Bidirectional speed limiter of elevator

Abstract

The bidirectional speed limiter comprises a rope wheel, a transmission mechanism, a main shaft, a speed detection mechanism, an action mechanism, a rope clamping device, a spring and an electric switch, the speed detection mechanism comprises an upper platform, a lower platform, a swing arm, a heavy block and a swing connecting rod; when the elevator descends, the rope wheel drives the main shaft to rotate in the first direction, the lower platform provides positive compensation for the lower platform relative to the rotating direction of the upper platform, and the positive compensation is used for applying upward force to the lower platform; when the speed of the elevator reaches a first descending overspeed V1 ', the action mechanism triggers the electric switch to act, and when the speed of the elevator reaches a second descending overspeed V2 ', the action mechanism triggers the rope clamping device to act; when the elevator ascends, the rope wheel drives the main shaft to rotate in the second direction, the lower platform provides negative compensation for the lower platform relative to the rotating direction of the upper platform, and the negative compensation is used for applying downward force to the lower platform; and when the speed of the elevator reaches the first ascending overspeed V1, the action mechanism triggers the electric switch to act.

Description

Technical Field

[0001] The invention relates to the technical field of elevators, and in particular to a bidirectional speed limiter for an elevator. Background Art

[0002] Normally, the upward speed and downward speed of an elevator are the same. The speed limiter is used to detect the overspeed of the elevator and to activate the brake and the elevator safety clamp.

[0003] However, as the speed of elevators increases and the travel distance increases, the air pressure in the elevator car changes dramatically when the elevator goes up and down, causing discomfort to passengers. Studies have found that the human ear is more adaptable to changes in air pressure when the air pressure drops (i.e. when the elevator goes up). To alleviate passenger discomfort, ultra-high-speed elevators need to set the rated speed for down travel lower than the rated speed for up travel.

[0004] Chinese patent document CN201280073318.1 discloses a technical solution. When the car moves up and down, the speed limiter has two independent speed detection mechanisms with different trigger speeds. The disclosed technology has the following problems: 1) The two detection mechanisms isolate or transmit rotation through ratchets, which makes a lot of noise and has poor stability when running at high speed. 2) The use of two detection mechanisms and action trigger mechanisms has a large axial size, which is not conducive to the layout of the elevator room.

[0005] In order to solve the above technical problems, Chinese patent document CN20130027081.X discloses a technical solution, which achieves the design goal by converting the up and down speeds of the car to the speed of the speed detection mechanism through different belt drive ratios, and using a set of speed detection mechanisms. However, it has the following problems: 1) Both the ascending side transmission pulley and the descending side transmission pulley need to have a clutch, which makes a lot of noise and has poor stability when running at high speed. 2) The speed detection mechanism and the belt drive mechanism are arranged in the axial direction at the same time, and the axial size is large, which is not conducive to the layout of the elevator room. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to provide a speed limiter with a simple structure and a small axial size, which can achieve the inconsistency of the rated up and down speeds of an elevator.

[0007] In order to solve the above technical problems, the present invention provides a bidirectional speed limiter for an elevator, comprising a rope wheel, a transmission mechanism, a main shaft, a speed detection mechanism, an action mechanism, a rope clamping device, a spring and an electrical switch;

[0008] The rope wheel drives the main shaft to rotate through the transmission mechanism; the speed detection mechanism rotates coaxially with the main shaft;

[0009] The speed detection mechanism comprises an upper platform, a lower platform, a swing arm, a weight and a swing connecting rod; the upper platform is fixedly connected to the main shaft, the lower platform can slide along the main shaft axis, and the upper platform is parallel to the lower platform; the weight is fixed to one end of the swing arm, the other end of the swing arm is connected to the upper platform through a revolute pair, one end of the swing connecting rod is connected to the middle part of the swing arm through a ball pair, and the other end of the swing connecting rod is hinged to the lower platform through a ball pair;

[0010] There are three swing arms, weights and swing connecting rods. The connection points of the swing arms and the upper platform form a first equilateral triangle, and the connection points of the swing connecting rod and the lower platform form a second equilateral triangle. When the main shaft is in a stationary state, the projections of the corresponding sides of the first equilateral triangle and the second equilateral triangle in the vertical direction are not parallel.

