GB2072489A - Child safety seat for vehicles - Google Patents

Abstract

A child safety set for use in vehicles comprises a moulded plastics seat (10) having a bottom (12), a back (14), and protective sides (16), the seat being fitted with a padded cover (20). A retractor belt (76) leads rearwardly from an emergency locking retractor (70) fastened to the underside of the seat (10) and joins a pair of shoulder belts (78) which extend divergently and upwardly at the back of the seat back (14), forwards and through laterally spaced-apart slots in the seat back (14), and then downwards into a polymeric foam abdominal pad (81). Portions of the shoulder belts (78) corresponding to the pelvic region of a child occupying the seat are embedded within and fixed to the abdominal pad (81) and are fastened at their lower ends to the upper portion of a buckle tongue, which portion is also embedded within the abdominal pad (81). The buckle tongue is arranged to be releasably received in a buckle (96) fixed on the underside of the front of the seat bottom (12). The plastics seat (10) is carried on and strengthened by a tubular metal frame (24) which is constructed to support the safety seat on a vehicle seat and to be secured in place by one of the vehicle seat belts or a special restraint belt. <IMAGE>

Description

SPECIFICATION Child safety seat for vehicles The present invention relates to child safety seats of the type used in vehicles to restrain small children from being thrown from a safely seated position in the event of a collision, or some other sudden stop or upset of the vehicle.

The usual seat belt systems which vehicles are equipped with by the manufacturer are unsuited for use by small children. Accordingly, a variety of special child restraint systems for use in vehicles are available and in widespread use. The most common type of child restraint system comprises a seat which rests on a vehicle seat and is suitably fastened in place either by one of the vehicle safety belts or by a speciai belt. Such child safety seats usually consist of a small plastics shelltype seat having a padded cover and fitted with a restraint belt system comprising a pair of shoulder belts, a waist belt, and a crotch belt. Because children vary considerably in size as they grow from infancy, the belts are usually adjustable.Many of these known restraint belt systems are relatively complicated because of the number of belt sections involved and the adjustable features incorporated in them. They are also frequently cumbersome to put on the child which is to be secured in the seat. Examples of such child safety seats are described and shown in U.S.

Patent Specifications Nos. 3,596,968; 3,606,453; and 3,794,379.

It has also been proposed to include an abdominal pad in the restraint belt system of a child safety seat for enhancing the protection of a child occupant by spreading the load over the child's pelvic area. Examples of such systems are described and shown in U.S.

Specifications Nos. 3,912,328; 4,025,111; and 4,040,664. In these systems a pair of shoulder straps are joined to the abdominal pad by a metal anchor member which in turn joins the shoulder straps to a crotch strap which is fastened to a buckle under the front portion of the seat. Compared to a number of other systems, which are somewhat more complex, these latter systems are comparatively convenient to use, once relatively complicated adjustments have been made so that the system fits the child. On the other hand, the flexible crotch strap and the location of the buckle make it somewhat inconvenient to fasten the buckle tongue which is attached to the end of the crotch strap.

With the aim of improving child safety seats of this type, according to the present invention a child safety seat which comprises a seat bottom a seat back, a pair of shoulder restraint belts leading from laterally spacedapart locations on the seat back above the normal level of the shoulders of a child occupant of the seat to a buckle tongue, and a buckle fixed to the front centre portion of the seat bottom for receiving the tongue to hold the belts over the front of an occupant, is characterised in that portions of the belts which are disposed adjacent the abdomen of an occupant when the buckle tongue is received by the buckle and a portion of the buckle tongue are embedded within and thereby fixed to a polymeric foam abdominal pad which is arranged to cushion and spread belt loads over an occupant's abdomen, the pad maintaining the parts of the belts above the pad in a laterally spaced-apart relationship.

Preferably the abdominal pad is generally "T" shaped in that it includes a relatively narrow lower portion for location between the seat occupant's legs and a relatively wider upper portion for location across the occupant's abdomen.

The abdominal pad preferably has a cover of durable sheet material, such as a plastics leatherette, which encases the foam and imparts stiffness to the pad, although the foam itself is comparatively stiff. The composite stiffness of the pad considerably facilitates applying the restraint belts to a child placed in the seat because the person applying them can grasp the upper portion of the pad and guide the buckle tongue into the buckle much more easily than with presently known crotch straps which require the person applying the belts to the child to grasp the upper portion of the buckle tongue itself in order to secure the tongue to the buckle.

