Cylinder fixing structure for electric shovel

Abstract

The utility model discloses a cylinder fixing structure of electric grab, including chuck, front cylinder and gear box, and the chuck is connected in the front of front cylinder through screw, and the gear box is connected in the rear of front cylinder through screw, and the cylinder is provided in the front cylinder, and the cylinder is equipped with the rammer and piston, and the front end locating seat is arranged between the front cylinder and the iron head, and the rear end fixed seat is arranged between the front cylinder and the gear box, and the thermal expansion coefficient of front end locating seat and rear end fixed seat is same or similar with the cylinder, and the rear end face of front end locating seat is equipped with annular locating groove, and the front end of cylinder inserts into annular locating groove, and the locating hole is seted up on the rear end fixed seat, and the rear end fixed seat is sleeved on the outside of the rear end of cylinder through locating hole, and the front and rear ends of cylinder are positioned through setting front end locating seat and rear end fixed seat, so as to improve the stability of cylinder after thermal expansion.

Description

Technical Field

[0001] This utility model relates to an electric pick, and more particularly to a cylinder fixing structure for an electric pick. Background Technology

[0002] An electric pick is a double-insulated handheld power tool powered by a single-phase series-wound motor. It is safe, reliable, efficient, and easy to operate. It is widely used in pipeline laying, machinery installation, water supply and drainage facility construction, interior decoration, port facility construction, and other construction projects. It is suitable for use with picks or other appropriate accessories, such as chisels and shovels, to break, level, excavate, groove, and cut concrete, masonry structures, and asphalt pavements.

[0003] For example, the electric pick disclosed in patent CN210819414U includes: a housing, and a motor, a transmission system, an impact system, and a chuck that extends at least partially out of the housing, the chuck having a hexagonal receiving hole for engaging with a working head; the impact system includes: a cylinder, a connecting rod, a piston, an air cushion, a hammer, and a striking rod, all of which are at least partially disposed within the cylinder, the connecting rod, piston, air cushion, hammer, and striking rod being sequentially connected; the housing includes a straight cylinder for assembling the chuck and impact system, the straight cylinder being connected to the chuck by screws; the cylinder is disposed within the straight cylinder and is tightly fitted and fixed to the inner wall of the straight cylinder; the transmission system is disposed on the side of the motor near the chuck, for transmitting the power output by the motor to the connecting rod of the impact system, the connecting rod driving the piston to reciprocate, the piston reciprocating compressing the air cushion, the air cushion sequentially transmitting the energy of the piston to the hammer and striking rod, thereby driving the working head to reciprocate.

[0004] Because the working principle of an electric hammer is that the internal system reciprocates within a cylinder to generate impact, thereby achieving the function of cutting and blasting. When the internal impact structure reciprocates within the cylinder, the friction of the parts and the compression of air generate high temperatures. The cylinder and the straight cylinder are made of two different materials. The cylinder is generally made of wear-resistant and heat-resistant material. Due to the different thermal expansion systems of the two materials, the straight cylinder will become dimensionally unstable after thermal expansion. A gap will be generated between the straight cylinder and the inner wall of the cylinder, causing the cylinder to fail to fix itself. The cylinder will vibrate within the straight cylinder, thus preventing the internal impact system from operating normally, resulting in reduced impact system performance and performance failure. Utility Model Content

[0005] Based on the above, since the working principle of an electric hammer is that the internal system reciprocates within the cylinder to generate impact, thereby achieving the function of cutting and blasting, the internal impact structure generates high temperatures due to friction of components and air compression during the reciprocating impact motion within the cylinder. The cylinder and the straight cylinder are made of two different materials; the cylinder is generally made of wear-resistant and heat-resistant material. Due to the different thermal expansion systems of the two materials, the straight cylinder becomes dimensionally unstable after thermal expansion, creating a gap between the straight cylinder and the inner wall of the cylinder, causing cylinder fixing failure. The cylinder will vibrate within the straight cylinder, thus preventing the internal impact system from operating normally, resulting in reduced impact system performance and performance failure. Therefore, this utility model provides a cylinder fixing structure for an electric hammer.

