ANTI-ROTATIONAL HITCH BALL
A hitch assembly that includes an anti-rotation mechanism. The hitch assembly generally includes a hitch ball, a ball mount, and a fastener. The invention is directed to a mechanism for preventing rotation of either the hitch ball or the fastener relative to the ball mount. The anti-rotation mechanism of the present invention provides an engagement means for interlocking sections of the hitch ball or fastener with the ball mount, thereby blocking rotation of the hitch ball or fastener relative to the ball mount.
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This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/481,028 filed Jun. 26, 2003 and U.S. Provisional Patent Application Ser. No. 60/521,067 filed Feb. 13, 2004, the entire disclosures of which are hereby incorporated by reference.
BACKGROUND OF INVENTIONA hitch assembly connects a towing vehicle with a towed vehicle, such as a trailer. One common type of hitch assembly includes a hitch ball on the towing vehicle. The hitch ball is often removably mounted on a ball mount secured to the frame of the towing vehicle. The ball mount includes a through hole for receiving a shank portion of the hitch ball. The hitch ball is secured to the ball mount with a fastener that is threaded on the shank portion and tightened down against the ball mount.
During assembly, if the hitch ball is rotated by a wrench, socket driver, or other tool, the fastener tends to rotate along with it. Similarly, if the fastener is rotated by a tool, the hitch ball has a tendency to rotate also. Therefore, to tighten the hitch ball and fastener onto the ball mount, one of the hitch ball or fastener must be blocked from rotating relative to the ball mount while the other is rotated. Typically, this is accomplished by using two wrenches to grasp both the hitch ball and fastener. One wrench is used to hold either the hitch ball or the fastener stationary, while the other wrench is used to tighten down the other.
SUMMARY OF INVENTIONThe present invention relates to a hitch assembly that includes an anti-rotation mechanism. The hitch assembly generally includes a hitch ball, a ball mount, and a fastener. The invention is directed to a mechanism for preventing rotation of either the hitch ball or the fastener relative to the ball mount. The anti-rotation mechanism of the present invention provides an engagement means for interlocking sections of the hitch ball or fastener with the ball mount, thereby blocking rotation of the hitch ball or fastener relative to the ball mount.
BRIEF DESCRIPTION OF DRAWINGSThe hitch assembly of the present invention may be more readily understood by reference to the following drawings. While certain embodiments are shown as illustrative examples of the hitch assembly, the scope of this application should not be construed as limited to these illustrative examples.
The present invention can take the form of a number of embodiments, many of which are described herein. However, one skilled in the art should appreciate that other embodiments incorporating the invention described herein can be formed. The invention is directed to a hitch ball, a ball mount and a fastener and a mechanism for preventing rotation of either the hitch ball or the fastener relative to the ball mount. The anti-rotation mechanism provides an engagement means for interlocking sections of the hitch ball or fastener with the ball mount. The invention is best illustrated in the description of the embodiments below. As representative of the invention,
The hitch assembly 10 includes a hitch ball 12. The hitch ball 12 shown in
The hitch ball 12 is preferably formed as one piece from a metal, such as stainless steel, although other suitable materials, such as plastic, can be used. Additionally, the hitch ball may be formed of multiple interconnecting pieces.
The hitch ball 12 includes a ball portion 14 having a generally spherical configuration centered on a longitudinal axis 16 of the hitch ball. In the illustrated embodiment, the ball portion 14 has a flattened upper end surface 18, but this flattened surface is not required.
A flange portion, 20 of the hitch ball 12 extends from the ball portion 14. The flange 20 includes a flared section 22 and a cylindrical section 24. The flared section 22 of the flange 20 of the hitch ball 12 flares, that is, increases in diameter, from a smaller diameter part 26 adjacent the ball portion 14, to a larger diameter part 28 adjacent the cylindrical section 24.
The cylindrical section 24 of the flange 20 of the hitch ball 12 has a cylindrical outer side surface 30 centered on the axis 16. The cylindrical section 24 also has a planar, annular end surface 32 centered on the axis 16 and extending normal to the axis.
The hitch ball 12 includes a shank 34. The shank 34 extends from the end surface 32 of the flange 20 of the hitch ball 12, in a direction away from the ball portion 14. The shank 34 has a cylindrical configuration centered on the axis 16. The shank 34 has an external thread convolution 36.
