Recoil simulation device of toy gun
By designing a recoil simulation device for toy guns, using the cooperation of the drive assembly and connecting rod assembly to simulate the recoil during fireworks, the problem that existing toy guns cannot effectively simulate recoil is solved, and the user's shooting sense and experience satisfaction are improved.
Patent Information
- Application Number
- CN202421934043.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-09
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-08-09
AI Technical Summary
The toy guns used to simulate shooting on existing amusement machines cannot effectively simulate the recoil generated when the gun is fired during the game, resulting in insufficient shooting feeling and low user experience that users feel in the game.
A recoil simulation device for a toy gun is designed, including a housing, a drive assembly and a connecting rod assembly. By contacting and pressing the linkage lever by the output end of the drive assembly, the linkage lever drives the follower to rotate, and the abutment part of the follower hits the rear cover, thereby simulating the recoil force when the firearm is fired.
The device can simulate the recoil during the firearm during the game, enhance the user's sense of shooting, and improve user experience satisfaction.
Smart Images

Figure CN222912515U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of amusement equipment, and more specifically, to a recoil simulation device for a toy gun. Background Art
[0002] With the improvement of people's living standards, various entertainment activities and amusement equipment have gradually become a hard demand. Among them, shooting simulation arcade machines are more widely welcomed.
[0003] Most of the toy guns used on existing arcade machines are only simulated in appearance and only have the appearance of a gun. When the trigger is pulled during the game, the toy gun can only have some display effects on the screen, and there are no other feedback actions for the toy gun itself, and it is impossible to simulate the recoil generated when the firearm is fired so that the user can feel the impact of the recoil during the game. As a simulated toy gun, a more realistic shooting experience can enhance the user's shooting feeling during the game and the satisfaction of the user experience.
[0004] Regarding the above technical means, there are defects of insufficient game shooting feeling and low user experience satisfaction. Utility Model Content
[0005] The embodiment of this application provides a recoil simulation device for a toy gun, which can enhance the user's shooting feeling during the game and the satisfaction of the user experience.
[0006] The recoil simulation device for a toy gun provided by this application adopts the following technical solutions:
[0007] A recoil simulation device for a toy gun, comprising:
[0008] A housing, the housing includes a rear cover, the rear cover is located at one end of the housing and is rotationally engaged with the housing;
[0009] A driving component, arranged inside the housing, the driving component is used to connect with the trigger;
[0010] A connecting rod component, arranged inside the housing, the connecting rod component is located on one side of the output end of the driving component, the connecting rod component includes a linkage rod and a follower, the linkage rod and the follower are rotationally engaged, and one end of the linkage rod not connected to the follower is arranged on the stroke path of the output end of the driving component; the follower is provided with an abutting portion contacting the rear cover, and the output end of the driving component contacts and presses the linkage rod so that the linkage rod moves towards the rear cover, and the linkage rod drives the follower to rotate so that the abutting portion impacts the rear cover.
[0011] Optionally, a connecting plate is provided at one end of the linkage rod close to the follower, and a first rotating shaft is provided at one end of the follower close to the linkage rod. The first rotating shaft penetrates through the connecting plate and is rotatably connected to the connecting plate. The first rotating shaft is arranged on the movement track of the linkage rod.
[0012] Optionally, it further includes a sleeve arranged on the outer peripheral wall of the linkage rod, and a convex ring is arranged at one end of the inner wall of the sleeve close to the driving component;
[0013] The linkage rod is provided with a first mounting ring, a second mounting ring and a positioning rod. The linkage rod penetrates through the first mounting ring and the second mounting ring. An elastic member is arranged between the first mounting ring and the second mounting ring. The second mounting ring is slidably connected to the sleeve, and the convex ring contacts and presses against the first mounting ring; the positioning rod is located at one end of the sleeve close to the rear cover, and the positioning rod penetrates through the linkage rod and is arranged on one side of the second mounting ring to press against the second mounting ring to compress the elastic member.
