Cam limiting protection device and electric winding drum system

Abstract

An embodiment of the utility model discloses a cam limit protection device and an electric winding drum system, the cam limit protection device comprises an input shaft, a plurality of cam mechanisms and a plurality of switch mechanisms, a first tooth profile is formed on the input shaft, each cam mechanism comprises a transmission worm gear, a cam component and an adjusting component, and the cam component and the adjusting component are mounted on the transmission worm gear. A second tooth profile meshed with the first tooth profile is formed on each transmission worm gear; each switch mechanism is provided with a switch contact, the input shaft can rotate to drive the transmission worm gears to rotate, the cam assemblies can rotate along with the corresponding transmission worm gears to trigger the corresponding switch contacts, and therefore stroke control or start-stop position protection of the cam limiting protection device is triggered. Each adjusting assembly is used for adjusting the rotating position of each cam assembly relative to each transmission worm gear, so that the matching triggering position of the cam assembly and the switch contact is flexibly adjusted, and the limiting of the cam limiting protection device can be flexibly adjusted to dynamically adapt to the change of operating parameters.

Description

Technical Field

[0001] This utility model relates to the field of limit switch technology, and in particular to a cam limit protection device and an electric drum system. Background Technology

[0002] In the field of operation control of electric drum systems, cam limit protection devices, as a traditional mechanical stroke control mechanism, have long been used to protect the start and stop positions of the drum device. Their working principle involves using a cam structure to mechanically trigger and drive a limit switch, thereby constraining the winding and unwinding stroke of the drum.

[0003] However, with the improvement of industrial automation and the development of intelligent control requirements, existing cam limit devices have gradually exposed some problems in electric drum applications. Generally speaking, the mechanical cam adopts a fixed installation structure, which means that its stroke adjustment requires repeated manual disassembly and physical calibration. Especially when switching between multiple working conditions or changing drum parameters, it is impossible to achieve rapid and flexible adjustment of the limit point, which seriously affects the equipment adaptability and operation and maintenance efficiency. Utility Model Content

[0004] The purpose of this invention is to propose a cam limit protection device and an electric drum system, which aims to solve the problem that the existing cam limit protection device is inflexible in limit adjustment and cannot dynamically adapt to changes in operating parameters due to the rigidity of the mechanical structure.

[0005] In a first aspect, this utility model discloses a cam limit protection device, the cam limit protection device comprising:

[0006] An input shaft having a first tooth profile formed thereon;

[0007] A plurality of cam mechanisms, each cam mechanism including a drive worm gear, a cam assembly mounted on the drive worm gear, and an adjusting assembly, wherein each drive worm gear has a second tooth profile that meshes with the first tooth profile, so that each drive worm gear and the input shaft respectively form a worm gear transmission, and each adjusting assembly is used to adjust the rotational position of each cam assembly relative to each drive worm gear; and

[0008] Several switching mechanisms, each of which is provided with switch contacts;

[0009] The input shaft rotation can drive a plurality of the transmission worm gears to rotate, and the plurality of cam assemblies can follow the rotation of the corresponding transmission worm gears to trigger the corresponding switch contacts.

[0010] In one embodiment, each of the cam mechanisms is spaced apart along the extension direction of the input shaft, and a plurality of the switching mechanisms are spaced apart along the extension direction of the input shaft and are arranged in a one-to-one correspondence with each of the cam mechanisms.

[0011] In one embodiment, each of the transmission worm gears includes a worm gear body and a first rod body coaxially disposed with the worm gear body;

[0012] Each of the aforementioned adjustment components includes a first adjustment rod, a first adjustment seat, and an adjustment worm wheel. The adjustment worm wheel is sleeved on the first rod body and is rotatable relative to the first rod body. The first adjustment seat is fixedly disposed on the first rod body. The first adjustment rod has a third tooth profile and is rotatably connected to the first adjustment seat. The adjustment worm wheel has a fourth tooth profile that meshes with the third tooth profile, so that the adjustment worm wheel and the first adjustment rod constitute a worm gear transmission. The cam assembly is sleeved on the first rod body and connected to the adjustment worm wheel.