[0006] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: A cylinder fixing structure for an electric hammer includes a chuck for mounting the working head, a front cylinder, and a gearbox. The chuck is connected to the front part of the front cylinder by screws, and the gearbox is connected to the rear part of the front cylinder by screws. A cylinder is installed inside the front cylinder, and a reciprocating hammer and piston are installed inside the cylinder. A front positioning seat is provided between the front cylinder and the hammer head, and a rear fixing seat is provided between the front cylinder and the gearbox. The front positioning seat and the rear fixing seat have similar coefficients of thermal expansion to the cylinder. Similar to or similar, the rear end face of the front positioning seat is provided with an annular positioning groove. The front end of the cylinder is inserted into the annular positioning groove. The outer side wall of the front end of the cylinder is in contact with the outer side wall of the annular positioning groove. The cylinder is placed on the inner bottom of the annular positioning groove, which is opposite to the groove opening. The rear end fixing seat is provided with a positioning hole. The rear end fixing seat is fitted onto the outside of the rear end of the cylinder through the positioning hole. The outer side wall of the rear end of the cylinder is in contact with the inner wall of the positioning hole. One of the cylinder and the rear end fixing seat is provided with a limiting part. The other abuts against the limiting part to restrict the cylinder from moving backward.

[0007] A further preferred embodiment of this utility model is as follows: the limiting part is an annular limiting step provided on the outer wall of the cylinder, the rear end fixing seat is sleeved on the outside of the rear end of the cylinder, and the front end face of the rear end fixing seat abuts against the limiting step.

[0008] A further preferred embodiment of this utility model is as follows: the limiting part is an inner ring protrusion on the inner wall of the rear end of the positioning hole, the rear end fixing seat is sleeved on the outside of the rear end of the cylinder, and the rear end face of the cylinder abuts against the inner ring protrusion.

[0009] A further preferred technical solution of this utility model is as follows: an annular first slot is provided on the inner wall of the front end of the front cylinder. The first slot extends forward and penetrates the end face of the front end of the front cylinder to form a first insertion port on the end face of the front end of the front cylinder for the front positioning seat to enter the first slot. The front positioning seat is inserted into the first slot, and the clamp blocks the front side of the first insertion port to limit the front positioning seat.

[0010] A further preferred technical solution of this utility model is as follows: the chuck is provided with a hammer rod that can move back and forth, the rear end face of the front positioning seat is provided with a central through hole, the central through hole is located inside the annular positioning groove, and the rear end of the hammer rod extends from the central through hole to the rear side of the front positioning seat for impact by the hammer.

[0011] A further preferred technical solution of this utility model is as follows: an assembly groove is provided on the front end face of the front positioning seat, the front end of the central through hole is connected to the assembly groove, a front retaining ring and an elastic rubber ring are provided in the assembly groove, the front retaining ring is located in front of the elastic rubber ring, the rear side of the elastic rubber ring abuts against the inner bottom of the side opposite to the groove opening in the assembly groove, the front side of the elastic rubber ring abuts against the rear side of the front retaining ring, the front side of the front retaining ring abuts against the rear side of the chuck, the front retaining ring and the front positioning seat can move back and forth relative to each other, the rear side of the front positioning seat abuts against the inner wall of the end of the first slot away from the first insertion opening, and there is a gap between the front side of the front positioning seat and the chuck for the front positioning seat to move forward.

[0012] A further preferred embodiment of this utility model is as follows: the front positioning seat includes a positioning ring and a rear plate fixed on the rear end of the positioning ring. The positioning ring and the rear plate together form the assembly groove. The annular positioning groove and the central through hole are provided on the rear side of the rear plate.

[0013] A further preferred embodiment of this utility model is as follows: the gearbox body is provided with a crankshaft chamber, and a connecting hole is provided on the front side of the gearbox body to connect the rear end of the front cylinder and the crankshaft chamber. A crankshaft is provided in the crankshaft chamber, and a connecting rod is connected between the crankshaft and the piston. An annular second slot is provided on the inner wall of the connecting hole. The second slot extends forward and penetrates the front end of the gearbox body to form a second insertion port on the front end of the gearbox body for the rear end fixing seat to enter the second slot. The rear end fixing seat is inserted into the second slot, and the rear side of the rear end fixing seat abuts against the inner wall of the second slot at the end away from the second insertion port. The front cylinder blocks the front side of the second insertion port to limit the rear end fixing seat.

