Structure for bidirectionally detecting obstacle encountering situation at high sensitivity and use method therefor

Abstract

A structure for bidirectionally detecting obstacle encountering at a high sensitivity and a use method therefor. The structure comprises a base (1), wherein the base (1) is provided with an accommodating space (5), a blocking portion (6) is provided at an end portion of the accommodating space (5), and a bearing (2), a detection member (7), a pressure applying member (8), a squeezing member (9), and a limiting member (10) are provided in the accommodating space (5), the detection member (7) and the pressure applying member (8) being located between the blocking portion (6) and the bearing (2), the squeezing member (9) and the limiting member (10) being located on the other side of the bearing (2), and adjacent components abutting against each other; the detection member (7) and the squeezing member (9) are elastic, and the distance between the limiting member (10) and the bearing (2) is less than the thickness of the squeezing member (9), such that the squeezing member (9) is compressed and generates an elastic force, and the elastic force is applied to the detection member (7) by means of the bearing (2) and the pressure applying member (8); the pressure applying member (8) abuts against the detection member (7) and applies a pre-pressure to the detection member (7), such that the detection member (7) is in a pre-deformed state, and when a height-adjustable desk encounters an obstacle, the pressure applied to the detection member (7) by the pressure applying member (8) changes, and the detection member (7) generates a deformation that is different from the pre-deformed state; and a sensing sheet arranged on the detection member (7) converts the amount of deformation of the detection member (7) into a signal and transmits the signal to a control unit used for determining an obstacle encountering situation.

Description

Structure and method for using bidirectional high-sensitivity detection of obstruction Technical Field

[0001] The present invention relates to the technical field of lifting tables, and in particular to a structure for detecting obstructions in both directions with high sensitivity and a method for using the structure. Background Art

[0002] 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.

[0003] However, in the actual use of the lifting table, there is no guarantee 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. 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.

[0004] In existing products, the methods of resistance detection are generally to use current detection, gyroscope detection or sensor detection. When the sensor detection encounters resistance, the setting position of the sensor needs to be considered. The setting position of some sensor plates is not reasonable, which will cause the resistance detection in a certain direction to fail when there is no load or heavy load. There is also the problem of sensitivity, which will affect the detection effect and thus affect the safety of the lifting table during movement. Technical Solutions

[0005] In order to solve the above technical problems, the present invention provides a bidirectional high-sensitivity detection structure for encountering obstacles, including a base, a accommodating space is provided on the base, a blocking portion is provided at the end of the accommodating space, a bearing, a detection member, a pressure member, an extrusion member and a limit member are provided in the accommodating space, the detection member and the pressure member are located between the blocking portion and the bearing, the extrusion member and the limit member are located on the other side of the bearing, and adjacent parts are in contact with each other; the detection member and the extrusion member are elastic, and during installation, the extrusion member is compressed and then the limit member is placed, and the extrusion member is kept in a compressed state by the limit member; the extrusion member gives The bearing exerts elastic force in the direction of the pressure piece, and the bearing and the pressure piece have the ability to float; the bearing presses the pressure piece and gives the pressure piece a force toward the detection piece, the pressure piece presses against the detection piece and applies pre-pressure to the detection piece, the detection piece is in a pre-deformed state, when the lifting table encounters resistance, the pressure piece and the bearing float, the pressure applied to the detection piece by the pressure piece changes, and the detection piece produces a deformation different from the pre-deformed state; the detection piece is provided with a sensor sheet for detecting the deformation amount of the detection piece, and the sensor sheet is configured to convert the deformation amount of the detection piece into a signal and transmit it to a control unit for judging the resistance situation.

[0006] A method for using the structure is further provided, wherein the detection member, the pressure member, the bearing, the extrusion member and the limit member are stacked in sequence in the accommodating space, and the structure is used to connect the motor box and the screw rod; when the table top rises and encounters resistance, the base, the blocking part and the limit member float downward relative to the bearing, the extrusion member is deformed due to the displacement of the limit member, and the detection member is aggravated in deformation by the action of the blocking part and the pressure member, the sensor detects the deformation amount in this process and transmits the converted signal to the control unit, the control unit controls the motor to stop and reverse, so that the table top stops and then descends; when the table top descends and encounters resistance, the base, the blocking part and the limit member float upward relative to the bearing, the extrusion member is deformed due to the displacement of the limit member, and the detection member is weakened in deformation by the action of the blocking part and the pressure member, the sensor detects the deformation amount in this process and transmits the converted signal to the control unit, the control unit controls the motor to stop and reverse, so that the table top stops and then rises.

