenser comprising:

2. A liquid metering dispenser as set forth in claim 1 wherein said passage is of circular configuration and the upper end of said base is conical and engages the wall of the passage in said fitting along an annular sealing line when pressing said base into position on said nipple.

3. A liquid metering dispenser as set forth in claim 1 wherein said check valve for said inlet is mounted within said base.

4. A liquid metering dispenser as set forth in claim 1 wherein said fitting includes an upper seat about said passage for receiving the neck of an inverted bottle having its seal pierced by said tube and

5. A liquid metering dispenser as set forth in claim 4 wherein said means for detachably securing a bottle on said seat comprises a plurality of locking members mounted in said fitting and a collar rotatably mounted on said fitting and positioned for engagement with and actuation of said locking members to move said members into engagement with the bottle.

6. A liquid metering dispenser as set forth in claim 1 including means for sealing said upper portion of said passage and a check valve for preventing the reverse flow of fluid from said upper portion of said passage through said air admitting means for minimizing reverse flow of fluid through said means for conducting air to the bottle.

7. A liquid metering dispenser as set forth in claim 4 wherein said locking members comprise pins slidable in said fitting toward and away from a bottle on said seat, said members including springs urging them toward said collar,

8. A liquid metering dispenser comprising:

9. A liquid metering dispenser comprising:

10. A liquid metering dispenser as set forth in claim 9 and a plurality of said cannulas, each comprising a tube having thereon a transverse disc for limiting the distance of penetration of the tube into a cavity to be treated whereby contact of the dispenser body and a treated individual is prevented and the plurality of cannulas may be used each in turn on separate individuals without contamination from previous treatments.

11. A liquid metering dispenser comprising:

12. A liquid metering dispenser as set forth in claim 11 wherein:

13. A liquid metering dispenser as set forth in claim 11 including means for attaching a standard hypodermic needle at the outlet of said body whereby said dispenser may be utilized as a hypodermic syringe.

14. A liquid metering dispenser as set forth in claim 13 wherein said mounting means for said piercing tube is of a size different from that for a standard hypodermic needle whereby said standard needle and said piercing tube are not interchangeable.

This invention relates to dispensers for liquids such as vaccines and particularly to an improved hand powered liquid dispenser of the metering type.

In treatments wherein repeated injections or applications of the same dosage of a liquid medicine or vaccine are required, it is necessary to provide a device or devices for repeatedly discharging the same quantity of the liquid. For example, in the field of veterinary medicine, when a number of animals must be treated one after another, it is time consuming to prepare and employ a separate syringe for each animal. Vaccines, for example, are supplied in bottles from which the liquid may be withdrawn by a syringe having a needle which will pierce the cap or seal of the bottle and allow the operator to withdraw a desired dosage of the liquid. It is desirable to provide an arrangement for utilizing a single device for the giving of individual treatment to a multiplicity of animals one after another without requiring a plurality of fillings of a syringe from a single bottle. Accordingly, it is an object of the present invention to provide an improved liquid dispensing device for supplying a predetermined dosage of liquid to individuals one after another.

It is another object of this invention to provide an improved hand powered dispenser for discharging a preselected dose of treating liquid each time the dispenser is operated.

It is another object of this invention to provide a liquid dispenser for discharging repeatedly a preselected quantity or dose of liquid including an improved arrangement for facilitating the use of a new injection cannula or needle for each individual operation.

It is a further object of this invention to provide a hand powered liquid dispenser including an improved arrangement for assuring the discharge of identical doses or quantities of liquid one after another.

It is a still further object of this invention to provide an improved hand powered dispenser for vaccines and other medicines including an arrangement for dispensing repeated equal quantities of liquid from a bottle or other original container with minimal loss of liquid.

