Piston and electric hammer

Abstract

A piston, which relates to the technical field of hardware products, comprises a piston cylinder body, a piston kit, a connecting rod and a connecting rod pin. The piston kit is installed in the piston cylinder body. The piston kit includes a rotating assembly and a connecting shaft. The rotating assembly is arranged in the piston cylinder body. The connecting shaft is connected to the rotating assembly. The rotation of the piston cylinder body can drive the rotating assembly and the connecting shaft to rotate relatively. The connecting rod pin is inserted into the connecting rod and the end of the connecting shaft. The connecting rod and the connecting shaft are movably connected through the connecting rod pin. When the cylinder makes a rotational movement, under the action of friction, the piston cylinder body rotates together with the cylinder. That is, under the action of the ball, the bearing base fixedly connected to the piston cylinder body can rotate relative to the bearing middle seat, and the bearing middle seat is fixedly connected to the connecting shaft. When the connecting rod and the connecting shaft are fixed and do not rotate, the piston cylinder body and the bearing base rotate driven by the cylinder, reducing the friction between the cylinder and the piston cylinder body and increasing the service life of the electric hammer. The present invention also provides an electric hammer.

Description

Technical Field

[0001] The present invention relates to the technical field of hardware products, and particularly to a piston and a hammer drill. Background Art

[0002] A hammer drill is an electric rotary hammer drill with a pneumatic hammering mechanism. The hammer drill utilizes the principle of piston movement to compress gas to impact the drill bit. Among them, when the hammer drill is working, the cylinder rotates, and the piston makes a linear reciprocating motion in the cylinder. The gas in the cylinder is compressed by the reciprocating motion of the piston to generate hammering power.

[0003] In the above-mentioned prior art, the piston only makes a linear reciprocating motion in the cylinder, and when the cylinder rotates, the piston does not rotate with the cylinder. This motion mode has the following technical problems: when the piston reciprocates in the cylinder to compress the gas, the rotation of the cylinder while the piston does not rotate increases the friction between the cylinder and the piston, causing wear inside the cylinder, reducing the cylinder sealing performance, resulting in partial pressure leakage, and the impact force of the hammer drill decreases or even does not impact due to insufficient pressure inside the cylinder, thus affecting the working efficiency, increasing the load on the motor, and reducing the service life of the hammer drill.

[0004] In response to the above technical problems, the prior art provides corresponding solutions. For example, the technical solution provided by the Chinese patent application with the application number 201822225639.6 and the invention title of "New Hammer Drill Piston": The piston body is in rolling contact connection with the clutch sleeve through balls. One end of the piston body is connected to the swing shaft through a transmission pin, and a sealing ring is provided at the other end. A groove is provided on the piston body, the balls are arranged in the groove, a fixing member is provided on the groove, the fixing member is fixed on the piston body by bolts, and the inner side surface of the fixing member is an arc surface that matches the balls.

[0005] However, the above prior art has the following problems: Since the balls are in contact connection with the clutch sleeve (cylinder), after the clutch sleeve and the piston rotate relative to each other for a long time, wear will occur inside the clutch sleeve, thus affecting the sealing performance, resulting in pressure leakage, and reducing the service life of the hammer drill. Summary of the Invention

[0006] In view of this, it is necessary to provide a piston that can rotate with the cylinder while making a reciprocating linear motion.

[0007] It is also necessary to provide a hammer drill.

[0008] A piston, comprising a piston cylinder body, a piston kit, a connecting rod and a connecting rod pin. The piston kit is installed inside the piston cylinder body. The piston kit includes a rotating assembly and a connecting shaft. The rotating assembly is arranged inside the piston cylinder body. The connecting shaft is connected to the rotating assembly. The rotation of the piston cylinder body can drive the rotating assembly and the connecting shaft to rotate relative to each other. The connecting rod pin is inserted into the connecting rod and the end of the connecting shaft, and the connecting rod and the connecting shaft are movably connected through the connecting rod pin.

