CA1223907A

CA1223907A - Perambulator

Info

Publication number: CA1223907A
Application number: CA000508870A
Authority: CA
Inventors: Dieter Glaser
Original assignee: Peg Perego Pines SpA
Current assignee: Peg Perego Pines SpA
Priority date: 1985-06-03
Filing date: 1986-05-12
Publication date: 1987-07-07
Also published as: DE3519855C2; DE3519855A1; IT1186502B; IT8653403V0; IT8667400A0

Abstract

Abstract of the Disclosure The invention relates to a perambulator having a frame and at least four wheels mounted at lower portions of said frame, each front wheel being carried by a respective axle support mounted for swiveling about a vertical axis, and further comprising respective locking means for preventing each axle support from swiveling. In accordance with the invention, a positive and play-free reliable locking is achieved by the provision that the locking means comprises a recess and a locking member adapted to be received there-in, and that the locking member or the recess is of a convergent configuration in the engagement direction.

Description

1 Description The present invention relates to a perambulator having a frame and at least four wheels mounted at lower portions of said frame ? each front wheel being carried by an axle support mounted for swiveling about a vertical axis, and further comprising respective locking means for preventing each axle support from swiveling.
In the case of a perambulator having four wheels it has been found advantageous to mount the front wheels for swiveling displacement about a vertical axis. In this man-nor it impossible to negotiate narrow curves with the per-ambulator or to maneuver it in confined spaces. As soon, however as a perambulator provided with swiveling front 15 wheels is pushed at an increased speed, for instance normal walking speed, the front wheels tend to flutter about the vertical swivel axis, particularly when riding over rough or uneven ground, whereby the stability and the straight-ahead riding properties of the perambulator are greatly impaired. Known perambulators are therefore provided with locking means for the purpose of preventing the wheels from swiveling about their respective vertical axis. Such lock-in means should be uncomplicated and readily operable, so that even an unskilled user is enabled to actuate the lock-25 in means. Due to the fact that certain manufacturing toter-antes are scarcely avoidable without unacceptably increase in the manufacturing costs, and due to the requirement that the locking means have a simple and readily operable construction the swiveling of the wheels cannot be come pletely prevented. There is always some play between coop-crating members, so that at higher traveling speeds of the perambulator the front wheels tend to flutter within a certain range and to thus render the stable straight-ahead riding of the perambulator impossible irrespective of the engaged condition of the locking means. It has also been found disadvantageous that both of the front wheels are provided with a separate locking means, so that the align-Jo mint of the front wheel axles with one another is not en-' h 1 surged in the locked state. Even the slightest deformations of the perambulator frame may thus result in a consider-able deterioration of the riding stability. If a known perambulator of this type is pushed at a higher speed over rough or uneven ground with the locking means engaged, the nevertheless unavoidable front wheel flutter may result in one or both of the front wheels being deflected to such a degree as to exert a strong braking effect on the forward travel of the perambulator. Since this occurrence may happen very suddenly, it is possible that the perambulator is thereby tipped forwards, so that an infant sitting therein is thrown out. This danger is even greater in view of the possibility that one of the two separate locking means is inadvertently released on its own during travel of the perambulator.
It is an object of the invention to provide a perambulator of the type defined in the introduction which combines a simple construction with low-cost manufacture and simple 20 and reliable operation while ensuring positive and play-free locking of the front wheels when so desired.
In order to attain this object, the invention provides that the locking means comprises a recess and a looking member adapted to be received therein, and that the lock-25 in member or the recess is of convergent configuration in the engagement direction.
The perambulator according to the invention distinguishes itself by a number of considerable advantages The proviso 30 ion that the locking means comprises a recess and a lock-in member engage able therewith enables the entire locking means to be manufactured at reasonably low cost. Further-more, in view of reliable operation and in particular of a simple actuation by an unskilled user, it is particularly 35 advantageous to provide a locking member adapted to be in-sorted into a recess, as the proper actuation as well as the function of this arrangement are readily understood.
The convergent configuration in the engagement direction , of the locking member or of the recess ensures that the .