Briefly, in carrying out the objects of this invention in one embodiment thereof, a hand held and hand powered liquid dispenser is provided which comprises a pump or cylinder body and a transverse handle usable with the pump actuation handle somewhat in the manner of a pistol grip. A fitting is provided on top of the body for receiving and retaining a bottle or other container of the liquid to be dispensed. A piercing tube or needle is mounted in the fitting to pass through the stopper or seal of the bottle and to provide a conducting passage between the bottle and the pump. An air inlet passage is provided for admitting air to the bottle to replace withdrawn liquid. A predetermined minimum amount of liquid may be trapped or retained in the dispenser regardless of the number of operations of the pump for dispensing doses of liquid from the bottle. A cannula or a hypodermic needle is detachably mounted on the discharge of the device for each operation and a quick removal device is provided which enables the operator to eject the used cannula immediately after use and to attach a new cannula for the next operation of the dispenser.

The features of novelty which characterize this invention are pointed out in the claims annexed to and forming a part of this specification. The invention itself, however, both as to its organization and manner of operation together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of a dispenser embodying the invention with a liquid supply bottle mounted thereon;

FIG. 2 is an enlarged side elevation of the dispenser of FIG. 1;

FIG. 3 is a rear elevation view of the dispenser;

FIG. 4 is a sectional elevation view of the dispenser taken along the line 4--4 of FIG. 3;

FIG. 5 is an enlarged sectional plan view taken along the line 5--5 of FIG. 4;

FIG. 6 is a sectional elevation view taken along the line 6--6 of FIG. 4;

FIG. 7 is a sectional elevation view taken along the line 7--7 of FIG. 4;

FIG. 8 is a top plan view of a cannula release slide of the dispenser of FIGS. 1-4;

FIG. 9 is an exploded view illustrating the parts of the dispenser in position for assembly; and

FIGS. 10 and 11 are sectional elevation views similar to FIG. 1 showing the liquid supply and discharge positions of a modified form of liquid source connection.

Referring now to the drawings the liquid dispenser illustrated in FIGS. 1, 2 and 3 comprises an elongated main body portion 10 having a transverse handle 11 cast integrally therewith and a pump actuating handle 12 positioned to be pressed toward the handle 11 by squeezing the grip by hand. A liquid source or supply illustrated as a bottle 14 is mounted on the body 10 by a fitting 15 secured on boss 16 cast as an integral part of the body 10. The handle 12 is biased outwardly away from the handle 11 by a compression spring 17 and upon squeezing together the handle 11 and the handle 12 liquid is discharged from the body 10 through a check valve 19 of the so-called "duck-bill" type and mounted in a threaded discharge fitting 18 sealed by a gasket 18a; the valve 19 prevents a reverse flow of liquid and the admission of air to the body 10. A cannula or other type of discharge nozzle, indicated at 20, is secured on the fitting 18 by a long taper fit which may be a Luer slip. The cannula 20 may be ejected by pressing a slide 21 forward along the body 10 after actuating a trigger 22 which may be easily actuated by the back of one finger of the operator while holding the handle 11. This arrangement for quick release of the cannula facilitates the use of a successive different cannula for each one of a plurality of individuals under treatment. The slip fit enables the operator to place a new cannula on the fitting 18 after release of the used cannula and the release is such that it is not necessary for the operator to touch the used cannula.

The fitting 15 includes an easily actuated bottle attaching and release lock 23. This lock may be actuated by turning in either direction to release the bottle 14 from its seat in the fitting 15 and to lock the bottle in place. Actuation of the lock presses the seal of the bottle against a sealing ring in a manner to be described below.

