Patent Publication Number: US-6340154-B1

Title: Motorized clamp device

Description:
BACKGROUND 
     The field of invention relates to clamping devices and spreader devices. Clamps of various designs and shapes are used for a variety of purposes. Typically they require manual adjustment to increase or decrease the width between the clamp ends. 
     Manual adjustment can be time consuming, tedious and fatiguing when the worker is required to open and close the clamp numerous times. Manual adjustment clamps can be especially burdensome when the worker must operate the clamp repeatedly during a short period of time. 
     Traditional clamp designs require that both hands of the operator be used to tighten and loosen the clamp. Often the operator has a need to use one hand for holding the object to be clamped. The requirement for holding the objects arises when a specific alignment is desired between the object and the clamp or when an object needs to be held stable as the clamp is applied. Specific alignment of the objects prior to clamping is particularly challenging when there are several objects to be aligned and clamped simultaneously. This can be very unwieldy, frustrating and time consuming for one operator to attempt to hold the objects and operate the clamp simultaneously. 
     The common alternative is for two operators to cooperate in the procedure, with one holding the object and the other operator applying the clamp. Once again, unnecessary expenses are incurred when two workers perform a clamping task that could be accomplished by one worker, if the appropriate clamping device were available. 
     Another draw back of traditional clamp designs is the slow operation of the clamp when being manually adjusted by the operator. This is a time consuming task to slowly increase or decrease the spacing between the clamp ends. The working hours lost in adjusting the clamp spacing can be particularly expensive when the objects being clamped vary significantly in size and the objects are changed with great frequency. 
     Clamping devices are used in many trades, including applications by framers, mechanics and carpenters. Picture framers have a requirement for applying two clamps at a 90 angle to the corner of a picture frame. The side pieces of the picture frame are glued together and the clamp is used to hold them securely while the glue hardens. The side pieces of the picture frame are angled so they press against one another when pressure is applied to each of them in the proper direction. The two clamps must both be tightened with approximately the same pressure at the same time or the alignment of the picture frame sides will be distorted. This operation requires alternating the tightening and turning procedure between the two clamps, while still holding one side of the picture frame in a fixed and aligned position against the adjacent side of the picture frame. This operation must be done subsequently for each of the four corners of the picture frame. There is a need for a clamping device that will simultaneously tighten two clamps with a minimum of physical effort, thus allowing the framer to focus his attention on the proper alignment of the picture frame. 
     Picture framers, mechanics and carpenters often spend many hours twisting and turning the clamping device during their daily routine. Some workers have developed carpal tunnel syndrome of their hands and wrists due to this repeated operation. A clamping device that reduces the physical effort would be of great medical benefit to these individuals. 
     The inadequacies of traditional clamp designs indicate there is a need for a clamping device that can be held with one hand, while being accurately adjusted with minimal physical effort. There is also a need for the clamp that provides quick adjustment for increasing or decreasing the spacing between the clamp ends. The clamping device should have the option of a foot operated switch that allows the hands to remain free. 
     SUMMARY 
     It is an object of the present invention, a motorized clamping device, to overcome the disadvantages of the traditional clamp designs. 
     An advantage of the motorized clamping device is its capability to quickly move the motorized adjustable clamp for increasing or decreasing the spacing between the clamp ends, through the use of a motor controlled by an activation switch or motor switch located on the device. The motor may include a variable speed mode or adjustable torque. The manual clamp may be fixed or a manual adjustment bar provides even greater flexibility in quickly adjusting the spacing between the clamps. 
     Another objective of the present invention is providing a tool that will function both as a clamp that applies pressure upon an object to adhere surfaces together and also function as a spreader, which applies force to spread apart and separate portions of an object. The motorized clamping device accomplishes this objective by having the motor housing removable and reversible, so that the contact surfaces now move away from each other thus acting as a spreader function. 
     The manual adjustment bar is provided with numerous selection points for adjusting the spacing. Multiple teeth creating a saw-tooth design is one method. The adjustment device can be located near the handhold, so there is minimal movement or wasted time is adjusting the manual adjustment bar. 
     By combining two clamp heads and two motors, the present invention satisfies the objective of a clamping device that will simultaneously tighten two clamps with a minimum of physical effort, thus allowing the picture framer to focus his attention on the proper alignment of the picture frame. 
     Another object of the invention is to have the motorized clamping device used as a vise attached to a workbench. This is accomplished through the use of a worm gear or a helical gear that allows the motor housing to be placed under or to the rear of the workbench, while the clamping jaws are on the top surface of the workbench. This arrangement avoids having the motor hanging on the end of the adjustable clamp as occurs in other applications. 
