WO2021093514A1

WO2021093514A1 - Reciprocating saw

Info

Publication number: WO2021093514A1
Application number: PCT/CN2020/121543
Authority: WO
Inventors: 朱伯元; 刘瑞峰
Original assignee: 苏州宝时得电动工具有限公司
Priority date: 2019-11-15
Filing date: 2020-10-16
Publication date: 2021-05-20
Also published as: CN112809087B; CN112809087A

Abstract

Disclosed is a reciprocating saw, comprising a housing (100); an electric motor (200); a transmission mechanism (300), the transmission mechanism being driven by the electric motor to drive a saw blade to move in a reciprocating manner; an object for detection (400) arranged on the transmission mechanism and capable of moving to a first position along with the transmission mechanism, wherein when the object for detection moves to the first position, the reciprocating saw is in a working stroke state or an idle stroke state; a first detector (500) for detecting the object for detection and arranged opposite the first position; and a control circuit board (600), which is electrically connected to the first detector and the electric motor and adjusts the rotation speed of the electric motor when the first detector detects the object for detection. The reciprocating saw can effectively control the rotation speed of the electric motor according to stroke requirements, thereby preventing a cutting speed from being reduced while reducing vibration of the saw blade.

Description

Reciprocating saw

This application claims the priority of the Chinese patent application whose application date is November 15, 2019 and the application number is 201911116784.3, the entire content of which is incorporated into this application by reference.

Technical field

This application relates to the technical field of electric saws, in particular to a reciprocating saw.

Background technique

With the development of science and technology, chainsaws have appeared, bringing convenience to people's production and life. Among them, the reciprocating saw is a kind of electric saw that allows the saw blade to reciprocate for cutting. In a cutting cycle, the reciprocating saw has a working stroke state and an idle stroke state. In the working stroke state, the reciprocating saw moves in one direction and performs cutting work. In the idle stroke state, the reciprocating saw moves in the opposite direction without cutting.

Traditional reciprocating saws are usually difficult to effectively control the speed of the motor, which will lead to various application problems such as low cutting efficiency.

Summary of the invention

Based on this, it is necessary to provide a reciprocating saw that can effectively control the rotation speed of the motor in response to the above technical problems.

A reciprocating saw, which has a working stroke state and an idle stroke state, and is characterized in that it includes:

chassis;

The motor is located in the casing;

A transmission mechanism, the transmission mechanism includes a reciprocating rod, the reciprocating rod is driven by the motor to make a reciprocating motion, thereby causing the saw blade to make a reciprocating motion;

The detected object, the detected object is set on the reciprocating rod, and can move to the first position with the movement of the reciprocating rod, and when the detected object moves to the first position, the reciprocating saw is in the position State the status of the work schedule;

The first detector is used to detect the object to be detected, and is fixed relative to the casing and arranged opposite to the first position. When the object to be detected moves to the first position, the first detector detects all the objects. The first signal is emitted from the detected object;

The control circuit board is electrically connected to the first detector and the motor, and when the first detector detects the object to be detected, it receives the first signal and raises the output according to the first signal pair. State the speed of the motor.

In one of the embodiments, the working stroke state includes a first starting section and a first stable section, the saw blade accelerates in the first starting section, and the speed stability of the first stable section is greater than that of the first stable section. The speed stability of the first initial stage, when the detected object moves to the first position, the reciprocating saw is in the first stable stage.

In one of the embodiments, the working stroke state includes a first starting section and a first stable section, the saw blade accelerates in the first starting section, and the speed stability of the first stable section is greater than that of the first stable section. The speed stability of the first starting section, when the detected object moves to the first position, the reciprocating saw is at the beginning of the first starting section;

When the first detector detects the object to be detected, the control circuit board reduces the rotation speed of the motor, and after a preset time has elapsed, the control circuit board increases the rotation speed of the motor.

In one of the embodiments, when the detected object moves to the first position, the reciprocating saw is in a working stroke state; the detected object can also move to the second position, and when the detected object moves to the second position When the reciprocating saw is in the idle stroke state; the reciprocating saw also includes a second detector for detecting the object to be detected, the second detector is fixed relative to the casing and arranged opposite to the second position And it is electrically connected to the control circuit board. When the detected object moves to the second position, the second detector detects the detected object and sends a second signal to the control circuit board.

