US2931139A

US2931139A - Knee joint structure for walking dolls

Info

Publication number: US2931139A
Application number: US485793A
Authority: US
Inventors: Cohn David
Original assignee: MODEL PLASTICS CORP
Current assignee: MODEL PLASTICS Corp
Priority date: 1955-02-02
Filing date: 1955-02-02
Publication date: 1960-04-05
Anticipated expiration: 1977-04-05

Description

April 5, 1960 D. COHN' 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet 1 IN VEN TOR.

April 5, 1960 D. COHN 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet 2 INVENTOR. D4 v/o Ca/vn/ April 5, 1960 D. COHN 2,931,139

KNEE JOINT STRUCTURE FOR WALKING DOLLS Filed Feb. 2, 1955 3 Sheets-Sheet 3 INVENTOR. 04 W0 Co HIV 4rraevey United States Patent KNEE JOINT STRUCTURE FOR WALKING DOLLS David Cohn, Brooklyn, N.Y., assignor to Model Plastics SCzorlproration, White Plains, N.Y., a corporation of New Application February 2, 1955, Serial No. 485,793 2 Claims. (Cl. 46173) This invention relates to a knee joint structure for walking type dolls.

In so-called walking dolls, the doll legs are interconnected so that if the doll is moved ahead on a supporting surface, alternating the motion from one leg to the other, the legs will be projected forwardly in alternation to simulate walking. In dolls of this type, it is desirable also to so construct the legs that the members thereof, namely the thighs and the legs proper, may be articulated so as to relatively bend the same between walking and sitting postures. However, for the walking operation it is essential that the'leg members (the thighs and the legs proper) be held in a linearly rigid walking posture, in resistance against the relatively bending action and in resistance against relatively twisting or torsional action of the leg members.

The prime object of my present invention centers about the provision of an improved knee joint structure for a walking type doll in which there is made possible the manual articulation of the knee joint to relatively bend the leg members to and from a sitting posture, and in which the leg and thigh members are held effectively in 'rigid walking posture in resistance against the relative bending action and in resistance against the relative twisting action of the leg and thigh members.

In such walking dolls constructed to also permit articulation of the leg members at the knee, it is highly desirable to so construct the knee joint that the joint is closed and the interior mechanism concealed from view in all relative positions of the thigh member and leg member. It is a further prime object of the invention to devise an articulatable knee joint for walking dolls so constructed that in both the sitting andwalking postures (and in all between positions) of the leg members, the knee joint is substantially closed, and in one form of the invention it is completely closed, the interior mechanism of. the

joint being thereby substantially completely or fully concealed and housed.

To the accomplishment of the foregoing objects and such other objects as may hereinafter appear my invention relates to the knee joint structure for walkiugdolls as sought to be defined in the appended claims and as described in the following specification taken together with the accompanying drawings, in which:

Fig. l is a view of a so-called walking type of doll to which the present invention is applied;

Fig. 2 is a vertical elevational view taken in medial cross-section of the leg members of such a walking doll and showing one form of the knee joint structure embodying the principles of the present invention;

Fig. 3 is a front view taken in cross-section in the plane of the line 3-3 of Fig. 2;

Fig. 4 is a view taken in cross-section along the broken lines 4-4 of Fig. 2;

Fig. 5 is a view similar to Fig. 2 but showing a modified form thereof;

Fig. 6 is a view of Fig. 5 taken in cross-section in the plane of the line 6-6 of Fig. 5;

2,931,139 Patented Apr. 5, 1960 Fig. 7 is a view of Fig. 5 taken in cross-section in the plane of the line 7--7 of Fig. 5;

- Fig. 8 is a fragmentaryview of the essential parts shown in Fig. 5 and showing these parts articulated to a sitting posture position; and

Fig. 9 is a view of Fig. 5 taken in cross-section along the broken lines 9-9 of Fig. 5. 7

Referring now more in detail to the drawings and having reference first to the form of the invention shown in Figs. 1 to 4 thereof, the principles of the invention are shown applied to a walking doll figure D provided with the Walking leg members comprising the upper leg members or thighs 10 and the lower leg members (the legs proper) 12, Fig. 1 showing the posture of the doll in the walking operation. The present invention is particularly directed, as aforesaid, to the knee joint structure generally designated as 14 connecting. the leg members and thigh members of the doll. The knee joint itself is formed by the hollow thigh member 10 terminating in a socket 16 and by the hollow leg member'12 terminating in a ball 18 fitting the socket 16, the ball and socket defining the knee joint proper. The

leg members

10 and 12 may be molded in the form thus depicted, using customary plastic materials which are molded into rigid shapes.

The mechanism for permitting'or enablingthe manual articulation of the knee joint 14 to relatively bend the thigh and

leg members

10 and 12 to and from a sitting posture comprises a rigid link 20 preferably formed from sheet metal anchored at one end to the leg member 12 as by being pivotally connected to a pin or rod 22 extending transversely through the ball 18 of the leg member 12, the said link extending upwardly and protruding into the thigh member 10. The lower end of the link member is confined within an angularly shaped groove or slit 24 formed in the leg member, the width of the groove being just sutficient to accommodate the thickness of the rigid link 20. A tensioning element such as the tension spring 26 is anchored at one end 28 to the thigh member 10, as by being attached to a cross-pin or rod 30 afiixed to the thigh member, and is anchored at the other end 32 to the upper end of the link 20.. The link 20 and the tensioning spring 26 define the mechanism for holding the leg members in jointed condition.