[0007] The technical solution of the present invention is achieved as follows:

[0008] A structure for bidirectionally and highly sensitively detecting resistance situations comprises a base and a bearing, wherein the base is configured to be connected to a motor box, the bearing is configured to be connected to a screw rod, the base has an accommodating space, and an end portion of the accommodating space is provided with a blocking portion; a detecting member and a pressure member are provided in the accommodating space between the bearing and the blocking portion, and an extrusion member and a limiting member are provided in the accommodating space on the other side of the bearing; the pressure member abuts the bearing, the detecting member is located between the pressure member and the blocking portion, the extrusion member abuts the bearing, the limiting member abuts the extrusion member and is relatively fixedly connected to the base in the axial direction; the detecting member and the extrusion member are elastic, and the limiting member is configured to limit the distance between the limiting member and the bearing to be smaller than the extrusion member. The thickness of the extrusion piece is compressed to generate elastic force; the extrusion piece is configured to give the bearing an elastic force toward the pressure piece, and to enable the bearing and the pressure piece to float; the bearing presses the pressure piece and gives the pressure piece a force toward the detection piece, the pressure piece presses against the detection piece and applies pre-pressure to the detection piece, the detection piece is in a pre-deformed state, when the lifting table encounters resistance, the pressure piece and the bearing float, the pressure applied to the detection piece by the pressure piece changes, and the detection piece produces a deformation different from the pre-deformed state; the detection piece is provided with a sensor sheet for detecting the deformation amount of the detection piece, and the sensor sheet is configured to convert the deformation amount of the detection piece into a signal and transmit it to a control unit for judging the resistance situation.

[0009] The floating ability of the pressure piece and the bearing refers to the floating ability of the pressure piece and the bearing in the base when the lifting table encounters resistance. The floating is relative to the base. In fact, after the table plate encounters resistance, the motor box connected to the table plate and the base connected to the motor box float up and down relative to the screw rod, and the blocking part on the base and the limiter in the base float accordingly. Relative floating occurs between the base, the pressure piece and the bearing. The base is actively floating, and the pressure piece and the bearing are passively floating. The extrusion piece produces corresponding deformation with the floating between the limiter and the bearing, and the detection piece is between the pressure piece and the bearing. Deformation is also generated under the action of the blocking part, which can also be reflected as the relative floating of the pressure piece, the bearing and the base, and the pressure piece squeezing or relaxing the detection piece; that is, when encountering resistance above the table top, the base floats downward, which is equivalent to the bearing and the pressure piece floating upward relative to the detection piece, the pressure piece and the blocking part approach, and the detection piece is squeezed, causing the detection piece to be more deformed relative to the pre-deformed state; when encountering resistance below the table top, the base floats upward, and floats downward relative to the bearing and the pressure piece relative to the detection piece, the pressure piece and the blocking part move away, and the detection piece is relaxed, causing the detection piece to be less deformed relative to the pre-deformed state.

[0010] From a macroscopic perspective, the floating ability brought by the extrusion part causes the floating between the screw and the base, that is, the floating between the motor box and the screw. Therefore, when encountering resistance, the force on the table top changes, destroying the original force balance between the motor box and the screw, resulting in a movement trend between the motor box and the screw. This movement trend can be reflected through the above-mentioned tiny floating. The elastic detection part can amplify this tiny floating and reflect it through its own deformation, thereby judging the situation of encountering resistance.

[0011] Floating will cause the pressure applied by the pressure piece to the detection piece to change and deviate from the pre-pressure, or in other words, the floating of the pressure piece will weaken or aggravate the deformation of the detection piece; when the lifting table encounters resistance, the bearing and the pressure piece will float. Compared with the plate of the motor box, the elastic detection piece will be significantly changed in force, and the deformation detected by the sensor piece will also be more obvious, making the resistance detection more sensitive; this structure is set between the screw rod and the motor box, where the force transmission is relatively direct and the force change is relatively obvious, which can also increase the sensitivity of resistance detection.