In one of the embodiments, the idle stroke state includes a second starting section and a second stable section, the saw blade accelerates in the second starting section, and the speed stability of the second stable section is greater than The speed stability of the second starting section; when the detected object moves to the second position, the reciprocating saw is at the beginning of the second starting section; when the second detector detects the detected object At this time, the control circuit board receives the second signal and reduces the rotation speed of the motor according to the second signal.

In one of the embodiments, the transmission mechanism includes a gear, the gear rotates under the drive of the motor, the reciprocating rod reciprocates under the drive of the gear, and the detected object is arranged on the gear on.

In one of the embodiments, the gear includes a gear body and an eccentric pin provided on the gear body, the gear body is driven by the motor to rotate, and the eccentric pin drives the reciprocating rod to make a reciprocating motion The object to be detected is arranged on the eccentric pin, and is located on opposite sides of the eccentric pin from the gear body.

In one of the embodiments, the detected object is a magnet, and the first detector is a Hall sensor.

In the above-mentioned reciprocating saw, the object to be detected is arranged on the transmission mechanism and moves with the movement of the transmission mechanism, and can move to the first position, and when the object to be detected moves to the first position, the reciprocating saw is in a working stroke state or an idle stroke status. The first detector is used to detect the object to be detected and is arranged opposite to the first position. The control circuit board is electrically connected to the first detector and the motor, and when the first detector detects the object to be detected, the rotation speed of the motor is adjusted. Therefore, the rotation speed of the motor can be effectively controlled according to the travel requirements, thereby solving various application problems. For example, when the detected object moves to the first position, the reciprocating saw is in the working stroke state. At this time, the control circuit board increases the speed of the motor, which can effectively increase the reciprocating speed of the saw blade in the working stroke state, thereby increasing the cutting speed of the saw blade. Prevent the cutting speed of the saw blade from being reduced due to resistance, which can effectively improve the cutting efficiency. Or, for example, when the detected object moves to the first position, the reciprocating saw is in the working stroke state or the beginning of the idle stroke state. At this time, the control circuit board reduces the speed of the motor, effectively reducing the movement speed of the saw blade, thereby reducing the reciprocating saw Vibration.

Description of the drawings

Figure 1 is a perspective view of a reciprocating saw in an embodiment;

Figure 2 is a cross-sectional view of a reciprocating saw in an embodiment;

3 is a schematic top view of the reciprocating saw at the beginning of the first initial section of the working stroke state in an embodiment;

4 is a schematic top view of an embodiment of the reciprocating saw in the first stable section of the working stroke state;

Fig. 5 is a schematic top view of the reciprocating saw at the beginning of the second starting section of the idle stroke state in an embodiment;

Figure 6 is a schematic top view of an embodiment of the reciprocating saw in the second stable section of the idle stroke state;

Figure 7 is a schematic diagram of the phase of the reciprocating saw in an embodiment;

Figure 8 is a cross-sectional view of a reciprocating saw in another embodiment.

Detailed ways

In order to make the purpose, technical solutions, and advantages of this application clearer, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not used to limit the present application.

In one embodiment, a reciprocating saw is provided. 1 to 2, the reciprocating saw includes a housing 100, a motor 200, and a transmission mechanism 300.

The housing 100 is the housing of the reciprocating saw. The motor 200 is placed in the casing 100 to provide a drive for the reciprocating saw. The transmission mechanism 300 is driven by the motor 200. And drive the saw blade (not shown) to reciprocate. Specifically, the front end of the transmission mechanism 300 may include a chuck 301. The saw blade is clamped on the chuck 301 and then reciprocates under the drive of the transmission mechanism 300.

The saw blade completes the cutting work during the reciprocating motion. Its reciprocating time is a cutting cycle. In a cutting cycle, the reciprocating saw has a working stroke state and an idle stroke state. When the reciprocating saw is in a working stroke state, the saw blade is usually in a state of retracting backward (that is, moving from a position away from the casing 100 to a position close to the casing 100). When the reciprocating saw is in the idle stroke state, the saw blade is usually in a forward motion state (that is, moving from a position close to the casing 100 to a position away from the casing 100).