[0014] Optionally, it further includes an abutting block arranged on the side of the follower away from the linkage rod. The abutting block is located on the movement track of the connecting plate and / or the follower, and the abutting block is used to limit the movement range of the connecting plate and / or the follower.
[0015] Optionally, the connecting rod assembly further includes a second rotating shaft. One end of the second rotating shaft is fixed to the housing, and the other end of the second rotating shaft penetrates through one end of the follower away from the linkage rod and is rotatably connected to the follower.
[0016] Optionally, the abutting portion is located between the first rotating shaft and the second rotating shaft, and an impact block integrally formed with the abutting portion is arranged on the abutting portion. The impact block is used to increase the contact area between the abutting portion and the rear cover.
[0017] Optionally, the rear cover is provided with a slider and a third rotating shaft. The slider is fixedly connected to the rear cover. One end of the third rotating shaft passing through the slider is arranged on the housing, and the slider drives the rear cover to be rotatably connected to the housing.
[0018] Optionally, a limiting hole is arranged at one end of the slider away from the third rotating shaft, and a limiting rod is arranged on the housing. The limiting rod penetrates through the limiting hole to limit the rotation angle of the slider.
[0019] Optionally, a fixed wheel is arranged on the slider. The fixed wheel is fixedly connected to the slider and is located between the third rotating shaft and the limiting rod. The fixed wheel contacts and is slidably connected to the impact block.
[0020] Optionally, it further includes a mounting plate which is fixedly connected to the housing and is disposed between the housing and the follower to reduce the frictional damage of the follower to the inner wall of the housing.
[0021] As can be seen from the above technical solutions, the embodiments of the present application have the following advantages:
[0022] Pull the trigger, the driving assembly is started by the trigger. The output end of the driving assembly contacts and presses one end of the linkage rod, so that the linkage rod moves towards the direction of the rear cover. The linkage rod drives the follower to rotate, so that the abutting portion of the follower impacts the rear cover, thereby simulating the recoil generated when a firearm is fired, enabling the user to feel the impact of the recoil during the game, enhancing the shooting feeling during the game and improving the user experience satisfaction. Description of the Drawings
[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings.
[0024] Figure 1 It is a schematic diagram of the overall structure of a recoil simulation device for a toy gun disclosed in an embodiment of the present application;
[0025] Figure 2 It is a schematic diagram of the internal structure of a recoil simulation device for a toy gun disclosed in an embodiment of the present application;
[0026] Figure 3 It is a schematic diagram of the structure of a recoil simulation device for a toy gun disclosed in an embodiment of the present application from another perspective;
[0027] Figure 4 It is a schematic diagram of the structure of a recoil simulation device for a toy gun disclosed in an embodiment of the present application highlighting the rear cover;
[0028] Figure 5 It is a state diagram of a recoil simulation device for a toy gun disclosed in an embodiment of the present application highlighting the state where the shoulder presses the rear cover.
[0029] Description of the Reference Numerals:
[0030] 1. Outer shell; 11. Rear cover; 12. Slide block; 121. Limit hole; 122. Fixed wheel; 13. Third rotating shaft; 14. Limit rod; 2. Driving assembly; 3. Linkage assembly; 31. Sleeve; 32. Link rod; 321. Connecting plate; 33. Follow-up part; 331. Contact part; 332. Impact block; 333. First rotating shaft; 34. First mounting ring; 35. Second mounting ring; 36. Positioning rod; 37. Second rotating shaft; 4. Contact block; 5. Mounting plate. Detailed implementation manners
[0031] The following further elaborates on this application in conjunction with the attached drawings.
[0032] The embodiment of this application provides a recoil simulation device for a toy gun.
[0033] To enable those in the technical field to better understand the solution of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this invention. Obviously, the described embodiments are only a part of the embodiments of this invention, rather than all of them. Based on the embodiments of this invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this invention. Additionally, the technical solutions between various embodiments can be combined with each other, but it must be based on the premise that those of ordinary skill in the art can implement them. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.
