Obstruction detection column and using method therefor

Abstract

An obstruction detection column adapted to a wider load range and a using method therefor. The obstruction detection column comprises: an electric motor box (1) and a telescopic supporting assembly, wherein a connector (2) at an upper end of the telescopic supporting assembly is connected to the electric motor box (1) by means of a screw (3), and an elastic piece (5) is mounted on a stepped portion (4) of the connector (2) by means of the screw (3) and then is locked to the electric motor box (1); and a deformation space is formed on the stepped portion (4) surrounding the screw (3); a sensing piece (6) is arranged on the elastic piece (5) to detect an obstruction condition; and when the load on the column increases, a downward force applied to the elastic piece (5) by the screw (3) increases, and the elastic piece (5) undergoes a deformation of its center bending downwards and recessed in the deformation space and sinks as the load increases. A method for using a column, comprising the steps of assembly, loading, and obstruction detection after loading, which include: firstly mounting a connector (2), an elastic piece (5), a screw (3) and a sensing piece (6) into an electric motor box (1), and applying a pre-tightening force to the elastic piece (5) by using the screw (3), such that the elastic piece (5) has an initial deformation; and then increasing the load on the column, such that a downward pressing force applied to the elastic piece (5) by the screw (3) further increases, and the elastic piece (5) then sinks and deforms.

Description

An obstruction detection column and its use method Technical Field

[0001] The present invention relates to the field of furniture, and in particular to an obstruction detection column and a use method thereof. Background Art

[0002] As the concepts of healthy living and healthy work are put forward, ergonomic furniture is becoming more and more popular in our daily life and office, including height-adjustable tables. The emergence of height-adjustable tables has freed people’s working postures from restrictions. Not only can people sit on chairs to work as usual, but they can also stand up to work when they feel uncomfortable from sitting for a long time. This effectively reduces the health problems caused by long-term sitting for people who use desktops for office work.

[0003] For a lifting table driven by dual motors, it generally includes a table top, a crossbeam, and retractable table legs on both sides. The crossbeam is installed under the table top, and the table legs are installed at the left and right ends of the crossbeam. When the table legs are retracted and extended by the motor, the table top also rises and falls accordingly; the table legs include two socketed columns, and a screw transmission mechanism is installed inside the columns. The screw transmission mechanism includes a screw connected to the motor and a square tube threadedly connected to the screw. The motor drives the screw transmission mechanism to realize the telescopic movement.

[0004] The motor drives the table legs to move, and the table legs drive the table top to rise and fall. The lifting movement of the table top is linear. In the actual use of the lifting table, it cannot be guaranteed that the space above and below the lifting table is empty. In other words, the lifting table will encounter obstructions or obstacles during movement. On the one hand, it will cause damage to the motor or transmission mechanism of the lifting table, and on the other hand, it will cause damage to the obstacles, and even pose a safety hazard to users or children. Therefore, the lifting table's retraction function when encountering obstacles is particularly important.

[0005] In existing products, the methods of resistance detection are generally to use current detection, gyroscope detection or sensor detection. When the sensor detects resistance, the sensor needs to collect the deformation amount to convert it into an electrical signal for resistance detection. The key point is how to enhance the deformation capability for sensitive detection. Technical issues

[0006] In order to solve the above technical problems, the present invention provides an resistance detection column, including a motor box and a telescopic support assembly, the connecting piece at the upper end of the telescopic support assembly is connected to the motor box by a screw, and the screw installs an elastic sheet on the step portion of the connecting piece and then locks it to the motor box; a deformation space is formed on the step portion around the screw, and a sensing sheet is provided on the elastic sheet to detect resistance; when the load of the column increases, the downward force applied to the elastic sheet by the screw increases, and the elastic sheet produces a deformation with a downward bending concave center in the deformation space and deforms and sinks as the load increases. Similarly, when the column encounters resistance, the force of the screw on the elastic sheet changes, and the elastic sheet deforms in the deformation space, and the sensing sheet collects the deformation amount of the elastic sheet; the sensing sheet is provided on the elastic sheet, the elastic sheet has good elasticity, and its deformation ability is better than that of components such as the motor box and the bearing fixing plate, making resistance detection more sensitive.

[0007] A method for using the column is further provided, and the steps include assembly, loading, and resistance detection after loading. First, the connecting parts, elastic sheets, screws, and induction sheets are installed in the motor box, and the screws are used to apply a pre-tightening force to the elastic sheets so that the elastic sheets have an initial deformation; when encountering resistance at this time, the screws can drive the elastic sheets to have deformation in both the upper and lower directions, thereby realizing bidirectional deformation when encountering resistance; then the load of the column is increased, so that the downward pressure of the screws on the elastic sheet is further increased, and the elastic sheet sinks and deforms, and at this time it can still have the function of resistance detection, thereby realizing the resistance detection function of the column under load. Technical Solutions

[0008] The technical solution of the present invention is achieved as follows:

[0009] A resistance detection column includes a motor box and a telescopic support assembly. The upper end of the telescopic support assembly is provided with a connecting piece, which is connected to the motor box by a screw; the connecting piece has a step portion, the center of the step portion has a hole and is used to install the screw; an elastic sheet is provided on the step portion, the elastic sheet is located between the step portion and the screw, and a deformation space is formed on the step portion around the screw; the elastic sheet and the step portion are configured such that when the load of the column increases, the downward force applied to the elastic sheet by the screw increases, and the elastic sheet generates a deformation with the center of the elastic sheet bending downward in the deformation space and deforms and sinks as the load increases; an induction sheet is provided on the elastic sheet, and the induction sheet is configured to convert the deformation of the elastic sheet into an electrical signal for judging the resistance situation.

[0010] When the column encounters resistance, the force of the screw on the elastic sheet changes, and the elastic sheet deforms in the deformation space. The sensor sheet collects the deformation of the elastic sheet. The sensor sheet is set on the elastic sheet. The elastic sheet has good elasticity and its deformation ability is better than that of components such as the motor box and the bearing fixing plate, making resistance detection more sensitive.