[0009] Preferably, the rotating assembly includes a bearing base, a bearing middle seat, a cage and balls. The outer cylindrical surface of the bearing base is fixedly attached to the inner surface of the piston cylinder body. The bearing middle seat is located between the bearing bases, and both side surfaces of the bearing middle seat are provided with ball grooves. The side surface of the bearing base close to the bearing middle seat is also provided with a ball groove. The cage is located between the bearing middle seat and the bearing base. The balls are installed in the cage, and the surface of the balls is in contact with the ball groove surfaces on the bearing base and the bearing middle seat. The bearing middle seat can rotate relative to the bearing base under the action of the balls.

[0010] Preferably, the connecting shaft passes through the bearing base and is fixedly connected to the bearing middle seat.

[0011] Preferably, the bearing base includes an upper bearing base and a lower bearing base. The upper bearing base is located above the bearing middle seat, and the lower bearing base is located below the bearing middle seat. The lower bottom surface of the lower bearing base is fixedly attached to the inner bottom surface of the piston cylinder body.

[0012] Preferably, a snap ring groove is provided on the inner wall of the piston cylinder body, and the snap ring groove is located above the upper bearing base. A snap ring is also provided in the snap ring groove, and the snap ring can catch the upper bearing base.

[0013] Preferably, both ends of the connecting rod are semi-cylindrical, and are respectively a first connecting end and a second connecting end. Connecting holes are respectively provided on the first connecting end and the second connecting end. The first connecting end is provided with an installation groove in the radial direction, and the installation groove is located at the axial middle position.

[0014] Preferably, a connecting hole is also provided at the end of the connecting shaft, and the end of the connecting shaft is installed in the installation groove. The connecting rod pin is respectively inserted into the connecting hole at the end of the connecting shaft and the connecting hole at the first connecting end, to movably connect the connecting shaft and the connecting rod.

[0015] Preferably, a sealing groove is provided on the outer wall of the piston cylinder body, and the sealing groove is close to the bottom of the piston body.

[0016] Preferably, an axial groove is also provided at the inner bottom of the piston cylinder body.

[0017] A hammer drill, comprising a hammer drill body, an impact component, a cylinder, a cylinder drive mechanism, a piston, a piston drive mechanism and a main drive component. The impact component, the cylinder, the cylinder drive mechanism, the piston, the piston drive mechanism and the main drive component are all arranged inside the hammer drill body. The piston is the aforementioned piston. The main drive component is respectively connected to the cylinder drive mechanism and the piston drive mechanism. The cylinder drive mechanism is connected to the cylinder. The impact component is located at the front end of the cylinder. The piston is installed inside the cylinder, and the second connection end of the piston connecting rod is connected to the piston drive mechanism.

[0018] When the above technical solution is adopted in the present invention, the beneficial effect is as follows: When the piston makes a reciprocating linear motion in this solution, it can rotate together with the cylinder. Among them, when the cylinder makes a rotational motion, under the action of friction, the piston cylinder body rotates together with the cylinder. That is, under the action of the balls, the bearing base fixedly connected to the piston cylinder body can rotate relative to the bearing middle seat, and the bearing middle seat is fixedly connected to the connecting shaft. When the connecting rod and the connecting shaft are fixed and do not rotate, the piston cylinder body and the bearing base rotate under the drive of the cylinder;

[0019] By adding a piston kit inside the piston cylinder body in this solution, the piston can rotate together with the cylinder while making a reciprocating linear motion, reducing the friction between the cylinder and the piston cylinder body, avoiding the leakage of air pressure inside the cylinder, reducing the load of the motor, and increasing the service life of the hammer drill. Description of the Drawings

[0020] Figure 1 It is a schematic structural view of the present invention.

[0021] Figure 2 is Figure 1 a partial sectional view of

[0022] Figure 3 It is an exploded view of the present invention.

[0023] Figure 4 It is a schematic structural view of the connecting rod of the present invention.

[0024] Figure 5 It is a schematic structural view of the hammer drill.

[0025] In the figure: piston cylinder body 1, snap ring groove 11, snap ring 111, sealing groove 12, shaft groove 13, piston kit 2, rotating assembly 21, bearing base 211, upper bearing base 2111, lower bearing base 2112, bearing middle seat 212, ball groove 2121, cage 213, ball 214, connecting shaft 22, connecting rod 3, first connecting end 31, mounting groove 311, second connecting end 32, connecting hole 33, connecting rod pin 4, electric hammer body 5, impact component 6, cylinder 7, cylinder drive mechanism 8, piston drive mechanism 9, main drive part 10. Detailed implementation mode

[0026] Please refer to Figures 1 to 5 , an embodiment of the present invention provides a piston, including a piston cylinder body 1, a piston kit 2 and a connecting rod 3.