The internal structural features of the dispenser of this invention are illustrated in FIGS. 4 through 7. The body 10 as illustrated in FIG. 4 is formed to provide a cylinder 24 the left hand end of which is closed except for communication with the fitting 18 through a discharge passage 25. A piston 26 is slidably mounted in the cylinder 24 and is sealed against the wall of the cylinder by a suitable seal illustrated as an O-ring 27. The piston is connected by a rod 28 to the actuating handle 12. The right hand end of the cylinder is closed by a threaded fitting 30 which includes a flange 31 seated on the end of the body 10 having an outwardly projecting boss 32 formed at the rear of the handle 11 on an enlarged right hand end portion of the body 10. The rod 28 is of hexagonal cross section and passes through the closure 30 and is retained in position to hold the handle 12 upright and in substantial alignment with the handle 11 by a stop plate 33 having a hub or boss 33a and a hexagonal passage slidably fitting the rod. Positioning tabs 34 and 35 extend outwardly from the top and bottom of the plate and engage grooves 36 and 37, respectively, formed in the boss 32 along a center line parallel to the axis of the handle 11. The tabs of the plate are smaller in width than the grooves 36 and 37 and afford limited rotation of the rod within an arc of about 30° (15° to either side). This allows the handle 12 to tilt slightly relative to the handle 11 and provide a comfortable grip for both right and left-handed users. The spring 17 urges the handle 12 outwardly and holds the piston 26 in a selected maximum volume position. The maximum volume is selected by locating a straight pin portion of a resilient clip 38, as shown in FIG. 6. The straight portion may be inserted in any one of a plurality of transverse holes. In FIG. 4 the pin 38 is shown in the far right hand one of the holes 40 and stops the piston 26 in its minimum setting. Positioning the pin in each of the other holes will provide for the discharge of a volume of liquid corresponding to the setting, and, if the clip is removed, a shoulder 41 on the piston acts as the final setting for the volume of the cylinder and is the setting for the maximum volume for which the pump may be used.

When the piston moves to the right it tends to compress air within the cylinder between the back of the piston and the closure at the end. The closure, however, is provided with ventilating passages because the fitting 30 when seated against the handle 11 in the boss 32 is spaced from the end of the right hand cylinder wall a distance sufficient to provide space around the plate 33 so that air may escape through this space into the space within the boss about the fitting 30 and thence out into the spaces provided by the slots 36 and 37 and to the atmosphere. A cylindrical center passage in the fitting 30 affords rotation of the fitting about the boss 33a so that the shaft 28 is free to rotate within the limited range determined by the clearances between the tabs 34 and 35 and the recesses in the boss 32. It will be observed that the pressure of the spring 17 against the pin 38 or against the shoulder 41, depending upon the position of the stop selected, holds the plate 33 against the fitting 30 so that a space is maintained between the plate and the end of the cylinder.

The structure of the fitting 15 comprises a main cylindrical block or base 43 which has been illustrated as having an enlarged opening in its lower end and as threadedly attached to external threads on the boss 16. Within the boss 16 a nipple 44 is provided which is tapered to fit a long tapered internal passage in a base 45 of a needle or piercing tube 46 which is securely attached by a press fit or otherwise securely mounted in the base 45. The internal passage of the base 45 as indicated at 47 fits over the nipple 44 and extends sufficiently far into the base to provide a seat for a check valve 48 which is of flexible material and is of the so-called "duck bill" type. In the position illustrated in FIG. 4 this check valve allows flow downardly by separating the engaging lips of the valve but prevents return of fluid under pressure from below the valve. When the block 43 is screwed down onto the boss 16 an annular shoulder 50 thereon engages a conical upper wall 51 of the base 45 and the pressure applied when the base is seated on the nipple maintains an annular seal about the conical wall 51. In this manner the space between the base 45 and the interior walls of the boss 16 and base 43 is sealed at both ends against the admission of fluids. The seal provided by the conical wall 51 also separates the passage through the base 43 so that the upper portion of the passage indicated at 52, is sealed from the lower portion about the base 45.

