Patent Description:
Rescue tools known as "Jaws of Life" type devices are specialized tools used by various rescue personnel such as police, firemen and paramedics generally for the purpose of extricating accident victims from vehicles whose exits have been rendered inoperative. These tools require spreading and closing forces for opening or ripping apart inoperable doors or for cutting through relatively thick metal layers. Pushing or pulling forces of <NUM> to <NUM> kN (<NUM>,<NUM> to <NUM>,<NUM> pounds) at the tips are considered to be normal for the proper operation of such tools.

A rescue tool of the present type is shown and described in <CIT> and <CIT> of Hickerson. In those patents, there can be seen a rescue tool that is battery powered and which is capable of high torque spreading and cutting motion of its jaws. While very useful and an improvement in its time, the rescue tool of those patents can be improved upon by reducing its weight to make the device easier to handle and by increasing its efficiency as to heat dissipation so as to lengthen the life of the motor.

Accordingly, it would be advantageous to have a portable rescue tool that can carry out the functions of the rescue tools described in the aforementioned U. Patents but which has increased efficiency, lower weight, is less expensive to manufacture and has improved heat dissipation.

Another rescue tool is disclosed in <CIT>, in which a portable rescue tool having a pair of arms that are opened and closed by rotating a threaded member which can be connected to an external source of power, such as an electric motor, via a bevel gear arrangement.

Now, in accordance with a first aspect of the present invention, there is provided a power subassembly for use with a portable spreader tool, as set forth in the accompanying claim <NUM>.

The brake thereof directly contacts and provides a braking force to the motor shaft where the braking is the most effective. The brake brakes the motor shaft when the power to the motor is terminated and allows the motor shaft to rotate freely when the motor is being energized.

The associated portable spreader tool is readily manipulated by the user by providing, according to certain embodiments, a rubber grip located just adjacent to the proximal end of the motor housing and a handle bar that is angled slightly forwardly toward the working end of the portable spreader tool so that the user can have a firm, balanced hold on the portable spreader tool and can manipulate the portable spreader tool to carry out the desired operation.

Other features of the present portable rescue tool will become more apparent in light of the following detailed description of a preferred embodiment thereof and as illustrated in the accompanying drawings.

Referring now to <FIG>, there is shown an exploded view of the portable rescue tool <NUM> constructed in accordance with the present invention. As can be seen, the portable rescue tool <NUM> basically comprises a motor <NUM>, an angle rotary gearbox <NUM> and a main rotary actuator <NUM>. As can be seen, the motor <NUM> is contained with a motor housing <NUM> and a housing end cap <NUM> covers the proximal end <NUM> of the motor housing <NUM> and can be secured thereto by screws.

An electrical cable <NUM> passes through the housing end cap <NUM> to supply election energy to the motor <NUM>. The electrical cable <NUM> also passes through a rubber grip <NUM> that can be gripped by the user in order to carry out the manipulation of the portable rescue tool <NUM>.

The source of the electrical power can be a battery, not shown, and may be a variety of voltages, however, in the exemplary embodiment, the motor <NUM> is a <NUM> volt D. motor to be compatible with automobile or truck batteries.

In the embodiment of <FIG>, the motor <NUM> has pins <NUM> (only one of which is shown in <FIG>) that enter into slots <NUM> in the motor housing <NUM> and covers <NUM> can be secured to the motor housing <NUM> by means such as screws <NUM> to cover the slots <NUM>.

At the distal end <NUM> of the motor housing <NUM>, the angle rotary gearbox <NUM> has an output shaft <NUM> emerging therefrom and, as will be later explained, the rotational axis of the output shaft <NUM> is generally at a right angle with respect to the longitudinal rotational axis of the motor <NUM>. A sprocket <NUM> is located at the free end of the output shaft <NUM>.

A handle <NUM> is affixed to the external circular motor housing <NUM>. The handle <NUM> has an internal circular flange <NUM> that conforms to, and is affixed to, the exterior circular configuration of the motor housing <NUM> and has an external circular handle bar <NUM> that can be gripped by the user. When assembled to the motor housing <NUM>, the handle bar <NUM> is tilted slightly forwardly for the convenient gripping and manipulation by the user.