[0012] The limiter restricts the distance between the limiter and the bearing to be smaller than the thickness of the extrusion part. In other words, the distance between the limiter and the blocking part is smaller than the sum of the thicknesses of the extrusion part, the bearing, the pressure part and the detection part. The extrusion part with a smaller elastic modulus is deformed first, thereby bringing about floating ability. Having floating ability actually means that the extrusion part always has the ability to elastically deform during normal operation, so that the whole is in an extruded state, ensuring that the pressure part always applies pressure to the detection part, and the detection part is always in a deformed state, so that the detection part can be deformed when the lifting table encounters resistance in the up and down directions.

[0013] The pressure-applying member presses against the detection member and applies pre-pressure to the detection member, and the detection member is in a pre-deformed state; if the pressure-applying member does not apply pre-pressure to the detection member, pressure will be applied to the detection member only when the pressure-applying member moves upward, then only obstacles from above can be detected. If the obstacle comes from below, the pressure applied to the detection member by the pressure-applying member is always zero, and it cannot play the role of detecting obstacles.

[0014] The deformation variable in the pre-deformation state can be set to zero. How to judge the deformation variable and how to judge whether resistance is encountered (acceptable deformation variable range) are determined by the programming of the control unit.

[0015] Preferably, the inner wall of the accommodating space extends inwardly in the radial direction to form the blocking portion, which is annular. The pressure member is annular, and the inner edge of the pressure member protrudes upward to form a pressing portion, which abuts the inner edge of the detection member. The detection member is blocked from top to bottom by the blocking portion. When the pressing portion applies pressure to the detection member from bottom to top, deformation occurs between the inner and outer edges of the detection member. The pressing portion reduces the contact area between the pressure member and the detection member, making the deformation caused by the pressure member on the detection member more obvious, thereby ensuring high sensitivity of resistance detection.

[0016] Preferably, the accommodating space is through-connected from top to bottom, and the blocking portion is arranged at the upper opening of the accommodating space; the detecting member, the pressure member, the bearing, the extrusion member and the limiting member are arranged in the accommodating space in sequence from top to bottom.

[0017] Preferably, the detection piece is in the form of a flat sheet, which makes it easier to attach the sensing sheet.

[0018] Preferably, the detection member is an elastic sheet. The elastic sheet of the thin sheet is more conducive to deformation, thereby making the resistance detection more sensitive.

[0019] Preferably, the limiting member is a clip spring, and the inner wall of the accommodating space is provided with a corresponding annular groove for the clip spring to engage in. Using the clip spring as the limiting member has a simple structure and low cost, and effectively achieves the limiting effect required by the above solution.

[0020] Preferably, the pressure-applying member is a rigid member, which can more effectively and directly transmit and apply pressure to the detection member to ensure the sensitivity of the resistance detection.

[0021] Preferably, the extrusion member is a rubber ring, which has low cost and can effectively achieve the desired effect.

[0022] Preferably, the sensing sheet is a strain gauge or a piezoelectric sheet; the sensing sheet is circular, rectangular, or fan-shaped; the sensing sheet is affixed to the detection member and located adjacent to the lead screw. The sensing sheet can have a variety of shapes, all achieving similar effects. Circular and rectangular sensing sheets are relatively mature in manufacturing and have relatively low material costs, while fan-shaped sensing sheets fit more symmetrically with the annular detection member, increasing the sensitivity of detecting symmetrical forces on the detection member structure and, therefore, increasing the sensitivity of resistance detection. The sensing sheet is located adjacent to the lead screw rather than surrounding it.

[0023] Preferably, the base is provided with a relief hole, which communicates with the accommodating space. The relief hole is configured to provide clearance for the signal line of the sensing plate, allowing the signal line to pass through the base and connect to the control unit. In addition to allowing the signal line to pass through, the relief hole also allows the outer edge of the detection member at the relief hole to remain in a state of suspension, thereby increasing the deformation of the detection member caused by the force, thereby further increasing the sensitivity of the obstruction detection.

