Abstract:
An improved tiller restraining device is provided for attachment to the underside of a boat&#39;s tiller to selectively control the position of the tiller and rudder. The device features a specialized mechanical clutch that grips or releases a control rope, which runs through the clutch and is secured across the cockpit. The device is operated with one hand by moving an integrated clutch lever upward to release the rope and allow free tiller movement, or downward to engage the rope and restrict tiller movement. Inside the device, a spring acts on the lever to pinch and bind the rope against the openings where the rope passes through the clutch housing. The spring and lever are aligned so they toggle, enabling the clutch to remain either engaged or disengaged with no additional controls.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     FEDERALLY SPONSORED RESEARCH 
     Not Applicable 
     SEQUENCE LISTING OR PROGRAM 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention generally relates to the steering of boats, specifically to an improved mechanical device that allows a single-handed pilot to quickly and easily restrain the position of the tiller and rudder at the stern of a boat. 
     2. Prior Art 
     Most smaller boats, especially sailboats, are steered with a rudder at the stern that is pivoted by a long arm called a tiller. The tiller extends into the steering area, or cockpit, for the sailor or pilot to use. 
     When steering a boat single handedly, a sailor often needs to momentarily release the tiller to attend to other critical tasks, including changing sails, adjusting lines, preparing anchors, and retrieving needed articles from elsewhere on the boat. Without some method of restricting tiller movement, the rudder can quickly swing to one side or the other, causing the boat to veer off course with undesirable results. Conversely, with the tiller fixed in position, the boat may remain on course long enough for the sailor to complete a necessary task. 
     Sailors have addressed this problem in the past with varying degrees of success. Numerous solutions have been tried, ranging from elaborately-tied ropes or elastic cords to rods and clamps. A few simple cord-based devices have been patented as shown by U.S. Pat. No. 4,480,572 to Lauterbach (1984) and U.S. Pat. No. 5,335,616 to Tiesler (1994). The difficulty with these devices is that they occupy two hands for set-up or adjustment, and they cannot be released quickly or intuitively when necessary. Unfortunately, in windy, foul-weather or crowded conditions the ability to make a quick-steering adjustment can be crucial. 
     A number of rigid tiller restraining designs have been disclosed in U.S. Pat. No. 2,846,896 to Allen (1958), U.S. Pat. No. 3,279,410 to Young (1966), U.S. Pat. No. 4,178,869 to Turrentine (1979), U.S. Pat. No. 4,188,904 to Childress (1980), U.S. Pat. No. 4,476,800 to Gage (1984), U.S. Pat. No. 5,052,321 to Toniatti (1991), and U.S. Pat. No. 5,133,274 to Grant (1992). These devices employ a rod or wooden stick with one end mounted to a side of the boat and the other end adjustably attached to the tiller to hold it in position. Though somewhat effective, each of these contraptions would prove cumbersome and awkward to use within the crowded confines of smaller-sized boats that typically use tillers for steering. In particular, they can obstruct the use of several important ropes that require frequent monitoring within the cockpit. Additionally, when not in use, these awkward devices consume precious cockpit storage space, and they present an unsightly, incongruent effect on the neat lines of a sailing craft. 
     The more practical tiller control solutions employ a more compact mechanical device that is attached to the tiller and engages a small control rope strung across the steering area. The control rope is positioned so that the tiller glides along it when steering. The device restricts tiller movement by gripping the control rope at any chosen location along the arc of the tiller. Several such devices have been developed by others, but each has its shortcomings. 
     The majority of these products employ a tensioning spring-and-screw combination that applies friction directly to the control rope as it winds its way through the device. A few versions of similar design appear to be in the public domain including the Tiller-Tamer™ by Davis Instruments Corp (www.davisnet.com). Such a device can be useful, but has several disadvantages. First, it takes time to activate, as the knob must be rotated several turns to engage or disengage the control rope. For unrestricted steering, the user must fully unscrew the knob, thereby loosing any desired friction on the control rope. Often frustrated by this operational requirement, the user tends to leave the knob partially tightened and simply overpowers it for every steering adjustment. This use tends to wear on the control rope and allow the device to slip under normal water pressures acting upon the rudder. Even with the screw fully loosened, significant friction remains on the control rope as it rounds the three bends required by the tensioning apparatus. This friction detracts from the pleasurable feel of freely steering the boat. It also masks the natural feedback that the sailor feels from rudder pressures. This feedback is important for the sailor when trimming sails for varying conditions. Furthermore, the tensioning knob protrudes from the top of the device, where it has been known to dangerously snag critical ropes during quick sailing maneuvers. 
