Patent Publication Number: US-6986397-B2

Title: Power riding trailer for an implement

Description:
RELATED APPLICATION 
   This application claims the benefit of U.S. provisional application No. 60/360,848, filed on Mar. 1, 2002, which is incorporated herein in its entirety by this specific reference. 

   FIELD OF THE INVENTION 
   The present invention generally relates to floor treatment equipment, and more specifically relates to a power riding trailer for use in controlling, for example a speed and direction of, a floor treatment implement. 
   BACKGROUND OF THE INVENTION 
   It is often necessary to sand or refinish large areas of flooring, such as basketball gyms, ballrooms or the like. In order to make this job easier and less time consuming, the use of riding trailers has been employed. Thus, the sander, e.g., a drum sander, or other implement is hitched or otherwise coupled to a trailer. A human being, sitting atop this trailer, controls both the trailer and the implement and, overall, gets the job done faster than if he/she had to walk behind the implement. 
   One such riding trailer or attachment is disclosed in Neitzer, Jr. U.S. Pat. No. 3,161,994. The Neitzer, Jr. riding attachment includes two propelling and supporting wheels mounted on an axle driven by an electrical motor through a drive assembly including belts, pulleys, a chain and sprocket. In addition, this attachment has a separate steering lever which is coupled to a caster on the sander. Thus, the operator of the attachment indirectly steers the sander by manipulating the steering lever on the attachment to steer the caster. This riding attachment has several drawbacks. For example, the relatively complex drive assembly between the electric motor and the axle may be prone to frequent breakdowns and may require substantial maintenance. In addition, the feature in which the sander is indirectly steered using a steering lever on the attachment reduces the amount of control of and “feel” for the sander the operator has. 
   Another riding trailer is disclosed in Mattson, U.S. Pat. No. Re. 34,822, which is incorporated herein in its entirety by this specific reference. The Mattson patent discloses a power riding trailer for an implement which utilizes a non-gasoline powered motor and a hydraulic transmission for propelling the trailer forward. 
   Although this prior art power riding trailer greatly facilitates floor treatment operations, there is a need for a relatively smaller, more conveniently sized power riding trailer that is more easily maneuverable and can be used in both large and small scale operations. A riding trailer of simpler construction which is capable of use in smaller residential rooms as well as larger commercial rooms would clearly be advantageous. 
   SUMMARY OF THE INVENTION 
   The present invention provides a vehicle or trailer apparatus, more particularly a riding trailer apparatus, useful for propelling and/or controlling a floor treatment implement. More particularly, the present invention relates to such an apparatus which is effective, simple and straightforward in construction, easy to operate, subject to reduced wear and tear and has reduced maintenance requirements. 
   A riding trailer apparatus in accordance with the present invention generally comprises a frame having a rear portion and a forward portion, an operator support platform coupled to the frame, a hook-up mechanism disposed on the frame forward portion and structured to enable a floor treatment implement to be operatively coupled to the apparatus, and a drive assembly structured to drive the apparatus, for example, while the apparatus is operative and coupled to the implement. More specifically, the drive assembly includes a powered wheel assembly, a drive unit operatively coupled to the powered wheel assembly, and an electronic controller operatively coupled to the drive unit and effective to enhance operator control of the drive unit. 
   In one particularly advantageous embodiment of the invention, the drive unit includes a motor, for example a bi-directional DC motor, and a gear assembly operably connected thereto. Preferably, the controller comprises an electronic cotroller, and is preferably effective to control at least one of a speed and a direction of the drive unit. Preferably, the controller includes an AC to DC converter (hereinafter “AC-DC converter”). In addition, the controller preferably further comprises a potentiometer, for example, a variable speed potentiometer operably connected to the drive unit and structured to control a speed of the drive unit. For example, the potentiometer is structured and adapted to control a speed of the motor in response to movement of an operator controlled foot pedal. 
   The drive assembly preferably further includes a convenient manually operable mechanism connected to the drive unit for initiating movement of the apparatus. For example, the manually operable mechanism comprises a foot pedal, for example, a foot pedal that is used to initiate start up and movement of the apparatus in either a forward direction or reverse direction. The foot pedal is preferably disposed at a convenient location relative to the operator support platform, for example, the foot pedal is disposed on a frame forward portion. 
   In one particularly advantageous embodiment of the invention, the electronic controller is structured to control a ground speed of the apparatus in both a forward direction and a reverse direction. Specifically, the controller preferably comprises no more than a single variable speed pot, or potentiometer, for controlling ground speed of the apparatus in both a forward direction and a reverse direction. Even more specifically, the controller comprises a single potentiometer operably connected to the drive unit, wherein the single potentiometer being structured to control a speed of the drive unit motor in both a forward and a reverse direction. In this embodiment the drive assembly further includes a cable assembly including a flexible cable connecting the potentiometer to the foot pedal, for example. 
