Abstract:
The present invention is a long reach press comprising a low force actuator for operably urging first tooling into a working position. It further includes an opposed high force actuator for operably urging second tooling into engagement with the first tooling. The low force actuator includes a positive stop actuator including a slide block stop for operatively supporting and restraining movement of the first tooling when engaged with the second tooling. The slide block is moveable between a stop extended position and a stop retracted position.

Description:
[0001]     The present application claims priority from previously filed Provisional Application 60/586,223 filed Jul. 9, 2004 as well as U.S. Provisional 60/561,527 filed Apr. 13, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to presses and in particular relates to pneumatic hydraulic and air operated long reach presses.  
       BACKGROUND OF THE INVENTION  
       [0003]     Presses are used for stamping, punching, clinching, nut insertion, shearing and other functions on metals and other materials. Presses generally are designed to impart forces onto working materials and these forces are generated through mechanical, hydraulic, pneumatic or air actuated devices. Specialized presses have been developed for working with parts that have particularly deep sections, such as channel letters. Channel letter for example have a back plate which is clinched to a side wall producing a deep and wide U- channel which is then used for production of letters of various shapes. These channel letters can exceed 10 inches in depth and in order to fasten the back plate to the side wall, the press must have sufficient reach in order to penetrate this depth so that the pressing operation which in this particular case is clinching can be carried out.  
         [0004]     Typically in order to carry out the clinching process, the two parts to be clinched together must be sandwiched between male and female tooling components, wherein these tooling components are brought into contact with the parts to be assembled via the press. Therefore, when one wishes to clinch together two parts having a large depth profile, such as channel letters, the difficulty that one faces is presenting the parts in between the male and female tooling components. Currently the practise is to have a long upright standing fixed lower tooling which is long enough to penetrate the entire depth of the channel letter. The upper tooling is attached to an upper hydraulic cylinder having a very long stroke capability such that when the upper hydraulic cylinder is in the retracted position, the operator can manoeuvre the channel letter onto the lower fixed tooling. This set up requires the use of expensive long stroke hydraulic cylinders with the associated safety issues that arise when the upper tooling approaches the part in order to carry out clinching and/or other pressing operations.  
         [0005]     It would be desirable to be able to provide for a long reach press which eliminates the safety issues and the expense of the requirement of having a long reach hydraulic type cylinder in order to achieve the long strokes required for parts having large depth profiles.  
       SUMMARY OF THE INVENTION  
       [0006]     Long reach press comprising: 
        (a) a high force actuator connected at one end to upper tooling  110  having the capability of moving upper tooling under high forces:     (b) lower tooling adapted to cooperate and make contact with upper tooling and a low force means for moving lower tooling between a lower tooling lowered position and a lower tooling raised position, such that when lower tooling is in the raised position the upper and lower tooling will make contact upon actuation of the high force actuator.        
 
         [0009]     Wherein the low force means includes a low force actuator, capable of moving lower tooling between a lower tooling lowered position and a lower tooling raised position.  
         [0010]     Wherein said low force means further including a positive stop actuator which includes a slide block stop, wherein said slide block stop can be extended between a stop extended position and a stop retracted position, wherein the stop extended position and the tooling in the lower tooling raised position, the lower tooling is prevented from moving downwardly against the slide block stop.  
         [0011]     The present invention a long reach press includes: 
        1) a low force actuator for operably urging first tooling into a working position; 
            (b) an opposed high force actuator for operably urging second tooling into engagement with the first tooling;     (c) wherein said low force actuator including a positive stop means for restraining movement of the first tooling when in engagement with the second tooling.    
               
 
         [0015]     Preferably wherein said stop means including a positive stop actuator including a slide block stop for operatively supporting and restraining movement of the first tooling when engaged with the second tooling.  
         [0016]     Preferably wherein said slide block moveable between a stop extended position and a stop retracted position.  
         [0017]     Preferably wherein said first tooling being lower tooling positioned below and vertically opposed to second tooling being upper tooling positioned vertically above lower tooling.  