[0014] A further preferred embodiment of this invention is that there is a gap between the outer wall of the cylinder and the inner wall of the front cylinder.

[0015] A further preferred embodiment of this utility model is: a plurality of through slots are provided in the communicating hole and located between the crankshaft chamber and the second slot.

[0016] Compared with the prior art, the advantages of this utility model are that the front and rear ends of the cylinder are positioned by designing a front positioning seat and a rear fixing seat. When the cylinder has a high temperature due to friction of internal parts and air compression, the cylinder, the front positioning seat, and the rear fixing seat thermally expand. Since the front positioning seat and the rear fixing seat have the same or similar coefficient of thermal expansion as the cylinder, the front and rear ends of the cylinder are tightly connected to the front positioning seat and the rear fixing seat after thermal expansion, without gaps, thus avoiding cylinder vibration and improving the stability of cylinder assembly. The front and rear ends of the cylinder are fixed in a relatively horizontal form, thereby ensuring the concentric movement of each component in the impact system, reducing component wear and energy consumption during the reciprocating motion of the impact structure, resulting in a longer service life and higher energy transfer efficiency. Attached Figure Description

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will understand that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be construed as limiting the scope of the present invention. Furthermore, unless specifically indicated, the drawings are only schematic representations of the composition or structure of the described objects and may contain exaggerated depictions, and the drawings are not necessarily drawn to scale.

[0018] Figure 1 This is a half-section diagram of an electric pick. Figure 2 for Figure 1 Enlarged view of a portion at point A; Figure 3 for Figure 1 A magnified view of section B; Figure 4 A cross-sectional view showing the connection between the front positioning seat, the cylinder, and the rear fixing seat when the limiting part is a limiting step; Figure 5 This is a cross-sectional diagram showing the connection between the front positioning seat, the cylinder, and the rear fixing seat when the limiting part is an inner ring convex edge.

[0019] In the diagram: 1. Chuck; 2. Front cylinder; 3. Crankshaft; 4. Motor; 5. Crankshaft chamber; 6. Connecting rod; 7. Gearbox; 8. Piston; 9. Cylinder; 10. Hammer; 11. Hammer rod; 12. Front positioning seat; 13. First slot; 14. Annular positioning groove; 15. Central through hole; 16. Elastic rubber ring; 17. Assembly groove; 18. Front retaining ring; 19. Connecting hole; 20. Second slot; 21. Rear end fixing seat; 22. Limiting step; 23. Rear end plate; 24. Positioning ring; 25. Positioning hole; 26. Inner ring protrusion. Detailed Implementation

[0020] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0021] It should be noted that similar labels in the following figures indicate similar items; therefore, once an item is defined in one figure, it may not be further defined and explained in subsequent figures.

[0022] Figures 1-5 As shown, the cylinder fixing structure of the electric hammer includes a chuck 1 for mounting the working head, a front cylinder 2, and a gearbox 7. The chuck 1 is connected to the front part of the front cylinder 2 by screws, and the gearbox 7 is connected to the rear part of the front cylinder 2 by screws. A cylinder 9 is installed inside the front cylinder 2, and a reciprocating hammer 10 and a piston 8 are installed inside the cylinder 9. A front positioning seat 12 is provided between the front cylinder 2 and the hammer head, and a rear fixing seat 21 is provided between the front cylinder 2 and the gearbox 7. The front positioning seat 12 and the rear fixing seat 21 have the same or similar coefficient of thermal expansion as the cylinder 9. An annular positioning groove is provided on the rear end face of the front positioning seat 12. 14. The front end of the cylinder 9 is inserted into the annular positioning groove 14. The outer wall of the front end of the cylinder 9 is in contact with the outer wall of the annular positioning groove 14, and the cylinder 9 is pressed against the inner bottom of the annular positioning groove 14 opposite to the groove opening to position the front end of the cylinder 9. The rear end fixing seat 21 is provided with a positioning hole 25. The rear end fixing seat 21 is fitted onto the outside of the rear end of the cylinder 9 through the positioning hole 25. The outer wall of the rear end of the cylinder 9 is in contact with the inner wall of the positioning hole 25. One of the cylinder 9 and the rear end fixing seat 21 is provided with a limiting part, and the other abuts against the limiting part to restrict the cylinder 9 from moving backward, so as to position the rear end of the cylinder 9.

