A road milling machine

Abstract

The present invention relates to a road milling machine, which belongs to the technical field of engineering machinery. The road milling machine includes a power source, a working device and a speed change mechanism. The speed change mechanism includes a power input shaft, a first power output shaft for inputting power to a first transmission mechanism, and a second power output shaft for inputting power to a second transmission mechanism. The first transmission mechanism and the second transmission mechanism are both connected to the working device in a transmission manner. The driving shaft of the power source is connected to the power input shaft, which is connected to the first power output shaft. A driving gear is installed on the power input shaft, which is meshed with a driven gear. The driven gear is installed on the second power output shaft. The first power output shaft and the second power output shaft have different transmission ratios. The first power output shaft is connected to a first clutch, and the second power output shaft is connected to a second clutch. The present invention enables the internal combustion engine to stably operate in an optimal speed range, so that the road milling machine can save energy as much as possible.

Description

Technical Field

[0001] The invention relates to a road milling machine, belonging to the technical field of engineering machinery. Background Art

[0002] Pavement milling machines are specialized machines used for highway and urban road maintenance. They are primarily used for milling asphalt concrete surfaces, roughening cement pavements, and milling offset surfaces in highways, airports, and parking lots. The milling machine's transmission system uses a diesel internal combustion engine as the power source on one end and a milling wheel that rotates around an axis as the working mechanism on the other.

[0003] A common transmission path is that a pulley is directly connected to the internal combustion engine as a driving wheel, and a clutch is placed between the driving wheel and the internal combustion engine to control the on and off of torque transmission. However, in actual work, due to the large differences in construction media, different milling wheel speeds are required. The existing transmission method must adjust the input speed of the milling wheel by changing the speed of the internal combustion engine, which causes the internal combustion engine to often operate in a non-economic speed zone, resulting in energy waste.

[0004] The information disclosed in this background section is only intended to enhance understanding of the overall background of the invention and should not be considered as an admission or any form of suggestion that the information constitutes the prior art already known to a person of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a road milling machine to solve the technical problem in the related art that the input speed of the working device can only be adjusted by changing the speed of the power source, resulting in energy waste.

[0006] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0007] The present invention provides a road milling machine, comprising a power source and a working device, wherein a speed change mechanism is provided between the power source and the working device, the speed change mechanism comprising a power input shaft, a first power output shaft for inputting power to a first transmission mechanism, and a second power output shaft for inputting power to a second transmission mechanism, wherein both the first transmission mechanism and the second transmission mechanism are in transmission connection with the working device;

[0008] The drive shaft of the power source is connected to the power input shaft, and the power input shaft is connected to the first power output shaft. A driving gear is installed on the power input shaft, and the driving gear is meshed and connected with a driven gear. The driven gear is installed on the second power output shaft. The first power output shaft and the second power output shaft have different transmission ratios. The first power output shaft is connected to a first clutch, and the second power output shaft is connected to a second clutch. During operation, either the first clutch or the second clutch can be combined.

[0009] Furthermore, the driving gear is also meshedly connected with a first hydraulic pump driving gear and a second hydraulic pump driving gear, the first hydraulic pump driving gear is transmission-connected to two first hydraulic pumps, and the second hydraulic pump driving gear is transmission-connected to two second hydraulic pumps.

[0010] Furthermore, the driving shaft of the power source and the power input shaft of the speed change mechanism are connected via an elastic coupling.

[0011] Furthermore, the first transmission mechanism and the second transmission mechanism are both in transmission connection with a planetary gear reduction mechanism, and the planetary gear reduction mechanism is in transmission connection with the working device.

[0012] Furthermore, the first transmission mechanism and the second transmission mechanism both adopt a belt transmission mechanism or a chain transmission mechanism.

[0013] Furthermore, the transmission ratios of the first transmission mechanism and the second transmission mechanism are different.

[0014] Furthermore, both the first transmission mechanism and the second transmission mechanism are provided with a tensioning mechanism.

[0015] Furthermore, a braking mechanism is installed in the torque transmission path from the power input shaft of the speed change mechanism to the working device.

[0016] Furthermore, the axis of the power source is arranged parallel to the axis of the working device.

