Extendable Baton With Locking Mechanism

Abstract

An extendable baton includes first and second telescoping tube sections, the first tube section having two inner circumferential grooves near one end. A cam assembly is carried by the second tube section for selectively locking the first and second tube sections to each other. The cam assembly includes two radially movable cams each having two lands and a groove therebetween. The two cams are movable radially relative to each other between a locked position in which the lands on the two cams are engaged in the grooves in the tube section, and an unlocked position in which the lands on the two cams are displaced radially inward from the grooves on the tube to enable relative axial movement of the first and second tube sections.

Description

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No. 63/004,855, filed Apr. 3, 2020, titled Extendable Baton With Locking Mechanism.

BACKGROUND OF THE INVENTION

This invention relates to an extendable baton. In these batons, two or more telescoping tube sections are provided, with a locking mechanism for locking the baton in an extended condition for use. The locking mechanism can be selectively unlocked, to collapse the tube sections and make a shorter baton for transport.

One example of this type of baton is shown in U.S. Pat. No. 8,721,459. This baton has a tube section with an internal groove that can receive two identical radially movable locking members or cams. A spring between the cams biases them radially outward. When the locking members are aligned axially with the groove, they expand outward into the groove, thereby locking the tube sections together. This locking engagement is released by pressing a rod end into openings in the centers of the locking members, causing the members to be drawn radially inward, out of the groove. This allows the tube sections to telescope inward, to enable collapsing of the extendable baton.

SUMMARY OF THE INVENTION

The present invention provides a new and improved locking mechanism for an extendable baton. In one embodiment, the invention relates to an extendable baton including first and second telescoping tube sections. The first tube section has two inner circumferential grooves near one end, spaced apart from each other by a first distance and having an inner circumferential rib between them. A cam assembly is carried by the second tube section for selectively locking the first and second tube sections to each other. The cam assembly includes two cams having alignment holes located therein. The first cam has a radially outer surface with two arcuate lands and a groove therebetween. The second cam has a radially outer surface with two arcuate lands and a groove therebetween. The lands on the second cam are spaced apart by the same distance as the lands on the first cam, which is equal to the first distance between the tube section grooves. The first and second cams are movable radially relative to each other between a locked position in which the lands on the two cams are engaged in the grooves in the tube section, and the rib on the tube is in the groove on the cams, blocking relative axial movement of the first and second tube sections, and an unlocked position in which the lands on the two cams are displaced radially inward from the grooves on the tube to enable relative axial movement of the first and second tube sections.

In one embodiment, an portion of the second cam has an insert portion that is received in an opening of the first cam thereby to interlock the first and second cams and block relative axial or tipping movement.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the invention will become apparent to one of ordinary skill in the art to which the invention pertains, from a reading of the following description of an embodiment of the invention together with the accompanying drawings, in which:

FIG. 1 is an axial sectional view of a baton that is a first embodiment of the invention, shown in a fully extended position;

FIG. 2 is an enlargement of a portion of FIG. 1 focusing on one of the cam assemblies;

FIG. 3 is an enlarged sectional view illustrating the cam assembly in a locked position;

FIG. 4 is a perspective illustration of the two cams in an expanded position;

FIG. 5 is a perspective illustration showing the two cams in a retracted position;

FIG. 6 is a sectional perspective view illustrating the cam assembly and tubes in an engaged and locked condition;

FIG. 7 is a view similar to FIG. 6 showing the view illustrating the cam assembly in an unlocked condition without having moved the tubes relative to each other;

FIG. 8 is a view similar to FIG. 7 showing the view illustrating the cam assembly in an unlocked condition and showing the tubes moved relative to each other; and

FIG. 9 is a view similar to FIG. 6 illustrating a second embodiment of the invention.

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

The present invention provides a new and improved locking mechanism for an extendable baton. The invention is applicable to batons and locking mechanisms of different constructions. As representative of the invention, FIG. 1 illustrates a baton 10 that is a first embodiment of the invention.