At the same time, the reciprocating saw of this embodiment also includes an object to be detected 400, a first detector 500, and a control circuit board 600.

The detected object 400 and the first detector 500 are a pair of detection components that can cooperate with each other. When the object 400 is opposite to the first detector 500, it can be detected by the first detector 500. Specifically, the detected object 400 may be a magnet, and the first detector 500 may be a Hall sensor. Of course, this application is not limited to this, and the detected object 400 and the first detector 500 may also be other detection components that can cooperate with each other.

The control circuit board 600 is electrically connected to the first detector 500 and the motor 200, and can further adjust the rotation speed of the motor 200 according to the detection situation of the detected object 400 by the first detector 500.

The detected object 400 is arranged on the transmission mechanism 300 and can move with the movement of the transmission mechanism 300. The object 400 can be moved to the first position. The first detector 500 is fixed relative to the casing 100 and arranged opposite to the first position.

Therefore, when the detected object 400 moves to the first position, the detected object 400 faces the first detector 500 and can be detected by the first detector 500. When the detected object 400 moves to another position, the detected object 400 and the first detector 500 are not opposite, and cannot be detected by the first detector 500.

Therefore, when the detected object 400 moves to the first position, the first detector 500 detects the detected object 400. At this time, the first detector 500 can send a first signal and send the first signal to the control circuit board 600. The control circuit board 600 receives the first signal and adjusts the rotation speed of the motor 200 according to the first signal.

At the same time, the first position set in this embodiment is a position that satisfies the following conditions: when the detected object 400 moves to the first position, the reciprocating saw is in a working stroke state. Therefore, when the first detector 500 detects the object 400, it means that the reciprocating saw is in a working stroke state. At this time, the control circuit board 600 adjusts the rotation speed of the motor 200, and can further adjust the rotation speed of the motor 200 according to the requirements of the working stroke state.

Alternatively, the first position set in this embodiment is a position that satisfies the following conditions: when the detected object 400 moves to the first position, the reciprocating saw is in an idle stroke state. Therefore, when the first detector 500 detects the detected object 400, it means that the reciprocating saw is in the idle stroke state. At this time, the control circuit board 600 adjusts the rotation speed of the motor 200, and can further adjust the rotation speed of the motor 200 according to the requirements of the idle stroke state.

Here, the control circuit board 600 adjusting the rotation speed of the motor 200 refers to controlling the output power to the motor, thereby adjusting the rotation speed of the motor 200.

Therefore, this embodiment can effectively control the rotation speed of the motor 200 according to the stroke requirement, thereby solving various application problems.

Specifically, in one embodiment, when the detected object 400 moves to the first position, the reciprocating saw is in a working stroke state. Therefore, when the first detector 500 detects the object 400, it means that the reciprocating saw is in a working stroke state.

At this time, the present embodiment controls the circuit board 600 to increase the rotation speed of the motor 200. The motor 200 drives the transmission mechanism 300 to drive the saw blade to reciprocate. Therefore, at this time, the reciprocating speed of the saw blade (that is, the cutting speed) under the working stroke state can be increased.

With traditional reciprocating saws, the saw blade performs cutting work under the working stroke state. The object to be cut will give the saw blade a resistance, which reduces the cutting speed of the saw blade.

The reciprocating saw of this embodiment increases the rotation speed of the motor 200 at this time, thereby increasing the cutting speed of the saw blade, and preventing the cutting speed of the saw blade from being reduced due to resistance. Therefore, this embodiment can effectively improve the cutting efficiency.

Specifically, referring to FIGS. 3 and 4, the working stroke state of the reciprocating saw includes a first starting section and a first stable section. Because the saw blade moves in the opposite direction in the idle stroke state and the working stroke state. Therefore, when it changes from the idle stroke state to the working stroke state, the direction of movement of the saw blade changes and it undergoes a stage of accelerated movement, which is the first initial stage. After that, the speed of the saw blade tends to stabilize, and this stage is the first stable stage. The speed stability of the first stable section is greater than the speed stability of the first initial section.