[0011] The main shaft is provided with a spring travel adjustment mechanism, and the spring is arranged between the lower platform and the spring travel adjustment mechanism; the action mechanism is connected with the lower platform;

[0012] When the elevator is going down, the rope wheel drives the main shaft to rotate in the first direction, and the main shaft drives the speed detection mechanism to rotate. The rotation direction of the lower platform relative to the upper platform provides positive compensation to the lower platform. The positive compensation exerts an upward force on the lower platform. The weight moves outward under the action of centrifugal force, driving the lower platform to move upward. When the elevator speed reaches the first overspeed V1' when going down, the action mechanism triggers the electrical switch to act. When the elevator speed reaches the second overspeed V2' when going down, the action mechanism triggers the rope clamp to act.

[0013] When the elevator goes up, the rope pulley drives the main shaft to rotate in the second direction, and the main shaft drives the speed detection mechanism to rotate. The rotation direction of the lower platform relative to the upper platform provides negative compensation to the lower platform. The negative compensation exerts a downward force on the lower platform. The weight moves outward under the action of centrifugal force, driving the lower platform to move upward. When the elevator speed reaches the first overspeed V1 for the upward movement, the action mechanism triggers the electrical switch action.

[0014] Among them, the downward rated speed V0'<the downward first overspeed speed V1'<the downward second overspeed speed V2'<the upward rated speed V0<the upward first overspeed speed V1.

[0015] Preferably, the transmission mechanism is a bevel gear, the rotation axis of the rope pulley is in the horizontal direction, the rotation axis of the main shaft is in the vertical direction, and the rotation axis of the rope pulley and the rotation axis of the main shaft are perpendicular to each other.

[0016] Preferably, the rotation speed of the rope pulley is consistent with that of the main shaft.

[0017] Preferably, the first direction is clockwise and the second direction is counterclockwise; when the main shaft rotates clockwise, the lower platform rotates counterclockwise relative to the upper platform, providing positive compensation to the lower platform; when the main shaft rotates counterclockwise, the lower platform rotates clockwise relative to the upper platform, providing negative compensation to the lower platform.

[0018] Preferably, the first direction is counterclockwise, and the second direction is clockwise; when the main shaft rotates counterclockwise, the lower platform rotates clockwise relative to the upper platform, providing positive compensation to the lower platform; when the main shaft rotates clockwise, the lower platform rotates counterclockwise relative to the upper platform, providing negative compensation to the lower platform.

[0019] Preferably, the action mechanism includes a sleeve, a first rocker arm, a second rocker arm, a bracket and an action rod; the lower platform is connected to the sleeve through a bearing to maintain consistent axial displacement and to allow relative rotation; the sleeve is hinged on the first rocker arm, and the two ends of the first rocker arm are respectively hinged to the second rocker arm and the action rod 53, the second rocker arm is hinged on the bracket, and the bracket is fixedly arranged on the box of the transmission mechanism.

[0020] Preferably, the speed detection mechanism also includes three parallel connecting rods, which are connected to the upper platform and the lower platform respectively through ball joints; the connection points of the parallel connecting rods and the upper platform form a third equilateral triangle, and the connection points of the parallel connecting rods and the lower platform form a fourth equilateral triangle; when the main shaft is in a stationary state, the projections of the corresponding sides of the third equilateral triangle and the fourth equilateral triangle in the vertical direction are not parallel.