It should be apparent to those skilled in the art that the hitch ball 12 could also be shaped or configured differently then described herein. For example, the entire flange 20 could be a cylindrical shape and not include a flared portion. Such modifications are contemplated and are included within this disclosure to the extent they are within the scope of the claims.
The hitch assembly 10 includes a ball mount 40. The ball mount 40 is a portion of the hitch assembly 10 that is fixed to the towing vehicle. In some applications, the vehicle must be fitted for the receipt of a ball mount 40. The ball mount 40 has a bar-like configuration including a body portion 42 that extends generally horizontal when the ball mount is mounted on the vehicle. The body portion 42 has an upper side surface 44 and a lower side surface 45.
A generally circular shank opening 46 is formed in the body portion 42 of the ball mount 40. The shank opening 46 extends completely through the body portion 42 of the ball mount 40. The shank opening 46 of the ball mount 40 is slightly larger in diameter than the shank 34 of the hitch ball 12. As a result, the shank 34 of the hitch ball 12 can be inserted freely through the shank opening 46 in the ball mount 40. When this is done, the hitch ball 12 is rotatable relative to the ball mount 40, about the axis 16.
The hitch assembly 10 also includes a fastener. In the illustrated embodiments, the fastener is a nut 50, but the fastener could also be a threaded cap, a wing nut or other type of fastener. The nut 50 has an internal thread convolution 52 that is engageable with the external thread convolution 36 on the shank 34 of the hitch ball 12.
The hitch assembly 10 also includes a mechanism for blocking rotation of the hitch ball 12 or fastener 50 relative to the ball mount 40. Generally, the mechanism includes a surface located on the hitch ball 12 or fastener 50 that interact with a surface on the ball mount 40 to prevent the rotation of either the hitch ball 12 or fastener 50 that relative to the ball mount 40. With either the hitch ball 12 or fastener 50 blocked from rotating relative to the ball mount 40, only one tool is required to effectively tighten the other component.
In the embodiment shown in
The second pin opening 64 is formed in the upper side surface 44 of the body portion 42 of the ball mount 40. The second pin opening 64 has a cylindrical configuration, although other configurations are possible, extending parallel to the axis 16. In the illustrated embodiment, the second pin opening 64 does not extend completely through the body portion 42 of the ball mount 40, but rather is formed as a bore extending only partially into the ball mount. The second pin opening 64 is located radially outward of the shank opening 46. The second pin opening 64 is spaced apart from the shank opening 46 by the same distance that the first pin opening 62 is spaced apart from the shank opening when the hitch ball is installed through the shank opening.
The pin 60 is preferably formed of a rigid material, such as metal, although other suitable materials, such as plastic, can be used. The pin 60 has a cylindrical configuration with a diameter slightly smaller than the diameters of the first and second pin openings 62 and 64. Alternatively, the pin 60 may have an interference fit in one or both of the first and second pin openings 62 and 64. As shown, the pin 60 is cylindrical but, in general, the pin can be shaped in many configurations so long as it conforms to the shape of the first and second openings 62 and 64. The length of the pin 60 is slightly less than the combined lengths of the first and second pin openings 62 and 64.
The hitch assembly 10 is used by inserting the pin 60 into the first pin opening 62 in the hitch ball 12. The pin 60 could also be integrally formed with the hitch ball 12. In the embodiment shown in
The hitch ball 12 is then positioned on the ball mount 40 so that the shank 34 of the hitch ball extends into the shank opening 46 in the ball mount, and the pin 60 fits into the second pin opening 64 in the ball mount 40. The hitch ball 12 is moved axially into position on the ball mount 40, so that the end surface 32 of the hitch ball 12 is in abutting engagement with the upper side surface 44 of the ball mount.