[0034] The terms "first", "second", "third", "fourth", etc. in the specification and claims of this invention and the above-mentioned accompanying drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described here can be implemented in an order other than that illustrated or described here. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those clearly listed steps or units, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or devices.
[0035] Most of the toy guns used on existing amusement machines are mostly simulated in appearance, only having the appearance of a firearm. When pulling the trigger during the game, the toy gun can only have some presentation effects on the screen, and there are no other feedback actions for the toy gun itself, and it is unable to simulate the recoil generated when the firearm is fired to enable the user to feel the impact of the recoil during the game. To solve the above technical problems, please refer to Figure 1 andFigure 2 This is an embodiment of the recoil device of the toy gun in the embodiments of the present application, including: a housing 1, a driving component 2 and a connecting rod component 3. The driving component 2 and the connecting rod component 3 are both arranged in the housing 1. The driving component 2 is used to connect with the trigger. The connecting rod component 3 is located on one side of the output end of the driving component 2. When the trigger is pulled, the driving component 2 is triggered by the trigger to start, and the output end of the driving component 2 moves towards the connecting rod component 3.
[0036] Please refer to Figure 2 and Figure 4 , the housing 1 includes a rear cover 11. The rear cover 11 is located at one end of the housing 1 and is rotationally matched with the housing 1. The driving component 2 drives the connecting rod component 3 to impact the rear cover 11, thereby simulating the recoil generated when a firearm is fired. The rear cover 11 is used to contact the user's shoulder. An anti-slip layer is provided on the outer peripheral wall of the rear cover 11. The anti-slip layer enhances the friction between the rear cover 11 and the user's shoulder area, thereby alleviating the sliding between the rear cover 11 and the shoulder during the game. In this embodiment, the anti-slip layer is made of rubber material and has a certain buffering effect. When the driving component 2 drives the connecting rod component 3 to impact the rear cover 11, the anti-slip layer can also buffer the impact force and reduce the force received by the user's shoulder.
[0037] Please refer to Figure 2 and Figure 3 , the connecting rod component 3 includes a linkage rod 32 and a follower 33. The linkage rod 32 and the follower 33 are rotationally matched. One end of the linkage rod 32 that is not connected to the follower 33 is arranged on the stroke path of the output end of the driving component 2; the follower 33 is provided with an abutting portion 331 that contacts the rear cover 11. The output end of the driving component 2 contacts and presses the linkage rod 32, so that the linkage rod 32 moves towards the rear cover 11. The linkage rod 32 drives the follower 33 to rotate so that the abutting portion 331 impacts the rear cover 11. That is, when the trigger is pulled, the driving component 2 is triggered by the trigger to start. The output end of the driving component 2 contacts and presses one end of the linkage rod 32, so that the linkage rod 32 moves towards the rear cover 11. The linkage rod 32 drives the follower 33 to rotate, so that the abutting portion 331 of the follower 33 impacts the rear cover 11, thereby simulating the recoil generated when a firearm is fired, enabling the user to feel the impact of the recoil during the game, so as to enhance the shooting feeling during the game and improve the user experience satisfaction.
[0038] Specifically, the linkage rod 32 is horizontally arranged, and the follower 33 is vertically arranged. Under the action of the driving component 2, the linkage rod 32 moves along its length direction. A connecting plate 321 is arranged at one end of the linkage rod 32 close to the follower 33, and the length direction of the connecting plate 321 is the same as that of the linkage rod 32. The first rotating shaft 333 is arranged on the movement track of the linkage rod 32. One end of the follower 33 close to the linkage rod 32 is provided with the first rotating shaft 333. The first rotating shaft 333 penetrates through the connecting plate 321 and is rotatably connected to the connecting plate 321. The driving component 2 contacts and presses against the linkage rod 32, and the linkage rod 32 drives the connecting plate 321 to move synchronously. Under the action of the first rotating shaft 333, the linkage rod 32 drives one end of the follower 33 to rotate so that the abutting portion 331 impacts the rear cover 11.
