Preheater insulation component missing detection device and detection method

Abstract

A preheater insulation component missing detection device includes: a preheater positioning seat, used to position the preheater to be detected, the preheater positioning seat can form electrical conduction with the shell of the preheater when powered on; a conductive joint, used to power the heating component of the preheater; a conductive joint driving mechanism, connected to the conductive joint, used to drive the conductive joint to contact or separate from the heating component of the preheater; a current detection component, used to apply a test voltage between the conductive joint and the preheater positioning seat, and obtain a detection result about the leakage current between the heating component and the preheater shell; a control device, used to control the operation of the conductive joint driving mechanism and the current detection component, and receive the detection result of the current detection component. The present invention also discloses a detection method for a preheater insulation component missing detection device. The present invention can automatically detect whether the preheater insulation component is missing, has high detection efficiency, and can avoid missed detection.

Description

Technical Field

[0001] The invention relates to an assembly technology for an automobile engine preheater. Background Art

[0002] The engine preheater is mainly composed of a preheater housing, a heating component and a ceramic pad assembly, and the heating component and the ceramic pad assembly are both arranged in the preheater housing. The heating component is positioned on the engine's air intake passage and is connected to a power source. Current flows through the heating component to generate heat, thereby raising the temperature of the surrounding gas. The heating component is usually composed of one or more electric heating belts.

[0003] Figure 1 The structure of an existing engine preheater 9 is shown, which includes a preheater shell. The preheater shell 9A includes a shell 91 and a mounting flange 92. The shell 91 and the mounting flange 92 are made of conductive metal, such as steel or aluminum. A positive terminal 911 and a negative terminal 912 are respectively connected to one end of two electric heating belts 93 on one end of the shell 91 and the mounting flange 92. The positive terminal 911 and the negative terminal 912 are both composed of bolts. Each bolt passes through the first metal gasket 941, the electric heating belt 93, the second metal gasket 942, the first insulating gasket 951, the shell 91, the mounting flange 92, the second insulating gasket 952, the third metal gasket 943 and the nut 96 in sequence. An insulating sleeve 97 is also provided between the bolt and the mounting flange and the shell. Two terminals are respectively connected to the other ends of the two electric heating belts 93 on the other end of the shell 91. The structure of the terminals is also similar to that of the positive terminal 911 and the negative terminal 912. External voltage is applied to the heating belt through the terminal block, so that the heating belt is energized and heated. The insulating components (insulating gasket and insulating sleeve) ensure electrical insulation between the housing, mounting flange and the terminal block.

[0004] When assembling parts on the production line, there may be a phenomenon of missing insulating parts (insulating gaskets or insulating sleeves). After the preheater product with missing insulating gaskets is installed in the engine and powered on, it may cause engine failure or even damage, directly affecting the engine performance and driving safety, and leading to poor user experience and serious economic losses. For preheater products with missing insulating sleeves, if there is a large gap between the terminal and the preheater shell in the initial stage, it will not cause leakage immediately after being installed in the engine and powered on, so it will not show abnormal conditions quickly, but this hidden danger will lurk in the product. With the long-term use of the product, under the action of vibration or other external forces, the gap between the terminal and the preheater shell may become smaller or even electrically contact, resulting in the sudden occurrence of leakage, causing engine failure or even damage, which may cause serious safety accidents during driving. However, for the problem of missing insulating gaskets, the existing technology only detects whether the insulating gaskets of the preheater are missing by manual visual inspection. The manual inspection method is not only costly and inefficient, but also cannot guarantee the inspection quality (for example, the inspector may make a wrong judgment or miss a judgment due to fatigue or error). There is no device or method in the prior art that can automatically detect whether the insulating gasket is missing. It is also difficult to detect the insulating sleeve installed inside by manual visual inspection. There is no device or method in the prior art that can automatically detect whether the insulating sleeve is missing. Summary of the invention

[0005] The first technical problem to be solved by the present invention is to provide a preheater insulation component missing detection device, which can automatically detect whether the preheater insulation gasket is missing, has high detection efficiency, and can avoid missing detection. Furthermore, the second technical problem to be solved by the present invention is to provide a preheater insulation component missing detection device, which can automatically detect whether the preheater insulation sleeve is missing, has high detection efficiency, and can avoid missing detection. The third technical problem to be solved by the present invention is to provide a detection method for the preheater insulation component missing detection device.

