GB2503422A

GB2503422A - A cup-and-ball joint

Info

Publication number: GB2503422A
Application number: GB1208237.6A
Authority: GB
Inventors: Alice Taylor; Luke Petre; James Leitch; Sulke Haro
Original assignee: MAKIEWORLD Ltd
Current assignee: MAKIEWORLD Ltd
Priority date: 2012-05-10
Filing date: 2012-05-10
Publication date: 2014-01-01
Anticipated expiration: 2032-05-10
Also published as: GB2503422B; GB201208237D0

Abstract

A cup-and-ball joint is provided. The cup-and-ball joint may be for use with 3D printed objects, and comprises a ball housing 100 including an external housing 103 and a ball formation 102; and a cup portion 101including a cup formation 105 configured to clasp the ball formation 102 to permit rotation of the housing 100 relative to the cup portion 105. The joint is configured for the external housing 103 to clasp the cup formation 105 to apply tension within the joint, without rotation of the ball housing 100 relative to the cup formation 105. This ensures that the joint does not become loose through use from the wearing down of the joint material.

Description

A JOINT FOR 3D PRINTED OBJECTS

Field of Invention

The present invention is in the field of joints. In particular, but not exclusively, the present invention relates to a new rotational joint for 3D printed objects.

Background

Objects or figurines (such as toys) with rotational joints are often constructed with a ball portion and a cup (or socket) portion. The cup often provides sufficient tension to clasp the ball whilst permitting rotation of the ball portion relative to the cup portion.

Most joints are designed with material that inhibits any natural wear and tear action of frictional rotation, such as ABS plastic, polypropylene, and vinyl.

An alternative to solving the problem of maintaining tension in the joint involves "stringing" the cup and ball together using an elastic string loop or a plastic string object, which allows the ball to move more freely in the cup or socket area, without so much of a requirement for frictional tension. Any possible wearing of the cup and ball is also mitigated by the internal pull of the string.

One manufacturing technique for producing custom objects is becoming more popular. This technique is one form of 3D printing (or "additive manufacturing"), and utilises sintering of a powdered material. This technique often utilises powdered plastic as the sintering material. Objects manufactured from powdered plastic provide good general structure for use with jointed parts, but the 3D printing process results in a rough, somewhat powdery surface on the objects. This rough surface can wear smooth and flat over time if it is in constant, moving contact with another surface, resulting in shrinkage of approximately 0.1-0.2mm. Consequently, simple ball-and-socket joints manufactured using the 3D printing process will result in joints that rapidly become loose through use.

It is an object of the present invention to provide a new joint for 3D printed objects which overcomes the disadvantages of the prior art, or at least provides a useful alternative.

Summary of Invention

According to a first aspect of the invention there is provided a joint for 3D printed objects, comprising: a ball housing, comprising an external housing and a ball formation; and a cup portion, comprising a cup formation configured to clasp the ball formation to permit rotation of the housing relative to the cup portion; wherein the joint is configured for the external ball housing to clasp the cup formation to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in loosening of the joint.

According to a further aspect of the invention there is provided a ball housing for use with a cup portion to form a joint for a 3D printed object, the ball housing comprising a ball formation and an external housing, wherein the external housing is configured to clasp a cup formation of the cup portion to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in a loosening of the joint.

According to a further aspect of the invention there is provided a cup portion for use with a ball housing to form a joint for a 3D printed object, the cup portion comprising a cup formation configured to clasp a ball formation of the ball housing to permit rotation of the ball housing relative to the cup portion and the cup formation configured for an external housing of the ball housing to clasp the cup formation to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in a loosening of the joint.

