Side-mounted caster system for steering three-wheeled push chairs

Abstract

A three-wheeled all-terrain vehicle or push chair utilizes an innovative front wheel mount, employing a side-mounted caster mechanism, for improving its pushability and steerability. Because of this approach, lifting is not required to steer the chair, and any size or type and width of wheel can be used. As a result, the invention provides a new class of all-terrain product for the disabled adult market and a rugged, truly off-road runner/jogger/hiker stroller for the young child market.

Claims

1. A three-wheeled push chair, comprising: a frame having a forward end, a rear end, and a width; two rear wheels attached to the rear end of the frame on opposing sides of the width of the frame; a handlebar extending from the rear end of the frame; a half-fork comprising the forward end of the frame; a single front wheel; and a caster assembly attaching the half-fork to the single front wheel on only one side of the front wheel, the caster assembly comprising an axle rotatably supporting the front wheel, a pivot pin pivotally joining the axle to the half-fork to permit steering of the front wheel directionally, and an attachment flange extending horizontally from the axle forwardly to a pivot pin receptacle extending from the half-fork, the pivot pin being disposed through an aperture in a forward portion of the attachment flange to pivotally join the attachment flange to the pivot pin receptacle.

2. The three-wheeled push chair as recited in claim 1, wherein the half-fork and the caster assembly are disposed only on a left side of the front wheel.

3. The three-wheeled push chair as recited in claim 1, wherein the half-fork and the caster assembly are disposed only on a right side of the front wheel.

4. The three-wheeled push chair as recited in claim 1, wherein the push chair comprises a stroller.

5. The three-wheeled push chair as recited in claim 1, wherein the push chair is sized to accommodate adult-sized people.

6. The three-wheeled push chair as recited in claim 1, and further comprising an axle plane lying along a length of the axle, wherein the pivot pin is disposed forwardly of the axle plane when the front wheel is in a straight orientation.

7. A three-wheeled push chair, comprising: a frame having a forward end, a rear end, and a width; two rear wheels attached to the rear end of the frame on opposing sides of the width of the frame; a handlebar extending from the rear end of the frame; a half-fork comprising the forward end of the frame; a single front wheel; and a caster assembly attaching the half-fork to the single front wheel on only one side of the front wheel, the caster assembly comprising: an axle rotatably supporting the front wheel; and a pivot pin pivotally joining the axle to the half-fork to permit steering of the front wheel directionally; wherein the caster assembly further comprises an attachment flange extending horizontally from the axle forwardly to a pivot pin receptacle extending from the half-fork, the pivot pin being disposed through an aperture in a forward portion of the attachment flange to pivotally join the attachment flange to the pivot pin receptacle.

8. The three-wheeled push chair as recited in claim 7, and further comprising an axle plane lying along a length of the axle, wherein the pivot pin is disposed forwardly of the axle plane when the front wheel is in a straight orientation.

9. The three-wheeled push chair as recited in claim 7, wherein the half-fork and the caster assembly are disposed only on a left side of the front wheel.

10. The three-wheeled push chair as recited in claim 7, wherein the half-fork and the caster assembly are disposed only on a right side of the front wheel.

11. The three-wheeled push chair as recited in claim 7, wherein the push chair comprises a stroller.

12. The three-wheeled push chair as recited in claim 7, wherein the push chair is sized to accommodate adult-sized people.

13. The three-wheeled push chair as recited in claim 1, wherein the pivot pin is disposed adjacent to and not above the front wheel.

14. The three-wheeled push chair as recited in claim 7, wherein the pivot pin is disposed adjacent to and not above the single front wheel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A is an isometric view of a first embodiment of a three-wheeled vehicle constructed in accordance with the principles of the present invention;

(2) FIG. 1B is a top view of the vehicle shown in FIG. 1A;

(3) FIG. 1C is a side view of the vehicle shown in FIGS. 1A and 1B;

(4) FIG. 2A is an isometric view of a second embodiment of a three-wheeled vehicle constructed in accordance with the principles of the present invention;

(5) FIG. 2B is a top view of the vehicle shown in FIG. 2A;

(6) FIG. 2C is a side view of the vehicle shown in FIGS. 2A and 2B;

(7) FIG. 3A is an isometric view of a third embodiment of a three-wheeled vehicle constructed in accordance with the principles of the present invention;

(8) FIG. 3B is a top view of the vehicle shown in FIG. 3A;

(9) FIG. 3C is a side view of the vehicle shown in FIGS. 3A and 3B;

