Damper-rod-free end-abnormally-moving hydraulic cylinder

Abstract

The invention discloses a non-damping rod end abnormally-moving hydraulic cylinder, and belongs to the technical field of hydraulic cylinders. According to the damping-rod-end-free abnormally-moving hydraulic cylinder, the structure of the top end of a piston rod of the hydraulic cylinder is improved, and therefore the problem that abnormally-moving damping force is too large can be solved. The device comprises an upper mounting ring, a cylinder barrel and a lower mounting ring, a piston is mounted at the lower end of a piston rod, the upper end of the piston rod is inserted into a guide sleeve, the guide sleeve is fixed to the inner wall of the cylinder barrel, and a circle of annular clamping groove is formed in the top end of the piston rod; and the upper mounting ring is fixedly mounted on the piston rod locking device. The improvement of the invention is that the rod end (generally a section connected with the bottom of the cab, namely one end of the piston rod) can be improved, so that the cab floats up and down in the driving process, and the hydraulic rod does not participate in damping elimination, but the piston rod locking device floats up and down in the cylinder body. Damping is transferred to the piston rod locking device, and the damping value of abnormally moving is far smaller than the damping value of a damping spring of the cab and can be neglected to be zero.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic cylinders. Background Art

[0002] The hydraulic cylinder is the core actuator in the hydraulic system. It can convert hydraulic energy into mechanical energy of linear reciprocating motion and is widely used in heavy-duty vehicles, engineering machinery, metallurgical equipment, aerospace and other fields. In the actual use of the hydraulic cylinder, due to various reasons, the hydraulic cylinder will experience a loss of motion phenomenon. If the damping force is too large during the loss of motion, abnormal noise will be generated or damage to the hydraulic cylinder or other parts will be caused. There are many technologies in the prior art to solve the problem of excessive damping of the loss of motion. Among them, the application of solving the loss of motion problem through oil circuit modification is relatively widespread. It basically adds an auxiliary oil circuit to the cylinder body, and reduces the loss of motion damping force generated by lifting or lowering by replenishing the oil at both ends of the piston. The auxiliary oil circuit of this method is generally set at the bottom of the hydraulic cylinder (that is, the bottom of the cylinder body). Although this method reduces the loss of motion damping force to a certain extent, this loss of motion resistance is related to the frequency and amplitude of the piston movement. When the frequency and amplitude values ​​increase, the loss of motion damping force will still be very large, and due to the complex structure of the bottom of the cylinder body, manufacturing and maintenance will be relatively troublesome. Summary of the invention

[0003] The purpose of the present invention is to provide a non-damping rod-end hydraulic cylinder capable of solving the problem of excessive damping force by improving the structure of the top end of the hydraulic cylinder piston rod.

[0004] The present invention comprises an upper mounting ring, a cylinder barrel and a lower mounting ring, wherein the piston is mounted on the lower end of the piston rod, the upper end of the piston rod is inserted into a guide sleeve, the guide sleeve is fixed on the inner wall of the cylinder barrel, and a ring groove is formed on the top of the piston rod; the upper mounting ring is fixedly mounted on the piston rod locking device; the piston rod locking device: a piston rod yielding guide hole is formed on one side of the locking device housing corresponding to the piston rod, a locking mechanism adjusting yielding hole is formed on the side of the piston rod yielding guide hole, the piston rod yielding guide hole corresponds to the piston rod, a spring hole and an unlocking pin through hole are formed on the side wall position of the locking device housing corresponding to the locking mechanism adjusting yielding hole, and a spring hole and an unlocking pin through hole are formed on the unlocking pin through hole. There is an unlocking pin clamping platform on the outside of the through hole, a pressure spring is placed in the spring hole, and an unlocking pin is placed in the unlocking pin through hole; a movable push rod mechanism is installed in the adjusting and yielding hole of the locking mechanism, and the movable push rod mechanism: a connecting shaft pin is installed on the locking device shell wall on the side of the locking mechanism adjusting and yielding hole, and a rotating push rod is installed in the form of an axis on the connecting shaft pin, one end of the rotating push rod is inserted into the groove of the locking block, and the other end is overlapped on the upper end of the unlocking pin, the lower end of the locking block is overlapped on the upper end of the pressure spring, and the upper end corresponds to the ring groove on the piston rod; an unlocking pin groove corresponding to the unlocking pin clamping platform is opened on the unlocking pin.