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1 locking member is always in contact with the walls of the recess; whereby the occurrence of play is reliably avoided.
In an advantageous embodiment of the perambulator the in-mention provides that the recess is formed on the axle support, and the locking member is in the form of a lever hingedly mounted on the frame. Since the axle support is usually mounted at the lowermost portion of the frame, the recess is preferably formed at the top of the axle support.
The recess is thus located within the field of view of the perambulator's user so as to be readily viewed. The con-struction of the locking member in the form of a lever hingedly mounted on the frame considerably facilitates the actuation of the locking means, it being merely required to pivot the lever in the direction OIL the recess.
A convergent configuration of the recess permits the employ of a non-convergent lever. Since the axle support is us-Sally an injection-molded plastic member, it is possible to Norm the tapering or convergent recess in a particularly simple and cost-saving manner. on another advantageous embodiment, the lever is of circular cross-sectional shape at least as regards the portion thereof engage able with the recess. This embodiment permits the lever to be coon-comically manufactured of a round bar stock. The side ox I the circular profile facing towards the recess is in effect of convergent configuration in the engagement direction and thus capable ox' preventing the occurrence of play.
In a particularly advantageous embodiment of the permeably-atop, the invention provides that the levers of the respect-ivy locking means are interconnected by a connecting bar.
In this manner it is ensured that the axles of the front wheels are in alignment with one another in the locked state to thereby ensure excellent straight-ahead riding properties of the perambulator.
For ensuring positive contact between the locking member and the recess under all operating conditions, there is advantageously provided a biasing means adjacent the hinged Lo ' -.

1 mounting location of the lever for biasing the lever in the direction of engagement with the recess. In this manner the lever is prevented from being released from engagement with the recess by shocks or vibrations of the permeably-atop. According to a further advantageous provision, the biasing means is adapted to bias the lever to a position out of engagement with the recess. In this manner it is avoided that the lever shifts to the locking position on its own so as to prevent, for instance, the perambulator from traveling around curves.
In an advantageous embodiment, the biasing means is designed in the form off biasing element adapted to be displaced parallel to the pivot axis of the lever and biased by a resilient element in the direction of the lever. This con-struction permits the geometry of the biasing element to be optimized with regard to the available space and at the same time ensures optimum functional properties. In a part-ocularly advantageous embodiment, the biasing element may have a cross-sectional configuration in the shape ox a circular arc segment having its center at the pivot center of the lever. This permits the biasing element to act on the lever over the full pivot range thereof, while the biasing element itself may be of particularly compact a dimensions.
According to another advantageous aspect, the side of the biasing element facing towards the lever may be formed with a ramp configuration rising in circumferential direction from both end portions towards a center portion. As a no-suit, the center portion is formed as a crest dividing thepîvotal displacement of the lever into two sections, namely, a section in which the lever is biased into engagement with the recess, and a second section, in which the lever is biased towards its disengaged position. The lever is I thus in fact prevented from dwelling at intermediate posy itchiness and positively retained in one ox its two positions, whereby the safety and reliability of the locking means is considerably improved. The lever is moreover reliably pro-I

1 vented from being inadvertently shifted from one of its positions to the other by mechanical shocks or vibration of the perambulator.
The front wheels of the perambulator may suitably be designed as twin wheels disposed on opposite sides of the respective axle support. The forces transmitted by the wheels to act on the locking means in the locked state are symmetric with respect to the Swinger line of the lock-in means to thereby ensure a particularly safe and reliable operation.
In a particularly advantageous embodiment, the portion of the axle support provided with the recess is formed with a ramp configuration rising towards the recess from both sides thereof and projecting over at Least part of the wheels. This construction results in a particularly simple operability of the locking means of the perambulator. The lever may be pivoted to its engagement', position with the recess irrespective of the position of the front wheels 9 to be subsequently biased towards this position by the biasing element. Subsequent travel of the perambulator in the straight-ahead direction rissoles in the wheels being aligned and the lever riding up on the axle support portion partially projecting over the wheels and on the 25 ramps formed thereon. In this manner Lowe lever arrives at its locking position on its own and without any further manipulation by the user. As the recess is located within the field of view of the user, the attainment of the locked state can be ascertained in the simplest manner by visual inspection.
Within the scope of the invention it is of course similarly possible to provide a swivel mounting for the rear wheels of the perambulator instead of for its front wheels.

