VEHICLE RECOVERY LADDER

Abstract

A vehicle recovery ladder includes a body and traction members fastened to the body. Advantageously, in one embodiment any damaged traction members may be readily released and replaced to maintain the performance of the ladder. The traction members may be fastened to the body during forming of the body, Advantageously, the traction members are releaseably fastened to the body.

Claims

1. A vehicle recovery ladder including: a body; a plurality of traction members fastened to the body during forming of the body.

2. A vehicle recovery ladder as claimed in claim 1, wherein the traction members include metal material.

3. A vehicle recovery ladder as claimed in claim 1, wherein each traction member includes a rotational release means for rotationally releasing the traction member from the body.

4. A vehicle recovery ladder as claimed in claim 3, wherein the rotational release means include a thread configured for engaging within the body.

5. A vehicle recovery ladder as claimed in claim 3, wherein the rotational release means include a tool recess configured for receiving a release tool.

6. A vehicle recovery ladder as claimed in claim 1, wherein each traction member includes an inhibiter configured for inhibiting unintentional release of the traction member from the body.

7. A vehicle recovery ladder as claimed in claim 6, wherein the inhibitor includes one or more formations selected from the group consisting of a tongue, a groove, and a blip.

8. A vehicle recovery ladder as claimed in claim 1, wherein each traction member includes a skirt from which a tooth extends.

9. A vehicle recovery ladder as claimed in claim 1, wherein each traction member is over-molded.

10. A vehicle recovery ladder as claimed in claim 1, wherein each traction member includes a retainer from which a tooth extends, and wherein the retainer defines one or more apertures through which the body passes to retain the traction member.

11. A vehicle recovery ladder as claimed in claim 1, wherein each of the traction members includes a retainer from which a tooth extends, and wherein the body is located between the tooth and the retainer of each traction member.

12. A vehicle recovery ladder as claimed in claim 1, wherein the traction members form a bond with the body.

13. A vehicle recovery ladder as claimed in claim 12, wherein the bond is a chemical bond formed by crosslinking of body and traction member materials.

14. A vehicle recovery ladder as claimed in claim 13, wherein the chemical bond is breakable to release the traction members from the body.

15. A vehicle recovery ladder as claimed in claim 12, wherein the bond is a mechanical bond including engaged threads on the traction members and the body.

16. A method of forming a vehicle recovery ladder, the method including the steps of: locating traction members in a mold; and molding a body to form a bond with the traction members.

17. A vehicle recovery ladder including: a body; a plurality of tire traction members releasably fastened to the body, the tire traction members including threads configured for engaging within the body.

18. A vehicle recovery ladder as claimed in claim 17, wherein the threads become engaged within the body when injection molding the body in a mold containing the tire traction members.

19. A vehicle recovery ladder as claimed in claim 17, wherein the traction members include metal material.

20. A vehicle recovery ladder as claimed in claim 17, wherein each traction member includes an inhibiter configured for inhibiting unintentional release of the traction member from the body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Preferred features, embodiments and variations of the disclosure may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to practice the subject matter thereof. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary in any way. The Detailed Description will make reference to a number of drawings as follows:

[0047] FIG. 1a is a plan view of a vehicle ladder in accordance with an embodiment of the present disclosure;

[0048] FIG. 1b is a side sectional view of the vehicle ladder of FIG. 1a;

[0049] FIG. 1c is a side view of the vehicle ladder of FIG. 1a;

[0050] FIG. 2 is a close-up sectional view of the circular inset in FIG. 1a showing various types of traction members in accordance with embodiments of the present disclosure;

[0051] FIG. 3a is an upper perspective view of a first traction member shown in FIG. 2;

[0052] FIG. 3b is a lower perspective view of a first traction member shown in FIG. 2;

[0053] FIG. 4a is an upper perspective view of a second traction member shown in FIG. 2;

[0054] FIG. 4b is a lower perspective view of a second traction member shown in FIG. 2;

[0055] FIG. 5a is an upper perspective view of a third traction member shown in FIG. 2;

[0056] FIG. 5b is a lower perspective view of a third traction member shown in FIG. 2;

[0057] FIG. 6 is a side perspective view of a fourth traction member;

[0058] FIG. 7 shows a preformed ladder body to which the fourth traction members of FIG. 6 are fitted;

[0059] FIG. 8 is an upper perspective view of a non-removable fifth traction member; and

[0060] FIG. 9 shows a ladder with overmolded fifth traction members of FIG. 8.

DETAILED DESCRIPTION

[0061] According to embodiments of the present disclosure, there is provided a vehicle recovery ladder 100 as shown in FIGS. 1a, 1b, and 1c. The ladder includes an elongate molded body 102, and molded traction members 104 that are releasably fastened to the body 104. The traction members 104 are bonded to the body 102 with a chemical and mechanical bond formed during molding. Advantageously, any damaged traction members 104 can be readily released and replaced to maintain the performance of the ladder 100.

[0062] The traction members 104 are normally less durable than a vehicle tire so as to sustain damage before the comparatively more expensive tire. The traction members 104 are formed from polymeric material (e.g. elastomer, polyurethane, thermoplastic, nylon). The body 102 is also formed from polymeric material (e.g. elastomer, polyurethane, thermoplastic, nylon). Typically, the body 102 and the traction members 104 are each integrally formed (e.g. injection molded) from the same material.