     To address some of these issues, U.S. Pat. No. 4,080,918 to Bonhard (1978) shows a device which uses a hinged clamp to grip the control rope as it passes directly through it. This improved simple mechanism allows for faster engaging and complete releasing of the control rope, and it retains a pre-determined rope friction when disengaged. However, this product also falls short. The pilot must use one hand to engage it, while using the other hand to steer. Therefore, two hands and visual attention are required when attempting quick steering adjustments. This requirement can detract from the pilot&#39;s focus on boat direction, sails, etc. at a time when all are impacted by the steering action taken. Additionally, when disengaged, the hinged clamp part swings awkwardly away from the tiller, where it can snag the main sheet rope as with the previously mentioned device. This extended part can present a scraping hazard to the user, and can badly pinch a finger when closed in a hurry. 
     U.S. Pat. No. 4,241,684 to Davis (1980) discloses a device that addresses some of these issues in a unique, though problematic way. This device employs a set of opposing friction-operated cams to engage the control rope. One of the cams can tighten on the control rope in opposition to rope tension from the other side. The other cam performs the reverse action, so that the rope is restrained in both directions. A remotely located bicycle brake-type lever is provided with a cable to release the cams and free the control rope. Conceptually, this appears to be an improvement, since little effort is needed to engage the rope and the rope cannot slip from increased pressure on the tiller. However, in practice, this increasing grip could be hazardous because the cams would not yield to excessive rudder forces that could cause rudder failure. Likewise, a pilot could not overpower the device in an emergency. Furthermore, increasing tension on the control rope would make the cams increasingly difficult for the lever to disengage. To counter this release problem, the pilot would have to carefully offset any significant rudder load on the tiller before using the release lever. This requirement would diminish the convenience of the device and could slow steering reaction time. Finally, installation of the product onto the tiller is complicated by the attachment of the two separate components that require careful alignment for proper operation. 
     Other previous mechanical tiller restraining devices were not included in this discussion, but each of them attempts to provide a useful means of restraining the tiller while it is momentarily unattended. Nevertheless, each previous device fails to provide a fully satisfactory solution with regard to efficiency, convenience and safety, having several of the following disadvantages: 
     (a) Both hands are occupied to operate the device while steering. 
     (b) The operator must focus attention on the device to locate it and to operate it effectively. 
     (c) The device does not lend itself to one-handed, minor steering corrections while in use. 
     (d) Working the device requires repeated or complex hand motions to rotate an adjustment knob or work a clamp. 
     (e) The device restrains the tiller too securely, so the tiller cannot be forced by hand pressure, and will not yield to excessive underwater rudder pressure. 
     (f) An upwardly-protruding part of the device can entangle operating lines on the boat, and can present a hazard to the user. 
     (g) Residual friction in the control rope effects steering feel when the device is disengaged. 
     (h) Rigid poles or rods of the device are cumbersome and consume limited storage space when not in use. 
     (i) The mechanism presents a pinching hazard to the user. 
     (j) The device is ungainly and unpleasing to the eye. 
     Some of these disadvantages represent inconveniences, while others can slow reaction time and hinder boat operation, or become hazardous in rough conditions. 
     3. Objects and Advantages 
     Accordingly, several objects and advantages of the present invention are: 
     (a) To provide a tiller restraining device that is integrated into the normal steering position for one-handed operation, so that the pilot can grip the tiller handle and simultaneously restrict or un-restrict tiller movement; 
     (b) To provide a tiller restraining device that is intuitive in use, not requiring extra thought or wasted motion; 
     (c) To provide a tiller restraining device that allows one-handed, momentary release the for minor steering corrections; 
     (d) To provide a tiller restraining device that will instantly engage or release the control rope with a small motion of the fingers, even under load; 
     (e) To provide a tiller restraining device that can be predictably overpowered for emergencies, yet will not slip under normal working loads; 
     (f) To provide a tiller restraining device with a low profile that is secured beneath the tiller without upwardly protruding parts that could otherwise snag important sailboat lines, or cause a safety hazard; 
     (g) To provide a tiller restraining device that allows nearly frictionless steering when disengaged; 
     (h) To provide a tiller restraining device that is compact and can be permanently installed without taking up valuable space during use or storage; 
     (i) To provide a tiller restraining device that will not pinch the user&#39;s hand with normal use. 