[0005] The improvement of the present invention is at the rod end (generally refers to the end connected to the bottom of the cab, that is, the end of the piston rod). Through the improvement of the rod end, when the cab floats up and down during driving, the hydraulic rod will not participate in eliminating damping, but it is completed by the up and down floating of the piston rod locking device in the cylinder body, and the damping is transferred to the piston rod locking device. The damping value of the dynamic is much smaller than the damping value of the shock-absorbing spring of the cab and can be ignored as zero. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a schematic diagram of the overall external structure of the present invention and is in a descending state; Figure 2 The present invention Figure 1 's left view and in a descending state; Figure 3 The present invention Figure 2 AA section view and in a descending state; Figure 4 The present invention Figure 3 A magnified view of part B; Figure 5 The present invention Figure 3 A magnified view of part C; Figure 6 is a cross-sectional view of the housing of the locking device of the present invention; Figure 7 The present invention Figure 6 DD direction schematic diagram; Figure 8 It is a schematic diagram of the unlocking pin structure of the present invention; Fig. 9 It is a cross-sectional view of the upper end of the present invention and is in an ascending state. DETAILED DESCRIPTION

[0007] The present invention is mainly applied to the hydraulic lifting cylinder for lifting and lowering the car cab, and can also be applied to other lifting equipment. The present invention is explained by taking the lifting of the car cab as an example, which includes an upper mounting ring 1, a cylinder barrel 2, and a lower mounting ring 3. The piston is installed at the lower end of the piston rod 4. The upper mounting ring 1 and the lower mounting ring 3 are connected to the bottom of the car cab and the frame respectively. The connection method is the same as that of the existing car cab lifting and lowering hydraulic cylinders. The cylinder barrel 2 is the external body of the entire hydraulic cylinder. See the details. Figure 1 and Figure 2 .

[0008] The general structure of the existing hydraulic cylinder is that the top of the piston rod is directly connected to the upper mounting ring 1, the bottom of the cylinder 2 is connected to the lower mounting ring 3, and the lifting or lowering is completed by adjusting the oil pressure at both ends of the piston inside the cylinder 2.

[0009] The upper end of the piston rod 4 of the present invention is inserted into the guide sleeve 5, the guide sleeve 5 is fixed on the inner wall of the cylinder 2, and a ring groove 6 is formed on the top of the piston rod 4; the upper mounting ring 1 is fixedly mounted on the piston rod locking device.

[0010] The top end of the piston rod 4 of the present invention is different from the top end of the existing piston rod. Figure 3 On the right side, the piston rod 4 of the present invention is not directly connected to the upper mounting ring 1, but is transitioned through a piston rod locking device, see Figure 3 and Fig. 9 ,exist Figure 3 The top end of the middle piston rod 4 is out of contact with the piston rod locking device, and the cab is at the lowest point. Fig. 9 The top end of the middle piston rod 4 is inserted into the piston rod locking device and is in a state of lifting the cab to the highest point.

[0011] The piston rod locking device of the present invention: a piston rod giving way guide hole 13 is opened on the side of the locking device housing 11 corresponding to the piston rod 4, a locking mechanism adjusting giving way hole 18 is opened on the side of the piston rod giving way guide hole 13, the piston rod giving way guide hole 13 corresponds to the piston rod 4, a spring hole 14 and an unlocking pin through hole 16 are opened on the side wall position of the locking device housing 11 corresponding to the locking mechanism adjusting giving way hole 18, an unlocking pin clamping platform 15 is arranged outside the unlocking pin through hole 16, a pressure spring 9 is placed in the spring hole 14, and an unlocking pin 1 is placed in the unlocking pin through hole 16 2. A movable push rod mechanism is installed in the locking mechanism adjustment hole 18. The movable push rod mechanism: a connecting shaft pin 7 is installed on the wall of the locking device housing 11 on the side of the locking mechanism adjustment hole 18, and a rotating push rod 8 is installed in the form of an axis on the connecting shaft pin 7. One end of the rotating push rod 8 is inserted into the groove of the locking block 10, and the other end is overlapped on the upper end of the unlocking pin 12. The lower end of the locking block 10 is overlapped on the upper end of the pressure spring 9, and the upper end corresponds to the ring groove 6 on the piston rod 4; an unlocking pin groove 17 corresponding to the unlocking pin clamping platform 15 is opened on the unlocking pin 12.

