ZA200506535B

ZA200506535B - Hitch assembly

Info

Publication number: ZA200506535B
Application number: ZA200506535A
Authority: ZA
Inventors: Leslie M Austin
Original assignee: Avol Marketing Cc
Priority date: 2005-08-16
Filing date: 2005-08-16
Publication date: 2006-08-30

Description

2005 /0653

BACKGROUND TO THE INVENTION

THIS invention relates to a hitch assembly. In particular the invention concerns a hitch assembly which is configured for facilitating automatic coupling between two vehicles by employing the hitch assembly.

Various hitch assemblies have been developed over the years for connecting trailers to towing vehicles. One such hitch assembly is the block-and-ball hitch assembly. This type of assembly comprises a block having a slot therein for receiving a hitch ball. Once located inside the slot of the block, the hitch ball is secured in position with a manually operated locking arrangement. The block-and-ball hitch assembly is normally employed with rigid draw bar trailers, the so-called pup trailers. One severe drawback of these hitch assemblies is that it is not possible to effect automatic coupling and that an operator is required to monitor coupling of the ball with the block and to secure the ball in position. This creates a potentially dangerous situation when miscalculation by the operator could lead to the loss of a limb.

Another hitch assembly known in the art is sold under the trade mark Saf-T-

Ball™. This hitch assembly is also used on pup trailers and has the advantage that it includes means for visibly gauging the amount of wear which a hitch assembly has undergone so that necessary maintenance work can be undertaken before severe damage is caused as a result of such worn hitch assembly components.

An important feature which truck operators need to keep in mind when selecting a hitch assembly for use with a pup trailer is that pup trailers tend to nose dive when a towing vehicle is suddenly brought to a standstill. This characteristic of pup trailers makes it critical that hitches which are used on them are adapted for supporting large vertical forces. Unfortunately, most known automatic hitch assemblies are not capable of supporting the large vertical forces imparted by pup trailers under nosedive conditions.

It is an object of the present invention to provide an alternative hitch assembly which facilitates automatic coupling but can also support large vertical forces imparted by pup trailers.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a hitch assembly for connection to a first vehicle, the hitch assembly comprising: - a male hitch member for coupling to a female hitch member carried by a second vehicle; - a locking arrangement for securing the female hitch member to the male hitch member, the locking arrangement having a cocked position in which the female hitch member is allowed to be moved into a position for coupling with the male hitch member, and a locked position in which the male and female hitch members are held in a coupling position; and - a trigger for cooperation with the locking arrangement, the trigger being movable between a first position in which it secures the locking arrangement in its cocked position, and a second position in which it secures the locking arrangement in its locked position.

Preferably the hitch assembly comprises a support structure for supporting the male hitch member, locking arrangement and trigger.

Typically the support structure includes vehicle attachment means for securing the hitch assembly to the first vehicle.

Preferably the vehicle attachment means comprises a backing plate having a number of holes therein such that the backing plate can be bolted to the first vehicle.

Typically also the support structure includes a base member to which the male hitch member can be attached.

Preferably the locking arrangement includes a locking plate for holding the male and female hitch members in the coupled position.

Advantageously the locking plate is pivotally mounted to the backing plate, typically by way of two hinges.

More preferably the male hitch member comprises a hitch ball.

Preferably the support structure includes a lug.

In a first embodiment of the invention the locking arrangement includes two arms which are pivotally connected to the lug. The arms carry a guide pin which is slidably located inside a guide slot defined by a guide member which is secured to the locking plate. The guide slot has a first position and a second position.

Advantageously the trigger is pivotally secured to the locking arrangement, preferably to the guide member.

In the first embodiment of the invention the locking arrangement is in the cocked position when the guide pin is located in the first position in the guide slot, and in its locked position when the guide pin is located in the second position in the guide slot. In this embodiment the trigger is located in its first position when it secures the guide pin in the first position in the guide slot. The trigger is located in its second position when it secures the guide pin in the second position in the guide slot.

