GB1583816A

GB1583816A - Pellet magazine

Info

Publication number: GB1583816A
Application number: GB1759878A
Authority: GB
Original assignee: Hundon Forge Ltd
Current assignee: Hundon Forge Ltd
Priority date: 1978-05-22
Filing date: 1978-05-22
Publication date: 1981-02-04

Description

(54) PELLET MAGAZINE (71) HUNDON FORGE LIMITED, a British Company whose registered address is Hundon Forge, Homefield Road, Haverhill, Suffolk do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention concerns magazine cartridges for containing drugs in pelleted form.

It is known from British Patent Specification No. 1370173 to provide pelleted drugs for insertion below the skin of animals and livestock and a gun is described in the aforementioned Specification for driving the pelleted drugs through the hollow interior of a hypodermic type needle extending from the gun.

In this known form of implanter (hereinafter referred to as an implanter of the type described) the pellets have been previously held captive in a cylindrical magazine cartridge adapted to be received in a housing at the front end of the handle assembly and a fresh charge of pellets has been made available after each insertion by circularly indexing the cylindrical cartridge by one step so as to align a fresh line of pellets in the magazine cartridge with the thrust pin and hollow needle.

Cylindrical magazine cartridges of this type are cumbersome and expensive and it is an object of the present invention to provide an improved magazine cartridge for drug implanters which may be used with either a modified form of drug implanter of the type described or in the implanter described in co-pending British Patent Application No. 1525841.

According to the present invention a magazine cartridge for housing pelleted drugs comprises a generally rectangular housing having formed therein a plurality of parallel equally spaced apart bores in which rows of pelleted drugs can be located, each of the bores including a restriction in its cross-sectional area sufficient to prevent the pelleted drugs from passing completely therethrough in one direction and an opening at its remote end through which the pellets can pass freely and a cap member retained on the housing and covering the openings through which the pellets will pass freely.

The cap member may include apertures through which the pellets can be pushed, which are aligned with the bores when the cap is fitted on the housing.

The cap member may include a sheet of foil such as metal foil or plastics sheet or similar sheet material which is stretched over and covers the apertures. The foil may be secured to the outer surface of the cap and is preferably sufficiently strong as to normally prevent pellets from falling therethrough but weak enough to allow it to be broken when pellets are forced forwards during an implanting action.

The end of the housing which is covered by the cap member is preferably formed with an increased cross-sectional thickness so that the housing has a T-section when viewed end on perpendicular to the lines of the bores and in line with the plane of the bores, the increased cross-sectional width producing two shoulders along at least the two longer edges of the housing and the cap member includes inwardly directed lips which will snap fit around the shoulders to retain the cap member in position.

By virtue of its width the cap member forms shoulders along at least two opposite sides of the housing.

Where it is important that the contents of the magazine cartridge are kept sterile, a shoulder is preferably formed around all four sides of the magazine cartridge at the end to which the cap is to be fitted and a lip is formed around all four internal edges of the cap member so as to provide a snapon airtight seal around the complete periphery of the cap member and a second sheet of foil or similar material may be secured over the opposite end of the housing to cover the openings of the bores at that end of the housing.

Whereas the body of the magazine cart ridge is preferably formed from a rigid plastics material, the cap member is preferably formed from a pliable but resilient plastics material to allow it to be snap-fitted around the shoulder around the end of the housing to which it is fitted.

In order to enable the magazine cartridge to be indexed through a passage in the implanter, the two opposite larger faces of the magazine cartridge housing may be formed with a plurality of similar parallel triangular cross-section indentations leaving parallel triangular cross-section abutments between the indentations. Typically the abutments coincide with and extend parallel to the axes of the bores and the vertices of the triangular indentations lie approximately half-way between adjoining parallel bores in the housing.

Preferably the apertures in the cap member include radially inwardly directed abutments which will normally prevent a pellet from falling therethrough but which, if the pellet is pushed from the rear, will not impede the progress of the pellet through the aperture.

The invention will now be described by way of example with reference to the accompanying drawings.