     (j) To provide a tiller restraining device that is unobtrusive and aesthetically pleasing. 
     Further objects and advantages will become apparent from a consideration of subsequent description and drawings. 
     SUMMARY 
     In accordance with the present invention, a novel tiller restraining device is offered for boats steered with a conventional tiller arm. The heart of the device is a compact, spring-powered rope clutch attached to the underside of the tiller for selectively restraining it in any position along its arc of travel. The device places a small integral lever within the grasp of the pilot&#39;s hand. With this lever, the pilot can easily toggle the clutch mechanism to grip or release a control rope that passes through it and is fastened across the steering area of the boat. With a quick click, the tiller is either secured in place via rope friction, or released for free movement. Compared to the prior art, this invention exhibits improved speed, safety, efficiency, convenience, and aesthetics. In addition, the simplicity and minimal force required to operate it makes it user-friendly. 
    
    
     
       DRAWINGS 
       Figures 
         FIG. 1  is a partial perspective view of a boat showing the tiller restraining device installed and in use within the cockpit area of a boat. 
         FIG. 2  is an enlarged perspective view of the boat tiller restraining device attached to the handle portion of a boat tiller. 
         FIG. 3  is a sectional view on the line  3 - 3  of  FIG. 2 . 
         FIG. 4  is a sectional view on the line  4 - 4  of  FIG. 3 . 
         FIG. 5  is a variation of the sectional view in  FIG. 3  showing a refinement consisting of a spring adjuster. 
         FIG. 6  is a variation of the sectional view in  FIG. 3  showing an alternate embodiment having a spring adjuster and a lever stop pin. 
         FIG. 7  is variation of the sectional view in  FIG. 3  showing an alternate embodiment having a spring adjuster and a lever stop pawl. 
     
    
    
     DRAWINGS 
     Reference Numerals 
     
         
           10 . Boat showing cockpit area with tiller restraining device installed-assembly 
           12 . Cockpit area of boat 
           14 . Tiller arm that controls the rudder 
           16 . Rudder 
           18 . Tiller Restraining Device-assembly 
           20 . Control Rope 
           22 . Handle section of tiller 
           24 . Lever 
           24   a  Handle Arm of Lever  24   
           24   b  Load Arm of Lever  24   
           26 . Rivet Pin through Block  44   
           28 . Rivet Pin through Lever  24   
           30 . Plastic Bushing 
           32 . Mounting Screw 
           34 . Circular Passage for Control Rope  20   
           36 . Rounded Groove in mounting surface 
           38 . Cutaway in Housing 
           40 . Housing, hollow body 
           42 . Rectangular Aperture extending through Housing  40   
           44 . Spring Retaining Block 
           46 . Flat Spring (shown edge-on) 
           48 . “V” notch in Lever Load Arm  24   b    
           50 . Indexing Pin 
           52 . “V” notch in Block  44   
           54 . Mounting Screw Hole in Block  44   
           56 . Mounting Screw Hole in Housing  40   
           58 . Mounting Screw Hole in Housing  40   
           60 . Slot through Lever Load Arm  24   b  for mounting screw 
           62 . Shallow Recess in Lever Load Arm  24   b    
           64 . Slot in Block Part  40  to accept Rivet Pin  26   
           66 . Protective Spring Seat in “V” Notch  48   
           68 . Protective Spring Seat in “V” Notch  52   
           70 . Screw Knob 
           72 . Adjustable Spring Retaining Block 
           74 . Widened Screw Slot 
           76 . Back Wall in Housing 
           78 . “V” Notch in Block  72   
           80 . Screw Knob 
           82 . Spring Support Notch 
           84 . Spring Support Notch 
           86 . Stop Notch in Lever  24   
           88 . Stop Pin 
           90 . Spring 
           92 . Stop Pawl 
           94 . Spring 
           96 . Housing, modified 
           98 . Lever modified from preferred Lever  24   
       
    
     DETAILED DESCRIPTION 
     Preferred Embodiment—FIGS.  1 ,  2 ,  3 ,  4  and  5   
     A preferred embodiment of the present boat tiller restraining device  18  is generally illustrated in perspective view  FIG. 1 . A sailboat  10  having a cockpit  12  is equipped with a pivotally mounted rudder  16  to control the direction of travel. The rudder  16 , in turn, is controlled by a tiller arm  14  having a handle section  22 , which is held by the helmsman or pilot when steering the boat. A small control rope  20  spans the cockpit  12 , and is attached at each end to the sides of the boat  10  near the stern, meaning the back, or aft end of the boat. This rope may be fastened to the boat sides by any conventional means, such as a rope cleat, screw eye, padeye, shackle, etc. The rope  20  passes through a tiller restraining device generally designated  18 , which is fixed to the underside of the tiller  14  near its handle section  22 . 