According to a second aspect of the invention there is provided a female hitch component comprising: - a cup housing; - a cup for location inside the cup housing, the cup being shaped for receiving a male hitch member; and - a wear indicator for location inside the housing in communication with the cup for providing a visual indication of the amount of wear which the cup has undergone.

In an embodiment of the invention a portion of the wear indicator protrudes from the cup housing. The wear indicator is supported by a platform which in turn rests on the cup such that as the cup is worn away, the platform can be moved down the cup housing such that a smaller portion of the wear indicator protrudes from the cup housing, thereby giving a visual indication of the amount of wear which the cup has undergone.

The invention extends to a hitch configuration comprising a hitch assembly in accordance with the first aspect of the invention which is connected to a female hitch member in accordance with the second aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings wherein:

Figure 1 shows a perspective view of a hitch assembly in accordance with a first aspect of the present invention;

Figure 2 shows a front view of the hitch assembly;

Figure 3 shows a top view of the hitch assembly;

Figure 3A shows an enlarged portion of the top view;

Figure 4 shows a cross sectional view of a female hitch component in accordance with the present invention;

Figure 5 shows a top view of the female hitch component;

Figure 6 shows the hitch assembly with its locking arrangement located in a cocked position;

Figure 7 shows the hitch assembly with its locking arrangement located in its locked position;

Figure 8 shows a perspective view of a second embodiment of a hitch assembly in accordance with the first aspect of the present invention with its locking arrangement located in its cocked position; and

Figure 9 shows a perspective view of the second embodiment of the hitch assembly with its locking arrangement located in its locked position.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Figures 1, 2, 3 and 3A show a hitch assembly in accordance with the present invention, generally indicated with the reference numeral 10. The hitch assembly 10 comprises a male hitch member 12 for coupling to a female hitch member, not shown, a locking arrangement 14 for securing the female hitch member to the male hitch member 12 and a trigger 16 for cooperation with the locking arrangement 14 in order to secure the male hitch member 12 with the female member when they are coupled. The male hitch member 12, locking arrangement 14 and trigger 16 are attached to a support structure 18.

The support structure 18 comprises a base member 20 which supports the male hitch member 12. The support structure 20 also includes a backing plate 22 having a number of holes 24 therein to provide vehicle attachment means. In use the hitch assembly 10 can be secured to a towing vehicle, not shown, with the use of bolts, also not shown, passing through the holes 24. The support structure 18 further also includes a first and a second lug, indicated respectively with the reference numerals 26 and 28.

The male hitch member 12 is provided by a standard hitch ball, commonly used in the towing industry, and which is shaped as shown.

The locking arrangement 14 includes a locking plate 30 which is pivotally secured to the backing plate 22 with the use of two hinges 32 and 34. The locking arrangement 14 further comprises two arms 36 and 38 which are pivotally secured at their one end to the first lug 26 with the use of a bolt 40 and nut 42. Towards their other end the arms 36 and 38 support a guide pin 42, here in the form of a bolt. A portion of the guide pin 42 passes through a guide slot 44 defined by a guide member 46, the guide member 46 being secured on top of the locking plate 30. It is pointed out that the guide pin 42 is slidably located inside the guide slot 44 for reasons that will become apparent from the description which follows below. The guide pin 42 extends past the guide member 46 and the trigger 16 as can be seen in

Figure 3A.

Figures 4 and 5 show a female hitch component 48 in accordance with a second aspect of the invention. The female hitch component 48 comprises a cup housing 50. The female hitch component 48 also includes a cup 52 which is sized for location inside the cup housing 50. The cup 52 is shaped for receiving the male hitch member 12 and is produced from a relatively soft material which can wear away due to forces imparted thereon by the male hitch member 12. Persons skilled in the field of hitching will appreciate that this is standard practice in the trucking industry and that the worn cup 52 can be replaced when so required.

