Novel safety brake and hoisting mechanism

Abstract

The utility model relates to the technical field of braking, and discloses a novel safety brake and a hoisting mechanism, the safety brake comprises a rack, a rotating shaft, a ratchet wheel, a pawl, a spring assembly, an encoder, an electric push rod and a PLC controller; the rotating shaft is rotationally mounted on the rack; the ratchet is fixedly mounted at the end of the rotating shaft; the pawl is rotationally installed on the rack close to the ratchet wheel, the tail end of the pawl is connected with the spring assembly, and the spring assembly is used for pulling up the pawl to be separated from the ratchet wheel; the tail end of the pawl is further provided with a driving lever, and an electric push rod used for pushing the driving lever is arranged over the driving lever. The encoder and the rotating shaft are connected and mounted on the rack; the PLC is in electric signal connection with the electric push rod and the encoder. The PLC is used for reading pulse signals output by the encoder in real time to calculate the rotating speed of the rotating shaft, the rotating speed is compared with the rated rotating speed, and once overspeed occurs, the electric push rod can be controlled to push the deflector rod, so that the pawl is inserted into a tooth groove of the ratchet wheel to achieve braking.

Description

Technical Field

[0001] The utility model relates to the technical field of braking, in particular to a novel safety brake and a lifting mechanism, which can be used as a safety protection device for the lifting mechanism in a crane or an electric hoist. Background Art

[0002] Ratchet and pawl safety brakes are widely used in the lifting mechanism of metallurgical hoists. The safety brake adopts the working principle of ratchet 3 and pawl 4. Figure 1 As shown, the ratchet is a two-semicircle structure, connected by screws and mounted on the reel, and the ratchet 3 is equipped with a curved disc 3.1. The pawl 4 is fixed to the frame 1 through a rotating shaft, and the pawl 4 is equipped with a roller 4.1, which swings with the curved disc 3.1 on the ratchet 3.

[0003] During normal operation, the ratchet and the curve disc rotate normally with the reel, and the roller on the pawl rotates with the curve disc, driving the pawl to swing, and the safety brake has no braking effect.

[0004] When any part failure of the metallurgical hoist causes the reel to lose control (such as broken motor shaft, broken gear teeth, broken output shaft, etc.), the reel speed increases due to the free fall of the hook weight, and the roller on the pawl also accelerates with the rotation of the curve disk. Under the action of centrifugal force, the swinging amplitude of the ratchet increases; generally, when the weight slides down quickly about 500mm, the roller will be separated from the curve disk, and the ratchet can be inserted into the tooth groove of the ratchet, the ratchet and reel stop rotating, and the safety brake realizes the braking effect.

[0005] The limitation of this safety brake is that if the drum loses control and causes the heavy object to slide down quickly, the roller will also speed up with the rotation of the curve plate. Under the action of centrifugal force, the roller will be separated from the curve plate, and the pawl can be inserted into the tooth groove of the ratchet wheel to achieve the braking function. If the heavy object slides down slowly, the sliding distance is not enough, or the hook is running, the drum speed is not enough, the pawl cannot be inserted into the tooth groove of the ratchet wheel, and the braking function cannot be achieved, which is easy to cause safety accidents.

[0006] Based on this, the present application provides a new safety brake and lifting mechanism with high safety and the ability to brake at a set speed. Utility Model Content

[0007] The utility model aims to solve the technical problems existing in the prior art. To this end, the utility model provides a new safety brake and a lifting mechanism which are highly safe and can brake at a set speed.

[0008] The technical solution adopted by the utility model to solve its technical problems is:

[0009] In the first aspect, a new type of safety brake is provided, including a frame, a rotating shaft, a ratchet, a pawl, a spring assembly, an encoder, an electric push rod and a PLC controller, wherein: the rotating shaft is rotatably mounted on the frame; the ratchet is fixedly mounted on the end of the rotating shaft; the pawl is rotatably mounted on the frame close to the ratchet, and its tail end is connected to the spring assembly, and the spring assembly is used to pull up the pawl to separate it from the ratchet; a lever is also provided at the tail end of the pawl, and an electric push rod for pushing the lever is provided directly above the lever; the encoder is installed on the frame in connection with the rotating shaft; and the PLC controller connects the electric push rod and the encoder by electrical signals.