The fastener 50 is screwed onto the projecting shank 34 of the hitch ball 12. In the embodiment shown in
The hitch assembly 10a (
A first pin opening 62a is formed in the projecting portion 66 of the flange 20a of the hitch ball 12a. The first pin opening 62a is therefore spaced radially outward by a greater distance than the first pin opening 62 of the hitch ball 12 (
In the embodiment shown in
The hitch assembly 10b (
A pin opening 62b is formed in the projecting portion 66b of the flange 20b of the hitch ball 12b. The pin opening 62b is therefore spaced radially outward by a greater distance than the first pin opening 62 of the hitch ball (
In the embodiment shown in
An additional embodiment of the present invention includes a recessed portion that extends from the shank opening 46 of the ball mount 40. The recessed portion is configured to receive a mating piece that is located on either the hitch ball 12 or the fastener 50. The mating piece that is located on the hitch ball 12 or fastener 50 engages with the recessed portion located on the ball mount to prevent rotation of the hitch ball or fastener relative to the ball mount. The recessed portion could vary in size from a small recessed portion on the ball mount to a larger recessed portion that extends around a greater portion of the shank opening 46.
One example of this embodiment is displayed in
The hitch assembly 10d shown in
The hitch assembly 10e (
A corresponding keyway 78 is defined within the shank portion 34e of the hitch ball 12e. In the embodiment shown in
The hitch assembly 10f (
A notch, slot or recess 80 is defined in a portion of the hitch ball flange 20f such that when the shank portion 34f of the hitch ball 12f is inserted through the shank opening 46f of the ball mount 40f, the notch, slot or recess aligns with the pin 60f on the ball mount. The hitch assembly 10f could include one recess 80 or it could include multiple such recesses. The engagement of the notch, slot or recess 80 with the pin 60f prevents the hitch ball 12f from moving relative to the ball mount 40f during the installation or removal of the hitch ball.
The pin 60f can be visible after installation of the hitch ball 12f. The visually perceptible pin 60f allows the user to recognize when the anti-rotation feature is engaged. The location of the pin 60f on the ball mount 40f can be either close to the shank opening 46f or further away. When the pin 60f is located a sufficient distance away from the shank opening 46f, traditional hitch balls can be used because the pin does not interfere with the operation of the traditional hitch balls.
Additionally, the fastener of the present invention can be adapted to include an anti-rotation feature. Illustrative examples of these embodiments are shown in
In addition, when using such a configuration, it is desired that the fastener should be unable to be torqued after installation. If the fastener were torqued, the anti-rotational mechanism could be damaged. For this reason, many of the embodiments including anti-rotational fasteners also include an anti-tamper feature that help prevent the fastener from being turned, or otherwise tampered with after installation. These anti-tamper fasteners could be combined with a hitch ball utilizing a security key socket driver, to serve as a type of hitch lock. Since the fasteners cannot be turned and the hitch ball could only be rotated by a custom formed socket, the hitch assembly could not be unassembled without the custom formed socket.
The hitch assembly 10g (
The hitch assembly 10g includes a nut 82. A pin opening 52 is defined within the surface of the nut 82. The pin opening 52 is adapted to receive the pin 60g of the ball mount 40g. The pin 60g prevents the nut 82 from moving relative to the ball mount 40g during the installation of the hitch ball 12g. This allows the installer to turn the hitch ball 12g with a wrench or other driver while the nut 82 remains stationary. A lock washer pocket 84 is defined in the mounting face of the nut 82 and holds a lock washer 88 in place. Alternative embodiments of this nut 82 may not include this lock washer pocket 84 and lock washer 88. The nut in the embodiment shown in
The nuts utilizing the shuttle pin feature engage with the ball mount 40h as shown in
The blind pin receiving hole 100 totally receives the engagement portion 102 of the shuttle pin 94 but the shuttle pins is not accessible or visible from the upper side of the ball mount 40h. This configuration gives the hitch assembly 10h an improved appearance and also prevents access to the shuttle pin 94 of the nut 90 or 92 while the hitch ball 12h is installed. Since the shuttle pin 94 is inaccessible when the hitch ball 12h is installed the nut 90 or 92 cannot be tampered with while the hitch ball is installed.
With each of the embodiments of the present invention utilizing a pin 60, the pin could be integrally formed in the hitch ball 12, or fastener 50 and engage with the ball mount 40. Also, the pin could be integrally formed in the ball mount 40 and engage with the hitch ball 12 or fastener 50. Alternatively, the pin 60 may be positioned in one of the ball mount 40, hitch ball 12 or fastener 50 and then the components of the hitch assembly 10 could then be fitted together so the pin properly engages the desired components.