Embodiment of the invention shall now be described by way of example with reference to the accompanying drawings t wherein:

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fig. 1 shows a diagrammatical side elevation of a front end portion of a perambulator frame carrying swivel-mounted front wheels depicted at a position I off-set from the direction of straight-ahead travel fig. 2 shows a perspective view of the front wheel assembly of fig. 1, with a locking means shown in its locked state, and fig. 3 shows a perspective view corresponding to fig. 2 with the locking means in its disengaged state.

Shown in fig. 1 is the lower front end portion of a peramb-ultra frame 4 carrying an axle support 3 mounted for rotation Abbott vertical axis. The lower end portion of axle support 3 carries a front wheel assembly 9 designed lo in the form of a twin wheel arrangement. In the view shown in fig. 1, the straight-aheadriding direction of the per-ambulator is indicated by the arrow A pointing to the left.
Axle support 3 and front wheel assembly 9 mounted therein are shown at a swiveled position 90 offset from the direction of arrow A. Axle support 3 is of substantially symmetric construction and has its center portion formed with an upwards opening slot-shaped recess 1, the bottom wall of which is inclined at an angle with respect to the vertical swivel axis. The top surface of axle support 3 is 25 formed with ramps 10 rising towards recess 1 from opposite sides thereof. The lateral sides of axle support 3 facing towards wheels 9 are provided with extended portions 11 projecting over at least part of each wheel g. A lever 2 is hingedly mounted on frame portion 4 at a spaced position from the vertical swivel axis. The free length of lever 2 is selected so as to permit the lever to be received in recess 1 when axle support 3 is swiveled to the straight-ahead direction A. Also mounted on frame portion 4 is a biasing element 6 to be described in detail with reference 35 to figs. 2 and 3. Biasing element 6 is mounted for disk placement in the direction of the pivot axis of lever 2 and has a cross-sectional configuration of a circular arc -segment. The side surface of biasing element 6 facing to-wards lever 2 is formed with a ramp configuration rising 1 from the two end portions 7 towards a center portion 8, so that this center portion forms the portion of biasing element projecting furthest from frame portion 4. Bias-in element 6 is suitably mounted in a cavity of frame portion 4 and biased by a not shown resilient element, for instance a coil spring, in the direction away from frame portion 4 and towards lever 2. In the embodiment shown, recess 1 is of substantially uniform width, while lever 2 is formed of a round bar stock of circular cross-sectional shape, so that the lower part of lever 2 facing towards recess 1 tapers in the engagement direction.
Fig. 2 shows perspective view of frame portion 4 with axle support 3 mounted thereon for swiveling about the vertical axis and carrying front wheel assembly 9. The top surface of axle support 3 provided with recess 1 is substantially in the form of a circular arc, as viewed in the direction towards the axle of' front wheels 9, the center of said circular arc coinciding with the axis of rotation of the front wheels. The two lateral ramps 10 rising towards recess 1 are located on the end portion of the arcuate top surface of axle support 3 Pacing in the direction opposite the direction of travel Fig. 2 shows the locking means in the engaged position, in which lever 25 2 is received in recess 1. The ramp configuration of the side surface of biasing element 6 is effective to bias lever 2 in the direction towards recess 1. The free end portion of lever 2 is bent upwards, as referred to its position shown in fig. 2, and joins a substantially Horace-octal portion forming a connecting bar 5 and connected in similar manner to the lever of the locking means also-elated with the other front wheel. In this manner it is ensured that the levers of both locking means are pivoted in synchronism with one another. In this manner it is also ensured that both axle supports, when in the locked state, are retained in respective positions in which the axes of rotation of the front wheels on both sides of the peramb- ' ultra are aligned with one another.