As such, the user can readily manipulate the portable rescue tool <NUM> by grasping the circular handle bar <NUM> with one hand and the rubber grip <NUM> with the other hand and move the portable rescue tool <NUM> to the desired orientation for its desired use.

As also can be seen in <FIG>, the main rotary actuator <NUM> is affixed to the motor housing <NUM> by means of an upper plate <NUM> and a lower plate <NUM> with the main rotary actuator <NUM> sandwiched therebetween. At the lower end of the main rotary actuator <NUM>, there is an input shaft <NUM> that is rotatable to operate the main rotary actuator <NUM>. A sprocket <NUM> is affixed to the free end of the input shaft <NUM> and a drive coupling <NUM> couples the output shaft <NUM> of the angle rotary gearbox <NUM> to the input shaft <NUM> of the main rotary actuator <NUM>.

In the exemplary embodiment the drive coupling <NUM> can be a single chain belt <NUM> that connects between the sprocket <NUM> on the output shaft <NUM> of the angle rotary gearbox <NUM> and the larger sprocket <NUM> at the free end of the input shaft <NUM> of the main rotary actuator <NUM>.

One of the sprocket <NUM> on the output shaft <NUM> or the larger sprocket <NUM> on the input shaft <NUM> of the main rotary actuator <NUM> may include a slip mechanism that is commercially available and one supplier is Martin Sprocket & Gear, Inc. of Arlington, TX. The mechanism is a torque limiting clutch where a driven member slips when a torque overload is present. Typically, the activation of the torque limiting clutch makes a clicking sound when operational and thus the user is alerted that the torque overload is present and the mechanism is effectively limiting the torque.

A gearbox retainer <NUM> is also included to strengthen the connection between the lower plate <NUM> and the lower end of the angle rotary gearbox <NUM> and a bottom cover <NUM> encloses and protects the drive coupling <NUM>.

The main rotating actuator <NUM> includes two rotating actuators <NUM>, <NUM> that rotate with respect to each other either toward each other or away from each other depending on the rotational direction of the motor <NUM>. Each of the rotating actuators <NUM>, <NUM> has two pairs of aligned connecting holes, that is, upper holes <NUM> and lower holes <NUM>. Only the upper and lower connecting holes <NUM>, <NUM> on the rotating actuator <NUM> are shown in <FIG>, however, similar holes are present on the other rotating actuator <NUM>.

The purpose of the aligned upper and lower connection holes <NUM>, <NUM> are to connect actuator arms (not shown in <FIG>) , that are used to pry or cut material by selectively having the actuator arms close towards each other or move away from each other in the normal operation of a portable rescue tool.

Atop of the main rotating actuator <NUM> is a clutch mechanism <NUM> that controls the rotational movement of the main rotating actuator <NUM> with respect to the upper and lower plates <NUM>, <NUM>, that is, the clutch mechanism <NUM> either allows the main rotating actuator <NUM> to rotate within the upper and lower plates <NUM>, <NUM> or prevents that rotational movement.

The clutch mechanism <NUM> is comprised of a relatively few components and is therefore light so as to enhance the maneuverability of the portable rescue tool <NUM> and allows the main rotary actuator <NUM> to rotate with respect to the fixed upper and lower plates <NUM>, <NUM>. As can be seen, the clutch mechanism, comprises a clutch plate <NUM> that is non-rotatably affixed to the main rotary actuator <NUM> by means, such as tabs <NUM> that extend outwardly from the clutch plate <NUM> and which engage slots <NUM> formed on the upper surface of the main rotary actuator <NUM>.