In the first initial stage, when the saw blade moves from the idle stroke state to the working stroke state, the direction of movement of the saw blade changes, so there will be a vibration at this time. If the movement speed of the saw blade is too high at this time, the vibration phenomenon will be more serious. Therefore, in order to improve the cutting efficiency and not increase the vibration of the reciprocating saw, this embodiment can be specifically configured to set the reciprocating saw in the first stable stage when the detected object 400 moves to the first position.

Further, it can be set that when the detected object 400 moves to the first position, the reciprocating saw is at the beginning of the first stable section. At this time, increasing the rotation speed of the motor 200 can increase the cutting speed of the saw blade as early as possible without increasing the vibration of the reciprocating saw, thereby increasing the cutting efficiency more effectively.

Of course, this embodiment is not limited to this, and it can also be set that when the detected object 400 moves to the first position, the reciprocating saw is in the first starting section.

In one embodiment, it is set when the object 400 to be detected moves to the first position, the reciprocating saw is at the beginning of the first starting section of the working stroke state. At the same time, when the first detector 500 detects the detected object 400, the control circuit board 600 first reduces the rotation speed of the motor 200, and then increases the rotation speed of the motor 200.

As explained in the foregoing embodiment, in the first initial stage, when the saw blade moves from the idle stroke state to the working stroke state, the direction of movement of the saw blade changes, so there will be a vibration at this time. In this embodiment, when the detected object 400 moves to the first position, the reciprocating saw is at the beginning of the first starting section of the working stroke state, that is, when the reciprocating saw is in the idle stroke state and just transitions to the working stroke state.

At this time, the control circuit board 600 reduces the rotation speed of the motor 200, which can effectively reduce the movement speed of the saw blade, and thereby can reduce the vibration of the reciprocating saw. After that, the control circuit board 600 further increases the rotation speed of the motor 200, thereby increasing the cutting speed of the subsequent saw blade, thereby improving the cutting efficiency. Therefore, this embodiment can not only effectively prevent the vibration of the reciprocating saw, but also effectively improve the cutting efficiency.

Specifically, the control circuit board 600 can be set to increase the rotation speed of the motor 200 after a preset time has elapsed after reducing the rotation speed of the motor 200. The "preset time" here can be set according to actual needs, and this application has no limitation on this.

In one embodiment, when the detected object 400 moves to the first position, the reciprocating saw is in a working stroke state. In addition, the detected object 400 can also move to the second position, and when the detected object 400 moves to the second position, the reciprocating saw is in an idle stroke state.

The reciprocating saw also includes a second detector 700 for detecting the object to be detected. When the detected object 400 is a magnet, the second detector 700 may also be a Hall sensor. The second detector 700 is fixed relative to the casing 100 and is arranged opposite to the second position, and is electrically connected to the control circuit board 600.

Therefore, when the detected object 400 moves to the second position, the second detector 700 detects the detected object 400. At this time, the second detector 500 can send a second signal and send the second signal to the control circuit board 600.

Therefore, in this embodiment, when the detected object 400 moves to the first position, the detected object 400 is opposed to the first detector 500 and is detected by the first detector 500, but is not detected by the second detector 700. To. At this time, the control circuit board 600 only receives the first signal but not the second signal, which indicates that the reciprocating saw is in the working stroke state.

When the detected object 400 moves to the second position, the detected object 400 faces the second detector 700 and is detected by the second detector 700 instead of the first detector 700. At this time, the control circuit board 600 only receives the second signal but not the first signal, which indicates that the reciprocating saw is in the idle stroke state.

Therefore, the control circuit board 600 of this embodiment can combine the detection conditions of the first detector 500 and the second detector 700 to more accurately determine which stroke state the reciprocating saw is in, and then accurately adjust the rotation speed of the motor 200 .