[0023] This patent designs a front positioning seat 12 and a rear fixing seat 21 to position the front and rear ends of the cylinder 9. When the cylinder 9 reaches a high temperature due to friction of internal parts and air compression, the cylinder 9, the front positioning seat 12, and the rear fixing seat 21 thermally expand. Since the front positioning seat 12 and the rear fixing seat 21 have the same or similar coefficient of thermal expansion as the cylinder 9, the front and rear ends of the cylinder 9 are tightly connected to the front positioning seat 12 and the rear fixing seat 21 after thermal expansion, without any gaps. This prevents the cylinder 9 from shaking, improves the stability of the cylinder 9 assembly, and fixes the front and rear ends of the cylinder 9 in a relatively horizontal manner. This ensures the concentric movement of all components in the impact system, reduces wear and energy consumption of components during the reciprocating motion of the impact structure, extends the service life, and increases energy transfer efficiency.

[0024] Figure 4As shown, the aforementioned limiting part can be an annular limiting step 22 provided on the outer wall of the cylinder 9. The rear end fixing seat 21 is sleeved on the outside of the rear end of the cylinder 9, and the front end face of the rear end fixing seat 21 abuts against the limiting step 22. By the outer wall of the rear end of the cylinder 9 fitting with the inner wall of the positioning hole 25, it is ensured that the rear end fixing seat 21 and the cylinder 9 are concentric. The front end face of the rear end fixing seat 21 abuts against the limiting step 22 to restrict the cylinder 9 from moving backward, so as to avoid the cylinder 9 moving backward and causing chaos in the inlet and outlet of internal and external air when the internal air of the cylinder 9 is compressed.

[0025] Figure 5 As shown, in another embodiment, the limiting part is an inner ring protrusion 26 protruding on the inner wall of the rear end of the positioning hole 25. The rear end fixing seat 21 is sleeved on the outside of the rear end of the cylinder 9, and the rear end face of the cylinder 9 abuts against the inner ring protrusion 26. By the outer side wall of the rear end of the cylinder 9 fitting with the inner wall of the positioning hole 25, it is ensured that the rear end fixing seat 21 and the cylinder 9 are concentric. The rear end face of the cylinder 9 abuts against the inner ring protrusion 26 to restrict the rearward movement of the cylinder 9, so as to avoid the rearward movement of the cylinder 9 causing chaos in the inlet and outlet of the internal and external air when the internal air of the cylinder 9 is compressed.

[0026] Figure 1 , Figure 3 As shown, the gearbox 7 has a crankshaft chamber 5 inside. The front side of the gearbox 7 has a connecting hole 18 that connects the rear end of the front cylinder 2 and the crankshaft chamber 5. The crankshaft chamber 5 has a crankshaft 3 inside. A connecting rod 6 connects the crankshaft 3 and the piston 8. A second slot 20 is provided on the inner wall of the connecting hole 18. The second slot 20 extends forward and passes through the front end of the gearbox 7 to form a second insertion port on the front end of the gearbox 7 for the rear end fixing seat 21 to enter the second slot 20. The rear end fixing seat 21 is inserted into the second slot 20. The rear side of the rear end fixing seat 21 abuts against the inner wall of the second slot 20 at the end away from the second insertion port. The front cylinder 2 blocks the front side of the second insertion port to limit the rear end fixing seat 21 and fix the rear end fixing seat 21 between the front cylinder 2 and the gearbox 7.

