Door lock with anti-pinch function and capable of automatically closing door in case of power failure

Abstract

A door lock capable of automatically closing a door in power failure and having a hand pinching prevention function comprises a shell of the door lock, a lock catch is installed in the shell, a rack is installed on the rear side of the lock catch, a motor is further installed in the shell, a power failure sampling circuit and an energy storage module are arranged on a circuit board, the power failure sampling circuit and the energy storage module are connected with the input end of a controller, and the power failure sampling circuit is connected with the input end of the controller. The power supply supplies power to the controller and charges the energy storage module, when the power failure sampling circuit detects that the power supply is disconnected, the energy storage module supplies power to the controller, and the controller controls the motor to rotate through the driving circuit and drives the lock catch to retract, so that the door plate is closed. The dishwasher is mainly applied to the dishwasher, the energy storage module can drive the motor to work to enable the door plate of the dishwasher to be automatically closed during accidental power failure, meanwhile, the dishwasher has the functions of preventing hands from being pinched and preventing collision, and if the energy storage module runs out of power, the door plate can be closed by pushing the door plate with hands to enable the clutch wheel to be disengaged. The device has the advantages of being simple in structure, convenient to operate and low in cost, and has good market prospects.

Description

Technical Field

[0001] The utility model relates to an automatic door lock structure, specifically a power-off automatic closing door lock with a pinch prevention function for a dishwasher. Background Art

[0002] When a dishwasher is in use, in case of accidental power-off, the dishwasher door cannot be closed, which is likely to cause accidents. If the dishwasher door is forced to close, the motor will be damaged.

[0003] The Patent Office publicly disclosed on May 28, 2021, a safety door lock and a dishwasher with a safety door lock, with the application number 202110317578.X. A latch arm, a limit block and a driving assembly are arranged in the door lock. The limit block is located outside the latch arm, and the driving assembly is used to drive the limit block. When the door lock is in the unlocked state, the limit block keeps a distance from the latch arm, and the latch arm moves freely; when the door lock is in the locked state, the limit block approaches or abuts against the latch arm to restrict the free movement of the latch arm. This safety door lock can ensure that household appliances (such as dishwashers) are in a safe state where it is not easy to open the door when needed, and at the same time ensure that the good experience of customers in opening and closing the door is not affected. If the safety door lock is in the locked state, even in case of special circumstances where it is necessary to open the door (such as a sudden power-off), the dishwasher door can be forcibly opened without damaging the door lock. This structure keeps a distance between the limit block and the latch arm to make the latch arm move freely, and the limit block approaches or abuts against the latch arm to restrict the free movement of the latch arm. It is necessary to operate the limit block to achieve clutch, which is very troublesome, and the door lock will not automatically drive the door panel to close. Summary of the Invention

[0004] The purpose of the utility model is to provide a door lock that can automatically close the door when powered off for a dishwasher in view of the defects and deficiencies of the above-mentioned prior art.

[0005] The technical solution adopted by the utility model to achieve the above purpose is: the power-off automatic closing door lock with a pinch prevention function includes a housing of the door lock. A lock catch is installed in the housing, and a rack is installed at the rear of the lock catch. A motor is also installed in the housing. A multi-stage transmission wheel is installed between the output shaft of the motor and the rack. A circuit board is arranged in the door lock, and a controller is arranged on the circuit board. The output end of the controller is connected to a driving circuit, and the driving circuit is directly or indirectly connected to the motor; a power-off sampling circuit and an energy storage module are arranged on the circuit board, and the power-off sampling circuit and the energy storage module are connected to the input end of the controller. The power supply supplies power to the controller and charges the energy storage module. When the power-off sampling circuit detects that the power supply is disconnected, the energy storage module supplies power to the controller, and the controller controls the motor to rotate through the driving circuit, driving the lock catch to retract and closing the door panel.

[0006] The described power-off sampling circuit includes resistors R1 and R3, and the power-off sampling circuit is connected to pin 1 of the controller.

[0007] The described energy storage module is an energy storage circuit, and this energy storage circuit includes capacitors C3, C4, C5, C6, resistor R2, and diode D2. The energy storage circuit is connected to the power-off sampling circuit.

[0008] The described energy storage module is a supercapacitor, and this supercapacitor is connected to the power-off sampling circuit.

[0009] The described energy storage module is a rechargeable battery, and this rechargeable battery is connected to the power-off sampling circuit.

