A CONSTRUCTIONAL BUILDING SET COMPRISING GEAR BOXES

Abstract: A constructional building set comprising gear boxes which are provided with guide grooves and shaft passages. The guide grooves and the shaft passages are constructed such that transmission elements can be inserted into the guide grooves from the outer side of the gear box in such a manner that the transmission elements are positioned in alignement with the shaft passages in the gear boxes. When the gear box additionally comprises means for releasable geometrical retention of the transmission elements in their position in alignment with the shaft passages after insertion of the transmission elements into the gear box, it is ensured that the shafts can be pulled out of the assembled gear structure without the transmission elements dropping out of the gear structure. This simplifies the mounting operation and makes it easier to use the gear structure as an assembled unit that can be used for different applications.

Description: A constructional building set comprising gear boxes The present invention concerns a constructional building set comprising gear boxes which are provided with guide grooves and shaft passages constructed such that trans¬ mission elements can be inserted into the guide grooves from the outer side of the gear box so that the transmis¬ sion elements are positioned in alignment with the shaft passages. In connection with constructional building sets e.g. for the building of toy vehicles, cranes, machinery and the like the gear boxes with inserted transmission elements perform various transmission tasks which can be achieved using known gear wheels, racks, chain drives and similar transmission elements. Particularly in connection with toy constructional build- ing sets it is important in view of the motor function of the child that these gear boxes with transmission ele¬ ments are as simple to assemble as possible. Thus, the Danish Patent No. 161 868 discloses a steering mechanism comprising a rack assembly including a rack and a gear wheel which can engage the rack. The gear wheel is mounted in a housing through which also the rack extends, there being provided a groove through which the gear wheel is inserted into the housing, said groove being closed at one end in a manner such that the gear wheel, when inserted into the housing, is positioned in align¬ ment with shaft passages which are provided in the hous¬ ing so that a shaft can easily be inserted through the shaft passages in the housing as well as the shaft hole on the gear wheel. When the shaft is pulled out of the housing and the gear wheel again, the gear wheel can thus drop freely out of the housing. The object of the present invention is to provide a toy constructional building set comprising gear boxes which enable and facilitate assembly of the gear housing, the transmission elements and the associated shafts to a higher degree than the prior art. Another object is to provide a toy constructional building set enabling the shafts to be pulled out from a mounted gear unit without the individual transmission elements dropping out of the gear housing, thereby enabling easy and quick transfer of a gear unit comprising gear box and transmission elements e.g. from one toy structure to another. This is achieved, as stated in claim 1, in that the gear box in the toy constructional building set stated in the opening paragraph additionally comprises means for re¬ leasable geometrical retention of the transmission ele¬ ments in the position in alignment with the shaft pas¬ sages after insertion of the transmission elements into the gear box. This geometrical retention may be established in expedi¬ ent embodiments either by using one or more locking ele¬ ments adapted to be releasably secured on the gear box, such that the guide grooves are blocked from the outer side of the gear box, as stated in claim 2, or in that the gear box is provided with snap means positioned at the guide grooves in such a manner that the transmission elements are secured by the snap means in the gear box in alignment with the shaft passages, as stated in claim 4. The locking elements according to claim 2 may be formed by a cover plate in an expedient embodiment, as stated in claim 3, which ensures extremely simple disassembly and assembly of the gear unit. The snap means according to claim 4 may expediently be formed by constrictions in the above-mentioned guide grooves, as stated in claim 5, whereby the snap means form an integral part of the guide grooves. When the gear box is provided with coupling knobs, as stated in claim 6, the gear box may be incorporated as a unit in a constructional building set comprising building blocks having similar coupling means. In the latter connection, it is expedient that the gear box has an outer configuration with dimensions as stated in claim 7, thereby providing many possibilities of building two or more gear units in the constructional building set together. The invention will be described more fully below with reference to the drawing, in which: Fig. 1 is a lateral view of an embodiment according to the invention of a mounted gear unit in the form of a worm gear. Fig. 2 is a cross-sectional view through the gear unit shown in fig. 1 along the lines A-A. Fig. 3 is a lateral view of another embodiment of the in¬ vention in the form of a right angle gear. Fig. 4 is an end view of the unit of fig. 3. Fig. 5 are sectional views of the gear unit of figs. 3 and 4 along the line C-C in fig. 3. Fig. 6 is a sectional view of the gear unit of figs. 3 and 4 along B-B. Fig. 1 thus shows a gear unit 1 comprising a gear