[0006] In order to solve the above technical problems, an embodiment of the present invention provides a preheater insulation component missing detection device, comprising: a preheater positioning seat, used to position the preheater to be detected, the preheater positioning seat can form electrical conduction with the shell of the preheater when powered on; a conductive joint, used to energize the heating component of the preheater; a conductive joint driving mechanism, connected to the conductive joint, used to drive the conductive joint to contact or separate from the heating component of the preheater; a current detection component, used to apply a test voltage between the conductive joint and the preheater positioning seat, and obtain a detection result of the leakage current between the heating component and the preheater shell; the detection result is a leakage The current detection value or the result of the current detection component comparing the leakage current detection value with a preset leakage current threshold value; the control device is used to control the operation of the conductive joint driving mechanism and the current detection component, and receive the detection result of the current detection component, and when the detection result is the leakage current detection value, compare the leakage current detection value of the current detection component with the preset leakage current threshold value; if the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold value, the control device determines that the preheater insulation component is missing, and if the leakage current detection value of the current detection component is less than the leakage current threshold value, the control device determines that the preheater insulation component is installed properly.

[0007] Furthermore, the preheater includes a terminal electrically connected to a heating component of the preheater, the terminal is fixed to a housing of the preheater, and the insulating component includes an insulating sleeve arranged outside the terminal; the test voltage is greater than or equal to a breakdown voltage between the terminal and the housing of the preheater when the insulating sleeve is not installed on the terminal and the terminal is located in the middle of the mounting through hole of the terminal, and is less than a breakdown voltage between the terminal and the housing of the preheater when the insulating sleeve is installed on the terminal.

[0008] According to another aspect of the present invention, there is also provided a method for detecting a preheater insulation component missing installation detection device, comprising the following steps:

[0009] Place the preheater to be tested on the preheater positioning seat;

[0010] The control device controls the conductive joint driving mechanism to drive the conductive joint to contact with the heating component of the preheater;

[0011] The control device controls the current detection component to apply a test voltage between the conductive joint and the preheater positioning seat;

[0012] The control device receives the detection result of the current detection component, the detection result is the result of the current detection component comparing the leakage current detection value with the preset leakage current threshold value, or the detection result is the leakage current detection value of the current detection component. When the detection result is the leakage current detection value, the control device compares the leakage current detection value of the current detection component with the preset leakage current threshold value; if the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold value, the control device determines that the preheater insulation component is missing, and if the leakage current detection value of the current detection component is less than the leakage current threshold value, the control device determines that the preheater insulation component is installed properly.

[0013] The present invention achieves at least one of the following beneficial effects:

[0014] 1. The present invention can effectively detect whether the insulating gasket of the preheater is missing, prevent the outflow of defective products, thereby reducing the economic losses caused by rework of defective products and improving the safety of product use;

[0015] 2. The present invention can also effectively detect whether the insulating sleeve of the preheater is missing, prevent the outflow of defective products, thereby reducing the economic losses caused by rework of defective products and improving the safety of product use;

[0016] 3. Compared with the manual detection method, the detection efficiency of the present invention is high and can avoid missed detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 A partial cross-sectional structural schematic diagram of an existing engine preheater is shown.

[0019] Figure 2 A schematic diagram of the appearance of a preheater insulation component missing installation detection device according to an embodiment of the present invention is shown.

[0020] Figure 3 A schematic diagram of the internal structure of a preheater insulation component missing installation detection device according to an embodiment of the present invention is shown, wherein the preheater positioning seat is in a pick-up and place position.

[0021] Figure 4 A schematic structural diagram of a preheater insulation component missing installation detection device according to an embodiment of the present invention is shown, wherein the preheater positioning seat is in a detection position.

[0022] Figure 5 A schematic structural diagram of a conductive joint according to an embodiment of the present invention is shown.