[0011] Preferably, the stepped portion includes 1-5 steps. The number of steps in the stepped portion can be selected to meet different usage requirements. A single step can solve the problem of resistance detection sensitivity, while multiple steps can solve the problem of preventing the elastic piece from permanently creeping under heavy loads and reducing detection sensitivity.

[0012] Preferably, the step portion includes a first step, a second step and a third step, and the heights of the first step, the second step and the third step decrease in sequence and their diameters decrease in sequence; a first deformation space is formed on the inner side of the first step, a second deformation space is formed on the inner side of the second step, and a third deformation space is formed on the inner side of the third step; the elastic sheet has an initial state, and in the initial state, the elastic sheet abuts against the first step; when the load of the column increases, the downward force applied by the screw to the elastic sheet increases, and the elastic sheet produces a deformation with a downward bending concave center and comes into contact with the second step and the third step as the load increases; when the elastic sheet contacts the first step and bends downward, the elastic sheet deforms in the first deformation space; when the elastic sheet contacts the second step and bends downward, the elastic sheet deforms in the second deformation space; when the elastic sheet contacts the third step, the elastic sheet deforms in the third deformation space.

[0013] The step portion is recessed multiple times from the outside to the inside to form the first step, the second step and the third step; in the initial state, the elastic sheet is only in contact with the first step, and the deformation radius of the elastic sheet is the inner radius of the first step; when the load on the desktop gradually increases, the downward load of the table board and the motor box increases, and the connector is restricted by the bearing on the screw rod to remain stable and fixed and cannot move downward. The screw has a downward load force under the action of the motor box, and the elastic sheet is affected by the screw, resulting in a downward concave deformation in the center. As the load force of the screw increases, after a certain degree of deformation, the elastic sheet contacts the second step, and its deformation radius is the second step. The inner radius of the circle; further increasing the desktop load, the elastic piece further deforms and contacts the third step, and its deformation radius is the inner radius of the third step; when the elastic piece gradually changes from contact with the first step to contact with the third step, the deformation radius of the elastic piece also decreases, the elasticity of the elastic piece becomes harder, and the bearing capacity is stronger, so it can maintain normal operation under large load conditions. Moreover, under large load conditions, the elastic piece can still produce deformation to provide the sensing piece with resistance detection, thereby ensuring the effective operation of the resistance detection function. This solution can realize resistance detection under large loads at a low cost, thereby increasing the working stability of the resistance detection function.

[0014] The larger the deformation radius of the elastic sheet, the larger the part of the elastic sheet that can be deformed or the area that can be deformed, the softer the elasticity of the elastic sheet, the easier it is to deform, and it cannot provide a sufficiently large load-bearing capacity. When the elastic sheet is subjected to an excessive load and cannot be further deformed, the sensor sheet loses the function of detecting resistance, making the lifting table a safety hazard when it is raised or lowered. The step portion in this solution prevents the elastic sheet from always being in a large radius deformation state, thereby preventing the elastic sheet from producing permanent creep, which weakens or loses the effect of detecting resistance. The size of the radius determines the size of the lever arm. When the load is the same, the larger the lever arm, the greater the torque, the greater the elastic force required to resist the torque, and the elastic sheet needs to deform more. The smaller the lever arm, the smaller the torque, and the smaller the deformation of the elastic sheet. Reducing the lever arm prevents the elastic sheet from being excessively deformed and damaged or producing permanent creep under large loads, while ensuring detection sensitivity and extending the service life, ensuring that the resistance detection function is stable and effective.

[0015] Preferably, the first step, the second step, and the third step are all annular, and are arranged from the outside to the inside, with their heights decreasing in sequence. The step portion forms the first step, the second step, and the third step by intermittently decreasing in height. When the elastic sheet bends and sinks inward, it can sequentially contact the first step, the second step, and the third step without causing the elastic sheet to be unsupported and deform over a large area when sinking inward. This prevents creep of the elastic sheet, which could affect the effectiveness of resistance detection.

[0016] Preferably, a first avoidance hole is formed at the center of the step portion, and a second avoidance hole is formed at the center of the elastic sheet; a screw is passed through the first avoidance hole and the second avoidance hole and then connected to the motor box. The screw has the function of connecting the connecting member to the motor box and also acting on the elastic sheet. Therefore, the second avoidance hole is formed on the elastic sheet to allow the screw to act on the elastic sheet, and the first avoidance hole is formed on the step portion to allow the screw to pass through the elastic sheet and the step portion to connect to the motor box.

[0017] Preferably, the screw has a head, the head of the screw downwardly abutting against the elastic sheet. The diameter of the screw head is larger than the second avoidance hole of the elastic sheet, so that the screw contacts the elastic sheet, and when the load is increased or resistance is encountered, the screw acts on the elastic sheet to cause the elastic sheet to deform.

[0018] Preferably, the second avoidance hole on the elastic sheet has a smaller diameter than the first avoidance hole on the step portion. A portion of the elastic sheet is located in the first avoidance hole, so that when the elastic sheet contacts the third step, the elastic sheet can continue to deform downward without affecting the resistance detection function at this time.

[0019] Preferably, the connector is mounted inside the motor box; a connector seat protruding upward is provided inside the motor box, and the connector seat is disposed in the first avoidance hole. The upward protrusion of the connector seat provides more contact when the screw is connected to the motor box, thereby making the connection between the screw and the motor box more stable.

[0020] Preferably, the sensing sheet is in the shape of a circular ring, which is adhered to the elastic sheet and covers the circumference of the elastic sheet. Such a sensing sheet can keenly detect deformation at any position on the elastic sheet.

[0021] Preferably, the sensing piece is in the shape of a disc and is located beside the screw. The disc-shaped sensing piece has a low cost and can also detect the deformation of the elastic piece.

[0022] Preferably, the sensing sheet is adhered to the elastic sheet.