[0063] FIG. 2 shows four types of traction member 104, namely: novel first, second, and third traction members 104a, 104b, 104c; and a conventional traction member 105 integrally formed with the body 102. In practice, the ladder 100 would usually consist of a single type of traction member 104a, 104b, or 104c.

[0064] The traction members 104a, 104b, 104c can be clearly seen in FIGS. 3a, 3b, 4a, 4b, 5a, 5b, respectively. Each traction member 104 includes a rotational release for rotationally releasing the traction member 104 from the body 102. The rotational release includes a thread 300. The rotational release also includes a hexagonal tool recess 302 for receiving a release tool (e.g. Allan key) (not shown).

[0065] The ladder 100 includes tongue-in-groove locks for locking the traction members 104 to the body 102. In particular, each traction member 104a, 104b, 104c includes an inhibiter 304a, 304b, 304c, respectively, for inhibiting unintentional release of the traction member 104a, 104b, 104c from the body 102. The inhibiter 304a of the first traction member 104a is a topside tongue for sitting in a complementary groove of the body 102. The inhibiter 304b of the second traction member 104b is an underside groove in which a complementary tongue of the body 102 sits. The inhibiter 304c of the third traction member 104c is an underside groove in which a complementary tongue of the body 102 sits.

[0066] Returning to FIG. 2, the traction member 104a is released from the rear or underside of the ladder 100. Alternatively, the traction members 104b, 104c are released from the topside of the ladder 100. Each traction member 104a, 104b, 104c includes a broad skirt 200a, 200b, 200c, respectively, from which a tooth 202a, 202b, 202c upwardly extends. Each tooth is flanked by a pair of support fillets 306 (see. FIGS. 3a, 4a, 5a). As can best be seen in FIG. 2, each traction member 104 is over-molded by the body 102 to give increased breadth.

[0067] A method of forming the vehicle recovery ladder 100 is now described.

[0068] Firstly, the traction members 104a, 104b, 104c are injection-molded in a traction member mold (not shown) and permitted to set before removal.

[0069] Next, the set traction members 104a, 104b, 104c are positioned in a ladder mold (not shown).

[0070] Next, the body 102 is injection molded into the ladder mold, and a chemical bond forms between the traction members 104a, 104b, 104c (whichever type is used) and the body 102. A mechanical bond forms with engaging threads of the body 102 and the threads 300 of the traction members 104a, 104b, 104c, as shown in FIG. 2. As shown in FIG. 2, the body 102 is overmolded over the embedded traction members 104 and forms a complementary thread with the traction members. The traction members 104 may have a lower melting point than the body 102 to facilitate chemical bonding between the traction members 104 and the body 102. The chemical bond is formed by crosslinking of the traction member and body materials.

[0071] In use, the chemical and mechanical bond is broken when releasing the traction members 104 from the body 102. Another traction member 104 can be threaded into the body 102 to replace a released traction member 104.

[0072] FIG. 6 shows an alternative tire traction member 104d, similar to tire traction member 104b. A first inhibiter 304d, in the form of an interference blip on the thread 300, is provided for inhibiting unintentional release of the traction member 104d from the body 102.

[0073] FIG. 7 shows a pre-formed body 700 which can be used in conjunction with the tire traction member 104d. In particular, the body 700 is molded with receptacles 702 defining internal threads 704. A second inhibiter 706, in the form of an interference blip on the thread 704 at the top of the receptacle 702, is provided for inhibiting unintentional release of the traction member 104d from the body 102. Twisting the tire traction member 104d tight in the receptacle 702 causes the first and second inhibitors 304d, 706 to yield and allow passage of first inhibitor 304d past the second inhibitor 706. The second inhibitor 706 is then impeded from passing over the first inhibitor 304d in a reverse direction when untightening the tire traction member 104d.

[0074] FIG. 8 shows an alternative tire traction member 104e without a thread. Instead, the traction member 104e includes a lower retainer 800 from which an upper tooth 802 extends. The retainer 800 defines apertures 804 through which the polymer passes during molding of the body 102 to retain the traction member 104e. The polymer is also located between the traction member 104e and the retainer 800.

[0075] As can best be seen in FIG. 9, the tire traction member 104e is placed in a mold (not shown), and then over-molded with polymer when forming the body 102. The preformed traction members 104e can be made from durable material (molded polymer, aluminum, ceramic, silicon rubber, rubber, etc.), and are nearly indestructible, so that they will not be damaged, and hence they need not be replaceable.

[0076] A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present disclosure. For example, the traction members 104 may be formed from metal material (e.g. metal alloy), ceramic material or rubber material. Also, in various embodiments, the traction members 104 may be formed of a different material to the body 102 to suit the particular application (e.g. hard metal teeth for military operations). The traction members 104 may be permanently bonded to, and not releasable from, the body 102. Furthermore, the recess 302 may be pentagonal, octagonal, square, slotted, cross or star shaped.

[0077] It is to be understood that the present disclosure is not limited to specific features shown or described, which are currently preferred embodiments of the disclosure.

[0078] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearance of the phrases in one embodiment or in an embodiment in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.