Starting control circuit for starting control of excavator and excavator
By using a series-parallel circuit design and rationally distributing the resistance in the excavator start-up control circuit, the problem of current overload caused by inconsistent relay resistance was solved, and the service life of the controller port was extended.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-18
- Publication Date
- 2026-03-27
AI Technical Summary
In existing technology, inconsistent relay resistance in the excavator start-up control circuit can lead to current overload or insufficient driving capability, damaging the controller port and shortening its service life.
A series-parallel circuit design is adopted, in which the oil shut-off valve relay with the lowest resistance and the starting relay with a relatively small resistance are connected in series and then connected in parallel with the starting signal relay with a larger resistance. The resistance is reasonably distributed, the starting current is limited, and the controller port is protected.
It effectively controls the current of multiple relays, reduces port heating, extends the life of the controller port, and avoids damage from current overload.
Smart Images
Figure CN224048266U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to engineering machinery technical field especially is related to a starting control circuit and excavator for excavator starting control. BACKGROUND
[0002] The statements in this section merely refer to background art associated with this utility model and do not necessarily constitute the prior art.
[0003] The excavator starting control output is mainly the cooperation of starting loop and controller output. When the whole vehicle presses the starting button, the controller receives the signal of the starting button, judges the control output, drives the relay and then controls the starting motor output to start the starter. The excavator starting whole loop needs to drive multiple relays, and the resistances of the relays in the loop are different, some of which are small and some of which are large.
[0004] In the prior art, multiple relays are usually controlled in parallel or in series. The switching output port of the controller has a rated current limit. When the rated current of the port is exceeded, heat exceeding the heat dissipation capacity of the port will be generated, and the accumulation and repeated action of the heat will cause irreversible damage to the port chip, eventually leading to port burnout and failure. Therefore, if the conventional parallel connection is used, the whole loop resistance is lowered, and according to the characteristics of the parallel circuit, it will cause the loop current to be large at the starting moment of the whole vehicle starting, and the carrying capacity of the controller port is limited, which will cause irreversible damage to the controller port due to the generation of large heat for a long time, thereby shortening the service life of the controller and eventually causing the port to burn out and fail to start. If the conventional series connection is used, the port driving capacity is insufficient. The loop resistance is large and the current is small, which cannot drive the corresponding components to work. In fact, the smaller the load of the loop, the smaller the power used by the port, and the longer the service life of the port.
[0005] Therefore, there is an urgent need for a starting control circuit that can adapt to multiple resistance relays and effectively limit the loop current to prolong the service life of the controller. UTILITY MODEL CONTENT
[0006] In order to solve the problems of the prior art, the utility model provides a starting control circuit for excavator starting control and an excavator, which reasonably distributes the loop resistance, limits the starting current, protects the controller port and prolongs its service life through the loop design of parallel connection and series connection.
[0007] To achieve the above purpose, one or more embodiments of the present disclosure provide the following technical solutions:
[0008] In a first aspect, a starting control circuit for starting control of a excavator is disclosed, and has the features that it comprises a controller, a starting signal relay and a starting circuit.
[0009] The starting circuit comprises a fuel cut-off valve relay, a starting relay and a starter circuit, the controlled end of the fuel cut-off valve relay and the control end of the starting relay are connected in series to form a first branch, and the controlled end of the starting relay is connected to the starter circuit.
[0010] The switch output port of the controller is connected to the control end of the starting signal relay, the controlled end of the starting signal relay is connected to the control end of the fuel cut-off valve relay, and the controlled ends of the starting signal relay, the fuel cut-off valve relay and the starting relay are also connected to the positive pole of the power supply to form a parallel connection of the starting signal relay and the first branch.
[0011] Further, the starting signal relay comprises a starting signal relay coil, a diode connected in parallel to the two ends of the starting signal relay coil, and a starting signal relay contact group.
[0012] The starting signal relay coil and the diode connected in parallel constitute the control end of the starting signal relay, and the starting signal relay contact group constitutes the controlled end of the starting signal relay and comprises a starting signal relay first static contact, a starting signal relay first dynamic contact and a starting signal relay second dynamic contact, the starting signal relay first static contact is connected to the positive pole of the power supply, the starting signal relay second dynamic contact is connected to the control end of the fuel cut-off valve relay, and the starting signal relay first static contact and the first dynamic contact are in an attracted state when the vehicle is not started.