Figure 1 is a cross-section through a magazine cartridge constructed as an embodiment of the invention, Figure 2 is an end view in the direction of the arrow A of the assembly shown in Figure 1 with the cover partly cut away, Figure 3 is an end view of the assembly shown in Figure 1 in the direction of the arrow B, Figure 4 is a side view of an implanter which will receive magazine cartridges constructed in accordance with Figures 1 to 3, Figure 5 is an end view of the implanter of Figure 4, Figure 6 is a cross-section through the magazine-cartridge-containing device shown in Figure 5, Figure 7 is a similar view to Figure 6 with the indexing device in its maximum indexed position, Figure 8 is a cross-section through the magazine-cartridge-containing device such as shown in Figures 5 to 7 viewed in the direction of the arrows BB in Figure 6, and Figure 9 is a similar cross-section to that shown in Figure 8 of the same device but this time viewed in the direction of the arrows CC in Figure 6.

The magazine cartridge assembly shown in the drawings comprises a generally flat housing 10 the opposite side faces of which are formed with a plurality of equally spaced apart triangular cross-section indentations designated 12 on the one side and 14 on the other. The indentations 12 and 14 allow the magazine cartridge to be indexed through a passage in a drug implanter. Reference is directed to British Patent Specification 1370173 and to Figures 4 onwards in the present application for details of drug implanters.

As shown in Figure 1, the housing 10 includes a plurality of parallel bores one of which is generally designated by reference numeral 16. Each of the bores is similar and each is divided into three basic sections.

To the right hand end of each bore as shown in Figure 1, the diameter increases towards the rear right hand edge of the magazine cartridge 18 (hereinafter referred to as cartridge) to form a flared entrance to the bore to facilitate axially locating a pin (not shown) which is moved in a forward direction from the drug implanter to pass through the passage and push the pelleted drugs therethrough. The diameter of the bore in the flared section which is designated 20 is reduced to less than the diameter of the pellets which are to be contained within the remaining sections of the bore but the diameter is not reduced so much that the pin (not shown) from the implanter cannot pass therethrough.

Referring again to Figure 1 three pellets generally designated 22 are contained in the remaining sections of the bores and by virtue of a shoulder 24 formed between the flared section 20 and the next section 26 of the bore the pellets cannot pass to the right of the shoulder 24 as shown in Figure 1.

The exit left hand end of each bore is countersunk in the region designated 28 and as will hereinafter be described in more detail, the left hand end of the housing 10 (as shown in Figure 1) is covered by a snapson cap 30 which has apertures therein corresponding to the positions of the bores 16 in the housing one such aperture being designated by reference numeral 32 in Figure 2. The aperture includes four radially inwardly directed abutments or lips one of which is designated by reference numeral 34. The radial inward extent of the abutments 34 is such as to just prevent the pellets from passing through the aper- tures 32 unless they are pushed and they serve to hold the pellets captive in the bores until they are to be ejected through the implanter needle.

The cap member 30 fits completely over the exit left hand end as shown in Figure 1 of the housing 10 and is a snap fit on the increased cross-section of the housing 10 which is shown in dotted outline in Figure 3 and is designated by reference numeral 36. The enlarged cross-section forms a T-section or hammerhead at that end on the two larger faces of the housing 10 and the cap member 30 includes an internal recess designed to accommodate the head 36 and internal lips shown in dotted outline at 38 and 40 which engage the underside of the head 36 on opposite sides of the housing 10 to hold the cap member 30 in place.

The cap member is therefore preferably formed from a soft pliable plastics material to allow it to be snap-fitted around the head 36 whilst the cartridge housing 10 and at least the head section 36 are more conveniently formed from a less pliable more hard setting plastics material.

An improved fit may be provided between the cap 30 and the member 10 by providing an oversize head edge region so as to provide an overhanging shoulder or edge on all four sides of the housing 10 and by providing an appropriately increased hollow interior within the cap 30 and appropriate lips on all four edges of the opening in the end of the cap member which fits over the housing end so that a good seal can be formed between the cap member 30 and the housing 10. By using this full seal around all four sides, the interior of the bores 16 can be sealed hermetically by fixing a sheet of foil over the outer surface of the cap member 30 and over the opposite end 18 of the housing 10 so as to cover the holes therein.

Whilst the foil may be left in place, it is preferably removed before the cartridge is inserted into the cartridge-receiving device in the implanter so that there is no possibility of small pieces of foil being trapped with the pellets and implanted into the animal below the skin.

The oversize head and cap member 30 provides a reliable device for ensuring that the cartridge can only be inserted into the cartridge-receiving section of the implanter with the exit ends facing the rear end of the needle and the flared ends 20 of the bores 16 facing the thrust end of the pin (to be described) used for ejecting the pellets.

Turning now to Figures 4 to 9, reference is made to the prior published Patent Specification 1370173 for details of the construction and operation of the handle section 40 of the implanter shown in Figures 4 and 5.

