Patent Publication Number: US-2023144609-A1

Title: Horizontal assembly press apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese Patent Application No. 110141681, filed on Nov. 9, 2021. 
     FIELD 
     The disclosure relates to a machine tool, and more particularly to a horizontal assembly press apparatus. 
     BACKGROUND 
     A conventional horizontal assembly press machine is to perform a press-fit operation of a workpiece assembly along a horizontal axis. The workpiece assembly includes a main workpiece and first and second workpieces respectively disposed at two opposite sides of the main workpiece along the horizontal axis. The press machine includes a machine base and two press heads respectively disposed at two opposite sides of the machine base and driven to be moved toward each other along the horizontal axis. An operating space is defined among the machine base and the press heads for placing the workpiece assembly therein. The press heads are respectively placed at outboard sides of the first and second workpieces, and are actuated to move close to each other along the horizontal axis so as to press the first and second workpieces to perform the press-fit operation of the first and second workpieces to the main workpiece. 
     In operation, the workpiece assembly is placed in the operating space by an operator, and the operator manually adjusts the first workpiece and the second workpiece for them to be respectively registered with the press heads, and installs auxiliary fixtures on the press heads between the first and second workpieces so as to perform the press-fit operation. However, such manner for aligning the first and second workpieces with the press heads through manual adjustment may cause deflection of the first and second workpieces relative to the main workpiece during the press-fit operation, which results in an installation error. 
     SUMMARY 
     Therefore, an object of the disclosure is to provide a horizontal assembly press apparatus that can alleviate at least one of the drawbacks of the prior art. 
     According to the disclosure, the horizontal assembly press apparatus is for performing a press-fit operation of a workpiece assembly along a horizontal axis. The workpiece assembly includes a main workpiece and first and second workpieces respectively disposed at two opposite sides of the main workpiece along the horizontal axis and rotatable about the horizontal axis relative to the main workpiece. The apparatus includes a machine body unit, two moving units, two camera units, two pressing bed units and a processing unit. The machine body unit includes two main machine bodies which are spaced apart from each other in a left-right direction that is parallel to the horizontal axis, and an operating channel which is defined by and between the two main machine bodies and which extends in a front-rear direction that is perpendicular to the left-right direction for movement of the workpiece assembly therein. The moving units are respectively disposed on the two main machine bodies and at left and right sides of the operating channel, and are movable relative to the main machine bodies in an up-down direction and the front-rear direction. The up-down direction is perpendicular to both the left-right direction and the front-rear direction. Each of the camera units is disposed on a respective one of the two moving units to fetch an image of the workpiece assembly entered the operating channel and output an image signal. The pressing bed units are respectively disposed on the moving units and respectively operated to press the first workpiece and the second workpiece along the horizontal axis toward the main workpiece. The processing unit is in signal connection with the camera units, the moving units and the pressing bed units. The processing unit receives and analyzes the image signals from the camera units, determines a target position of the horizontal axis in the image signals, controls movement of the moving units according to the target position to bring the pressing bed units to the target position, and controls movement of the pressing bed units to respectively press the first workpiece and the second workpiece to perform the press-fit operation of the first and second workpieces to the main workpiece along the horizontal axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings, of which: 
         FIG.  1    is a perspective view illustrating an embodiment of a horizontal assembly press apparatus according to the disclosure; 
         FIG.  2    is a schematic sectional view illustrating the embodiment in a state when a carrying unit reaches a stop point of a predetermined course; 
         FIG.  3    is a block diagram of the embodiment; 
         FIG.  4    is a fragmentary sectional view illustrating the embodiment in a state when two camera units are moved with two moving units to a fetching position; 
         FIG.  5    is a fragmentary sectional view illustrating the embodiment in a state when two pressing bed units are moved with the moving units to a target position; 
         FIG.  6    is a fragmentary sectional view illustrating the embodiment in a state when the pressing bed units perform a press-fit operation of a workpiece assembly; 
         FIG.  7    is a fragmentary sectional view illustrating the embodiment in a state when a first workpiece of the workpiece assembly is rotated by a driving wheel; and 
         FIG.  8    is a fragmentary sectional view illustrating the embodiment in a state when two second range finders are moved with the moving units to the target position for measuring the workpiece assembly. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS.  1  to  3   , an embodiment of a horizontal assembly press apparatus according to the disclosure is for performing a press-fit operation of a workpiece assembly  1  along a horizontal axis (L). The workpiece assembly  1  generally includes a main workpiece  11  and first and second workpieces  12 ,  13  respectively disposed at two opposite sides of the main workpiece  11  along the horizontal axis (L) and rotatable about the horizontal axis (L) relative to the main workpiece  11 . The horizontal assembly press apparatus includes a machine body unit  2 , a carrying unit  3 , a holding unit  4 , two moving units  5 , two camera units  6 , two pressing bed units  7 , a processing unit  8 , a first detecting unit  91  and two second detecting units  92 . 