[0017] Furthermore, it also includes a frame, a cabin and a traveling mechanism are installed on the frame, an operating position is installed in the cabin, and a hydraulic motor and a hydraulic cylinder are installed on the traveling mechanism.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention ensures that the power source stably works within the optimal speed range by arranging a speed change mechanism, so that the road milling machine can save energy as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1is a structural schematic diagram of a road milling machine provided by an embodiment of the present invention;

[0021] Figure 2 is a structural diagram of a transmission system provided by an embodiment of the present invention;

[0022] Figure 3 1 is a transmission schematic diagram of a speed change mechanism provided by an embodiment of the present invention;

[0023] In the figure: 1: power source; 2: working device; 3: speed change mechanism; 4: power input shaft; 5: first transmission mechanism; 6: first power output shaft; 7: second transmission mechanism; 8: second power output shaft; 9: driving gear; 10: driven gear; 11: first clutch; 12: second clutch; 13: first hydraulic pump drive gear; 14: second hydraulic pump drive gear; 15: first hydraulic pump; 16: second hydraulic pump; 17: elastic coupling; 18: planetary gear reduction mechanism; 19: frame; 20: cabin; 21: walking mechanism; 22: operating position. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0026] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] like Figures 1 to 3 As shown, this embodiment provides a road milling machine comprising a power source 1 and a working device 2. The power source 1 drives the working device 2 to rotate and mill the road surface. A speed change mechanism 3 is provided between the power source 1 and the working device 2 to transmit torque. The speed change mechanism 3 can change the speed and torque of the power source 1 to achieve the purpose of stably operating the power source 1 at an economical speed, thereby reducing energy consumption.

[0028] In this embodiment, the speed change mechanism 3 includes a power input shaft 4, a first power output shaft 6 for inputting power to the first transmission mechanism 5, and a second power output shaft 8 for inputting power to the second transmission mechanism 7. The first transmission mechanism 5 and the second transmission mechanism 7 are both transmission-connected to the working device 2.

[0029] In this embodiment, the drive shaft of the power source 1 is connected to the power input shaft 4, the power input shaft 4 is connected to the first power output shaft 6, a driving gear 9 is installed on the power input shaft 4, the driving gear 9 is meshed with a driven gear 10, and the driven gear 10 is installed on the second power output shaft 8, the first power output shaft 6 is connected to a first clutch 11, and the second power output shaft 8 is connected to a second clutch 12.

[0030] Specifically, the power input shaft 4 and the first power output shaft 6 change the connection or separation state through the opening and closing of the first clutch 11. This route is the first transmission path. Since there is no transmission part transition in the middle, power is directly transmitted from the power source 1 to the first power output shaft 6, which is the most efficient.

[0031] The second power transmission path of the speed change mechanism 3 is that the power input shaft 4 first changes the speed through the gear pair composed of the driving gear 9 and the driven gear 10 while transmitting power to the second power output shaft 8, and switches the connection or separation state of the second power transmission path by controlling the on and off of the second clutch 12.

[0032] A set of gear pairs is added between the power source 1 and the second power output shaft 8, which reduces the efficiency but has a small impact. It is negligible compared with the efficiency increase when working at the economic speed of the power source 1, and can still effectively reduce energy consumption.

[0033] In this embodiment, the first power output shaft 6 and the second power output shaft 8 do not output power at the same time, that is, when the working device 2 is working, only one of the first clutch 11 and the second clutch 12 can be engaged.

[0034] Specifically, when the first transmission path of the speed change mechanism is working, the first clutch 11 on the first transmission path is engaged, the second clutch 12 is disengaged, and the power input shaft 4 and the first power output shaft 6 of the speed change mechanism 3 are connected in a torque-transmitting manner so as to rotate together and at the same speed.

[0035] When the second power transmission path is working, the second clutch 12 on the second power transmission path is engaged and the first clutch 11 is disengaged. At this time, the power input shaft 4 of the speed change mechanism 3 is connected to the second power output shaft 8 through the driving gear 9 and the driven gear 10 in a torque-transmitting manner so that they rotate together at different speeds.

[0036] When the working device 2 is in different working conditions, it ensures that the power source 1 operates at a stable economic speed, reducing energy consumption and pollution.

[0037] In this embodiment, the first power take-off shaft 6 and the second power take-off shaft 8 have different transmission ratios.

[0038] Specifically, the transmission ratio of the first power output shaft 6 is 1, and the power provided by the power source 1 is not transmitted through any gear in the speed change mechanism 3, but is directly output to the first power output shaft 6 through the power input shaft 4 of the speed change mechanism 3.

