The present invention relates to mechanical locks, and particularly to a radially reciprocating lock for easy and secure locking of mechanical components.
Many shafts, spindles, joints and pins incorporate keys to lock the same with another mechanical component, such as gears. This insures that the shaft does not dislodge from engagement with the connected mechanical component during movement thereof (e.g., that the gear rotates with the shaft), especially for rotary components. In most instances, the key is a relatively permanent element, both in fit and construction. As components wear or fail, it can be difficult to replace or remove those components from the keyed shaft.
Other mechanical constructions, such as locks that selectively connect parts together, also utilize a type of keyed engagement between the parts. Some examples include simple dead locks, reciprocating locks, and spring locks. These function well, but some tend to be overly complicated or difficult to operate. Others require specialized tools for actuating the locking mechanism. Still others have a narrow range of applications due to design and strength limitations, e.g., biased detents used in telescoping legs.
In light of the above, there is still a need for a relatively simple, durable lock that poses minimal difficulty in the operation thereof and has universal utility. Thus a radially reciprocating lock solving the aforementioned problems is desired.
The radially reciprocating lock includes an elongate, hollow, cylindrical housing having a locking mechanism disposed therein. The locking mechanism includes an axially extending lock shaft and at least one crank disk attached to the shaft. A recess is formed on at least one end of the lock shaft for insertion of a key or tool to rotate the lock shaft and the crank disk. At least one endcap is provided to securely cover an exposed end of the housing. The endcap includes a center hole for passage of the lock shaft end. At least one locking member is operatively connected to the crank disk to radially reciprocate between an extended, locked position and a retracted, unlocked position through respective slots on the housing. A crank linkage mechanism and a cam mechanism are provided to reciprocate the at least one locking member.
These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
The radially reciprocating lock, a first embodiment of which is referred to by the reference number 10 in
As best seen in
Referring to
As an alternative to the above-described configuration, one or both of the endcaps 26 can protrude past the plane of the end face 13 and/or have a larger diameter for easier access to the recess 24. Although not shown, an O-ring can be provided between the interior diameter of the bore 16 and the rim of the end caps 26 to seal the end openings of the bore 16 and further secure the mounting of the endcaps 26 therein. In this embodiment, it is more preferred to utilize lock pins or dowels 17 for insertion into aligned lock apertures 15 in the end caps 26 and the housing 12. This arrangement securely attaches the endcaps 26 to the housing 12 and prevents the endcaps 26 from rotating therein.
The locking mechanism 20 includes a pair of spaced crank or cam disks 28 mounted along the length of the lock shaft 22. The crank disks 28 each include at least one bore or hole 23 disposed at a position radially offset from the axis of the crank disk 28. The bores 23 support an elongate crank pin 21 therebetween, the crank pin 21 being supported by the disks 28 parallel to the lock shaft 22. One end of a crank arm, link, or member 25 is rotatably mounted to the crank pin 21. The crank arm 25 can also be referred to as a connecting rod, link or member. The crank arm 25 may be configured as an extruded oblong member having lateral bores 27 extending axially through the arm 25. As shown most clearly in
The locking member 30 may be configured as an elongate oblong block having a pair of lugs 32 depending from the bottom thereof. The lugs 32 straddle the opposite ends of the crank arm 25, and the pivot pin 29 is inserted through the bores in the lugs 32 and one of the lateral bores 27 in the crank arm 25. A slot 14 is formed on the housing 12 having the same shape as the locking member 30. The slot 14 defines a passage that restricts the movement of the locking member 30 into and out of the housing 12 in the radial direction. One or more sides of the locking member 30 can be provided with a sloping face 31 that allows easy radial reciprocation of the locking member 30 in the slot 14.
In use, the user inserts a key or tool into the recess 24 on one of the endcaps 26 and turns the tool, thereby rotating the lock shaft 22. From a retracted, unlocked position of the locking member 30, rotation of the lock shaft 22 in either direction over a certain degree of arc correspondingly pivots the crank arm 25. Due to the pivoted connection with the locking member 30, pivoting of the crank arm 25 pushes or reciprocates the locking member 30 in the passage in the slot 14, similar to a piston in an internal combustion engine, thereby extending the locking member 30 out of the housing 12 into the locked position. Preferably, referring to
An alternative embodiment of a radially reciprocating lock 100 is shown in
As shown in
In use, rotation of the lock shaft 22 via a tool or key inserted into the recess 24 causes radially reciprocating movement of the locking members 130 into and out of the housing 112 corresponding to the unlocked and locked positions of the radially reciprocating lock 100. The plurality of locking members 130 provides a very secure locking engagement at multiple points with respect to connected mechanical components. Moreover, the plurality of locking members 130 provides redundant backup for added insurance in case of mechanical failure of one of the locking members 130. Furthermore, the plurality of locking members 130 permits multiple components to be locked around the housing 112.
A further alternative embodiment of the radially reciprocating lock 200 is shown in
As best seen in
The locking mechanism 220 includes the elongate lock shaft 222 having a crank disk 228 rigidly attached thereto. The crank disk 228 is sized to fit and rotate inside the bore 216 in the housing 212. A recess or keyhole 224 is formed at the end of the lock shaft 222 for selectively receiving a key or a tool therein. In this embodiment, the recess 224 is configured to receive a hex-head tool or Allen wrench.