The pins 60 that are used by the various embodiments of the present invention could be replaced by a protrusion. The protrusion could be configured and shaped in multiple ways, such as a pyramid or dome shaped protrusion. The protrusion could be located on either the hitch ball 12 or the ball mount 40 and engage with a corresponding recess formed in the other of the hitch ball or ball mount to prevent rotation of the hitch ball in relation to the ball mount. Alternatively, the protrusion could be located on either the ball mount 40 or the fastener 50 and engage with a corresponding recess formed in the other of the ball mount or fastener.
The present invention also includes methods that allow its components to be used with other conventional hitch assembly components that are not similarly adapted for anti-rotation. These methods, such as a pin that can be moved between multiple positions, could also be utilized by the installer to disengage the anti-rotational mechanism of the hitch assembly if it is not needed.
The set screw mechanism in
The threaded pin 120 could be threaded into the upper surface 44k of the ball mount 40k to engage a hitch ball equipped with a pin receiving hole or it could be threaded into the lower surface 45k of the ball mount 40k to engage a nut so equipped. Additionally, when the anti-rotation mechanism is not to be used, the threaded pin 120 can be removed all together or it could be threaded into a side of the ball mount 40k where it would not interfere with the installation of the hitch assembly 10k. Having the pin receiving hole 122 on both the upper surface 44k and the lower surface 45k of the ball mount 40k provides a convenient storage location for the threaded pin 120 when it is not in use.
When the pin 60m is in the raised position, application of a downward force will force the detent 136 out of the lower groove 140 and into the upper groove 138, which corresponds to the dropped position. To move the pin 60m back to the raised position, an upward force is applied to the pin. The upward force moves the detent 136 from the upper groove 138 to the lower groove 140, which corresponds to the raised position.
Although, the set screw, plunger pin and interference fit pin designs illustrate two-position pins, with a raised position and a dropped position, each pin could have multiple positions. For example, a pin mechanism with three positions: a raised position, a dropped position, and a centered position, could be used. Such a pin could be centered within the ball mount 40 with both the top and the bottom of the pin being flush with the upper surface 44 and lower surface 45 of the ball mount.
While the different pin embodiments illustrated in
The hitch assembly 10o also includes a blocking arm 150. The blocking arm 150 is a member that is engageable with the hitch ball 12o and with the ball mount 40o, in a different manner than as described above, to block rotation of the hitch ball relative to the ball mount.
The blocking arm 150 in the illustrated embodiment is a single piece of cylindrical metal rod bent to form a three-dimensional (non-planar) configuration which, as illustrated, includes four legs 152, 154, 156 and 158. Three of the legs 152, 154 and 156 are arranged so that they wrap fairly closely around the ball mount 40o. The fourth leg 158 of the blocking arm 150 is arranged so that when the three legs 152-156 are wrapped around the ball mount 40o, the fourth leg extends laterally into the blocking arm opening 148 in the hitch ball 12o.
The blocking arm 150 is inserted into the blocking arm opening 148 in the hitch ball 12o, and wrapped around the ball mount 40o, after the shank portion 34o of the hitch ball is inserted into the shank opening 46o of the ball mount. The engagement of the blocking arm 150 in the opening 148 of the hitch ball 12o, when the blocking arm is wrapped around the ball mount 40o, blocks rotation of the hitch ball relative to the ball mount. After the nut 50o is tightened, the blocking arm 150 can be removed. The blocking arm is not limited to the configuration or shape of the embodiment illustrated in
Claims
1. A hitch assembly comprising:
- a hitch ball;
- a ball mount;
- an aperture defined within the ball mount for receiving the hitch ball; and
- a recessed portion extending from the aperture; wherein a surface of the hitch ball extends into the recessed portion of the aperture to prevent rotational movement of the hitch ball relative to the ball mount.
2. A hitch assembly according to claim 1 wherein the ball mount has an upper side surface and a lower side surface and a thickness defined between the upper side surface and the lower side surface; and wherein the aperture passes through the entire thickness and the recessed portion passes partially through the thickness.