[0023] Figure 6 A schematic diagram of an electrical control system according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] See also Figures 2 to 5 A preheater insulation component missing detection device according to an embodiment of the present invention comprises a base 1, a preheater positioning seat 2, a conductive joint 3, a conductive joint driving mechanism, a current detection component 6 and a control device.

[0026] The preheater positioning seat 2 is arranged on the base 1, and is used to position the preheater 9 to be detected. The preheater positioning seat 2 can form electrical conduction with the shell 9A of the preheater 9 when powered on. In this embodiment, the preheater positioning seat 2 is provided with a positioning groove 20 that matches the shape of the shell of the preheater. The positioning groove 20 is used to accommodate the preheater to be detected, and ensure that the positioning seat 2 is in full contact with the preheater shell 9A. The preheater positioning seat 2 includes a bottom plate 21 and a positioning seat body 22. The bottom end of the positioning seat body 22 is connected to the bottom plate 21, and together defines the above-mentioned positioning groove 20. At least a part of the area where the preheater positioning seat 2 contacts the shell 9A of the preheater 9 is composed of a conductive material or the positioning seat 2 includes a conductive component that contacts the preheater shell 9A, thereby achieving electrical conduction between the preheater positioning seat 2 and the preheater shell 9A. Preferably, at least one of the bottom plate 21 of the positioning seat or the positioning seat body 22 is made of conductive material, thereby further ensuring sufficient electrical contact between the preheater positioning seat and the preheater shell, avoiding missed detection due to improper placement of the preheater and poor electrical contact. Preferably, the bottom plate 21 is made of copper, and when the preheater 9 to be detected is placed in the positioning groove 20, the shell 9A is in direct contact with the bottom plate 21.

[0027] The conductive joint 3 is used to energize the heating component of the preheater. In this embodiment, the heating component of the preheater is an electric belt 93. The conductive joint driving mechanism is connected to the conductive joint 3 and is used to drive the conductive joint 3 to contact or separate from the heating component of the preheater 9.

[0028] In this embodiment, the conductive joint driving mechanism is a lifting mechanism, which is used to drive the conductive joint 3 to rise or fall so that the conductive joint contacts or separates from the heating component of the preheater. The lifting mechanism includes a lifting cylinder 41 and a bracket 42, the bracket 42 is fixed on the base 1, and the lifting cylinder 41 is fixed to the bracket 42.

[0029] Preferably, the conductive joint 3 can be elastically extended and retracted along the axial direction. The conductive joint 3 includes a fixed sleeve 31, a spring 32, a connecting rod 33, a floating joint 34 and a trigger rod 35. The fixed sleeve 31 is fixedly connected to the conductive joint driving mechanism. Specifically, the fixed sleeve 31 is connected to the fixed plate 36, and the fixed plate 36 is connected to the lifting cylinder 41. The spring 32 is arranged in the fixed sleeve 31, and the fixed sleeve 31 is provided with a stopper 37 for limiting the upward movement of the spring 32. The upper end of the spring 32 abuts the stopper 37. In this embodiment, the stopper 37 is composed of an upper cover detachably connected to the upper end of the fixed sleeve 31. The upper end of the connecting rod 33 can be axially movably retained in the fixed sleeve 31 and abuts the lower end of the spring 32. The lower end of the connecting rod 33 extends out of the fixed sleeve 31 and is connected to the floating joint 34. The trigger rod 35 is connected to the other end of the floating joint 34. Due to the presence of the spring 32, when the trigger rod 35 contacts the heating belt 93, if the lifting cylinder 41 continues to move downward, the spring 32 will be compressed, thereby ensuring the contact between the trigger rod and the heating belt while reducing the cylinder stroke control accuracy requirements, thereby avoiding damage to the heating belt. In addition, since the interior of the floating joint is a movable connection, the components at both ends of the floating joint are allowed to swing about 15°, so the trigger rod is allowed to swing about 15°, thereby achieving better contact between the trigger rod and the preheater heating belt.