[0010] In some optional embodiments, the spring assembly is arranged on the frame on one side close to the ratchet, and includes a spring, an adjusting screw and an ear plate, the ear plate is fixed to the frame, the adjusting screw is threadedly connected to the ear plate, one end of the spring is connected to the pawl, and the other end is connected to the adjusting screw.

[0011] In some optional embodiments, the shaft head of the rotating shaft passes through the frame and is connected to an encoder fixed on the frame.

[0012] In some optional embodiments, a longitudinal waist-shaped hole is provided on the frame at the position of the shifting rod, and the shifting rod passes through the waist-shaped hole and abuts against the electric push rod fixed to the frame.

[0013] In some optional embodiments, the ratchet is two semicircular structures, which are fixed to the ends of the rotating shaft by screws.

[0014] In some optional embodiments, the PLC controller is also connected to a driving device that controls the rotation of the shaft via an electrical signal.

[0015] In a second aspect, a lifting mechanism is provided, comprising the novel safety brake, wherein the rotating shaft in the brake is a drum for winding ropes.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] The utility model utilizes PLC to read the pulse signal output by the encoder in real time to calculate the rotation speed (or lifting speed) of the rotating shaft (or reel), and compares it with the rated rotation speed (or lifting speed). Once overspeed occurs, the power of the rotating shaft (or reel) can be cut off, and at the same time, the electric push rod is controlled to push the lever so that the pawl is inserted into the tooth groove of the ratchet to realize braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0019] Figure 1 It is the internal structure diagram of the safety brake of the existing lifting mechanism;

[0020] Figure 2 It is a partial cross-sectional view of the novel safety brake provided by the utility model;

[0021] Figure 3 It is the internal structure diagram of the new safety brake provided by the utility model;

[0022] Figure 4 yes Figure 2 Left side view provided.

[0023] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0024] 1—frame, 1.1—lumbar hole, 2—rotating shaft, 3—ratchet, 3.1—curve plate, 4—pawl, 4.1—roller, 4.2—lever, 5—spring assembly, 5.1—spring, 5.2—adjusting screw, 5.3—ear plate, 6—encoder, 7—electric push rod. DETAILED DESCRIPTION

[0025] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating positions or positional relationships are based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operate in a specific position, and therefore cannot be understood as limiting the present invention;

[0028] In addition, the descriptions involving the terms "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. The terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0029] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0030] Embodiment 1

[0031] As attached Figure 2 To Attachment Figure 4 As shown, this embodiment provides a new safety brake, including a frame 1, a rotating shaft 2, a ratchet 3, a pawl 4, a spring assembly 5, an encoder 6, an electric push rod 7 and a PLC controller (not shown in the figure), wherein:

[0032] The rotating shaft 2 is rotatably mounted on the frame 1; the ratchet 3 is fixedly mounted on the end of the rotating shaft 2; preferably, as shown in the attached Figure 1 As shown, the ratchet 3 is a two-semicircle structure, which is fixedly mounted on the end of the rotating shaft 2 by screws; the ratchet 4 is rotatably mounted on the frame 1 close to the ratchet 3, and its tail end is connected to the spring assembly 5, and the spring assembly 5 is used to pull up the ratchet to separate it from the ratchet 3; the tail end of the ratchet 4 is also provided with a lever 4.2, and an electric push rod 7 for pushing the lever is provided just above the lever 4.2; the encoder 6 is connected to the rotating shaft 2 and installed on the frame 1; the PLC controller electric signal connects the electric push rod 7 and the encoder 6. This embodiment uses the PLC to read the pulse signal output by the encoder in real time to calculate the rotation speed of the rotating shaft, and compare it with the rated speed. Once overspeed occurs, the electric push rod can be controlled to push the lever, so that the ratchet is inserted into the tooth groove of the ratchet to achieve braking.

[0033] Preferably, as attached Figure 3As shown, the spring assembly 5 is arranged on the frame 1 at a side close to the ratchet 3, and includes a spring 5.1, an adjusting screw 5.2 and a lug 5.3, wherein the lug 5.3 is fixed to the frame 1, the adjusting screw 5.2 is threadedly connected to the lug 5.3, one end of the spring 5.1 is connected to the ratchet 4, and the other end is connected to the adjusting screw 5.2. The spring assembly can adjust the elastic force of the spring through the adjusting screw.

