Patent Publication Number: US-6981432-B2

Title: Hose clamp tool

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation of U.S. application Ser. No. 10/604,955 filed Aug. 28, 2003. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an apparatus for installing a hose clamp and a method for installing a hose assembly with the apparatus. 
   2. Background Art 
   Hoses are used to make connections between components of fluid systems. For example, hoses are used to connect vehicle coolant system components, such as a radiator or heater core, to an internal combustion engine. These hoses are made of rubber, polymeric elastomers, or another flexible material. Connections are made by installing the hose over a pipe or mating member that extends from a fluid system component. 
   A hose clamp is used to hold the hose firmly against the mating member to provide a fluid tight seal between the hose and the mating member. A hose clamp is a circular spring steel wire or band with radially extending tabs at each end of the wire. A hose clamp is set in a pre-expanded position and glued to the outer surface of a hose to facilitate installation. One type of pre-expanded hose clamp is the “clipless” type that incorporates a latching member for holding the clamp in an open position without a separate retaining clip. 
   Hose connections are often made in locations that are difficult to access, such as at an engine block water jacket point near the bottom of an engine block. Such locations are frequently difficult to see and inspect. If a clamp is not properly engaged, a watertight seal is not formed between the hose and the mating member. In the case of a coolant system, improper clamping can result in coolant leaks, engine overheating, warpage of the head of an engine block, and engine failure necessitating expensive repairs or engine replacement. 
   In the prior art, pliers were used to grasp and squeeze together the hose clamp tabs to disengage the latching member and permit the clamp to move from an open position to a clamped position. Such tools did not include a feedback mechanism to confirm that the clamp had in fact moved to the clamped position securing the hose. In addition, these tools typically could not be adjusted or rotated to facilitate access to hard-to-reach clamps and could not be adapted to left-handed or right-handed user preferences. 
   Recent efforts to develop a tool that incorporated a feedback mechanism, such as that in U.S. provisional patent application Ser. No. 60/417,894, unsuccessfully attempted to utilize a single rod design to release the clamp and provide feedback. This experimental tool included a single rod with a hook formed at one end. The hook is inserted into a clamp tab and when the user pulls on a lever, the hooked rod pulls on a spring and on the clamp tab. If sufficient force is applied, the latching member is disengaged, permitting the clamp to move from an open position to a closed position. Disengagement of the latching member also releases tension on the spring, causing the hooked rod to recoil or kickback past its initial position and actuate a sensor, thereby signaling closing of the clamp. These “inertia operated switch” tools released clamps inconsistently and did not provide reliable feedback that the clamp had closed. In addition, these tools did not accommodate ergonomic adjustments, such as rotating the position of the hook for easy engagement of the clamp. 
   Before the Applicants&#39; invention there was a need for an apparatus to install hose clamps and to provide positive feedback indicating that the hose clamp had engaged the hose. Problems associated with the prior art as noted above and other problems are addressed by Applicants&#39; invention as summarized below. 
   SUMMARY OF THE INVENTION 
   According to one aspect of the present invention, a hose clamp installation tool is provided that includes a hook for engaging a clamp and a rod located adjacent to the hook that releases the clamp. A sensor detects whether the clamp has shifted to a closed position. The sensor may be a proximity switch or a load cell. 
   The installation tool can be pneumatically or manually actuated. If the tool is pneumatically actuated a piston may be attached to the rod. Pressure applied to the piston drives the rod from an initial position into engagement with the clamp. A spring may also be provided that biases the rod to return it to an initial position. Alternately, an air cylinder may be coupled to the rod. 
   A trigger may be moved by the clamp when the clamp shifts from an open position to a closed position. A feedback rod may be located adjacent to the trigger. The feedback rod moves in response to the movement of the trigger when the clamp shifts from the open position to the closed position. One or more sensors can be used to detect movement of the feedback rod and indicate that the clamp has shifted to a closed position. A first sensor can be used to detect changes in the position of the rod and a second sensor can be used to detect changes in the position of the feedback rod. 
   A spool may be disposed around the rod and biased to a start position by a spool spring. The spool may be contacted by the feedback rod and moved from the start position when the feedback rod is actuated by the trigger. A sensor, such as proximity switch, can be mounted to detect movement of the spool and indicate the clamp has shifted to a closed position. 
   According to other aspects of the invention relating to the housing, the hook used to engage the clamp can be attached to a tubular housing. The tubular housing may also partially enclose the rod. 
   The tubular housing may be selectively connected to a handle in different positions to permit the hook to be positioned in a convenient orientation relative to the handle. 
   According to another aspect of the invention, a method for installing a hose assembly with the hose clamp installation tool is provided. The method begins by inserting the hook into an aperture of the clamp. A rod is advanced to disengage the clamp from an open position. A trigger is moved in response to disengaging the clamp. Movement of the trigger shifts the feedback rod. A sensor monitors the position of the feedback rod to indicate that the clamp has shifted to the closed position. 