[0023] Preferably, the connecting portion extends downward to form a mounting portion, in which a bearing is installed; the telescopic support assembly further comprises a screw rod, and the bearing is arranged at the upper end portion of the screw rod and is tightly connected to the screw rod.

[0024] A method for using an obstruction detection column:

[0025] S1 Assembly: Place the connector in the motor box, place the elastic sheet in the step, and then screw through the elastic sheet and the step to tighten it to the motor box. Use the screw to apply a pre-tightening force to the elastic sheet, and make the elastic sheet have an initial deformation. At this time, the elastic sheet contacts the step, and the deformation radius of the elastic sheet is the inner radius of the step. Place the induction sheet on the elastic sheet.

[0026] S2 loading: Increase the load on the column so that the downward pressure exerted by the screw on the elastic sheet is greater than the pre-tightening force. The elastic sheet will have an indentation greater than the initial deformation and sink as the load increases.

[0027] First, install the connecting parts, elastic sheets, screws and induction sheets into the motor box, and use the screws to apply pre-tightening force to the elastic sheets so that the elastic sheets have an initial deformation; when encountering resistance at this time, the screws can drive the elastic sheets to deform in both the up and down directions, thereby realizing bidirectional deformation when encountering resistance; then increase the load on the column to further increase the downward pressure of the screws on the elastic sheet, and the elastic sheet sinks and deforms. At this time, it can still have the function of detecting resistance, thereby realizing the resistance detection function of the column under load.

[0028] Preferably, the step portion includes a first step, a second step and a third step; in step S2, as the load increases, the elastic sheet contacts the second step and the third step in sequence; the elastic sheet has three states:

[0029] S2-1 First loading state: After the load on the column increases, the elastic sheet contacts the first step and separates from the second and third steps; the deformation radius of the elastic sheet remains the inner radius of the first step;

[0030] S2-2 Second loading state: After the load on the column increases, the elastic sheet contacts the second step and separates from the third step; the deformation radius of the elastic sheet decreases to the same as the inner radius of the second step;

[0031] S2-3 third loading state: after the load on the column increases, the elastic sheet contacts the third step; the deformation radius of the elastic sheet decreases to the same as the inner radius of the third step;

[0032] S3 Resistance detection after loading: The sensor piece detects the relative deformation of the elastic piece in the above three states and transmits the converted signal to the control unit, which controls the motor to stop and reverse rotation.

[0033] In step S1, the screw applies a pre-tightening force to the elastic sheet, and the elastic sheet has an initial deformation, and the head of the screw is only located above the elastic sheet. At this time, when the table top encounters resistance below, the elastic sheet will have a tendency to recover the deformation due to the upward movement of the screw head due to its initial deformation. After being captured by the sensing sheet, this trend can still be used as a signal to judge resistance, thereby realizing bidirectional resistance detection; similarly, in the second loading state and the third loading state, the elastic sheet is already under pressure and has elastic deformation. When encountering resistance below, a relative deformation will also be generated when the deformation recovers, and the sensing sheet can also realize detection.

[0034] In step S3, the sensing sheet will perform resistance detection on the elastic sheet in three states. In the three states, the deformation radius of the elastic sheet is the inner circle radius of the first step, the inner circle radius of the second step and the inner circle radius of the third step respectively. The deformation radius of the elastic sheet decreases successively, and the part of the elastic sheet that can be deformed also decreases. It has been achieved that the elastic sheet has a smaller deformation radius and deformable part under a larger load, thereby preventing creep and being able to stably and effectively perform resistance detection under different load conditions.

[0035] Preferably, in step S3, the state of the elastic sheet is determined by detecting the absolute deformation continuously maintained by the elastic sheet through the sensing sheet. For the first loading state, the second loading state and the third loading state, the control unit is provided with three corresponding different deformation ranges. When the column is in the lifting process, the sensing sheet gives priority to judging the state of the elastic sheet and compares the relative deformation subsequently generated by the elastic sheet with the corresponding deformation range. When the sensing sheet detects a relative deformation exceeding the corresponding deformation range, the control unit determines that the column is blocked, and the control unit controls the motor to stop and reverse rotation. The above-mentioned absolute deformation refers to the total deformation generated by the elastic member from the undeformed state to the current deformation; the relative deformation refers to the deformation generated when the elastic sheet is deformed after loading and is in the first loading state, the second loading state or the third loading state, and the elastic sheet is deformed again; the deformation range refers to when the relative deformation generated by the elastic sheet exceeds the deformation range, it will be determined to be blocked.

[0036] Preferably, in step S3, the control unit is provided with a first judgment range, a second judgment range and a third judgment range corresponding to the first loading state, the second loading state and the third loading state, the first judgment range is smaller than the second judgment range, and the second judgment range is smaller than the third judgment range; the control unit is also provided with a first deformation range, a second deformation range and a third deformation range corresponding to the first loading state, the second loading state and the third loading state, the first deformation range is larger than the second deformation range, and the second deformation range is larger than the third deformation range. The judgment range is to judge whether the elastic sheet belongs to the first loading state, the second loading state or the third loading state according to the current absolute deformation of the elastic sheet; the deformation range is to judge the resistance of the column according to the relative deformation generated by the elastic sheet; therefore, the first judgment range, the second judgment range and the third judgment range are increased in sequence, and different deformation ranges all start from zero; in different states, the deformation capacity of the elastic sheet is different. If the same deformation range is used to judge the resistance, it will not be accurate enough. As the elastic sheet is in the first, second and third loading states, the deformation capacity of the elastic sheet weakens, and the deformation range should be reduced accordingly to ensure sensitive resistance detection in different states, that is, effective resistance detection capability can be achieved even under larger loads.

[0037] Preferably, step S3 includes:

[0038] S3-1 Resistance detection in the first loading state: After loading, the sensor detects the absolute deformation of the elastic sheet. When the absolute deformation of the elastic sheet at this time is within the first determination range, the elastic sheet is determined to be in the first loading state. When the column is raised or lowered, if the sensor detects that the elastic sheet has deformed and the relative deformation exceeds the first deformation range, the control unit controls the motor to stop and reverse rotation.

