Crosshead zero calibration mechanism for injection molding machine

Abstract

The utility model discloses a crosshead zero calibration mechanism for an injection molding machine, which comprises a rack, a control device and a measuring device, and the measuring device is mounted on the rack to measure the moving distance of a second plate; the measuring device is provided with an induction type electronic device, an induction block and a connecting plate, the induction block is fixed on the second plate through the connecting plate, the induction type electronic device is electrically connected with the control device, and the induction type electronic device transmits measured data to the control device to be recorded and processed. The crosshead zero calibration mechanism for the injection molding machine provided by the utility model is simple in structure, the calibration method is simple to operate, and the crosshead zero calibration precision is high; only rough machining is needed to be conducted on the attached planes of the two sides of the crosshead and the inner sides of the tail plate embracing arms, and the problems that the plane machining difficulty is large and the machining cost is high are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molding machines, in particular to a crosshead zero position calibration mechanism and a calibration method for an injection molding machine. Background Art

[0002] The injection molding machine realizes the opening and closing of the mold through the hinge mechanism, crosshead, second plate and clamping mechanism. The hinge mechanism transmits the reciprocating motion of the crosshead to the second plate, thereby realizing the opening and closing of the clamping mechanism. The motion stroke of the crosshead and the second plate is not 1:1 transmission, and there is a complex functional relationship between them. The position information of the second plate can be converted into the position information of the crosshead through the functional relationship, so it is necessary to determine the zero position of the crosshead first.

[0003] If the zero position of the crosshead cannot be accurately determined, the stroke of the two plates will deviate, and then the actual stroke of the two plates will deviate from the set expected stroke, which will seriously affect the position accuracy of the clamping mechanism and the size of the clamping force. It is usually considered that the position of the two plates when the hinge mechanism is straightened is 0, and the crosshead position is also 0 at this time, that is, the crosshead is at zero position.

[0004] At present, the zero position calibration of the crosshead of the existing injection molding machine is achieved by mechanical limit. Figures 1 to 5 As shown, there are finishing planes X on both sides of the crosshead, and corresponding finishing platforms Y are provided on the corresponding tailgate arm. The two dimensions A and B shown in the figure are controlled by finishing to ensure that the machine hinge mechanism is in a straight state when the two planes are stuck together, thereby determining the zero position of the crosshead.

[0005] The disadvantages of the existing method are that the cost of fine machining is too high, and the inner side of the tailgate arm is difficult to machine, it is difficult to ensure that the dimension B reaches the desired tolerance, and this dimension is also difficult to inspect after machining is completed.

[0006] Therefore, it is necessary to solve the above technical problems. Summary of the invention

[0007] In view of the above technical problems, the utility model provides a crosshead zero position calibration mechanism and calibration method for an injection molding machine. The calibration mechanism has a simple structure, the calibration method is easy to operate, and the crosshead zero position calibration has high accuracy. The fitting planes on both sides of the crosshead and the inner side of the tail plate arm only need rough machining, which solves the problems of difficulty in machining the fine machining planes of the crosshead and the tail plate arm, difficulty in inspection and high machining cost.

[0008] To achieve the above purpose, the technical solution of the utility model is:

[0009] A method for zero position calibration of a crosshead for an injection molding machine comprises the steps of:

[0010] Preset zero position, preliminarily determine a crosshead zero position, under which the planes on both sides of the crosshead and the inner plane of the tail plate holding wall have a set gap C;

[0011] Obtaining the target stroke, after the crosshead has traveled a certain distance, calculating the target stroke of the second plate when the crosshead zero position is correct;

[0012] The actual stroke measurement is to measure the actual stroke of the two plates after the crosshead has traveled the above distance;

[0013] Determine the stroke deviation value, calculate the deviation value between the actual stroke and the target stroke, and determine whether the stroke deviation value is within the allowable range. If so, complete the calibration of the crosshead zero position. If not, reversely calculate the correction value of the preset zero position based on the stroke deviation value, and correct the preset zero position.