   Advantageously, the drive assembly is structured and arranged such that the controller requires no more than a single potentiometer for controlling ground speed of the apparatus in both a forward and a reverse direction. 
   The apparatus may also include a non-powered wheel assembly, including for example one or more free rolling casters connected to the frame forward portion, for facilitating transport thereof. 
   The apparatus is preferably structured and sized so that a human being can rest, for example in a seated position, upon the operator support platform and easily control the implement coupled to the apparatus. The drive unit and the electronic controller are both sized and structured to be substantially entirely located beneath the operator support platform. The frame is preferably made of aluminum or other suitable strong, preferably lightweight material. The hook-up mechanism is structured to be highly versatile in that it can be easily adapted to operably connect the apparatus with one of a plurality of different types of conventional floor treatment implements, for example, but not limited to floor sanders, buffers, preparation, polishing and grinding machinery for concrete, marble and urethane surfaces, and other surface finishing implements. 
   Preferably, the drive unit is an electrically powered drive unit and is entirely powered using AC current. It preferably includes no hydraulic drive mechanism or gasoline powered motor. The drive unit and controller are preferably arranged and sized such that these components may be substantially entirely disposed beneath the operator support platform within the frame rear portion. 
   Advantageously, the electronic controller greatly enhances operator control of the apparatus. The controller preferably further includes a speed board, for example, a signal isolator board (“SIRC”) which provides isolation between the signal voltage source and the controller for operating and controlling the potentiometer. 
   In another particularly advantageous feature of the invention, a disengagement mechanism is structured and positioned to enable manual disengagement of the drive unit from the powered wheel assembly. The disengagement mechanism is designed to enable an operator of the apparatus to easily disengage the powered wheel assembly from the drive unit, such that the wheels may be freely rolled in a neutral position. Preferably, this feature includes an internal, differential lock out mechanism that is operable by means of an external lever disposed at a convenient location on the frame. This feature greatly facilitates transportation of the apparatus in a non-operating mode by allowing an operator to easily disengage the drive unit so that the apparatus may be easily rolled from one place to another on the same wheels that are used for driving the apparatus. 
   Generally, the apparatus of the present invention is substantially smaller in size and weight, for example, the apparatus is about one third to about one half of the weight and size of prior art riding trailers, for example the power riding trailer disclosed in Mattson, U.S. Pat. No. Re. 34,822. For example, in one embodiment of the present invention, the riding trailer apparatus weighs less than about 75 pounds and has a turning radius of about 3.5 feet. Despite its small size, the apparatus of the invention is capable of driving full-sized industrial sanders, buffers and other floor treatment and finishing implements. The relatively small size and/or light weight of the present apparatus, in comparison to otherwise functionally eguivalent systems, such as that disclosed in Mattson &#39;822, is made possible at least in part by the arrangement of the drive assembly and inclusion of the electronic speed board therein, in some of the systems of the present invention. 
   The relatively smaller size and power requirements of the apparatus of the present invention make the device ideal for small scale operations. For example, the apparatus may be suitable for residential use, for example for treatment of a floor in a room having a floor length of about ten feet or more. 
   Each and every feature described herein, and each and every combination of two or more such features is included within the scope of the invention provided that the features included in such combination are not mutually inconsistent. 
   The present invention and the objects and advantages thereof will be more clearly understood and appreciated with respect to the following Detailed Description, when considered in conjunction with the accompanying Drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a perspective view of a riding trailer apparatus in accordance with the present invention being used to propel a conventional floor sander implement. 
       FIG. 2  shows a schematic representation of a driving assembly of the riding trailer apparatus shown in FIG.  1 . 
       FIG. 3  shows a perspective view of a control cable connecting a foot pedal to a potentiometer of the apparatus shown in FIG.  1 . 
       FIG. 4  shows a rear portion of the apparatus shown in  FIG. 1 , including a differential lock out lever for disengaging a powered wheel assembly from the driving assembly. 
       FIG. 5  shows a perspective view of a riding trailer apparatus in accordance with the present invention being used to propel one of a variety of floor treatment implements. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Turning now to  FIG. 1 , a riding trailer apparatus for propelling a floor treatment implement, in accordance with the present invention, is shown generally at  10 . The apparatus  10  generally comprises a frame  14  having a rear portion  16  and a forward portion  18 , a powered wheel assembly  20  coupled to the frame  14 , an operator support platform  24  coupled to the frame  14 , and a hook-up mechanism  30  disposed on said frame forward portion  18  structured to enable a floor treatment implement  36  to be operatively coupled to the riding trailer apparatus  10 . 