[0039] S3-2 Resistance detection in the second loading state: After loading, the sensor detects the absolute deformation of the elastic sheet. When the absolute deformation of the elastic sheet at this time is within the second determination range, the elastic sheet is determined to be in the second loading state. When the column is raised or lowered, if the sensor detects that the elastic sheet has deformed and the relative deformation exceeds the second deformation range, the control unit controls the motor to stop and reverse rotation.

[0040] S3-3 Resistance detection in the third loading state: After loading, the sensing piece detects the absolute deformation of the elastic piece. When the absolute deformation of the elastic piece at this time is within the third determination range, the elastic piece is determined to be in the third loading state; when the column is raised or lowered, the sensing piece detects that the elastic piece has been deformed and the relative deformation exceeds the third deformation range, the control unit controls the motor to stop and rotate in the opposite direction. Beneficial effects

[0041] The design starting point, concept and beneficial effects of the present invention using the above technical solution are:

[0042] When the column encounters resistance, the force of the screw on the elastic sheet changes, and the elastic sheet deforms in the deformation space. The sensor sheet collects the deformation of the elastic sheet. The sensor sheet is set on the elastic sheet. The elastic sheet has good elasticity and its deformation ability is better than that of components such as the motor box and the bearing fixing plate, making resistance detection more sensitive.

[0043] Furthermore, the step portion is recessed multiple times from the outside to the inside to form a first step, a second step and a third step; in the initial state, the elastic sheet is only in contact with the first step, and at this time the deformation radius of the elastic sheet is the inner circle radius of the first step; when the load on the desktop gradually increases, the downward load of the desktop and the motor box increases, and the connector is restricted by the bearing on the screw rod to remain stable and fixed and cannot move downward. The screw has a downward load force under the action of the motor box, and the elastic sheet is affected by the screw, resulting in a deformation with the center concave downward. As the load force of the screw increases, after a certain degree of deformation, the elastic sheet contacts the second step, and its deformation radius is the third step. The inner radius of the second step; further increasing the desktop load, the elastic sheet further deforms and contacts the third step, and its deformation radius is the inner radius of the third step; when the elastic sheet gradually changes from contact with the first step to contact with the third step, the deformation radius of the elastic sheet also decreases, the elasticity of the elastic sheet becomes harder, and the bearing capacity is stronger, so it can maintain normal operation under large load conditions, and under large load conditions, the elastic sheet can still deform for the sensing sheet to perform resistance detection, thereby ensuring the effective operation of the resistance detection function. This solution can realize resistance detection under large loads at a low cost, thereby increasing the working stability of the resistance detection function.

[0044] The larger the deformation radius of the elastic sheet, the larger the part of the elastic sheet that can be deformed or the area that can be deformed, the softer the elasticity of the elastic sheet, the easier it is to deform, and it cannot provide a sufficiently large load-bearing capacity. When the elastic sheet is subjected to an excessive load and cannot be further deformed, the sensor sheet loses the function of detecting resistance, making the lifting table a safety hazard when it is raised or lowered. The step portion in this solution prevents the elastic sheet from always being in a large radius deformation state, thereby preventing the elastic sheet from producing permanent creep, which weakens or loses the effect of detecting resistance. The size of the radius determines the size of the lever arm. When the load is the same, the larger the lever arm, the greater the torque, the greater the elastic force required to resist the torque, and the elastic sheet needs to deform more. The smaller the lever arm, the smaller the torque, and the smaller the deformation of the elastic sheet. Reducing the lever arm prevents the elastic sheet from being excessively deformed and damaged or producing permanent creep under large loads, while ensuring detection sensitivity and extending the service life, ensuring that the resistance detection function is stable and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIG1 is a schematic diagram of the three-dimensional structure of the column in an embodiment of the present invention;

[0046] FIG2 is a three-dimensional cross-sectional view of the column in an embodiment of the present invention;

[0047] FIG3 is an exploded view of the connector, elastic sheet, and inductive sheet disposed inside the motor box in an embodiment of the present invention;

[0048] FIG4 is a three-dimensional cross-sectional view of the connecting member, the elastic sheet and the inductive sheet arranged inside the motor box in an embodiment of the present invention;

[0049] FIG5 is a cross-sectional view of the connecting member, the elastic sheet and the induction sheet arranged inside the motor box in an embodiment of the present invention;

[0050] FIG6 is an exploded view of the internal structure of the motor box in the column in an embodiment of the present invention;

[0051] FIG7 is a flow chart of a method for using the column in an embodiment of the present invention.

[0052] The figures are marked as follows: motor box 1; connecting part 2; screw 3; step portion 4; first step 41; second step 42; third step 43; elastic sheet 5; induction sheet 6; inner tube 7; screw shaft head 9; bearing 10; mounting portion 11; motor 12; first avoidance hole 13; second avoidance hole 14; connecting seat 15; first deformation space 16; second deformation space 17; third deformation space 18. Modes for Carrying Out the Invention

[0053] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0054] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0055] In the description of the present invention, the terms "first", "second", "third", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0056] The specific implementation of the present invention is as follows:

[0057] As shown in Figures 1-3, the present invention provides an resistance detection column, including a motor 12 box 1 and a telescopic support assembly, the upper end of the telescopic support assembly is provided with a connecting piece 2, and the connecting piece 2 is connected to the motor 12 box 1 by a screw 3; the connecting piece 2 includes a step portion 4, and the step portion 4 includes 1-5 steps. Different numbers of steps in the step portion 4 can be selected in different occasions with different usage requirements. A single step can solve the problem of resistance detection sensitivity, and multiple steps can solve the problem of preventing the elastic sheet from permanently creeping and reducing the detection sensitivity under a large load; in this embodiment, the step portion 4 has multiple steps, and the step portion 4 includes a first step 41, a second step 42 and a third step 43. The heights of the first step 41, the second step 42 and the third step 43 decrease in sequence and the diameters of the three decrease in sequence. The center of the step portion 4 is opened and used to install the screw 3; an elastic sheet 5 is provided on the step portion 4, and the elastic sheet 5 is located between the step portion 4 and the screw 3, and a first deformation space 1 is formed inside the first step 41 6, a second deformation space 17 is formed inside the second step 42, and a third deformation space 18 is formed inside the third step 43; the elastic piece 5 has an initial state, in which the elastic piece 5 abuts against the first step 41; the elastic piece 5 has an initial state, in which the elastic piece 5 abuts against the first step 41; the elastic piece 5 and the step portion 4 are configured so that when the load of the column increases, the downward force exerted by the screw 3 on the elastic piece 5 increases, and the elastic piece 5 generates a deformation with the center of the elastic piece being bent downward and concave and deforms as the load increases. The elastic sheet 5 contacts the second step 42 and the third step 43 in turn; when the elastic sheet 5 contacts the first step 41 and bends downward, the elastic sheet 5 is deformed in the first deformation space 16; when the elastic sheet 5 contacts the second step 42 and bends downward, the elastic sheet 5 is deformed in the second deformation space 17; when the elastic sheet 5 contacts the third step 43, the elastic sheet 5 is deformed in the third deformation space 18; a sensing sheet 6 is provided on the elastic sheet 5, and the sensing sheet 6 is configured to convert the deformation of the elastic sheet 5 into an electrical signal for judging the resistance situation.

[0058] The step portion 4 is recessed multiple times from the outside to the inside to form a first step 41, a second step 42 and a third step 43; in the initial state, the elastic sheet 5 is only in contact with the first step 41, and at this time the deformation radius of the elastic sheet 5 is the inner radius of the first step 41; when the load on the desktop gradually increases, the downward load of the desktop and the motor 12 box 1 increases, and the connector 2 is restricted by the bearing 10 on the screw rod to remain stable and fixed and cannot move downward. The screw 3 is subjected to a downward load force by the motor 12 box 1, and the elastic sheet 5 is affected by the screw 3, resulting in a deformation with the center concave downward. As the load force of the screw 3 increases, after a certain degree of deformation occurs, the elastic sheet 5 contacts the second step 42, and its deformation The radius is the inner radius of the second step 42; further increasing the desktop load, the elastic sheet 5 is further deformed and contacts the third step 43, and its deformation radius is the inner radius of the third step 43; when the elastic sheet 5 gradually changes from contacting the first step 41 to contacting the third step 43, the deformation radius of the elastic sheet 5 also decreases, the elasticity of the elastic sheet 5 becomes harder, and the bearing capacity is stronger, and it can maintain normal operation under large load conditions. Moreover, under large load conditions, the elastic sheet 5 can still be deformed for the sensing sheet 6 to perform resistance detection, thereby ensuring the effective implementation of the resistance detection function. This solution can realize resistance detection under large loads at a low cost, thereby increasing the working stability of the resistance detection function.

[0059] The larger the deformation radius of the elastic sheet 5, the larger the part of the elastic sheet 5 that can be deformed or the area that can be deformed, the softer the elasticity of the elastic sheet 5, the easier it is to deform, and it cannot provide a sufficiently large load-bearing capacity. When the elastic sheet 5 is subjected to an excessive load and cannot be further deformed, the sensor sheet 6 loses the function of detecting resistance, making the lifting table a safety hazard when it is raised or lowered. The step portion 4 in this solution prevents the elastic sheet 5 from always being in a large radius deformation state, thereby preventing the elastic sheet 5 from producing permanent creep, which weakens or loses the effect of detecting resistance. The size of the radius determines the size of the lever arm. When the load is the same, the larger the lever arm, the greater the torque, the greater the elastic force required to resist the torque, and the elastic sheet 5 needs to deform more. The smaller the lever arm, the smaller the torque, and the smaller the deformation of the elastic sheet 5. Reducing the lever arm prevents the elastic sheet 5 from being excessively deformed and damaged or producing permanent creep under a large load, while ensuring detection sensitivity and extending the service life, ensuring that the resistance detection function is stable and effective.

[0060] The key point of this column is that its resistance detection function can adapt to large loads and has effective resistance detection capabilities over a larger load range.

[0061] The realization of encountering resistance is as follows: the elastic sheet 5 and the sensor sheet 6 are pressed on the connecting part 2 through the screw 3. When there is a load change, the force is transmitted to the screw 3 and the elastic sheet 5 through the connecting part 2, and the elastic sheet 5 is deformed and the signal of the sensor sheet 6 is used to realize retreat when encountering resistance.

[0062] Adapt to a wider load range: The diameter of the elastic sheet 5 is changed by the multiple steps on the connecting part 2 and the deformation of the elastic sheet 5 (the smaller the load-bearing diameter, the harder the elastic sheet 5), so that the elastic sheet 5 will not permanently creep under large loads (similar to the principle of shock absorbers on the chassis of large trucks).

[0063] Specifically, as shown in Figures 1 and 2, the telescopic support assembly also includes a telescopic sleeve, a push rod and a support. The telescopic sleeve includes an inner tube 7 and an outer tube (not shown). The inner tube 7 and the outer tube are sleeved together and slidably matched with each other, and the outer tube is sleeved outside the inner tube 7; the push rod is arranged in the inner tube 7, the lower end of the push rod is fixedly connected to the outer tube, the upper end of the push rod is a screw shaft head 9, and a bearing 10 is fixed on the screw shaft head 9, and the bearing 10 is tightly fitted with the screw shaft head 9; the connecting member 2 extends downward to form a mounting portion 11, and the bearing 10 is installed in the mounting portion 11; the connecting member 2 is located in the motor 12 box 1, and the motor 1212 is also provided in the motor 12 box 1, and the motor 1212 is transmission-connected to the screw shaft head 9.

