GB2265891A

GB2265891A - Gripping device for separating threadedly connected components

Info

Publication number: GB2265891A
Application number: GB9306658A
Authority: GB
Inventors: Robert Muirhead
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-04-07
Filing date: 1993-03-30
Publication date: 1993-10-13
Also published as: GB9306658D0

Abstract

A gripping device has first and second gripping means 10, 12 which grip two separate components eg closure and container, which are threadedly connected, the gripping means being operatively connected for relative rotation to allow removal of one component from the other. Preferably each gripping means comprises a body part 1, 2 with a central aperture to receive a component, the component being gripped by the radially inner ends of elongate fingers 5, 6 which are pivotally mounted on the body part by pins (13, Figure 2) and adjustably protrude into the aperture on movement of handle 30, 40 relative to the body part. A protrusion carried on each finger 5, 6 projects into a slot in a cam ring (3, Figure 2) carried by the handle. By moving the handles 30, 40 in the directions of arrows 31, 41, the upper component gripped by fingers 5 may be unscrewed from lower component gripped by fingers 6. A friction washer and spring (71, 72 Figure 2) may be provided to oppose relative movement between flanged collars of the body parts. <IMAGE>

Description

GRIPPING AID The present invention relates to a gripping aid.

More particularly, the present invention relates to a gripping aid for use with two articles connected and disconnected by relative rotational movement and is intended primarily, but not exclusively, for use in initiating the separation of two articles which are connected by a screw thread or similar.

Such articles include a common domestic container which is open at one end and is provided with an external screw thread in its open-end region. The container is closable by means of a lid portion carrying a corresponding internal screw thread. When it is desired to open the container, it is necessary to undo the screw-threaded connection and this is usually performed manually. However, the amount of force which may be applied with the hands in order, firstly, to grip the container and the lid and, secondly, to rotate them relative to one another is limited by both the strength in the hands of the user and by the frictional interface between the skin and the object.

Moreover, due to distortion, corrosion and other factors it is often difficult to initiate such separation.

Accordingly, difficulties are often encountered in opening such containers, especially by elderly or infirm persons.

Devices are known for achieving separation and uncoupling of two screw-threadedly connected articles including well-known tools such as screwdrivers, spanners and pliers. More specialised devices are known such as pliers which are adjustable and adapted to fit around the lid of a screw-lidded container such as a jar, bottle, toothpaste-type tube or the like.

However, no known device enables two articles (or two parts of one article) to be securely held by the same device simultaneously, thus enabling initiation of separation of a, for example, screw-threaded connection between the articles.

It is therefore desired to provide a device for securely holding an article, by solely frictional forces or otherwise. It is also desired to provide a device by means of which greater turning force or leverage can be achieved than that which may be achieved using the hands.

It is further desired to provide a device for simultaneously gripping two articles linked by a screw thread whilst enabling relative rotational movement of the two articles in order to initiate the separation of a screw threaded connection According to the present invention there is provided a gripping aid comprising a first gripping means and a second gripping means, said first and second gripping means being operatively interconnected by means for enabling relative rotation between said first and second gripping means.

Preferably, at least one of said first and second gripping means is adjustable within a predetermined range, advantageously to ç engage operatively with the external periphery of an article.

Either or both gripping means may comprise one or more displaceable members jointly defining an aperture in which, in use, an article is locatable.

The displaceable members may be displaceable within a predetermined range, thereby decreasing or increasing the size of the internal aperture in order to grip or hold securely the article within the gripping means.

Said displaceable members may be of any size and shape and may be made from any suitable material.

Advantageously, the displaceable members may be in the form of cams mounted on a cam ring. The material from which the cams are formed may be chosen in dependence upon the material of the article with which they are intended to engage. For example, said displaceable members may have rubber pads for engagement with a glass article, or a serrated or toothed edge for engagement with a soft, readily deformed metal article. In such an arrangement, it is desirable if at least three displaceable members are provided.

Said means for enabling relative rotation of said first and second gripping means preferably defines the relative separation of said first and second gripping means, and may be such as to enable the relative separation of said first and second gripping means to be adjustable within a predetermined range, in order, in use, to engage more easily with articles of non-uniform external dimensions.

In a particular preferred embodiment, a gripping device in accordance with the present invention comprises first and second body portions in which one of the body portions is at least partially inserted into the other body portion, said first and second body portions carrying, respectively, first and second gripping means, each gripping means comprising a plurality of pivotal members, each pivotal member having a free end region whereby said free end regions jointly define a central aperture, and wherein said first and second body portions are rotatable with respect to one another, means being provided for frictionally impeding such relative rotation Said gripping aid further preferably comprises means for locating the gripping aid in a preferred position relative to the articles to be separated.