[0014] The above-mentioned method for calibrating the zero position of the crosshead for the injection molding machine is to correct the zero position of the crosshead on the basis of the preset zero position. After the zero position of the crosshead is calibrated, there is still a certain gap between the planes on both sides of the crosshead and the inner plane of the tail plate arm. It is just fine-tuned back and forth on the originally set gap C. Therefore, the fitting planes on both sides of the crosshead and the inner side of the tail plate arm only need rough machining, and the machining of related matching dimensions does not require very high tolerances, and free tolerances are sufficient. This solves the problems of difficulty in machining the fine-machining planes of the crosshead and the tail plate arm, difficulty in inspection, and high machining costs.

[0015] In a further optimized solution, the target stroke is automatically calculated by a control device, the actual stroke is transmitted to the control device, the stroke deviation value is calculated by the control device, and the control device adjusts the crosshead zero position according to the correction value of the preset zero position. The control device is easy to operate, has a high degree of automation, and has a high position adjustment accuracy.

[0016] Further optimizing the solution, the control device enters a stroke ratio curve table, and the stroke ratio curve table is a functional relationship correspondence table between the crosshead moving distance and the second plate moving distance;

[0017] After the crosshead has traveled a certain distance, the control device calculates the target stroke of the two plates according to the stroke ratio curve table.

[0018] The above travel curve table is formulated based on the principle that the position of the second plate is 0 when the hinge mechanism is straightened, and the position of the crosshead is also 0 at this time, that is, the crosshead is at zero position.

[0019] Further optimizing the scheme, the actual stroke is measured by a measuring device, comprising the steps of:

[0020] S1, in debugging mode, lock the mold at low pressure and slow speed until it cannot be locked. Check whether the planes on both sides of the crosshead and the inner plane of the tail plate arm are close to each other. If not, adjust the mold and retreat a distance before re-locking the mold until they are close to each other.

[0021] S2, when the two side planes of the crosshead and the inner plane of the tailgate arm are in close contact, the value of the crosshead zero position is set to a negative gap C;

[0022] S3, in the debugging mode, the crosshead returns to the preset zero position;

[0023] S4, the value of the measuring device is reset to zero;

[0024] S5, the crosshead moves back a certain distance, the control device calculates the target stroke, the measuring device measures the actual stroke and transmits it to the control device, and the control device calculates the stroke deviation value;

[0025] S6, confirm whether the stroke deviation value is within the allowable range, if so, complete the calibration of the crosshead zero position once, if not, reversely calculate the correction value of the preset zero position according to the stroke deviation value, and control the crosshead to move to the corrected crosshead zero position according to the correction value, and reset the value of the crosshead zero position at this position to zero, and return to step S4 to repeat;

[0026] S7, the crosshead zero position calibration is finally completed only after the crosshead zero position calibration is completed at least twice in succession.

[0027] A crosshead zero position calibration mechanism for an injection molding machine comprises a frame, on which a mold locking mechanism, a crosshead, a machine hinge mechanism, two plates and a tail plate are arranged, the crosshead is connected to the two plates and the tail plate through the machine hinge mechanism, the machine hinge mechanism transmits the reciprocating motion of the crosshead to the two plates to realize the opening and closing of the mold locking mechanism, and is characterized in that it also comprises a control device and a measuring device, the measuring device is installed on the frame to measure the moving distance of the two plates;

[0028] The measuring device is provided with an inductive electronic device, an inductive block and a connecting plate. The inductive block is fixed to the two plates via the connecting plate. The inductive electronic device is electrically connected to the control device. The inductive electronic device transmits the measurement data to the control device for recording and processing.

[0029] According to a further optimization scheme, the control device is an injection molding machine computer.

[0030] According to a further optimized solution, the inductive electronic device is an electronic ruler or a dial indicator.