[0013] Rotating the first adjusting rod can drive the adjusting worm gear to rotate, and the cam assembly can follow the rotation of the adjusting worm gear to change the rotational position of the cam assembly relative to the transmission worm gear.

[0014] In one embodiment, each of the transmission worm gears includes a worm gear body and a first rod body coaxially disposed with the worm gear body;

[0015] Each of the aforementioned adjustment components includes a second adjustment rod, a second adjustment seat, and an adjustment sleeve. The adjustment sleeve is fitted onto the first rod body and is rotatable relative to the first rod body. The second adjustment seat is fixedly mounted on the first rod body and has an adjustment hole. The second adjustment rod passes through the adjustment hole and is threadedly connected to the adjustment hole. A plurality of positioning grooves are formed on the outer peripheral wall of the adjustment sleeve, and the positioning grooves are spaced apart on the outer peripheral wall of the adjustment sleeve. The cam assembly is fitted onto the first rod body and connected to the adjustment sleeve.

[0016] Rotating the second adjusting rod allows the front end of the adjusting rod to extend into or leave the positioning groove, so that the adjusting sleeve and the cam assembly can be fixed or rotated relative to the transmission worm gear.

[0017] In one embodiment, the plurality of cam mechanisms include a first cam module and a second cam module, the first cam module and the second cam module being respectively disposed on both sides of the input shaft; the plurality of switch mechanisms include a first switch module and a second switch module, the first switch module and the second switch module being respectively disposed on both sides of the input shaft.

[0018] Each of the cam mechanisms in the first cam module is spaced apart along the extension direction of the input shaft. Each of the switch mechanisms in the first switch module is spaced apart along the extension direction of the input shaft and is arranged in a one-to-one correspondence with each of the cam mechanisms in the first cam module. Each of the cam mechanisms in the second cam module is spaced apart along the extension direction of the input shaft. Each of the switch mechanisms in the second switch module is spaced apart along the extension direction of the input shaft and is arranged in a one-to-one correspondence with each of the cam mechanisms in the second cam module.

[0019] In one embodiment, the cam assembly includes an adjusting member, and a first cam plate and a second cam plate disposed opposite to each other. A first protrusion is formed on the first cam plate, and a second protrusion is formed on the second cam plate. The first cam and the second cam are rotatable relative to each other to change the overlap range of the first protrusion and the second protrusion, thereby defining the protrusion range of the cam assembly.

[0020] The first cam plate has a fixing hole, and the second cam plate has an arc-shaped hole. The adjusting member can pass through any position of the arc-shaped hole and is detachably connected to the fixing hole to lock and fix the first cam plate and the second cam plate.

[0021] In one embodiment, each of the several switching mechanisms includes a switch body and an elastic connector. The switch body is provided with the switch contacts. One end of the elastic connector is connected to the switch body, and the other end is a free end. The free end can be compressed by the protruding portion of the cam assembly, so that the elastic connector elastically deforms to trigger the switch contacts.

[0022] In one embodiment, the switching mechanism further includes a guide wheel, which is rotatably disposed at the free end.

[0023] In one embodiment, the cam limit protection device further includes a mounting bracket that extends along the extension direction of the input shaft, and a plurality of the switching mechanisms are spaced apart on the mounting bracket.

[0024] Secondly, this utility model also provides an electric drum system, which includes an electric drum device, a control device, and a cam limit protection device according to any of the above embodiments.

[0025] The electric winding device is connected to the input shaft of the cam limit protection device. The cam limit protection device is electrically connected to the control device and is used to output control signals to the control device. The control device is electrically connected to the electric winding device and is used to control the winding and unwinding state of the electric winding device.