     With reference to  FIGS.  1  and  4   , in this embodiment, the workpiece assembly  1  is a spinning cycle. The main workpiece  11  includes a frame body  111  and a crank shaft  112  disposed on the frame body  111  and extending along the horizontal axis (L). The first workpiece  12  includes a first crank arm  121  to be mounted on an end of the crank shaft  112 , and a crank disc  122  disposed on the first crank arm  121 . The second workpiece  13  includes a second crank arm  131  to be mounted on an opposite end of the crank shaft  112  along the horizontal axis (L). Before the press-fit operation, the crank shaft  112  has been disposed on the frame body  111 , and the first crank arm  121  and the second crank arm  131  are initially disposed on the crank shaft  112  by an operator. 
     Referring to  FIG.  1   , the machine body unit  2  includes two main machine bodies  21  which are spaced apart from each other in a left-right direction (X) that is parallel to the horizontal axis (L), and an operating channel  22  which is defined by and between the two main machine bodies  21  and which extends in a front-rear direction (Y) that is perpendicular to the left-right direction for movement of the workpiece assembly  1  therein. 
     With reference to  FIGS.  1  and  3   , the carrying unit  3  includes a carrier seat  31  for carrying the workpiece assembly  1  thereon, and a cart  32  which supports the carrier seat  31  thereon and which is in signal connection with the processing unit  8 . The cart  32  is remotely controlled to move along a predetermined course in and from the operating channel  22 . The predetermined course has a predetermined stop point in the operating channel  22 . The cart  32  emits a positioning signal when reaching the stop point. 
     With reference to  FIGS.  2  and  3   , the holding unit  4  includes two positioning sensors  41  spaced apart from each other in the front-rear direction (Y) and in signal connection with the processing unit  8 , and two gripping mechanisms  42  in signal connection with the processing unit  8  and respectively disposed on the two main machine bodies  21  and at the left and right sides of the operating channel  22 , respectively. The positioning sensors  41  are respectively disposed corresponding to front and rear sides of the carrier seat  31  on the stop point so as to detect the front and rear positions of the carrier seat  31 . Each of the positioning sensors  41  has an infrared emitter  411  and an infrared receiver  412  respectively disposed on the main machine bodies  21  and at the left and right sides of the operating channel  22 . The gripping mechanisms  42  are controlled by the processing unit  8  and are extendable from the main machine bodies  21  in the left-right direction (X) toward each other. The processing unit  8  receives the positioning signal and controls the gripping mechanisms  42  to respectively grip on left and right sides of the carrier seat  31  so as to permit the workpiece assembly  1  on the carrier seat  31  to be steadily subjected to the press-fit operation. 
     During the press-fit operation of the workpiece assembly  1 , the infrared emitters  411  are kept emitting infrared light to be received by the infrared receivers  412 . Once one of the infrared receivers  412  does not receive infrared light, it is determined that the carrying unit  3  is moved wrongly and at an improper position. The processing unit  8  thus controls all processing steps to stop them and emits a warning to the operator and a stop signal to the cart  32 . The cart  32  carrying the carrier seat  31  and the workpiece assembly  1  is then retracted from the stop point out of the operating channel  22 . 
     The moving units  5  are respectively disposed on the main machine bodies  21  and at left and right sides of the operating channel  22 , and in signal connection with the processing unit  8 . The moving units  5  are controlled by the processing unit  8  to be movable relative to the main machine bodies  21  in an up-down direction (Z) and the front-rear direction (Y) (see  FIG.  1   ). The up-down direction (Z) is perpendicular to both the left-right direction (X) and the front-rear direction (Y). 