[0010] A variable signal acquisition circuit is arranged between the described drive circuit and the motor. This variable signal acquisition circuit is connected to the input end of the controller. After the controller receives the variable signal from the variable signal acquisition circuit, it controls the motor to stop working or rotate in reverse.

[0011] The described variable signal acquisition circuit is a current differential amplification circuit. When the door panel pinches the hand or the outward opening is blocked, the current differential amplification circuit detects an abnormal increase in current. After the controller receives the variable signal, it controls the motor to stop working or rotate in reverse.

[0012] The described variable signal acquisition circuit is a voltage ripple sampling circuit, a radar signal variable circuit, a camera signal acquisition circuit, an infrared signal acquisition circuit, a pressure signal acquisition circuit, a grating signal acquisition circuit.

[0013] One of the transmission wheels in the described multi-stage transmission wheel is a hand-push clutch wheel. This hand-push clutch wheel includes a gear shaft. An upper transmission wheel is installed above the gear shaft. Multiple annularly distributed pawls are arranged below the gear shaft. The outer end of the pawl is a ratchet tooth. A lower transmission wheel is arranged outside the pawl. Multiple tooth grooves are arranged on the inner ring of the lower transmission wheel. After the ratchet tooth meshes with the tooth groove, the upper transmission wheel and the lower transmission wheel of the clutch wheel are synchronized; the described pawl is elastically deformable. The torque difference between the upper transmission wheel and the lower transmission wheel will generate a centripetal component force on the pawl. When the centripetal component force is greater than the elastic force of the pawl, the ratchet tooth disengages from the tooth groove, and the upper transmission wheel and the lower transmission wheel of the clutch wheel are not synchronized.

[0014] One of the multi-stage drive wheels is an anti-pinch clutch wheel, which includes an upper clutch wheel and a lower clutch wheel. The lower clutch wheel is directly or indirectly linked to the output of the motor, and the upper clutch wheel is directly or indirectly linked to the rack. Bottom teeth are provided on the lower surface of the upper clutch wheel, and top teeth are provided on the lower clutch wheel. After the bottom teeth and the top teeth are engaged, the upper clutch wheel and the lower clutch wheel are linked. A compression spring is provided above the upper clutch wheel, and the compression spring gives a downward thrust to the upper clutch wheel; both sides of the top teeth and the bottom teeth are inclined planes. The relative torque between the upper clutch wheel and the lower clutch wheel will generate an upward component force on the upper clutch wheel. When the upward component force is greater than the sum of the compression spring thrust and the gravity of the upper clutch wheel, the upper clutch wheel moves upward, and the bottom teeth and the top teeth are disengaged from each other.

[0015] The utility model is mainly applied to a dishwasher. When there is an accidental power outage, the energy storage module will drive the motor to work, so that the door panel of the dishwasher can be automatically closed. At the same time, it also has the functions of anti-pinch and anti-collision. If the energy storage module runs out of power, the door panel can also be pushed by hand to disengage the clutch wheel and then close the door panel. It has the advantages of simple structure, convenient operation and low cost, and has a good market prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the utility model.

[0017] Figure 2 is a circuit block diagram of the utility model.

[0018] Figure 3 is a circuit diagram of the utility model.

[0019] Figure 4 is a schematic diagram of the installation of the first clutch wheel of the utility model.

[0020] Figure 5 is a schematic structural diagram of the first clutch wheel of the utility model.

[0021] Figure 6 is a schematic diagram of the installation of the second clutch wheel of the utility model.

[0022] Figure 7 is a schematic structural diagram of the second clutch wheel of the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] As Figure 1As shown in the figure, the utility model is a power-off automatic door-closing door lock with a function of preventing pinching hands, mainly used for dishwashers or other electrical appliances. It includes a housing 80 of the door lock, a lock catch 82 is installed in the housing 80, a rack 81 is installed at the rear side of the lock catch 82. When the rack 81 moves after the lock catch 82 is inserted into the lock groove on the door panel, it can drive the door panel to move. A motor 84 is also installed in the housing 80, and a multi-stage transmission wheel 83 is installed between the output shaft of the motor 84 and the rack 81. Therefore, when the motor 84 rotates, it can realize automatic opening and closing of the door.