[0031] According to a further optimized solution, the mold locking mechanism is provided with a head plate, a pull rod, a fixed mold and a movable mold;

[0032] The head plate is fixed on the frame, and the head plate and the tail plate are connected front and back through the pull rod;

[0033] The two plates are slidably mounted on the pull rod; the pull rod constrains the two plates to slide forward and backward thereon;

[0034] The fixed mold is fixed on the head plate, and the movable mold is fixed on the second plate.

[0035] Further optimizing the scheme, the hinge mechanism includes a long hinge, a small hinge, a hook hinge and a plurality of pins;

[0036] The two plates, the long hinge, the hook hinge and the tail plate are sequentially connected head to tail through the pin shaft;

[0037] The middle position of the hook hinge is connected to one end of the small hinge through the pin shaft, and the other end of the small hinge is connected to the cross head through the pin shaft;

[0038] The tail plate is provided with a guide rod, and the cross head is slidably mounted on the guide rod. The guide rod constrains the cross head to slide forward and backward thereon.

[0039] Compared with the prior art, the utility model has the following technical advantages:

[0040] 1. The crosshead zero position calibration method and mechanism used in the injection molding machine solves the problem of difficult machining and high machining cost of the crosshead and tail plate arm finishing plane. The measuring equipment can be reused at a very low cost, which reduces the manufacturing cost of the clamping mechanism;

[0041] 2. The injection molding machine uses the crosshead zero position calibration method and mechanism to realize visual verification of the actual stroke of the two plates. Compared with the previous closed loop that was purely based on trust in processing accuracy, it improves the quality control of the injection molding machine and ensures the consistency of different batches of machines.

[0042] 3. The crosshead zero position calibration mechanism of the injection molding machine greatly improves the position accuracy of the two plates, improves the accuracy of the clamping force, and improves the precision of the injection molding machine;

[0043] 4. The crosshead zero position calibration mechanism for the injection molding machine is easy to operate and has a high degree of automation. The entire process only requires the disassembly and assembly of the measuring equipment, and the rest can be automatically completed by the control equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a three-dimensional diagram of the planes X on both sides of the cross head of the injection molding machine of the utility model and the inner plane Y of the tail plate wall-holding platform;

[0045] Figure 2 yes Figure 1 Stereoscopic view of the middle crosshead;

[0046] Figure 3 yes Figure 2 Side view of

[0047] Figure 4 yes Figure 1 A three-dimensional picture of the center tail board hugging the wall;

[0048] Figure 5 yes Figure 4 Side view of

[0049] Figure 6 It is a type of stroke ratio curve of the crosshead stroke and the second plate stroke of an injection molding machine;

[0050] Figure 7 It is a stereogram of an embodiment of a crosshead zero position calibration mechanism for an injection molding machine of the utility model;

[0051] Figure 8 It is a flow chart of an embodiment of a method for zero position calibration of a crosshead for an injection molding machine of the utility model;

[0052] Fig. 9 It is a data table of zero position calibration of the crosshead of three injection molding machines with different machine body numbers;

[0053] Fig.10 yes Figure 7 State diagram of each mechanism in the middle mold clamping;

[0054] Fig.11 yes Figure 7 State diagram of each mechanism of the middle mold opening;

[0055] Fig.12 yes Figure 7 Schematic diagram of the connection between the middle plate, hinge mechanism, crosshead and tail plate.

[0056] In the figure: frame 10, measuring equipment 20, inductive electronic device 21, inductive block 22, connecting plate 23, second plate 30, crosshead 40, clamping mechanism 50, head plate 51, pull rod 52, fixed mold 53, movable mold 54, machine hinge mechanism 60, long hinge 61, small hinge 62, hook hinge 63, pin shaft 64, tail plate 70, guide rod 71. DETAILED DESCRIPTION

[0057] The present invention will be further described in detail below in conjunction with the embodiments and drawings.