box 1 which is provided with a worm 3 and a gear wheel 4 which engages the worm 3. The worm 3 is positioned in an open- ing 5 in the gear box 2, and a shaft 6 extends in a known manner through shaft passages in the gear box 2 and the worm 3. The gear wheel 4 is similarly secured in the gear box 2 by the shaft 7 which extends through shaft passages 8 in the gear box 2 and through the gear wheel 4 in a known manner. The shafts 6 and 7 are here shown as cross- shafts, i.e. they have a cross-shaped cross-section grip¬ ping in a known manner the cross-shaped shaft passages in the worm 3 as well as the gear wheel 4, thereby ensuring that the shafts 6, 7 and the transmission elements 3, 4 cannot rotate mutually. Fig. 2 is a sectional view of the worm gear of fig. 1 along the line A-A. It will be seen how the worm 3 en- gages the gear wheel 4, which is secured in the box 2 by means of the shaft 7. When the gear unit is to be mounted, the worm 3 is in¬ serted through the opening 5 on one or the other side of the gear box 2, which is defined by the faces 10 and 11. As shown in the drawing, the opening 5 is formed with a converging cross-section, the face 10 being inclined with respect to the face 11. Since the diameter of the worm 3 is slightly larger than the smallest gap between the faces 10 and 11, it is necessary to exert a certain pres¬ sure when inserting the worm 3 into the opening 5. It is hereby ensured that the worm 3 is secured in the gear box 2 by snap-locking. If the shaft 6 is pulled out of both the worm 3 and the shaft passages in the gear box 2, the worm 3 will remain in position because of this snap ef¬ fect and will not drop out of the gear box 2. This fa¬ cilitates both mounting of the gear unit 1 as well as possible transfer of the gear unit 1 from one application to another. If the gear unit 1 in a given toy structure serves as a drive unit for a crane, but should desirably be used e.g. in connection with a vehicle or a machine or the like, the shaft 6 can be pulled out of the gear unit without any problems, and the gear unit can be trans- ferred to the new toy application without the worm drop¬ ping out. Fig. 3 shows another embodiment of the invention, in which the gear unit 20 comprises a gear box 21 which is provided with conical gear wheels 22 and 23, said gear unit 20 being configured as a right-angle gear. The coni¬ cal gear wheels 22 and 23 are connected with the shafts 24 and 25 via shaft passages. A locking part 26, which will be described more fully below, is mounted on the gear box 21. The shaft passage for the shaft 24 thus ex¬ tends through the gear box 21, and the shaft passage for the shaft 25 extends through the locking part 26. The conical gear wheels 22 and 23 are secured in an axial di- rection by the stop element 27, said gear wheels 22 and 23 being thereby fixed in the axial direction with re¬ spect to the gear box 21 and the locking part 26. The locking part 26 is mounted on the gear box 21 in such a manner that it can be removed, said gear housing 21 being provided with coupling studs 28 capable of engaging com¬ plementary coupling means (not shown) on the locking ele¬ ment 26. Fig. 4 shows the gear unit 20 of fig. 3 from the end from which the shaft 24 extends out through the gear box 21. Fig. 5 shows a section through the gear unit of fig. 3 along the line C-C, it being shown how the gear box 21 is formed with a groove 29 in the form of a recess which ex- tends from the upper face of the gear box 21 down past the shaft passage 30, through which the shaft 24 extends. As shown in fig. 5, the locking element 26 blocks the groove 29 so that the gear wheel 22, as shown in fig. 3, cannot drop out in the direction in which the groove 29 extends. However, since the locking element 26 can be separated from the gear box 21, the groove 29 can subse¬ quently be opened. Fig. 6 shows another section along the lines B-B in fig. 4 through the gear unit of figs. 3 and 4, with the shaft passages 31 and 32 extending in the gear box 21 and the locking element 26, respectively. It is additionally shown how the gear box 21 may be provided with an addi¬ tional shaft passage 33, thereby enabling gear units hav¬ ing different functions to be built. The figure moreover shows that the gear wheel 22 is provided with an annular collar 34 which extends into the groove 29 on the gear box 21. It is ensured in this manner that the gear wheel 22 cannot drop out of the gear box 21, since the locking element 26 blocks upwardly, and since the engagement be¬ tween the collars 34 on the gear wheel 22 and the groove 29 ensures that the gear wheel 22 cannot drop laterally out of the gear box 21. It will hereby be possible to pull out the shaft 24 without the gear wheel dropping out. It is clear that it is possible to work the invention in connection with gear units of different structures which provide the same advantage, viz. that it is possible to pull out the shafts from the gear unit without the trans¬ mission elements in the form of e.g. gear wheels, chain wheels, friction wheels or the like dropping out. This permits the shafts, which are used in the gear unit, to have different lengths or structures so that the gear unit can easily be transferred from one application to another. The gear units of the invention therefore provide great advantages in connection with toys, since it is made con¬ siderably easier to mount the gear units and to transfer the gear units to various applications when playing. The motor function required of the playing child therefore does not necessarily have to be just as fine as is the case in connection with known structures.