The baton 10 has three telescoping tubes: an outer tube or handle 12 with a handle cap 14; a middle tube 16; and an inner tube 18. The middle tube 16 carries at its proximal end (nearer the handle 14) a first cam assembly 20 (FIGS. 1 and 2) that is engageable with a pair of grooves 70 on the distal end of the outer tube 12. Each one of the tubes 14-18 is preferably made from one open right cylindrical piece of material such as aluminum or plastic. End caps may be provided on the tubes 14-18, as shown.

The inner tube 18 carries at its proximal end (nearer the handle 14) a second cam assembly 22 (FIG. 1) that is engageable with another pair of grooves 72 on the distal end of the middle tube 16. The second cam assembly 22 is functionally identical to the first cam assembly 20. A lock release rod 24 is also provided, of a known type.

The cam assembly 20 (FIGS. 1-3) includes two parts, or cams, that are physically different from each other but that are fitted together to form the cam assembly. The two cams are referred to herein as the outer cam or first cam 30 and the inner cam or second cam 50. A portion of the inner cam 50 is received inside the outer cam 30 as described below.

The outer cam 30 has an overall rectangular box shape including six walls that surround and define a central chamber. Two of the six walls, each designated 32 and located opposite each other, have aligned circular openings for 34 receiving the release rod 24. These two walls 32 extend radially when assembled and face axially up and down the length of the baton 10. Two other walls 36, which extend chordally in the baton tubes when assembled and face radially outward, are solid, that is, with no openings provided.

Of the remaining two outer cam walls 38 and 40, one wall (the upper wall 38 as viewed in FIG. 4) has an oval shaped opening 42. This opening 42 is dimensioned to receive an insert portion 54 of the inner cam 50, as described below.

The sixth and remaining wall 40 of the outer cam 30 (the lower wall as viewed in FIG. 4) is solid and is configured to engage with the grooves 70 in the tubes. Specifically, this lower wall 40 has two cam projections or lands 42 on opposite axial ends of the wall, with a notch 44 between the lands. The lands 42 are arcuate to match the inner circumference of the baton tubes.

The inner cam 50, as noted above, is different from the outer cam 30. The inner cam 50 has a cam portion 52 and an insert portion 54. The cam portion 52 of the inner cam 50 is similar in configuration to the lower wall 40 of the outer cam 30—two arcuate cam projections or lands 56 on opposite sides of a notch 58. The lands 56 of the inner cam 50 align axially with the lands 42 of the outer cam 30 when assembled, on opposite radial sides of the baton centerline.

The insert portion 54 of the inner cam 50 projects radially inward from the cam portion 52. The insert portion 54 has the same configuration as, and is shaped to fit closely inside of, the oval shaped opening 42 of the outer cam 30. The two cams 30 and 50 are thereby interlocked. The insert portion 54 has a circular opening 60 for receiving the unlock rod 24. The insert portion 54 of the inner cam 50 is slid able within the opening 42 of the outer cam 30, to enable radial expansion and contraction of the cam assembly 20 when it is assembled inside the baton 10. When assembled, the lands 56 on the inner cam 50 are located diametrically opposite the lands 42 on the outer cam 30.

The cam assembly 20 preferably includes spring pockets 62 as shown in FIGS. 4 and 5 that receive compression springs 64 to bias apart the two cams 30 and 50. Alternatively, repelling magnets can be used if spring weakening over time is an issue.

When the baton 10 is assembled, the first cam assembly 20 is carried in the proximal end portion of the middle baton tube 16 and thus moves with the middle tube. The outer tube 12 has two circular grooves 70 on its cylindrical inner side surface, that are the same distance apart from each other as the two pairs of lands 42 and 56 on the first cam assembly 20. A rib 74 is located between the two grooves 70.

The dimensions of the parts are selected so that when the outer tube 12 and the middle tube 16 are not locked (FIG. 8) , the lands 42 on the first cam assembly 20 are spaced apart axially (along the length of the baton 10) from the grooves 70 on the outer tube 12. The radially outer side surfaces of the lands 42 and 56 on the cams 50 and 50, respectively, are biased radially outward against the inner circumferential surface of the outer tube 12, and the cams are held in a radially inward position, as shown in FIG. 8.