Preferably, each of said gripping means is operable by a rotational movement, i.e. turning the first gripping means relative to the first body portion causes the pivotal members to move into engagement with, for example, a jar. Only once the gripping means are in secure engagement with the articles (e.g. a jar and a lid) will any further rotational force on the gripping means cause relative rotational movement of the two body portions and thus, in this example, the lid to be unscrewed from the jar. The gripping aid preferably includes biasing means for impeding the relative rotation of said body portions until said gripping means are engaged, the force required to overcome the retardation being relatively small compared with the force applied to the two articles. The biasing means may be a spring, a friction washer or other suitable means.

The gripping aid may further comprise means engageable with each said gripping means for increasing the rotational force manually applicable to said gripping means, preferably in the form of an elongate member, i.e. a handle, protruding from each said gripping means perpendicular to the axis of rotation of said body portions.

Further, the gripping aid may be mountable on a wall, table or other such stable surface, preferably by suitably adapting the handle of one of said gripping means to provide fixing means such as a screw plate or a cramp.

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a preferred embodiment of the present invention when inverted; Fig. 2 is a schematic sectional view of the preferred embodiment of Fig. 1; Fig. 3 is a perspective drawing of the preferred embodiment of the first gripping means of the present invention; Fig. 4 is a perspective view of the preferred embodiment of the second gripping means; and Fig. 5 is a perspective of an alternative embodiment of the present invention.

The preferred embodiment of the present invention will be described in relation to its intended use for initiating the removal of a metal lid screwthreadedly connected to a glass jar, although it will be obvious to a person skilled in the art that, for example by appropriate scaling or modification, the present invention is not limited to the following application and may be readily adapted to other uses.

A preferred embodiment of the gripping device in accordance with the present invention comprises upper and lower body portions 1,2 having mounted thereon first and second adjustable gripping means 10,20 respectively.

The upper and lower body portions 1,2 are operatively engageable with one another in order to allow relative rotational movement of the gripping means 10,20.

As shown in Fig. 1, the upper and lower body portions 1,2 each formed in the shape of a cylinder having a flanged collar at one end thereof, the free end of the upper body portion being operatively insertable inside the free end of the lower body portion, the lower body portion partially overlapping the upper body portion, whilst enabling the upper and lower portions to rotate relative to one another about a central axis.

The first and second gripping means 10, 20 are substantially similar in construction and operation.

The following description of the gripping means 10 is therefore equally applicable to the gripping means 20 except where stated.

The gripping means 10 comprises three cams, fingers or vanes 5 pivotally mounted in a fixed position on the first body portion 1 by means of pins 13. The cams 5 are engageable with an upper cam-ring 3 by means of a protrusion 14 projecting from each cam 5 and engaging in an aperture 15 formed in the upper cam ring 3.

As shown in Fig.s 3 and 4, the apertures 15 in the cam rings 3,4 are formed as elongate slots.

Rotation of the cam ring 3 forces the protrusions 14 from each cam 5 to move radially inward or outward so that the aperture defined by the free ends 50 of the cams 5 increases or decreases in size. As noted hereinbefore, each cam also pivots about a pin 13 fixedly located on the body portion 1 and the pivotal movement about the pin 13 causes the free end 50 of each cam 5 to move radially inwardly or outwardly.

In an alternate embodiment (not shown), the cams remain pivotably mounted on the first body portion but, instead of engaging with a slot in a cam ring, are each moved by a guide protrusion on the cam ring which urges the cam in or out.

The cams 5,6 in the upper and lower gripping means 10,20 are generally similar. However, as shown in Fig. 3, the upper cams 5 each have on their inwardly protruding edge 50 a serrated profile which, in use, engages with and securely grips the metal top of a jar, or similar material. As shown in Fig. 4, the cams 6 of the gripping means 20 have rubber pads 60 on their inwardly protruding edge. The pads 60 produce a high frictional engagement with the glass of a jar or other such rigid material in order to grip such without damage.

In this embodiment, a nut and bolt arrangement 7 is used to create friction between the overlapping portions of the upper and lower bodies 1,2 with a friction washer 71 biased against the body portion 1 by means of a spring 72, as shown in Fig.s 1 and 2, although any suitable means, such as a tourniquet operated by a hand wheel, may be used. In an alternate embodiment, a spring, preferably a tension spring, is mounted with one end attached to each gripping means to oppose relative rotational movement of the two means.