Although the pad can be made by joining two pieces of foam material to each other and to the belts by an adhesive and thereafter fitting a cover, a further aspect of the invention involves the formation of the foam in situ within the cover, the tongue and belt portions, which converge downwards and are joined to the upper end of the tongue, having first been installed within the cover.

Preferably the cover comprises a front panel and a rear panel stitched to each other around their edges to define a cavity between the two panels, and the shoulder belts are bound in the stitching at laterally spaced apart locations along the upper edge of the cover.

A previous improvement in child safety seats which has been made by the inventor and which is preferably included in seats in accordance with the present invention is the provision of an emergency locking belt retractor attached to the underside of the seat, the shoulder restraint belts of the seat passing through slots in the seat back and including portions which extend downwards behind the seat back and which are joined to a retractor belt extending from the emergency locking retractor, the retractor acting to hold the shoulder belts yieldably under tension. Preferably the retractor is of the type which nor mally allows the retractor belt to be withdrawn freely against the rewinding force of a spring, but which locks automatically in the event of acceleration of the retractor belt in the withdrawal direction greater than a predetermined value.

The provision of a retractor in the restraint belt system of the child seat has the advantages of facilitating the proper fitting of the belts to children of various sizes without requiring adjustment, since the belts automatically adjust in length, and of being more comfortable to the child by allowing him or her to move about in the seat, particularly to lean forward. Nonetheless, the belt system is highly effective in an emergency because the retractor automatically locks when the belt is rapidly accelerated.

As mentioned, the shoulder belts pass through slots in the seat back and include portions that extend downwardly behind the seat back to the retractor belt. Preferably the seat is fastened to a rigid frame which includes a frame member adjacent the locations at which the straps extend through the seat back so that the belts engage portions of the frame member whereby the frame carries at least part of the belt loads in an emergency situation.

The seat back may have at least two pairs of slots, each pair being at a different height from any other pair, so that the belts can be adjusted to suit the size of the seat occupant by passing them through the most appropriate pair of slots.

While the retractor allows the belts to adjust in length automatically in order to permit the child to move in the seat, the length of belt that can be unwound from the emergency locking retractor should be relatively short so that the child cannot remove the shoulder belts by loosening them sufficiently in order to climb out of the seat. Accordingly, for adjustment of the belt system to fit children of various sizes, an adjustable detachable buckle is fitted in each shoulder belt, preferably adjacent the retractor belt, so that each shoulder belt can be detached from the retractor belt and its effective length can be altered. This feature, in conjunction with multiple pairs of slots in the seat back ensures that the belt system can be fitted properly to children of various sizes, say from 7 months to 4 years of age.

The present invention thus provides improvements in child safety seats of the general type described earlier. Like the known child safety seats, a seat in accordance with the present invention may have a padded contoured seat having a bottom, a back, and sides, and is constructed to rest on a vehicle seat. The sides prevent the child from being thrown sideways by restraining the head and shoulders of the child, and thereby supplement the restraint belt system in protecting the child in an emergency. Preferably, the seat is mounted on a strong frame made of metal tubing, and the restraint belt system includes an emergency locking retractor fixed to the underside of the seat and providing the advantages already mentioned of allowing the child to move freely and yet protecting the child in an emergency.In addition to facilitating the fastening and unfastening of the belt system from the buckle, the abdominal pad, particularly insofar as it includes a portion that extends down between the child's legs, provides good protection for the pelvic region of the child, particularly the crotch. The lower portion of the abdominal pad is more comfortable to the child, and safer as well, compared with a crotch strap which can rub on the inside of the child's thighs and which can be abrasive to the legs and crotch in an emergency or cause injury to the skin and flesh.

The above-described adjustment features are convenient to use and increase the versatility of the seat so that it can be used for children over a wide range of ages. The fixing of the lower ends of the shoulder belts to the abdominal pad ensures a good fit of the shoulder belts to the occupant and maintains the lateral separation between them without requiring the metal anchor and other relatively complicated components of the previously known abdominal pads.