When the middle tube 16 and the outer tube 12 are positioned axially relative to each other so that the first cam assembly 20 is aligned axially with the grooves 70 in the outer tube 12, that is, when it is located radially inward of the grooves 70, the cams 30 and 50 can move radially outward into the grooves, under the influence of the springs 64. The lands 42 on the first cam 30 and the lands 56 on the second cam 50 engage in the grooves 70. This position of the parts is shown in FIG. 6.

Specifically, the two individual lands 42 on the outer cam 30 are engaged in the two individual grooves 70 of the outer tube 12. On the circumferentially opposite side of the baton 10, the two individual lands 56 of the inner cam 50 are engaged in the same two grooves 70 of the outer tube 12. This engagement provides a locking engagement between the first cam assembly 20 and the outer tube 12. As a result, the middle tube 16 is locked with the outer tube 12.

Extendable batons like the baton 10 are of a generally standard length and diameter. Thus, the baton 10 is of generally the same length and diameter as the baton shown in the prior art U.S. Pat. No. 8,721,459 referenced above. In contrast, each cam assembly 20, 22 of the baton 10 is significantly longer (axially) than the single cams of the baton shown in U.S. Pat. No. 8,721,459. Because of this added length, the cam stability is greatly increased. There is significantly more surface engagement, in a direction extending along the axis, between the cam assembly and the tubes. This helps to stabilize the cams 30 and 50, minimizing cam roll, for example.

Further, the increased number of cam projections and grooves provides increased locking surface area. There are two cam projections or lands 42 and 56 on each cam 30 and 50, respectively, locked into two grooves 70, rather than just one. As a result, there are four radially extending cam side surfaces in engagement with four radially extending groove side surfaces, resisting axial movement, rather than just two. This feature increases locking surface area and thus locking strength of the baton 10.

Another benefit of the present invention arises from the fact that the oval-shaped insert portion 54 of the inner cam 50 is completely surrounded by the body of the outer cam 30, in the oval-shaped opening 42 of the inner cam 30. Thus, the two cams 30 and 50 are interlocked together at all times, and self-aligning. Sideways (axial) force on the cam assembly 20 will not separate the cams 30 and 50. This feature greatly increases cam stability as compared to a cam assembly in which the two cams are only side by side.

When the parts of the baton 10 are thus locked, the center hole 60 in the inner cam 50 is misaligned radially with the center hole 34 in the outer cam 30. To release (unlock) the middle tube 16 from the outer tube 12, the release rod 24 is pushed in so that its tip engages the surface defining the center hole 34 in the outer cam 30 and the surface defining the center hole 60 in the inner cam 50, forcing the two center openings to align by drawing the cams radially inward. This radially inward movement of the two cams 30 and 50 draws the cam lands 42 and 56 out of the grooves 70 in the outer tube 12 (FIG. 7). As a result, the middle tube 16 is no longer locked with the outer tube 12, and those two tubes can be collapsed relative to each other, as shown for example by the different position of the parts that is illustrated in FIG. 8.

A similar action occurs with the second cam assembly 22, which can selectively lock or unlock the middle tube 16 with the inner tube 18.

FIG. 9 illustrates a portion of a baton 10a that is a second embodiment of the invention. In the baton 10a, the locking grooves are formed in the tube end caps, rather than in the tubes themselves. This construction can be provided for ease of manufacture. In FIG. 9, parts of the baton 10a that are the same as or similar to corresponding parts of the baton 10 (FIGS. 1-8) are given the same reference numerals with the suffix “a” added for clarity.

Specifically, in the baton 10a (FIG. 9), an end cap 100 is screwed onto the distal end of the outer tube 12a. The end cap 100 has two inner circumferential grooves 70a. A cam assembly 20a is carried on the end of the middle tube 16a. When the middle tube 16a is extended from the outer tube 12a, the cam assembly 20a becomes positioned radially inward of the end cap 100. The cams 30a and 50a can then move radially outward into locking engagement with the grooves 70a. The releasable locking connection between the middle tube 16a and the inner tube (not shown) would be similar.