   The operator support platform  24  may include a height adjustable seat  37  coupled to a post  37   a , or any other suitable arrangement. 
   In addition, turning now as well to  FIG. 2 , the riding trailer apparatus  10  further comprises a drive assembly  38  including a drive unit, preferably an electrical powered drive unit  40 , for propelling the powered wheel assembly  20 . The apparatus  10  preferably includes no hydraulic drive mechanism or gasoline powered motor. 
   The drive unit  40  includes a motor  44 , and gear box  46  having a gear reducer (not shown), which are both preferably contained in a compartment  47  located beneath the operator support platform  24 . The gear box  46  is coupled to a drive shaft  48  of the powered wheel assembly  20 . For example, the drive shaft  48  extends through the gear box  46  such as shown in FIG.  2 . In the embodiment of the invention shown, the powered wheel assembly  20  is located at the rear frame portion and includes two powered wheels  49  coupled to drive shaft  48 . 
   Preferably, the apparatus  10  of the present invention is entirely electrically powered using AC current. The motor  44  is preferably a conventional, bi-directional DC electric motor. The motor  44  and gear box  46  preferably are sized and structured to operate on about 2.7 amperes of power. The apparatus  10  preferably includes no hydraulic drive mechanism or gasoline powered motor. 
   Advantageously, the drive unit  40  includes a controller, specifically an electronic controller  52  that is structured to be effective in enhancing operator control and smooth, reliable operation of the apparatus  10 . The drive unit  40  and controller  52  are both preferably substantially entirely located beneath the operator support platform at the rear frame portion. 
   In a preferred embodiment of the invention, the controller  52  includes an AC-DC converter  54  (for example 180V DC), and is structured to be connected to an AC power source  55 . The AC-DC converter  54  provides a significant advantage to operation of the apparatus  10 , particularly during low end RPMs. Overall, the controller  52  provides a more constant output of power to the motor  44  than is available with prior art systems, for example. This structure and arrangement ensures a relatively smooth operation of the apparatus  10  without sharp stops and starts. 
   Preferably, the electronic controller  52  allows forward and reverse torque to the motor  44  in both speed directions in order to control and maintain constant speed, rapid instant reversing. In addition, the controller  52  preferably is structured to include means to protect against motor overload and enhances smooth starting even during rapid cycling of incoming AC current. For example, the controller  52  may comprise a regenerative motor drive, preferably a full wave, 4-quadrant regenerative motor drive such as the regenerative motor drive manufactured and sold by KB Electronics and having model no. KBRC-240D. 
   Once the apparatus  10  is turned on by means of switch  55   a , initiation of movement of the apparatus  10  may be provided by any suitable manually operable mechanism, preferably by means of a single foot pedal  56  disposed at a convenient location on the forward portion  18  of the frame  14  as shown in FIG.  1 . Preferably, the drive assembly  38  is structured and operable to enable an operator to initiate start up, direction and speed to the motor  44  entirely by means of the foot pedal  56  in order to leave the operator&#39;s hands free to operate and control the implement  36 . 
   Referring now to both FIG.  2  and  FIG. 3 , a potentiometer  60 , with voltage suitably applied thereacross as known in the art, generates a signal substantially proportional to the direction and angle of the foot pedal  56 . Preferably, the potentiometer  60  comprises a single potentiometer  60 , which is used to control the speed of the motor  44 , and for initiating, stopping and controlling speed of both forward and reverse driving of the powered wheel assembly  20 . 
   This may be accomplished, for example, by means of a cable assembly  66  connecting the foot pedal  56  to the potentiometer  60 , which is used to control the speed of the motor  44 , and for initiating, stopping and controlling speed of both forward and reverse driving of the powered wheel assembly  20 . 
   This is preferably accomplished by the cable assembly  66  shown most clearly in  FIGS. 2 and 3 . For example, the cable assembly  66  includes a flexible cable  66   a , coupling the foot pedal  56  and the potentiometer  60 . The foot pedal  56  is mounted to a mechanism  67   a , connected to one end of the cable  66   a , and the potentiometer  60  is mounted to a rotatable shaft  67   b , connected to an opposing end of the cable  66   a . The cable assembly  66  includes bracket elements  68  which secure the cable assembly  66  to the forward frame portion (not shown in FIG.  3 ). The cable assembly  66  includes springs  69 , or other suitable means for translating operator initiated motion of the foot pedal  56  to the rotatable shaft  67   b.    
   This arrangement of the foot pedal  56 , potentiometer  60  and cable assembly  66 , as substantially described and shown herein, enables the use of a single potentiometer  60  for controlling both forward and reverse speed of the apparatus  10 . Advantageously, in this embodiment of the invention, no additional potentiometers are required for controlling ground speed of the apparatus  10  in both a forward and a reverse direction. 
