A wood splitting machine oil cylinder with a booster rod arranged at the rear end of the double-acting oil cylinder

Abstract

This utility model relates to a hydraulic cylinder for a wood splitter with a booster rod at the rear end of a double-acting hydraulic cylinder. It includes a double-acting hydraulic cylinder, whose movement is controlled by a hydraulic system. An axe for splitting wood is fixed to the front end of the piston rod, and a push plate is fixed to the bed behind the wood. Alternatively, a push plate can be fixed to the front end of the piston rod, with an axe fixed to the bed opposite the push plate. The key feature is a through hole at the rear end of the rear cover, through which the front end of a booster rod extends into the hydraulic cylinder body, while the rear end of the booster rod protrudes outside the rear cover. The rear end of the booster rod receives thrust from other thrusting devices. The double-acting hydraulic cylinder and the thrusting device are respectively fixed to the bed of the wood splitter, or the double-acting hydraulic cylinder and the thrusting device are connected together and then fixed to the bed of the wood splitter. The thrusting device can be a screw thread mechanism or a single-acting hydraulic cylinder, with the piston rod of the single-acting hydraulic cylinder abutting against the tail of the booster rod, or the piston rod of the single-acting hydraulic cylinder and the booster rod being integrally formed.

Description

Technical Field

[0001] This utility model relates to the field of agricultural and forestry machinery and equipment, and in particular to a hydraulic cylinder for a wood splitter with a force-boosting rod at the rear end of a double-acting hydraulic cylinder. Background Technology

[0002] Wood splitters are widely used in the landscaping and timber industries of Europe, America, and Australia, countries rich in timber resources that commonly use wood for cooking and heating. Most wood splitters employ single-stage, single-acting or single-stage, double-acting hydraulic cylinders. The characteristic of splitting wood is that a large force is required initially, but once the initial split is complete, only a smaller force is needed to split the rest of the wood. However, the cylinders in existing wood splitters are designed with a large diameter to meet the initial force requirement. While this provides sufficient force for splitting the initial section, the cylinder becomes too large and wasteful when splitting the remaining portion of the wood. Of course, a larger force output can certainly meet the smaller force requirement, but a larger diameter cylinder results in a slower piston rod extension speed, reducing the efficiency of the wood splitting process. For example, when you start splitting wood, you need a thrust of 100mm diameter hydraulic cylinder. After splitting, only a thrust of 50mm diameter hydraulic cylinder is needed. Of course, a 100mm diameter hydraulic cylinder can certainly meet the needs of subsequent wood splitting work. However, when the input hydraulic oil flow rate remains unchanged, a 100mm diameter hydraulic cylinder will be much slower than a 50mm diameter hydraulic cylinder, which reduces work efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a hydraulic cylinder for a high-efficiency wood splitter that matches the characteristics of wood splitting, allowing for controllable force and speed. When a larger force is required, it outputs a larger force, but at a relatively slower speed; when only a smaller force is needed, it outputs a smaller force, but at a faster speed. This achieves a match between the hydraulic cylinder and the characteristics of wood splitting, enabling it to split larger pieces of wood while also allowing for rapid propulsion, thus improving the production efficiency of wood splitting.

[0004] To achieve the above objectives, the present invention is characterized by comprising a cylinder body, in which a piston and a piston rod are installed. A front cover and a rear cover are fixed to the front and rear ends of the cylinder body. The piston rod extends out of the cylinder body through the front cover. An inlet / outlet port and a rear inlet / outlet port are respectively provided at the front and rear ends of the cylinder body, forming a double-acting cylinder. The action of the double-acting cylinder is controlled by a hydraulic system. An axe for splitting wood is fixed to the front end of the piston rod, and a push plate is fixed to the bed behind the wood, or a push plate is fixed to the front end of the piston rod, with a [missing information - likely a device or component] fixed to the bed opposite the push plate. The axe is characterized by a through hole at the rear end of the rear cover, through which the front end of a force-boosting rod extends into the cylinder body, while the rear end of the force-boosting rod protrudes outside the rear cover. The rear end of the force-boosting rod receives thrust from other thrusting devices. The double-acting cylinder and the thrusting device are respectively fixed to the bed of the wood splitter, or the double-acting cylinder and the thrusting device are connected together and then fixed to the bed of the wood splitter. The thrusting device refers to a screw thread mechanism or a single-acting cylinder, in which the piston rod of the single-acting cylinder abuts against the tail of the force-boosting rod, or the piston rod of the single-acting cylinder and the force-boosting rod are integrated.