Persons skilled in the art will however appreciate that it is necessary to provide some means for gauging the amount of wear which the cup 52 has undergone. According to the present invention this object is addressed by providing a wear indicator 54 for location inside the cup housing and in communication with the cup 52. The wear indicator 54 comprises a base portion 56 and domed top portion 58 which protrudes from the cup housing 50 as shown. In this embodiment of the invention communication is effected between the cup 52 and the wear indicator 54 by providing a platform 60 which carries the wear indicator 54 while resting on the cup 52.

It is pointed out that the cup 52 and the wear indicator 54 are secured to the cup housing 50 with the use of grub screws 62.

In use irregularities in road surfaces will cause vehicles to vibrate. Such vibration will cause the male hitch member 12 to impart forces on the cup 52. Over prolonged periods of time such wear will make it necessary to relocate the cup 52 to a position lower down in the cup housing 50 for ensuring proper contact with the male hitch member 12. This will consequently cause the wear indicator 54 to be located further down in the cup housing 50 and hence protrude less from the cup housing 50. This will then provide a visual indication of the amount of wear which a cup 50 has undergone.

It is envisaged that, once the wear indicator 54 no longer protrudes from the cup housing 50, it could be replaced by a new wear indicator 54 having a longer base portion 56. However, once the cup 52 has undergone such wear that also the second wear indicator 54 no longer protrudes from the cup housing 50 a truck operator will know that it is necessary to replace the cup 52.

The cup housing 50 is attached to a support configuration 64 which can be secured to a rigid draw bar with the use of bolts, not shown.

The operation of the hitch assembly 10 will now be described with specific reference to Figures 6 and Figure 7 of the drawings. In Figure 6 the hitch assembly 10 is located in a cocked position. In order to locate the hitch assembly 10 in its cocked position the guide pin 42 is caused to move along the guide slot 44 in the guide member 46, the guide slot 44 being shaped as shown. The guide slot 44 has a first and a second position respectively indicated with the reference numerals 70 and 72. By moving the guide pin 42 from the second position 70 to the first position 72 the guide member 46, which is secured to the locking plate 30, will cause the locking plate 30 to pivot. Once the guide pin 42 has been located in its first position, the trigger 16, which is pivotally connected to the guide member 46 and shaped as shown, can be located by a user in a first position to secure the guide pin 42 in its first position.

The female hitch component 48 is now brought closer for coupling with the male hitch member 12. The configuration of the hitch assembly 10 is such that as the female hitch component 48 is brought into a position in which it can couple with the male hitch member 12 the female hitch component 48 will impart an upward force on the locking plate 30 causing it to pivot upwardly thereby dislodging the trigger 16 from its first position. As the female hitch component 48 is coupled to the male hitch member 12 the locking plate 30 will move downwards under the influence of gravity. This in turn causes the guide pin to 42 to move along the guide slot 44 towards its second position 72.

Figure 7 shows the hitch assembly 10 located in its locked position wherein the guide pin 42 has been located in its second position 72 and the locking plate deters the female hitch component 48 from being uncoupled from the male hitch member 12. However, to ensure that the locking plate 30 does not fly open when vehicles move over very irregular road surfaces it is necessary to secure the guide pin 42 in its first position 72. This is achieved by locating the trigger 16 in its second position, also under the influence of gravity, shown in Figure 7. In this position the guide pin 42 can not be moved along the guide slot 44 and hence the locking plate 30 can not fly open.

As a further means of securing the locking arrangement 14 in its locked position is its envisaged that the second lug 28 on the support structure 18 can be provided with a hole therein and that a locking element 74, shown in

Figure 1, can also be provided with a hole therein. A padlock can now be used to lock the locking arrangement 14 in position.

Figures 8 and 9 show a second embodiment of a hitch assembly in accordance with the present invention, generally indicated with the reference numeral 100. The hitch assembly 100 operates in exactly the same manner as the hitch assembly 10. The hitch assembly 100 does however employ hinges 102 and 104 which are different to the hinges 32 and 34 of the hitch assembly 10. The hinges 102 and 104 are shaped as shown and serve to provide an enhanced leverage on locking plate 106 as compared to that of the hinges 32 and 34 on the locking plate 30.