       FIG. 2  is an enlarged perspective view of the tiller restraining device  18 , which has a generally rectangular, elongate hollow body or housing  40  with a full-length rectangular aperture  42  passing through it in an orientation forward to aft (rearward), with respect to the boat, and containing the internal working components of the device. In other words, the housing is generally constructed as a thick-walled rectangular tube. This housing could be made in other, more rounded hollow shapes, even as a hollow tube or it could be made as a chassis with appendages to support the working parts. 
     Also shown in  FIG. 2 , the forward end of the aperture  42  in the housing  40  contains a lever  24  that is rotatably secured with a rivet pin  28 . This pin is inserted horizontally through the side walls of the housing  40  near the forward lower end of the aperture  42 , and is oriented perpendicularly to the tiller  14 . The forward protruding portion of the lever  24  is shaped as a small, flattened handle for manipulation by the pilot. 
       FIG. 3 , a sectional view on the line  3 - 3  of  FIG. 2 , illustrates the internal components of the tiller restraining device  18 . Internal to the device, the lever  24  extends rearward or aft beyond the pin  28  to form the short load arm  24   b . This load arm terminates in a centered horizontal aft facing “V”-shape notch  48 . The top surface of the load arm  24   b  contains a shallow recess  62 . Above the load arm  24   b  and parallel to the pin  28 , a small circular rope passage  34  transects the sidewalls of the housing  40 , and is bisected by the aperture  42 . The rope  20  passes through this rope passage  34  to be acted on by the load arm  24   b . The lever  24  is positioned relative to the rope passage  34  so that the load arm  24   b  may be rotated upward between the bisected parts of the rope passage  34 . With the lever in this position, the surface of the shallow recess  62  will contact the rope  20 . 
     A single-leaf spring or slightly arched flat spring  46  applies force to the lever. A coil spring, a fiber and resin composite or a compressible elastomer spring could be used here with the same function. This spring lies in a generally horizontal position within the device. The “V” notch  48  supports and centers the forward end of the spring. The aft end of the spring  46  is held within an opposing “V” notch  52  furrowed into a spring retaining block  44 . This block  44  is fixed in place within the aft end of the housing  40  by a second rivet pin  26  through the housing, which passes through a slot  64  in the upper surface of the block  44 . Note that these “V” notches could have different shapes to accommodate other spring types. 
     A cutaway  38  in the lower forward end of the housing  40  partially exposes a reinforced pivot section of the lever  24 . Thin “V”-shape stainless steel spring seats  66  and  68  shield the softer material of the lever load arm  24   b  and the block  44  from the working ends of the hardened spring. A small indexing pin  50  resides within the center of the notch  48 . This pin is held within a shallow bore centered on the axis of symmetry of the lever  24 . The indexing pin engages a small notch centered within the forward end of the spring  46  to prevent lateral slippage of the spring and subsequent scraping of the side walls of the housing  40 . 
       FIG. 3  also shows the components that allow the tiller restraining device to be securely attached to the tiller  14 . Two flat-head or oval-head wood screws or sheet metal screws  32  attach the device to the underside of the tiller  14  near its handle  22 . Alternatively, a user may attach the device to the tiller by metal bands or clamps that tightly encircle both the device and the shaft of the tiller. 
