A variety of different types of caps are commonly used for closing openings in containers, some of which are replaceably removable such as screw tops, and others of which clamp the top of the container and are damaged during removal so as to prevent their re-attachment to the container. Caps are also used in certain applications which have an internal aperture which is a close tolerance fit with the external surface of the container in the region of the opening and slidably engage thereon, the frictional engagement between the inner surface of the aperture and the external surface of the container retaining the cap in place. The frictional engagement between the cap and the container in arrangements of this type has to be sufficient to ensure that the cap does not unintentionally drop off of the container, and hence to remove such a cap, the container must be retained, for example by the user grasping it in one hand, whilst the cap is firmly grasped in the other hand and pulled away from the container. Even then, a cap of this type can be difficult to remove from a container by the user if the container is smaller and/or smooth sided, such as a test-tube, making it difficult to firmly grasp in one hand, or if the user has low hand strength or is otherwise infirmed.

Furthermore, in laboratory applications, it is often necessary to place samples into a number of such test tubes by selecting a test tube, removing the cap therefrom, placing the sample into the tube and then replacing the cap before selecting the next test tube, and the-requirement to use one hand to hold the test tube and the other to grasp and remove the cap makes this process very time consuming since after the cap has been removed, the user must put it down and pick up the sample dispenser, and then pick up the cap again in order to replace it on the test tube at the end of the procedure.

According to a presently preferred embodiment of the present invention, there is provided a slide cap removal device comprising a body having opposed side and opposed top and bottom walls extending between a first open end and a second substantially closed end, an internal aperture extending from said open end towards said closed end, and a slot formed in the bottom wall such that the bottom wall forms a flange which extends along said side walls on either side of the slot and around said closed end, which slot extends from said open end towards said closed end substantially parallel to and which penetrates said bottom wall to communicate with said internal aperture, wherein, in use, a cap is engageable in said aperture through said open end of the device with the neck of the container extending though said slot, and, upon relative movement of the device axially away from the container, said flange engages the lower edge of the cap to retain it within said aperture whilst the neck of the container is retracted from the device through the slot in the bottom wall.

A slide cap removal device in accordance with the invention has the advantage that the device may be held in the palm of the hand with minimal effort and a capped container inserted into the internal aperture to remove the cap, whilst the fingers of said hand are left free to insert a sample into or remove a sample from the uncapped container. In this way, the sampling procedure is accelerated.

The width of the slot in the bottom wall of the device is sized to be larger than the width of the neck of the container so as to enable said neck to be withdrawn from and re-introduced into the device through said slot. At the same time, the slot is narrower than the outer width of the cap so that the flanges engage the lower edge of the cap upon the container being withdrawn from the device through said slot and hence retain the cap within the aperture, causing it to be slidably removed from the container. The cap may also then be re-attached to the container by simply re-inserting the neck of the container into the internal aperture of the device through the slot and into the cap, whereupon the container may be withdrawn from the device along the slot and through said open end with the cap in place.

The device of the present invention may be operated in a particularly effective manner if firmly mounted in place, for example on a workbench or the like. The user need not then use a hand to hold the device, but instead simply inserts the capped container into the open end of the anchored device and withdraws the same through the slot using a single hand, leaving the other hand free to carry out the sampling operation.

Preferable the said walls of the internal aperture of the device taper inwardly from the open end towards the closed end of the device such that the cap is a close tolerance fit with the aperture at said closed end. In this way, the frictional engagement between the said walls of the aperture at the closed end of the device and cap when it is fully inserted into the aperture operates to retain the cap within the device when removed from the cap and hence prevents the cap accidentally falling out of the aperture through said open end, for example if the device is not mounted or held level.

In an advantageous development of the invention, projections are provided on the flanges and ! or on the inner surfaces of the opposed side walls of the device which extend from said bottom wall partially towards said top wall, which are spaced from said closed end so as to define a capture region with said closed end within which a cap may engage, and which form a constriction in the aperture which the cap cannot pass through. The projections are, however, sized relative to the height of the aperture and the height of the cap so that the cap can pass over the projections and the constriction if located within the aperture proximate to the top wall of the device. In use, then, the neck of the container with cap attached can be moved along the slot with the neck fully inserted into the aperture so that the cap is proximate to the upper wall and hence can pass over the projections into the capture region defined between the projections and the closed end of the device. Upon retracting the neck of the container through the slot, the cap is pulled towards the flanges, causing it to engage behind the projections and hence to be captured within the device between the projections and the closed end of the device. In this way, the cap, when removed from the container, is always held in the same position, thereby facilitating realignment of the container with the cap when inserting the neck back into the device. When the neck of the container is re-inserted through the slot of the device, the frictional engagement between the neck and the cap lifts the cap out of the capture region and into abutment with the inner surface of the top wall, by which it is firmly pressed onto the container. In this position, the cap can again be moved over the constriction and the capped container can be moved along the aperture and removed through the open end of the device.