         [0018]     The present invention a long reach press includes: 
        (a) a low force actuator for operably urging lower tooling into a raised position;     (b) a vertically opposed high force actuator for operably urging upper tooling into engagement with the lower tooling;     (c) the press further including a positive stop means for restraining movement of the lower tooling when in a raised position and in engagement with the upper tooling.        
 
         [0022]     Preferably, wherein the stop means including a positive stop actuator including a slide block stop for operatively supporting and restraining movement of the lower tooling when engaged with the upper tooling.  
         [0023]     Preferably, wherein the slide block moveable between a stop extended position and a stop retracted position.  
         [0024]     Preferably, wherein the positive stop actuator including a position sensor for monitoring the position of the slide block stop as it moves between the stop extended position and the stop retracted position.  
         [0025]     Preferably, wherein the slide block stop slideably received with a lower tooling housing.  
         [0026]     Preferably, wherein the low force actuator moveable between a lowered position and a raised position when the slide block stop in the stop retracted position thereby defining a lower stroke.  
         [0027]     Preferably, wherein the lower tooling moving along a vertical direction and the slide block stop moving along a lateral direction perpendicular to the vertical direction.  
         [0028]     Preferably, wherein the high force actuator including a WAMP unit capable of moving the upper tooling along an upper stroke and into engagement at high force with the lower tooling.  
         [0029]     Preferably, wherein the lower tooling when in the lowered position is retracted below a working table such that the work piece can be easily slid over top of the lower tooling.  
         [0030]     Preferably, wherein said slide block stop being U shaped for operably engaging with a lower tooling stop surface.  
         [0031]     The present invention a method of operating a press includes: 
        (a) placing a work piece on a working table; wherein mounted below the working table a low force actuator including lower tooling; and mounted above the working table a vertically opposed high force actuator including upper tooling;     (b) urging under low force, lower tooling from below the table into a raised position thereby engaging and supporting said work piece;     (c) a means for restraining movement of the lower tooling when in a raised position.     (d) urging under high force upper tooling into engagement with the work piece and lower tooling;        
 
         [0036]     Preferably wherein said restraining means including a positive stop means for restraining movement of the lower tooling when in the raised position and in engagement with the upper tooling.  
         [0037]     Preferably wherein the stop means including a positive stop actuator including a slide block stop for operatively supporting and restraining movement of the lower tooling when engaged with the upper tooling.  
         [0038]     The present invention a long reach press includes: 
        (a) a high force actuator including at one end upper tooling, wherein the actuator operable for moving upper tooling under high forces;     (b) a low force actuator for operable urging lower tooling between a lowered position and a raised position, such that when lower tooling is in the raised position the upper and lower tooling will make contact upon actuation of the high force actuator.        
 
         [0041]     Preferably, wherein said low force means further including a positive stop actuator which includes a slide block stop, wherein said slide block stop can be extended between a stop extended position and a stop retracted position, wherein the slide block stop in the stop extended position and the lower tooling in the raised position, the lower tooling is prevented from moving downwardly past the slide block stop.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0042]     The invention will now be described by way of example only with reference to the following drawings in which:  
         [0043]      FIG. 1  is a schematic representation of a conventional currently used prior art press.  
         [0044]      FIG. 2  is a schematic representation of the present invention, a long reach press with the stop in the extended position.  
         [0045]      FIG. 3  is a schematic representation of the present invention a long reach press with the stop in the retracted position.  
         [0046]      FIG. 4  is a front schematic perspective view of the present invention, a long reach press mounted onto a frame.  
         [0047]      FIG. 5  is a front schematic perspective view of the present invention, a long reach press mounted onto a frame with the table and guards removed showing the high force actuator and the low force actuator.  
         [0048]      FIG. 6  is a schematic cross sectional view of the low force actuator together with the positive stop actuator.  
         [0049]      FIG. 7  is a schematic top perspective view of the low force actuator together with the positive stop actuator with the lower tooling in the raised position, and the stop in the extended position.  
         [0050]      FIG. 8  is a schematic top perspective view of the low force actuator together with the positive stop actuator with the lower tooling in the lower position. The stop on the retracted position showing details of the slide block stop.  