[0005] The aforementioned lead screw thread mechanism includes a connecting bracket, a nut fixed at the tail of the connecting bracket, a lead screw threaded in the nut that matches the nut thread, a force-applying handle fixed at the tail end of the lead screw to facilitate its rotation, a front part of the connecting bracket connected to a double-acting hydraulic cylinder via a rear cover, and the front end of the lead screw abutting against the rear end of the force-applying rod.

[0006] The hydraulic system controlling the double-acting cylinder includes a hydraulic pump, a relief valve, and a three-position four-way control valve for controlling the inflow and outflow of hydraulic oil into and out of the cylinder.

[0007] The hydraulic transmission device for the single-acting cylinder includes a single-acting cylinder body, a single-acting piston installed in the single-acting cylinder body, the front end of the single-acting piston being the piston rod or booster rod of the single-acting cylinder, and a single-acting inlet / outlet oil port formed at the rear end of the single-acting cylinder body, thus forming a single-acting cylinder, and a hydraulic system for controlling the single-acting cylinder.

[0008] The single-acting hydraulic cylinder is connected to the rear cover via a flange located at the front of the single-acting hydraulic cylinder body.

[0009] The hydraulic system controlling the double-acting and single-acting cylinders includes a hydraulic pump, a relief valve, and a three-position four-way control valve for controlling the inflow and outflow of hydraulic oil into and out of the cylinder body.

[0010] When the thrust device connected to the rear end of the double-acting cylinder is a single-acting cylinder, a deep hole is made at the tail of its piston rod. The diameter of the deep hole is larger than the diameter of the front end of the booster rod or the piston rod of the single-acting cylinder that extends into the cylinder body. The front end of the booster rod or the piston rod of the single-acting cylinder can extend into the deep hole, and the booster rod or the piston rod of the single-acting cylinder does not contact the piston rod.

[0011] The hydraulic system controlling the double-acting cylinder and the hydraulic system controlling the single-acting cylinder share a single hydraulic pump.

[0012] The single-acting cylinder has a vent hole at its front end, and a scale that can move up and down is inserted into the vent hole. The lower end of the scale extends slightly into the single-acting cylinder body, and an inclined surface is formed at the front end of the single-acting piston.

[0013] The stroke of the single-acting hydraulic cylinder is shorter than that of the double-acting hydraulic cylinder.

[0014] Based on the above design, a hydraulic cylinder for a wood splitter with a booster rod at the rear end of a double-acting cylinder is used. Compared to existing wood splitters with only one double-acting cylinder, its cylinder diameter is much smaller, resulting in a significantly faster operating speed while maintaining the same pump displacement. At the start of splitting, a large thrust is required. When the tail end of the double-acting cylinder is connected to a threaded mechanism, rotating the screw allows the piston rod of the double-acting cylinder to receive the combined thrust of the double-acting cylinder and the threaded mechanism, resulting in a larger output force. When the tail end of the double-acting cylinder is connected to a hydraulic booster device for a single-acting cylinder, hydraulic oil simultaneously enters both the double-acting and single-acting cylinders, causing both cylinders to work together, resulting in a larger thrust output from the piston rod of the double-acting cylinder. After the wood is split, hydraulic oil is concentrated on the double-acting cylinder, accelerating the piston rod's advance speed, thus matching the cylinder's characteristics with the wood splitting requirements. Specifically, when the booster rod is in direct contact with the piston rod of the double-acting cylinder, the remaining force from the booster rod, after overcoming the hydraulic pressure within the cylinder, acts directly on the piston rod. This results in the piston rod's output force being the sum of the cylinder's own force and the booster rod's force, making the output force greater than without the booster rod. When the booster rod is not in contact with the piston rod, its extended end within the cylinder alters the volume between the cylinder's rear cover and the piston, increasing the cylinder's pressure. This increased pressure further enhances the piston rod's output force. This structure achieves the following: a larger force is output at the start of splitting wood, and a smaller thrust is used after the wood has split, allowing for rapid axe advancement and improving efficiency in wood splitting. In addition, compared with traditional wood splitters, the manufacturing cost of wood splitters has been reduced and they are more competitive in the market because they use a smaller double-acting cylinder diameter and a smaller oil pump displacement while maintaining the same maximum wood splitting thrust (or even higher). Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a wood splitter with a double-acting hydraulic cylinder, a lead screw and threaded mechanism, and the front end of the force-boosting rod pressing against the piston rod.

[0016] Figure 2This is a schematic diagram of a double-acting hydraulic cylinder with a lead screw thread mechanism at the rear, where the front end of the force-increasing rod does not press against the piston rod.