In a particularly preferred form of the invention, each projection is stepped at its end proximate to the closed end of the device so as to form a discontinuity in cross-section of the internal aperture when a cap is moved from the closed end towards the open end of the device, and is inclined downwards towards the open end of the device at its end which is pointed towards said open end so as to form a ramp surface which extends upwards from the associated flange in the direction away from the open end. In this way, as a cap travels along the aperture towards the closed end, it will be engaged by the ramp surfaces of the projections and the resulting camming action causes the cap to move towards said top wall and to pass over the constriction in the aperture. Each projection also preferably tapers laterally inwardly so as to merge smoothly into the associated side wall at said capture regions.

The projections are advantageously integrally formed with the side walls of the device and also with the flanges. However, they may alternatively be formed just on one or other of the side walls and the flanges.

In order that the invention may be well understood, there will now be described an embodiment thereof, given by way of example, reference being made to the accompanying drawings, in which: Figure 1 is a perspective view of a device according to the present invention ; Figure 2 is a sectional side view of the device of Figure 1; Figure 3 is a sectional top view of the device of Figure 1 ; Figure 4 is a top view of the device of Figure 1; and Figure 5 is an end view of the device of Figure 1.

Referring first to Figure 1 of the drawings, there is shown a slide cap removing device 1 having opposing sides walls 2,3 joined together along their top edges 2a, 3a by a top wall 4, along their bottom edges 2b, 3b by a bottom wall 10 and at a first end 5 of the device 1 by a curved end wall 6 which substantially closes said first end 5. In the illustrated embodiment, the top wall includes a longitudinal slot, but may also be formed without that slot. The second end 7 of the device 1 is open as shown in Figure 1 so as to allow access to an internal cavity 8 of the device defined between the side, top and bottom walls 2,3, 4,10, and is sized to allow a cap which, in use, is to be removed by the device to pass through the open end 7 of the device and along the cavity 8.

The bottom wall 10 has a slot 11 formed therein which extends from the open end 7 of the device axially along the bottom wall 10 towards the first closed end 5. The width of the slot is sufficient to allow the neck of a container whose cap is to be removed to pass through and along the slot 11 from the open end to the closed end of the device 1 with the cap attached whilst the cap is positioned in and moves along the cavity 8, whilst being narrow enough to prevent the cap from passing along or through the slot 11. The bottom wall 10 thereby forms a flange 12 which extends along either side of and around the closed end of the slot 11 against which the lower edge of the cap will engage when the container on which the cap is slidably mounted is withdrawn from the cavity 8 through the slot 11. In this way, the flange 12 prevents the cap from passing through the slot 11 and applies a reaction force to the cap which overcomes the frictional force holding the cap on the container and hence slidably removes the cap from the container. Similarly, the top wall 4 of the device 1 provides a stop to limit the upwards movement of the cap within the cavity 8, so that when the mouth of the container is re-inserted into the cavity 8 through the slot 11 in alignment with the cap located within the device, the cap will be pressed against the top wall 4 which provides a reaction force that overcomes the frictional force developed between the cap and the outer surface of the neck of the container and hence urges the cap back onto the container. A slot may also be formed in the top wall 4 to enable the location of a cap within the cavity 8 easily to be seen by a user.

Whilst such removal and re-attachment of the cap can be performed at any point along the device 1 as long as the cap is sufficiently supported by the flange 12, the device 1 also includes retaining means proximate to its closed end 5 which operate to hold the cap in position when it is removed from the container, thereby ensuring that the cap does not fall out of the device 1 once separated from the container and also facilitating realignment of the container with the cap through the slot 11 during re-capping of the container. These retaining means comprise a pair of projections 14 which are provided on the inner surface of each side wall 2,3 of the device in the region of the flange 12 and proximate to the close end 5. In the illustrated embodiment, the projections 14 are formed as part of the flange 12, but may also be formed separately thereof. The projections are axially aligned with each other and form a constriction in the width of the cavity 8 in the device 1 through which the cap cannot pass. The height of the cavity 8 as well as the position of the projections 14 is such, however, to allow the cap to pass over the top of the constriction into a capture region 15 of the cavity 8 defined between the constriction and the closed end wall 6 of the device. This capture region 15 is sized and shaped to complement the external size and shape of a cap with which the device is to be used such that the outer periphery of the cap is a close tolerance fit between the projections 14 and the end wall 6 of the device and hence the cap is securely held in the capture region 15 by the frictional engagement between the inner walls of the cavity and the projections 14 and the outer surface of the cap.