[0039] The transmission ratio of the second power output shaft 8 is not equal to 1,

[0040] The transmission ratio of the first power output shaft 6 and the second power output shaft 8 can be adjusted by changing the number of teeth. The number of teeth of the driven gear 10 is greater than the number of teeth of the driving gear 9.

[0041] In this embodiment, the driving gear 9 is also meshedly connected with a first hydraulic pump drive gear 13 and a second hydraulic pump drive gear 14. The first hydraulic pump drive gear 13 is transmission-connected to two first hydraulic pumps 15, and the second hydraulic pump drive gear 14 is transmission-connected to two second hydraulic pumps 16.

[0042] Specifically, the driving gear 9 is used to drive the two first hydraulic pumps 15 and the two second hydraulic pumps 16 to rotate. The engagement and separation of the first clutch 11 and the second clutch 12 are controlled by hydraulic pressure. The two first hydraulic pumps 15 and the two second hydraulic pumps 16 can generate the hydraulic pressure required for the operation of the speed change mechanism 3 through the drive of the power source 1.

[0043] In this embodiment, the driving shaft of the power source 1 and the power input shaft 4 of the speed change mechanism 3 are connected via an elastic coupling 17 .

[0044] Specifically, an elastic coupling 17 can be used to transition between the power source 1 and the speed change mechanism 3, which can reduce the impact load of the working medium on the power source 1 during operation while transmitting power, which is beneficial to improving the reliability of the power source 1.

[0045] In this embodiment, both the first transmission mechanism 5 and the second transmission mechanism 7 are in transmission connection with a planetary gear reduction mechanism 18 , and the planetary gear reduction mechanism 18 is in transmission connection with the working device 2 .

[0046] Specifically, the planetary gear reduction mechanism 18 is used to reduce the input speed of the working device 2 and increase the input torque.

[0047] In this embodiment, both the first transmission mechanism 5 and the second transmission mechanism 7 are belt transmission mechanisms or chain transmission mechanisms.

[0048] In this embodiment, a tensioning mechanism is provided on each of the first transmission mechanism 5 and the second transmission mechanism 7 . The tensioning mechanism is used to provide tensioning force for the first transmission mechanism 5 and the second transmission mechanism 7 .

[0049] If a belt drive mechanism is used, the tensioning mechanism can ensure that the belt has sufficient wrap angle and power transmission capacity; if a chain drive mechanism is used, the tensioning mechanism can prevent poor engagement.

[0050] Specifically, a first driving wheel is installed on the first power output shaft 6 of the speed change mechanism 3, a second driving wheel is installed on the second power output shaft 8, and a driven wheel is installed on the planetary gear reduction mechanism 18. A first belt or a first chain is connected between the first driving wheel and the driven wheel, and a second belt or a second chain is connected between the second driving wheel and the driven wheel.

[0051] In this embodiment, the transmission ratios of the first transmission mechanism 5 and the second transmission mechanism 7 are different.

[0052] Specifically, the diameters of the first driving wheel of the first transmission mechanism 5 and the second driving wheel of the second transmission mechanism 7 are different, so as to further change the transmission ratio according to needs.

[0053] In this embodiment, a brake mechanism is installed in the torque transmission path from the power input shaft 4 of the speed change mechanism 3 to the working device 2 .

[0054] Specifically, the working device 2 can be stopped by a braking device when the torque transmission path is interrupted to avoid reverse transmission of the drag torque.

[0055] In this embodiment, the road milling machine further comprises a frame 19 , on which a cabin 20 and a traveling mechanism 21 are mounted. An operating position 22 is mounted in the cabin 20 , and a hydraulic motor and a hydraulic cylinder are mounted on the traveling mechanism 21 .

[0056] Specifically, the whole machine travels on the road surface where it needs to work. The power source 1 adopts an internal combustion engine and is arranged in the engine room 20 to provide power for the whole machine. The working device 2 rotates around the axis I to mill the road surface. When working, the moving direction of the whole machine is perpendicular to the axis of the working device 2. The axis of the power source 1 is arranged parallel to the axis of the working device 2 to ensure the stability of the power transmission.

[0057] The two first hydraulic pumps 15 and the two second hydraulic pumps 16 are used to provide power to the hydraulic motor to drive the entire machine, and to provide power to the hydraulic cylinder to adjust the milling depth of the entire machine. The entire machine can be controlled by the operator at the operating position 22.