Claims: P a t e n t C l a i m s : 1. A constructional building set comprising gear boxes which are provided with guide grooves and shaft passages constructed such that transmission elements can be in¬ serted into the guide grooves from the outer side of the gear box so that the transmission elements are positioned in alignment with the shaft passages, c h a r a c t e r ¬ i z e d in that the gear box additionally comprises means for releasable geometrical retention of the trans¬ mission elements in the position in alignment with the shaft passages after insertion of the transmission ele¬ ments into the gear box. 2. A constructional building set according to claim 1, c h a r a c t e r i z e d in that the means for releas¬ able retention of the transmission elements comprise one or more locking elements adapted to be releasably secured on the gear box so that the guide grooves are blocked from the outer side of the gear box. 3. A constructional building set according to claim 2, c h a r a c t e r i z e d in that the gear box is pro¬ vided with coupling knobs at the outlet of the guide grooves on the outer side of the gear box, and that the locking element is formed by a cover plate which has com¬ plementary coupling means and is constructed so as to block the outlet of the guide grooves on the outer side of the gear box after mounting on the coupling knobs. 4. A constructional building set according to claim 1, c h a r a c t e r i z e d in that the means for releas¬ able retention of the transmission elements comprise snap means positioned at the guide grooves in such a manner that the transmission elements are secured by the snap means in the gear box in alignment with the shaft pas¬ sages. 5. A constructional building set according to claim 4, c h a r a c t e r i z e d in that the snap means are formed by one or more constrictions in the cross-section of the guide grooves, said constrictions being provided in front of the shaft passage to which the guide groove leads, seen in relation to the direction in which the transmission element is inserted into the guide groove. 6. A constructional building set according to one of the preceding claims, c h a r a c t e r i z e d in that the gear box, on at least one side, has coupling means posi¬ tioned in a square pattern and adapted to be coupled with other elements in the building set which are provided with complementary coupling means. 7. A constructional building set according to claim 6, c h a r a c t e r i z e d in that the gear box has a substantially box-shaped outer configuration with dimen¬ sions corresponding to a whole multiple of given modular measures in length, depth and width, and that the shaft passages are so located on the sides of the gear box as to enable at least two gear boxes having transmission elements to be built together by means of the coupling means, so that the shaft passages on one gear box are in alignment with shaft passages on the other gear box. 8. A constructional building set according to one of the preceding claims, c h a r a c t e r i z e d in that the shafts are formed with one or more splines which extend in the longitudinal direction of the shaft, and that the shaft hole in the transmission elements have complemen¬ tary splines to engage the longitudinal splines on the shafts. 9. A constructional building set according to one of the preceding claims, c h a r a c t e r i z e d in that the shafts and the shaft holes of the transmission elements have a mutual dimension so as to provide a frictional coupling between the shafts and the transmission elements upon assembly of these.

Inventors: POULSEN OLE VESTERGAARD, SCHMIDT STEN, POULSEN, OLE, VESTERGAARD, SCHMIDT, STEN
Applicants: INTERLEGO AG, LEGO AS, POULSEN OLE VESTERGAARD, SCHMIDT STEN, LEGO A/S, POULSEN, OLE, VESTERGAARD, SCHMIDT, STEN
Application year: 1995
Main classification: A63H33
IPC codes: A63H31, A63H33