3. A hitch assembly comprising:
- a hitch ball;
- a ball mount;
- an aperture defined within the ball mount for receiving the hitch ball;
- a recessed portion extending from the aperture; and
- a fastener having a surface that extends into the recessed portion to prevent rotational movement of the fastener relative to the ball mount.
4. A hitch assembly according to claim 3 wherein the ball mount has an upper side surface and a lower side surface and a thickness defined between the upper side surface and the lower side surface; and wherein the aperture passes through the entire thickness and the recessed portion passes partially through the thickness.
5. A hitch assembly comprising:
- a hitch ball having a portion that is selectively movable; and
- a ball mount adapted to receive the hitch ball; wherein the selectively movable portion of the hitch ball is selectively engageable with a portion of the ball mount to prevent rotational movement of the hitch ball relative to the ball mount.
6. A hitch assembly according to claim 5 wherein the hitch ball has an end surface and the selectively movable portion extends beyond the end surface.
7. A hitch assembly according to claim 5 wherein the selectively movable portion is movable between a raised position and a dropped position.
8. A hitch assembly comprising:
- a hitch ball assembly;
- a ball mount adapted to receive the hitch ball assembly;
- wherein the ball mount has a portion that is selectively movable and is selectively engageable with a component of the hitch ball assembly to prevent rotational movement of the component of the hitch ball assembly relative to the ball mount.
9. A hitch assembly according to claim 8 wherein the ball mount has an upper side surface and the selectively movable portion extends beyond the upper side surface.
10. A hitch assembly according to claim 8 wherein the ball mount has a lower side surface and the selectively movable portion extends beyond the lower side surface.
11. A hitch assembly according to claim 8 wherein the selectively movable portion is movable between a raised position and a dropped position.
12. A hitch assembly according to claim 8 wherein the selectively movable portion is movable between a raised position, a centered position and a dropped position.
13. A hitch assembly according to claim 8 wherein the selectively movable portion is a pin.
14. A hitch assembly according to claim 8 wherein the selectively movable portion is a threaded pin that can be threaded into a portion of the ball mount or removed from the ball mount.
15. A hitch assembly according to claim 8 further comprising a set screw that secures said selectively movable portion in a raised position and a dropped position.
16. A hitch assembly according to claim 8 further comprising a spring-biased detent that secures said selectively movable portion in a raised position and a dropped position.
17. A hitch assembly according to claim 8 further comprising a plurality of interference rings that secure said selectively movable portion in a raised position and a dropped position.
18. A hitch assembly according to claim 8 wherein the hitch ball assembly comprises a hitch ball and a fastener, the selectively movable portion of the ball mount is selectively engageable with a portion of the hitch ball to prevent rotational movement of the hitch ball relative to the ball mount.
19. A hitch assembly according to claim 8 wherein the hitch ball assembly comprises a hitch ball and a fastener, the selectively movable portion of the ball mount is selectively engageable with a portion of the fastener to prevent rotational movement of the fastener relative to the ball mount.
20. A hitch assembly comprising:
- a hitch ball; and
- a ball mount adapted to receive the hitch ball; and
- a fastener having a top surface and a portion that is selectively movable to a position extending beyond the top surface, the selectively movable portion of the fastener is selectively engageable with a portion of the ball mount to prevent rotational movement of the fastener relative to the ball mount.
21. A hitch assembly comprising:
- a hitch ball comprising an end surface and at least one
- pin opening defined within the end surface;
- a ball mount adapted for receiving the hitch ball; wherein the ball mount comprises an upper side surface and at least one pin opening defined within the upper side surface; and
- a pin that engages both the at least one pin opening in the hitch ball and the at least one pin opening in the ball mount, thereby inhibiting rotational movement of the hitch ball relative to the ball mount.
22. A hitch assembly according to claim 21 wherein the pin is affixed within the at least one pin opening defined within the hitch ball.
23. A hitch assembly according to claim 21 wherein the pin is affixed within the at least one pin opening defined within the ball mount.
24. A ball mount adapted to receive a hitch ball assembly;
- wherein the ball mount has a portion that extends from the ball mount and is selectively engageable with a component of the hitch ball assembly to prevent rotational movement of the component of the hitch ball assembly relative to the ball mount.