[0039] In this embodiment, the abutting portion 331 is arranged at the middle position of the follower 33, and the length direction of the abutting portion 331 is parallel to that of the linkage rod 32. The link assembly 3 further includes a second rotating shaft 37. The abutting portion 331 is located between the first rotating shaft 333 and the second rotating shaft 37. One end of the second rotating shaft 37 is fixed to the housing 1, and the other end of the second rotating shaft 37 penetrates through one end portion of the follower 33 far from the linkage rod 32 and is rotatably connected to the follower 33. The follower 33 is rotatably mounted on the housing 1 through the first rotating shaft 333 and the second rotating shaft 37. Under the action of the force of the linkage rod 32, the follower 33 drives one end of the follower 33 connected to the first rotating shaft 333 to move towards the rear cover 11. Taking the second rotating shaft 37 as the rotation point, the follower 33 drives the abutting portion 331 to impact the rear cover 11.
[0040] Furthermore, the abutting portion 331 is provided with an impact block 332. The impact block 332 is integrally formed with the abutting portion 331. The impact block 332 is arranged at the end of the abutting portion 331 in contact with the rear cover 11. The impact block 332 is used to increase the contact area between the abutting portion 331 and the rear cover 11 to ensure that the abutting portion 331 can impact the rear cover 11.
[0041] In order to relieve the frictional damage of the follower 33 to the inside of the housing 1, the recoil simulation device is further provided with a mounting plate 5. The mounting plate 5 is fixedly connected to the housing 1. The mounting plate 5 is arranged between the housing 1 and the follower 33 to reduce the frictional damage of the follower 33 to the inner wall of the housing 1 and extend the service life of the housing 1.
[0042] The link assembly 3 further includes an abutting block 4 arranged on the side of the follower 33 far from the linkage rod 32. The abutting block 4 is fixedly connected to the inside of the housing 1. The abutting block 4 is located on the movement track of the connecting plate 321 and / or the follower 33. The abutting block 4 is used to limit the movement range of the connecting plate 321 and / or the follower 33, thereby limiting the movement distance of the linkage rod 32.
[0043] A sleeve 31 is sleeved on the outer peripheral wall of the linkage rod 32, and a convex ring is arranged at one end of the inner wall of the sleeve 31 close to the driving assembly 2; the linkage rod 32 is provided with a first mounting ring 34, a second mounting ring 35 and a positioning rod 36. The first mounting ring 34 is arranged at one end of the linkage rod 32 close to the driving assembly 2, and the second mounting ring 35 is arranged at one end of the linkage rod 32 close to the rear cover 11. The linkage rod 32 passes through the first mounting ring 34 and the second mounting ring 35. The first mounting ring 34 contacts and presses against the convex ring, and the second mounting ring 35 is slidably connected with the sleeve 31. The positioning rod 36 is located at one end of the sleeve 31 close to the rear cover 11. The positioning rod 36 passes through the linkage rod 32 and is arranged on one side of the second mounting ring 35 to press against the second mounting ring 35. An elastic member is arranged between the first mounting ring 34 and the second mounting ring 35. When the linkage rod 32 resets towards the driving assembly 2, the positioning rod 36 presses against the second mounting ring 35 to be slidably connected with the inner wall of the sleeve 31. The first mounting ring 34 contacts and presses against the convex ring so that the position of the first mounting ring 34 remains unchanged. The second mounting ring 35 moves towards the driving assembly 2 to gradually compress the elastic member. The distance between the end of the linkage rod 32 close to the driving assembly 2 and the driving assembly 2 becomes smaller to ensure that the end of the linkage rod 32 close to the driving assembly 2 is within the movement stroke of the output end of the driving assembly 2.
[0044] Further, the housing 1 is provided with a convex platform, and the convex platform is located at the end of the sleeve 31 close to the rear cover 11. The convex platform is used to limit the sliding position of the second mounting ring 35 to prevent the second mounting ring 35 from detaching from the sleeve 31.