[0030] The current detection component 6 is used to apply a test voltage between the conductive joint and the preheater positioning seat, and detect the leakage current between the heating component and the preheater housing. During the detection, the positive electrode of the current detection component 6 is connected to the trigger rod 35 of the conductive joint 3, and the negative electrode of the current detection component 6 is electrically connected to the preheater positioning seat 2. In this embodiment, the current detection component 6 is a current tester.

[0031] The control device is used to control the operation of the conductive joint driving mechanism and the current detection component, and to receive the detection result of the current detection component. In this embodiment, the detection result is the result of the current detection component 6 comparing the leakage current detection value (i.e., the magnitude of the detected leakage current) with the preset leakage current threshold value, and the control device directly determines whether the preheater insulation component is missing based on the detection result. In another embodiment, the detection result can also be the leakage current detection value of the current detection component 6 (i.e., the magnitude of the detected leakage current), and the control device compares the leakage current detection value of the current detection component 6 with the preset leakage current threshold value. If the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold value, it is determined that the preheater insulation component is missing, and if the leakage current detection value of the current detection component is less than the leakage current threshold value, it is determined that the preheater insulation component is installed properly.

[0032] If the preheater 9 is not missing an insulating component, the insulation between the various terminals of the preheater and the shell of the preheater is good, and no current loop will be formed between the heating component of the preheater and the shell of the preheater, and no leakage current will be generated. If the preheater is missing an insulating gasket, the terminal missing the insulating gasket and the shell of the preheater are electrically connected, and the positive electrode of the current detection component 6, the heating component, the shell of the preheater, and the negative electrode of the current detection component 6 form a loop, thereby generating a leakage current. The leakage current can be used to ensure that the missing of the insulating gasket is detected. If the preheater is missing an insulating sleeve, the terminal missing the insulating sleeve and the shell can still maintain insulation under low voltage. However, when the current detection component 6 outputs a high voltage (greater than or equal to the breakdown voltage between the wiring terminal and the preheater housing when the preheater is not installed with an insulating sleeve and the wiring terminal is located in the middle of the mounting through hole of the wiring terminal on the preheater housing (the required breakdown voltage is the highest at this time), and lower than the breakdown voltage between the wiring terminal and the preheater housing when the preheater is installed with an insulating sleeve, for example, 500V-1500V;), a conduction circuit is formed between the bolts constituting the wiring terminal and the preheater housing due to the high voltage breakdown, thereby generating a leakage current, and the missing installation of the insulating sleeve can be detected by using the leakage current.

[0033] Furthermore, the preheater insulation component missing detection device of this embodiment further includes a positioning seat driving mechanism, which is used to drive the preheater positioning seat 2 to move between the pick-up and placement position and the detection position. The positioning seat driving mechanism includes a translation cylinder 51 and a connecting rod 52, the translation cylinder 51 is connected to one end of the connecting rod 52, and the other end of the connecting rod 52 is connected to the preheater positioning seat 2. The preheater positioning seat 2 is slidably arranged on a pair of guide rails 11 located on the base 1. The control device is used to control the operation of the positioning seat driving mechanism.

[0034] Furthermore, the preheater insulation component missing detection device of this embodiment further includes an insulation cover 8, which covers the conductive joint and the conductive joint driving mechanism to ensure safety during detection (mainly to prevent high voltage from contacting the human body), and the insulation cover 8 is provided with an opening for the preheater positioning seat 2 to enter and exit. The insulation cover 8 is preferably made of a transparent material, preferably organic glass.

[0035] Furthermore, a start button 13 and a reset button 14 are also provided on the base 1. The start button 13 is used to start the detection, and the reset button 14 is used to control the translation cylinder 51 to reset when unqualified products are detected.

[0036] Please refer to Figure 6In this embodiment, the control device includes a PLC controller 71, the signal input end of the PLC controller 71 is electrically connected to the start button 13 and the reset button 14 respectively, the output end of the PLC controller 71 is electrically connected to the control input end of the lifting cylinder 41 and the translation cylinder 51 respectively, and the PLC controller 71 is communicatively connected to the current tester 6.