[0012] See Figure 6 and Figure 7 The piston rod locking device has a locking device housing 11, one end of the locking device housing 11 is fixedly connected to the upper mounting ring 1, and the other end is provided with a piston rod yielding guide hole 13, the piston rod yielding guide hole 13 corresponds to the top end of the piston rod 4, that is, the top end of the piston rod 4 can be inserted into this hole, and three locking mechanism adjustment yielding holes 18 are provided around the piston rod yielding guide hole 13 of the present invention, see Figure 7A set of unlocking and locking mechanisms are installed in each locking mechanism adjustment hole 18. The unlocking and locking mechanisms include a rotating push rod 8, a locking block 10, a pressure spring 9 and an unlocking pin 12. The rotating push rod 8 is a rod or plate that swings back and forth through the connecting shaft pin 7 as an axis. One end of the rotating push rod 8 is placed on the locking block 10, and the other end is placed on the unlocking pin 12. Its movement is completed by the locking block 10 or the unlocking pin 12. That is to say, Fig. 9 Taking the direction as an example, when the locking block 10 pushes the left end of the rotating push rod 8 to rise, the right end of the rotating push rod 8 presses the unlocking pin 12 to descend, and vice versa. Figure 5 For example, when the unlocking pin 12 pushes the left end of the rotating push rod 8 ( Fig. 9 The right end of the push rod 8 ( Fig. 9 The left end of the piston rod 4 presses the locking block 10 downward. Since the locking block 10 corresponds to the ring groove 6 at the end of the piston rod 4, the locking or unlocking of the piston rod 4 is completed by the locking block 10 entering or exiting the ring groove 6.

[0013] The spring hole 14 of the present invention is a blind groove for placing a pressure spring 9, and the upper end of the pressure spring 9 is pressed under the locking block 10. In this way, when the locking block 10 corresponds to the ring groove 6 at the end of the piston rod 4, the locking block 10 is pushed into the ring groove 6 by elastic force to complete the locking.

[0014] The unlocking pin through hole 16 of the present invention is a through hole, and the unlocking pin 12 ( Figure 8 ) is placed in the unlocking pin through hole 16. In order to prevent the unlocking pin 12 from falling out, corresponding buckles (unlocking pin clamping platform 15 and unlocking pin clamping groove 17) are arranged at corresponding positions, so that the unlocking pin 12 is restricted when extending outward ( Fig. 9 unlocking pin 12 position).

[0015] As the piston rod 4 rises, the piston rod locking device is also pushed up until the piston rod locking device is completely disengaged. When the locking block 10 is placed outside the cylinder 2, that is, in the rising state, under the action of the pressure spring 9, the locking block 10 is pushed into the ring groove 6. At the same time, the left end of the rotating push rod 8 is pushed up with the connecting shaft pin 7 as the axis. At the same time, the right end of the rotating push rod 8 presses the unlocking pin 12 to extend from the unlocking pin through hole 16 until the unlocking pin clamping platform 15 is locked with the unlocking pin clamping groove 17. This state is shown in FIG. Fig. 9 . At this point, the rising state is completed.

[0016] When the piston rod 4 descends, the piston rod locking device is also pulled down until the piston rod locking device enters the cylinder 2. When the unlocking pin 12 touches the side wall of the cylinder 2, it is pushed by the side wall to move into the piston rod locking device. At this time, the unlocking pin 12 presses the right end of the rotating push rod 8 ( Figure 5The left end of the push rod 8 ( Figure 5 At the same time, the left end of the rotating push rod 8 ( Figure 5 The locking block 10 is pressed by the right end of the piston rod 4 and moves downward until it is completely out of the ring groove 6. At this time, the locking block 10 compresses the pressure spring 9. When the locking block 10 is completely out of the ring groove 6, the piston rod locking device is completely released from the piston rod 4. At this time, the piston rod 4 will drop again and will be out of the piston rod giving way guide hole 13, and the piston rod locking device will stop inside the cylinder 2. Figure 5 , at this time the descending state is completed.