[0024] As Figure 2 , Figure 3 shown in the figure, a circuit board is provided in the door lock, a controller 50 is provided on the circuit board, the output end of the controller 50 is connected to a driving circuit 60, and the driving circuit 60 is directly or indirectly connected to the motor 84. In the utility model, the driving circuit 60 is connected to pins 16 and 17 of the controller 50. A control button 30 connected to the input end of the controller 50 is also provided on the dishwasher or the electrical appliance. After receiving the instruction of the control button 30, the controller 50 can control the motor 84 to perform corresponding operations. A power-off sampling circuit 70 and an energy storage module 20 are provided on the circuit board, the power-off sampling circuit 70 and the energy storage module 20 are connected to the input end of the controller 50, the power supply 10 supplies power to the controller 50 and charges the energy storage module 20. When the power-off sampling circuit 70 detects that the power supply 10 is disconnected, the energy storage module 20 supplies power to the controller 50, and the controller 50 controls the motor 84 to rotate through the driving circuit 60, driving the lock catch 82 to retract, so that the door panel is closed. The power-off sampling circuit 70 includes resistors R1 and R3, and the power-off sampling circuit 70 is connected to pin 1 of the controller 50, and can detect whether the power supply 10 is disconnected. The energy storage module 20 is an energy storage circuit 21, and the energy storage circuit 21 includes capacitors C3, C4, C5, C6, a resistor R2 and a diode D2. The energy storage circuit 21 is connected to the power-off sampling circuit 70, and the capacitors C3, C4, C5, C6 can store electric energy and release it when power is off.

[0025] The energy storage module 20 can also be a supercapacitor, and the supercapacitor is connected to the power-off sampling circuit 70. The energy storage module 20 can also be a rechargeable battery, and the rechargeable battery is connected to the power-off sampling circuit 70. This can also achieve the same effect.

[0026] A variable signal acquisition circuit 40 is provided between the described drive circuit 60 and the motor 84. This variable signal acquisition circuit 40 is connected to the input end of the controller 50. After receiving the variable signal from the variable signal acquisition circuit 40, the controller 50 controls the motor 84 to stop working or rotate in the reverse direction. The described variable signal acquisition circuit 40 is a current differential amplification circuit 41. When the door panel pinches a hand or the outward opening is blocked, the current differential amplification circuit 41 detects an abnormal increase in current. After receiving the variable signal, the controller 50 controls the motor 84 to stop working or rotate in the reverse direction. Therefore, the power-off automatic door closing door lock with the function of preventing hand pinching also has the functions of preventing hand pinching during door closing and preventing impact during door opening.

[0027] The described variable signal acquisition circuit 40 being a voltage ripple sampling circuit, a radar signal variable circuit, a camera signal acquisition circuit, an infrared signal acquisition circuit, a pressure signal acquisition circuit, or a grating signal acquisition circuit can also enable the power-off automatic door closing door lock with the function of preventing hand pinching to have the functions of preventing hand pinching during door closing and preventing impact during door opening.

[0028] As Figure 4 , Figure 5 shown, one of the transmission wheels in the described multi-stage transmission wheel 83 is a hand-push clutch wheel 90. The hand-push clutch wheel 90 includes a gear shaft 91. An upper transmission wheel 92 is installed above the gear shaft 91. A plurality of annularly and evenly distributed pawls 93 are provided below the gear shaft 91. The outer end of the pawl 93 is a ratchet tooth 94. The pawl 93 is partially bent so that the ratchet tooth 94 on the pawl 93 deviates from the radial direction. The pawl 93 is elastically deformable. Therefore, when the centripetal force applied to the ratchet tooth 94 is greater than the elastic force of the pawl 93, the ratchet tooth 94 can retract inward. A lower transmission wheel 96 is provided outside the pawl 93. A plurality of tooth grooves 97 are provided in the inner circle of the lower transmission wheel 96. After the ratchet tooth 94 meshes with the tooth groove 97, the upper transmission wheel 92 and the lower transmission wheel 96 of the clutch wheel are synchronized. The pawl 93 is provided with 3 - 6 pieces, and the number of tooth grooves 97 is an integer multiple of the number of pawls 93.