[0058] like Figure 8 As shown, the flow chart is a specific embodiment of a method for calibrating the zero position of a crosshead for an injection molding machine of the utility model. First, a zero position must be preset, and a crosshead zero position must be preliminarily determined. Under the preset zero position, the planes on both sides of the crosshead and the inner plane of the tail plate wall-holding platform have a set gap C.

[0059] like Figures 1 to 5 As shown, Figure 2 and Figure 3 For crosshead, Figure 4 and Figure 5 To hold the tail board against the wall, Figure 1 The planes X on both sides of the middle crosshead can fit with the inner plane Y of the tail plate wall platform. In order to achieve the preset zero position, Figure 3 The A dimension of the crosshead and Figure 5 The B dimension of the middle tail plate wall needs to be processed to achieve the purpose of setting the gap C. The value of the gap C can be an integer within 10. In this embodiment, the gap C is set to 5mm. That is, when the planes X on both sides of the crosshead are in close contact with the inner plane Y of the tail plate wall platform, the crosshead retreats 5mm, and this position is the preset zero position. The preset zero position is not necessarily the real crosshead zero position, and there is a deviation. It is necessary to correct the calibration of the crosshead zero position based on this preset zero position.

[0060] The crosshead zero position calibration method for the injection molding machine requires the use of a control device and a measuring device. The control device calculates the target stroke of the two plates, the measuring device measures the actual stroke of the two plates, the control device calculates the stroke deviation value of the two plates, and the control device reversely calculates the correction value of the preset zero position based on the stroke deviation value of the two plates. Based on this correction value, the control device controls the crosshead to move to the corrected crosshead zero position.

[0061] In this embodiment, the control device is the injection molding machine computer, and the measuring device uses an electronic ruler for measurement. Of course, the measuring device can also be a dial indicator or other device that can measure the position of the two plates.

[0062] The control device, i.e. the injection molding machine computer, needs a stroke ratio curve table when calculating the target stroke of the second plate, such as Figure 6 As shown, the stroke ratio curve table is a functional relationship table between the crosshead moving distance and the second plate moving distance. Figure 6 The stroke ratio curve shown is formulated based on the principle that the position of the second plate is 0 when the hinge mechanism is straightened, and the crosshead position is also 0 at this time, that is, the crosshead is at zero position. The stroke ratio curve table needs to be entered into the injection molding machine computer to facilitate the calculation of the target stroke of the second plate. The injection molding machine computer also needs to set up a zeroing program, that is, a program that resets the crosshead position value and the second plate position value to zero, and set an automatic zeroing button to run the zeroing program.

[0063] like Figure 8 As shown, the specific process of the method for zero position calibration of the crosshead for the injection molding machine of this embodiment is as follows:

[0064] S1, in debugging mode, lock the mold at low pressure and slow speed until it cannot be locked. Check whether the planes on both sides of the crosshead and the inner plane of the tail plate arm are close to each other. If not, adjust the mold and retreat a distance before re-locking the mold until they are close to each other.

[0065] S2, when the two side planes of the crosshead and the inner plane of the tailgate arm are in close contact, the value of the crosshead zero position is set to -5mm;

[0066] S3, in debugging mode, the crosshead returns to the preset zero position;

[0067] S4, the electronic ruler value returns to zero;

[0068] S5, click the auto-zero button on the injection molding machine computer. At this time, the position values ​​of the crosshead, the position values ​​of the electronic ruler and the calculated position values ​​of the second plate are all 0. After the injection molding machine computer controls the crosshead to retreat a certain distance, the injection molding machine computer calculates the target stroke of the second plate. The electronic ruler measures the actual stroke of the second plate and transmits it to the injection molding machine computer. The injection molding machine computer calculates the stroke deviation value between the actual stroke of the second plate and the target stroke.