[0017] Figure 3 yes Figure 2 A three-dimensional image;

[0018] Figure 4 This is a schematic diagram of a structure in which a single-acting cylinder is added after a double-acting cylinder, and the piston rod of the single-acting cylinder is integrated with the force-multiplying rod, while the piston rod of the single-acting cylinder abuts against the piston rod of the double-acting cylinder.

[0019] Figure 5 This is a schematic diagram of a structure in which a single-acting cylinder is added after a double-acting cylinder, and the piston rod of the single-acting cylinder is integrated with the force-boosting rod, while the piston rod of the single-acting cylinder does not press against the piston rod of the double-acting cylinder.

[0020] In the diagram: 1. Cylinder body; 2. Piston; 3. Piston rod; 4. Front cover; 5. Rear cover; 6. Inlet / outlet port; 7. Rear inlet / outlet port; 8. Double-acting cylinder; 9. Wood; 10. Axe; 11. Bed; 12. Push plate; 13. Through hole; 14. Force extender; 15. Lead screw mechanism; 16. Connecting bracket; 17. Nut; 18. Lead screw; 19. Force extension handle; 20. Single-acting cylinder; 21. Single-acting cylinder body; 22. Single-acting piston; 23. Piston rod of single-acting cylinder; 24. Single-acting inlet / outlet port; 25. Hydraulic pump; 26. Relief valve; 27. Three-position four-way control valve; 28. Flange; 29. ​​Vent; 30. Scale; 31. Inclined surface; 32. Deep hole; 33. Hydraulic check valve; 34. M-type three-position four-way control valve. Detailed Implementation

[0021] The following description, in conjunction with the accompanying drawings and specific embodiments, further describes a utility model of a hydraulic cylinder for a wood splitter, which has a force-boosting rod at the rear end of a double-acting hydraulic cylinder.

[0022] Example 1

[0023] This structure is a double-acting hydraulic cylinder with a lead screw thread mechanism. Figure 1 , Figure 2 , Figure 3This is a schematic diagram of its structure. As shown, it includes a cylinder body 1, in which a piston 2 and a piston rod 3 are installed. A front cover 4 and a rear cover 5 are fixed to the front and rear ends of the cylinder body 1. The piston rod 3 extends out of the cylinder body 1 through the front cover 4. A forward oil inlet / outlet hole 6 and a rear oil inlet / outlet hole 7 are respectively provided at the front and rear ends of the cylinder body 1, forming a double-acting cylinder 8. The action of the double-acting cylinder 8 is controlled by a hydraulic system. An axe 10 for splitting wood 9 is fixed to the front end of the piston rod 3. A push plate 12 is fixed to the bed 11 behind the wood 9, or a push plate 12 is fixed to the front end of the piston rod 3, and an axe 10 (not shown in the diagram) is fixed to the bed 11 opposite the push plate 12. A through hole 13 is provided at the rear end of the rear cover 5, through which the front end of a force-boosting rod 14 extends into the cylinder body 1 to boost force. The rear end of rod 14 protrudes outside the rear cover 5. The rear end of the force-boosting rod 14 receives the thrust from other thrust devices. The double-acting cylinder 8 and the thrust device are respectively fixed to the bed 11 of the wood splitter, or the double-acting cylinder 8 and the thrust device are connected together and then fixed to the bed 11 of the wood splitter. The thrust device refers to the screw thread mechanism 15. The screw thread mechanism 15 includes a connecting bracket 16. A nut 17 is fixed to the tail of the connecting bracket 16. A screw 18 that matches the nut thread is screwed into the nut 17. A force-applying handle 19 that facilitates the rotation of the screw 18 is fixed to the tail end of the screw 18. The front part of the connecting bracket 16 is connected to the double-acting cylinder 8 through the rear cover 5. The front end of the screw 18 abuts against the rear end of the force-boosting rod 14. The front end of the force-boosting rod 14 abuts against the piston rod 3 or piston 2, etc. Figure 1 As shown, or simply extending into the cylinder body 1, the booster rod 14 does not contact the piston rod 3 or piston 2. Figure 2 As shown.