[0045] Please refer to Figure 3 and Figure 4 , the rear cover 11 is provided with a slider 12 and a third rotating shaft 13. The slider 12 is arranged on the end face of the rear cover 11 facing the driving assembly 2, and the slider 12 is fixedly connected with the rear cover 11. One end of the third rotating shaft 13 passing through the slider 12 is arranged on the housing 1, and the slider 12 drives the rear cover 11 to be rotatably connected with the housing 1. In this embodiment, there is a gap between the rear cover 11 and the housing 1. The third rotating shaft 13 is located at the upper end of the slider 12, and the rear cover 11 rotates around the third rotating shaft 13. When receiving the acting force of the abutting portion 331, the rear cover 11 rotates around the third rotating shaft 13. The gap between the lower end of the rear cover 11 and the housing 1 increases, and the gap between the upper end of the rear cover 11 and the housing 1 decreases.
[0046] Further, in order to limit the rotation angle of the rear cover 11, a limiting hole 121 is provided at one end of the slider 12 away from the third rotating shaft 13, that is, the limiting hole 121 is provided at the lower end of the slider 12, and the limiting hole 121 is an oval hole. The outer shell 1 is provided with a limiting rod 14, and the limiting rod 14 passes through the limiting hole 121 to limit the rotation angle of the slider 12. When the user's shoulder presses against the rear cover 11, the limiting rod 14 is located at the rightmost end of the limiting hole 121. At this time, the distance between the lower end of the rear cover 11 and the outer shell 1 becomes smaller, and the distance between the upper end of the rear cover 11 and the outer shell 1 increases; when the user's shoulder disengages from the rear cover 11, the limiting rod 14 is located at the leftmost end of the limiting hole 121. At this time, the distance between the lower end of the rear cover 11 and the outer shell 1 becomes larger, and the distance between the upper end of the rear cover 11 and the outer shell 1 becomes smaller.
[0047] The slider 12 is provided with a fixed wheel 122. The fixed wheel 122 is fixedly connected to the slider 12 and is located between the third rotating shaft 13 and the limiting rod 14, and the fixed wheel 122 is closer to the limiting rod 14. The fixed wheel 122 is in contact with and slidably connected to the impact block 332. When the user's shoulder presses against the rear cover 11, the limiting rod 14 is located at the rightmost end of the limiting hole 121. At this time, the distance between the lower end of the rear cover 11 and the outer shell 1 becomes smaller, and the distance between the fixed wheel 122 and the impact block 332 decreases accordingly, so that the impact block 332 slides along the outer peripheral wall of the fixed wheel 122 and abuts. The fixed wheel 122 exerts a driving force on the impact block 332 to drive the follower 33 to rotate around the second rotating shaft 37, so that the follower 33 drives the linkage rod 32 to move in the direction of the driving assembly 2, ensuring that the end of the follower 33 close to the driving assembly 2 is within the movement stroke of the output end of the driving assembly 2.
[0048] Please refer to Figure 3 and Figure 5 When using the toy gun with this recoil simulation device, first ensure that the user's shoulder presses against the rear cover 11, and ensure that the end of the follower 33 close to the driving assembly 2 is within the movement stroke of the output end of the driving assembly 2; then pull the trigger, trigger the driving assembly 2 to start through the trigger, the output end of the driving assembly 2 contacts and presses one end of the linkage rod 32, so that the linkage rod 32 moves in the direction of the rear cover 11, and the linkage rod 32 drives the follower 33 to rotate, so that the follower 33 drives the impact block 332 on the abutting portion 331 to impact the fixed wheel 122. The abutting portion 331 exerts an impact force on the fixed wheel 122 to make the slider 12 rotate around the third rotating shaft 13. The rotation of the slider 12 causes the rear cover 11 to rotate synchronously to impact the user's shoulder, and then simulates the recoil generated when the firearm is fired, enabling the user to feel the impact of the recoil during the game, so as to enhance the shooting feeling during the game and improve the user experience satisfaction.