[0013] Further, it further comprises a fuel cut-off valve, which is located in the fuel system of the engine of the excavator, and the fuel cut-off valve comprises a fuel cut-off valve electromagnetic coil, one side of which is connected to the controlled end of the fuel cut-off valve relay and the other side of which is grounded.
[0014] Further, the fuel cut-off valve relay comprises a fuel cut-off valve relay coil and a fuel cut-off valve relay normally open contact group.
[0015] The fuel cut-off valve relay coil constitutes the control end of the fuel cut-off valve relay, one end of which is connected to the controlled end of the starting signal relay and the other end of which is grounded, and the fuel cut-off valve relay normally open contact group constitutes the controlled end of the fuel cut-off valve relay, the fuel cut-off valve relay normally open contact group comprises two contacts in parallel, i.e. a fuel cut-off valve relay first contact and a fuel cut-off valve relay second contact, the fuel cut-off valve relay first contact is connected to the positive pole of the power supply, and the fuel cut-off valve relay second contact is connected to the fuel cut-off valve.
[0016] Further, the starting relay comprises a starting relay coil, a starting relay normally open contact group; the starting relay coil constitutes a control end of the starting relay, one end of which is connected with a controlled end of the oil cut-off valve relay, and the other end is grounded; the starting relay normally open contact group constitutes a controlled end of the starting relay; the starting relay normally open contact group comprises two contacts in parallel: a starting relay first contact and a starting relay second contact; the starting relay first contact is connected with a positive electrode of a power supply, and the starting relay second contact is connected with a starting motor loop control end.
[0017] Further, the starting motor loop comprises a starting control coil, a starting motor loop normally open contact group and a starting motor; the starting control coil constitutes a control end of the starting motor loop, one end of which is connected with a controlled end of the starting relay, and the other end is connected with the starting motor and then grounded; the starting motor loop normally open contact group constitutes a controlled end of the starting motor loop; the starting motor loop normally open contact group comprises two contacts in parallel: a starting motor loop first contact and a starting motor loop second contact; the starting motor loop first contact is connected with a positive electrode of a power supply, and the starting motor loop second contact is connected with the starting motor.
[0018] Further, the starting motor loop first contact is also connected with the controlled end of the starting relay.
[0019] Further, a power supply interface of the controller is connected with the positive electrode of the power supply.
[0020] Further, the resistance of the oil cut-off valve relay is the smallest, the resistance of the starting relay is the second smallest, and the resistance of the starting signal relay is the largest.
[0021] In the second aspect, a kind of excavator is disclosed, and the starting control circuit for the excavator starting control described above is used, and the starting control circuit is arranged in the cab of excavator.
[0022] Compared with the prior art, the utility model has the beneficial effects that:
[0023] 1) the oil cut-off valve relay with the smallest resistance and the starting relay with relatively small resistance are connected in series, and then connected in parallel with the starting signal relay. This connection mode makes the branch circuit resistance formed by the two smaller resistance relays connected in series become larger, and connecting in parallel with the starting signal relay with larger resistance will not lower the resistance. In the starting control circuit of the utility model, when the port drives multiple relay outputs, the resistance can effectively divide voltage when there is too small resistance or too large resistance. The mixed series-parallel connection circuit design of the utility model reasonably distributes the total resistance, avoiding the current overload caused by the low resistance branch in parallel circuit.
[0024] 2) the controller port only needs to output small current to control multiple relays, reduces port heat, and prolongs the service life of the controller port. Attached Figure Description
[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.
[0026] Figure 1 This is a schematic diagram of the starting control circuit used for excavator start-up control in this utility model.
[0027] Figure 1 In the diagram, 1. Controller, 2. Start signal relay, 3. Fuel shut-off valve relay, 4. Starter relay, 5. Fuel shut-off valve, 6. Power supply, 7. Starter circuit, 8. Switch output port, 9. First stationary contact of start signal relay, 10. First moving contact of start signal relay, 11. Second moving contact of start signal relay, 12. First contact of fuel shut-off valve, 13. Second contact of fuel shut-off valve, 14. First contact of starter relay, 15. Second contact of starter relay, 16. First contact of starter circuit, 17. Second contact of starter circuit. Detailed Implementation
[0028] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0030] Example 1
[0031] In a typical embodiment of this utility model, such as Figure 1 As shown, a start-up control circuit for excavator start-up control includes: a controller 1, a start-up signal relay 2, and a start-up circuit. In this embodiment, the power supply voltage is 24V.