As is more clearly shown in Figure 2, each projection 14 is formed as a ramp having a downwardly inclining surface 14a facing the open end 7 of the device 1 and a substantially vertically extending surface 14b facing the closed end wall 6 of the device 6. In this way, as a cap moves along the cavity 8 from the open end towards the closed end wall 6, the ramped surfaces 14a of the projections 14 will operate to guide the cap over the constriction by development of a camming action between the inclined surface 14a and the cap in the event that the cap is not already positioned sufficiently high within the cavity to allow it to pass over the cavity 8. Once cap has passed the constriction and is engaged against the end wall 6 of the device, the container is withdrawn through the slot 11, which action initially pulls the cap into the capture region 15 of the cavity 8 where it is held between the vertical surfaces 14b of the projections 14 and the closed end wall 6. In order to facilitate the gripping of the cap and to assist in its positive location, said vertically extending surface 14b of each projection 14 preferably tapers laterally inwards towards its associated side wall 2,3 at the capture region 15 so as to merge smoothly into said side wall.

Once sampling of the container has been completed, the mouth of the container is re- inserted into the cavity 8 of the device 1 through the slot 12 at the closed end 5 where the cap is held. The engagement force applied by the user is sufficient to lift the cap out of the capture region 15 of the cavity and it is pressed against the top wall 4 whilst the mouth of the container is firmly engaged therein. In this raised position, the cap is free to move along the cavity towards the open end and over the constriction as the user slides the neck of the container along the slot 11, the cap passing out through the open end of the device 1.

In order to further facilitate the free movement of the cap along the cavity into and out of the capture region 15, the side walls 2,3 of the device taper inwards towards the closed end wall 6, as clearly shown in Figure 3, so that the width of the cavity decreases towards the capture region 15 to a dimension which is a close tolerance fit with the maximum outer dimension of the cap at the capture region. In this way, adequate clearance is provided between the cap and the walls of the chamber 8 to allow free movement of the cap along the device whilst ensuring that the cap is guided into a central position within the capture region 15 and is also frictionally engaged by the side walls 2,3 as well as by the end wall 6 and the rear face 14b of the projections 14 when engaged in the capture region, hence maximising the restraining for applied to the cap. It will also be noted that the chamber tapers inwardly from the top wall 4 to the bottom wall as shown in Figure 5, thereby further facilitating free movement of the cap along the cavity when it is positioned proximate to the top wall 4 whilst ensuring the cap is both central and properly engage by the side walls when engaged in the capture region 15.

Additionally projections may be provided on the inner surfaces of the sides 2,3 and end wall 6 of the device proximate to the bottom wall 10 as shown in Figure 1. These projections, which, in the illustrated embodiment are formed as taper darts which point towards the top wall, from a further restriction in the capture region 15 which ensures that a cap is firmly engaged when it is drawn into the capture region and hence finnly retained therein. It will, of course, be understood that the provision of such dart projections 16 in the capture region 15 might avoid the need for the cavity 8 to taper inwardly towards the bottom wall 10.

It will, of course, be understood that a number of variations to the invention may be made within the underlying concept. For example, the device may be provided with a plurality of longitudinally spaced pairs of projections, each pair being associated with a capture region of a different size, the capture regions being sorted into decreasing sizes as a cap is moved along the device towards the closed end. In this way, the device can be used with caps of a variety of different sizes, each cap size having associated projections and capture zone in which it engages and is secured upon removal from a container. In this arrangement, each capture zone may be terminated at its end proximate to the closed end 5 of the device by a constriction which prevents caps of a size associated therewith from travelling further along the device than said capture zone whilst caps of a smaller size can pass through the constriction and further along the cavity towards their associated capture region. The slot in the bottom wall may also, then, taper inwards towards the closed end of the device to reflect the smaller container size which would typically be associated with the smaller cap sizes, thereby ensuring that the flanges properly engage and operate to retain each cap within its associated capture region.