[0021] Compared with the prior art, the present invention adopts only one set of speed detection mechanism. Through the spatial structure design of the speed detection mechanism, when the elevator is ascending (faster speed), negative compensation of the force on the lower platform with the rotation direction of the frame is realized, and when the elevator is descending (slower speed), positive compensation of the force on the lower platform with the rotation direction of the frame is realized. No additional adjustment of parts or mechanisms is required, and the size of the mechanism and the operating noise can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0023] Figure 1 This is a schematic diagram of the structure of a bidirectional speed limiter for an elevator according to Embodiment 1;

[0024] Figure 2 It is a schematic diagram of the structure of two speed detection mechanisms in Example 1;

[0025] Figure 3 It is a schematic diagram of the speed detection mechanism of Example 1 realizing positive compensation and negative compensation;

[0026] Figure 4It is a schematic diagram of the action of the bidirectional speed limiter of the elevator in Example 1 when the elevator is moving up and down;

[0027] Figure 5 This is a schematic diagram of the speed detection mechanism of Example 1 driving the action mechanism to move. DETAILED DESCRIPTION

[0028] The following describes the implementation methods of the present invention through specific specific embodiments, and those skilled in the art can fully understand other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific implementation methods, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without deviating from the overall design concept of the invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other in the absence of conflict. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary specific embodiments to those skilled in the art.

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment provides a bidirectional speed limiter for an elevator, including a rope wheel 1, a transmission mechanism 7, a main shaft 2, a speed detection mechanism 3, an action mechanism 5, a rope clamping device 8, a spring 6 and an electrical switch (not shown in the figure).

[0031] The transmission mechanism 7 is a bevel gear, the rotation axis of the rope wheel 1 is in the horizontal direction, the rotation axis of the main shaft 2 is in the vertical direction, and the rotation axis of the rope wheel 1 and the rotation axis of the main shaft 2 are perpendicular to each other.

[0032] When the elevator car goes up and down, the car drives the sheave 1 to rotate through the speed limiter wire rope (not shown in the figure), and the sheave 1 drives the main shaft 2 to rotate through the bevel gear pair, and the rotation speed of the main shaft 2 and the sheave 1 are consistent.

[0033] like Figure 2As shown, the speed detection mechanism includes an upper platform 31, a lower platform 32, a swing arm 33, a weight 34 and a swing link 35; the upper platform 31 is fixedly connected to the main shaft 2, the lower platform 32 is connected to the main shaft 2 through a sliding bearing, the lower platform 32 can slide along the axial direction of the main shaft 2, and the upper platform 31 is parallel to the lower platform 32; the weight 34 is fixed to one end of the swing arm 33, the other end of the swing arm 33 is connected to the upper platform 31 through a revolute pair 44, one end of the swing link 35 is connected to the middle of the swing arm 33 through a ball pair 45, and the other end of the swing link 35 and the lower platform 32 are hinged through a ball pair 46. The main shaft 2 is provided with a spring travel adjustment mechanism, and the spring 6 is arranged between the lower platform 32 and the spring travel adjustment mechanism.

[0034] like Figure 2 As shown in Figure b, there are three swing arms, weights and swing links. The connection points of the swing arms and the upper platform form a first equilateral triangle, and the connection points of the swing links and the lower platform form a second equilateral triangle. When the main shaft is in a stationary state, the projections of the corresponding sides of the first equilateral triangle and the second equilateral triangle in the vertical direction are not parallel. This feature can be seen in Figure 3 It can be clearly seen in b that the swing arm, weight block and swing link constitute the first set of parallel branches, so that the lower platform has two degrees of freedom relative to the upper platform: vertical translation and rotation around the main axis.

[0035] Preferably, a second set of parallel branches can also be constructed, such as Figure 2 As shown in a, the speed detection mechanism also includes three parallel connecting rods 41, and the parallel connecting rods 41 are connected to the upper platform 31 and the lower platform 32 respectively through ball joints 42 and 43; the connection points of the parallel connecting rods 41 and the upper platform 31 form a third equilateral triangle, and the connection points of the parallel connecting rods 41 and the lower platform 32 form a fourth equilateral triangle; when the main shaft 2 is in a stationary state, the projections of the corresponding sides of the third equilateral triangle and the fourth equilateral triangle in the vertical direction are not parallel. These two sets of parallel branches are redundant, and the spatial structure of the first set of parallel branches alone can be adopted, or the redundant spatial structure of two sets of parallel branches can be adopted.