         [0051]      FIG. 9  is a schematic cross sectional view of a WAMP actuator showing the internal details.  
         [0052]      FIG. 10  is a schematic top perspective view of the components of a channel letter.  
         [0053]      FIG. 11  is a schematic perspective view of a channel letter being placed on the working table showing the lower tooling in the raised position extended inside the formed sides of the channel letter.  
         [0054]      FIG. 12  is a front schematic perspective view of the present invention a long reach press mounted onto a frame together with a channel letter showing the lower tooling in the raised position.  
         [0055]      FIG. 13  is a perspective side elevational view showing a channel letter in an insert removed position on a working table with the lower tooling in the lowered position.  
         [0056]      FIG. 14  is a schematic side elevational view showing a channel letter in a working position with the lower tooling in the raised position.  FIG. 15  is a side schematic perspective view of the present invention a long reach press together with a frame with a channel letter in the working position on the working table with the lower tooling in the raised position.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     DEFINITIONS  
       [0057]     “High Force”=Normally greater than 100 lb force 
        For clinching operations normally greater than 1000 lb force is used and typically closer to 5000 lbs force is employed.        
 
         [0059]     “Low Force”—Normally less than 100 lb force, and typically 30 lbs force is employed in order to avoid operator injury.  
         [0060]     Prior Art  
         [0061]     Referring first of all to  FIG. 1  which shows a prior art press shown generally as  900 . Prior art press  900  includes a high and low force actuator  902  comprised of a single hydraulic cylinder  904 , piston  906 , piston rod  908  having attached on one end thereof upper tooling  910 . In order to achieve the long reach required, high and low force actuator  902  moves through a long upper stroke  914  which is comprised of both a low force stroke portion  916  and a high force stroke portion  918  as depicted in  FIG. 1 . In other words, hydraulic cylinder  904  advances upper tooling  910  through a very long upper stroke  914  in two stages. Firstly it advances upper tooling  910  under low pressure or low force, along low force stroke  916  and then as upper tooling  910  approaches the work piece it applies high force, moving upper tooling  910  through high force stroke  918 . In order to achieve this type of controlled movement of hydraulic cylinder  904 , sophisticated and expensive controls must be applied to hydraulic cylinder  904  in order to carefully control the low and high force strokes. Upper stroke  914  may be of the order of six to 12 inches.  
         [0062]     Further, lower tooling  920  is fixed to a base  922  and work pieces must be placed over the top of lower tooling  920  for further operation. The disadvantages of prior art press  900  as shown in  FIG. 1  are the expensive dual stroke hydraulic cylinder  904  that is required along with the sophisticated control system necessary in order to move upper tooling  910  through the low force stroke portion  916  and as well as the high force stroke portion  918 . Secondly, there is the issue of safety, particularly of concern is injury to personnel using prior art press  900 . The large movement of upper tooling  910  through upper stroke  914  increases the likelihood that something or somebody could be caught and/or injured by the movement of upper tooling  910  unless the force of the upper tooling movement is in some manner controlled to eliminate the possibility of injury. Thirdly, it is very inconvenient and time consuming and labour intensive to move the work piece onto the fixed lower tooling  920  and generally speaking manual labour must be employed in order to lift parts, such as channel members manually over top of lower tooling  920  so that it can be presented to upper tooling  910 .  
         [0063]     Present Invention  
         [0064]     The present invention is a described and depicted in the remainder of the drawings in particularly referring to  FIGS. 2 through 6 , the present invention a long reach press is shown generally as  100  and includes the following major components, namely high force actuator  102 , low force actuator  202  and positive stop actuator  302 .  
         [0065]     High force actuator  102  includes piston  104 , cylinder  106 , piston rod  108 , having upper tooling  110  attached at one end thereof. Upper tooling  110  moves through a high force small upper stroke  114  as depicted in  FIG. 2 . Upper stroke  114  is usually of the order of ½″ to 1″. A person skilled in the art will note that high force actuator  102  maybe selected from various commercial units that are currently on the market. It may include a hydraulic cylinder, a pneumatic cylinder, an air diaphragm pneumatic actuator or any other types of high force actuator which will provide the necessary force and stroke for the application.  