[0037] A detection method for a preheater insulation component missing detection device according to an embodiment of the present invention comprises the following steps:

[0038] Place the preheater 9 to be tested on the preheater positioning seat 2;

[0039] The control device controls the conductive joint driving mechanism to drive the conductive joint to contact with the heating component of the preheater;

[0040] The control device controls the current detection component 6 to apply a test voltage between the conductive joint and the preheater positioning seat;

[0041] The control device receives the detection result of the current detection component 6, which is the result of the current detection component comparing the leakage current detection value (i.e. the magnitude of the detected leakage current) with the preset leakage current threshold, or the detection result is the leakage current detection value of the current detection component (i.e. the magnitude of the detected leakage current). When the detection result is the leakage current detection value, the control device compares the leakage current detection value of the current detection component with the preset leakage current threshold; if the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold, the control device determines that the preheater insulation component is missing, and if the leakage current detection value of the current detection component is less than the leakage current threshold, the control device determines that the preheater insulation component is installed properly. Further, the above-mentioned test voltage is greater than or equal to the breakdown voltage between the terminal and the preheater housing 9A when the insulation sleeve 97 is not installed on the terminal and the terminal is located in the middle of the installation through hole of the terminal on the preheater housing, and is less than the breakdown voltage between the terminal and the preheater housing 9A when the insulation sleeve 97 is installed.

[0042] In a specific embodiment, the detection process of the preheater insulation component missing detection device of this embodiment is as follows. The preheater 9 to be detected is placed in the positioning groove 20 of the preheater positioning seat 2 and fixed. The operator operates the start button 13, and the PLC controller 71 controls the translation cylinder 51 to transport the preheater positioning seat 2 from the pick-up and placement position to the detection position. Then, the PLC controller 71 controls the lifting cylinder 41 to drive the conductive joint 3 to move downward, so that the trigger rod 35 contacts the electric belt of the preheater 9, and starts the current tester for testing, and the test voltage is applied to the electric belt. In this embodiment, the test voltage is 850V and the test time is 5s. If there is a problem of missing insulation gasket, the current tester 6 will detect a leakage current exceeding the leakage current threshold; if the insulation sleeve is missing, the high voltage will cause the air between the bolts constituting the preheater terminal and the preheater shell to be broken down, thereby forming a leakage current exceeding the leakage current threshold. In this embodiment, the leakage current threshold is set to 0.5mA. The PLC controller 71 compares the collected test data of the current tester with the leakage current threshold, or the current tester 6 compares the test data with the leakage current threshold and sends the comparison result to the PLC controller 71. If the test value of the current tester is less than the leakage current threshold, the product is judged to be qualified, and the PLC controller 71 sends a qualified signal (such as a green light or a qualified prompt sound) to the outside, controls the lifting cylinder 41 to retract, so that the trigger rod 35 is out of contact with the electric belt, and then controls the translation cylinder 51 to exit the qualified product; if the test value of the current tester is greater than or equal to the leakage current threshold, the product is judged to be unqualified, and the PLC controller 71 sends an alarm signal (such as a red light or a buzzer alarm) to the outside, controls the lifting cylinder 41 to retract, so that the trigger rod 35 is out of contact with the electric belt, but the translation cylinder 51 does not move, and the inspection personnel need to manually press the reset button 14 to exit the unqualified preheater product, and then manually take away the unqualified product and mark it. The above completes the entire test process of a single preheater, and then puts in the next preheater to be tested and repeats the above test process.

[0043] The present invention can effectively detect whether the insulating component of the preheater is missing, prevent the outflow of defective products, thereby reducing the economic loss caused by rework of defective products and improving the safety of product use.