A hitch assembly as described above which can be located in a locked configuration due to the influence of gravity provides an alternative automatic hitching system to those known in the prior art.

Claims

1. A hitch assembly for connection to a first vehicle, the hitch assembly comprising: - a male hitch member for coupling to a female hitch member carried by a second vehicle; - a locking arrangement for securing the female hitch member to the male hitch member, the locking arrangement having a cocked position in which the female hitch member is allowed to be moved into a position for coupling with the male hitch member, and a locked position in which the male and female hitch members are held in a coupled position; and - a trigger for cooperation with the locking arrangement, the trigger being movable between a first position in which it secures the locking arrangement in its cocked position, and a second position in which it secures the locking arrangement in its locked position.

2. A hitch assembly according to claim 1 comprising a support structure for supporting the male hitch member, locking arrangement and trigger.

3. A hitch assembly according to claim 2 wherein the support structure includes vehicle attachment means for securing the hitch assembly to the first vehicle.

4. A hitch assembly according to claim 3 wherein the vehicle © attachment means comprises a backing plate having a number of holes therein such that the backing plate can be bolted to the first vehicle.

5. A hitch assembly according to either claim 3 or claim 4 wherein the support structure includes a base member to which the male hitch member can be attached.

6. A hitch assembly according any one of the preceding claims wherein the locking arrangement includes a locking plate for holding the male and female hitch members in the coupled position.

7. A hitch assembly according to claim 6 wherein the locking plate is pivotally mounted to the backing plate.

8. A hitch assembly according to claim 7 wherein the locking plate is pivotally mounted to the backing plate with the use of two hinges.

9. A hitch assembly according to any one of the preceding claims wherein the male hitch member comprises a hitch ball.

10. A hitch assembly according to any one of claims 2 to 9 wherein the support structure includes a lug.

11. A hitch assembly according to claim 10 wherein the locking arrangement includes two arms which are pivotally connected to the lug.

12. A hitch assembly according to claim 11 wherein the arms carry a guide pin which is slidably locatable inside a guide slot defined by a guide member which is secured to the locking plate, the guide slot having a first position and a second position.

13. A hitch assembly according to claim 12 wherein the trigger is pivotally secured to the locking arrangement.

14. A hitch assembly according to claim 13 wherein the trigger is pivotally secured to the guide member.

15. A hitch assembly according to claim 14 wherein the locking arrangement is in its cocked position when the guide pin is located in the first position in the guide slot, and in its locked position when the guide pin is located in the second position in the guide slot.

16. A hitch assembly according to claim 15 wherein the trigger is located in its first position when it secures the guide pin in the first position in the guide slot, and in its second position when it secures the guide pin in the second position in the guide slot.

17. A female hitch component comprising: - a cup housing; - a cup for location inside the cup housing, the cup being shaped for receiving a male hitch member; and - a wear indicator for location inside the housing in communication with the cup for providing a visual indication of the amount of wear which the cup has undergone.

18. A female hitch component according to claim 17 wherein a portion of the wear indicator protrudes from the cup housing.

19. A female hitch component according to either claim 17 or claim 18 wherein the wear indicator is supported by a platform which in turn rests on the cup such that as the cup is worn away, the platform can be moved down the cup housing such that a smaller portion of the wear indicator protrudes from the cup housing and thereby giving a visual indication of the amount of wear which the cup has undergone.

20. A hitch configuration comprising a hitch assembly in accordance with any one of claims 1 to 16 which is connected to a female hitch component in accordance with any one of claims 17 to 19.

21. A hitch assembly substantially as herein described with reference to any one of the illustrated embodiments.

22. A female hitch component substantially as herein described with reference to the illustrated embodiment.

23. A hitch configuration substantially as herein described with reference to any one of the illustrated embodiments. Dated this 16" day of August 2005 V/ Spoor & Fisher Patent Attorneys for the Applicant