         [0066]     Low force actuator  202  includes cylinder  204 , piston  206 , cylinder rod  208  and lower tooling  210  which is shown in lower tooling raised position  212  in  FIG. 2 . Lower tooling  210  is moved through lower stroke  220  under low force conditions. Lower stroke  212  is usually of the order of 3″ to 15″, or even more.  
         [0067]     Positive stop actuator  302  includes cylinder  304 , piston  306 , cylinder rod  308 , a position sensor  310  and a slide block stop  312 . Slide block stop  312  is shown in the stop extended position  314  and is moved laterally along lateral direction  316  as shown in  FIG. 2 .  
         [0068]     Lower tooling  210  is shown in the lower tooling lowered position  214  in  FIG. 3  and slide block stop  312  is shown in the stop retracted position  315  also in  FIG. 3 . Slide block stop  312  moves along lateral direction  316  between stop retracted position  315  and stop extended position  314 .  
         [0069]     Referring now to  FIG. 4 , showing the present invention the long reach press  100  installed in typical fashion in a C-frame  408  which includes an air reservoir  406 , a working table  404 , base  402 . The high force actuator preferably is a WAMP actuator  103  (WAMP=whiting air multiple press) which is a diaphragm type air multiple pneumatic press capable of moving upper tooling  110  through upper stroke  114  at the forces required.  
         [0070]     Referring now to  FIG. 5 , which shows the long reach press  100  mounted onto a C-frame  408 , wherein for greater clarity, working table  404  as well as some guarding has been removed. Lower tooling  210  is shown in lower tooling raised position  212  and low force actuator  202  further includes lower tooling housing  216  and cylinder mounting spacer  214 . Positive stop actuator  302  further includes positive stop housing  318  as depicted in  FIG. 5 .  
         [0071]     Referring now to  FIG. 6 , low force actuator  202  is depicted together with positive stop actuator  302  in cross sectional fashion with lower tooling  210  in the lowered tooling raised position  212  and the slide block stop  312  in stop retracted position  315 . With slide block stop  312  in retracted position  315 , lowering tooling  210  can be raised and lower by piston  206  sliding within cylinder  204 .  FIG. 6  further more clearly depicts cylinder mounting spacer  214  as well as guide sleeve  218  and lower tooling housing  216 .  
         [0072]     Referring now to  FIG. 7  and  8  for further clarification,  FIG. 7  is a top schematic perspective view of the low force actuator  202  together with the positive stop actuator  302  with lower tooling  210  in the lower tooling raised position  212  and slide block stop  312  in the stop extended position  314 . The drawings also show cylinder rod  208  together with stop position sensor  310  and lower tooling position sensor  280 .  
         [0073]      FIG. 8  is a top schematic perspective view of the low force actuator  202  together with the positive stop actuator  302  showing the lower tooling  210  in the lower tooling lowered position  214  together with slide block stop  312  in the stop retracted position  315  and as well showing a lower tooling stop surface  282  which makes contact with stop face  380  of slide block stop  312  when the lower tooling  210  is in the raised position  212 .  
         [0074]     Referring now to  FIG. 9  which is a schematic cross sectional view of WAMP actuator  103  wherein WAMP stands for WHITING AIR MULTIPLE PRESS, one will see that WAMP actuator  103  includes  3  chambers namely upper chamber  502 , intermediate chamber  504  and lower chamber  506  and within each chamber is housed a diagram  508  together with a plunger, namely upper plunger  510  in upper chamber  502 , intermediate plunger  512  in intermediate chamber  504  and lower plunger  514  in lower chamber  506 . Each chamber is defined by housing  507  and the housings are held together by frame  520  and rods  522 . Lower plunger  514  includes an output shaft  518  for transferring the force as desired. Return springs  516  returns the plungers  510 ,  512  and  514  and the diaphragms  508  after the power stroke has been completed. In addition, there is an adjusting nut  524  to adjust the upper range of the stroke. WAMP units typically use approximately 100 PSI of air which is inlet into each chamber individually, thereby multiplying the force that is available at output shaft  518 . Typically 3000 pounds of force are available per chamber for a total of 9000 pounds of force at the output shaft and typically the power stroke is approximately 1″ in length. WAMP actuator  103  is the unit which can be used in the high force actuator  102  portion of long reach press  100 , however other actuators are also possible. The advantage of the WAMP actuator  103  is the lower cost, the very high force, the low stroke and the large number of power strokes that can be obtained in the short period of time.  