Examples of the child safety seat in accordance with the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a front elevational view of one example of a child safety seat embodying the present invention, parts of the seat being broken away to illustrate other constructional details; Figure 2 is a side elevational view of the seat shown in Fig. 1; Figure 3 is a rear view of the seat shown in Figs. 1 and 2; Figure 4 is a fragmentary cross section through the front portion of the seat bottom of the seat shown in Figs. 1 to 3; Figure 5 is a front elevational view of an abdominal pad which forms part of the seat shown in Figs. 1 to 4, the lower portion of the pad being broken away; Figure 6 is a side elevational view of the abdominal pad shown in Fig. 5, the lower portion being shown in cross section; ; Figure 7 is a rear elevational view of another example of a child safety seat embodying the invention; Figure 8 is a rear elevational view of the same example shown in Fig. 7, but showing its belt system adjusted differently so as to fit a small child; Figure 9 is a rear elevational view of a third example of a child safety seat embodying the invention; Figure 10 is a perspective view of an adjus table, releasable buckle which could be used in the examples illustrated in Figs. 7 to 9; and, Figure ii is an edge view of the buckle shown in Fig. 10, showing some of the components in cross section.

The child seat shown in Figs. 1 to 3 comprises a moulded plastics seat 10 having a bottom 12, a back 14, and a pair of sides 1 6 and 1 8. The upper portion of each of the sides 1 6 and 18 has a forwardly extending projection 16A, for protecting the head of a child occupant, and both sides 1 6 and 1 8 are shaped in profile to lie laterally adjacent the shoulders, arms, and hips, of the child to restrain it laterally and supplement a restraint belt system of the seat which is described in detail later. The seat 10 is fitted with a padded cover 20, the perimeter of which is pocketed to receive peripheral flanges of the seat 10. Removable snap type buttons 22 fasten the lower rear portions of the cover 20 to the seat 1 0.

The seat 10 is affixed to a frame 24 which includes a one piece bottom and back frame member 26 consisting of an upper back portion 28, a pair of generally vertical side portions 30 and 32, each of which curves downwardly from the upper back portion 28, and a pair of generally parallel horizontal bottom portions 34 and 36 which curve forwardly from the lower ends of the respective side portions and along the sides of the seat bottom 12. The back 14 of the seat 10 is fastened to the upper back portion 28 of the frame member 26 by rivets 38. The other member 40 of the frame is assembled from three pieces.First, there is a generally Ushaped front piece 42 having a horizontal transverse portion 44 located generally under the front of the seat and a pair of generally vertical side leg portions 46, the upper ends of which curve rearwardly and extend under a flange 48 along the front edges of the respective side portions 1 6 and 1 8 of the seat 10.

The rearward upper end of each side leg portion abuts the forward end of respective second and third pieces, rear leg members 50 which are generally Z-shaped when viewed from the side and have a turned-in rearward end portion 52. The rear leg pieces 50 are, preterably, welded to the front piece 42, but other modes of connection can also be used.

A front cross bar 54 located under the front of the seat is welded to the front leg portions 46 of the frame piece 42, and a rear cross bar 56 is welded to the rear leg members 50. The frame members 26 and 40 are connected to each other where they cross at each side by rivets 58 and 60. The sides 1 6 and 1 8 of the seat 10 are fastened to the frame member 40 by rivets 62.

The restraint belt system of the child safety seat shown in Figs. 1 to 3 includes an emergency locking retractor 70 which is housed in a casing 72 and is fastened under the seat bottom 1 2 by a nut and bolt 74 (see Fig. 4).

The retractor is, preferably, of the type which locks in response to a predetermined acceleration of the retractor belt 76 that is wound onto it. The belt is continuously kept under tension by a winding spring but is otherwise free to be pulled from the retractor except when it locks. The retractor 70 can also be of the type which responds to an inertia sensitive device which detects a predetermined acceleration of the vehicle in any direction. Emergency locking retractors have the advantage of permitting the person who is restrained by the belt move relatively freely except when the retractor is locked in an emergency.

The relationship between the length of the retractor belt and the lengths of the shoulder belts are such that only a short length of the retractor belt 76 can be unwound from the retractor 70 so that the child sitting in the seat, though he or she can lean forward on the seat, is not apt to get out of the belt by loosening it too far by pulling it off the retractor.

