EP0334494A1

EP0334494A1 - Swing seats

Info

Publication number: EP0334494A1
Application number: EP89301881A
Authority: EP
Inventors: Günter Beltzig
Original assignee: Sutcliffe Group Ltd
Current assignee: Sutcliffe Group Ltd
Priority date: 1988-03-01
Filing date: 1989-02-24
Publication date: 1989-09-27
Also published as: GB8804781D0; GB2215351A

Abstract

A swing seat (10) comprising a chain (11) embedded in the resilient polymeric material (12). The polymeric material (12) having a shape on or in which a child can sit, and means to attach the chain (11) to a suspension.

Description

This invention relates to swing seats.
One example of a known swing seat is that of belt type described in our laid-open German patent application DE-OS 30 37 387.6.
Care has to be taken to ensure, as far as possible that equipment used in playgrounds shall be safe and cannot cause serious damage or injury to a child as a result of mis-use, vandalism or wear or breakage of the equipment. One of the safety measures adopted in the swing seat just mentioned is a reinforcement in the form of a metal cable but even that is not entirely satisfactory since a determined effort at vandalism by repeated back and forth flexing of the seat can cause strands of the cable to break so producing potentially hazardous wire ends. A further difficulty is that the measures taken to ensure safety of the equipment in use must not add so appreciably to manufacturing costs that the equipment cannot be sold a reasonable price.
US-A-4 478 410 discloses a swing composed of a flexible strap-like seat of rubber or plastics material formed at its underside with integral lengthwise tubes adjacent its front and rear edges. A pair of chains extend through the tubes. Such a seat is open to the objection that the tubes present an easy target for vandalism by means of a pen-knife, although one might expect that the continued presence of the chain would avoid a serious accident. In fact, the chain in such a construction would not provide the safety one would expect it to. That is because the ends of the tubes are uppermost and rain may enter the tubes and accumulate at the lowest point of each where it may, out of sight and over a period of time, cause dangerous corrosion of the metal of chain within the tubes.
It is an object of the invention to provide a swing seat which is economical to manufacture yet safer to use than the known swing seats.
The present invention provides a swing seat comprising a chain located within resilient polymeric material, the polymeric material having a shape on or in which a child can sit, and means to attach the chain to a suspension, characterized in that the chain is embedded in the polymeric material.
Such a swing seat is inherently safe because chain is capable of great strength, is not susceptible to breakage by repeated back and forth flexing and cannot fray into sharp ends. Moreover, the fact that the chain is embedded in the polymeric material, as opposed to being merely sheathed by it, makes it more difficult for vandals to attack and the fact that the chain is embedded prevents water from running into the structure and producing dangerous corrosion of the chain. Another advantage is that chain is relatively cheap and readily available. Thus, a safe, flexible and relatively inexpensive swing seat can readily be made. The chain can support the load of the child even if the polymeric material has been vandalised.
Preferably, the chain comprises a series of simple links. Other types of chain, such as bicycle chain and chains where links are formed in pairs, are available commercially but simple links can provide desired strength at low cost.
Preferably, the chain is made of metal, for example, steel, preferably of at least 2.5 millimetres diameter. Preferably, the metal chain is made up of simple links each of length at least 15 millimetres. Preferably, the chain is made up of links each of length less than 80 millimetres. By these means desired strength and flexibility can be achieved.
Advantageously, the resilient polymeric material is bonded to the chain. In this way, the structure can be made even more resistant to vandalism.
Preferably, the polymeric material is a moulded rubber material. Information on the use of mouldable rubber materials in conjunction with metal reinforcement is to be found in the German specification mentioned above and also in our British patent No. 1 535 728.
A chain embedded in polymeric material can also be used as the suspension chain for a swing seat of the invention. Children often misuse a swing with an ordinary chain suspension by repeatedly throwing the seat up and over the top suspension bar so that the chain becomes wrapped around the bar. The polymeric material in which the chain is embedded prevents such misuse of the swing and enables a child to get a good grip on the suspension without the risk of the child's fingers entering the links.
The seat may be generally in the form of a belt or strap and preferably the chain runs substantially along the longitudinal axis of the belt or strap.
The chain may run within a rib on that side of the seat which is underneath in use.
Advantageously, each long side of the seat includes a dependent skirt of the polymeric material defining an outer wall connected to an inner wall by a multiplicity of buckling struts. Such a structure makes the seat safer because the buckling struts are able to absorb energy in the event of an impact between the seat and a child. Preferably, the multiplicity of buckling struts are defined by blind apertures having their longitudinal axes at right angles to the plane the seat defines when flat. On each long side of the seat the apertures may be arranged in a respective single row.
Advantageously, each inner wall is connected to the rib by further buckling struts arranged substantially at right angles to the rib. Preferably, the further buckling struts are defined by further blind apertures which are large in relation to the first mentioned blind apertures. In this way further buckling struts can be provided without adding substantially to the mass of the seat which would be less safe and more expensive to make if heavier.
Another form of swing seat according to the invention has leg holes and is shaped to receive the lower trunk of a small child. Preferably, the seat has a waist portion within which the chain passes and preferably a crotch portion within which the chain passes.
Advantageously, the chain in the crotch portion is linked at its ends to the chain in the waist portion. Preferably, a respective suspension means is provided at each side of the waist portion and linked to the chain in the waist portion.
Manufacture is simplified if the seat is made from a substantially flat blank of which portions are interconnected to form the seat into its three-dimensional shape.
Swing seats constructed in accordance with the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a section of a part of a suspension chain for a swing seat;
Figure 2 shows a top view of a first swing seat according to the invention;
Figures 2A, 2B and 2C show sections taken respectively along the lines A-A, B-B and C-C marked in Figure 2;
Figure 3 shows a top view of the first swing seat according to the invention.
Figure 4 shows a moulded blank for a second swing seat according to the invention; and
Figure 4A shows a section taken along the line IV-IV marked in Figure 2.