[0058] In this embodiment, even if one of the torque transmission paths is damaged, the working device 2 can still be connected to the power source 1 with the help of another torque transmission path to continue operating. At this time, although the rotational speed of the working device 2 may not be optimal for the current working conditions, compared to the milling machine being completely unable to work, this embodiment can ensure that the working device 2 can still be driven to continue operating in most cases, which greatly improves reliability compared to the existing technology.

[0059] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A road milling machine, characterized in that: The invention comprises a power source (1) and a working device (2), wherein a speed change mechanism (3) is provided between the power source (1) and the working device (2), and the speed change mechanism (3) comprises a power input shaft (4), a first power output shaft (6) for inputting power to a first transmission mechanism (5), and a second power output shaft (8) for inputting power to a second transmission mechanism (7), wherein the first transmission mechanism (5) and the second transmission mechanism (7) are both in transmission connection with the working device (2); The driving shaft of the power source (1) is connected to the power input shaft (4), the power input shaft (4) is connected to the first power output shaft (6), a driving gear (9) is installed on the power input shaft (4), the driving gear (9) is meshed with a driven gear (10), the driven gear (10) is installed on the second power output shaft (8), the first power output shaft (6) and the second power output shaft (8) have different transmission ratios, the first power output shaft (6) is connected to a first clutch (11), the second power output shaft (8) is connected to a second clutch (12), when working, the first clutch (11) and the second clutch (12) are optionally combined; The power input shaft (4) and the first power output shaft (6) are connected or disconnected by the first clutch (11), and this route is the first transmission path, and power is directly transmitted from the power source (1) to the first power output shaft (6); The second power transmission path of the speed change mechanism (3) is that the power input shaft (4) first changes the rotation speed through the gear pair consisting of the driving gear (9) and the driven gear (10) while transmitting power to the second power output shaft (8), and switches the engagement or disengagement state of the second power transmission path by controlling the on and off of the second clutch (12); When the first transmission path of the speed change mechanism (3) is in operation, the first clutch (11) on the first transmission path is engaged, the second clutch (12) is disengaged, and the power input shaft (4) and the first power output shaft (6) of the speed change mechanism (3) are connected in a torque-transmitting manner so as to rotate together and at the same speed; When the second power transmission path is in operation, the second clutch (12) on the second power transmission path is engaged and the first clutch (11) is disengaged. At this time, the power input shaft (4) of the speed change mechanism (3) is connected to the second power output shaft (8) through the driving gear (9) and the driven gear (10) in a torque-transmitting manner, so as to rotate together but at different speeds.

2. The road milling machine according to claim 1, characterized in that The driving gear (9) is also meshedly connected with a first hydraulic pump driving gear (13) and a second hydraulic pump driving gear (14); the first hydraulic pump driving gear (13) is drivingly connected to two first hydraulic pumps (15); and the second hydraulic pump driving gear (14) is drivingly connected to two second hydraulic pumps (16).

3. The road milling machine according to claim 1, characterized in that The drive shaft of the power source (1) and the power input shaft (4) of the speed change mechanism (3) are connected via an elastic coupling (17).

4. The road milling machine according to claim 1, characterized in that The first transmission mechanism (5) and the second transmission mechanism (7) are both in transmission connection with a planetary gear reduction mechanism (18), and the planetary gear reduction mechanism (18) is in transmission connection with the working device (2).

5. The road milling machine according to claim 1, characterized in that The first transmission mechanism (5) and the second transmission mechanism (7) both adopt a belt transmission mechanism or a chain transmission mechanism.

6. The road milling machine according to claim 5, characterized in that The transmission ratios of the first transmission mechanism (5) and the second transmission mechanism (7) are different.

7. The road milling machine according to claim 5, characterized in that Both the first transmission mechanism (5) and the second transmission mechanism (7) are provided with a tensioning mechanism.

8. The road milling machine according to claim 1, characterized in that A braking mechanism is installed in the torque transmission path from the power input shaft (4) of the speed change mechanism (3) to the working device (2).

9. The road milling machine according to claim 1, characterized in that The axis of the power source (1) is arranged parallel to the axis of the working device (2).

10. The road milling machine according to claim 1, characterized in that It also includes a frame (19), a cabin (20) and a traveling mechanism (21) are mounted on the frame (19), an operating position (22) is mounted in the cabin (20), and a hydraulic motor and a hydraulic cylinder are mounted on the traveling mechanism (21).

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