[0036] like Figure 3 As shown in FIG. 2 , since the projections of the corresponding sides of the first equilateral triangle and the second equilateral triangle in the vertical direction are not parallel, that is, the first equilateral triangle and the second equilateral triangle have a preset initial angle; and the projections of the corresponding sides of the third equilateral triangle and the fourth equilateral triangle in the vertical direction are not parallel, that is, the third equilateral triangle and the fourth equilateral triangle also have a preset initial angle. Therefore, if the tilting direction of the swing link or the parallel link is tilted to the right, when the upper platform starts to rotate counterclockwise, when the lower platform rotates clockwise relative to the upper platform, a downward force will be applied to the lower platform, so that the distance between the upper platform and the lower platform increases, as shown in FIG. Figure 3As shown in a; when the upper platform starts to rotate clockwise, the lower platform rotates counterclockwise relative to the upper platform, an upward force is applied to the lower platform, reducing the distance between the upper and lower platforms, as shown in Figure 3 c. Applying a downward force to the lower platform is defined as providing negative compensation to the lower platform, and applying an upward force to the lower platform is defined as providing positive compensation to the lower platform.

[0037] In addition, if the inclination direction of the swing link or the parallel link is to the right, when the upper platform starts to rotate counterclockwise and the lower platform rotates clockwise relative to the upper platform, an upward force will be applied to the lower platform, reducing the distance between the two; when the upper platform starts to rotate clockwise and the lower platform rotates counterclockwise relative to the upper platform, a downward force will be applied to the lower platform, increasing the distance between the two.

[0038] Therefore, the corresponding rotation direction and the corresponding inclination direction of the swing link or parallel link can be selected according to the needs of the layout position of the elevator car and the speed limiter; the ultimate goal is to make the rotation direction of the lower platform relative to the upper platform provide positive compensation to the lower platform when the elevator is descending; and the rotation direction of the lower platform relative to the upper platform provides negative compensation to the lower platform when the elevator is ascending.

[0039] In the latter part of this embodiment, it is explained that when the elevator goes down, the rotation direction of the main shaft is clockwise, and when the elevator goes up, the rotation direction of the main shaft is counterclockwise, that is, the first direction is clockwise and the second direction is counterclockwise.

[0040] like Figure 2 As shown in a, the action mechanism includes a sleeve 51, a first rocker arm 52, a second rocker arm 55, a bracket 54 and an action rod 53; the lower platform 32 is connected to the sleeve 51 through a bearing 56, maintaining consistent axial displacement and being able to rotate relatively; the sleeve 51 is hinged on the first rocker arm 52, and the second rocker arm 55 and the action rod 53 are hinged at both ends of the first rocker arm 52, and the second rocker arm 55 is hinged on the bracket 54, and the bracket 54 is fixedly arranged on the box of the transmission mechanism.

[0041] like Figure 5 As shown, when the lower platform 32 drives the shaft sleeve 51 to move upward, the action rod 53 will be displaced upward. When the displacement of the action rod 53 reaches the first displacement S1, the electrical switch (not shown in the figure) will be triggered to operate, so that the brake is engaged to limit the movement of the car. When the displacement of the action rod 53 reaches the second displacement S2, the rope clamping device will be triggered to operate, clamp the speed limiter wire rope, thereby pulling the car safety clamp to operate and stop the elevator car.

[0042] The following describes the operating speed of the bidirectional speed limiter for the elevator going up and down respectively.

[0043] The elevator has a preset down rated speed V0' and an up rated speed V0, and the bidirectional speed limiter has a preset down first overspeed V1', down second overspeed V2' and up first overspeed V1. Among them, the down rated speed V0'<down first overspeed V1'<down second overspeed V2'<up rated speed V0<up first overspeed V1.