[0032] The starting circuit includes an oil cut-off valve relay 3, a starting relay 4, and a starter circuit 7. The controlled terminal of the oil cut-off valve relay 3 is connected in series with the control terminal of the starting relay to form the first branch, and the controlled terminal of the starting relay 4 is connected to the starter circuit 7. The starting circuit is used to start the starter motor.
[0033] The switch output port 8 of the controller 1 is connected to the control end of the starting signal relay 2, the controlled end of the starting signal relay 2 is connected to the control end of the fuel cut-off valve relay 3, and the controlled ends of the starting signal relay 2, the fuel cut-off valve relay 3 and the starting relay 4 are also connected to the positive pole of the power supply, forming the parallel connection of the starting signal relay 2 and the first branch.
[0034] The power supply interface of the controller 1 is connected to the positive pole of the power supply. The controller 1 controls the starting signal relay 2 to realize the control of the fuel cut-off valve relay 3 and the starting relay 4.
[0035] The starting signal relay 2 comprises a starting signal relay coil, a diode connected in parallel to the two ends of the starting signal relay coil, and a starting signal relay contact group. The starting signal relay coil and the diode connected in parallel constitute the control end of the starting signal relay 2. The starting signal relay contact group constitutes the controlled end of the starting signal relay 2 and comprises a starting signal relay first static contact 9, a starting signal relay first moving contact 10 and a starting signal relay second moving contact 11. The starting signal relay first static contact 9 is connected to the positive pole of the power supply, and the starting signal relay second moving contact 11 is connected to the control end of the fuel cut-off valve relay 3. When the vehicle is not started, the starting signal relay first static contact 9 and the starting signal relay first moving contact 10 are in the attracted state. When the vehicle starts, the controller 1 outputs a small current through the switch output port 8, the current enters the starting signal relay coil of the starting signal relay 2, the starting signal relay coil generates a magnetic field after being electrified, the starting signal relay first static contact 9 and the starting signal relay first moving contact 10 are disconnected, the first contact 9 and the second moving contact 11 are attracted, and the starting signal relay 2 becomes the attracted state.
[0036] The starting signal relay 2 controls the starting circuit through a small current. The starting signal relay 2 controls the fuel cut-off valve relay 3 through a small current control signal, and further controls the starting circuit with a large current. In this way, the controller port can be protected from being damaged by a large current directly passing through the controller port. In the embodiment, the size of the small current is less than or equal to 1A, and the size of the large current is about 4A.
[0037] The starting control circuit for the starting control of the excavator provided in the embodiment further comprises a fuel cut-off valve 5 located in the fuel system of the engine of the excavator. The fuel cut-off valve 5 comprises a fuel cut-off valve electromagnetic coil, one side of which is connected to the controlled end of the fuel cut-off valve relay 3 and the other side of which is grounded. When the electromagnetic coil of the fuel cut-off valve 5 is electrified, the spool of the fuel cut-off valve 5 is controlled to move, and the fuel circuit of the engine is opened.
[0038] The oil cut valve relay 3 comprises an oil cut valve relay coil and an oil cut valve relay normally open contact group. The oil cut valve relay coil constitutes the control end of the oil cut valve relay 3, one end of which is connected to the controlled end of the starting signal relay 2, and the other end is grounded. The oil cut valve relay normally open contact group constitutes the controlled end of the oil cut valve relay 3. The oil cut valve relay normally open contact group comprises two parallel contacts: an oil cut valve relay first contact 12 and an oil cut valve relay second contact 13; the oil cut valve relay first contact 12 is connected to the positive pole of the power supply, and the oil cut valve relay second contact 13 is connected to the oil cut valve 5.
[0039] The oil cut valve relay 3 functions to control the state of the oil cut valve, and further controls the opening and closing of the engine fuel oil circuit. When the ignition switch is placed in the "START" position, after the vehicle starts, the oil cut valve relay coil in the oil cut valve relay 3 is energized, thereby causing the oil cut valve relay contact group to be attracted, connecting the power supply 6, and further connecting the starting circuit. The current in the starting circuit is related to the load, and the vehicle voltage / total resistance = starting circuit current. At the same time after the power supply 6 is connected, the electromagnetic coil of the oil cut valve 5 is powered, controlling the spool of the oil cut valve 5 to move, and the engine fuel oil circuit is opened.