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1 For arriving at a disengaged position of the locking means from the engaged position thereof shown in fig. 2, it is merely required to pivot one of the levers 2 or connecting bar 5 in the counterclockwise direction as viewed in fugue This pivotal movement has to overcome the resistance of biasing element 6, or the resistance, respectively, of the resilient element biasing the biasing element 6 out-wards in the direction towards lever 2. This causes bias-in element 6 to be displaced in the direction towards frame portion 4. After passing the center portion 8 of biasing element 6, the respective part of lever 2 engages the ramp portion of biasing element 6 dropping away from center portion 8 to be thereby sully pivoted to the disk engaged position and subsequently retained thereat.

Fig. 3 shows, similar to the illustration of fig. 2, the let hand front wheel of the perambulator at a position corresponding to the one shown in fig. 2, i.e. the straight-ahead riding position. The locking means is shown in the disengaged state, in which lever 2 is released from en-gagement with recess 1. Biasing element 6 is effective to retain lever 2 in this position.
In order to arrive at a locked position of the locking means from the disengaged position thereof shown in fugue, I it is merely required to pivot lever 2 in the clockwise direction as viewed in fig. 3. This entails a lateral disk placement of biasing element 6 until lever 2 arrives at the center portion 8 of biasing element 6. On further pivotal movement of lever 2, the ramp configuration of biasing element 6 is effective to promote the downward movement of the lever and to bias it in the direction towards recess 1 of axle support 3. If in this case axle support 3 is swiveled about its vertical axis from the position shown in fig. 3, in which lever 2 is able to be directly received in recess 1, it is merely required to push the perambulator over a short distance in the straight-ahead riding direction. Due to the front wheel assembly 9 being designed in the manner of a trailing caster assembly, this forward travel results in the front wheel assemblies ,..
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l being swiveled to a position in which their axles are aligned with one another and parallel to the rear wheel axles of the perambulator. During this alignment process, lever 2 rides up on the outer periphery of the respective wheel 9 and over the laterally projecting portion 11 onto the respective ramp 10, so as to subsequently drop into recess 1 as alignment of front wheel assembly 9 is attained As the levers 2 of the two locking means are interconnected by connecting bar 5 the actual locking operation of both locking means occurs simultaneously. Biasing element 6 is subsequently effective to retain lever 2 in positive engagement with recess 1 so as to avoid the danger of an inadvertent release of the locking means.
The present invention is not restricted to the embodiment shown by way of example. It is thus possible to locate the biasing element at another position or to design it in a different manner, for instance in the form of a toggle lever acting on the connecting bar. It is also possible to provide the lever and the recess cooperating therewith at another location or at a different spacing from the vertical swivel axis of the axle support.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A perambulator having a frame and at least four wheels mounted at lower portions of said frame, each of the front wheels being carried by an axle support mounted for swiveling about a vertical axis, and further compris-ing respective locking means for preventing each axle support from swiveling, characterized in that said lock-ing means comprises a recess and a locking member adapted to be received therein, and that said locking member or said recess is of convergent configuration in the engage-ment direction.

2. A perambulator according to claim 1, character-ized in that said recess is formed on said axle support and said locking member is in the form of a lever hingedly mounted on said frame.

3. A perambulator according to claim 1, character-ized in that said recess is of convergent configuration.

4. A perambulator according to claim 2, character-ized in that said recess is of convergent configuration.

5. A perambulator according to claim 1 character-ized in that at least the portion of said lever engage-able with said recess is of circular cross-sectional shape.

6. A perambulator according to claim 2 character-ized in that at least the portion of said lever engage-able with said recess is of circular cross-sectional shape.

7. A perambulator according to any of claims 2, 3 or 4, characterized in that the levers of respective locking means are interconnected by a connecting bar.

8. A perambulator according to claim 5, character-ized in that the levers of respective locking means are interconnected by a connecting bar.