[0027] The crankshaft 3 is connected to the motor 4 for transmission. The motor 4 drives the crankshaft 3 to rotate and drives the piston 8 to reciprocate in the cylinder 9 through the connecting rod 6. This structure is a conventional technical means in the electric pick, and can be referenced in patent CN203449286U.

[0028] Several through slots are provided inside the connecting hole 18 and between the crankshaft chamber 5 and the second slot 20.

[0029] Figure 2As shown, the front cylinder 2 has an annular first slot 13 on its inner wall at the front end. The first slot 13 extends forward and penetrates the end face of the front end of the front cylinder 2 to form a first insertion port on the end face of the front end of the front cylinder 2 for the front positioning seat 12 to enter the first slot 13. The front positioning seat 12 is inserted into the first slot 13. The chuck 1 blocks the front side of the first insertion port to limit the front positioning seat 12, and the front positioning seat 12 is installed between the chuck 1 and the front cylinder 2.

[0030] The chuck 1 is equipped with a hammer rod 11 that can move back and forth. The rear end of the front positioning seat 12 is provided with a central through hole 15, which is located inside the annular positioning groove 14. The rear end of the hammer rod 11 extends from the central through hole 15 to the rear side of the front positioning seat 12 for impact by the hammer 10.

[0031] A mounting groove 17 is provided on the front end face of the front positioning seat 12. The front end of the central through hole 15 is connected to the mounting groove 17. A front retaining ring 18 and an elastic rubber ring 16 are provided in the mounting groove 17. The front retaining ring 18 is located in front of the elastic rubber ring 16. The rear side of the elastic rubber ring 16 abuts against the inner bottom of the mounting groove 17 on the side opposite to the groove opening. The front side of the elastic rubber ring 16 abuts against the rear side of the front retaining ring 18. The front side of the front retaining ring 18 abuts against the rear side of the chuck 1. The front retaining ring 18 and the front positioning seat 12 can move back and forth relative to each other. The rear side of the front positioning seat 12 abuts against the inner wall of the first slot 13 away from the first insertion opening. There is a gap between the front side of the front positioning seat 12 and the chuck 1 for the front positioning seat 12 to move forward.

[0032] When the hammer 10 strikes the hammer rod 11 forward, the hammer 10 impacts the front positioning seat 12. The front positioning seat 12 moves forward due to the impact of the hammer 10 and squeezes the elastic rubber ring 16. The elastic rubber ring 16 is squeezed and deforms elastically, absorbing part of the kinetic energy, thereby buffering the impact of the hammer 10 on the front positioning seat 12.

[0033] The front positioning seat 12 includes a positioning ring 24 and a rear plate 23 fixed to the rear end of the positioning ring 24. The positioning ring 24 and the rear plate 23 enclose each other to form an assembly groove 17. The annular positioning groove 14 and the central through hole 15 are provided on the rear side of the rear plate 23.

[0034] The outer wall of cylinder 9 can be configured to have a gap with the inner wall of front cylinder 2, so that the two do not form direct contact.

[0035] Cylinder 9, front positioning seat 12 and rear fixing seat 21 are made of wear-resistant and high-temperature resistant materials.

[0036] The cylinder fixing structure of the electric pick provided by this utility model has been described above. Specific examples have been used to illustrate the principle and implementation of this utility model. The descriptions of the embodiments above are only for the purpose of helping to understand this utility model and its core ideas. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principle of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A cylinder fixing structure for an electric hammer, comprising a chuck for mounting a working head, a front cylinder, and a gearbox, wherein the chuck is connected to the front part of the front cylinder by screws, the gearbox is connected to the rear part of the front cylinder by screws, a cylinder is disposed inside the front cylinder, and a reciprocating hammer and a piston are disposed inside the cylinder, characterized in that, A front-end positioning seat is provided between the front cylinder and the iron head, and a rear-end fixing seat is provided between the front cylinder and the gearbox body. The front-end positioning seat and the rear-end fixing seat have the same or similar coefficient of thermal expansion as the cylinder. An annular positioning groove is provided on the rear end face of the front-end positioning seat. The front end of the cylinder is inserted into the annular positioning groove. The outer side wall of the front end of the cylinder fits against the outer side wall of the annular positioning groove, and the cylinder rests on the inner bottom of the annular positioning groove opposite to the groove opening. A positioning hole is provided on the rear-end fixing seat. The rear-end fixing seat is fitted onto the outside of the rear end of the cylinder through the positioning hole. The outer side wall of the rear end of the cylinder fits against the inner wall of the positioning hole. One of the cylinder and the rear-end fixing seat is provided with a limiting part, and the other abuts against the limiting part to restrict the cylinder from moving backward.