     Another advantage of the motorized clamping device is labor and time savings by allowing the operator to use only one hand to adjust the spacing between clamp ends. This is accomplished by placing the adjustment switch near the handle of the device. There is also a need for a motorized clamping device that provides quick adjustment for increasing or decreasing the spacing between the clamp ends without the use of either hand. The motorized clamping device may have the option of a foot-operated switch that allows the hands to remain free. 
     The motorized clamp device includes a motor housing having a first channel with a first motor movably positioned within the first channel. A motor control switch is attached to the motor housing. A first head is attached to and powered by the first motor. The first head has a first shaft and a first contact surface. 
     A first torque collar is attached to the motor housing. The first torque collar has a first aperture that receives the first shaft. There is a second contact surface attached to the motor housing. When the first motor causes the first shaft to rotate, the first shaft passes through the first aperture of the first torque collar and force is applied to an object by the first contact surface and the second contact surface. The first motor travels within the first channel as the first shaft passes through the first torque collar. 
     Attached to the first motor is a first motor collar that has a first ear, which is received by the first channel. When the first shaft rotates, the first ear is held within the first channel thus preventing the first motor from rotating within the motor housing. This causes the first shaft to move through the first torque collar and the first motor to move with the first shaft, the first motor moving back and forth within the first channel of the motor housing. 
     The motorized clamp device has a manual clamping bar that has an inner surface and a saw tooth edge. The saw tooth edge has a plurality of teeth. 
     The second contact surface is attached to the inner surface of the manual clamping bar and the motor housing receives the manual clamping bar. The object may be firmly secured between the second contact surface on the manual clamping bar and the first contact surface of the first head, when the first head is actuated and applies pressure to a portion of the article. 
     In a variation of the invention the first motor is a first bi-directional motor and a power source is attached to the motor housing for energizing the first bi-directional motor. The first bi-directional motor includes the capability to halt the forward movement of the shaft when a preset pressure is achieved upon the object. 
     An adjustment device can be added that controls the range of adjustment of the manual clamping bar, such that, the manual clamping bar is incrementally adjusted between the plurality of teeth by the adjustment device. 
     The manual clamping bar has a travel stop, such that when the travel stop comes into contact with the motor housing the travel stop limits the maximum distance of travel for the manual clamping bar. 
     The invention can be configured as a spreader where a second contact surface is attached to the outer surface of the manual clamping bar and the motor housing receives the manual clamping bar. When the first shaft passes through the first torque collar and exits the motor housing the first contact surface and the second contact surface increase the distance ‘d2’ between them. This increasing of the distance ‘d2’ creates a spreading effect. 
     Another version allows the invention to function for both spreading and clamping functions in the work place. The second contact surface is attached to the inner surface of the manual clamping bar. A third contact surface is attached to the outer surface of the manual clamping bar. The motor housing is removably attached to the manual clamping bar such that the motor housing may be removed from the manual clamping bar, be reversed and reattached to the motor housing. This allows the first contact surface to face about 180 degrees from the initial orientation of the first contact surface such that the first contact surface faces away from the third contact surface. 
     When the first shaft passes through the first torque collar and exits the motor housing the first contact surface and the third contact surface increase the distance ‘d2’ between them, creating a spreading effect. When the motor housing is in its initial position the object may be firmly secured between the second contact surface on the manual clamping bar and the first contact surface of the first head, when the first head is actuated and applies pressure to a portion of the article. 
     For picture frame assembly and other applications the motor housing has a second channel with a second motor movably positioned within the second channel. A second head is attached to and powered by the second The second head has a second shaft and the second contact surface is attached to the second shaft. A second torque collar is attached to the motor housing, the second torque collar having a second aperture that receives the second shaft. 
     A second motor collar is attached to the second motor, similar to the construction of the first motor collar with an ear and the first motor. The motor collar has a second ear and the second channel receiving the second ear. 
     The first shaft has a first axis running along the first centerline of the first shaft and a second axis running along the second centerline of the second shaft. The intersection of the first axis and second axis create an angle α that is less than a 180 degree angle, such that an opposing object receives force from the first head and the second head. When the motor housing is substantially an “L” shape and the angle α is about a 90 degree angle, the first head applies pressure in a generally horizontal direction and the second head applies pressure in direction that varies 90 degrees from the direction of the first head. 
     The first motor is a first bi-directional motor and the second motor is a second bi-directional motor. The forward movement is stopped of the first bi-directional motor and the second bi-directional motor, the first shaft, second shaft, first contact surface, and second contact surface when a preset pressure is achieved upon the opposing object. The motor control switch in one variation is a foot-operated switch that allows the hands to remain free. 
     The invention is described in greater detail and specificity in the appended drawings, claims and description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the motorized clamp device with a single motor. 
     FIG. 2 is a side view of the motorized clamp device. 