A clutch housing <NUM> is positioned atop of the upper plate <NUM> and can be firmly affixed thereto by screws or the like such that the clutch housing <NUM> does not move with respect to the upper plate <NUM>. A clutch material (not shown) is provided on the inner, downward surface of the clutch housing <NUM> and a screw <NUM> is centrally located and passes though the clutch plate <NUM> and extends upwardly through the clutch housing <NUM> where it is captured by a threaded knob <NUM>. Intermediate the clutch plate <NUM> and the clutch housing <NUM> is a friction disc <NUM>.

Accordingly, to operate the clutch mechanism <NUM>, the threaded knob <NUM> can be rotated by the user so as to tighten the clutch plate <NUM> against the clutch housing <NUM> such that the friction therebetween prevents the clutch plate <NUM> from rotating and it becomes fixed with respect to the clutch housing <NUM>. Since the clutch plate <NUM> is keyed to the main rotary actuator <NUM> through the tabs <NUM> and slots <NUM>, the main rotary actuator <NUM> is prevented from rotating with respect to the upper and lower plates <NUM>, <NUM>.

If the user wants to move the rotational position of the main rotary actuator <NUM>, the threaded knob <NUM> is simply unscrewed from the screw <NUM>, thereby releasing the clutch plate <NUM> and allowing the main rotary actuator <NUM> be rotated to the desired orientation and the threaded knob <NUM> again tightened to retain the main rotary actuator <NUM> in the desired position.

As such, the threaded knob <NUM> can be employed by the user to allow the rotational movement of the main rotating actuator <NUM>. Thus, the clutch mechanism <NUM> locks the position of the main rotating actuator <NUM> in a positive manner, requiring relatively few parts, thereby reducing the overall weight and allowing the main rotating mechanism <NUM> to rotate in both directions.

Turning then to <FIG>, there is an exploded view illustrating the power subassembly of the motor <NUM> and the angle rotary gearbox <NUM> within the motor housing <NUM>. As can be seen in <FIG>, the motor <NUM> is located in the proximal end <NUM> of the motor housing <NUM> such that pins <NUM> enter into and are located within the slots <NUM>. A motor mount ring <NUM> is positioned distal to the motor <NUM> within the motor housing <NUM> to mount the motor <NUM> therein. As also shown, a motor shaft <NUM> extends outwardly from the motor <NUM> and connects the motor <NUM> to the angle rotary gear box <NUM>. The motor <NUM> and motor shaft <NUM> have a longitudinal axis of rotation.

The angle rotary gear box <NUM> reduces the motor speed at a ratio of about <NUM>:<NUM> so that the characteristics of the output shaft <NUM> is one of low speed, high torque output. The motor shaft <NUM> can be seen to directly couple to the angle rotary gearbox <NUM>, thereby improving efficiency and reducing the weight of further coupling components. To also improve efficiency, it can also be seen that the angle rotary gearbox <NUM> directly receives the rotational movement of the motor <NUM> and changes the direction of the longitudinal axis of rotation of the motor shaft <NUM> to the rotational axis of the output shaft <NUM> of the angle rotary gearbox <NUM>. In the exemplary embodiment, that angle is about <NUM> degrees.

There is also an electrically powered brake <NUM> that surrounds the motor shaft <NUM> and is held therein by means of a mount <NUM> that mounts the brake <NUM> as well as the angle rotary gearbox <NUM>. The brake <NUM> is electrically powered and is biased to its locked position preventing the motor shaft <NUM> from rotating, however, when power is applied to the brake <NUM>, and also the motor <NUM>, the brake <NUM> is released and the motor shaft <NUM> is free to rotate.

Thus, the subassembly of the motor <NUM> and angle rotary gearbox <NUM> is a compact structure, readily assembled and removable from the other components of the portable rescue tool <NUM> and includes a minimum of components so as to minimize the weight to facilitate the manipulation and use of the portable rescue tool <NUM> by a user. The motor <NUM> is directly coupled to the angle rotary gearbox <NUM> and the angle rotary gearbox <NUM> delivers the high torque rotational energy. The brake <NUM> is located directly on the motor shaft <NUM> since less braking is needed at the motor shaft <NUM> than at other locations.