In the form of the invention shown in Figs. 1 to 4 the knee joint is also'constructed and designed so that in the sitting and walking postures of the doll the knee joint is wholly closed and the interior parts of the joint mechanism are fully concealed and housed. This is accomplished by the following structure of the mechanism: the link 20 is provided with ,an angular extension 34 formed with a linear slot "36,v the anchoring element 38 for the end 3-2 of the tensioning spring being arranged to be movable in said slot 36, thiscombined with the constricting of the ball groove or slit 24 to an acute angle, as shown particularly in Fig. 2 of the drawings. With this construction a full bending movement (articulation at the knee) is permitted by the conjoint movement of the link 20 in the limited angular slit 24 of the ball and a toggleaction movement of the tensioning spring (the anchoring element 38) in the slot 36' of the link extension 34. The full bending articulation is illustrated in Fig. 2 of the drawings, the walking posture of the leg members being indicated in full lines and the sitting posture in dot-dash lines. In the full line or walking position the link 20 is vertical and the anchoring element 38 is located in the upper end of the groove 36; and in the dot-dash or sitting position the 'link 20 is moved to a slightly inclined position, the anchoring element 32 being moved to the lower end of the slot 36, the parts being held in both positions by a toggle action.

With the recited construction it will be observed par- ,and in 'all between positions.

,ence characters.

ticularly from Fig. 2. of the drawings that the movement of the link 20 is accommodated in the groove or slit 24 of the ball 18 only over an acute angle, and that the ball 18 provides an exposable surface (see particularly the rear surface 40 of the ball) which is continuous and uninterrupted in both the sittingand walking postures of the legs Thereby complete or full concealment and housing ofthe interior mechanism of the ball joint is achieved.

The means for positively holding the leg and thigh members in rigid walking posture in resistance against the articulation of the members at the knee comprises mating elements consisting of a protruding sector 42 formed at the rear of the ball 18 on which normallyseats the rear edge. ofthe thigh socket. To move-the leg members to asitting posture the leg 12 is slightly pulled relatively to the thigh member 10 sufiicient to effect the release of the normal locking action between the protruding sector 42 and the socket edge 44.

The means for normally holding the leg and thigh members in walking posture in resistance against the relatively twisting or torsional action heretofore referred to is preferably rnade independent of the means just described for resisitng the articulation of the members, and such means comprises the

wall surfaces

46, 46 formedin the socket 16 and protrusions or

lugs

48, 48 on the ball 18, said lugs riding on said wall surfaces during the articulation or bending action, the said lugsactingjagainst the said wall surfaces to resist relative twisting action between the leg member 12 and the thigh member 10.

In Figs. to 9 of the drawings I show a modification of the knee joint structure embodying the principles of the present invention; and in thesefigures the parts which are similar to the parts shown in the form of the invention of Figs. 1 to 5 are designated by similar, but primed, refer- In this modification the ball18' of the knee joint is slitted from a medial plane of the leg member 12' at 50 over a larger angle than the acute angle of the slitted portion 24 of Figs. 1 to 5, and over an agle of substantially 90. However, this slitted portion is of a very narrow width just sufiicient to accommodate the motion of thelink 52, such that'the ball 18' provides an exposable surface that is continuous throughout except for the narrow groove defined by the slit 50 (seeparticularly Fig.

9). The link 52 in this form of the invention is anchored to the leg member 12' by its lower pivotal connection to a pin orrod 54, andprotrudes intothe thigh member the tensioning spring 56 anchored by its upper end 58 to a crosspin 60 being connected at its lower end 62 to the upper protruding end 64 of the rigid link. 1

In this structural form the mechanism for holding the leg and thigh members inwalking posture in resistance against the relatively bending action or articulation of the leg memberscomprises, as before, a protruding sector 42' with which is normally engaged the socket edge portion 44'. The means for independentlynormally holding the leg and thigh members in walking'posture'in resistance against relatively twisting action comprises a plate 66 fixedly attached to the thigh member 10', the same being provided with'a slot 68 through which slidably and nonrotatably extends the upper part of the link 52. To enable a yieldable action at the initiation of a bending or straightening motion of the leg members it is preferred to extend the slot 68, a stop element in the form of a screw 70 being employed to limit the transverse movement of the link 52 in one direction in the slot 68. With this construction the leg members are articulatable between the positions shown in Fig. 5 and in Fig. 8 of the drawings.

The knee joint structure of the invention especially designed for walking type dolls, the manner of assembling the same and the mode of operating the same will, in the main, be fully apparent from the above-detailed description thereof. It will be further apparent that changes may be made in the structure and the relation of the parts without departing from the spirit of the invention defined in the following claims.

I claim:

1. A ball and socket knee joint for a walking type doll comprising a thigh member terminating in a socket, a leg member terminating in a ball for fitting the socket, the ball ,and socket defining the knee joint, means for permitting themanual articulation of the knee joint to relatively bend said members to and from a sitting posture, said means comprising a link anchored to the leg member and protruding into the thigh member, a slotted plate fixed to the thigh member through which the link member extends in slidable but non-rotatable relation thereto, and a tensioning element fixedly anchored at one end to the thigh member and movably anchored at the other end to the end of the link, the ball being slitted only at the rear .and only suificient to accommodate the link during the ment permittingthe said manual articulation of the knee joint to relatively bend said members to and from the said sitting posture.

Beebe H--. Feb. 5, 1957