[0027] The piston kit 2 is installed inside the piston cylinder body 1. The piston kit 2 includes a rotating assembly 21 and a connecting shaft 22. The rotating assembly 21 is arranged inside the piston cylinder body 1. The connecting shaft 22 is connected to the rotating assembly 21. When the piston cylinder body 1 rotates, it can drive the rotating assembly 21 and the connecting shaft 22 to rotate relative to each other. The connecting rod pin 4 is inserted into the connecting rod 3 and the end of the connecting shaft 22. The connecting rod 3 and the connecting shaft 22 are movably connected through the connecting rod pin 4.

[0028] When the electric hammer is working, the cylinder drive mechanism 8 drives the cylinder 7 to make a rotational motion. At the same time, the piston drive mechanism 9 drives the piston to make a reciprocating linear motion, that is, the reciprocating linear motion of the piston in the cylinder 7 compresses air to form an impact force, and repeatedly hammers the impact component 6. Among them, when the cylinder drive mechanism 8 drives the cylinder 7 to rotate, the piston in the cylinder 7 makes a reciprocating linear motion under the action of the piston drive mechanism 9 and also rotates with the cylinder 7 at the same time, that is, the piston cylinder body 1 is driven to rotate through the frictional force between the inner wall of the cylinder 7 and the outer wall of the piston cylinder body 1, and the frictional force is converted into a usable frictional force.

[0029] Furthermore, the rotating assembly 21 includes a bearing base 211, a bearing middle seat 212, a cage 213 and balls 214. The outer cylindrical surface of the bearing base 211 is fixedly attached to the inner surface of the piston cylinder body 1. The bearing middle seat 212 is located between the bearing bases 211. Ball grooves 2121 are provided on both side surfaces of the bearing middle seat 212. Ball grooves 2121 are also provided on the side surfaces of the bearing bases 211 close to the bearing middle seat 212. The cage 213 is located between the bearing middle seat 212 and the bearing bases 211. The balls 214 are installed in the cage 213, and the surface of the balls 214 is in contact with the groove surfaces of the ball grooves 2121 on the bearing bases 211 and the bearing middle seat 212. The bearing middle seat 212 can rotate relative to the bearing bases 211 under the action of the balls 214.

[0030] When the piston rotates with the cylinder 7, that is, when the piston cylinder body 1 rotates with the cylinder 7, it drives the bearing base 211 fixedly connected to the piston cylinder body 1 to rotate together. Under the action of the balls 214 in the ball groove 2121, the bearing base 211 rotates relative to the bearing middle seat 212. Among them, the cage 213 is used to maintain the distance between the balls 214.

[0031] Furthermore, the connecting shaft 22 passes through the bearing base 211 and is fixedly connected to the bearing middle seat 212. When the electric hammer works, the driving component drives the connecting rod 3, and then the connecting rod 3 drives the connecting shaft 22, and the connecting shaft 22 drives the bearing middle seat 212 and the piston cylinder body 1 to reciprocate in the cylinder 7.

[0032] Furthermore, the bearing base 211 includes an upper bearing base 2111 and a lower bearing base 2112. The upper bearing base 2111 is located above the bearing middle seat 212, and the lower bearing base 2112 is located below the bearing middle seat 212. And the lower bottom surface of the lower bearing base 2112 is fixedly attached to the inner bottom surface of the piston cylinder body 1.

[0033] In this design, the balls 214 are installed in the ball groove 2121 through the upper bearing base 2111, the lower bearing base 2112 and the bearing middle seat 212. Through the rolling of the balls 214, the bearing middle seat 212 can rotate relative to the bearing base 211. Since the upper bearing base 2111 and the lower bearing base 2112 are fixed in the piston cylinder body 1, the bearing base 211, the bearing middle seat 212, the balls 214 and the cage 213 are combined to form a double-sided bearing, and the outer diameter of the bearing middle seat 212 is smaller than the outer diameter of the bearing base 211.