The front end of the implanter generally designated 42 constitutes a generally flat housing substantially similar in width to the width of the implanter handle section 40 and includes on one side a slide member 44 which can be depressed to index a flat cartridge of the type shown in Figures 1 to 3 by one division at a time through the housing.

Figures 6 and 7 illustrate how the indexing mechanism works.

The housing 42 includes a parallel-sided passage 46 the walls of which are recessed at 48 to receive spring 50 and at 52 to receive a second spring member 54 which is attached to the slide member 44.

The lower ends of the two springs 50 and 54 are curved inwardly and the end 54 engages in the indentations designated 12 on the one side of the cartridge 10.

The sliding member 44 is received in a slot 60 formed in the wall of the device 42 and a spring 62 urges the sliding member 44 in an upward direction as shown in Figure 6.

As shown in Figure 7 the sliding member can be pushed in a downward direction compressing the spring 62 and moving the resilient spring member 54 in a generally downward and inward path so that the lower end which engages one of the indentations 12 pushes the flat package cartridge 46 in a generally sideways and downward direction.

The spring 50 on the opposite side of the passage flexes against the sideways movement of the flat cartridge 10 to accommodate the sideways movement and the internal spacing between the opposite parallel sides of the passage 46 is such as to allow the indentations 12 to completely disengage from a complementary pair of indentations denoted by reference numerals 64 and 66 (see Figure 7) so as to allow the cartridge 10 to move in a downward direction to the extent determined by the movement of the sliding member 44 and spring 46 connected thereto. The distance through which the member 44 can move in a downward direction is limited so as to be just sufficient to cause the cartridge 10 to index by a distance equal to the width of one indentation so that when the member 44 is released and it returns to its original position, the spring 50 will flex in the inward direction and push the now lowered cartridge 10 into engagement with the abutments 64 and 66 which may cause further continued downward movement of the cartridge 10 until the indentations 12 register correctly with the abutments 62 and 64, when the cartridge 10 will have assumed its new indexed position within the housing 42.

The spacing between adjacent peaks between the indentations 12, 14 and the spacing between adjacent bores 16 is made equal so that by moving the cartridge 10 in a downward direction by an amount equal to the spacing between the peaks of adjoining indentations so the member will have been indexed by a distance equal to the spacing between two of the axial bores 16.

Referring again to Figure 4 the housing 42 is there shown mounted on the front end of an implanter handle assembly and the slide member 44 can be clearly seen situated between two parallel side cheeks 68 and 70. From the front end of the housing 42 extends a hollow needle 72 through which the pellets can pass.

Referring now to Figures 8 and 9 it will be seen that the hollow interior of the needle 72 aligns with an aperture 74 in the opposite end of the housing 42 to which the actuating pin (not shown) can protrude and the position of the two abutments 64 and 66 is chosen so as to cause the flat cartridge 10 having indentations along both sides to be accurately positioned along the length of the passage 46 so that when the abutments 66 and 64 are received in indentations 46, one of the bores 16 aligns with the aperture 74 and the axis of the hollow needle 72 so that when the pin (not shown) is pushed through the aperture 74 it can enter the bore in the cartridge 10 and push the pellets contained therein out through the hollow needle 72.

Also shown in the cross-section of Figure 8 is the recess 52 within which the spring member 54 (not shown in Figure 8) is received and the inner section of the sliding member 44, generally designated 76, to which the spring member (not shown) is attached. The recess 52 extends into the region of the abutments 64 and 66 so as to allow the spring 54 to extend between the abutments 64 and 66 as shown in Figure 6.

Figure 9 is an opposite cross-section through the housing 42 and illustrates the other recess 48 within which the opposite spring 50 is received. In the lower end of the recess 48 an additional recess is formed designated by reference numeral 78 into which the lower end of the spring 50 can be pushed well clear of the abutments between indentations 14 on the right hand side of the cartridge 10.

WHAT WE CLAIM IS: 1. A magazine cartridge for housing pelleted drugs comprising a generally rectangular housing having formed therein a plurality of parallel equally spaced apart bores in which rows of pelleted drugs can be located, each of the bores including a restriction in its cross-sectional area sufficient to prevent the pelleted drugs from passing completely therethrough in one direction and an opening at its remote end through which the pellets can pass freely and a cap member retained on the housing and covering the openings through which the pellets will pass freely.