     With reference to  FIGS.  3  and  4   , the camera units  6  are respectively disposed on the moving units  5  and in signal connection with the processing unit  8 . The processing unit  8  controls the moving units  5  to move the camera units  6  to a predetermined fetching position so as to permit the camera units  6  to fetch an image of the workpiece assembly  1  entered the operating channel  22 , and to output an image signal to the processing unit  8 . In the fetching position, the camera units  6  are respectively and substantially aligned with the first and second workpieces  12 ,  13 . 
     With reference to  FIGS.  3 ,  5  and  6   , the pressing bed units  7  are respectively disposed on the moving units  5  and in signal connection with the processing unit  8 . Each pressing bed unit  7  includes a press head  71  which is controlled by the processing unit  8  and extendable toward and retractable from the workpiece assembly  1  in the left-right direction (X). 
     The processing unit  8  is in signal connection with the cart  32 , the holding unit  4 , the camera units  6 , the moving units  5 , the pressing bed units  7 , the first detecting unit  91  and the second detecting units  92 . The processing unit  8  receives and analyzes the image signals from the camera units  6 , determines a target position of the horizontal axis (L) in the image signals, controls the movement of the moving units  5  according to the target position to bring the press heads  71  to the target position, and controls the movement of the press heads  71  to project along the horizontal axis (L) toward the workpiece assembly  1  so as to respectively press the first crank arm  121  and the second crank arm  131  to perform the press-fit operation of the first and second crank arms  121 ,  131  to the crank shaft  112  along the horizontal axis (L). 
     With reference to  FIGS.  3  and  7   , the first detecting unit  91  is disposed on one of the moving units  5  adjacent to the first workpiece  12 , and is in signal connection with the processing unit  8 . The first detecting unit  91  includes a connecting arm  911  having an end which is pivotally connected with a corresponding one of the moving units  5 , a driving wheel  912  disposed to an opposite end of the connecting arm  911 , and a first range finder  913  disposed on the corresponding moving unit  5  to correspond to the first workpiece  12 . After the moving units  5  are controlled by the processing unit  8  to move the pressing bed units  7  to the target position and perform the press-fit operation, the connecting arm  911  is controlled by the processing unit  8  and swung to bring the driving wheel  912  to abut against the crank disc  122  such that the driving wheel  912  is driven to rotate so as to make a rotation of the crank disc  122  relative to the crank shaft  112 . The first range finder  913  is registered with an outer rim of the crank disc  122  and measures a runout of the crank disc  122  during the rotation of the crank disc  122 . The processing unit  8  receives the runout and determines whether it exceeds an error threshold which is preset according to the dimension of the workpiece assembly  1 . The error threshold is about 0.05 mm in this embodiment. The runout refers to a deflection that occurs when the first crank arm  121  is press-fitted with the crank shaft  112 . Specifically, the crank disc  122  is disposed on the first crank arm  121 . The deflection of the crank disc  122  might occur when rotated relative to the crank shaft  112 . The maximum displacement of this deflection along the direction of the horizontal axis (L) is said runout. The crank disc  122  is made from a metal material, and the driving wheel  912  is made of a material with higher friction, such as Mono Cast (MC) nylon. The driving wheel  912  hence can drive rotation of the crank disc  122 . 
     With reference to  FIGS.  3  and  8   , the second detecting units  92  are respectively disposed on the moving units  5  and in signal connection with the processing unit  8 . Each second detecting unit  92  includes a second range finder  921 . After the press-fit operation of the workpiece assembly  1  is completed, the moving units  5  are controlled and moved by the processing unit  8  to bring the second range finders  921  to the target position. Each of the second range finders  921  measures a distance between it and a corresponding one of the first and second crank arms  121 ,  131 . The processing unit  8  then calculates, according to the distances, values of press-fit depth of the first and second crank arms  121 ,  131  relative to the crank shaft  112 , and determines whether such values fall in a predetermined value range. The value range is preset by an operator according to the dimension of the workpiece assembly  1 . 
     For example, the first range finder  913  and the second range finders  921  are laser range finders. 