In one embodiment, referring to FIGS. 5 and 6, the idle stroke state includes a second starting section and a second stable section. Because the saw blade moves in the opposite direction in the idle stroke state and the working stroke state. Therefore, when it changes from the working stroke state to the idle stroke state, the direction of the saw blade's movement changes and it undergoes a stage of accelerated movement, which is the second initial stage. After that, the saw blade speed tends to stabilize, and this stage is the second stable stage. The speed stability of the second stable section is greater than the speed stability of the second initial section.

In the second initial stage, when the working stroke state just transitions to the idle stroke state, the direction of movement of the saw blade changes, so there will be a vibration at this time. If the movement speed of the saw blade is too high at this time, the vibration phenomenon will be more serious.

In this embodiment, when the detected object 400 moves to the second position, the reciprocating saw is at the beginning of the second initial stage, that is, when the reciprocating saw is in the idle stroke state and just transitions to the working stroke state. When the second detector 700 detects the object 400, the control circuit board 600 receives the second signal and reduces the rotation speed of the motor 200 according to the second signal. In turn, the movement speed of the saw blade can be effectively reduced, and the vibration of the reciprocating saw can be reduced.

In one embodiment, referring to FIGS. 3 to 6, the transmission mechanism 300 includes a gear 310 and a reciprocating rod 320, and the gear 310 is driven by the motor 200 to rotate. The reciprocating rod 320 is driven by the gear 310 to reciprocate. The object 400 to be detected is arranged on the gear 310. The chuck 301 of the transmission mechanism 300 may be specifically arranged at the front end of the reciprocating rod 320. The saw blade is clamped on the chuck 301.

The gear 310 may include a gear body 311 and an eccentric pin 312 provided on the gear body 311. The gear body 311 is driven by the motor 200 to rotate. Specifically, referring to FIG. 7, the outer side of the gear body 311 may be provided with first gear teeth 3111. The motor 200 has an output shaft 210, and the outer side of the output shaft 210 has a second gear 211. The first gear 3111 meshes with the second gear 211, so that the gear body 311 is driven by the motor 200 to rotate. Of course, the specific structure of the gear body 311 and the motor 200 may also be different from this. For example, the gear body 311 is directly arranged on the output shaft of the motor 200, which is not limited in the present application.

The eccentric pin 312 is disposed on the gear body 311 and therefore rotates with the rotation of the gear body 311. The reciprocating rod 320 is driven by the eccentric pin 312 to make a reciprocating movement. Specifically, referring to the figure, one end of the reciprocating rod 320 opposite to the chuck 301 may be provided with a strip-shaped limiting hole 320a. The eccentric pin 312 is inserted into the limiting hole 320a. When the eccentric pin 312 rotates, there is no resistance in the vertical direction of the strip-shaped limiting hole 320a, and the resistance of the reciprocating rod 320 in the left-right direction of the strip-shaped limiting hole 320a gives the reciprocating rod 320 a left-to-right direction. Reaction force. Therefore, the eccentric pin 312 can drive the reciprocating rod 320 to reciprocate.

In this embodiment, specifically, in order to facilitate design, the detected object 400 may be disposed on the eccentric pin 312 and located on the opposite sides of the eccentric pin 312 from the gear body 311. Of course, the detected object 400 can also be arranged in other positions of the gear, which is not limited in this application.

Referring to FIG. 7, when the detected object 400 is set on the gear 310, the connection line between the detected object 400 (specifically set on the eccentric pin 312 in FIG. 7) and the center of the gear 310 and the forward direction of the reciprocating rod 320 are clamped. The angle is the phase angle. Then when the phase angle is 0°, the reciprocating saw is at the beginning of the working stroke state. When the phase angle is 180°, the reciprocating saw is at the beginning of the idle stroke state.

In this embodiment, the transmission mechanism 300 includes a gear 310 and a reciprocating rod 320. The test object 400 is arranged on the gear 310 of the transmission mechanism 300. However, this application is not limited by this. For example, in other embodiments, referring to FIG. 8, the transmission mechanism 300 includes a reciprocating rod 320. The reciprocating rod 320 reciprocates under the drive of the motor 200, thereby causing the saw blade to reciprocate, and the detected object 400 is arranged on the reciprocating rod. The detected object 400 may also be arranged on the reciprocating rod 320.