[0029] On the side of the tooth groove 97 is a groove inclined surface 98, and on one side of the ratchet tooth 94 is a tooth inclined surface 95. When the groove inclined surface 98 and the tooth inclined surface 95 apply force relatively, a centripetal component force will be generated on the pawl 93. The included angle between the groove inclined surface 98 and the tooth inclined surface 95 and the diameter of the clutch wheel is angle a, and the value range of the included angle a is 20 - 40 degrees. In this embodiment, the value of the included angle a is 27.5 degrees. At this angle, during normal operation, the centripetal component force generated by the torque difference between the upper transmission wheel 92 and the lower transmission wheel 96 on the pawl 93 is less than the elastic force of the pawl 93, which does not affect the normal operation of the door lock. Therefore, the torque difference between the upper transmission wheel 92 and the lower transmission wheel 96 will generate a centripetal component force on the pawl 93. When the centripetal component force is greater than the elastic force of the pawl 93, the ratchet tooth 94 disengages from the tooth groove 97, and the upper transmission wheel 92 and the lower transmission wheel 96 of the clutch wheel are out of sync. The lock catch 82 can be pushed back into the housing 80. It prevents the door from not being able to be closed when the power of the energy storage module 20 is exhausted, improving the safety of use.

[0030] As Figure 6 , Figure 7 shown, one of the transmission wheels in the multi-stage transmission wheel 83 is an anti-pinch clutch wheel 100. The anti-pinch clutch wheel 100 includes an upper clutch wheel 101 and a lower clutch wheel 103. The lower clutch wheel 103 is directly or indirectly linked to the output of the motor 84, and the upper clutch wheel 101 is directly or indirectly linked to the rack 81. A wheel shaft is provided on the housing 80. The upper clutch wheel 101 and the lower clutch wheel 103 are movably sleeved on the wheel shaft, and the upper clutch wheel 101 can slide up and down along the wheel shaft. A bottom surface tooth 102 is provided on the lower surface of the upper clutch wheel 101, and a top surface tooth 104 is provided on the lower clutch wheel 103. After the bottom surface tooth 102 and the top surface tooth 104 are engaged, the upper clutch wheel 101 and the lower clutch wheel 103 are linked. A compression spring is provided above the upper clutch wheel 101. The compression spring is sleeved on the wheel shaft and is supported between the inner wall of the housing 80 and the top surface of the upper clutch wheel 101. The compression spring gives a downward thrust to the upper clutch wheel 101 to ensure the engagement of the bottom surface tooth 102 and the top surface tooth 104.

[0031] Both sides of the top surface tooth 104 and the bottom surface tooth 102 are inclined surfaces. The relative torque between the upper clutch wheel 101 and the lower clutch wheel 103 will generate an upward component force on the upper clutch wheel 101. When the upward component force is greater than the thrust of the compression spring and the gravity of the upper clutch wheel 101, the upper clutch wheel 101 moves upward, and the bottom surface tooth 102 and the top surface tooth 104 disengage from each other.

[0032] Therefore, when opening or closing the door, if there is an obstacle blocking, the rack 81 and the upper clutch wheel 101 will stop moving due to the obstruction, while the lower clutch wheel 103 continues to rotate, increasing the relative torque between the upper clutch wheel 101 and the lower clutch wheel 103. The upward component force on the upper clutch wheel 101 also increases accordingly until the bottom teeth 102 and the top teeth 104 are disengaged, and the lower clutch wheel 103 rotates idly. The upper clutch wheel 101 is not stressed, so the door panel will not continue to press against the obstacle. Mechanically, it plays the role of preventing pinching when closing the door and preventing impact when opening the door. After the obstacle is removed, under the action of the restoring force of the compression spring, the upper clutch wheel 101 resets downward, and the bottom teeth 102 of the upper clutch wheel 101 re-engage with the top teeth 104 of the lower clutch wheel 103.

[0033] The utility model is mainly applied to dishwashers. When there is an accidental power outage, the energy storage module 20 will drive the motor 84 to work, automatically closing the door panel of the dishwasher. At the same time, it also has the functions of preventing pinching and preventing collision. If the energy storage module 20 runs out of power, the door panel can also be pushed by hand to disengage the clutch wheels and then close the door panel. It has the advantages of simple structure, convenient operation and low cost, and has good market prospects.