[0044] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A preheater insulation component missing detection device, characterized in that: include: A preheater positioning seat, used for positioning the preheater to be tested, wherein the preheater positioning seat can be electrically connected with the shell of the preheater when powered on; A conductive connector for energizing a heating component of the preheater; A conductive joint driving mechanism, connected to the conductive joint, and used to drive the conductive joint to contact or separate from the heating component of the preheater; A current detection component is used to apply a test voltage between the conductive joint and the preheater positioning seat, and obtain a detection result of a leakage current between the heating component and the preheater housing; the detection result is a leakage current detection value or a result of the current detection component comparing the leakage current detection value with a preset leakage current threshold value; A control device, used for controlling the operation of the conductive joint driving mechanism and the current detection component, and receiving a detection result of the current detection component, and when the detection result is a leakage current detection value, comparing the leakage current detection value of the current detection component with a preset leakage current threshold value; If the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold, the control device determines that the preheater insulation component is missing; if the leakage current detection value of the current detection component is less than the leakage current threshold, the control device determines that the preheater insulation component is installed properly; The preheater comprises a terminal electrically connected to a heating component of the preheater, the terminal being fixed to a housing of the preheater, and the insulating component comprising an insulating gasket and an insulating sleeve disposed outside the terminal; The test voltage is greater than or equal to the breakdown voltage between the wiring terminal and the preheater housing when the wiring terminal is not installed with an insulating sleeve and the wiring terminal is located in the center of the installation through hole of the wiring terminal, and is less than the breakdown voltage between the wiring terminal and the preheater housing when the wiring terminal is installed with an insulating sleeve.

2. The preheater insulation component missing detection device according to claim 1, characterized in that: The conductive joint can be elastically expanded and contracted along the axial direction.

3. The preheater insulation component missing detection device according to claim 1, characterized in that: The conductive joint comprises a fixed sleeve, a spring, a connecting rod, a floating joint and a trigger rod; The fixing sleeve is fixedly connected to the conductive joint driving mechanism; the spring is arranged in the fixing sleeve, and the fixing sleeve is provided with a stopper for limiting the upward movement of the spring, and the upper end of the spring abuts against the stopper; the upper end of the connecting rod can be axially movably retained in the fixing sleeve and abuts against the lower end of the spring, and the lower end of the connecting rod extends out of the fixing sleeve and is movably connected to the trigger rod through a floating joint.

4. The preheater insulation component missing detection device according to any one of claims 1 to 3, characterized in that: The preheater insulation component missing detection device comprises a positioning seat driving mechanism, and the positioning seat driving mechanism is used to drive the preheater positioning seat to move between a taking and placing position and a detection position; The control device is used to control the operation of the positioning seat driving mechanism.

5. The preheater insulation component missing detection device according to claim 1, characterized in that: The conductive joint driving mechanism is a lifting mechanism, and the lifting mechanism is used to drive the conductive joint to rise or fall, so that the conductive joint contacts or separates from the heating component of the preheater at the detection position.

6. The preheater insulation component missing detection device according to claim 1, characterized in that: The preheater positioning seat is provided with a positioning groove which matches the shape of the shell of the preheater, and the positioning groove is used to accommodate the preheater to be tested.

7. The preheater insulation component missing detection device according to claim 1, characterized in that: The preheater positioning seat comprises a bottom plate and a positioning seat body, the bottom end of the positioning seat body is connected to the bottom plate, and at least one of the bottom plate and the positioning seat body is made of conductive material.

8. The preheater insulation component missing detection device according to claim 1, characterized in that: The control device is a PLC controller.

9. The preheater insulation component missing detection device according to claim 4, characterized in that: The preheater insulation component missing installation detection device comprises an insulation cover, which covers the conductive joint and the conductive joint driving mechanism, and the insulation cover is provided with an opening for the preheater positioning seat to enter and exit.

10. The detection method of the preheater insulation component missing detection device according to claim 1, characterized in that: The following steps are involved: Place the preheater to be tested on the preheater positioning seat; The control device controls the conductive joint driving mechanism to drive the conductive joint to contact with the heating component of the preheater; The control device controls the current detection component to apply a test voltage between the conductive joint and the preheater positioning seat; The control device receives a detection result of the current detection component, wherein the detection result is a result of the current detection component comparing a leakage current detection value with a preset leakage current threshold value, or the detection result is a leakage current detection value of the current detection component. When the detection result is a leakage current detection value, the control device compares the leakage current detection value of the current detection component with the preset leakage current threshold value; If the leakage current detection value of the current detection component is greater than or equal to the leakage current threshold, the control device determines that the preheater insulation component is missing; if the leakage current detection value of the current detection component is less than the leakage current threshold, the control device determines that the preheater insulation component is installed properly.

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