     With reference to  FIGS.  1  to  3   , in operation, the main workpiece  11  is placed on the carrier seat  31 , and the first crank arm  121  with the crank disc  122  and the second crank arm  131  are initially disposed on two opposite ends of the crank shaft  112  along the horizontal axis (L). Subsequently, the cart  32  with the carrier seat  31  and the workpiece assembly  1  carried thereon is moved in the predetermined course to feed the workpiece assembly  1  in the front-rear direction (Y) into the operating channel  22 , and is stopped moving in the operating channel  22  when reaching the stop point and emits the positioning signal. The processing unit  8 , when receiving the positioning signal, controls the gripping mechanisms  42  to respectively grip on the left and right sides of the carrier seat  31  to hold firmly the carrier seat  31 . 
     Next, with reference to  FIGS.  4  to  6   , the processing unit  8  controls the moving units  5  to move the camera units  6  to the fetching position, the camera units  6  respectively fetch images of the first workpiece  12  and the second workpiece  13  and output image signals to the processing unit  8 . The processing unit  8  receives and analyzes the image signals, and determines a target position of the horizontal axis (L) in the image signals. The processing unit  8  controls the movement of the moving units  5  according to the target position to bring the pressing bed units  7  to the target position, and controls the movement of the press heads  71  to project along the horizontal axis (L) to respectively press the first crank arm  121  and the second crank arm  131  to perform the press-fit operation of the first and second crank arms  121 ,  131  to the crank shaft  112  along the horizontal axis (L). When the press-fit operation has been completed, the processing unit  8  controls the press heads  71  to be respectively retracted back to the moving units  5  along the horizontal axis (L). 
     Next, with reference to  FIG.  7   , the processing unit  8  controls the connecting arm  911  to be swung to bring the driving wheel  912  to abut against the crank disc  122  such that the driving wheel  912  is driven to rotate so as to make a rotation of the crank disc  122  relative to the crank shaft  112 . The first range finder  913  measures the runout of the crank disc  122  during the rotation of the crank disc  122 . If the processing unit  8  determines that the runout exceeds the error threshold, the processing unit  8  will control all processing steps to stop them and will emit a warning to the operator and emit a stop signal to the cart  32  (see  FIG.  2   ). When the cart  32  receives the stop signal, it and the carrier seat  31  and the workpiece assembly  1  thereon are moved along the predetermined course from the stop point and retracted from the operating channel  22 . 
     With reference to  FIG.  8   , when the processing unit  8  determines that the runout does not exceed the error threshold, the processing unit  8  controls the moving units  5  to move them so as to bring the second range finders  921  to the target position, and each of the second range finders  921  measures a distance between it and the corresponding one of the first and second crank arms  121 ,  131 . The processing unit  8  then calculates the values of press-fit depth of the first and second crank arms  121 ,  131  relative to the crank shaft  112 . If the processing unit  8  determines that any of the values of press-fit depth does not fall in the predetermined value range, the processing unit  8  will control all processing steps to stop them and will emit a warning to the operator and emit a stop signal to the cart  32  (see  FIG.  2   ). When the cart  32  receives the stop signal, it and the carrier seat  31  and the workpiece assembly  1  thereon are moved along the predetermined course from the stop point and retracted from the operating channel  22 . If the processing unit  8  determines that the values of press-fit depth fall in the predetermined value range, an ending signal will be emitted to the cart  32  such that the cart  32  is moved along the predetermined course from the stop point and retracted back from the operating channel  22 . 
     As illustrated, with the camera units  6  respectively fetching images of the first and second workpieces  12 ,  13  and outputting image signals to the processing unit  8 , the processing unit  8  receives and analyzes the image signals, determines a target position of the horizontal axis (L) in the image signals, controls the movement of the moving units  5  according to the target position to bring the press heads  71  to the target position, and controls the movement of the press heads  71  to respectively press the first crank arm  121  and the second crank arm  131  to perform the press-fit operation. Moreover, with the first detecting unit  91  measuring the runout of the crank disc  122  during rotation, with the second detecting units  92  measuring the values of press-fit depth of the first and second crank arms  121 ,  131  relative to the crank shaft  112 , and with the processing unit  8  determining whether the runout exceeds the error threshold, and whether the press-fit depths fall in the predetermined value range, the workpiece assembly  1  can be assembled precisely. 
     While the disclosure has been described in connection with what is considered the exemplary embodiment, it is understood that this disclosure is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.