When a bottle 14 is placed in the fitting 15 the collar 23 is turned to urge the cam followers or plungers 53 and 54 inwardly to engage the upper edge of the neck flange of the bottle. The plungers 53 and 54 have downwardly facing surfaces 55 and 56, respectively, which, upon inward movement under pressure of the cam surfaces on the collar 23, press the bottle downwardly so that the face of the resilient stopper or seal in the top of the bottle is urged against an upstanding annular ring 57 concentric with the passage 52 in the block 43. The upper portion 52 of the passage is thus sealed off both at top and bottom. The construction of the camming device is shown in enlarged detail in FIG. 5. In the full line portion of this figure, the plungers 53 and 54 are shown in their bottle engaging positions; the dotted lines illustrate the retracted positions of the cams wherein the plungers have been moved outwardly by springs 58 and 59. The plungers 53 and 54 extend through and slide in bearing openings 61 and 62, respectively, extending through the block 43. The block 43 is formed to provide a cylindrical cup 63 in its upper end for receiving the neck of the bottle 14. This cup is formed by an annular upward extension of the block 43 which terminates in an enlarged portion 64 having an outwardly extending flange 65 at its top. The openings 61 and 62 for the plungers 53 and 54 are provided in the enlarged portion 64. These openings are enlarged outwardly as indicated at 66 and 67, respectively, to provide retaining seats for the springs 58 and 59. The outer ends of the plungers are provided with relatively thin flat laterally extending rectangular feet or cam engaging portions 68 and 69, respectively, which ride on internal cam surfaces of the locking collar 23.

The locking collar 23 as shown in FIG. 4 comprises a lower annular portion 71 in sliding engagement with the body 43 and which is enlarged above the portion 71 to provide an annular seat 72 about which are formed the cam surfaces. The collar 23 is retained between the flange 65 and a detachable split ring 73 carried in an annular groove in the body 43. During the assembly of the fitting 15 the collar 23 is slipped over the lower end of the base 43 and then the split ring 73 is snapped into the groove to retain the collar in place.

The cam followers or plungers 53 and 54 are pressed against the internal cam surfaces of the collar as shown in FIG. 5, the rectangular feet 68 and 69 being urged against the cam surfaces and being bent somewhat circumferentially of the cam surface by the pressure of the cams and springs. The cam surfaces are arcuate and comprise a pair of diametrically opposite surfaces 74 and 75 which are concentric with the block 43 and a second pair of surfaces 76 and 77 extending outwardly from the ends of the surfaces 74 and 75 and which are of a substantially shorter radius. The pairs of opposite cams are thus symmetrical about each of two axes at 90° to one another. When the counter 23 is turned 90° in either direction from its position indicated in full lines in FIG. 5, the surfaces 76 and 77 will be opposite the respective ones of the plungers 53 and 54 and the plungers will move outwardly to their dotted line positions so that their inner ends no longer extend into the cylindrical cup 63 within the wall 64. The bottle can now be removed and replaced by a fresh bottle.

When a bottle 14 is positioned on the fitting 15 its closure indicated as comprising a stopper of rubber or other suitable material 78 and a metal collar 79 lies in engagement with the bottom of the cup 63 and the ring 57 engages the stopper 78 about the seal piercing tube 46. When the collar 23 is rotated to move the plungers 53 and 54 inwardly toward the neck of the bottle the sloping surfaces 55 and 56 of the plungers engage the stopper closure element 79 which extends around the flange of the bottle and presses the bottle downwardly so that the seal 78 is pressed into firm engagement with the ring 57 and seals the chamber 52 from the atmosphere.

Air is admitted to the chamber 52 through an inlet passage 81 through a duck bill valve 82 which prevents the return of air from the chamber 52 through the outlet 81. When the pump handle 12 is released after discharging liquid through the passage 25 it is moved to the right by the spring 17 and draws liquid downwardly through the tube 46 and check valve 48 and thus removes another charge of liquid from the bottle 14. In order to prevent the reduction of pressure in the bottle 14 and a tendency of the liquid not to flow outwardly therefrom air is admitted to the bottle through a passage in a small tube 83 which, as illustrated, is a straight tube extending along the tube 46 and terminating near the top thereof. Both the tubes are tapered to provide seal piercing points and the points lie adjacent one another at the tops of the tubes. It has been found that this arrangement of the liquid discharge and air inlet tubes effectively prevents the entrainment of air in the liquid flowing downwardly toward and into the tube 46. The bubbles coming from the tube 83 tend to rise immediately to the right as viewed in FIG. 4 and the liquid flows downwardly into the tube 46 without drawing the bubbles into this downward flow.