[0040] The starting relay 4 comprises a starting relay coil and a starting relay normally open contact group; the starting relay coil constitutes the control end of the starting relay 4, one end of which is connected to the controlled end of the oil cut valve relay 3, and the other end is grounded; the starting relay normally open contact group constitutes the controlled end of the starting relay 4; the starting relay normally open contact group comprises two parallel contacts: a starting relay first contact 14 and a starting relay second contact 15; the starting relay first contact 14 is connected to the positive pole of the power supply, and the starting relay second contact 15 is connected to the control end of the starter circuit 7. After the oil cut valve relay normally open contact group is attracted, the starting relay coil is energized, causing the starting relay normally open contact group to be attracted. The starting relay 4 starts or stops the starter by controlling the on-off of the current.
[0041] The starter circuit 7 comprises a starting control coil, a starter circuit normally open contact group, and a starter; the starting control coil constitutes the control end of the starter circuit 7, one end of which is connected to the controlled end of the starting relay 4, and the other end is connected to the starter and then grounded; the starter circuit normally open contact group constitutes the controlled end of the starter circuit 7; the starter circuit normally open contact group comprises two parallel contacts: a starter circuit first contact 16 and a starter circuit second contact 17; the starter circuit first contact 16 is connected to the positive pole of the power supply, and the starter circuit second contact 17 is connected to the starter. The starter circuit first contact 16 is also connected to the controlled end of the starting relay 4. When the starting relay normally open contact group, which is the controlled end of the starting relay 4, is attracted, the circuit of the starter circuit 7 is turned on, the starter starts to rotate, and further drives the engine to work.
[0042] The loop design of the starting control circuit of the application is that the relay with the smallest resistance is connected in series with another relay with relatively small resistance, and the two are connected in parallel with the relay with the largest resistance. In the embodiment, the relay with the smallest resistance is the fuel cut-off valve relay, the resistance of which is 1.35Ω; the relay with relatively small resistance is the starting relay, the resistance of which is 7.8Ω; and the relay with the largest resistance is the starting signal relay, the resistance of which is 360Ω. The fuel cut-off valve relay and the starting relay are connected in series and then connected in parallel with the starting signal relay. In this way, the resistance of the branch after the two smaller resistances are connected in series is increased, and the parallel connection with the larger resistance does not lower the resistance.
[0043] It should be understood that the relay is divided into a control end and a controlled end, and its working principle is based on electromagnetic induction. The coils in the relay are all electromagnetic coils, the control end of the relay is composed of an electromagnetic coil, and the controlled end is composed of contacts or a contact group. When the current in the input circuit passes through the coil, a magnetic field is generated, the magnetic field attracts the armature, thereby driving the contact to act, and the on-off of the circuit is realized. The current in the input circuit is the pull-in current, which is the minimum current that makes the relay pull in.
[0044] Next, taking the starting of the whole excavator as an example, the working process is introduced:
[0045] When the driver presses the starting button, i.e. the ignition switch is placed in the "START" position, the controller 1 receives the starting signal and starts to execute the starting logic. The controller outputs a small current (the size of the small current ≤1A) to the starting signal relay 2 through the switch output port 8, and the coil of the starting signal relay is powered.
[0046] After the electromagnetic coil of the starting signal relay 2 is powered, the first static contact 9 of the starting signal relay and the second dynamic contact 11 of the starting signal relay are attracted, so that the starting signal relay 2 is attracted. After the starting signal relay 2 is attracted, the coil of the fuel cut-off valve relay is powered, so that the first contact of the fuel cut-off valve relay and the second contact of the fuel cut-off valve relay in the normally open contact group of the fuel cut-off valve relay are simultaneously attracted, so that the fuel cut-off valve relay is attracted. After the fuel cut-off valve relay is attracted, the electromagnetic coil of the fuel cut-off valve 5 is connected to the power supply 6, and the electromagnetic coil of the fuel cut-off valve 5 controls the movement of the spool of the fuel cut-off valve 5, so that the engine fuel circuit is opened.
[0047] At the same time when the fuel cut-off valve relay 3 is attracted, the coil of the starting relay is powered, so that the first contact of the starting relay and the second contact of the starting relay in the normally open contact group of the starting relay are simultaneously attracted, so that the starting control coil in the starter circuit 7 is powered, and then the first contact of the starter circuit and the second contact of the starter circuit in the normally open contact group of the starter circuit are simultaneously attracted, so that the starter circuit is connected in circuit. The current in the power supply 6 flows into the starter circuit, the starter starts to start, and the whole starting circuit is connected in circuit.
[0048] At this time, the fuel oil circuit is opened, fuel oil enters the engine, the starter rotates to work and drives the engine to work, and the vehicle starting is completed.