[0024] Preferably, the base includes a fixing plate and a mounting portion, the fixing plate being configured to be fixedly connected to the motor box, the mounting portion being located below the fixing plate and protruding downwardly from the bottom of the motor box; an accommodating space is defined in the mounting portion, and when the sensor sheet is disposed on the detection member, the sensor sheet is located below the bottom of the motor box. Compared to the prior art, the sensor sheet is neither mounted on the motor box nor on the base, but is instead located below the motor box and mounted on the elastic detection member. This eliminates the need to reduce the thickness of the motor box or base to increase deformation capacity in order to increase the detection sensitivity of the sensor sheet.

[0025] Preferably, the induction plate is located 0.5-1 cm below the motor box.

[0026] A method for using a structure for bidirectionally and highly sensitively detecting resistance, comprising placing the detection member, pressure member, bearing, extrusion member and limit member in an accommodating space in sequence from top to bottom; installing the structure in a lifting table, fixing the base to a motor box relative to each other, fixing the bearing to a lead screw relative to each other, and connecting the motor box and the lead screw of the lifting table with the structure; when the table top fixedly connected to the motor box in the lifting table moves upward and encounters resistance, the motor box tends to move downward relative to the lead screw, the base and the limit member float downward relative to the bearing, the extrusion member is deformed accordingly, and the detection member tends to move downward relative to the pressure member under the action of the blocking portion, and the relative force between the pressure member and the detection member increases. , the detection part produces a deformation greater than the pre-deformation state, the sensor piece detects the deformation of the detection part in this process and transmits the converted signal to the control unit, the control unit controls the motor of the lifting table to stop and reverse rotation, so that the table top stops and then falls; when the table top moves downward and encounters resistance, the motor box produces a tendency to move upward relative to the screw rod, the base and the limit piece float upward relative to the bearing, the extrusion piece is deformed accordingly, the blocking part floats upward away from the pressure piece, the relative force between the pressure piece and the detection piece is reduced, and the deformation of the detection piece will be smaller than the deformation in the pre-deformation state, the sensor piece detects the deformation of the detection part in this process and transmits the converted signal to the control unit, the control unit controls the motor to stop and reverse rotation, so that the table top stops and then rises.

[0027] When encountering resistance, the bearing and pressure member remain stationary, while the base, stopper, and the blocking portion on the base float relative to them. The extrusion member consistently applies elastic force to the bearing and pressure member. This force varies with the floating of the stopper, but it consistently keeps the pressure member pressed against the detection member, preventing it from disengaging. This also restores the structural components to their original positions after the lift table clears the obstacle. The bearing and pressure member remain stationary, and the pressure member consistently abuts the detection member. As the blocking portion floats with the base, the force exerted by the blocking portion on the detection piece changes, causing the detection member to deform under the combined action of the pressure member and the blocking portion, thereby determining the resistance situation. Beneficial effects

[0028] The design starting point, concept and beneficial effects of the present invention using the above technical solution are:

[0029] The floating ability of the pressure piece and the bearing refers to the floating ability of the pressure piece and the bearing in the base when the lifting table encounters resistance. The floating is relative to the base. In fact, after the table plate encounters resistance, the motor box connected to the table plate and the base connected to the motor box float up and down relative to the screw rod, and the blocking part on the base and the limiter in the base float accordingly. Relative floating occurs between the base, the pressure piece and the bearing. The base is actively floating, and the pressure piece and the bearing are passively floating. The extrusion piece produces corresponding deformation with the floating between the limiter and the bearing, and the detection piece is between the pressure piece and the bearing. Deformation is also generated under the action of the blocking part, which can also be reflected as the relative floating of the pressure piece, the bearing and the base, and the pressure piece squeezing or relaxing the detection piece; that is, when encountering resistance above the table top, the base floats downward, which is equivalent to the bearing and the pressure piece floating upward relative to the detection piece, the pressure piece and the blocking part approach, and the detection piece is squeezed, causing the detection piece to be more deformed relative to the pre-deformed state; when encountering resistance below the table top, the base floats upward, and floats downward relative to the bearing and the pressure piece relative to the detection piece, the pressure piece and the blocking part move away, and the detection piece is relaxed, causing the detection piece to be less deformed relative to the pre-deformed state.