[0026] The present invention has the following beneficial effects:

[0027] The cam limit protection device of this invention utilizes an input shaft rotation that drives several transmission worm gears to rotate. Several cam assemblies can follow the corresponding transmission worm gears to rotate and trigger the corresponding switch contacts, thereby triggering the stroke control or start / stop position protection of the cam limit protection device. Furthermore, each cam mechanism includes a transmission worm gear, a cam assembly mounted on the transmission worm gear, and an adjustment assembly. Each transmission worm gear has a second tooth profile that meshes with the first tooth profile, so that each transmission worm gear and the input shaft respectively form a worm gear transmission. Each adjustment assembly is used to adjust the rotational position of each cam assembly relative to each transmission worm gear. By flexibly changing the rotational position of the cam assembly relative to each transmission worm gear, the triggering position of the cam assembly and the switch contacts can be flexibly adjusted, thereby making the limit of the cam limit protection device flexibly adjustable and dynamically adapting to changes in operating parameters.

[0028] When the aforementioned cam limit protection device is applied to an electric drum system, the limit of the cam limit protection device can be flexibly adjusted and dynamically adapted to changes in operating parameters. Therefore, the electric drum system has more diverse functions and is safer and more reliable during operation. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] in:

[0031] Figure 1 This is a schematic diagram of a cam limit protection device in one embodiment.

[0032] Figure 2 for Figure 1 The front view of the cam limit protection device shown.

[0033] Figure 3 for Figure 2 Enlarged schematic diagram of section A in the middle.

[0034] Figure 4 for Figure 1 The diagram shows the structure of the switching mechanism and mounting bracket in the cam limit protection device.

[0035] Figure 5 for Figure 4 Enlarged schematic diagram of section B in the middle.

[0036] Figure 6 for Figure 1 The diagram shows the structure of the cam mechanism in the cam limit protection device.

[0037] Figure 7 for Figure 6 The diagram shows another angle of the cam mechanism.

[0038] Figure 8 for Figure 6 The exploded view of the cam mechanism shown.

[0039] Figure 9 for Figure 6 The top view of the cam mechanism shown.

[0040] Figure 10 for Figure 9 CC section view.

[0041] Figure 11 for Figure 9 DD section view.

[0042] Reference numerals: 100, Input shaft; 110, First tooth profile; 200, Cam mechanism; 210, Transmission worm gear; 211, Second tooth profile; 212, Worm gear body; 213, First rod body; 220, Cam assembly; 221, Adjusting component; 222, First cam plate; 2221, First protrusion; 2222, Fixing hole; 223, Second cam plate; 2231, Second protrusion; 2232, Arc-shaped hole; 230, Adjusting component; 231, First adjusting rod; 232, ... 1. Third tooth profile; 232. First adjusting seat; 233. Adjusting worm gear; 2331. Fourth tooth profile; 240. Bearing; 201. First cam module; 202. Second cam module; 300. Switching mechanism; 310. Switch body; 311. Switch contact; 320. Elastic connector; 330. Guide wheel; 301. First switch module; 302. Second switch module; 400. Connecting bracket; 410. First mounting hole; 420. Second mounting hole; 500. Mounting bracket. Detailed Implementation

[0043] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0044] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0045] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" and "second" may explicitly or implicitly include at least one of the stated features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0046] This utility model discloses a cam limit protection device, which is used to realize stroke control or start / stop position protection of an electric drum device. Please refer to... Figures 1 to 11 In one embodiment, the cam limit protection device includes an input shaft 100, a plurality of cam mechanisms 200, and a plurality of switching mechanisms 300. The input shaft 100 has a first tooth profile 110. Each cam mechanism 200 includes a transmission worm wheel 210, a cam assembly 220 mounted on the transmission worm wheel 210, and an adjustment assembly 230. Each transmission worm wheel 210 has a second tooth profile 211 that meshes with the first tooth profile 110, so that each transmission worm wheel 210 and the input shaft 100 respectively form a worm gear transmission. Each adjustment assembly 230 is used to adjust the rotational position of each cam assembly 220 relative to each transmission worm wheel 210. Each switching mechanism 300 is provided with a switch contact 311.