Turning then to <FIG>, there is a side cross sectional view of the portable rescue tool <NUM>. In <FIG>, there can be seen the overall portable rescue tool <NUM> and illustrating the position of the motor <NUM> that has a longitudinal rotational axis that is generally horizontal as depicted in <FIG> and the output shaft <NUM> of the angle rotary gearbox <NUM> has an axis of rotation that is generally at a right angle with respect to the axis of rotation of the motor <NUM>.

A toggle switch <NUM> is provided in a location near the proximal end <NUM> of the motor housing <NUM> so as to be readily accessible to the user. By conventional wiring, the toggle switch <NUM> is connected between the electrical cable <NUM> and the motor <NUM> to energize and de-energize the motor <NUM> as well as to change the direction of rotation.

Turning then to <FIG>, taken along with <FIG>, there is shown a perspective view of the portable rescue tool <NUM> of the present invention. As such the angle rotary gearbox <NUM> is illustrated, as well as the motor housing <NUM> that encloses the motor <NUM>. The electrical cable <NUM> extends outwardly from the proximal end <NUM> of the motor housing <NUM> and includes the rubber grip <NUM> that is located just adjacent to the proximal end <NUM> of the motor housing <NUM> for gripping by the user. The user can also grip the handle bar <NUM> that, as can be seen, is angled away from the proximal end <NUM> of the motor housing <NUM> and thus toward the working end of the portable rescue tool <NUM>.

Accordingly, both the rubber grip <NUM> and the handle bar <NUM> are conveniently located to enable the user to grip and manipulate the portable rescue tool <NUM>.

As also can be seen in <FIG>, the knob <NUM> is located atop of the main rotating actuator <NUM> for retaining and releasing the main rotating actuator <NUM> for rotational movement.

In <FIG>, there can also be seen, actuator arms <NUM>, <NUM> that extend outwardly from the rotating actuators <NUM>, <NUM>, respectively, such that the distal ends <NUM>, <NUM> are moved by means of the rotating actuators <NUM>, <NUM> to move the distal ends <NUM>, <NUM> in opposite directions, that is, the distal ends <NUM>, <NUM> can be forced together to carryout a cutting action or spread away from each other for creating a space between components of, for example, an automobile in gaining access thereto.

Finally, in <FIG>, there is a perspective view, partially cut away, of the main rotating actuator <NUM>. The main rotating actuator is commercially available and can be the same as that shown and described in the aforementioned <CIT> and <CIT> of Hickerson.

Basically, the main rotating actuator <NUM> is comprised of a housing <NUM> and which is flanked by the rotating actuator <NUM>, <NUM>. The input shaft <NUM> passes though the housing <NUM> and a main gear <NUM> is affixed thereto and rotates along with the input shaft <NUM>. Main gear <NUM> rotates a set of four follower gears <NUM> (only two of which are shown in <FIG>). The follower gears <NUM> are affixed to secondary shafts <NUM> having planetary gears <NUM> (again, there are two sets of planetary gears <NUM>).

The planetary gears <NUM> drive inner gears <NUM> internal of each of the rotating actuators <NUM>, <NUM> to move those rotating actuators <NUM>, <NUM> either toward each other or away from each other in the operation of the portable rescue tool <NUM>.

Claim 1:
A power subassembly for use with a portable spreader tool (<NUM>), the subassembly comprising:
an electric motor (<NUM>) having a motor output shaft (<NUM>) with a first axis of rotation,
an angle rotary gear box (<NUM>) operably coupled to the electric motor (<NUM>) and adapted to receive rotary motion from the electric motor (<NUM>) and provide a low speed, high torque rotary output at an output shaft (<NUM>) having a second axis of rotation oriented about <NUM> degrees from the first axis of rotation, and
an electrically powered brake (<NUM>) that acts directly on the motor output shaft (<NUM>) and which is selectively movable between a braking position wherein rotation of the motor output shaft (<NUM>) is restricted and a non-braking position wherein the motor output shaft (<NUM>) is rotatable.