[0064] As shown in Figure 3-6, a step portion 4 is provided on the connecting parts on both sides of the mounting portion 11. A hole is opened in the center of the step portion 4 to form a first avoidance hole 13. A connecting seat 15 protrudes upward on the bottom plate of the motor 12 box 1. The connecting seat 15 is in the first avoidance hole 13. The connecting seat 15 is used for threaded connection with the screw 3. The connecting seat 15 protrudes upward, providing more contact when the screw 3 is connected to the motor 12 box 1, so that the connection between the screw 3 and the motor 12 box 1 is more stable.

[0065] An elastic sheet 5 is placed on each of the two step portions 4, and a second avoidance hole 14 is formed in the center of the elastic sheet 5. The screw 3 passes through the first avoidance hole 13 and the second avoidance hole 14 and is connected to the connecting seat 15 of the motor 12 box 1; the screw 3 not only has the function of connecting the connecting part 2 and the motor 12 box 1, but also has the function of acting on the elastic sheet 5. Therefore, a second avoidance hole 14 is opened on the elastic sheet 5 to enable the screw 3 to act on the elastic sheet 5, and a first avoidance hole 13 is opened on the step portion 4 to allow the screw 3 to pass through the elastic sheet 5 and the step portion 4 to be connected to the motor 12 box 1; the screw 3 has a head, and the head of the screw 3 is downwardly abutted on the elastic sheet 5; the diameter of the head of the screw 3 is larger than the second avoidance hole 14 of the elastic sheet 5, so that the screw 3 contacts the elastic sheet 5, so that when the load is increased or resistance is encountered, the screw 3 acts on the elastic sheet 5 to cause the elastic sheet 5 to deform.

[0066] In addition, the aperture of the second avoidance hole 14 on the elastic sheet 5 is smaller than the aperture of the first avoidance hole 13 on the step portion 4; a part of the elastic sheet 5 is located in the first avoidance hole 13, so that when the elastic sheet 5 contacts the third step 43, the elastic sheet 5 can still continue to deform downward and will not affect the resistance detection function at this time.

[0067] The sensing piece 6 is a piezoelectric piece or a strain gauge, which can be in various shapes, the more common ones being circular pieces or annular pieces. The circular piece-shaped sensing piece 6 has a lower cost and can detect the deformation of the elastic piece 5. It can be directly pasted on the elastic piece 5 next to the screw 3; the annular piece-shaped sensing piece 6 is pasted on the elastic piece 5 and can cover the circumference of the elastic piece 5. Such a sensing piece 6 can sensitively detect the deformation of any position on the elastic piece 5; in order to have better detection sensitivity, the annular piece-shaped sensing piece 6 is selected in this embodiment.

[0068] The first step 41, the second step 42 and the third step 43 are all in the shape of a ring. The first step 41, the second step 42 and the third step 43 are distributed from the outside to the inside, and the heights of the three decrease successively. The step portion 4 forms the first step 41, the second step 42 and the third step 43 by intermittently decreasing the height. When the elastic sheet 5 bends and sinks inward, it can contact the first step 41, the second step 42 and the third step 43 in turn, and there will be no situation where the elastic sheet 5 has no support underneath when sinking in, and the elastic sheet 5 produces a large deformation over a large area, thereby preventing the elastic sheet 5 from creeping and affecting the effect of resistance detection.

[0069] As shown in Figure 7, the method of using the column is as follows:

[0070] S1 assembly: Place the connector 2 in the motor 12 box 1, place the elastic sheet 5 in the step 4, and then use screws 3 to pass through the elastic sheet 5 and the step 4 and lock it with the motor 12 box 1. Use screws 3 to apply a pre-tightening force to the elastic sheet 5, and make the elastic sheet 5 have an initial deformation. At this time, the elastic sheet 5 contacts the first step 41, and the deformation radius of the elastic sheet 5 is the inner radius of the first step 41; set the induction sheet 6 on the elastic sheet 5;

[0071] S2 loading: The load of the column is increased so that the downward force exerted by the screw 3 on the elastic sheet 5 is greater than the preload. The elastic sheet 5 will have an inward deformation greater than the initial deformation and contact the second step 42 and the third step 43 in sequence as the load increases. The elastic sheet 5 has three states:

[0072] S2-1 First loading state: After the load on the column increases, the elastic piece 5 contacts the first step 41 and is separated from the second step 42 and the third step 43; the deformation radius of the elastic piece 5 is still the inner radius of the first step 41;

[0073] S2-2 Second loading state: After the load on the column increases, the elastic piece 5 contacts the second step 42 and separates from the third step 43; the deformation radius of the elastic piece 5 decreases to the same as the inner radius of the second step 42;

[0074] S2-3 third loading state: after the load on the column increases, the elastic piece 5 contacts the third step 43; the deformation radius of the elastic piece 5 decreases to the same as the inner radius of the third step 43;

[0075] S3 Resistance detection after loading: The sensing piece 6 detects the relative deformation of the elastic piece 5 in the above three states, and transmits the converted signal to the control unit, which controls the motor 1212 to stop and rotate in the reverse direction.

[0076] Step S3 further includes:

[0077] S3-1 Resistance Detection in the First Loading State: After loading, the sensing piece 6 detects the absolute deformation of the elastic piece 5. When the absolute deformation of the elastic piece 5 at this time is within the first determination range, the elastic piece 5 is determined to be in the first loading state. When the column is raised or lowered, if the sensing piece 6 detects that the elastic piece 5 has deformed and the relative deformation exceeds the first deformation range, the control unit controls the motor 1212 to stop and reverse rotation.

[0078] S3-2 Resistance Detection in the Second Loading State: After loading, the sensing piece 6 detects the absolute deformation of the elastic piece 5. When the absolute deformation of the elastic piece 5 at this time is within the second determination range, the elastic piece 5 is determined to be in the second loading state. When the column is raised or lowered, if the sensing piece 6 detects that the elastic piece 5 has deformed and the relative deformation exceeds the second deformation range, the control unit controls the motor 1212 to stop and reverse rotation.