Other aspects of the invention are described within the claims.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1: shows multiple views of a ball housing for a joint in accordance with an embodiment of the invention; Figure 2: shows multiple views of a cup portion for use with the ball housing of Figure ito form a joint in accordance with an embodiment of the invention; Figure 3: shows multiple views of a ball housing for a joint in accordance with a second embodiment of the invention; Figure 4: shows multiple views of a cup portion for use with the ball housing of Figure 3 to form a joint in accordance with a second embodiment of the invention; Figure 5: shows multiple views of a ball housing for a joint in accordance with a third embodiment of the invention; Figure 6: shows multiple views of a cup portion for use with the ball housing of Figure 5 to form a joint in accordance with a third embodiment of the invention; Figure 7: shows multiple views of a ball housing for a joint in accordance with a fourth embodiment of the invention; and Figure 8: shows multiple views of a cup portion for use with the ball housing of Figure 7 to form a joint in accordance with a fourth embodiment of the invention.

Detailed Description of Preferred Embodiments

The present invention provides a new cup-and-ball joint which provides a figure or object with rotational or moving joints, without wear affecting joint movement or for the need for internal stringing.

The new joint is particularly useful for 3D printed objects where the surfaces of the 3D printed joint are rough. It will be appreciated that not all of the object needs be 3D printed for the new joint to be useful In Figures 1 and 2, a ball housing 100 and cup portion 101 for forming a joint in accordance with an embodiment of the invention are shown.

The ball housing 100 comprises a ball formation 102 and an external housing 103.

The ball formation and external housing may be integrally manufactured.

The cup portion 101 comprises an open cavity 104 configured to receive the ball formation 102 of the ball housing 100 and a cup formation 105 configured to clasp the ball formation 102 to form a rotational joint. The cup formation 105 is also configured to be clasped by the external housing 103 of the ball housing 100.

The cup formation 105 and external housing 103 are configured to permit rotation of the ball housing 100 relative to the cup portion 101.

The mouth 106 of the cavity 104 may be configured to define permitted extent of rotational movement of the cup portion 101 relative to the ball housing 100.

For example, the mouth 106 may be shaped to form a channel and the ball

S

housing 100 may rotate from one orientation through to a second orientation within the channel.

The mouth 106 of the cavity 104 may be shaped to be wider in one location to S assist in insertion into the cavity 104 of the ball formation 102, and narrower in the rest of the mouth 106 to help inhibit dislocation of the joint.

The cup formation 105 may include a guidance means 107, such as recesses within the wall of the cup formation. There may be two recesses in opposing wall sides to receive a portion of the ball formation 102. The recesses may be circular to interface with a curved surface of the ball formation 102.

The guidance means 107 is configured to hold the ball formation 102 in position within the cup formation 105.

The external surface of the cup formation 105 comprises a convex surface.

The inner surface of the external housing 103 comprises a concave surface which is configured to cover (at least partially) the curved exterior surface of the cup formation 105.

The concave and convex surfaces are configured to permit rotation of the ball housing 100 relative to the cup portion 101.

When the ball formation 102 is inserted into the cavity 104 of the cup formation 105, the external housing 103 compresses the cup formation 105 and the cup formation 105 compresses the ball formation 102. This results in tension within the joint between the external housing 103, the cup formation 105, and the ball formation 102.

The result of this tension is that wearing down of material of the ball housing or cup portion 101 does not result in a loosening of the joint.

The cup formation 105 may be configured to be larger than the internal space of the external housing 103 (particularly when the ball formation 102 is inserted into the cup formation 105) and the ball formation 102 may be configured to be larger than the cavity 104 of the cup formation 105.

Therefore, when the ball formation 102 is inserted into the cavity 104 inner pressure is generated when the cup formation 105 clasps the ball formation 102 and when the cup formation 105 is inserted in the external housing 103 outer pressure is generated when the external housing 103 clasps the distended cup formation 105. The reinforcement of the inner pressure by the outer pressure generates the tension within the joint.

The cup portion 101 and ball housing 100 may be manufactured using sintered powdered plastic in an Additive Manufacturing sintering machine. The material may be any powdered plastic (for example, P2200 Nylon polyamide).

The result of the sintering manufacturing process is an object created from melted, powdered plastic. Usually the topmost layer is still "dusty" and powdery, and will wear flat over time and contact. The wear will usually result in the object's size shrinking by approximately 0.1-0.2mm.