[0044] like Figure 4 As shown in a, when the elevator is going down, the rope wheel drives the main shaft to rotate clockwise, driving the speed detection mechanism to rotate, the weight moves outward under the action of centrifugal force, the swing arm drives the swing connecting rod to move, and the lower platform needs to overcome the pressure of the spring to move upward relative to the upper platform on the one hand, and on the other hand, the lower platform rotates counterclockwise relative to the upper platform to provide positive compensation for the lower platform. As the elevator speed increases, when the elevator speed reaches the first overspeed V1' of the downward direction, the centrifugal force drives the force of the lower platform to move upward, which is recorded as F1', driving the action rod to reach the first displacement S1, triggering the corresponding electrical switch to act. At this time, the angle of the lower platform relative to the upper platform is a1', the positive compensation distance is δX1', the displacement of the lower platform is X1', and the spring force F6' of spring 6 = K6 X1'. When the elevator speed continues to increase to the second overspeed V2' of the downward direction, the centrifugal force drives the force of the lower crossbar to move upward, which is recorded as F2', driving the action rod to reach the second displacement S2, triggering the action of the rope clamping device. At this time, the angle of the lower platform relative to the upper platform is a1", the positive compensation distance is δX1", the displacement of the lower platform is X1", and the spring force of spring 6 is F6"=K6 X1".

[0045] like Figure 4As shown in b, when the elevator goes up, the speed limiter rope pulley drives the main shaft to rotate counterclockwise, drives the speed detection mechanism to rotate, the weight moves outward under the action of centrifugal force, the swing arm drives the swing link to move, and the lower platform needs to overcome the pressure of the spring to move upward relative to the upper platform on the one hand, and on the other hand, the lower platform rotates clockwise relative to the upper platform to provide negative compensation for the lower platform. When the elevator's upward speed reaches the first overspeed speed V1' and the second overspeed speed V2', the angles of the lower platform relative to the upper platform are a2' and a2", respectively, and the negative compensation distances are δX2' and δX2", respectively. The displacement of the lower platform is X2' and X2", and since δX2"<δX2'<0<δX1'<δX1", the spring force F6=K6 X2>F6'=K6 X2'>F6"=K6 X2". At this time, the centrifugal forces F2' and F2" of the weight are not enough to overcome the action of the spring force F6, and the preset stroke cannot be reached, and the electrical switch and the rope clamping device will not be triggered. As the elevator speed increases, when the elevator speed reaches the first overspeed V1 for the upward movement, the centrifugal force F1 of the weight increases. By reasonably designing the displacement of the lower platform, F1 can be made equal to F6 at this time. Therefore, when the elevator speed reaches the first overspeed V1 for the upward movement, the electrical switch will be triggered to stop the car through the brake.

[0046] The present invention has been described in detail above through specific implementation modes and embodiments, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may also make many variations and improvements, which should also be regarded as the protection scope of the present invention.