The retractor belt 76 leads from the retractor a short distance rearwardly and upwardly to the rear portion of the seat and is sewn to one end of each of a pair of shoulder belts 78. Each shoulder belt 78 extends upwardly along the back of the seat and then turns forward and passes through one of a pair of transversely spaced-apart slots 80 located at a suitable height along the back 1 4 of the seat for proper fitting of the shoulder belts 78 to the seat occupant. Each belt 78 then extends downwardly, forwardly and slightly inwardly to an abdominal pad 81. As shown in Figs. 5 and 6, and as particularly apparent from the broken-away portions of those figures, the abdominal pad 81 comprises an outer cover 82 made from a front panel 84 and a rear panel 86 sewn together around the perimeter.

The shoulder belts 78 are bound into the stitching at transversely-spaced locations along the upper edge of the cover. Portions of the shoulder belts extend convergently down within the cavity defined between the panels 84 and 86 of the cover 82 and are joined at the lower end of the pad to a buckle tongue 88, the upper portion of which extends up into the lower end of the cavity. The cavity within the cover 82 is filled with a polymeric foam, such as thermally-blown polyurethene.

The pad 81 is made by sewing the cover 82 with the belt portions and buckle portion inserted into it, and charging the cavity with the uncured polymeric material which is then thermally blown in situ. Accordingly, the belt portions and the buckle tongue portion that are located within the cavity are imbedded within and united to the polymeric foam mass 90 contained within the cover 82. The polymeric foam is sufficiently soft and compressible to provide a cushioning and load-spread ing effect against the body of the child to which the belt system is fitted. On the other hand, the composite structure of the pad 81 is such as to render it quite stiff, partly because of the relative non-extensibility of the covering and the sandwich effect of uniting the covering with the foam material within it and partly because of the inherent relative stiffness of the foam.The stiffness of the pad 80 also maintains a desired separation between the lower ends of the shoulder belt 78 at the points where they enter the pad and are stitched to the cover. The abdominal pad is generally T-shaped as viewed from the front and includes a narrow, elongated generally vertical lower portion 92 that fits between the legs of the child sitting in the seat and a comparatively wide top portion 94 which extends across the abdoment of the child.

The lower end of the buckle tongue 88 is releasably received within a buckle 96 which is fastened to a bracker 98 affixed by a nut and bolt 100 to the underside of the front portion of the seat 1 0. A portion of the bracket is also fastened to the base of the retractor 70 by the nut and bolt 74, thereby enhancing the strength of the belt system.

The buckle tongue enters the buckle 96 through a slot 102 in the bottom portion 12 of the seat 10. The releasing button 96a of the buckle 96 is located under the seat in a location where it is very unlikely that a child could reach down and release the buckle.

Nonetheless, it is conveniently accessible to the person who places the child in the seat and does up the belt system. The upper portion of the buckle tongue (the part which is received within the lower portion 92 of the abdominal pad 80) is bent rearwardly so that when the buckle tongue is locked in the buckle 96, the abdominal pad 81 lies obliquely to the seat bottom 1 2 in a position favorable for comfortable and safe fitting of the upper portion 94 to the abdomen of the child.The lower portion 92 of the pad 80 is sufficiently flexible to allow the pad to bend slightly forward when the child leans forward, and there is also some play between the buckle tongue and the buckle mechanism which affords pivoting of the pad forward and backward so that the child is relatively free to move in the seat and yet is somewhat restrained against moving forward and in any event is held in the seat for restraint upon locking of the retractor in an emergency.

It will be observed, especially from Fig. 2, that the shoulder belts 78 pass over the transverse top portion 28 of the frame member 26. Accordingly, when the belts 78 are under relatively high tension in an emergency, the frame carries a large part of the load that would otherwise by imposed upon the back of the plastic seat 10. Accordingly, the seat need not be as strongly constructed as it would have to be in order to carry the entire load in an emergency. The upper back portion of the seat 10 has molded into it a transverse boxlike stiffener portion 104 which strengthens the region of the back 14 of the seat 10 around the slots 80 through which the belt passes.