Figures 3 and 4 show a ball housing 200 and cup portion 201 for forming a joint of a second embodiment of the invention.

Figures 5 and 6 show a ball housing 300 and cup portion 301 for forming a joint of a third embodiment of the invention.

The interior wall of the cup formation 103 shown in Figure 6 includes insertion means 302 configured to assist the insertion of the ball formation 102 into the cavity 104. The insertion means 302 may be indentations in opposing wall sides. The indentations may widen further away from the mouth 106 of the cavity 104.

The ball formation 102 and/or the cup portion 101 may comprise a through channel 303, 304 permitting airflow.

Figures 7 and 8 show a ball housing 400 and cup portion 401 for forming a joint of a fourth embodiment of the invention.

S A potential advantage of some embodiments of the present invention is that because of the tension generated by the external housing, the cup formation, and the ball formation, wearing down of material of the components of the joint resulting in shrinking of the ball formation and/or smoothing of touching surfaces does not result in loosening of the joint.

While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art.

Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant's general inventive concept.

Claims

SClaims 1. A joint for 3D printed objects, comprising: a ball housing, comprising an external housing and a ball formation; and a cup portion, comprising a cup formation configured to clasp the ball formation to permit rotation of the housing relative to the cup portion; wherein the joint is configured for the external housing to clasp the cup formation to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in loosening of the joint.
2. A joint as claimed in claim 1 wherein the ball housing and the cup portion are manufactured using a sintering manufacturing process.
3. A joint as claimed in claim 2 wherein the sintering manufacturing process uses powdered plastic.
4. A joint as claimed in any one of the preceding claims wherein the external housing and ball formation are integrally manufactured.
5. A joint as claimed in any one of the preceding claims wherein the 3D printed object is a toy or figurine.
6. A joint as claimed in any one of the preceding claims wherein the cup formation comprises a cavity to receive the ball formation, and wherein the mouth of the cavity is wider in one location such that insertion of the ball formation is assisted and narrower in the rest of the mouth such that dislocation of the joint is inhibited.
7. A joint as claimed in any one of the preceding claims wherein the cup formation comprises a cavity to receive the ball formation, and wherein the mouth of the cavity defines the extent of permitted rotation of the ball housing relative to the cup portion.
8. A joint as claimed in any one of the preceding claims wherein the interior surface of the cup formation comprises guidance means for holding the ball formation in position.
9. A joint as claimed in claim 8 wherein the guidance means comprises two recesses in opposing walls of the interior surface of the cup formation.
10. A joint as claimed in any one of the preceding claims wherein the interior surface of the cup formation comprises insertion means for assisting insertion of the ball formation into the cup formation.
11. A joint as claimed in any one of the preceding claims wherein the insertion means comprise indentations on opposing walls of the interior surface of the cup formation.
12. A ball housing for use with a cup portion of claim 13 to form a joint for a 3D printed object, the ball housing comprising a ball formation and an external housing, wherein the external housing is configured to clasp a cup formation of the cup portion to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in a loosening of the joint.
13. A cup portion for use with a ball housing as claimed in claim 12 to form a joint for a 3D printed object, the cup portion comprising a cup formation configured to clasp a ball formation of the ball housing to permit rotation of the ball housing relative to the cup portion and the cup formation configured for an external housing of the ball housing to clasp the cup formation to apply tension within the joint, without preventing rotation of the ball housing relative to the cup portion, such that wearing down of material of the ball housing or cup portion does not result in a loosening of the joint.
14. A method of manufacturing the ball housing as claimed in claim 12 or cup portion as claimed in 13 by sintering plastic.
15. A ball housing as herein described with reference to Figures 1, 3, 5, and 7.
16. A cup portion as herein described with reference to Figures 2, 4, 6, and 8.
17. A joint formed by a ball housing as claimed in claim 15 and a cup portion as claimed in 16.