2. A cartridge as claimed in claim 1 in which the cap member includes apertures, through which the pellets can be pushed, in alignment with the bores.

3. A cartridge as claimed in claim 1 or 2 in which sheet material is stretched over and covers the apertures.

4. A cartridge as claimed in claim 3 in which the sheet material is secured to the outer surface of the cap member.

5. A cartridge as claimed in claim 3 or 4 in which the sheet material is sufficiently strong as to normally prevent pellets from falling therethrough but weak enough to allow it to be broken when pellets are forced forwards during an implanting action.

6. A cartridge as claimed in any of claims 3 to 5 in which the sheet material is metal foil or plastics sheet.

7. A cartridge as claimed in any one of the preceding claims 1 to 6 in which the end of the housing which is covered by the cap member is formed with increased crosssectional thickness so that the housing has a T-section when viewed end on perpendicular to the lines of the bores and in line with the plane of the bores, the increased cross-sectional width producing two shoulders along at least the two longer edges of the housing, and the cap member includes inwardly directed lips which will snap around the shoulders to retain the cap member in position.

8. A cartridge as claimed in any one of the preceding claims in which the cap member forms shoulders along at least two opposite sides of the housing.

9. A cartridge as claimed in claim 7 or 8 in which a shoulder is formed around all four sides of the cartridge at the end to which the cap member is to be fitted and a lip is formed around all four internal edges of the cap member so as to provide a snap-on airtight seal around the complete periphery of the cap member and a second sheet of sheet material is secured over the opposite end of the housing to cover the openings of the bores at that end of the housing.

10. A cartridge as claimed in any one of the preceding claims in which the body of the cartridge is formed from a rigid plastics material and the cap member is formed from a pliable but resilient plastics material to allow it to be snap-fitted around the shoulder around the end of the housing to which it is fitted.

11. A cartridge as claimed in any one of the preceding claims in which the two opposite larger faces of the cartridge are formed with a plurality of similar parallel, triangular cross-section, indentations leaving parallel triangular cross-section abutments between the indentations, to engage corresponding triangular cross-section abutments in a wall of a passage in the implanter into which the cartridge is fitted, to assist in advancing it through the passage.

12. A cartridge as claimed in any one of the preceding claims in which the apertures in the cap member include radially

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. situated between two parallel side cheeks 68 and 70. From the front end of the housing 42 extends a hollow needle 72 through which the pellets can pass. Referring now to Figures 8 and 9 it will be seen that the hollow interior of the needle 72 aligns with an aperture 74 in the opposite end of the housing 42 to which the actuating pin (not shown) can protrude and the position of the two abutments 64 and 66 is chosen so as to cause the flat cartridge 10 having indentations along both sides to be accurately positioned along the length of the passage 46 so that when the abutments 66 and 64 are received in indentations 46, one of the bores 16 aligns with the aperture 74 and the axis of the hollow needle 72 so that when the pin (not shown) is pushed through the aperture 74 it can enter the bore in the cartridge 10 and push the pellets contained therein out through the hollow needle 72. Also shown in the cross-section of Figure 8 is the recess 52 within which the spring member 54 (not shown in Figure 8) is received and the inner section of the sliding member 44, generally designated 76, to which the spring member (not shown) is attached. The recess 52 extends into the region of the abutments 64 and 66 so as to allow the spring 54 to extend between the abutments 64 and 66 as shown in Figure 6. Figure 9 is an opposite cross-section through the housing 42 and illustrates the other recess 48 within which the opposite spring 50 is received. In the lower end of the recess 48 an additional recess is formed designated by reference numeral 78 into which the lower end of the spring 50 can be pushed well clear of the abutments between indentations 14 on the right hand side of the cartridge 10. WHAT WE CLAIM IS:

1. A magazine cartridge for housing pelleted drugs comprising a generally rectangular housing having formed therein a plurality of parallel equally spaced apart bores in which rows of pelleted drugs can be located, each of the bores including a restriction in its cross-sectional area sufficient to prevent the pelleted drugs from passing completely therethrough in one direction and an opening at its remote end through which the pellets can pass freely and a cap member retained on the housing and covering the openings through which the pellets will pass freely.

inwardly directed abutments which will normally prevent a pellet from falling therethrough but which, if the pellet is pushed from the rear, will not impede the progress of the pellet through the aperture.

13. A magazine cartridge for a drug implanter constructed and arranged substantially as herein described with reference to and as illustrated in the accompanying drawings.