[0049] If during the game process, the user's shoulder does not press against the rear cover 11, at this time, within the movement stroke of the end of the linkage rod 32 close to the drive assembly 2 away from the output end of the drive assembly 2. Therefore, when the trigger is pulled, the recoil simulation device does not generate an impact force, so there is no recoil impact, ensuring the safety of the user when the user has not made prior preparations for the game and avoiding harm to the user due to misoperation.
[0050] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A recoil simulation device for a toy gun, characterized in that: include: A housing, the housing comprising a rear cover, the rear cover being located at one end of the housing and rotatably matched with the housing; A drive assembly is disposed in the housing, and the drive assembly is used to connect with the trigger; A connecting rod assembly is arranged in the outer shell, and the connecting rod assembly is located on one side of the output end of the driving assembly. The connecting rod assembly includes a linkage rod and a follower, and the linkage rod and the follower are rotatably matched. The end of the linkage rod that is not connected to the follower is arranged on the travel path of the output end of the driving assembly; the follower is provided with an abutment portion that contacts the rear cover, and the output end of the driving assembly contacts and presses the linkage rod to make the linkage rod move toward the direction of the rear cover, and the linkage rod drives the follower to rotate so that the abutment portion hits the rear cover.
2. A toy gun recoil simulation device according to claim 1, characterized in that: A connecting plate is provided at one end of the linkage rod that is close to the follower, and a first rotating shaft is provided at one end of the follower that is close to the linkage rod. The first rotating shaft passes through the connecting plate and is rotatably connected to the connecting plate. The first rotating shaft is provided on the motion trajectory of the linkage rod.
3. A toy gun recoil simulation device according to claim 1, characterized in that: It also includes a sleeve arranged on the outer peripheral wall of the linkage rod, and a convex ring is arranged on one end of the inner wall of the sleeve close to the driving assembly; The linkage rod is provided with a first mounting ring, a second mounting ring and a positioning rod, the linkage rod is passed through the first mounting ring and the second mounting ring, an elastic member is provided between the first mounting ring and the second mounting ring, the second mounting ring is slidably connected to the sleeve, the convex ring contacts and presses the first mounting ring; the positioning rod is located at one end of the sleeve close to the rear cover, the positioning rod passes through the linkage rod and is provided at one side of the second mounting ring to press the second mounting ring to compress the elastic member.
4. A toy gun recoil simulation device according to claim 2, characterized in that: It also includes an abutment block arranged on the side of the follower away from the linkage rod, the abutment block is located on the movement track of the connecting plate and / or the follower, and the abutment block is used to limit the movement range of the connecting plate and / or the follower.
5. A toy gun recoil simulation device according to claim 2, characterized in that: The connecting rod assembly also includes a second rotating shaft, one end of which is fixed to the housing, and the other end of which passes through an end of the follower away from the linkage rod and is rotatably connected to the follower.
6. A toy gun recoil simulation device according to claim 5, characterized in that: The abutting portion is located between the first rotating shaft and the second rotating shaft, and the abutting portion is provided with an impact block integrally formed with the abutting portion, and the impact block is used to increase the contact area between the abutting portion and the rear cover.
7. A toy gun recoil simulation device according to claim 6, characterized in that: The rear cover is provided with a slider and a third rotating shaft. The slider is fixedly connected to the rear cover. One end of the third rotating shaft passes through the slider and is arranged on the outer shell. The slider drives the rear cover to be rotatably connected to the outer shell.
8. A toy gun recoil simulation device according to claim 7, characterized in that: A limiting hole is arranged at one end of the slider away from the third rotating shaft, and a limiting rod is arranged on the housing. The limiting rod is passed through the limiting hole to limit the rotation angle of the slider.
9. A toy gun recoil simulation device according to claim 8, characterized in that: The slider is provided with a fixed wheel, the fixed wheel is fixedly connected to the slider and is located between the third rotating shaft and the limiting rod, and the fixed wheel is in contact with the impact block and is slidably connected.
10. A toy gun recoil simulation device according to claim 1, characterized in that: It also includes a mounting plate, which is fixedly connected to the shell and is arranged between the shell and the follower to reduce friction damage of the follower to the inner wall of the shell.