     FIG. 3 shows a side view of the motorized clamp device in the configuration of a spreader device. 
     FIG. 4 shows a view of the channel, motor and motor collar with ears. 
     FIG. 5 is a top view of the motorized clamp device with two motors arranged at a 90 degree angle that is useful for picture frame assembly. 
     FIG. 6 a  is a perspective view of a foot switch for motor control. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Referring to FIGS. 1-6 a , specifically to FIG.  1  and FIG. 2, the motorized clamp device  10  includes a motor housing  12  having a first channel  14 . A first motor  16  is movably positioned within the first channel  14 . The motor control switch  18  and a reversing motor control switch  19  actuate the first motor  16  and are attached to the motor housing  12 . Attached to and powered by the first motor  16  is the first head  20 . The first head  20  has a first shaft  22  and a first contact surface  24 . There is a second contact surface  26  attached to the motor housing  12 . 
     The first motor  16  moves back and forth within the first channel  14  thereby increasing or decreasing the distance ‘d2’ between first contact surface  24  and a second contact surface  26 . This action clamps an object between the first contact surface  24  and a second contact surface  26 . The motorized capability of the motorized clamp device  10  minimizes the manual adjustments that must be performed by the operator. 
     The first torque collar  30  is attached to the motor housing  12 . The first torque collar  30  has a first aperture  32  that receives the first shaft  22 . When the first motor  16  causes the first shaft  22  to rotate, the first shaft  22  passes through the first aperture  32  of the first torque collar  30  and force is applied to an object by the first contact surface  24  and the second contact  26  surface. The first motor  16  travels within the first channel  14  as the first shaft  22  passes through the first torque collar  30 . 
     FIG. 4 shows a first motor collar  34  with a first ear  36  that prevents the first motor  16  from twisting within the first channel  14  when the first motor  16  rotates. The first motor collar  16  is secured around the perimeter and attached to the first motor  16 . The first ear  36  is shaped to fit within a groove  38  in the first channel  14 , so that the first channel  14  receives the first ear  36 . 
     When the first shaft  22  rotates, the first ear  36  is held within the first channel  14  thus preventing the first motor  16  from rotating within the motor housing  12 . Since the first motor  16  will not rotate this causes the first shaft  22  to move through the first torque collar  30  and the first motor  16  to move along with the first shaft  22 . The first motor  16  moves back and forth within the first channel  14  of the motor housing  12 . 
     When a larger object needs to be clamped a preferred embodiment includes a manual clamping bar  40  that can be adjusted. The manual clamping bar  40  has an inner surface  42 , an outer surface  43 , saw tooth edge  44 , with the saw tooth edge  44  having a plurality of teeth  46 . The second contact surface  26  is attached to the inner surface  42  of the manual clamping bar  40  and the motor housing  12  receives the manual clamping bar  40 . The manual clamping bar  40  can be incrementally adjusted along the plurality of teeth  46  by an adjustment device  48  that controls the range of adjustment of the manual clamping bar  40 . A travel stop  50  can prevent the manual clamping bar  40  from slipping out of the motor housing  12 . 
     After the operator adjusts the manual clamping bar  40  to the proper size and the object is placed between the first contact surface  24  and the second contact surface  26 , then the first motor  16  can be actuated to further tighten the motorized clamp device  10 . The object is then firmly secured between the second contact surface  26  on the manual clamping bar  40  and the first contact surface  24  of the first head  20 , when the first head  20  is actuated and applies pressure to a portion of the object. 
     The first motor  16  can be a first bi-directional motor  52 . When a second motor  70  is added the second motor  70  can be a second bi-directional motor  56 . Although not shown the first head  20  can include a ball joint so that the first head  20  can be adjusted to differing angles. 
     The motorized clamp device  10  has a power source  58  attached to the motor housing  12  for energizing the first bi-directional motor  52  or the second bi-directional motor  56 . The power source is typically a battery  60  that can be recharged or replaced. In a variation the power source  58  could be external and separate from the motorized clamp device  10 . Although not shown, an option to power the motorized clamp device  10  from a car cigarette lighter will provide ease and convenience for the operator when he is on remote construction sites without convenient access to electrical outlets. 
     The manual clamping bar  40  has a travel stop  50  that prevents the manual clamping bar  40  from inadvertently coming completely out of the motor housing  12 . When the travel stop  50  comes into contact with the motor housing  12  the travel stop limits the maximum distance of travel for the manual clamping bar  40 . The travel stop  50  can be a knurled knob  62  that is easy to grasp and can be threaded for easy removal from the manual clamping bar  40 . 
     One version of the manual clamping bar  40  has a range of adjustment of about 9 inches travel and the first head  20  has a range of adjustment of about 1 inch travel. 