[0024] Example 2

[0025] This structure is a hydraulic transmission device consisting of a double-acting cylinder 8 followed by a single-acting cylinder 20. Figure 4As can be seen, the structure of the double-acting cylinder 6 is the same as that in Embodiment 1. The difference is that the thrust device is a hydraulic transmission device of a single-acting cylinder 20. The hydraulic transmission device of the single-acting cylinder 20 includes a single-acting cylinder body 21, in which a single-acting piston 22 is installed. The front end of the single-acting piston 22 is the piston rod 23 or the booster rod 14 of the single-acting cylinder (in this embodiment, the piston rod 23 and the booster rod 14 of the single-acting cylinder are integrated). The rear end of the single-acting cylinder body 21 has a single-acting inlet / outlet port 24, forming the single-acting cylinder 20, and a hydraulic system for controlling the single-acting cylinder 20. The stroke of the single-acting cylinder 20 is less than that of the double-acting cylinder. The hydraulic system for controlling the double-acting cylinder 8 and the single-acting cylinder 20 includes a hydraulic pump 25, a relief valve 26, and a three-position four-way control valve 27 for controlling the inlet and outlet of hydraulic oil in the cylinder body 1. The three-position four-way control valve 27 is also connected to the single-acting inlet / outlet port 24. The single-acting hydraulic cylinder 20 is connected to the rear cover 5 via a flange 28 located in front of the single-acting cylinder body 21. The piston rod 23 of the single-acting hydraulic cylinder abuts against the tail of the booster rod 14. Figure 4 (Not shown in the text) or the piston rod 23 of a single-acting hydraulic cylinder is integrated with the booster rod 14, as shown in the image. Figure 4 As shown, the hydraulic system controlling the double-acting cylinder 8 and the hydraulic system controlling the single-acting cylinder 20 share a single hydraulic pump 25. The front end of the single-acting cylinder has a vent 29, into which a scale 30, capable of vertical movement, is inserted. The lower end of the scale 30 extends slightly into the single-acting cylinder body 21. A ramp 31 is formed at the front end of the single-acting piston 22. When the single-acting piston 22 moves to the position in front of the single-acting cylinder 20, the ramp 31 lifts the scale 30, indicating that the single-acting piston 22 has reached this position. At the beginning of splitting the wood, the double-acting cylinder 8 and the single-acting cylinder 20 apply force simultaneously, resulting in a combined thrust and a large propulsive force. When the stroke of the single-acting cylinder 20 ends and the wood 9 is split (cracks appear), oil supply to the single-acting cylinder 20 ceases, and the oil output from the hydraulic pump 25 is concentrated on supplying oil to the double-acting cylinder 8. This accelerates the propulsive speed of the double-acting cylinder 8, allowing the wood 9 to split quickly.

[0026] Example 3

[0027] In this structure, when the thrust device connected to the rear end of the double-acting cylinder 8 is a single-acting cylinder 20, compared with embodiment 2, a deep hole 32 is formed at the tail of its piston rod 3. Figure 5As shown, the diameter of the deep hole 32 is larger than the diameter of the front end of the booster rod 14 or the piston rod 23 of the single-acting cylinder that extends into the cylinder body 1. The front end of the booster rod 14 or the piston rod 23 of the single-acting cylinder (in the figure, the booster rod 14 and the piston rod 23 of the single-acting cylinder are made as one piece, and will be referred to as the piston rod 23 of the single-acting cylinder below) can extend into the deep hole 23, and the piston rod 23 of the single-acting cylinder does not contact the piston rod 3. Furthermore, a hydraulically controlled check valve 33 and an M-shaped three-position four-way control valve 34 for controlling the hydraulic oil of the single-acting cylinder 20 entering and exiting the single-acting cylinder body 21 are added to the hydraulic system controlling the double-acting cylinder 8. When splitting wood begins, if the double-acting cylinder 8 can split the wood 9 under the output pressure of the hydraulic pump 25, the splitting operation proceeds smoothly. If the double-acting cylinder 8 cannot split the wood 9 under the output pressure of the hydraulic pump 25, the pressure in the rear chamber of the double-acting cylinder 8 is higher than the output pressure of the hydraulic pump 25 because the diameter of the single-acting piston 22 is larger than the diameter of the piston rod 23 of the single-acting cylinder. As a result, the hydraulic check valve 33 is closed, and all the hydraulic oil output by the hydraulic pump 25 enters the chamber of the single-acting cylinder 20. The piston rod 23 of the single-acting cylinder, which extends into the chamber of the double-acting cylinder 8, forces the pressure inside the double-acting cylinder 8 to rise. At this time, the piston rod 3 of the double-acting cylinder 8 outputs the maximum thrust, causing the wood 9 to be split. If, during the rapid splitting process, a knot is encountered and the resistance increases, the piston rod 23 of the single-acting cylinder can be retracted a certain distance and then re-entered into the cylinder body 1 to increase the hydraulic pressure between the rear cover 5 and the piston 2 inside the cylinder body 1. The output force of the piston rod 3 of the double-acting cylinder 8 will also increase again, that is, the thrust of the piston rod 3 will be increased again until the wood 9 is completely split.