Claims

1. A bidirectional speed limiter for an elevator, characterized in that: It includes a rope wheel, a transmission mechanism, a main shaft, a speed detection mechanism, an action mechanism, a rope clamping device, a spring and an electrical switch; The rope wheel drives the main shaft to rotate through the transmission mechanism; the speed detection mechanism rotates coaxially with the main shaft; The speed detection mechanism comprises an upper platform, a lower platform, a swing arm, a weight and a swing connecting rod; the upper platform is fixedly connected to the main shaft, the lower platform can slide along the main shaft axis, and the upper platform is parallel to the lower platform; the weight is fixed to one end of the swing arm, the other end of the swing arm is connected to the upper platform through a revolute pair, one end of the swing connecting rod is connected to the middle part of the swing arm through a ball pair, and the other end of the swing connecting rod is hinged to the lower platform through a ball pair; There are three swing arms, weights and swing connecting rods. The connection points of the swing arms and the upper platform form a first equilateral triangle, and the connection points of the swing connecting rod and the lower platform form a second equilateral triangle. When the main shaft is in a stationary state, the projections of the corresponding sides of the first equilateral triangle and the second equilateral triangle in the vertical direction are not parallel. The main shaft is provided with a spring travel adjustment mechanism, and the spring is arranged between the lower platform and the spring travel adjustment mechanism; the action mechanism is connected with the lower platform; When the elevator is going down, the rope wheel drives the main shaft to rotate in the first direction, and the main shaft drives the speed detection mechanism to rotate. The rotation direction of the lower platform relative to the upper platform provides positive compensation to the lower platform. The positive compensation exerts an upward force on the lower platform. The weight moves outward under the action of centrifugal force, driving the lower platform to move upward. When the elevator speed reaches the first overspeed V1' when going down, the action mechanism triggers the electrical switch to act. When the elevator speed reaches the second overspeed V2' when going down, the action mechanism triggers the rope clamp to act. When the elevator goes up, the rope pulley drives the main shaft to rotate in the second direction, and the main shaft drives the speed detection mechanism to rotate. The rotation direction of the lower platform relative to the upper platform provides negative compensation to the lower platform. The negative compensation exerts a downward force on the lower platform. The weight moves outward under the action of centrifugal force, driving the lower platform to move upward. When the elevator speed reaches the first overspeed V1 for the upward movement, the action mechanism triggers the electrical switch to operate. Among them, the downward rated speed V0'<the downward first overspeed speed V1'<the downward second overspeed speed V2'<the upward rated speed V0<the upward first overspeed speed V1.

2. The elevator bidirectional speed limiter according to claim 1, characterized in that: The transmission mechanism is a bevel gear, the rotation axis of the rope wheel is in the horizontal direction, the rotation axis of the main shaft is in the vertical direction, and the rotation axis of the rope wheel and the rotation axis of the main shaft are perpendicular to each other.

3. The elevator bidirectional speed limiter according to claim 1, characterized in that: The rotation speed of the rope pulley is consistent with that of the main shaft.

4. The elevator bidirectional speed limiter according to claim 1, characterized in that: The first direction is clockwise, and the second direction is counterclockwise; when the spindle rotates clockwise, the lower platform rotates counterclockwise relative to the upper platform, providing positive compensation to the lower platform; when the spindle rotates counterclockwise, the lower platform rotates clockwise relative to the upper platform, providing negative compensation to the lower platform.

5. The elevator bidirectional speed governor according to claim 1, characterized in that: The first direction is counterclockwise, and the second direction is clockwise; when the spindle rotates counterclockwise, the lower platform rotates clockwise relative to the upper platform, providing positive compensation to the lower platform; when the spindle rotates clockwise, the lower platform rotates counterclockwise relative to the upper platform, providing negative compensation to the lower platform.

6. The elevator bidirectional speed governor according to claim 1, characterized in that: The action mechanism comprises a shaft sleeve, a first rocker arm, a second rocker arm, a bracket and an action rod; The lower platform is connected to the sleeve through a bearing to keep the axial displacement consistent and to allow relative rotation; the sleeve is hinged on the first rocker arm, the two ends of the first rocker arm are respectively hinged to the second rocker arm and the action rod 53, the second rocker arm is hinged on the bracket, and the bracket is fixedly arranged on the box of the transmission mechanism.

7. The elevator bidirectional speed governor according to claim 1, characterized in that: The speed detection mechanism also includes three parallel connecting rods, which are connected to the upper platform and the lower platform respectively through ball pairs; The connection points of the parallel connecting rod and the upper platform form a third equilateral triangle, and the connection points of the parallel connecting rod and the lower platform form a fourth equilateral triangle; when the main shaft is in a stationary state, the projections of the corresponding sides of the third equilateral triangle and the fourth equilateral triangle in the vertical direction are not parallel.

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