The specific position of the detected object 400 on the reciprocating rod 320 can be set with reference to the position of the first detector 500 during design, so that the detected object 400 can move to the first position relative to the first detector 500. When the reciprocating saw also includes a second detector 700 for detecting the object 400, the specific position of the object 400 on the reciprocating rod 320 can be referred to the first detector 500 and the second detector 700 in the design. The position of the object 400 can be set so that the detected object 400 can move to a first position opposite to the first detector 500 and a second position opposite to the second detector 700.

The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be It is considered as the range described in this specification.

The above-mentioned embodiments only express several implementation manners of the present application, and their description is relatively specific and detailed, but they should not be understood as a limitation on the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can be made, and these all fall within the protection scope of this application. Therefore, the scope of protection of the patent of this application shall be subject to the appended claims.

Claims

A reciprocating saw, which has a working stroke state and an idle stroke state, and is characterized in that it includes:

chassis;

The motor is located in the casing;

A transmission mechanism, the transmission mechanism includes a reciprocating rod, the reciprocating rod is driven by the motor to make a reciprocating motion, thereby causing the saw blade to make a reciprocating motion;

The detected object, the detected object is set on the reciprocating rod, and can move to the first position with the movement of the reciprocating rod, and when the detected object moves to the first position, the reciprocating saw is in the position State the status of the work schedule;

The first detector is used to detect the object to be detected, and is fixed relative to the casing and arranged opposite to the first position. When the object to be detected moves to the first position, the first detector detects all the objects. The first signal is emitted from the detected object;

The control circuit board is electrically connected to the first detector and the motor, and when the first detector detects the object to be detected, it receives the first signal and raises the output according to the first signal pair. State the speed of the motor.
The reciprocating saw according to claim 1, wherein:

The working stroke state includes a first starting section and a first stable section, the saw blade accelerates in the first starting section, and the speed stability of the first stable section is greater than the speed stability of the first starting section When the detected object moves to the first position, the reciprocating saw is in the first stable section.
The reciprocating saw according to claim 1, wherein:

The working stroke state includes a first starting section and a first stable section, the saw blade accelerates in the first starting section, and the speed stability of the first stable section is greater than the speed stability of the first starting section When the detected object moves to the first position, the reciprocating saw is at the beginning of the first starting section;

When the first detector detects the object to be detected, the control circuit board reduces the rotation speed of the motor, and after a preset time has elapsed, the control circuit board increases the rotation speed of the motor.
The reciprocating saw according to any one of claims 1-3, characterized in that:

When the detected object moves to the first position, the reciprocating saw is in a working stroke state;

The detected object can also move to a second position, and when the detected object moves to the second position, the reciprocating saw is in an idle stroke state;

The reciprocating saw also includes a second detector for detecting the object to be detected. The second detector is fixed relative to the casing and arranged opposite to the second position and is electrically connected to the control circuit board. When the detected object moves to the second position, the second detector detects the detected object and sends a second signal to the control circuit board.
The reciprocating saw according to claim 4, wherein:

The idle stroke state includes a second starting section and a second stable section, the saw blade accelerates in the second starting section, and the speed stability of the second stable section is greater than that of the second starting section Speed stability;

When the detected object moves to the second position, the reciprocating saw is at the beginning of the second starting section;

When the second detector detects the object to be detected, the control circuit board receives the second signal and reduces the rotation speed of the motor according to the second signal.
The reciprocating saw according to claim 1, wherein the transmission mechanism comprises a gear, the gear is driven by the motor to rotate, the reciprocating rod is driven by the gear to reciprocate, and the The detection object is arranged on the gear.
The reciprocating saw according to claim 6, wherein the gear includes a gear body and an eccentric pin provided on the gear body, the gear body is driven by the motor to rotate, and the eccentric pin drives The reciprocating rod makes a reciprocating motion, and the detected object is arranged on the eccentric pin, and is located on opposite sides of the eccentric pin with the gear body.
The reciprocating saw according to claim 1, wherein the detected object is a magnet, and the first detector is a Hall sensor.