[0028] Of course, the examples given above are merely preferred embodiments of this utility model, and do not limit the scope of implementation of this utility model. All equivalent changes and modifications made within the scope of this application shall still fall within the protection scope of this utility model.

Claims

1. A hydraulic cylinder for a wood splitter with a booster rod at the rear end of a double-acting cylinder, comprising a cylinder body, a piston and a piston rod installed within the cylinder body, a front cover and a rear cover fixed to the front and rear ends of the cylinder body, the piston rod extending out of the cylinder body through the front cover, and inlet / outlet and outlet ports at the front and rear ends of the cylinder body respectively, forming a double-acting cylinder, the action of which is controlled by a hydraulic system, an axe for splitting wood fixed to the front end of the piston rod, and a push plate fixed to the bed behind the wood, or a push plate fixed to the front end of the piston rod, the push plate being fixed to the bed opposite to the bed. The machine is equipped with an axe-like mechanism. Its distinguishing feature is a through hole at the rear end of the rear cover. The front end of a lever extends through this hole into the cylinder body, while the rear end of the lever protrudes outside the rear cover. The rear end of the lever receives thrust from other thrusting devices. The double-acting cylinder and thrusting device are respectively fixed to the bed of the wood splitter, or the double-acting cylinder and thrusting device are connected together and then fixed to the bed of the wood splitter. The thrusting device refers to a screw thread mechanism or a single-acting cylinder. The piston rod of the single-acting cylinder abuts against the tail of the lever, or the piston rod of the single-acting cylinder and the lever are integrated.

2. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder as described in claim 1, characterized in that... The aforementioned lead screw thread mechanism includes a connecting bracket, a nut fixed at the tail of the connecting bracket, a lead screw threaded in the nut that matches the nut thread, a force-applying handle fixed at the tail end of the lead screw to facilitate its rotation, a front part of the connecting bracket connected to a double-acting hydraulic cylinder via a rear cover, and the front end of the lead screw abutting against the rear end of the force-applying rod.

3. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder as described in claim 1, characterized in that... The hydraulic system controlling the double-acting cylinder includes a hydraulic pump, a relief valve, and a three-position four-way control valve for controlling the inflow and outflow of hydraulic oil into and out of the cylinder.

4. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder as described in claim 1, characterized in that... The hydraulic transmission device for the single-acting cylinder includes a single-acting cylinder body, a single-acting piston installed in the single-acting cylinder body, the front end of the single-acting piston being the piston rod or booster rod of the single-acting cylinder, and a single-acting inlet / outlet oil port formed at the rear end of the single-acting cylinder body, thus forming a single-acting cylinder, and a hydraulic system for controlling the single-acting cylinder.

5. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder as described in claim 4, characterized in that... The single-acting cylinder has a vent hole at its front end, and a scale that can move up and down is inserted into the vent hole. The lower end of the scale extends slightly into the single-acting cylinder body, and an inclined surface is formed at the front end of the single-acting piston.

6. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder according to claim 4, characterized in that... The single-acting hydraulic cylinder is connected to the rear cover via a flange located at the front of the single-acting hydraulic cylinder body.

7. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder according to claim 4, characterized in that... The hydraulic system controlling the double-acting and single-acting cylinders includes a hydraulic pump, a relief valve, and a three-position four-way control valve for controlling the inflow and outflow of hydraulic oil into and out of the cylinder body.

8. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder according to claim 4, characterized in that... When the thrust device connected to the rear end of the double-acting cylinder is a single-acting cylinder, a deep hole is made at the tail of its piston rod. The diameter of the deep hole is larger than the diameter of the front end of the booster rod or the piston rod of the single-acting cylinder that extends into the cylinder body. The front end of the booster rod or the piston rod of the single-acting cylinder can extend into the deep hole, and the booster rod or the piston rod of the single-acting cylinder does not contact the piston rod.

9. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting cylinder according to claim 4, characterized in that... The hydraulic system controlling the double-acting cylinder and the hydraulic system controlling the single-acting cylinder share a single hydraulic pump.

10. A hydraulic cylinder for a log splitter with a force-boosting rod at the rear end of a double-acting hydraulic cylinder according to claim 4, characterized in that... The stroke of the single-acting hydraulic cylinder is less than that of the double-acting hydraulic cylinder.

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