     To accommodate the mounting screws, the lever load arm  24   b  is transected by a short centered, vertical slot  60  to allow passage of the forward screw  32 . This slot is elongated to prevent screw contact as the lever rotates in its prescribed arc. Similarly, an oversized vertical bore  54  through the block  44  allows unobstructed passage of the aft screw  32 . The extra clearance compensates for any misalignment of the block due to variations in dimensions. Countersunk bores  56  and  58  in the lower surface of the housing  40  center the screws  32  in the device. A shallow, rounded groove  36  ( FIG. 2 ) extends the length of the top mounting surface of housing  40  to enable secure seating to tillers of round or square cross section. 
     For protection against the corrosive marine environment, a careful choice of materials is needed. In the preferred embodiment, the housing  40 , lever  24 , and block  44  are machined from custom aluminum alloy extrusions with anodized and sealed surfaces. However, other materials could be used, such as reinforced molded plastic or cast bronze, stainless steel, etc. The pins  26  and  28  are made of stainless steel for strength and corrosion resistance to prevent wear and galvanic corrosion. In the preferred embodiment, Flat spring  46  is made of hardened stainless steel, but it could also be made of carbon steel, bronze, compressible elastomers or a fiber and resin composite. A small, flanged plastic bushing  30  prevents metal-to-metal contact between the pin  28  and the lever  24 , with the bushing&#39;s flange acting as a lateral thrust bearing for the lever  24 . 
       FIG. 4  is a sectional view on the line  4 - 4  of  FIG. 3 . This view specifically shows the engagement of the rope  20  with the rope passage  34  and the lever  24 . The mounting groove  36  is evident as it allows the housing  40  to be soundly seated against a tiller handle of circular section. Alternatively, the flat surfaces adjacent to the groove  36  would are designed to securely seat to the surface a rectangular tiller handle. 
     As a refinement to this preferred embodiment, the initial compression of the spring  46  can be made adjustable as shown in cross section in  FIG. 5 . The refinement involves making block  44  ( FIG. 3 ) adjustable in a forward-aft direction, which is shown as block  72 . The same basic shape and function of the previous block  44  (of  FIG. 3 ) is retained. It closely fits to slide within the rectangular aperture of the housing  40  and supports the end of the spring  46 . However, no rivet is used to fix the position of the adjustable block  72 . Instead, the housing has an integral back wall  76  enclosing the block  72  within the housing. An adjustment screw with an integral knob  70  is threaded horizontally through this wall to contact the aft surface of the block  72 . The screw knob is positioned to drive the altered block  72  forward to increase spring compression, or to allow spring force to drive the block aft. A widened slot  74  through the block  72  allows sufficient sliding movement of the block before it encounters the mounting screw  32 . 
     OPERATION 
     Preferred Embodiment—FIGS.  1 ,  2 ,  3 ,  4  and  5   
     Referring to  FIG. 1  and  FIG. 2 , the present tiller restraining device  18  provides a compact mechanism, which is essentially a unique toggling rope clutch. The mounting is simplified, requiring just two screws  32  to attach it to the underside of the boat&#39;s tiller  14 . However, the device is made to allow for attachment with clamps or bands. The device is positioned with the lever  24  facing forward immediately below the handle portion of the tiller  22 . This configuration enables the pilot to easily reach it with just two or three fingers while steering. The user friendly operation involves intuitive motions of the lever to engage or release the control rope  20 , which is fastened across the cockpit  12 . When the mechanism is engaged, it will not slide over the taut control rope  20 , and the tiller  14  and rudder  16  are restrained in their current positions. 
     Basic user operation is as follows: 
     Beginning with the device engaged and the pilot of the boat holding the tiller handle in the normal steering manor, a light squeeze of the handle  24   a  of the lever  24  upward toward the tiller handle momentarily releases the rope  20  for quick course adjustments. Simply releasing the lever re-engages the rope to quickly fix the boat on a corrected course. For continuous free steering, a stronger squeeze of the fingers toggles the lever to remain in the disengaged position after letting go. A light downward pressure of a finger behind the lever toggles the device to re-engage the control rope and restrain the tiller again. This convenient and intuitive action exceeds the utility and speed of the prior art. However, the complexity of the system has been reduced to surprisingly few multi-functional parts. 