   According to a final aspect of the invention, an acceptable hose assembly signal is generated when the time between sensing a change in the rod position and sensing the shifting of the feedback rod corresponds to an accepted time value. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a hose clamp installation tool and a hose assembly before installation. 
       FIG. 2  is a perspective view of a hose clamp installation tool. 
       FIG. 3  is a section view of a pneumatic hose clamp installation tool with the unclamp rod in an initial position and the feedback rod in a start position. 
       FIG. 4  is a section view of a pneumatic hose clamp installation tool with the unclamp rod in an actuated position and the feedback rod in a partially shifted position. 
       FIG. 5  is a section view of a pneumatic hose clamp installation tool with the unclamp rod in an actuated position and with the feedback rod shifted. 
       FIG. 6  is a section view of a manual hose clamp installation tool. 
       FIG. 7  is a section view of a second embodiment of a pneumatic hose clamp installation tool. 
       FIG. 8  is a section view of a second embodiment of a manual hose clamp installation tool. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
   Referring to  FIG. 1 , an engine  10  and a hose assembly  12  are shown. The engine  10  includes a flange  14  that mates with the hose assembly  12 . The hose assembly  12  includes a hose  16  and a clamp  18 . The clamp  18  can be attached to the hose  16  with an adhesive. The clamp  18  is shown in an open position to facilitate sliding the hose  16  over the flange  14 . The clamp  18  includes a first tab  20  and an aperture tab  22 . The aperture tab  22  includes an aperture  24 . A latch  26  engages the aperture tab  22  to hold the clamp  18  in an open position. 
   An installation tool  28  is also shown that includes a hook  30  that is received in the aperture  24  to allow the installation tool  28  to latch onto the clamp  18 . 
   Referring to  FIG. 2 , the end of the installation tool  28  that engages the clamp  18  is shown more clearly. The installation tool  28  includes a housing  32 . The housing  32  includes a handle  34  for grasping the installation tool  28 . A switch  36  is located adjacent to the handle  34  that activates the installation tool  28  when engaged. A tubular housing  38  is rotatably attached to the housing  32 . The hook  30  is attached to a distal end of the tubular housing  38 . The tubular housing  38  at least partially encloses an unclamp rod  42  and a trigger  44 . 
   Referring to  FIG. 3 , the installation tool  28  is shown with the hook  30  engaging a clamp  18  that is latched in an open position. The unclamp rod  42  is located adjacent to the first tab  20  of the clamp  18 . A piston  52  is attached to an end of the unclamp rod  42 . The unclamp rod  42  passes through a spool  54 . A collar  56  is attached to the unclamp rod  42  between the spool  54  and the piston  52 . The unclamp rod  42  passes through an unclamp spring  58  located between the piston  52  and a cylinder  60 . The unclamp spring  58  biases the unclamp rod  42  to an initial position as shown. When the unclamp rod  42  is in the initial position, collar  56  is adjacent to a first sensor  62  that detects the position of the unclamp rod  42 . The unclamp rod  42  also passes through a spool spring  64  located between the collar  56  and the spool  54 . The spool spring  64  biases the spool  54  to a start position adjacent to a rotatable housing  66 . When the spool  54  is in the start position, a spool collar  68  is not adjacent to a second sensor  74 . 
   Referring to  FIG. 4 , the installation tool  28  includes a port  69  that is connected to a source of pressurized air. When the switch  36  is engaged, pressurized air enters the cylinder  60  and applies a force against the piston  52 , causing the unclamp rod  42  to engage the first tab  20  of the clamp  18 . As the unclamp rod  42  engages the first tab  20 , the unclamp spring  58  is compressed and the collar  56  moves away from the first sensor  62 . At the same time, the spool spring  64  is partially compressed between the collar  56  and the spool  54 . When sufficiently advanced in the direction indicated by the arrow on the unclamp rod  42 , the unclamp rod  42  releases the latch  26  and the clamp  18  is permitted to shift from an open position to a closed position as indicated. 
   Referring to  FIG. 5 , as the clamp  18  snaps to the closed position, the first tab  20  momentarily contacts the trigger  44 . The trigger  44  then rotates about a pivot pin  70 . As the trigger  44  rotates, it contacts a feedback rod  72 . The feedback rod  72  advances and contacts the spool  54 . The spool  54  moves away from the rotatable housing  66  and compresses the spool spring  64 . The movement of the spool  54  causes the spool collar  68  to be shifted to a position adjacent to the second sensor  74 , thereby providing feedback that the latch  26  has released and that the clamp  18  has shifted to the closed position. When the first tab  20  no longer contacts the trigger  44 , the spool spring  64  biases the spool  54 , feedback rod  72 , and trigger  44  back to their respective start positions as shown in  FIG. 3 . The flow of pressurized air against the piston  52  is stopped when the switch  36  is released and the unclamp spring  58  exerts a biasing force on the unclamp rod  42 , returning it to the initial position. 