         [0075]     Referring now to  FIG. 10, 11  and  12 ,  FIG. 10  schematically shows channel letter  600  which normally is comprised of formed sides  604  and a backing plate  602 . Long reach press  100  typically must clench together the backing plate  602  with the formed sides  604 . Channel letter  600  is a typical example of an application of long reach press  100  where a very long penetration of the tooling is required in order to access the area where the actual work must be completed.  FIG. 11  for example shows channel letter  600  mounted onto a working table  404  with lower tooling  210  in the raised position  212 , wherein upper tooling  110  and lower tooling  210  are just coming into contact.  FIG. 12  shows the same features as  FIG. 11 , however with long reach press mounted into a C-frame  408 .  
         [0076]      FIG. 13  shows schematically a channel letter  600  mounted onto a working table  404  with lower tooling  210  in the lowered position  214  such that when lower tooling  210  is in the lower tooling lowered position  214 , one can easily slide channel letter  600  across working table  404  and therefore, in this position long reach press  100  is in the insert remove position  620  as schematically shown in  FIG. 13 . When channel letter  600  is placed in the desired position, lower tooling  210  is raised to the lower tooling raised position  212  which normally is concealed to the eye since the tooling is raised inside the formed sides  604  of channel letter  600  and therefore, normally unseen. Once lower tooling  210  is raised to the lower tooling raised position  212  as shown in  FIG. 14 , channel letter  600  is in a working position  622  as shown in  FIG. 14  and now the clinching operation between upper and lower tooling using the high force actuator  102  can be activated.  FIG. 15  shows the same features as  FIG. 14 , however with the long reach press  100  mounted into a C-frame  408 .  
         [0077]     In Use  
         [0078]     Referring now to  FIG. 2, 3  and  4 , a work piece (not shown) such as a channel number is placed on working table  404  and can be placed in position between upper and lower tooling  110  and  210 , by lowering lower tooling  210  to lower position  214  such that the work piece can be slid over lower tooling  210 . Lower tooling  210  in  FIG. 4  is shown in the lower tooling raised position  212 , with lower tooling  210  projecting vertically upward in vertical direction  190  from working table  404 . When lower tooling  210  is in the lower tooling lowered position  214 , lower tooling  210  is below or flush with working table  404 , thereby allowing easy movement of parts across working table  404 .  
         [0079]     Therefore, as schematically shown in  FIG. 3  with lower tooling  210  in lower tooling lowered position  214  a work piece can be placed over lower tooling  210 . Once the work piece is in place, lower tooling  210  is raised to the lower tooling raised position  212  (also referred to as the working position) as shown in FIGS.  4  and also in  FIG. 2 , so that subsequent pressing operations can occur between upper tooling  110  and lower tooling  210 . Lower tooling  210  can be moved between lower tooling raised position  212  and lower position  214  when slide block stop  312  is in the stop retracted position  315  as shown in  FIG. 3 . Once the work piece has been put in place over lower tooling  210  and lower tooling  210  is raised to the lower tooling raised position  212 , positive stop actuator  302  is engaged by laterally sliding slide block stop  312  from the stop retracted position  315  to the stop extended position  314 . Slide block stop  312  positively engages with the bottom of lower tooling  210 , such that there is a positive mechanical stop preventing lower tooling  210  from moving downwardly in vertical direction  190 . Therefore, a large amount of force can be placed onto lower tooling  210  by high force actuator  102  since lower tooling  210  is rigidly supported by slide block stop  312 .  