[0034] Preferably, as attached Figure 2 As shown, the shaft head of the rotating shaft 2 passes through the frame 1 and is connected to the encoder 6 fixed on the frame.

[0035] Preferably, as attached Figure 4 As shown, a longitudinal waist-shaped hole 1.1 is provided on the frame 1 at the position of the shifting rod 4.2, and the shifting rod 4.2 passes through the waist-shaped hole 1.1 and abuts against the electric push rod 7 fixed on the frame 1.

[0036] Embodiment 2

[0037] Repeating the first embodiment, the PLC controller of this embodiment is also connected to the driving device (not shown) for controlling the rotation of the rotating shaft by electrical signals. This design can cut off the power of the rotating shaft when overspeed is detected, and at the same time control the electric push rod to push the lever so that the pawl is inserted into the tooth groove of the ratchet wheel to achieve braking.

[0038] Application Examples

[0039] A lifting mechanism includes the novel safety brake described in the second embodiment, wherein the rotating shaft 2 in the brake is a drum for winding ropes. In this embodiment, the PLC reads the pulse signal output by the encoder in real time to calculate the lifting speed of the drum, and compares it with the rated lifting speed. Once overspeed occurs, the power of the drum can be cut off, and the electric push rod is controlled to push the lever, so that the pawl is inserted into the tooth groove of the ratchet wheel to achieve braking.

[0040] When the lifting mechanism stops working, the PLC controller can also read the encoder output pulse signal in real time. At this time, if there is a hook slip phenomenon, the PLC controller will send an action command to the electric push rod. The electric push rod pushes the lever on the pawl, and the pawl is inserted into the tooth groove of the ratchet. The ratchet and the reel stop rotating to prevent the hook from slipping, ensuring safer operation of the equipment.

[0041] It is worth noting that: after detecting overspeed or hook slippage, the PLC controller also sends out an alarm signal, and the alarm signal is preferably an audible and visual alarm signal to remind the operator that the equipment has a fault and ensure the safety of the operation.

[0042] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A new type of safety brake, comprising a frame and a rotating shaft rotatably mounted on the frame; characterized in that: It also includes a ratchet, a pawl, a spring assembly, an encoder, an electric push rod and a PLC controller, wherein: The ratchet is fixedly mounted on the end of the rotating shaft; The pawl is rotatably mounted on the frame close to the ratchet wheel, and its tail end is connected to a spring assembly, and the spring assembly is used to pull up the pawl to separate it from the ratchet wheel; A lever is also provided at the tail end of the ratchet, and an electric push rod for pushing the lever is provided directly above the lever; The encoder is connected to the rotating shaft and installed on the frame; The PLC controller electrical signal connects the electric push rod and the encoder.

2. The novel safety brake according to claim 1 is characterized in that: The spring assembly is arranged on the frame at a side close to the ratchet wheel, and comprises a spring, an adjusting screw and an ear plate. The ear plate is fixed on the frame, the adjusting screw is threadedly connected to the ear plate, one end of the spring is connected to the ratchet, and the other end is connected to the adjusting screw.

3. The new safety brake according to claim 1 is characterized in that: The shaft head of the rotating shaft passes through the frame and is connected to an encoder fixed on the frame.

4. The novel safety brake according to claim 1 is characterized in that: A longitudinal waist-shaped hole is arranged on the frame at the position of the shifting rod, and the shifting rod passes through the waist-shaped hole and abuts against the electric push rod fixed on the frame.

5. The novel safety brake according to claim 1 is characterized in that: The ratchet is two semicircular structures and is fixed to the end of the rotating shaft by screws.

6. The novel safety brake according to claim 1 is characterized in that: The PLC controller is also connected to a driving device for controlling the rotation of the rotating shaft via an electrical signal.

7. A lifting mechanism, characterized in that: It comprises the novel safety brake as described in any one of claims 1 to 6, wherein the rotating shaft in the brake is a drum for winding ropes.

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