[0047] In this embodiment, the rotation of the input shaft 100 can drive the rotation of several transmission worm gears 210, and the rotation of several cam assemblies 220 can follow the corresponding transmission worm gears 210 to trigger the corresponding switch contacts 311, thereby triggering the stroke control or start / stop position protection of the cam limit protection device.

[0048] It is understood that each adjustment component 230 is used to adjust the rotational position of each cam component 220 relative to each transmission worm gear 210. By flexibly changing the rotational position of the cam component 220 relative to each transmission worm gear 210, the triggering position of the cam component 220 and the switch contact 311 can be flexibly adjusted, thereby making the limit of the cam limit protection device flexibly adjustable and dynamically adapting to changes in operating parameters.

[0049] In one embodiment, please refer to Figure 2Each cam mechanism 200 is spaced apart along the extension direction of the input shaft 100, and several switching mechanisms 300 are spaced apart along the extension direction of the input shaft 100, corresponding one-to-one with each cam mechanism 200. With this arrangement, one input shaft 100 can simultaneously drive multiple cam mechanisms 200, and each cam mechanism 200 can be set with different trigger positions, thereby satisfying the stroke control or start / stop position protection of the electric drum device.

[0050] Furthermore, the plurality of cam mechanisms 200 include a first cam module 201 and a second cam module 202, which are respectively disposed on both sides of the input shaft 100. The plurality of switch mechanisms 300 include a first switch module 301 and a second switch module 302, which are respectively disposed on both sides of the input shaft 100. Each cam mechanism 200 in the first cam module 201 is spaced apart along the extension direction of the input shaft 100. Each switch mechanism 300 in the first switch module 301 is spaced apart along the extension direction of the input shaft 100 and is arranged in a one-to-one correspondence with each cam mechanism 200 in the first cam module 201. Each cam mechanism 200 in the second cam module 202 is spaced apart along the extension direction of the input shaft 100. Each switch mechanism 300 in the second switch module 302 is spaced apart along the extension direction of the input shaft 100 and is arranged in a one-to-one correspondence with each cam mechanism 200 in the second cam module 202.

[0051] With this configuration, the first cam module 201 and the second cam module 202 on both sides are driven by a single input shaft 100, thereby doubling the number of cam mechanisms 200 to provide a greater number of stroke control or start / stop position triggering functions.

[0052] In addition, by setting it up in this way, the extension length of the input shaft 100 can be reduced while keeping the number of cam mechanisms 200 unchanged, thereby improving the structural stability and operational reliability of the input shaft 100.

[0053] In one embodiment, please refer to Figures 1 to 11Each transmission worm gear 210 includes a worm gear body 212 and a first rod 213 coaxially arranged with the worm gear body 212; each adjustment assembly 230 includes a first adjustment rod 231, a first adjustment seat 232 and an adjustment worm gear 233. The adjustment worm gear 233 is sleeved on the first rod 213 and can rotate relative to the first rod 213. The first adjustment seat 232 is fixedly arranged on the first rod 213. The first adjustment rod 231 has a third tooth 2311 formed on it and is rotatably connected to the first adjustment seat. 232, The adjusting worm wheel 233 has a fourth tooth 2331 that meshes with the third tooth 2311, so that the adjusting worm wheel 233 and the first adjusting rod 231 form a worm gear transmission. The cam assembly 220 is sleeved on the first rod body 213 and connected to the adjusting worm wheel 233. Rotating the first adjusting rod 231 can drive the adjusting worm wheel 233 to rotate, and the cam assembly 220 can follow the rotation of the adjusting worm wheel 233 to change the rotational position of the cam assembly 220 relative to the transmission worm wheel 210.

[0054] With this configuration, the triggering position of the cam assembly 220 and the switch contact 311 can be flexibly adjusted, thereby allowing the limit of the cam limit protection device to be flexibly adjusted and dynamically adapt to changes in operating parameters.