For some applications of the dispenser of this invention it may be desirable to employ a collapsible container instead of the rigid bottle 14 and to allow the container to collapse without having to admit air thereto; for this purpose the air tube 83 may be omitted in applications where for any reason the presence of air from the atmosphere might deteriorate the quality of the liquid contained in the bottle and make it unusable. The dispenser of this invention is suitable for use in the treatment of human patients and the arrangement for utilizing a collapsible container and preventing the admission of air to the vaccine or other liquid may be particularly desirable or required for this use particularly when the treatment involves the use of a hypodermic needle.

The structural details of the various parts and components of the dispenser are illustrated further in FIGS. 8 and 9, FIG. 9 being an exploded view of the details of construction of the slide 21 for ejecting a used discharge tube or cannula as shown in FIGS. 8 and 9. The slide 21 is preferably molded from synthetic plastic and comprises an elongated member open at the top and of a configuration to fit closely about the forward end of the body 10. The front end of the slide is closed by an upright wall 84 which is provided with an opening 85 through which a reduced diameter sleeve 86 on the fitting 18 can project. When the tube portion or nipple 86 projects through the opening 85 a cannula 20 may be pressed into position thereon. The slide is provided with longitudinal projections 87 extending along the top rear edges of the wall of the slide and which fit into grooves 88, one on each side of the body 10 directly under the boss 16. The projections 87 are shorter then the grooves 88 so that the slide 21 may be moved back and forth while the projections are in the slots and to the extent permitted by the ends of the slots which act as stops. The slide may be biased forwardly by a spring 90 which is compressed when a cannula is fitted over the nipple 86 and pressed into place against the front end of the slide. When the cannula is pressed into place over the nipple 86 a sear or catch 91 engages a cross slot 92 formed in the bottom of the body 10 below the rear ends of the slots 88. The catch 91 is mounted on a flexible tongue 93 which carries the trigger 22 and biases it upwardly or inwardly of the slide, and is securely welded or otherwise bonded to the forward end of the bottom of the slide 21, attaching lugs or rivets 94 being illustrated for this purpose. The trigger 22 extends downwardly from the flexible tongue 93 and when the trigger is pressed forwardly it bends the tongue downwardly and releases the catch 91 from the notch 92 whereupon the slide 21 moves forwardly and detaches the cannula. The spring 90 is not necessary to assure forward movement of the slide 21 because the pressure of the operator's finger against the trigger 22 will in most applications be sufficient to detach and release the cannula. The trigger 22 is in a position for quick use by the operator holding the dispenser in his hand and may direct the used cannula into a waste basket or other container so that it is not necessary to touch it. The operator may then put a new cannula on the device and proceed with the next use of the dispenser. Thus a large number of individuals may be treated one at a time each with a clean cannula.

For some uses of the dispenser it may be desirable to provide a larger volume of treating liquid than may be conveniently provided in a bottle attached to the dispenser. For such applications, the device illustrated in FIGS. 10 and 11 may be employed instead of the fitting 15. This device comprises a cap or closure 95 which is screwed onto the boss 16 and is provided with an inlet nipple 96 to which a supply conduit 97 may be attached. The cap 95 is provided with a check valve comprising a flexible disc 98 of synthetic plastic or other suitable material which is provided with a plurality of holes 100 therethrough in the portion thereof radially outside an annular shoulder 101 formed on the inner top wall of the cap 95 about the passage within the nipple 96. FIG. 10 illustrates the intake position of the valve wherein the drawing of fluid into the cylinder 24 has pulled the valve downwardly to permit flow of liquid through the holes 100. When the piston is moved forward toward the left as viewed in FIGS. 10 and 11 liquid is forced out the discharge passage 25 and also up into the chamber within the boss 16, the valve disc 98 is thereby forced upwardly so that the inner portion thereof is pressed against the annular ring 101 and prevents the passage of liquid back into the supply conduit. This supply conduit may be connected to a suitable source such as a bottle of liquid which may be placed on the ground or on a convenient support near the operator.

