Pressure equalising piercing device for jars having a screw-top closure

Abstract

A pressure equalising device (10) which has a squat shape and which has three positions which are a first unlocked and retracted position, a second locked and retracted position, and a third unlocked and extended position wherein the device comprises a spike (14) for piercing a container, a biasing member (12) to bias the device into the first position from the third position, an upper body (20) which supports the spike and which has a locking formation (28), and a lower body (40); wherein the device has a twist lock such that the device can be rotated to and from its first and second positions; wherein the twist lock comprises a slot (52) in the lower body which is positioned to receive the locking formation (28) to immobilise the upper body (20) in relation to the lower body (40); the invention provides an ergonomically acceptable and safe way to reduce the torque force required to open the typical jar to less that 2 Nm by equalising the pressures inside and outside the jar.

Claims

1. A pressure equalising device which has a squat shape and which has three positions which are a first unlocked and retracted position, a second locked and retracted position, and a third unlocked and extended position wherein the device comprises a spike for piercing a container to increase its internal pressure, a biasing member to bias the device into the first position from the third position, an upper body which supports the spike and which has a locking formation, and a lower body; wherein the device has a twist lock such that the device can be rotated to and from its first and second positions; wherein the twist lock comprises a slot in the lower body which is positioned to receive the locking formation to immobilise the upper body in relation to the lower body.

2. The device as defined in claim 1 wherein the spike is withdrawn into the lower body in the first or second positions.

3. The device as defined in claim 1 wherein the device has a cylindrical shape.

4. The device as defined in claim 1 which has a squat shape wherein the ratio of its diameter to its height is from 1.2:1 to 1:1.2.

5. The device as defined in claim 1 wherein the upper body has an upper body wall which has an upper body wall rim along its lower edge which forms an opposing pair of notches for indicating whether the pressure equalising device is in its second locked position or first/third unlocked position.

6. The device as defined in claim 1 wherein the locking formation is in the form of a horizontal inwardly-extending arcuate ridge.

7. The device as defined in claim 1 wherein the upper body has a spike support with a plurality of spike support ribs to guide and support the biasing member.

8. The device as defined in claim 1 wherein the lower body has a base having a base peripheral ridge for engaging with a container to be pierced.

9. The device as defined in claim 1 wherein the base has a dome-shaped formation which forms a base aperture through which the spike extends in the third position.

10. The device as defined in claim 1 wherein the base has an outer wall which forms an outer wall cut out in which is provided a lower body clip for engaging the locking formation.

11. The device as defined in claim 10 wherein the lower body clip has a lower body clip hook which is shaped to engage with the locking formation.

12. The device as defined in claim 1 wherein the lower body has an outer wall which forms an outer wall cut out and the slot is formed in the outer wall at an edge of the outer wall cut out.

13. The device as defined in claim 1 wherein the slot has a narrow slot entrance and a slot ramp to reduce the risk of the device being moved from its second locked position to its first unlocked position accidentally.

14. A pressure equalising device which has a squat shape and which has three positions which are a first unlocked and retracted position, a second locked and retracted position, and a third unlocked and extended position wherein the device comprises a spike for piercing a container to increase its internal pressure, a biasing member to bias the device into the first position from the third position, an upper body which supports the spike and which has a locking formation, and a lower body; wherein the device has a twist lock such that the device can be rotated to and from its first and second positions; wherein the twist lock comprises a slot in the lower body which is positioned to receive the locking formation to immobilise the upper body in relation to the lower body; wherein lower body has an outer wall; wherein the outer wall forms an outer wall cut out in which is provided a lower body clip for engaging the locking formation; wherein the slot has a slot entrance which has an upper end which is arranged to be at substantially the same level as the lower body clip.

15. The device as defined in claim 14 wherein the locking formation is in the form of a horizontal inwardly-extending arcuate ridge.

16. The device as defined in claim 14 wherein the upper body has a spike support with a plurality of spike support ribs to guide and support the biasing member.