[0069] S6, confirm whether the stroke deviation value of the second plate is within the allowable range, the range is set to ±0.03mm, and whether the stroke deviation value is less than ±0.03mm; if so, complete a calibration of the crosshead zero position; if not, calculate the correction value of the preset zero position based on the stroke deviation value, and according to this correction value, the computer of the injection molding machine controls the crosshead to move to the corrected crosshead zero position, and resets the value of the crosshead zero position at this position to zero, and returns to step S4 to repeat;

[0070] S7, complete the crosshead zero calibration 5 times in succession, and the crosshead zero calibration is finally completed only when the 5 stroke deviation values ​​meet the requirements. The distance of the crosshead retreating each time must not be the same, and the retreating distance is generally 10%, 15%, 20% of the crosshead stroke, etc. After the crosshead calibration is finally completed, the measuring equipment can be removed.

[0071] like Fig. 9 As shown in the figure, three sets of injection molding machine crosshead zero position calibration data tables with different machine body numbers are listed.

[0072] like Figure 7 As shown, the utility model also discloses a crosshead zero position calibration mechanism for an injection molding machine, including a frame 10, on which a clamping mechanism 50, a crosshead 40, a machine hinge mechanism 60, two plates 30 and a tail plate 70 are provided. The crosshead 40 is connected to the two plates 30 and the tail plate 70 through the machine hinge mechanism 60. The machine hinge mechanism 60 transmits the reciprocating motion of the crosshead 40 to the two plates 30 to realize the opening and closing action of the clamping mechanism 50. The utility model also includes a control device and a measuring device 20. The measuring device 20 is installed on the frame 10 to measure the moving distance of the two plates 30.

[0073] like Figure 7As shown, the measuring device 20 is provided with an inductive electronic device 21, an inductive block 22 and a connecting plate 23. The inductive block 22 is fixed on the second plate 30 through the connecting plate 23. The inductive electronic device 21 is electrically connected to the control device, and the inductive electronic device 21 transmits the measurement data to the control device for recording and processing. The control device is an injection molding machine computer. The inductive electronic device 21 is an electronic ruler or a dial indicator.

[0074] like Figure 7 and Fig.10 As shown, the clamping mechanism 50 is provided with a head plate 51, a tie rod 52, a fixed die 53 and a movable die 54. The head plate 51 is fixed on the frame 10, and the head plate 51 is connected to the tail plate 70 by the tie rod 52. The second plate 30 is slidably mounted on the tie rod 52. The four corners of the second plate 30 are provided with guide post holes. The tie rod 52 passes through the guide post holes to constrain and guide the second plate 30. The second plate 30 can only reciprocate along the tie rod 52. The fixed die 53 is fixed on the head plate 51, and the movable die 54 is fixed on the second plate 30.

[0075] like Figure 7 , Fig.10 and Fig.12 As shown, the hinge mechanism 60 includes a long hinge 61, a small hinge 62, a hook hinge 63 and a plurality of pins 64. The second plate 30, the long hinge 61, the hook hinge 63, the small hinge 62, the crosshead 40 and the tail plate 70 are all provided with reaming holes, and the pins 64 are installed in the reaming holes. The second plate 30, the long hinge 61, the hook hinge 63 and the tail plate 70 are sequentially connected head to tail through the pins 64; that is, the reaming hole on the second plate 30 is connected to the long hinge 61 through the pins 64, the reaming hole on the rear side of the long hinge 61 is connected to the hook hinge 63 through the pins 64, and the reaming hole on the rear side of the hook hinge 63 is connected to the reaming hole on the tail plate 70 through the pins 64.

[0076] like Fig.10 and Fig.12 As shown, the middle reaming hole of the hook hinge 63 is connected to the upper reaming hole of the small hinge 62 through the pin shaft 64, and the lower reaming hole of the small hinge 62 is connected to the reaming hole of the cross head 40 through the pin shaft 64.

[0077] like Fig.12 As shown, a guide rod 71 is provided on the tail plate 70, and the cross head 40 is slidably mounted on the guide rod 71. The cross head 40 is provided with guide rod holes on the left and right sides to be connected with the guide rod 71 on the tail plate 70, and the guide rod 71 constrains the cross head 40 to only slide forward and backward.