[0030] From a macroscopic perspective, the floating ability brought by the extrusion part causes the floating between the screw and the base, that is, the floating between the motor box and the screw. Therefore, when encountering resistance, the force on the table top changes, destroying the original force balance between the motor box and the screw, resulting in a movement trend between the motor box and the screw. This movement trend can be reflected through the tiny floating in the above structure. The elastic detection part can amplify this tiny floating and reflect it through its own deformation, thereby judging the situation of encountering resistance.

[0031] Floating will cause the pressure applied by the pressure piece to the detection piece to change and deviate from the pre-pressure, or in other words, the floating of the pressure piece will weaken or aggravate the deformation of the detection piece; when the lifting table encounters resistance, the bearing and the pressure piece will float. Compared with the plate of the motor box, the elastic detection piece will be significantly changed in force, and the deformation detected by the sensor piece will also be more obvious, making the resistance detection more sensitive; this structure is set between the screw rod and the motor box, where the force transmission is relatively direct and the force change is relatively obvious, which can also increase the sensitivity of resistance detection.

[0032] Compared with existing products, the structure of the present invention uses lower-cost components, which improves the sensitivity of the lift table's resistance detection in a low-cost manner, thereby minimizing the adverse effects of collisions.

[0033] The limiter restricts the distance between the limiter and the bearing to be smaller than the thickness of the extrusion part. In other words, the distance between the limiter and the blocking part is smaller than the sum of the thicknesses of the extrusion part, the bearing, the pressure part and the detection part. The extrusion part with a smaller elastic modulus is deformed first, thereby bringing about floating ability. Having floating ability actually means that the extrusion part always has the ability to elastically deform during normal operation, so that the whole is in an extruded state, ensuring that the pressure part always applies pressure to the detection part, and the detection part is always in a deformed state, so that the detection part can be deformed when the lifting table encounters resistance in the up and down directions.

[0034] The pressure-applying member presses against the detection member and applies pre-pressure to the detection member, and the detection member is in a pre-deformed state; if the pressure-applying member does not apply pre-pressure to the detection member, pressure will be applied to the detection member only when the pressure-applying member moves upward, then only obstacles from above can be detected. If the obstacle comes from below, the pressure applied to the detection member by the pressure-applying member is always zero, and it cannot play the role of detecting obstacles.

[0035] Compared with existing products, the induction sheet is no longer arranged on the motor box, but is mainly arranged on the base and on the detection part in the base. Specifically, the accommodating space for installing the bearing at the lower part of the base is improved. In addition to the bearing, the accommodating space also has a detection part, a pressure part, an elastic ring and a retaining spring. The detection part and the pressure part are located above the bearing, and the elastic ring and the retaining spring are located below the bearing. The elastic ring is against the bearing. After the retaining spring is snapped into the base to complete the overall installation, the elastic ring is restricted in the up and down directions, and the elastic ring is compressed (caused by the gap between the position where the retaining spring is snapped in and the bearing is smaller than the thickness of the elastic ring), and always gives the bearing an upward elastic force. The circumference is raised upward and pressed against the detection part. The upper part of the outer circumference of the detection part is blocked by the base. The elastic force of the elastic ring will be transmitted to the pressure part, and the pressure part always presses the detection part, giving the detection part pressure to produce a deformation trend. The sensor piece is arranged on the detection part and detects the deformation amount on the detection part, that is, the change in force. Due to the existence of the elastic ring, the bearing and the pressure part can float. When the lifting table encounters resistance, the bearing and the pressure part will float, the force on the detection part will change significantly, and the deformation detected by the sensor piece will also be more obvious, thereby making the resistance detection more sensitive. Moreover, the ability of the bearing and the pressure part to float up and down enables the sensor piece to detect resistance in both the upper and lower directions of the table top.

[0036] The deformation amount in the pre-deformation state can be set to zero point. How to judge the deformation amount and whether resistance is encountered (acceptable deformation amount range) is determined by the program of the control unit.