[0034] Furthermore, a snap ring groove 11 is provided on the inner wall of the piston cylinder body 1, and the snap ring groove 11 is located above the upper bearing base 2111. A snap ring 111 is also provided in the snap ring groove 11, and the snap ring 111 can hold the upper bearing base 2111.

[0035] In order to prevent the bearing base 211 from shifting due to rotation and reciprocating motion during the operation of the electric hammer, resulting in the dropping of the balls 214 and the shaking of the bearing central axis, damaging the electric hammer and causing accidents or affecting the impact effect of the electric hammer, the snap ring 111 is used to limit the position of the upper bearing base 2111, so that the inner bottom surface of the piston cylinder body 1 and the snap ring 111 form an installation partition for installing the bearing base 211.

[0036] Furthermore, both ends of the connecting rod 3 are semi-cylindrical, and are respectively a first connection end 31 and a second connection end 32. Connection holes 33 are respectively provided on the first connection end 31 and the second connection end 32. The first connection end 31 is provided with an installation groove 311 in the radial direction, and the installation groove 311 is located at the axial middle position.

[0037] Further, a connection hole 33 is also provided at the end of the connecting shaft 22, and the end of the connecting shaft 22 is installed in the installation groove 311. The connecting rod pins 4 are respectively inserted into the connection holes 33 at the end of the connecting shaft 22 and the first connection end 31, movably connecting the connecting shaft 22 with the connecting rod 3.

[0038] Design the connecting rod 3 to match the connecting shaft 22. When the connecting rod 3 drives the piston to reciprocate, relative rotation also occurs at the connection between the connecting rod 3 and the connecting shaft 22. An installation groove 311 is provided at the first connection end 31 of the connecting rod 3, so that the connection hole 33 at the connecting shaft 22 is aligned with the connection hole 33 at the first connection end 31 of the connecting rod 3, facilitating the installation of the connecting rod 3 pins and enabling rotation at the connection between the connecting rod 3 and the connecting shaft 22.

[0039] Further, a sealing groove 12 is provided on the outer wall of the piston cylinder body 1, and the sealing groove 12 is close to the bottom of the piston body.

[0040] When the piston reciprocates and rotates in the cylinder 7, in order to prevent the air pressure in the cylinder 7 from leaking during the piston movement, a sealing groove 12 is provided at a position near the bottom end of the piston outer wall for installing a sealing ring to reduce the air pressure leakage generated during the piston movement.

[0041] Further, a shaft groove 13 is also provided at the inner bottom of the piston cylinder body 1.

[0042] When installing the connecting shaft 22, the bottom of the connecting shaft 22 can be inserted into the shaft groove 13. In order to prevent one end of the connecting shaft 22 from being too long and affecting the installation during installation, a shaft groove 13 is provided at the inner bottom of the piston cylinder body 1, so that the bottom end of the connecting shaft 22 can be inserted into the shaft groove 13, facilitating the installation of the piston kit 2.

[0043] In an embodiment of the present invention, a hammer drill is further provided, which includes a hammer drill body 5, an impact component 6, a cylinder 7, a cylinder driving mechanism 8, a piston, a piston driving mechanism 9, and a main driving component 10. The impact component 6, the cylinder 7, the cylinder driving mechanism 8, the piston, the piston driving mechanism 9, and the main driving component 10 are all arranged in the hammer drill body 5. The main driving component 10 is respectively connected to the cylinder driving mechanism 8 and the piston driving mechanism 9. The cylinder driving mechanism 8 is connected to the cylinder 7. The impact component 6 is located at the front end of the cylinder 7. The piston is installed in the cylinder 7, and the second connection end 32 of the piston connecting rod 3 is connected to the piston driving mechanism 9. Among them, the piston selected in the embodiment of the present invention is the piston provided in the foregoing embodiment of the invention.