[0049] Example two
[0050] The embodiment discloses a kind of excavators, the start control circuit for the above-mentioned vehicle starting control of excavator is used.
[0051] The above only is the preferred embodiment of the present application and is not used to limit the present application, and the present application can be variously changed and changed for the person skilled in the art. Any modification, equivalent replacement, improvement etc. within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims
1. A start control circuit for dozer start control, characterized by, The application relates to a controller, a starting signal relay and a starting circuit. The starting circuit comprises a cut-off valve relay, a starting relay and a starter circuit, the controlled end of the cut-off valve relay is connected in series with the control end of the starting relay to form a first branch, and the controlled end of the starting relay is connected to the starter circuit. The switch output port of the controller is connected to the control end of the starting signal relay, the controlled end of the starting signal relay is connected to the control end of the cut-off valve relay, and the controlled ends of the starting signal relay, the cut-off valve relay and the starting relay are all connected to the positive pole of a power supply to form the parallel connection of the starting signal relay and the first branch. The starting signal relay comprises a starting signal relay coil, a diode connected in parallel to the two ends of the starting signal relay coil and a starting signal relay contact group.
2. The start control circuit for dozer start control of claim 1, wherein, The starting signal relay coil and the diode constitute the control end of the starting signal relay, the starting signal relay contact group constitutes the controlled end of the starting signal relay and comprises a starting signal relay first static contact, a starting signal relay first dynamic contact and a starting signal relay second dynamic contact; the starting signal relay first static contact is connected to the positive pole of the power supply, the starting signal relay second dynamic contact is connected to the control end of the cut-off valve relay, and the starting signal relay first static contact and the starting signal relay first dynamic contact are in an attraction state when the whole vehicle is not started. The application further relates to a cut-off valve which is arranged in the engine fuel system of the excavator and comprises a cut-off valve electromagnetic coil, one side of the cut-off valve electromagnetic coil is connected to the controlled end of the cut-off valve relay, and the other side is grounded.
3. The start control circuit for dozer start control of claim 1, wherein, The cut-off valve relay comprises a cut-off valve relay coil and a cut-off valve relay normally-open contact group.
4. The start control circuit for dozer start control of claim 3, wherein, The cut-off valve relay coil constitutes the control end of the cut-off valve relay, one end of the cut-off valve relay coil is connected to the controlled end of the starting signal relay, and the other end is grounded; the cut-off valve relay normally-open contact group constitutes the controlled end of the cut-off valve relay; the cut-off valve relay normally-open contact group comprises two parallel contacts, namely a cut-off valve relay first contact and a cut-off valve relay second contact; the cut-off valve relay first contact is connected to the positive pole of the power supply, and the cut-off valve relay second contact is connected to the cut-off valve. The starting relay comprises a starting relay coil, a starting relay normally-open contact group; the starting relay coil constitutes the control end of the starting relay, one end of the starting relay coil is connected to the controlled end of the cut-off valve relay, and the other end is grounded; the starting relay normally-open contact group constitutes the controlled end of the starting relay; the starting relay normally-open contact group comprises two parallel contacts, namely a starting relay first contact and a starting relay second contact; the starting relay first contact is connected to the positive pole of the power supply, and the starting relay second contact is connected to the control end of the starter circuit.
5. The start-up control circuit for dozer start-up control of claim 1, wherein, 6. The start control circuit for dozer start control of claim 1, wherein, The starter circuit comprises a starting control coil, a starter circuit normally open contact group and a starter; the starting control coil constitutes a control end of the starter circuit, one end of which is connected with a controlled end of a starting relay, and the other end is connected with the starter and then grounded; the starter circuit normally open contact group constitutes a controlled end of the starter circuit; the starter circuit normally open contact group comprises two contacts in parallel, a starter circuit first contact and a starter circuit second contact; the starter circuit first contact is connected with a positive pole of a power supply, and the starter circuit second contact is connected with the starter.
7. The start control circuit for dozer start control of claim 6, wherein, The starter circuit first contact is also connected with the controlled end of the starting relay.
8. The start control circuit for dozer start control of claim 1, wherein, The power supply interface of the controller is connected with the positive pole of the power supply.
9. The start control circuit for dozer travel control as set forth in claim 1, wherein, The resistance of the oil cut-off valve relay is the smallest, the resistance of the starting relay is the second, and the resistance of the starting signal relay is the largest.
10. An excavator characterized by comprising: The starting control circuit for the starting control of the excavator is adopted according to any one of claims 1-9.