[0055] In addition, by setting the lead angle of the third tooth profile 2311 in the first adjusting rod 231 to be smaller than the equivalent friction angle between the meshing tooth surfaces of the fourth tooth profile 2331 in the adjusting worm wheel 233, the mechanism has self-locking properties and can achieve reverse self-locking, that is, only the worm can drive the worm wheel, and the worm wheel cannot drive the worm. This effectively prevents limit offset or misoperation caused by accidental reverse transmission. At the same time, this self-locking mechanism does not require an additional mechanical locking device, which simplifies the structural complexity. Meanwhile, the precise matching of tooth profile parameters ensures a balance between self-locking reliability and transmission efficiency.

[0056] Specifically, the cam limit protection device also includes a connecting frame 400, and the cam mechanism 200 also includes a bearing 240. The connecting frame 400 includes a first mounting hole 410 and a second mounting hole 420 arranged opposite to each other. A transmission worm gear 210 of the first cam module 201 is mounted in the first mounting hole 410 through the bearing 240 so that the transmission worm gear 210 is rotatably mounted at the first end of the connecting frame 400. A transmission worm gear 210 of the second cam module 202 is mounted in the second mounting hole 420 through the bearing 240 so that the transmission worm gear 210 is rotatably mounted at the second end of the connecting frame 400.

[0057] In another embodiment, each transmission worm gear 210 includes a worm gear body 212 and a first rod body 213 coaxially arranged with the worm gear body 212; each adjustment assembly 230 includes a second adjustment rod, a second adjustment seat, and an adjustment sleeve. The adjustment sleeve is sleeved on the first rod body 213 and can rotate relative to the first rod body 213. The second adjustment seat is fixedly arranged on the first rod body 213 and has an adjustment hole. The second adjustment rod passes through the adjustment hole and is threadedly connected to the adjustment hole. A plurality of positioning grooves are formed on the outer peripheral wall of the adjustment sleeve. The positioning grooves are spaced apart on the outer peripheral wall of the adjustment sleeve. The cam assembly 220 is sleeved on the first rod body 213 and connected to the adjustment sleeve. By operating the second adjustment rod to rotate, the front end of the adjustment rod can be controlled to extend into or leave the positioning groove, so that the adjustment sleeve and the cam assembly 220 can be fixed or rotated relative to the transmission worm gear 210.

[0058] With this configuration, the triggering position of the cam assembly 220 and the switch contact 311 can be flexibly adjusted, thereby allowing the limit of the cam limit protection device to be flexibly adjusted and dynamically adapt to changes in operating parameters. The difference from the previous embodiment is that the limit adjustment accuracy of this cam limit protection device is limited by the number and distribution of the positioning slots, and it cannot achieve the stepless adjustment effect of the worm gear drive in the previous embodiment.

[0059] In one embodiment, please refer to Figures 6 to 11 The cam assembly 220 includes an adjusting member 221 and a first cam plate 222 and a second cam plate 223 disposed opposite to each other. A first protrusion 2221 is formed on the first cam plate 222, and a second protrusion 2231 is formed on the second cam plate. The first cam and the second cam plate can rotate relative to each other to change the overlap range of the first protrusion 2221 and the second protrusion 2231, thereby defining the range of the protruding portion of the cam assembly 220.

[0060] By setting it in this way, the range of the protruding part of the cam assembly 220 can be adjusted by changing the overlap range of the first protrusion 2221 and the second protrusion 2231, thereby adjusting the range of the triggering time between the cam assembly 220 and the switch contact 311, and thus providing a preset stroke control signal command.

[0061] Specifically, the first cam plate 222 has a fixing hole 2222, and the second cam plate 223 has an arc-shaped hole 2232. The adjusting member 221 can pass through any position of the arc-shaped hole 2232 and is detachably connected to the fixing hole 2222 to lock and fix the first cam plate 222 and the second cam plate 223. With this configuration, the adjusting member 221 can be used to change the relative positional relationship between the first cam plate 222 and the second cam plate 223, thereby adjusting the overlap range of the first protrusion 2221 and the second protrusion 2231. Furthermore, the fixing hole 2222 is a threaded hole, and the adjusting member 221 can be a bolt.