[0079] S3-3 Resistance detection in the third loading state: After loading, the sensing piece 6 detects the absolute deformation of the elastic piece 5. When the absolute deformation of the elastic piece 5 at this time is within the third determination range, it is determined that the elastic piece 5 is in the third loading state; when the column is raised or lowered, the sensing piece 6 detects that the elastic piece 5 has been deformed and the relative deformation exceeds the third deformation range, the control unit controls the motor 1212 to stop and rotate in the opposite direction.

[0080] In the initial state, the elastic sheet 5 is not pre-tightened by the screw 3. After being pre-tightened by the screw 3, the elastic sheet 5 is in the first loading state. When the column is loaded, as long as the elastic sheet 5 only contacts the first step 41, the elastic sheet 5 is in the first loading state.

[0081] In step S1, the screw 3 applies a pre-tightening force to the elastic sheet 5, and the elastic sheet 5 has an initial deformation, and the head of the screw 3 is only located above the elastic sheet 5. At this time, when the table top encounters resistance below, the elastic sheet 5 will have a tendency to recover the deformation due to the upward movement of the head of the screw 3 due to its initial deformation. After being captured by the sensing sheet 6, this trend can still be used as a signal for judging resistance, thereby realizing bidirectional resistance detection; similarly, in the second loading state and the third loading state, the elastic sheet 5 is already under pressure and has elastic deformation. When encountering resistance below, a relative deformation amount will also be generated when the deformation recovers, and the sensing sheet 6 can also realize detection.

[0082] In step S3, the sensing sheet 6 will perform resistance detection on the elastic sheet 5 in three states. In the three states, the deformation radius of the elastic sheet 5 is the inner radius of the first step 41, the inner radius of the second step 42 and the inner radius of the third step 43 respectively. The deformation radius of the elastic sheet 5 decreases successively, and the part of the elastic sheet 5 that can be deformed is also reduced. It is achieved that the elastic sheet 5 has a smaller deformation radius and deformable part under a larger load, thereby preventing creep and being able to stably and effectively perform resistance detection under different load conditions.

[0083] Furthermore, in step S, the state of the column is determined by detecting the absolute deformation continuously maintained by the elastic sheet 5 through the sensing sheet 6. For the first loading state, the second loading state and the third loading state, the control unit is provided with three corresponding different deformation ranges. When the column is in the lifting process, the sensing sheet 6 gives priority to judging the state of the elastic sheet 5, and compares the relative deformation subsequently generated by the elastic sheet 5 with the corresponding deformation range. When the sensing sheet 6 detects a relative deformation exceeding the corresponding deformation range, the control unit determines that the column is encountering resistance, and the control unit controls the motor 1212 to stop and rotate in the opposite direction.

[0084] Therefore, in step S3, the control unit is provided with a first judgment range, a second judgment range and a third judgment range corresponding to the first loading state, the second loading state and the third loading state, the first judgment range is smaller than the second judgment range, and the second judgment range is smaller than the third judgment range; the control unit is also provided with a first deformation range, a second deformation range and a third deformation range corresponding to the first loading state, the second loading state and the third loading state, the first deformation range is larger than the second deformation range, and the second deformation range is larger than the third deformation range.

[0085] The above-mentioned absolute deformation refers to the total deformation of the elastic member from the undeformed state to the current deformation; the relative deformation refers to the deformation generated when the elastic sheet 5 is deformed again when it is in the first loading state, the second loading state or the third loading state after loading; the deformation range refers to when the relative deformation generated by the elastic sheet 5 exceeds the deformation range, it will be judged as encountering resistance; the judgment range is to judge whether the elastic sheet 5 belongs to the first loading state, the second loading state or the third loading state according to the current absolute deformation of the elastic sheet 5; the deformation range is to judge whether the elastic sheet 5 belongs to the first loading state, the second loading state or the third loading state according to the current absolute deformation of the elastic sheet 5 The relative deformation amount of the elastic sheet 5 is used to determine the resistance of the column; therefore, the first determination range, the second determination range and the third determination range are increased in sequence, and different deformation ranges all start from zero; in different states, the deformation capacity of the elastic sheet 5 is different. If the same deformation range is used to determine the resistance, it will not be accurate enough. As the elastic sheet 5 is in the first, second, and third loading states, the deformation capacity of the elastic sheet 5 weakens, and the deformation range should be reduced accordingly to ensure sensitive resistance detection in different states, that is, effective resistance detection capability can be achieved even under greater loads.

Claims

1. An obstruction detection column, characterized in that: It includes a motor box and a telescopic support assembly, wherein the upper end of the telescopic support assembly is provided with a connecting piece, and the connecting piece is connected to the motor box by a screw; the connecting piece has a step portion, and a hole is opened in the center of the step portion for installing the screw; an elastic sheet is provided on the step portion, and the elastic sheet is located between the step portion and the screw, and a deformation space is formed on the step portion around the screw; the elastic sheet and the step portion are configured as follows: when the load of the column increases, the downward force applied to the elastic sheet by the screw increases, and the elastic sheet generates a deformation with a downward bending concave center in the deformation space and deforms and sinks as the load increases; an induction sheet is provided on the elastic sheet, and the induction sheet is configured to convert the deformation amount of the elastic sheet into an electrical signal for judging the resistance situation.

2. The obstruction detection column according to claim 1, characterized in that: The step portion includes 1 to 5 steps.

3. The obstruction detection column according to claim 1, characterized in that: The step portion includes a first step, a second step and a third step, the heights of the first step, the second step and the third step are successively reduced and their diameters are successively reduced; a first deformation space is formed on the inner side of the first step, a second deformation space is formed on the inner side of the second step, and a third deformation space is formed on the inner side of the third step; the elastic sheet has an initial state, in which the elastic sheet abuts against the first step; when the load of the column increases, the downward force applied by the screw to the elastic sheet increases, the elastic sheet produces a deformation with a center downward bending concave and contacts the second step and the third step as the load increases; when the elastic sheet contacts the first step and bends downward, the elastic sheet is deformed in the first deformation space; when the elastic sheet contacts the second step and bends downward, the elastic sheet is deformed in the second deformation space; when the elastic sheet contacts the third step, the elastic sheet is deformed in the third deformation space.