     Referring particularly to FIG. 3, the manual clamping bar  40  has an outer surface  43  that can include a third contact surface  64  attached to the outer surface  43 . With the travel stop  50  removed the manual clamping bar  40  and motor housing  12  can be separated allowing the motor housing  12  to be reversed and then reattached to the manual clamping bar  40 . When the motor housing  12  is reversed the first shaft  22  and first contact surface  24  now face in the opposite direction. The first contact surface  24  faces about 180 degrees from the initial orientation of the first contact surface  24  such that the first contact surface  24  faces away from the third contact surface  64 . When the first shaft  22  passes through the first torque collar  30  and exits the motor housing  12  the first contact surface  24  and the third contact surface  64  increase the distance ‘d2’  66  between them, thereby creating a spreading effect. 
     The second contact surface  26  is attached to the inner surface  42  of the manual clamping bar  40 . When the motor housing  12  is in its initial position the object may be firmly secured between the second contact surface  26  on the manual clamping bar  40  and the first contact surface  24  of the first head  20 . The combination of a second contact surface  26  and a third contact surface  64  allows the manual clamp device  10  to be use both for clamping of objects and spreading of objects. 
     The motorized clamp device  10  can include the feature where the first bi-directional motor  52  or the second bi-directional motor  56  halts their forward movement of the first shaft  22  or second shaft  72  when a preset pressure is achieved upon the object. 
     Referring to FIG. 5, a second motor  70  may be added to the device  10  this requires there also be a second channel  74 . The second motor  70  is similar in structure to the first motor  16 . The second motor  70  is movably positioned within the second channel  74 . The second head  76  is attached to and powered by the second motor  70 . The second head  76  has a second shaft  72  and the second contact surface  26  is attached to the second shaft  72 . A second torque collar  78  is attached to the motor housing  12  with the second torque collar  78  having a second aperture  80  that receives the second shaft  72 . 
     A second motor collar  82  is attached to the second motor  70 . The second motor collar  82  has a second ear  84  that is received by the second channel  74 . When the second shaft  72  rotates the second ear  84  is held within the second channel  74  thus preventing the second motor  70  from rotating within the motor housing  12 . Since the second motor  70  is prevented from rotating this causes the second shaft  72  to move through the second torque collar  78  and the second motor  70  to move with the second shaft  72 . The second motor  70  moving back and forth within the second channel  74  of the motor housing  12 . 
     The first motor  16  and second motor  70  can be positioned within the motor housing  12  so that the first head  20  applies pressure in a generally horizontal direction  86  and a second head  76  applies pressure at a 90 degree angle to the first head  20 . 
     This arrangement of a first motor  16  and second motor  70  is ideal for use in picture framing applications where the sides  90 ,  90 ′ of the picture frame  92  must be assembled together by gluing. The first head  20  applies pressure to one side  90  of the picture frame and the second head  76  applies pressure to the other side  90 ,of the picture frame while the glue dries and adheres the sides  90 ,  90 ′ of the picture frame  92  together. Although not illustrated, when two motorized clamp device  10  are used then all four sides  90 ,  90 ′ of the picture frame  92  can be assembled and glued simultaneously. 
     FIG. 5 illustrates the first shaft  22  with a first axis  96  running along the first centerline  98  of the first shaft  22  and a second axis  100  running along the second centerline  102  of the second shaft  72 . The intersection of the first axis  96  and second axis  100  create an angle α  104  that is less than a 180 degree angle, such that an opposing object receives force from the first head  20  and the second head  76 . 
     The first motor  16  and second motor  70  can be positioned in substantially an “L” shape. One alternate arrangement for picture framing applications is with the motor housing  12  in substantially an “L” shape with both the first motor  16  and second motor  70  contained within the motor housing  12 . The angle α  104  is about a 90 degree angle so that the first head  20  applies pressure in a generally horizontal direction  86  and the second head  76  applies pressure at a 90 degree angle to the first head  20 . Pressure can then be applied in two directions to the two sides  90 ,  90 ′ of the picture frame  92  that are being adhered together. 
     FIG. 6 a  shows another variation of a motor control switch  18  that is a foot-operated switch  106 . This version is specifically design for the picture framing applications with two motors  16 ,  70 . There is a left side  108  that controls the first shaft  22  and a right side  110  that controls the second shaft  72 . The left side  108  has an “in” button  112  for retracting the first shaft  22  back into the motor housing  12  and an “out” button  114  for moving the first shaft  22  toward the object to be clamped. Similarly, the right side  110  has an “in” button  116  for retracting the second shaft  72  and an “out” button  118  for moving the second shaft  72  toward the object to be clamped. 
     Although the present invention has been described in considerable detail with regard to the preferred versions thereof, other versions are possible. Therefore, the appended claims should not be limited to the descriptions of the preferred versions contained herein.