     Referring to  FIG. 3 , the heart of this steering accessory is a novel clutch mechanism designed to grip or release the rope  20  that passes through it. In basic function, the lever alternately compresses or relaxes the spring  46  using the corresponding spring force to alternately grip the rope  20  and maintain the “engaged” mode or to release the rope  20  and maintain the “disengaged” mode. With the rope gripped or engaged, the device is prevented from sliding over the rope. Thus, with the rope tied in place, it in turn holds the tiller in place. Naturally, when the rope is disengaged, the device is free to slide over the rope and the tiller moves freely as well. 
     In detail, the lever  24  pivots about its pin  28  under load from the flat spring  46 . The lever operates within the aperture  42  of the hollow housing  40 . The rope passage is bisected by this hollow space, so that the lever&#39;s load arm  24   b  can swing through the interior space, where the rope passage penetrates the side walls of the housing. With the rope in place, the load arm can encounter the rope and pinch it between the upper edges of the load arm and the upper interior edges of the rope passage. With enough spring force acting on the lever, this double pinching action is sufficient to grip the rope and prevent tiller slippage under normal rudder loads. 
     To provide the needed force, the spring  46  is preferably an arched flat spring, which is easily produced to exact specifications, and which terminates in straight edges that are easy to confine while being allowed to pivot under load. However, other spring types can be used successfully, as mentioned earlier. In this unique application, the flat spring functions in compression by bowing and building spring force as its ends are slightly compressed together. Simple V-shaped notches ( 48  and  52 ) confine and control the ends of this spring. 
     With respect to the boat, the forward-facing notch  52  in the block  44  confines the rearward or aft end of the spring  46 . This block prevents vertical movement of the spring end, allowing it only to pivot within the notch. The opposing notch  48  that forms the end of the load arm carries the forward end of the spring  46 . This spring end travels up and down precisely with the lever  24  as it swings in its prescribed arc. Throughout this arc, the flat spring  46  remains confined and also compressed to varying degrees. The simplified precision of this arrangement allows for the clean toggling action that makes this device so effective. 
     The toggling action, in turn, relies on precise geometry. The lever  24  can rotate through an arc between two stopping points within the housing. At one stopping point, the handle of the lever  24   a  is in its uppermost position, and the opposing load arm  24   b  is pressed downward against the lower wall of the housing  40 . At the opposite stopping point, the handle is lowered, and the load arm is pressed upward to pinch the rope. In an intermediate position along its arc, the lever becomes aligned with both ends of the spring  46  due to the positioning of the involved components. In this position, the syitem is balanced and the spring&#39;s rotational leverage is neutralized. As the lever is manually rotated in either direction from this balance point, the spring&#39;s leverage can progressively increase. As this happens, increasing force is imparted to the lever to drive it on to the corresponding stopping point. In essence, spring leverage reverses as the lever is flipped from one stopping point to the next, thereby providing the toggling effect. 
     A special advantage of this mechanism is diminishing, rather than increasing, user effort. With a typical lever acting against a spring, increasing force is needed to depress the lever against the increasing counterforce of the spring. Here, however, spring leverage opposing the user diminishes as the lever is rotated toward the balance point, so effort needed by the user diminishes accordingly. Furthermore, when passing the balance point, the spring actually assists the user as its leverage is reversed and the lever is forced onward to the next stopping point. Hence, the user applies an initial effort that quickly diminishes until the lever clicks itself unassisted into the next position. 
     The geometry of this toggling clutch mechanism is finely tuned to maximize ease of use and mechanical efficiency. To this end, as the lever travels along its arc, its balance point is set to occur farthest from the point of rope contact. Since spring leverage increases as the lever rotates away from the balance point, the rope holding force is increased as well. However, this engagement offset is limited to prevent excessive elongation of the bowed flat spring and a loss of spring force. In this way, rope holding power is maximized, so that a reasonably light-duty spring may be used. Such a spring is very user-friendly. 
     When the device is disengaged, the offset balance point also helps the user re-engage it. Since this lever position is closer to the balance point, the spring has minimal leverage to resist the user. This means that minimal finger pressure is needed to re-engage the device. This light-touch engaging force is especially beneficial, since this action involves pressing the lever downward with the flick of a finger. Conversely, the somewhat greater effort needed to disengage the device is easily overcome, as the user can apply a few fingers with a more powerful gripping motion. 