   In addition, the provision of the flexible cable  66   a , in this arrangement, rather than for example a rigid arm or other rigid mechanical linkage, greatly enhances the reliability and smoothness of operation of the apparatus  10 . The flexibility of the cable  66   a , allows easy, quick and accurate adjustment of the performance of the apparatus  10 , for example by facilitating adjustment of the response and sensitivity of the foot pedal. During assembly and maintenance of the apparatus  10 , precise adjustments to the smoothness and operator control of the apparatus  10  can be made by simply adjusting the length of the flexible cable  66   a , until desired performance level is reached. Overall, this arrangement is substantially more “user friendly” during both assembly and maintenance of the apparatus  10 . 
   In order to even further enhance reliable and smooth operation of the apparatus  10 , means are provided to isolate and/or amplify signals sent from the potentiometer  60  to the AC-DC converter. For example, an electronic speed board  78 , including a signal isolator, such as a SIRC (Model KBSI-240D, manufactured by KB Electronics), is used to isolate, amplify and condition DC voltage signals from the potentiometer  60 . It also provides an isolated input to control motor direction and an isolated power supply for operation of the potentiometer  60 . 
   Turning back to  FIG. 1 , electrical connection between the apparatus  10  and the implement  36  can be accomplished in a number of ways. For example, electrical power may be supplied directly from source  55  to controller  52  by means of line  80 , and is run through the apparatus  10  to power the implement  36  through line  81 . Alternative arrangements for running electrical power through the apparatus  10  and implement  36  are contemplated and are considered to be within the scope of the invention. For example, electrical power may be supplied to both the apparatus  10  and the implement  36  through separate AC lines. Alternatively, power may be supplied initially to the implement  36  and then to the apparatus  10  from an extension cord extending between the apparatus  10  and implement  36 . 
   In addition, referring now to FIG.  2  and  FIG. 4 , preferably the apparatus  10  further comprises a disengagement mechanism  86  for disconnecting the powered wheel assembly  20  from the drive unit  40 . Preferably, the disengagement mechanism  86  comprises a differential lock out mechanism which enables any operator to shift the drive unit  40  into a neutral position, thereby freeing the powered wheel assembly  20  and allowing the apparatus  10  to be manually maneuvered from place to place. A lever  90 , shown in  FIG. 4 , may be provided in a convenient location which connects to the internal differential lock out mechanism. Advantageously, when the powered wheel assembly  20  is placed in a neutral position, the apparatus can be rolled and maneuvered along ramps and through narrow passageways between rooms to be treated, without the need for an operator to manually “tip” the apparatus  10  onto casters  91 . 
   Turning to  FIG. 5 , the hook-up mechanism  30  of the apparatus  10  is preferably structured to enable a variety of different types of floor treatment implements to be operatively coupled to the apparatus, for example, but not limited to conventional floor refinishing equipment  150 , such as for example floor sanders, buffers, surface finishing implements, and concrete prep machinery. 
   This may be accomplished in a variety of ways. For example, as shown in  FIG. 1 , the hook up mechanism  30  may include connectors  92 , coupled to a ball joint hook-up mechanism  93 . Many other arrangements may be provided, with interchangeable hardware for accommodating various different types of implements. Such other arrangements can be devised by a person or ordinary skill in the art, and thus are not described in great detail herein. 
   Preferably, for connecting the apparatus  10  to a particularly heavy piece of equipment, such as, for example, a dual sander implement, one of more counterbalance elements  94 , for example weights of about 15 pounds, are provided. Such weights are structured and adapted may be removably attached to apparatus  10  at wheels  49 . In some cases, additional weights may be provided which are structured to be removably secured to the implement. 
   Other arrangements for connecting various floor treatment implements to the apparatus  10 , as will be known to those of skill in the art, are possible and are considered to be included within the scope of the invention. 
   As shown in  FIG. 2 , the apparatus  10  preferably includes a cooling fan  100  coupled to the incoming power source  55 . The apparatus  10  may optionally include an hour meter  102  for measuring and monitoring duration of time the apparatus  10  has been used for a particular job or application. 
   Advantageously, the apparatus  10  is sized and structured to be no greater than about 75 pounds (not including weight of any counterbalance elements  94 ), and thus is approximately only one-third to about one-half of the size and weight of a conventional riding trailer, for example the riding trailer disclosed in Mattson, U.S. Pat. No. RE. 34,822. 
   While this invention has been described with respect to various specific examples and embodiments, it is to be understood that the invention is not limited thereto and that it can be variously practiced within the scope of the following claims.