         [0080]     With slide block stop  312  in the stop extended position  314  and lower tooling  210  in the lower tooling raised position  212 , high force actuator  102  can now be actuated through upper stroke  114  at high forces. In this manner, parts with very deep profiles such as channel letters can easily be moved across working table  404  to a working position just below upper tooling  110  and clinching, pressing, shearing, stamping and other operations can be carried out by long reach press  100 .  
         [0081]     A person skilled in the art will see the advantageous of having the ability to raise and lower, lower tooling  210  from below working table top  404 . First of all there is ease of movement of parts across table top  404  in that with lower tooling  210  in the lower position  214 , parts can easily slide across working table  404  without running into lower tooling  210 . With the prior art press  900 , the work piece would have to be manually raised above the fixed lower tooling  920  in order to be placed into a working position.  
         [0082]     Secondly, lower stroke  220  occurs from below and inside a deep contoured part, thereby eliminating a safety issue, namely that an operator would no longer be exposed to the long stroke movement as in prior art press  900 . A person skilled in the art will recognize that this lower pressure long stroke approach of lower tooling  210  can range anywhere from 3 to 15 inches and/or more and therefore, creates a major safety concern in regard to operators being exposed to the movement of lower tooling  210 . In the present long reach press  100 , the operator is shielded by the actual work piece as lower tooling  210  is raised to the lower tooling raised position  212  within the work piece itself. In the present long reach press  100 , not only is the operator shielded by the actual work piece as lower tooling  210  is raised to the lower tooling raised position  212  within the work piece itself, but in addition the operating force of the lower tooling is low enough that operator injury is minimized and normally eliminated.  
         [0083]     Furthermore, since high force actuator  102  no longer needs to be moved through both low force stroke  916  as well as a high force stroke  918 , more economical high forced actuators  102  can be utilized such as pneumatic units which are ideally suited to providing high force, low stroke actuations at relatively less expense. The prior art long low force stroke  916  shown in prior art press  900  is completely eliminated in that the high force actuator  102  of long reach press  100  only needs to move through the short (½ to 1″) upper stroke  114 . This also eliminates the controls and the further instrumentation and mechanical arrangements necessary in order to control the movement of the prior art high and low force actuator  902  through both the low force stroke  916  and the high force stroke  918 .  
         [0084]     Furthermore, the control systems required for the long reach press  100  are greatly simplified in that with the prior art unit, high and low force actuator  902  had to be controlled through a high and low pressure operation which generally requires pre-loaded springs and position sensors and its associated electronic and electrical controls. In long reach press  100 , the high and low pressure strokes are separated, in that the low pressure long stroke is achieved from below the table, namely with a separate lower force actuator  202 .  
         [0085]     Since high force actuator  102  only needs to move through a shorter upper stroke  114 , hydraulic cylinders can be eliminated in their entirety and less expensive pneumatic units can be used instead of hydraulic cylinders for high force actuator  102  as well as low force actuator  202  and positive stop actuator  302 .  
         [0086]     Finally, the long reach press  100  operates much more quickly than the prior art press  900  since the high force actuator  102  which can be a pneumatic unit can cycle much quicker than the hydraulic prior art actuator  902 .  
         [0087]     Furthermore, a person skilled in the art will note that there is a significant machine size reduction, in that the overall height of the entire long reach press can be lowered since the approach of lower tooling  210  occurs from below, rather than as previously from above. Long reach press  100  utilizes the existing distance between working table  404  and the floor for providing for the low pressure low force approach of lower tooling  210  from the lower tooling lowered position  214  to the lower tooling raised position  212 . Therefore, the overall height of long reach press can be lowered essentially by the distance of the low force stroke  916  as shown in  FIG. 1  or the distance of the lower stroke  220  as shown in  FIG. 2 . Therefore, the entire height of the machine can be reduced with its associated cost and space savings.  
         [0088]     Persons skilled in the art will recognize that the press may be arranged horizontally rather than vertically in which case a first tooling equivalent to lower tooling  210  and a second tooling equivalent to upper tooling  110  could be horizontally opposed or in other configurations.  
         [0089]     It should be apparent to persons skilled in the arts that various modifications and adaptation of this structure described above are possible without departure from the spirit of the invention the scope of which defined in the appended claim.