An important advantage of the child seat and the components thereof described above and shown in Figs. 1-6 is the ease of hooking up the restraint belt. When the child is buckled into the seat, the person who releases him or her can conveniently grasp any part of the abdominal pad 81: usually, it is most convenient to grasp some part of the upper portion 94 rather than reaching down between the child's legs and grasping the lower portion. The person then pushes on the release button 96a of the buckle 96 and lifts up on the abdominal pad, and once the buckle tongue 88 is moved just a slight distance up to release the locking pin from the receiving hole in the buckle tongue, the hand used to release the buckle is available for use, if necessary, in repositioning or otherwise tending to the child.It is then very easy to swing the abdominal pad 81 up over the child's head and lay it over the back of the seat or onto the back of the vehicle seat, thereby completely freeing the child from restraint by the belt system. A young child can then easily be lifted out of the seat, and an older child can get out of the seat himself. When the child is put into an empty seat, the process is reversed. The user need only grasp some part of the abdominal pad and with only one hand, because of the relative stiffness of the abdominal pad, can easily guide the buckle tongue 88 through the slot 102 in the seat and push it down to lock it to the buckle 96. Meanwhile, the shoulder straps will easily follow the pad over the child's head and become properly positioned over his shoulders.The retractor 70 readily permits the desired lengths of shoulder belts to be pulled out to facilitate positioning of the shoulder straps 78 and reception of the buckle 88 in the buckle 96. Once the child is installed and buckled into the seat, the retractor allows the belts to pull out when the child leans forward, but in an emergency the retractor 70 will lock in response to rapid acceleration of the retractor belt 76 and prevent the shoulder belts 78 bnd the pad 81 from being pushed forward, thereby restraining the infant. The abdominal pad spreads the load of the child's body when it is thrown forward in an emergency over his abdomen and cushions the child against injury. The laterally-extending portions of the upper part 94 of the abdominal pad, acting in conjunction with the shoulder belt, keep the child from being thrown upwardly by engaging the tops of his thighs and holding him down.

Figs. 7 through 9 of the drawings shows two variations of a child seat that is similar in most respects to the one shown in Figs. 1 through 6, but which includes provision in the restraint belt system for adjustment of the lengths, and positions of the shoulder belts for better fitting to very small children and relatively large children. The seat and frame of the two embodiments are almost identical to those of the embodiment of Figs. 1 through 6. The only differences are the addition of a tubular crosspiece 200 welded to the side portions 30 and 32 of the frame member 24 a short distance below the upper portion 28 and the provision of another pair of shoulder belt slots 202 adjacent the bar 200 some distance below the slots 80.

Both embodiments, (that of Figs. 7 and 8 and that of Fig. 9) also include a modified belt system, the modification involving the addition of an adjustable and detachable buckle in each shoulder strap. In the form shown in Figs. 7 and 8, there is a separate buckle 204 in each shoulder strap 206. Two short pieces 208 of belt material are stitched to the end of the retractor belt 76 and, as shown in detail in Figs. 10 and 11, the end of each piece is inserted through a connection slot 210 in a buckle frame 212, folded back on itself a short distance and then stitched by stitching 214.The lower back end of each shoulder belt 206 is passed outwardly through a locking slot 216 in the buckle frame, passes around a lock bar 218, passes back down through the locking slot 216 and leads back on the incoming portion of the belt 206 through a retainer ring 220 which keeps the incoming and outgoing sections of the belt against each other. The lock bar 21 8 is urged by a spring 222 affixed to the frame in a direction to clamp the outgoing segment 206a of the end of the belt 206 against the edge of the locking slot 216. When each shoulder strap 206 is pulled on, such as in an emergency, the belt force is transmitted to the locking bar 218 and clamps it more tightly against the buckle frame 21 2 with a force proportional to the tension on the belt. Accordingly, the buckle securely locks the belt 206 to an adjusted length.The length of the belt is adjusted by pushing the lock bar 218 in a direction opposite that of the force of the spring 222 and taking up or paying out the desired amount of shoulder belt 206. Such adjustment need be made only occasionally as a particular child who uses the chair grows.

When the child who uses the seat is very small, the belts 206 are installed, as shown in Fig. 8, through the lower pair of slots 202 in the back of the seat 10, and the belts are shorted accordingly by means of the respective buckles 204. As shown in Fig. 8, each shoulder belt 206 passes over the cross bar 200 of the frame, which carries the major portion of the belt loads. For a larger child, the belts 206 are installed, as shown in Fig.

7, through the upper slots 80 in the seat 10, again, with suitable adjustment of the belt lengths by means of the respective buckles 204.