9. A perambulator according to claim 6, character-ized in that the levers of respective locking means are interconnected by a connecting bar.

10. A perambulator according to any of claims 2, 3 or 4, characterized in that adjacent the hinged mounting location of said lever there is provided a biasing means for biasing said lever in the direction of engagement with said recess.

11. A perambulator according to any of claims 5 or 6, characterized in that adjacent the hinged mounting loca-tion of said lever there is provided a biasing means for biasing said lever in the direction of engagement with said recess.

12. A perambulator according to claim 8, character-ized in that adjacent the hinged mounting location of said lever there is provided a biasing means for biasing said lever in the direction of engagement with said recess.

13. A perambulator according to claim 9, character-ized in that adjacent the hinged mounting location of said lever there is provided a biasing means for biasing said lever in the direction of engagement with said recess.

14. A perambulator according to any of claims 2, 3 or 4, characterized in that said lever is adapted to be biased by said biasing means towards a position out of engagement with said recess.

15. A perambulator according to claim 12, character-ized in that said lever is adapted to be biased by said biasing means towards a position out of engagement with said recess.

16. A perambulator according to claim 13, character-ized in that said lever is adapted to be biased by said biasing means towards a position out of engagement with said recess.

17. A perambulator according to one of claims 12 or 13, characterized in that said biasing means is designed in the form of a biasing element displaceable in a direct-ion parallel to the pivot axis of said lever and biased by a resilient element in the direction towards said lever.

18. A perambulator according to claim 15, character-ized in that said biasing means is designed in the form of a biasing element displaceable in a direction parallel to the pivot axis of said lever and biased by a resilient element in the direction towards said lever.

19. A perambulator according to claim 16, character-ized in that said biasing means is designed in the form of a biasing element displaceable in a direction parallel to the pivot axis of said lever and biased by a resilient element in the direction towards said lever.

20. A perambulator according to claim 18, character-ized in that the biasing element has a cross-sectional configuration in the form of a circular arc segment having its center at the center of rotation of said lever.

21. A perambulator according to claim 19, character-ized in that the biasing element has a cross-sectional configuration in the form of a circular arc segment having its center at the center of rotation of said lever.

22. A perambulator according to claim 20, character-ized in that the side of said biasing element facing towards said lever is formed with a ramp configuration rising from both end portions towards a center portion.

23. A perambulator according to claim 21, character-ized in that the side of said biasing element facing towards said lever is formed with a ramp configuration rising from both end portions towards a center portion.

24. A perambulator according to any of claims 2, 3 or 4, characterized in that said front wheels are designed as twin wheels disposed on opposite sides of said axle support.

25. A perambulator according to claim 22, character-ized in that said front wheels are designed as twin wheels disposed on opposite sides of said axle support.

26. A perambulator according to claim 23, character-ized in that said front wheels are designed as twin wheels disposed on opposite sides of said axle support.

27. A perambulator according to any of claims 2, 3 or 4, characterized in that said locking means is disposed to the rear of said vertical swivel axis as viewed in the direction of travel.

28. A perambulator according to any of claims 5, 6 or 25, characterized in that said locking means is dis-posed to the rear of said vertical swivel axis as viewed in the direction of travel.

29. A perambulator according to claim 26, character-ized in that said locking means is disposed to the rear of said vertical swivel axis as viewed in the direction of travel.

30. A perambulator according to any of claims 2, 3 or 4, characterized in that the portion of said axle support provided with said recess is formed with a ramp configuration rising towards said recess from opposite sides thereof.

31. A perambulator according to claim 29, character-ized in that the portion of said axle support provided with said recess is formed with a ramp configuration rising towards said recess from opposite sides thereof.

32. A perambulator according to any of claims 2, 3 or 4, characterized in that the portion of said axle support provided with said recess is designed to partially project over said wheels.

33. A perambulator according to any of claims 23, 26 or 31, characterized in that the portion of said axle support provided with said recess is designed to partially project over said wheels.