2. The cylinder fixing structure of the electric pick according to claim 1, characterized in that, The limiting part is an annular limiting step provided on the outer wall of the cylinder. The rear end fixing seat is sleeved on the outside of the rear end of the cylinder, and the front end face of the rear end fixing seat abuts against the limiting step.

3. The cylinder fixing structure of the electric pick according to claim 1, characterized in that, The limiting part is an inner ring protrusion on the inner wall of the rear end of the positioning hole. The rear end fixing seat is sleeved on the outside of the rear end of the cylinder, and the rear end face of the cylinder abuts against the inner ring protrusion.

4. The cylinder fixing structure of the electric pick according to claim 1, characterized in that, The front cylinder has an annular first slot on its inner wall at the front end. The first slot extends forward and penetrates the end face of the front end of the front cylinder to form a first insertion port on the end face of the front end of the front cylinder for the front positioning seat to enter the first slot. The front positioning seat is inserted into the first slot, and the clamp blocks the front side of the first insertion port to limit the front positioning seat.

5. The cylinder fixing structure of the electric pick according to claim 4, characterized in that, The chuck is equipped with a hammer rod that can move back and forth. The rear end face of the front positioning seat is provided with a central through hole, which is located inside the annular positioning groove. The rear end of the hammer rod extends from the central through hole to the rear side of the front positioning seat for impact by the hammer.

6. The cylinder fixing structure of the electric pick as described in claim 5, characterized in that, The front end face of the front positioning seat is provided with an assembly groove. The front end of the central through hole is connected to the assembly groove. A front retaining ring and an elastic rubber ring are provided in the assembly groove. The front retaining ring is located in front of the elastic rubber ring. The rear side of the elastic rubber ring abuts against the inner bottom of the side of the assembly groove opposite to the groove opening. The front side of the elastic rubber ring abuts against the rear side of the front retaining ring. The front side of the front retaining ring abuts against the rear side of the chuck. The front retaining ring and the front positioning seat can move back and forth relative to each other. The rear side of the front positioning seat abuts against the inner wall of the end of the first slot away from the first insertion opening. There is a gap between the front side of the front positioning seat and the chuck for the front positioning seat to move forward.

7. The cylinder fixing structure of the electric pick according to claim 6, characterized in that, The front-end positioning seat includes a positioning ring and a rear-end plate fixed to the rear end of the positioning ring. The positioning ring and the rear-end plate enclose each other to form the assembly groove. The annular positioning groove and the central through hole are provided on the rear side of the rear-end plate.

8. The cylinder fixing structure of the electric pick according to claim 1, characterized in that, The gearbox contains a crankshaft chamber. A connecting hole is provided on the front side of the gearbox to connect the rear end of the front cylinder and the crankshaft chamber. A crankshaft is provided in the crankshaft chamber. A connecting rod is connected between the crankshaft and the piston. An annular second slot is provided on the inner wall of the connecting hole. The second slot extends forward and penetrates the front end of the gearbox to form a second insertion port on the front end of the gearbox for the rear end fixing seat to enter the second slot. The rear end fixing seat is inserted into the second slot. The rear side of the rear end fixing seat abuts against the inner wall of the second slot at the end away from the second insertion port. The front cylinder blocks the front side of the second insertion port to limit the rear end fixing seat.

9. The cylinder fixing structure of the electric pick according to claim 1, characterized in that, There is a gap between the outer wall of the cylinder and the inner wall of the front cylinder.

10. The cylinder fixing structure of the electric pick according to claim 8, characterized in that, Several through slots are provided inside the connecting hole and between the crankshaft chamber and the second slot.

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