Claims

1. A power-off automatic door lock with an anti-pinch function, comprising a door lock housing, a lock catch installed in the housing, a rack installed on the rear side of the lock catch, a motor installed in the housing, a multi-stage transmission wheel installed between the output shaft of the motor and the rack, a circuit board arranged in the door lock, a controller arranged on the circuit board, an output end of the controller connected to a drive circuit, and the drive circuit directly or indirectly connected to the motor; characterized in that The circuit board is provided with a power-off sampling circuit and an energy storage module, which are connected to the input end of the controller. The power supply supplies power to the controller and charges the energy storage module. When the power-off sampling circuit detects that the power is disconnected, the energy storage module supplies power to the controller, and the controller controls the motor to rotate through the driving circuit, drives the lock to retract, and closes the door panel.

2. The power-off automatic door closing lock with finger-pinch prevention function according to claim 1 is characterized in that The power-off sampling circuit includes resistors R1 and R3, and the power-off sampling circuit is connected to pin 1 of the controller.

3. The power-off automatic door closing lock with finger pinching prevention function according to claim 1 is characterized in that The energy storage module is an energy storage circuit, which includes capacitors C3, C4, C5, C6, a resistor R2 and a diode D2. The energy storage circuit is connected to the power-off sampling circuit.

4. The power-off automatic door closing lock with finger-pinch prevention function according to claim 3 is characterized in that The energy storage module is a farad capacitor, which is connected to a power-off sampling circuit.

5. The power-off automatic door closing lock with finger-pinch prevention function according to claim 3 is characterized in that The energy storage module is a rechargeable battery, which is connected to the power-off sampling circuit.

6. The power-off automatic door closing lock with finger-pinching prevention function according to any one of claims 1 to 5, characterized in that A variable signal acquisition circuit is provided between the driving circuit and the motor, and the variable signal acquisition circuit is connected to the input end of the controller. After receiving the variable signal from the variable signal acquisition circuit, the controller controls the motor to stop working or rotate in the reverse direction.

7. The power-off automatic door closing lock with finger-pinch prevention function according to claim 6 is characterized in that The variable signal acquisition circuit is a current differential amplifier circuit. When the door panel pinches the hand or is blocked from opening outward, the current differential amplifier circuit detects an abnormal increase in current. After receiving the variable signal, the controller controls the motor to stop working or rotate in the reverse direction.

8. The power-off automatic door closing lock with finger pinch prevention function according to claim 6 is characterized in that The variable signal acquisition circuit is a voltage ripple sampling circuit, a radar signal variable circuit, a camera signal acquisition circuit, an infrared signal acquisition circuit, a pressure signal acquisition circuit, and a grating signal acquisition circuit.

9. The power-off automatic door closing lock with finger-pinching prevention function according to any one of claims 1 to 5, characterized in that One of the multi-stage transmission wheels is a hand-pushed clutch wheel, which includes a gear shaft, an upper transmission wheel is installed above the gear shaft, and a plurality of annularly evenly distributed pawls are arranged below the gear shaft, the outer end of the pawl is a ratchet, and a lower transmission wheel is arranged on the outer side of the pawl, and a plurality of tooth grooves are arranged on the inner ring of the lower transmission wheel. After the ratchet teeth are engaged with the tooth grooves, the upper transmission wheel and the lower transmission wheel of the clutch wheel are synchronized; the ratchet is elastically deformable, and the torque difference between the upper transmission wheel and the lower transmission wheel will generate a centripetal force on the ratchet. When the centripetal force is greater than the elastic force of the ratchet, the ratchet teeth are disengaged from the tooth grooves, and the upper transmission wheel and the lower transmission wheel of the clutch wheel are not synchronized.

10. The power-off automatic door closing lock with finger-pinch prevention function according to any one of claims 1 to 5, characterized in that One of the multi-stage transmission wheels is an anti-pinch clutch wheel, which includes an upper clutch wheel and a lower clutch wheel. The lower clutch wheel is directly or indirectly linked to the output of the motor, and the upper clutch wheel is directly or indirectly linked to the rack. Bottom teeth are arranged on the lower surface of the upper clutch wheel, and top teeth are arranged on the lower clutch wheel. After the bottom teeth and the top teeth are engaged, the upper clutch wheel and the lower clutch wheel are linked. A compression spring is arranged above the upper clutch wheel, and the compression spring gives the upper clutch wheel a downward thrust; both sides of the top teeth and the bottom teeth are inclined surfaces, and the relative torque between the upper clutch wheel and the lower clutch wheel will generate an upward component force on the upper clutch wheel. After the upward component force is greater than the thrust of the compression spring and the gravity of the upper clutch wheel, the upper clutch wheel moves up, and the bottom teeth and the top teeth are disengaged.

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