     The refinement of including the offset balance point also helps with quick steering adjustments. When the pilot needs to quickly correct course with the device engaged, a full cycle of toggling to release and again to re-engage is unnecessary. From the engaged position, the lever has further to travel before it reaches the offset balance point. This extra travel makes it easy for the pilot to momentarily release the rope without toggling the clutch. Thus, after adjusting the tiller position, the lever may simply be released to spring back into the engaged position again. 
     In summary, the present tiller restraining device clearly provides a more convenient, quick, and intuitive steering restraint solution than taught by prior art. Still, several refinements are included in the present tiller restraining device to enhance its performance and make it completely user friendly. 
     In the preferred embodiment, to minimize friction when disengaged, the outward facing edges of passage  34  are rounded to allow the rope  20  to feed smoothly through it from any oblique angle. Conversely, the interior edges of the rope passage  34 , which are used to pinch and hold the rope, remain sharp to facilitate gripping efficiency. The “V” notches  48  and  52  that retain the ends of the spring  46  are formed as open right angles to retain the spring in a precise location, yet this construction avoids binding the spring at the extremes of lever movement. These deep V&#39;s also aid in assembly by guiding the spring into place. To further maintain precise spring alignment, the block  44 , which supports the fixed end of the spring, has an indexing mounting feature. The slot  64  in the upper surface of the block, which allows the pin  26  to secure it in place, has a sloping forward edge that acts to jam the block  44  against the lower wall of the housing  40  under spring pressure. This effect locks the block in place, thereby preventing any unwanted spring movement while the device is being operated. 
     Furthermore, to reduce user effort in working the lever  24 , substantial mechanical advantage is obtained with the ratio of the lengths of the handle arm  24   a  to the load arm  24   b  ranging from 2.5:1 to 4:1. The result is that the user experiences only a few pounds of effort to overcome the strong flat spring, which can generate over 15 pounds of friction resistance in the control rope. 
     Some of the refinements are for practicality. In  FIG. 4 , the versatility of the mounting groove  36  is evident as it allows the housing  40  to be soundly seated against a tiller handle of circular section. Alternatively, a rectangular tiller handle can contact the flat surfaces adjacent to the groove for a secure, flush fit. 
     Other refinements are included in the interest of safety. The mechanism is carefully designed to grip the control rope  20  with roughly 15 pounds of resistance to prevent slippage under normal boating conditions, yet at this holding level any crew can readily overpower the device without excessive force in an emergency situation. A substantially greater holding resistance could be difficult to overpower and could also contribute to rudder damage as it would not yield to the lateral force of a large wave impact. Another safety feature is the cutaway  38  in the lower forward end of the housing  40 , which eliminates a potential pinching hazard between the housing and the lever  24 . Furthermore, all edges of the device are well rounded for user comfort and to minimize injury from bumps and bangs typical of life aboard a moving boat. 
     To improve performance and convenience, the toggling mechanism is precisely balanced. The relative positions of the lever pivot pin  28  and the spring support notch  52  with respect to the rope passage  34  and housing  40  are carefully arranged to facilitate the optimum holding and toggling forces and stopping points for the lever  24 . This precise arrangement places the balance point of the lever closer to its disengaged position than to its engaged position. This offset, in turn, affords greater spring leverage and resulting holding force against the rope while engaged. For disengaging the device, the user&#39;s hand squeezes the lever upward toward the tiller handle. This powerful manual action easily overcomes the maximized holding force to release the rope. Conversely, the offset balance point produces a much lighter resistance to toggling the lever back downward for reengaging the rope. Thus, a light downward flick with the back of a finger can instantly engage, and restrain the tiller whenever needed. In refining the balance point, the depth of recess  62  has been adjusted to allow full rope contact before the lever bottoms out against the interior surfaces of the housing  40 , to maintain the full holding effect. 
     As an additional refinement, a spring force adjuster may be added to reduce lever effort when full tiller-holding power is not needed.  FIG. 5  shows an optional screw knob  70 , which can be rotated to allow the modified block  72  to slide slightly outward to relax the spring  46 . This minimal adjustment would be sufficient and more comfortable for the pilot when sailing in light conditions. In heavier weather, the knob could be re-tightened to fully compress the spring for maximum rope grip as designed. 