Referring to the drawings, a suspension chain 1 for a child's swing comprises a steel chain 2 embedded in moulded rubber 3 of circular outer section. The steel chain 2 is made up of a series of simple links 4 each of about 6.5 millimetre diameter metal and of length about 25 millimetres and welded closed. Such steel chain is readily available commercially.
The suspension chain 1 is made by surrounding a length of steel chain with uncured rubber in a mould with at least one link of the chain extending beyond each end of the mould, pulling the chain taught, for example, by inserting a respective wedge acting against the mould into the projecting link at each end or by wedging one end and hanging a weight from the other, and subjecting the rubber to heat and pressure to cure the rubber. Preferably, the chain is pre-treated to enhance the adhesion of rubber to the metal. It is most desirable that the steel chain be pulled taut prior to curing of the rubber to ensure that the chain does not sink through the rubber during curing and become visible at the outside of the finished suspension chain.
Figures 2 and 3 show a swing seat 10 of strap or belt type constructed of a length of steel chain 11 embedded in moulded rubber 12 analogously to the embedding of the chain 2 in the rubber 4. The ends of the chain 11 project to permit suspension of the seat 10. The length of the swing seat is approximately 700 millimetres. The chain 11 runs within a rib 13 on the underside of the seat 10 along the longitudinal axis of the seat. Each long side of the seat includes a dependent skirt 14 defining an outer wall 15 connected to an inner wall 16 by a multiplicity of buckling struts 17. The buckling struts 17 are defined by circular section blind apertures 18 having their longitdinal axes at right angles to the plane the seat defines when flat. Each inner wall 16 is connected to the rib 13 by further buckling struts 19 defined by substantially rectangular blind apertures 20 which have an a cross section more than ten times that of an aperture 18.
Figure 4 shows a moulded rubber blank 30 to form a swing seat for a very young child. Chain 31 is embedded in moulded rubber 32 as in the case of the embodiments just described. The rubber blank has leg hole defining portions 33, a crotch portion 34 and waist portions 35. Each end of each waist portion 35 has a respective extension 36 provided with a pair of apertures 37. The blank 30 is formed into a swing seat in the shape of a pair of bathing trunks by overlapping each extension 36 at the bottom of Figure 4 behind the respective extension 36 at the top of Figure 4 so that the waist portions define a continuous loop. The blank is secured in that shape by fastening means, for example, "pop" rivets, fixed through the apertures 37.
The chain 31 embedded within the blank 30 is made up of a crotch section 34 and four waist sections 35. The crotch section 34 is linked to the waist sections 35 by rings 36 and the outer ends of the waist sections terminate in connecting links 38 through which associated ones of the apertures 37 pass. Two of the links 38 are L-shaped and provided with a suspension eye 39 for the finished swing seat made from the blank 30. For comfort a bead 40 of rubber runs around the leg holes of the seat, the bead being outermost in use. If desired, each bead 40 may be reinforced by an embedded length of light chain, for example, of the kind used for attachment to a bath plug.

Claims

1. A swing seat (10) comprising a chain (11) located within resilient polymeric material (12), the polymeric material (12) having a shape on or in which a child can sit, and means to attach the chain (11) to a suspension, characterized in that the chain (11) is embedded in the polymeric material (12).

2. A swing seat as claimed in claim 1, wherein the seat (10) is generally in the form of a belt or strap.

3. A swing seat as claimed in claim 2, wherein the chain (11) runs substantially along the longitudinal axis of the belt or strap.

4. A swing seat as claimed in claim 3, wherein the chain (11) runs within a rib (13) on that side of the seat (10) which is underneath in use.

5. A swing seat as claimed in any one of claims 2 to 4, wherein each long side of the seat includes a dependent skirt (14) of the polymeric material (12) defining an outer wall (15) connected to an inner wall (16) by a multiplicity of buckling struts (17).

6. A swing seat as claimed in claims 4 and 5, wherein each inner wall (16) is connected to the rib (13) by further buckling struts (19) arranged substantially at right angles to the rib (13).

7. A swing seat as claimed in claim 1, wherein the seat has leg holes (33) and is shaped to receive the lower trunk of a small child.

8. A swing seat as claimed in claim 7, wherein the seat has a waist portion (35) within which the chain (31) passes.

9. A swing seat as claimed in claim 7 or claim 8, wherein the seat has a crotch portion (34) within which the chain (31) passes.

10. A swing seat as claimed in claims 8 and 9, wherein the chain (31) in the crotch portion (34) is linked at its ends to the chain in the waist portion (35).

11. A swing seat as claimed in claim 10, wherein a respective suspension means (39) is provided at each side of the waist portion (35) and linked to the chain (31) in the waist portion (35).

12. A swing seat as claimed in any one of claims 7 to 11, wherein the seat is made from a substantially flat blank (30) of which portions (36) are interconnected to form the seat into its three-dimensional shape.