[0062] In one embodiment, please refer to Figures 2 to 5 Each of the several switching mechanisms 300 includes a switch body 310 and an elastic connector 320. The switch body 310 is provided with a switch contact 311. One end of the elastic connector 320 is connected to the switch body 310, and the other end is a free end. The free end can be compressed by the protruding part of the cam assembly 220 so that the elastic connector 320 elastically deforms to trigger the switch contact 311.

[0063] With this configuration, when the protruding portion of the cam assembly 220 rotates to the area corresponding to the switching mechanism 300, the protruding portion of the cam assembly 220 can compress the elastic connector 320 to deform, thereby approaching and triggering the switch contact 311.

[0064] Furthermore, the switching mechanism 300 also includes a guide wheel 330, which is rotatably disposed at the free end. By setting the guide wheel 330 to roll with the outer periphery of the cam assembly 220, the smoothness and reliability of the cooperation between the cam assembly 220 and the switching mechanism 300 can be improved.

[0065] In one embodiment, the cam limit protection device further includes a mounting bracket 500 extending along the extension direction of the input shaft 100, on which a plurality of switching mechanisms 300 are spaced apart. This arrangement facilitates the installation of the plurality of switching mechanisms 300. Specifically, the first tooth profile 110 on the input shaft 100 is intermittently arranged.

[0066] Please see Figures 1 to 11 This utility model embodiment also discloses an electric winding system, which includes an electric winding device, a control device, and a cam limit protection device of any of the above embodiments; the electric winding device is connected to the input shaft 100 of the cam limit protection device, the cam limit protection device is electrically connected to the control device and is used to output control signals to the control device, and the control device is electrically connected to the electric winding device and is used to control the winding and unwinding state of the electric winding device.

[0067] Understandably, since the limit of the cam limit protection device can be flexibly adjusted, the cam limit protection device can dynamically adapt to changes in operating parameters by adjusting the different trigger positions of the cam assembly 220 and the switch contact 311 in each cam mechanism 200, as well as the different trigger ranges. Therefore, the electric drum system has more diverse functions and is safer and more reliable during operation.

[0068] Specifically, the multi-stage cam mechanism 200 of the cam limit protection device can trigger and control the electric drum device in segments, such as upper limit control, lower limit control, acceleration control and deceleration control.

[0069] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A cam limit protection device, characterized in that, The cam limit protection device includes: An input shaft having a first tooth profile formed thereon; A plurality of cam mechanisms, each cam mechanism including a drive worm gear, a cam assembly mounted on the drive worm gear, and an adjusting assembly, wherein each drive worm gear has a second tooth profile that meshes with the first tooth profile, so that each drive worm gear and the input shaft respectively form a worm gear transmission, and each adjusting assembly is used to adjust the rotational position of each cam assembly relative to each drive worm gear; and Several switching mechanisms, each of which is provided with switch contacts; The input shaft rotation can drive a plurality of the transmission worm gears to rotate, and the plurality of cam assemblies can follow the rotation of the corresponding transmission worm gears to trigger the corresponding switch contacts.

2. The cam limit protection device according to claim 1, characterized in that, Each of the cam mechanisms is spaced apart along the extension direction of the input shaft, and several of the switching mechanisms are spaced apart along the extension direction of the input shaft, and are arranged in a one-to-one correspondence with each of the cam mechanisms.

3. The cam limit protection device according to claim 2, characterized in that, Each of the aforementioned transmission worm gears includes a worm gear body and a first rod body coaxially disposed with the worm gear body; Each of the aforementioned adjustment components includes a first adjustment rod, a first adjustment seat, and an adjustment worm wheel. The adjustment worm wheel is sleeved on the first rod body and is rotatable relative to the first rod body. The first adjustment seat is fixedly disposed on the first rod body. The first adjustment rod has a third tooth profile and is rotatably connected to the first adjustment seat. The adjustment worm wheel has a fourth tooth profile that meshes with the third tooth profile, so that the adjustment worm wheel and the first adjustment rod constitute a worm gear transmission. The cam assembly is sleeved on the first rod body and connected to the adjustment worm wheel. Rotating the first adjusting rod can drive the adjusting worm gear to rotate, and the cam assembly can follow the rotation of the adjusting worm gear to change the rotational position of the cam assembly relative to the transmission worm gear.