   Also shown in  FIG. 5 , a bearing  76  is located between the housing  32  and the rotatable housing  66 . The bearing  76  permits the rotatable housing  66  to rotate with respect to the housing  32 . The tubular housing  38  is attached to and rotates with the rotatable housing  66 . As a result, the hook  30  attached to the tubular housing  38  can be moved to a variety of positions relative to the housing  32 . 
   Referring to  FIG. 6 , a manual installation tool  80  is shown. This embodiment includes a handle grip  82 . Handle grip  82  protrudes through a housing  84  and is held rotatably in place with a pin  86 . The handle grip  82  includes a first surface  88  adjacent to a rod end  90  and a second surface  92  adjacent to a spool surface  94 . When the handle grip  82  is engaged, the first surface  88  contacts the rod end  90  causing an unclamp rod  96  to engage the first tab  20  of the clamp  18 . When the unclamp rod  96  engages the clamp  18 , a narrow region  98  of the unclamp rod  96  is moved adjacent to a first switch  100 , which detects the position of the unclamp rod  96 . Also, the second surface  92  moves away from the spool surface  94 . 
   As the clamp  18  snaps to the closed position, the first tab  20  momentarily contacts a trigger  102 . The trigger  102  then rotates about a pivot pin  104 . As the trigger  102  rotates, it contacts a feedback rod  106 . The feedback rod  106  advances and contacts a spool  108 . The spool  108  moves away from a rotatable housing  110 . The movement of the spool  108  repositions a spool collar  112  adjacent to a second sensor  114 , thereby providing feedback that the latch  26  has released and that the clamp  18  has shifted to a clamped position. When the handle grip  82  is released, the second surface  92  contacts the spool surface  94  and returns the spool  108 , feedback rod  106 , and trigger  102  to their respective start positions. Likewise, an unclamp spring  116  biases the unclamp rod  96  to return to its initial position. 
   Alternatively, the second sensor or sensor  74 ,  114  can be positioned to detect movement of the feedback rod  72 ,  106 , thereby eliminating the need for the spool  54 ,  108 . The second sensor  74 ,  114  could also be positioned to detect movement of the trigger  44 ,  102 , thereby eliminating the need for the spool  54 ,  108  and the feedback rod  72 ,  106 . 
   A successful installation signal may be generated only if the clamp  18  shifts from an open position to a closed position within a predetermined amount of time. An elapsed time is measured between sensing the shifting of the unclamp rod  42 ,  96  with first sensor  62 ,  100  and sensing the actuation of the trigger  44 ,  102  or feedback rod  72 ,  106  or spool  54 ,  108  with the second sensor  74 ,  114 . If the elapsed time is within a predetermined time interval, a successful installation signal is generated. The successful installation signal can be used as an input to activate an indicator, such as a light or buzzer, increment a counter, or register the information in a database verifying that the clamp has been closed. Failure to obtain a successful installation signal could be used to halt a vehicle assembly line. 
   Referring to  FIG. 7 , another embodiment of a pneumatic hose clamp installation tool is shown. The installation tool  120  is shown with a hook  122  engaging a clamp  18  that is latched in an open position. An unclamp rod  124  is located adjacent to the first tab  20  of the clamp  18 . The unclamp rod  124  is attached to a load cell  126  with a coupling  128 . The load cell  126  is attached to an air cylinder  130  with a second coupling  132 . When a switch is engaged, the air cylinder  130  is actuated and the unclamp rod  124  engages the first tab  20  of the clamp  18 . The load cell  126  measures the force applied to the first tab  20  of the clamp  18 . When the clamp  18  snaps to the closed position, force is no longer applied by the unclamp rod  124  to the first tab  20 . When the switch is released, a spring inside the air cylinder  130  returns the unclamp rod  124  and the air cylinder  130  to their respective start positions. If the force measured by the load cell  126  is within a predetermined value range then the clamp  18  has shifted from an open position to a closed position. A successful installation signal is then generated. 
   Referring to  FIG. 8 , another embodiment of a manual hose clamp installation tool is shown. The installation tool  140  is shown with a hook  142  engaging a clamp  18  that is latched in an open position. An unclamp rod  144  is located adjacent to the first tab  20  of the clamp  18 . The unclamp rod  144  is attached to a load cell  146  with a coupling  148 . In this embodiment the unclamp rod  144  does not move to disengage the clamp  18 . Instead, the unclamp rod  144  is used to pry against the first tab  20  of the clamp  18 . The load cell  146  measures the force applied to the first tab  20 . When the clamp  18  snaps to the closed position, force is no longer applied by the unclamp rod  144  to the first tab  20 . If the force measured by the load cell  146  is within a predetermined value range then the clamp  18  has shifted from an open position to a closed position. A successful installation signal is then generated. 
   While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.