[0078] like Fig.10 and Fig.11As shown, the crosshead 40 is mounted on the tail plate 70, guided by the guide rod 71, moves along the guide rod 71, and is powered by the servo motor, and transmitted by the synchronous belt and the ball screw. When the crosshead 40 moves toward the head plate 51, the hinge mechanism 60 will gradually straighten and push the second plate 30 forward; when the crosshead 40 moves toward the tail plate 70, the hinge mechanism 60 will gradually bend and push the second plate 30 backward.

[0079] like Fig.10 and Fig.11 As shown, the main function of the mold clamping mechanism 50 is realized by the reciprocating motion of the second plate 30. The second plate 30 moves toward the head plate 51 until the fixed mold 53 and the movable mold 54 are closed to form a closed mold. Fig.10 The two plates 30 move toward the tail plate 70, and the fixed mold 53 and the movable mold 54 gradually separate to form an open mold. Fig.11 This is the mold opening state.

[0080] The above-mentioned crosshead zero position calibration method and calibration mechanism for the injection molding machine effectively reduce the difficulty and cost of machining the planes on both sides of the crosshead and the inner planes of the tail plate wall-holding platform. The calibration mechanism has a simple structure, the calibration method is easy to operate, and the crosshead zero position positioning accuracy is high, which correspondingly improves the position accuracy of the two plates, thereby improving the overall precision of the injection molding machine.

[0081] In summary, the utility model, as described in the specification and the illustrations, has been used and tested many times. From the test results, it is proved that the utility model can achieve the expected purpose and its practicality is beyond doubt. The above embodiments are only used to facilitate the description of the content of the utility model, and are not intended to be formally limited to it; any equivalent embodiment made by partial changes or modifications made by anyone with common knowledge in the technical field of the utility model without departing from the scope of the technical features and similar features of the utility model, using the technical content disclosed by the utility model, belongs to the protection scope of the utility model.

Claims

1. A crosshead zero position calibration mechanism for an injection molding machine, comprising a frame, on which a mold locking mechanism, a crosshead, a machine hinge mechanism, two plates and a tail plate are arranged, wherein the crosshead is connected to the two plates and the tail plate through the machine hinge mechanism, and the machine hinge mechanism transmits the reciprocating motion of the crosshead to the two plates to realize the opening and closing action of the mold locking mechanism, characterized in that: It also includes a control device and a measuring device, wherein the measuring device is installed on the frame to measure the moving distance of the two plates; The measuring device is provided with an inductive electronic device, an inductive block and a connecting plate. The inductive block is fixed to the two plates via the connecting plate. The inductive electronic device is electrically connected to the control device. The inductive electronic device transmits the measurement data to the control device for recording and processing.

2. The crosshead zero position calibration mechanism for an injection molding machine according to claim 1, characterized in that: The control device is an injection molding machine computer.

3. The crosshead zero position calibration mechanism for an injection molding machine according to claim 1, characterized in that: The inductive electronic device is an electronic ruler or a dial indicator.

4. The crosshead zero position calibration mechanism for an injection molding machine according to any one of claims 1 to 3, characterized in that: The clamping mechanism is provided with a head plate, a pull rod, a fixed mold and a movable mold; The head plate is fixed on the frame, and the head plate and the tail plate are connected front and back through the pull rod; The second plate is slidably mounted on the pull rod; The fixed mold is fixed on the head plate, and the movable mold is fixed on the second plate.

5. The crosshead zero position calibration mechanism for an injection molding machine according to claim 4, characterized in that: The hinge mechanism includes a long hinge, a small hinge, a hook hinge and a plurality of pins; The two plates, the long hinge, the hook hinge and the tail plate are sequentially connected head to tail through the pin shaft; The middle position of the hook hinge is connected to one end of the small hinge through the pin shaft, and the other end of the small hinge is connected to the cross head through the pin shaft; The tail plate is provided with a guide rod, and the cross head is slidably mounted on the guide rod.

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