4. The cam limit protection device according to claim 2, characterized in that, Each of the aforementioned transmission worm gears includes a worm gear body and a first rod body coaxially disposed with the worm gear body; Each of the aforementioned adjustment components includes a second adjustment rod, a second adjustment seat, and an adjustment sleeve. The adjustment sleeve is fitted onto the first rod body and is rotatable relative to the first rod body. The second adjustment seat is fixedly mounted on the first rod body and has an adjustment hole. The second adjustment rod passes through the adjustment hole and is threadedly connected to the adjustment hole. A plurality of positioning grooves are formed on the outer peripheral wall of the adjustment sleeve, and the positioning grooves are spaced apart on the outer peripheral wall of the adjustment sleeve. The cam assembly is fitted onto the first rod body and connected to the adjustment sleeve. Rotating the second adjusting rod allows the front end of the adjusting rod to extend into or leave the positioning groove, so that the adjusting sleeve and the cam assembly can be fixed or rotated relative to the transmission worm gear.

5. The cam limit protection device according to any one of claims 2 to 4, characterized in that, The plurality of cam mechanisms include a first cam module and a second cam module, the first cam module and the second cam module being respectively disposed on both sides of the input shaft; the plurality of switch mechanisms include a first switch module and a second switch module, the first switch module and the second switch module being respectively disposed on both sides of the input shaft; Each of the cam mechanisms in the first cam module is spaced apart along the extension direction of the input shaft. Each of the switch mechanisms in the first switch module is spaced apart along the extension direction of the input shaft and is arranged in a one-to-one correspondence with each of the cam mechanisms in the first cam module. Each of the cam mechanisms in the second cam module is spaced apart along the extension direction of the input shaft. Each of the switch mechanisms in the second switch module is spaced apart along the extension direction of the input shaft and is arranged in a one-to-one correspondence with each of the cam mechanisms in the second cam module.

6. The cam limit protection device according to any one of claims 1 to 4, characterized in that, The cam assembly includes an adjusting member, and a first cam plate and a second cam plate disposed opposite to each other. A first protrusion is formed on the first cam plate, and a second protrusion is formed on the second cam plate. The first cam and the second cam are rotatable relative to each other to change the overlap range of the first protrusion and the second protrusion, thereby limiting the range of the protruding portion of the cam assembly. The first cam plate has a fixing hole, and the second cam plate has an arc-shaped hole. The adjusting member can pass through any position of the arc-shaped hole and is detachably connected to the fixing hole to lock and fix the first cam plate and the second cam plate.

7. The cam limit protection device according to any one of claims 1 to 4, characterized in that, Each of the aforementioned switching mechanisms includes a switch body and an elastic connector. The switch body is provided with the switch contacts. One end of the elastic connector is connected to the switch body, and the other end is a free end. The free end can be compressed by the protruding portion of the cam assembly, so that the elastic connector elastically deforms to trigger the switch contacts.

8. The cam limit protection device according to claim 7, characterized in that, The switching mechanism also includes a guide wheel, which is rotatably mounted on the free end.

9. The cam limit protection device according to claim 7, characterized in that, The cam limit protection device also includes a mounting bracket that extends along the extension direction of the input shaft, and a plurality of the switching mechanisms are spaced apart on the mounting bracket.

10. An electric drum system, characterized in that, The electric drum system includes an electric drum device, a control device, and a cam limit protection device as described in any one of claims 1 to 9; The electric winding device is connected to the input shaft of the cam limit protection device. The cam limit protection device is electrically connected to the control device and is used to output control signals to the control device. The control device is electrically connected to the electric winding device and is used to control the winding and unwinding state of the electric winding device.

Images