17. The device as defined in claim 14 wherein the lower body has a base having a base peripheral ridge for engaging with a container to be pierced.

18. The device as defined in claim 14 wherein the base has a dome-shaped formation which forms a base aperture through which the spike extends in the third position.

19. The device as defined in claim 14 wherein the lower body clip has a lower body clip hook which is shaped to engage with the locking formation.

20. The device as defined in claim 14 wherein the slot has a narrow slot entrance and a slot ramp to reduce the risk of the device being moved from its second locked position to its first unlocked position accidentally.

Description

[0022] The invention will now be illustrated with reference to the following Figures of the accompanying drawings which are not intended to limit the scope of the claimed invention:

[0023] FIG. 1 shows a schematic exploded perspective view of the pressure equalising device according to the invention;

[0024] FIG. 2 shows a schematic perspective view of a lower body of the pressure equalising device shown in FIG. 1;

[0025] FIG. 3 shows a schematic vertical cross-sectional view of the lower body of the pressure equalising device shown in FIG. 2;

[0026] FIG. 4 shows a schematic perspective view of an inverted upper body of the pressure equalising device shown in FIG. 1; and

[0027] FIG. 5 shows a schematic vertical cross-sectional view of the upper body of the pressure equalising device shown in FIG. 4.

[0028] A pressure equalising device according to the invention is indicated generally at 10 on FIG. 1 of the accompanying drawings. Pressure equalising device 10 has a cylindrical squat shape with a diameter which is approximately the same as its height. Pressure equalising device 10 has three positions which are a first unlocked and retracted position, a second locked and retracted position, and a third unlocked and extended position. Thus, the pressure equalising device 10 may be locked in a retracted position for safety. Pressure equalising device 10 comprises a biasing member 12 to bias the device 10 into its first position from the third position, a spike 14 which is extended in the third position, an upper body 20 which supports the spike, and a lower body 40 which may be locked relative to the upper body 20 in the second position. The device 10 may be formed by moulding a resilient plastics material. Biasing member 12 may be in the form of a spring.

[0029] Upper body 20 is illustrated in more detail in FIGS. 4 and 5. Upper body 20 has an upper body wall 22 which forms an external surface for the device 10, an upper body grip 26 for operating the device 10 by moving it from its first position to its third position, and a spike support 30. Upper body wall 22 has an upper body wall rim 23 along its lower edge which forms an opposing pair of notches 24 for indicating whether the pressure equalising device 10 is in a locked or unlocked position. On an inner surface of upper body wall 22 a pair of opposing upper body wall locking formations 28 are formed. Upper body wall locking formations 28 are in the form of horizontal inwardly-extending arcuate ridges which have a rectangular cross-section. The upper body wall locking formations 28 are arranged at a height from the upper body wall rim 23. Spike support 30 has four spike support ribs 32 which are arranged in the form of a cross around the support 30 and which guide and support the biasing member 12. Spike support 30 forms a vertical spike aperture 34 in which spike 14 may be fixed by gluing. Alternatively, spike 14 may be fixed by being bonded to the vertical spike aperture 34 during the formation of the upper body 20 by plastics moulding.

[0030] Lower body 40 is illustrated in more detail in FIGS. 2 and 3. It has a base indicated at 41, an inner wall 60 and an outer wall 50 which has a first height above base 41. Inner wall 60 has a cylindrical shape such that its outer surface supports biasing member 12. Inner wall 60 receives spike support 30.

[0031] Base 41 has a base peripheral ridge 48, a base step 44, a dome-shaped formation 42, and a base aperture 34. The base peripheral ridge 48 is for engaging with the lid of the container to be pierced. The base peripheral ridge 48 may be formed from a resilient material to reduce the risk of the device 10 slipping on the lid. The base step 44 forms a support for the outer wall 50 and connects the base peripheral ridge 48 to the dome-shaped formation 42. The dome-shaped formation 42 forms a support for inner wall 60 and forms the base aperture 34 through which the spike 14 extends when the device 10 is in its third position when it is operated to pierce the lid of a container.