The locking function is facilitated by a pair of locking members 230 slidably mounted inside a bore 214 extending transversely through the housing 212. Radial extension and retraction of the locking members 230 correspond to locked and unlocked positions of the locking members 230. In this embodiment, the locking members 230 are constructed as elongate, cylindrical posts sized to completely retract within the housing 212 in the bore 214. It is to be noted that the locking members 230 can be constructed in any cross-sectional shape. An elongate cam follower, post or bar 232 extends orthogonally from one end of each locking member 230. The cam followers 232 are configured to slide within cam slots 221 upon rotation of the crank disk 228. In this embodiment, the cam slots 221 extend in a chordal line, rather than a radial line. It is noted that the cam slots 221 can be configured with any cam profile to facilitate the extension or retraction of the locking members 230, and particularly that the cam slots 221 may be straight (linear) or curved (arcuate).
As best seen in
The above features and functions of the radially reciprocating lock 200 work well in most situations, but in some instances, it may be necessary to positively lock the extended or retracted positions of the locking members 230. Therefore, the radially reciprocating lock 200 can include at least a pair of position-locking holes 223 disposed on the crank disk 228 and a selectively insertable position locking pin 225. The position-locking holes 223 are angularly spaced and offset from the axis of the crank disk 228. The positions of the position-locking holes 223 correspond to the rotated positions of the crank disk 228 for maintaining either the extended or the retracted positions of the locking members 230. Once either position has been reached, the user inserts the locking pin 225 through a lock hole 227 in the endcap 226 into one of the locking holes 223 aligned with the lock hole 227. Since the endcap 226 is stationary with respect to the rotatable crank disk 228, the aligned holes 223, 227 provide a positive and visual indication that the desired positions have been reached. The inserted locking pin 225 prevents any further rotation of the crank disk 228. The locking pin 225 can be threaded to match internal threads in the locking holes 223 and/or the lock hole 227 for positive installation of the locking pin 225. The locking pin 225 can also include a tool recess 229 to facilitate selective tightening or loosening of the same.
Referring to
Additionally, the radially reciprocating lock 300 includes a coiled spring 340 wrapped around the lock shaft 322. The coiled spring 340 includes end extensions, one extension being braced against the interior wall of the housing 312 and the other extension being braced against a stop post 342 disposed on the crank disk 328. This arrangement of the coiled spring 340 biases the locking members 330 into the extended, locked position. To unlock, the user simply rotates the crank disk 328 counter to the bias of the coiled spring 340, thereby retracting the locking members 330. The locking members 330 will spring back into the locked position upon release of the unlocking torque on the crank disk 328.
In the embodiment shown in
Additionally, the radially reciprocating lock 400 includes a plurality of leaf springs 440 for biasing the locking members 430 into the extended, locked position. Each leaf spring includes one end rigidly attached to the crank disk 428 and an opposite, free end 444. The free end 444 is braced against a stop post 442 attached to the interior wall of the housing 412. Due to the space occupied by the stop posts 442, the endcap 426 can include a grooved section 419 to accommodate the stop posts 442 when assembled. To unlock, the user simply rotates the crank disk 428 counter to the bias of the leaf springs 440 thereby retracting the locking members 430. The locking members 430 will spring back into the locked position upon release of the unlocking torque on the crank disk 428.
A further alternative embodiment of a radially reciprocating lock 500 is shown in
As best seen in
In contrast to the previous embodiments, the radially reciprocating lock 500 includes an elongate lever or handle 540 extending radially from the circumferential side of the crank disk 528. In this embodiment, the lever 540 is constructed as an elongate, circular post. It is to be realized that any geometric shape can be used in construction of the lever 540. Instead of the tool or key recess in the previous embodiments, the user can manipulate the lever 540 in an arc in order to turn the crank disk 528. The lever 540 extends out of an arcuate slot 542 in the housing 512. The length of the arcuate slot 542 defines and limits the movement of the lever 540 between locked and unlocked positions.
The lever 540 permits the locking and unlocking actuation of the radially reciprocating lock 500 from the side, rather than the axial end. This is particularly effective in securely connecting ends of pipes or the like, as best seen in
A still further alternative embodiment of a radially reciprocating lock 600 is shown in
As shown, the radially reciprocating lock 600 includes a cylindrical housing 612, a pair of locking members 630 extendable into and out of the housing 612 between unlocked and locked positions respectively, a cam follower 632 attached to each locking member 630, a crank disk 628 and a pair of cam slots 621 facilitating slidable movement of the cam followers 632 upon rotation of the crank disk 628. In this embodiment, each cam slot 621 is curvilinear, rather than straight. Each cam slot 621 includes a straight, chordal section 650 and a curved section 652 concentric with the circumference of the crank disk 628. The chordal section 650 pushes and pulls the respective cam follower 632 between the locked and unlocked positions. However, the curved section 652 permits further rotation of the crank disk 628 to seat the cam follower 632 into the end of the curved section 652. In this position, the respective locking members 630 are effectively locked into the locked position, since the cam follower 632 cannot begin to slide into the retracted, unlocked position until the cam follower 632 has at least reached the juncture between the chordal section 650 and the curved section 652. Thus, this arrangement provides a self-locking function without the need of springs or other components, although they can be incorporated as redundant features.
It is to be noted that the radially reciprocating lock 10, 100, 200, 300, 400, 500, 600 encompasses a variety of alternatives. For example, the radially reciprocating lock can be constructed from various materials, such as plastic, metal, wood, composites and combinations thereof. The individual components can be machined or molded, and they can be provided in various colors or with indicia for easy identification. Additionally, any of the abovementioned cam slots 221, 331, 431, 521, 621 can be configured to have curved cam profiles or a combination of linear and curvilinear profiles to facilitate the desired movement of the respective locking members.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/706,642, filed Sep. 27, 2012.
Number | Date | Country | |
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61706642 | Sep 2012 | US |