4. The obstruction detection column according to claim 3, characterized in that: The first step, the second step and the third step are all in a circular shape. The first step, the second step and the third step are distributed from the outside to the inside, and the heights of the three steps decrease successively.

5. The obstruction detection column according to claim 3, characterized in that: The central part of the step portion is opened to form a first avoidance hole, and the central part of the elastic sheet is opened to form a second avoidance hole; the screw passes through the first avoidance hole and the second avoidance hole and is connected to the motor box.

6. The obstruction detection column according to claim 5, characterized in that: The screw has a head, and the head of the screw abuts against the elastic sheet downwards.

7. The obstruction detection column according to claim 5, characterized in that: The second avoidance hole on the elastic sheet has a smaller aperture than the first avoidance hole on the step portion.

8. The obstruction detection column according to claim 5, characterized in that: The connecting piece is installed inside the motor box; a connecting seat protruding upward is arranged inside the motor box, and the connecting seat is arranged in the first avoidance hole.

9. The obstruction detection column according to claim 1, characterized in that: The induction sheet is in the shape of a circular ring.

10. The obstruction detection column according to claim 1, characterized in that: The induction sheet is in the shape of a disc and is located beside the screw.

11. The obstruction detection column according to claim 1, characterized in that: The sensing sheet is adhered to the elastic sheet.

12. The obstruction detection column according to claim 1, characterized in that: The connecting portion extends downward to form a mounting portion, in which a bearing is mounted; the telescopic support assembly also includes a screw rod, and the bearing is arranged at the upper end of the screw rod and is tightly connected to the screw rod.

13. The method for using the obstruction detection column according to claim 1, characterized in that: S1 assembly: placing the connecting piece in the motor box, placing the elastic sheet in the step portion, and then screwing through the elastic sheet and the step portion to lock it with the motor box, and applying a pre-tightening force to the elastic sheet with the screw, so that the elastic sheet has an initial deformation, and at this time the elastic sheet contacts the step portion, and the deformation radius of the elastic sheet is the inner radius of the step portion; the induction sheet is arranged on the elastic sheet; S2 loading: Increase the load on the column so that the downward pressure applied by the screw on the elastic sheet is greater than the pre-tightening force. The elastic sheet will have an indentation greater than the initial deformation and sink as the load increases.

14. The method of use according to claim 13, characterized in that: The step portion includes a first step, a second step and a third step; in step S2, the second step and the third step are contacted in sequence as the load increases; the elastic sheet has three states: S2-1 first loading state: after the load of the column increases, the elastic sheet contacts the first step and is separated from the second step and the third step; the deformation radius of the elastic sheet is still the inner radius of the first step; S2-2 second loading state: after the load of the column increases, the elastic sheet contacts the second step and separates from the third step; the deformation radius of the elastic sheet decreases to the same as the inner radius of the second step; S2-3 third loading state: after the load on the column increases, the elastic sheet contacts the third step; the deformation radius of the elastic sheet decreases to the same as the inner radius of the third step; S3 Resistance detection after loading: The sensor piece detects the relative deformation of the elastic piece in the above three states, and transmits the converted signal to the control unit, which controls the motor to stop and rotate in the reverse direction.

15. The method of use according to claim 14, characterized in that: In step S3, the state of the elastic sheet is determined by detecting the absolute deformation amount continuously maintained by the elastic sheet through the sensing sheet. For the first loading state, the second loading state and the third loading state, the control unit is provided with three corresponding different deformation ranges; when the column is in the process of lifting and lowering, the sensing sheet preferentially determines the state of the elastic sheet, and compares the relative deformation amount subsequently generated by the elastic sheet with the corresponding deformation range. When the sensing sheet detects the relative deformation amount exceeding the corresponding deformation range, the control unit determines that the column is encountering resistance, and the control unit controls the motor to stop and rotate in the opposite direction.

16. The method of use according to claim 14, characterized in that: In step S3, the control unit is provided with a first judgment range, a second judgment range and a third judgment range corresponding to the first loading state, the second loading state and the third loading state, the first judgment range is smaller than the second judgment range, and the second judgment range is smaller than the third judgment range; the control unit is also provided with a first deformation range, a second deformation range and a third deformation range corresponding to the first loading state, the second loading state and the third loading state, the first deformation range is larger than the second deformation range, and the second deformation range is larger than the third deformation range.

17. The method of use according to claim 16, characterized in that: Step S3 includes: S3-1 Detection of resistance in the first loading state: after loading, the sensing sheet detects the absolute deformation of the elastic sheet. When the absolute deformation of the elastic sheet at this time is within the first determination range, the elastic sheet is determined to be in the first loading state; when the column is raised or lowered, the sensing sheet detects that the elastic sheet has been deformed and the relative deformation exceeds the first deformation range, the control unit controls the motor to stop and rotate in the reverse direction; S3-2 Resistance detection in the second loading state: after loading, the sensing sheet detects the absolute deformation of the elastic sheet. When the absolute deformation of the elastic sheet at this time is within the second determination range, the elastic sheet is determined to be in the second loading state; when the column is raised or lowered, the sensing sheet detects that the elastic sheet has been deformed and the relative deformation exceeds the second deformation range, the control unit controls the motor to stop and rotate in the reverse direction; S3-3 Resistance detection under the third loading state: After loading, the sensing piece detects the absolute deformation of the elastic piece. When the absolute deformation of the elastic piece at this time is within the third determination range, the elastic piece is determined to be in the third loading state. When the column is raised or lowered, the sensing piece detects that the elastic piece has been deformed and the relative deformation exceeds the third deformation range, the control unit controls the motor to stop and rotate in the opposite direction.

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