[0044] When the electric hammer is working, the main drive member 10 drives the cylinder drive mechanism 8 and the piston drive mechanism 9. The cylinder drive mechanism 8 drives the cylinder 7 to make a rotational motion, and the piston drive mechanism 9 drives the connecting rod 3 of the piston. Then, the connecting rod 3 drives the piston in the cylinder 7 to make a reciprocating linear motion. Among them, when the cylinder 7 rotates, under the action of friction, the piston cylinder body 1 rotates with the cylinder 7, so that the piston makes a rotational motion while making a reciprocating linear motion;

[0045] Among them, when the piston cylinder body 1 rotates, the piston kit 2 does not rotate, but the bearing base 211 fixedly connected to the piston cylinder body 1 rotates. Under the action of the balls 214 in the ball groove 2121, the bearing base 211 and the bearing middle seat 212 make a relative rotational motion.

[0046] The above-disclosed are only the preferred embodiments of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. Those of ordinary skill in the art can understand all or part of the processes of implementing the above embodiments, and the equivalent changes made according to the claims of the present invention still fall within the scope covered by the invention.

Claims

1. A piston, characterized in that: It includes a piston cylinder body, a piston kit, a connecting rod and a connecting rod pin. The piston kit is installed inside the piston cylinder body. The piston kit includes a rotating assembly and a connecting shaft. The rotating assembly is arranged inside the piston cylinder body. The connecting shaft is connected to the rotating assembly. When the piston cylinder body rotates, it can drive the rotating assembly and the connecting shaft to rotate relative to each other. The connecting rod pin is inserted into the connecting rod and the end of the connecting shaft. The connecting rod and the connecting shaft are movably connected through the connecting rod pin. The rotating assembly includes a bearing base, a bearing middle seat, a cage and balls. The outer cylindrical surface of the bearing base is fixedly attached to the inner surface of the piston cylinder body. The bearing middle seat is located between the bearing bases. Ball grooves are provided on both side surfaces of the bearing middle seat. Ball grooves are also provided on the side surface of the bearing base close to the bearing middle seat. The cage is located between the bearing middle seat and the bearing base. The balls are installed inside the cage. The surface of the balls is in contact with the ball groove surfaces on the bearing base and the bearing middle seat. The bearing middle seat can rotate relative to the bearing base under the action of the balls. A sealing groove is provided on the outer wall of the piston cylinder body, and the sealing groove is close to the bottom of the piston body.

2. The piston according to claim 1, wherein: The connecting shaft passes through the bearing base and is fixedly connected to the bearing middle seat.

3. The piston according to claim 1, wherein: The bearing base includes an upper bearing base and a lower bearing base. The upper bearing base is located above the bearing middle seat. The lower bearing base is located below the bearing middle seat. The bottom surface of the lower bearing base is fixedly attached to the inner bottom surface of the piston cylinder body.

4. The piston according to claim 3, wherein: A snap ring groove is provided on the inner wall of the piston cylinder body, and the snap ring groove is located above the upper bearing base. A snap ring is also provided in the snap ring groove, and the snap ring can hold the upper bearing base.

5. The piston according to claim 1, characterized in that: Both ends of the connecting rod are semi-cylindrical, and are respectively a first connecting end and a second connecting end. Connecting holes are respectively provided on the first connecting end and the second connecting end. The first connecting end is provided with an installation groove in the radial direction, and the installation groove is located at the axial middle position.

6. The piston according to claim 5, characterized in that: A connecting hole is also provided at the end of the connecting shaft, and the end of the connecting shaft is installed in the installation groove. The connecting rod pin is respectively inserted into the connecting hole at the end of the connecting shaft and the connecting hole on the first connecting end, to movably connect the connecting shaft and the connecting rod.

7. The piston according to claim 1, characterized in that: An axial groove is also provided at the inner bottom of the piston cylinder body.

8. An electric hammer, characterized in that: It includes a hammer drill body, an impact component, a cylinder, a cylinder driving mechanism, a piston, a piston driving mechanism and a main driving component. The impact component, the cylinder, the cylinder driving mechanism, the piston, the piston driving mechanism and the main driving component are all arranged inside the hammer drill body. The piston is the piston as described in claim 5. The main driving component is respectively connected to the cylinder driving mechanism and the piston driving mechanism. The cylinder driving mechanism is connected to the cylinder. The impact component is located at the front end of the cylinder. The piston is installed inside the cylinder, and the second connecting end of the connecting rod is connected to the piston driving mechanism.

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