[0017] When the car is driving, the cab floats up and down with the ups and downs of the road surface, and the connecting ring 1 and the piston rod locking device also float up and down with the cab. Due to the absence of hydraulic resistance, the damping value of the vibration is much smaller than the damping value of the cab shock absorber spring and can be ignored as zero.

[0018] The guide sleeve 5 in the cylinder 2 of the present invention is a piston rod guide seal and also seals the hydraulic oil in the cylinder 2 to prevent the hydraulic oil in the cylinder 2 from entering the entry area of ​​the piston rod locking device. The piston in the cylinder 2 is the same as the prior art with the piston rod 4 rising or falling, and no further description is given here.

[0019] The principle of eliminating damping in the present invention is: During the driving process, the vehicle often encounters bumpy roads, at which time the cab will float up and down with the bumps. In the original design (piston lever dynamic structure), the hydraulic rod will float up and down with the bumps of the road, and a damping force will be generated during the floating process. This damping force will increase and decrease with the floating speed. When the damping force increases to a certain extent, for example, when it is greater than the shock absorption of the air spring, an abnormal noise will occur, usually a thumping sound.

[0020] Therefore, in order to avoid excessive damping force (theoretically, the smaller the better) during driving, it is an important issue. The present invention reduces the damping force by improving the rod end so that no abnormal noise is generated.

[0021] See Figure 3At this time, the cab is lowered to the lowest state and the vehicle can be driven. When the cab is bumpy, the piston rod locking device of the present invention will follow the floating of the cab at the top inside the cylinder 2, and because the unlocking pin 12 is adopted, only the unlocking pin produces a slight damping when moving up and down, so it can be ignored. Generally, in order not to reduce the contact between the outer wall of the locking device housing 11 of the piston rod locking device and the cylinder 2, the present invention generally adopts three equally divided unlocking pins to complete it. It can be seen that the unlocking pin 12 of the present invention has two functions. First, unlocking the top of the piston rod and the piston rod locking device, and second, reducing damping by contacting the inner wall of the cylinder 2.

Claims

1. A non-damping rod-end hydraulic cylinder, comprising an upper mounting ring (1), a cylinder barrel (2), and a lower mounting ring (3), wherein a piston is mounted at the lower end of a piston rod (4), and characterized in that: The upper end of the piston rod (4) is inserted into the guide sleeve (5), the guide sleeve (5) is fixed on the inner wall of the cylinder (2), and the top of the piston rod (4) is provided with a ring groove (6); the upper mounting ring (1) is fixedly installed on the piston rod locking device; the piston rod locking device: a piston rod clearance guide hole (13) is provided on the side of the locking device housing (11) corresponding to the piston rod (4), a locking mechanism adjustment clearance hole (18) is provided on the side of the piston rod clearance guide hole (13), the piston rod clearance guide hole (13) corresponds to the piston rod (4), a spring hole (14) and an unlocking pin through hole (16) are provided on the side wall of the locking device housing (11) corresponding to the locking mechanism adjustment clearance hole (18), an unlocking pin clamping platform (15) is provided on the outside of the unlocking pin through hole (16), and a locking mechanism adjustment clearance hole (18) is provided on the side of the spring hole. A pressure spring (9) is placed in the locking mechanism (14), and an unlocking pin (12) is placed in the unlocking pin through hole (16); a movable push rod mechanism is installed in the locking mechanism adjustment clearance hole (18), and the movable push rod mechanism: a connecting shaft pin (7) is installed on the wall of the locking device housing (11) on the side of the locking mechanism adjustment clearance hole (18), and a rotating push rod (8) is installed in the form of an axis on the connecting shaft pin (7), one end of the rotating push rod (8) is inserted into the groove of the locking block (10), and the other end is overlapped on the upper end of the unlocking pin (12), the lower end of the locking block (10) is correspondingly overlapped on the upper end of the pressure spring (9), and the upper end corresponds to the ring groove (6) on the piston rod (4); an unlocking pin groove (17) corresponding to the unlocking pin clamping platform (15) is opened in the unlocking pin (12).

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