The embodiment of Fig. 9 is the same in all respects as the embodiment of Figs. 7 and 8 except for the substitution for the belt pieces 208 and separate buckles 204 of single tandem buckle 230 having a frame 232 that is attached directly to the retractor belt 76. The frame 232 of the buckle 230 has a pair of locking slots, spring-loaded locking bars and retainer rings that correspond in all respects to the buckle components shown in Figs. 10 and 11 and described above.

There is, therefore, provided, in accordance with the present invention, an improved child safety seat characterized by various aspects of construction that contribute to safe restraint of the child by means of a belt system which allows the child some freedom of movement and yet responds to emergency situations by automatic locking of a highly effective belt system coupled to an abdominal pad of unique construction. The seat is easy to use and is well suited to the inclusion of adjustable features that allow it to be used for several years of the child's early period of growth, say from about 7 months to about 4 years of age.

The above-described embodiments are intended to be merely exemplary, and numerous variations and modifications of them will be apparent to those skilled in the art without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention, as defined in the

Claims (11)

appended claims. CLAIMS

1. A child safety seat for use in vehicles, the seat having a seat bottom, a seat back, a pair of shoulder restraint belts leading from laterally spaced-apart locations on the seat back above the normal level of the shoulders of a child occupant of the seat to a buckle tongue, and a buckle fixed to the front centre portion of the seat bottom for receiving the tongue to hold the belts over the front of an occupant, characterised in that portions of the belts which are disposed adjacent the abdomen of an occupant when the buckle tongue is received by the buckle and a portion of the buckle tongue are embedded within and thereby fixed to a polymeric foam abdominal pad which is arranged to cushion and spread belt loads over an occupant's abdomen, the pad maintaining the parts of the belts above the pad in a laterally spaced-apart relationship.

2. A child safety seat according to claim 1, in which the foam abdominal pad is encased within a cover of durable sheet material.

3. A child safety seat according to claim 2, in which the foam pad is formed in situ within the cover, the belt and tongue portions which are emedded in the foam being installed within the cover prior to forming the foam.

4. A child safety seat according to claim 2 or claim 3, in which the cover comprises a front panel and a rear panel stitched to each other around their edges to define a cavity between them, and in which the stitching passes through the shoulder belts at laterally spaced-apart locations along the upper edge of the cover.

5. A child safety seat according to any one of the preceding claims, in which the abdominal pad is substantially T-shaped, hav ing a relatively narrow lower portion for location between an occupant's legs, and a relatively wider upper portion for location across the occupant's abdomen.

6. A child safety seat according to any one of the preceding claims, in which the seat bottom and back are carried by a rigid frame having a frame member adjacent the seat back locations from which the shoulder re straint belts extend, the belts engaging por tions of the frame member whereby at least part of the belt loads are carried by the frame.

7. A child safety seat according to any one of the preceding claims in which the shoulder restraint belts pass through slots in the seat back and include portions which extend downwards behind the seat back and which are joined to a retractor belt extending from an emergency locking retractor which is fixed under the seat bottom and which serves to hold the shoulder belts yieldably under tension.

8. A child safety seat according to claim 7, in which the retractor is of the type which normally allows the retractor belt to be with drawn freely against the rewinding force of a spring, but which locks automatically in the event of acceleration of the retractor belt in the withdrawal direction greater than a predet ermined value.

9. A child safety seat according to any one of claims 1 to 6, in which the seat back locations from which the shoulder restraint belts lead are defined by slots in the seat back through which the belts pass, and there are at least two pairs of such slots, each pair being at a different height from any other pair so that the belts can be adjusted to suit the size of a particular occupant by passing the belts through the most appropriate pair of slots.

10. A child safety seat according to claim 7 or claim 8, in which the slots in the seat back define the locations from which the shoulder restraint belts lead to the abdominal pad, and there are at least two pairs of such slots, each pair being at a different height from any other pair se that the belts can be adjusted to suit the size of a particular occu pant by passing the belts through the most appropriate pair of slots, the portion of each belt generally adjacent the retractor belt having an adjustable and detachable buckle so that each belt can be detached from the retractor belt and its effective length can be altered.

11. A child safety seat according to claim 1, substantially as described with reference to Figs. 1 to 6, orFigs. 7,8, 10and 11,brto Figs. 9 to 11 of the accompanying drawings.