     DESCRIPTION 
     Alternative Embodiment—FIGS.  6  and  7   
       FIG. 6  shows a cross section of an alternative embodiment of the present invention. Here, the modified lever  98  has a shape and function similar to that of the preferred embodiment so that it may be pivoted to obstruct the rope passage  34 . However, the internal portion of the lever is enlarged near the lower surface of the housing  96 , where it has a downward-facing stop notch  86 . A spring-loaded stop pin  88 , retractable by force from a small spring  90 , penetrates the underside of the housing. The stop notch  86  is positioned to align with the stop pin  88  when the lever is moved nearly to its disengaged position. 
     Alternatively,  FIG. 7  shows a small pivoting, spring-loaded stop pawl  92  with a similar function. In  FIG. 6  and  FIG. 7 , a screw knob  80  is threaded upward through the underside of the housing  96  near the rearward or aft end of the spring  46 . The screw knob  80  is positioned and sized to be manually rotated until it contacts and displaces the spring  46 . The spring  46  is supported in  FIG. 6  and  FIG. 7  by the support notch  84  on the aft end of the lever and by the rear support notch  82 , which is fixed and integral to the housing  96 . Construction and materials are the same as for the preferred embodiment. 
     OPERATION 
     Alternative Embodiment—FIGS.  6  and  7   
     The two versions of an alternative embodiment shown in sectional views  FIG. 6  and  FIG. 7  function similarly to the preferred embodiment. The pilot manually squeezes the lever against spring force to disengage the rope and allow free steering. The primary difference is that the lever and flat spring arrangement do not toggle. Instead, the flat spring  46  is situated to only force the lever into the rope-gripping position. When the lever is squeezed and released, it will return to the engaged position. 
     To keep the lever disengaged from the rope when released by the pilot, an additional feature is included. With the lever fully squeezed upward into the released position, the stop pin  88  of  FIG. 6  or stop pawl  92  of  FIG. 7  may be pressed upward so that it engages the stop notch  86  in the lever  98 . As the lever is released, it is bound in place by the stop pin or stop pawl, which is, in turn, bound within the notch by the force of the lever. The lever will then remain disengaged from the rope to allow normal steering. When the lever is again squeezed by the pilot, the pin or pawl becomes unbound, and its small spring withdraws it from the notch in the lever. Then, as the pilot releases the lever, it is released to return to the engaged position. A tiny tab (not shown) on the interior edge of the pin or pawl prevents complete retraction and loss of the small part. 
     In these alternative embodiments, gripping power on the rope is made adjustable by means of the screw knob  80 . The screw knob contacts the spring close to the aft support notch  82 , so that screwing the knob inward torques the spring upward, increasing the bow over the length of the spring. This bowing increases spring pressure at its other end where it contacts the lever. Conversely, unscrewing the knob reduces pressure to the lever. With this adjustability, the screw may be set for a lighter gripping force for mild sailing conditions and easier lever work, or for a progressively firmer gripping force for increasing weather conditions. Since the lever releases the rope independently of the screw knob setting, a desired setting is never lost by disengaging the rope. 
     CONCLUSION, RAMIFICATIONS, AND SCOPE 
     Accordingly, the present invention provides a highly reliable tiller restraining device that enables the pilot of a boat to instantly, single-handedly and safely secure its tiller in any position, and further, to make quick adjustments as a natural part of the steering process. The advantages of this device can prove vital in crowded or rough conditions, when quick actions are necessary. 
     While the above description contains many specificities, these should not be construed as limitations on the scope of the invention but rather as exemplifications of the presently preferred embodiments thereof. Many other ramifications and variations are possible within the teachings of the invention. For example, on the internal end of the lever, the shallow recess that engages the control rope can be enlarged to completely encircle the rope, or even be made as a separate part acted on by the lever while exhibiting the same pinching effect to the rope. The housing could be made as a simple frame or base with appendages to support the working parts. The dimensions given pertain to the preferred embodiment, but other sizes and dimensions may be applied to the invention without altering its unique function, as long as the relative geometry remains consistent. Also, the parts could be made of different materials including reinforced plastics, fiberglass or other metals. Further, the device could be mounted elsewhere on a boat to control slippage of the rope for other purposes, including restraining the position of an outboard motor. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, and not be limited by the examples given.