[0032] The outer wall 50 forms the external surface of the lower body 40. Outer wall 50 forms an outer wall locked indicator 58 and an outer wall unlocked indicator 59 on its lower end which is proximal to base peripheral ridge 48. When the device 10 is in its first position or third position, the upper body wall notch 24 is aligned with outer wall unlocked indicator 59. When the device 10 is in its second position, the upper body wall notch 24 is rotated to be aligned with outer wall locked indicator 58. Outer wall locked indicator 58 is in the shape of a locked padlock whereas outer wall unlocked indicator 59 is in the shape of an unlocked padlock though other shapes can be used to indicate the position of the device 10. The outer wall 50 forms an opposing pair of outer wall cut outs 51. At the clockwise side of each outer wall cut out 51, the outer wall 50 forms an outer wall slot 52 which has a narrow slot entrance 62 and a slot ramp 64. Each outer wall slot 52 has an arcuate length which is at least the same as the arcuate length of the upper body wall locking formations 28.

[0033] In outer wall cut outs 51 are arranged an opposing pair of lower body clips 56. The arcuate length of the outer wall cut outs 51 is slightly greater than the arcuate length of the upper body wall locking formations 28 such that the formations 28 can be moved through the cut outs 51 to engage the clips 56 such that lower body clips 56 resiliently attach the lower body 40 to the upper body 20. Lower body clips 56 each have a lower body clip hook 57 which is shaped to engage with an upper body wall locking formation 28. The lower body clip hooks 57 have a triangular cross-section such that they are in the form of a catch which slopes downwards from an upper end of the lower body clip 56 to slidingly engage with an upper body wall locking formation 28. Lower body clips 56 have a second height above base 41 which is less than the first height. The second height is arranged to be greater than the height of the upper body wall locking formations 28 above upper body wall rim 23 such that the lower body 40 extends below the upper body 20 and that base peripheral ridge 48 is sufficiently spaced from upper body wall rim 23 that the indicators 58,59 are visible in the first position of device 10.

[0034] Outer wall slot 52 is shaped to lock the device 10 in the second position by immobilising the upper body 20 in relation to the lower body 40. The outer wall slot 52 has a limited height such that the upper body 20 cannot be substantially moved vertically in relation to the lower body 40 such that the spike 14 cannot be extended. The upper end of slot entrance 62 is arranged to be at substantially the same level as lower body clip hook 57 such that when the upper body 20 is rotated clockwise in relation to the lower body 40, each upper body locking formation 28 enters each outer wall slot 52. The height of each outer wall slot 52 is tapered by slot ramp 64 such that slot ramp 64 provides resistance to any anti-clockwise rotational movement of the upper body 20 in relation to the lower body 40 to unlock the device 10 and to return it to its first position so as to reduce the risk that the device 10 may be accidentally unlocked. The outer wall slot 52 and the upper body locking formation 28 provide the device 10 with a twist lock which enables the device 10 to be moved to and from the first and second positions by a twisting or rotational movement of the upper body 20 in relation to the lower body 40.

[0035] The invention will now be illustrated with reference to the following Example which is not intended to limit the scope of the claimed invention.

EXAMPLE

[0036] The torque force required to open 450 g jars of Maribel Thin Marmalade having a lid with a diameter of 80 mm was measured using a Mark-10 (USA) Cap Torque Tester MTT01-100.

TABLE-US-00001 TABLE Force/Nm PIERCED Yes/No Sample Yes No 1 3.935 2 3.990 3 4.820 4 5.410 5 1.295 6 4.015 7 1.220 8 4.020 9 0.995 10 4.300 11 0.355 12 5.825 13 0.390 14 4.600 15 0.495 16 4.020 17 1.120 AVERAGE 0.839 4.494

[0037] The results show that the average torque force required to open the 450 g jars of marmalade was 4.494 Nm when the jars were not pierced. After the jars had been pierced using the pressure equalising device according to the invention, the average torque force was reduced to 0.839 Nm which is well within the capabilities of a person with reduced mobility.