As also shown in Figes 1 and 2, a top cover 8 is provided which, in use, ensures that the lid of the jar is aligned, and is engaged by the gripping means 10.

In use, the gripping aid is operated by three actions. Firstly, the gripping aid is placed over the jar, such that the top cover 8 rests on the lid of the jar Secondly, the upper and lower gripping means are engaged, either simultaneously or in any order. The gripping means 10 is engaged on the lid, by rotating the cam ring handle 30 in the direction of arrow 31 shown in Fig. 3 until the cams 5 engage with the lid, or until the cam ring handle reaches the limit of its travel. The gripping means 20 is engaged with the container body by rotating the cam ring handle 40 in the direction of arrow 41 shown in Fig. 4 until the cams 6 grip the glass jar or the cam ring handle reaches the limit of its travel.In an alternate design, cam rings 3 and 4 are exchanged and thus the gripping aid is operated by moving the handles 30 and 40 toward one another (rather than away from one another as in the embodiment shown).

Thirdly, force is applied to the cam ring handles 30 and 40 in the direction of arrows 31,41 respectively in order to cause relative rotation of the first and second gripping means 10, 20 with respect to one another, thus starting to unscrew the lid.

The upper and lower gripping means are released by turning the handles 30,40 in the opposite direction to arrows 31 and 41 respectively, whereupon the gripping aid may be taken off the jar or the action repeated as desired.

Relative rotation of the upper and lower body portions is frictionally retarded to ensure that the upper and lower gripping means securely hold the lid and the jar before relative rotation occurs.

The alternative embodiment shown in Fig. 5 is similar in construction to the preferred embodiment described above except that the upper gripping means 10 comprises a cam ring handle 9 in the form of an elongate arm member 90 which may be fixedly mounted on a surface such as a wall or table.

To use the alternative embodiment, the lower gripping means 20 is operated using the handle 40 to grip the glass jar as in the preferred embodiment, however, since relative rotation of the body portions 1,2 is impeded, continued rotation of the handle 40 causes the upper body portion 10 to rotate relative to the upper cam ring handle 9 thus engaging the upper gripping means 10, whereupon relative rotation of the lid and the jar is effected by further pressure on the handle 40.

Thus, a gripping aid having two gripping means and means for relatively rotating said first and second gripping means has been described which, in use, grips two articles linked by a screw thread with greater frictional force and rotational leverage than may be effected manuallyO

Claims

CLAIMS 1. A gripping aid comprising a first gripping means and a second gripping means, said first and second gripping means being operatively interconnected by means for enabling relative rotation between said first and second gripping means.
2. A gripping aid as claimed in claim 1, wherein at said first gripping means comprises a plurality of displaceable members.
3. A gripping aid as claimed in claim 2, wherein said members are displaceable within a predetermined range.
4. A gripping aid as claimed in claim 3, wherein said first gripping means further comprises a body portion defining an internal aperture capable of receiving an article, each of said members being elongate and having a first end pivotably mounted on said body portion and a second end protruding by an adjustable amount into said aperture, said second end of each member being adapted to operatively engage with said article.
5. A gripping aid as claimed in claim 4, wherein said first gripping means further comprises displacer means operatively engaging with said body portion and said members such that a relative rotational movement between said body portion and said displacer means about an axis passing through said aperture operatively causes movement of said members into or out of said aperture.
6 A gripping aid as claimed in any preceding claim, wherein said second gripping means is of substantially identical form to said first gripping means.
7. A gripping aid as claimed in claim 6, wherein said means for enabling relative rotation of said first and second gripping means defines the relative separation of the first and second gripping means.
8. A gripping aid as claimed in claim 7, wherein said means for enabling relative rotation of said first and second gripping means further enables the relative separation of the first and second gripping means to be adjusted within a predetermined range.
9. A gripping aid as claimed in any preceding claim, wherein said means for enabling relative rotation of said first and second gripping means further comprises biasing means for impeding the relative rotation of said first and second gripping means, such that both said first and second gripping means operatively engage with an article or articles prior to relative rotation.
10. A gripping aid as claimed in claim 9, further comprising means for locating the gripping aid in a predetermined position relative to the article or articles to be gripped.
11. A gripping aid comprising first and second body portions in which one of the body portions is at least partially inserted into the other body portion, said first and second body portions carrying, respectively, first and second gripping means, each gripping means comprising a plurality of pivotal members, each pivotal member having a free end region whereby said free end regions jointly define a central aperture, and wherein said first and second body portions are rotatable with respect to one another, means being provided for frictionally impeding such relative rotation.
12. A gripping aid substantially as hereinbefore described with reference to the accompanying drawings.