Thus, the present invention can be seen to encompass at least two physically different embodiments—with the locking grooves formed directly in the elongate tubes themselves, or with the locking grooves formed in a separate element (like the end cap 100) that is connected with the elongate tube. The term “tube section” as used herein encompasses both of these variations and others that are apparent to one of ordinary skill in the art.

From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. For example, the cam projections and grooves could have a shape that is different from the shape that is shown in the illustrated embodiment, to vary or increase engagement surface. Such options could include a triangular shape or a hexagonal shape. Also, more than two cam projections can be provided on each cam, with a correspondingly increased number of grooves. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.

Claims

1. An extendable baton comprising:

first and second telescoping tube sections, the first tube section having two inner circumferential grooves near one end, spaced apart from each other by a first distance and having an inner circumferential rib between them; and

a cam assembly carried by the second tube section for selectively locking the first and second tube sections to each other;

the cam assembly comprising two radially movable cams each having two lands and a groove therebetween;

the first and second cams being movable radially relative to each other between a locked position in which the lands on the two cams are engaged in the grooves in the tube section, and an unlocked position in which the lands on the two cams are displaced radially inward from the grooves on the tube to enable relative axial movement of the first and second tube sections.

2. A baton as set forth in claim 1 wherein the second cam has a cam portion and an insert portion, the cam portion of the second cam including the lands on the second cam, and the insert portion of the second cam slidably engaging in an opening of the first cam to provide relative sliding movement of the two cams in a radial direction between the locked position and the unlocked position.

3. A baton as set forth in claim 2 wherein the insert portion of the second cam has an oval shaped external configuration that is received in an oval-shaped opening of the first cam thereby to interlock the first and second cams and block relative axial or tipping movement.

4. A baton as set forth in claim 1 wherein the tube section includes an elongate cylindrical tube and the locking grooves are formed on the tube.

5. A baton as set forth in claim 1 wherein the tube section includes an elongate cylindrical tube with a separate cap and the locking grooves are formed on the cap.

6. An extendable baton comprising:

first and second telescoping tube sections, the first tube section having two inner circumferential grooves near one end, spaced apart from each other by a first distance and having an inner circumferential rib between them; and

a cam assembly carried by the second tube section, the cam assembly for selectively locking the first and second tube sections to each other;

the cam assembly comprising two cams having alignment holes located therein;

the first cam having a radially outer surface with two arcuate lands and a groove therebetween;

the second cam having a radially outer surface with two arcuate lands and a groove therebetween;

the locking lands on the second cam being spaced apart by the same distance as the locking lands on the first cam, which is equal to the first distance between the tube section grooves;

the first and second cams being movable radially relative to each other between: a locked position in which the lands on the two cams are engaged in the grooves in the tube section, and the rib on the tube is in the grooves on the cams, blocking relative axial movement of the first and second tube sections, and an unlocked position in which the lands on the two cams are displaced radially inward from the grooves on the tube to enable relative axial movement of the first and second tube sections.

7. A baton as set forth in claim 6 wherein the second cam has a cam portion and an insert portion, the cam portion of the second cam including the lands on the second cam, and the insert portion of the second cam slidably engaging in an opening of the first cam to provide relative sliding movement of the two cams in a radial direction between the locked position and the unlocked position.

8. A baton as set forth in claim 7 wherein the insert portion of the second cam has an oval shaped external configuration that is received in an oval-shaped opening of the first cam thereby to interlock the first and second cams and block relative axial or tipping movement.

9. A baton as set forth in claim 6 wherein the tube section includes an elongate cylindrical tube and the locking grooves are formed on the tube.

10. A baton as set forth in claim 6 wherein the tube section includes an elongate cylindrical tube with a separate cap and the locking grooves are formed on the cap.