(10) FIG. 4A is an isometric view of a fourth embodiment of a three-wheeled vehicle constructed in accordance with the principles of the present invention;

(11) FIG. 4B is a top view of the vehicle shown in FIG. 4A;

(12) FIG. 4C is a side view of the vehicle shown in FIGS. 4A and 4B; and

(13) FIG. 5 is an enlarged view of the inventive side castor construction of a representative embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(14) Referring now more particularly to the drawings, there is shown in the various figures a three-wheeled push chair or stroller (hereinafter push chair) 10 having a frame 12, rear wheels 14, and a front wheel 16. Rear wheels 14 are rotatably mounted on convention hubs 18, or may alternatively be mounted on a common axle (not shown), and may also be equipped with a braking/locking device to assist in slowing the push chair 10 more quickly, and/or in permitting the rear wheels to be rotatably locked. The frame 12 includes a handlebar 20 for a user to employ in pushing and steering the push chair 10, and may also include an actuator 22 for actuating the braking/locking device on the wheels 14.

(15) Now with reference particularly to FIG. 5, there is shown an enlarged view of the front wheel 16 and construction of the associated mounting system therefor, comprising a caster assembly 23 having an axle 24, to which the wheel 16 is rotatably mounted. A half-fork 26 includes a horizontally disposed pivot pin receptacle 28 at its forward end, through a hole of which a pivot pin 30 extends. The pivot pin 30 also extends through a hole in an attachment flange 32, which is horizontally disposed and extends from the axle 24. The pivot pin is forward of an axle plane 36, which lies along the axle 24, and this arrangement is a unique feature of the inventive system. This unique arrangement enables the axle 24, and wheel 16, to track the direction of the pivot pin 30. It is noted that the vertical location of the front half fork 26 is arbitrary, and in the present case was chosen for styling and function.

(16) With reference now to all of the drawing figures, including FIG. 5, in use, with the front wheel 16 pivotally attached to the half fork 26 of the frame 12 by means of the caster assembly 23, as shown in FIG. 5, the front wheel 16 may be steered directionally by pointing the push chair 10 using the handlebars 20 in a desired direction, in response to which the wheel 16 follows by pivoting about the pivot pin 30. Steering or pivoting of the front wheel 16 may be achieved in either direction along arrow 34, up to mechanical limits imposed by contact of the wheel and associated assemblies with the frame 12, and specifically the half-fork 26. The angle through which the wheel 16 may be steered along arrow 34 is arbitrary. In the embodiment illustrated in FIG. 5, which is an enlarged version of the FIG. 1 embodiment, the caster assembly 23 is disposed on the left side of the wheel 16, because such an arrangement was found to easily accommodate a bicycle hitch which may optionally replace the front wheel 16 so that the push chair 10 can become a trailer. However, it is within the scope of the invention to dispose the caster assembly 23 on the right side of the wheel 16 instead.

(17) The embodiment of FIGS. 2A-2C is similar to the embodiment of FIGS. 1A-1C, but the caster assembly 23 and half-fork 26 are differently arranged to permit pivoting of the front wheel 16 to the right, rather than to the left, as shown in FIGS. 1A-1C, as shown. This is a matter of design preference. It is still the case that the pivot pin 30 is disposed forwardly of the axle plane 36. In this embodiment, the wheel 16 may be turned to an angle of up to about 22 degrees to the right.

(18) The embodiment of FIGS. 3A-3C is also similar to those of the earlier FIGS. 1A-1C and 2A-2C, except that the arrangement of the caster assembly 23 and half-fork 26, which in this case permits turning of the wheel 16 to about 90 degrees to the left, as shown.

(19) The embodiment of FIGS. 4A-4C is similar to those of the earlier FIGS. 1A-1C, 2A-2C, and 3A-3C, except that in this case, as discussed above, the half-fork 26 and caster assembly 23 are disposed on the right side of the wheel 16.

(20) As can be seen from these various embodiments, the range of steering for the inventive system is limited only by the angle and size of the half-fork design.

(21) It is noted that, for sake of clarity, a seat is not illustrated in the figures, so that the frame 12 may be more clearly identified and viewed. However, in practice, a seat is provided of course, to be supported by the frame 12 between the two rear wheels 14. The seat may be fixed in place, or may be removable in whole or in part for more compact folding of the frame 12 and for easier cleaning.

(22) Accordingly, although exemplary embodiments of the invention have been shown and described, it is to be understood that all the terms used herein are descriptive rather than limiting, and that many changes, modifications, and substitutions may be made by one having ordinary skill in the art without departing from the spirit and scope of the invention.