In the operation of the dispenser of this invention standard sizes of bottles, such as the bottle 14 may be employed and the collar 23 is made of sufficient size to except a range of sizes of these bottles. The necks of the bottles are of the same size and all fit in the cup 63 and are held by the plungers 53 and 54. A minimum loss of liquid is encountered during the course of use of the dispenser, a minor loss being due to some leakage of liquid into the passage 52 in the block 43. When starting the operation of the dispenser with a new bottle placed in the cup 63 and with the piercing tube 46 extending through the stopper 78 and into communication with the contents of the bottle a certain amount of air may be trapped in the passages of the dispenser. This air may be removed by operation of the pump with the discharge end tipped upwardly while the needle is maintained below the surface of liquid in the bottle 14. The initial pumping can thus remove all air so that the dispenser is ready for use. This initial loading involves some further minor loss of liquid. During operation the dispenser is held with the bottle upright and a preset dose is discharged through the passage 25 and the cannula or other discharge nozzle secured on the fitting 18. The volume to be discharged is determined by placing the pin 38 in a selected one of the holes 40 or by taking the clip 38 out and allowing the piston to move the full distance of the chamber until the shoulder 41 strikes the plate 33. Access to the clip 38 and the holes 40 is had by removing the closure plug 30 and drawing the handle 12 outwardly to expose the holes as required. After the selected hole position has been determined and the clip inserted therein, the closure 30 is returned to the position illustrated in FIG. 4 with the plate 33 in position and the device is ready for operation at the selected capacity. The dosage to be administered by the dispenser is thus determined and is not changeable except by removing the closure 30. Thus unintentional or inadvertent changing of the dose to be discharged is eliminated.

Certain vaccines, by way of example, are supplied in vacuum bottles like the bottle 14 and are the lyophilized vaccines wherein the solids of the vaccine have been dried by freeze drying and then placed in the bottle under vacuum. To use these vaccines a bottle of sterile water or other required liquid is provided in a sealed bottle such as the bottle 14. The liquid dispenser of this invention facilitates the charging of the vacuum bottle with the liquid to produce the vaccine to be used. For this purpose a bottle of water is mounted on the fitting 15 and a standard hypodermic needle placed on the fitting 18. Air is then removed from the dispenser by pumping so that water fills the working passages thereof. The hypodermic needle is then inserted through the seal of the dried vaccine and water is drawn into the vaccine bottle because of the different in pressures between the bottles. The delivery of the full quantity of water to the vaccine bottle may be facilitated by utilizing the pump of the dispenser and full discharge of the water into the vaccine bottle may thus be effected more easily. The vaccine bottle is then ready for use on the dispenser.

The base 45 of the needle 46 is made with a larger tapered passage than the corresponding passage of the standard hypodermic needle. In view of this difference in size it is not possible to attach a standard needle to the nipple 44 and thus the operator is assured that the needle attached to the dispensing unit will be a needle 46 and include the check valve 48 and prevent the discharge of liquid upwardly through the needle when mounted on the nipple 44. The base for a hypodermic needle provided on the fitting 18 is of standard dimensions and will accept the standard needle.

It will be apparent from the foregoing that the dispenser of this invention is useful in a wide range of applications and facilitates the treatment of a large number of individuals in a substantially reduced period of time. To further facilitate the use of the dispenser with minimum likelihood of contact, for example, of one individual with a cannula or part of a dispenser which has contacted another individual. The cannula 20 may be provided with a circular disc or shield 102 which may be used as a stop member in certain applications, for example, to limit the movement of the cannula into the nostrial of an animal. Thus, the likelihood of the animal's nostril coming into engagement with any part of the dispenser is minimized and when the used cannula is ejected the new cannula for the next animal can be inserted without likelihood of contacting any part which has contacted another animal. The dispenser of this invention may readily be cleaned and sterilized by autoclaving.

While this invention has been described in connection with a particular embodiment thereof, various modifications will occur to those skilled in the art. Therefore, it is not desired that the invention be limited to the specific details of the disclosed device and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.