25. A ball mount according to claim 24 wherein the hitch ball assembly comprises a hitch ball and a fastener;
- wherein the portion extends upward from an upper side surface of the ball mount and is selectively engageable with a portion of the hitch ball to prevent rotational movement of the hitch ball relative to the ball mount.
26. A ball mount according to claim 24 wherein the hitch ball assembly comprises a hitch ball and a fastener;
- wherein the portion extends downward from a lower side surface of the ball mount and is selectively engageable with a portion of the fastener to prevent rotational movement of the fastener relative to the ball mount.
27. A hitch assembly comprising:
- a hitch ball; and
- a ball mount adapted to receive the hitch ball; wherein the ball mount has a lower side surface and a portion that extends beyond the lower side surface, and
- a fastener which is selectively engageable with said portion of the ball mount to prevent rotational movement of the fastener relative to the ball mount.
28. A hitch assembly comprising:
- a hitch ball;
- a ball mount adapted to receive the hitch ball; wherein
- the ball mount comprises a lower side surface and at least one pin opening defined within the lower side surface;
- a fastener for securing the hitch ball to the ball mount;
- wherein the fastener comprises a top surface and at least one pin opening defined within the top surface; and
- a pin that engages both the at least one pin opening in the hitch ball and the at least one pin opening in the ball mount, thereby inhibiting rotational movement of the fastener relative to the ball mount.
29. A hitch assembly according to claim 28 wherein the pin is affixed within the at least one pin opening defined within the ball mount.
30. A hitch assembly according to claim 28 wherein the pin is affixed within the at least one pin opening defined within the fastener.
31. A hitch assembly comprising:
- a hitch ball having a slot defined therein; and
- a ball mount adapted to receive the hitch ball; wherein the ball mount includes a protrusion that is received within the slot of the hitch ball to prevent rotational movement of the hitch ball relative to the ball mount.
32. A hitch assembly comprising:
- a hitch ball;
- a ball mount adapted to receive the hitch ball; and
- a blocking arm which engages with the hitch ball and the ball mount to prevent rotational movement of the hitch ball relative to the ball mount.
33. A hitch assembly according to claim 32 wherein the blocking arm is a member that unites with a portion of the hitch ball, and extends along a top surface, down a side surface and across a bottom surface of the ball mount.
34. A hitch assembly comprising:
- a hitch ball; and
- a ball mount adapted to receive said hitch ball; wherein
- said ball mount comprises an upper surface and a means located in said upper surface for engaging a portion of said hitch ball to prevent relative rotation of the hitch ball and the ball mount.
35. A hitch assembly comprising:
- a ball mount adapted to receive a hitch ball; and
- a fastener; wherein said fastener comprises a top surface and a means located in said top surface for engaging a portion of said ball mount to prevent relative rotation of the fastener and the ball mount.
36. A hitch assembly comprising:
- a hitch ball; and
- a ball mount comprising:
- i) an aperture through which a portion of the hitch ball is received and secured; and
- ii) a recessed portion that is shaped to receive a conformingly shaped portion of the hitch ball to prevent rotation of the hitch ball relative to the ball mount.
37. A ball mount comprising:
- an aperture defined by a circumferential surface and adapted for receipt of a portion of a hitch ball therethrough; and
- a recessed portion extending from said circumferential surface, said recessed portion shaped to receive a conformingly shaped portion of a hitch ball to prevent rotation of the hitch ball relative to the ball mount.
38. A hitch ball comprising:
- a ball portion;
- a flange portion extending from said ball portion;
- a shank portion extending from said flange portion; and
- an anti-rotational portion extending from said flange portion.
39. A hitch ball according to claim 38 wherein said anti-rotational portion is a pin.
Type: Application
Filed: Jun 8, 2004
Publication Date: Jan 6, 2005
Applicant: MASTER LOCK COMPANY (Oak Creek, WI)
Inventors: Christopher Irgens (Elm Grove, WI), Frank Scott (Milwaukee, WI), John Zapushek (Racine, WI), Rolf Hohmann (Menomonee Falls, WI), Mark Van Handel (Milwaukee, WI), Craig Kottke (Grafton, WI), Christopher Rohde (West Allis, WI)
Application Number: 10/709,947