[0037] When encountering actual resistance, the bearing and the pressure piece are stationary, and the base, the limit piece and the blocking part on the base will float relative to the bearing and the pressure piece. The extrusion piece can always give the bearing and the pressure piece elastic force. The elastic force changes with the floating of the limit piece, but the elastic force always makes the pressure piece press against the detection piece without separating, and can also restore the original position relationship of the various components in the structure after the lifting table leaves the obstacle; the bearing and the pressure piece are stationary, and the pressure piece always abuts the detection piece. When the blocking part floats with the base, the force of the blocking part on the detection piece is changed, and the detection piece is deformed under the joint action of the pressure piece and the blocking part, so as to determine the resistance situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG1 is a schematic diagram of the three-dimensional structure of the lifting column in an embodiment of the present invention;

[0039] FIG2 is a schematic diagram of a three-dimensional structure of a base installed in a motor box in an embodiment of the present invention;

[0040] FIG3 is a cross-sectional view of the lifting column in an embodiment of the present invention;

[0041] FIG4 is an exploded view of the structure in an embodiment of the present invention;

[0042] FIG5 is a second exploded view of the structure in an embodiment of the present invention;

[0043] FIG6 is a top view of the structure in an embodiment of the present invention;

[0044] FIG7 is a cross-sectional view of the structure in an embodiment of the present invention;

[0045] FIG8 is a schematic diagram of a detection member in a pre-deformed state according to an embodiment of the present invention;

[0046] FIG9 is a schematic diagram of an embodiment of the present invention in which the deformation of the detection member is aggravated;

[0047] FIG10 is a schematic diagram showing the weakening of the deformation of the detection member in an embodiment of the present invention.

[0048] The figures are marked as follows: base 1; fixing plate 101; mounting portion 102; bearing 2; motor box 3; screw 4; accommodating space 5; annular groove 51; blocking portion 6; detecting member, elastic sheet 7; pressure member 8; pressing portion 81; extrusion member, rubber ring 9; limiting member, retaining spring 10; sensing sheet 11; telescopic sleeve 12; fixing tube 121; lifting tube 122; push rod 13; avoidance hole 14. Modes for Carrying Out the Invention

[0049] The specific implementation of the present invention is as follows:

[0050] As shown in Figures 3-5, the present invention provides a structure for bidirectionally and highly sensitively detecting resistance, including a base 1 and a bearing 2. The base 1 is configured to be connected to a motor box 3, and the bearing 2 is configured to be connected to a screw rod 4. The base 1 has an accommodating space 5, and a blocking portion 6 is provided at the end of the accommodating space 5; a detecting member 7 and a pressure member 8 are provided in the accommodating space 5 between the bearing 2 and the blocking portion 6, and an extrusion member 9 and a limiting member 10 are provided in the accommodating space 5 on the other side of the bearing 2; the pressure member 8 abuts against the bearing 2, the detecting member 7 is located between the pressure member 8 and the blocking portion 6, the extrusion member 9 abuts against the bearing 2, the limiting member 10 abuts against the extrusion member 9 and is relatively fixedly connected to the base 1 in the axial direction; the detecting member 7 and the extrusion member 9 are elastic, and the limiting member 10 is configured to limit the limiting member 10 and The distance between the bearings 2 is smaller than the thickness of the extrusion piece 9, so that the extrusion piece 9 is compressed to generate elastic force; the extrusion piece 9 is configured to give the bearing 2 an elastic force toward the pressure piece 8, and enable the bearing 2 and the pressure piece 8 to float; the bearing 2 presses the pressure piece 8 and gives the pressure piece 8 a force toward the detection piece 7, the pressure piece 8 presses against the detection piece 7 and applies pre-pressure to the detection piece 7, the detection piece 7 is in a pre-deformed state, when the lifting table encounters resistance, the pressure piece 8 and the bearing 2 float, the pressure applied by the pressure piece 8 to the detection piece 7 changes, and the detection piece 7 produces a deformation different from the pre-deformed state; the detection piece 7 is provided with a sensor sheet 11 for detecting the deformation of the detection piece 7, the sensor sheet 11 is configured to convert the deformation of the detection piece 7 into a signal and transmit it to the control unit for judging the resistance situation.

[0051] Specifically, as shown in Figures 1-3, the structure is set in a lifting table, which includes table legs, table tops and lifting columns. The upper and lower ends of the lifting columns are respectively connected to the table legs and table tops; the lifting columns include a motor box 3, a telescopic sleeve 12 and a push rod 13 set in the telescopic sleeve 12. The push rod 13 is connected to the motor set in the motor box 3 and is driven by the motor to move the push rod 13. The movement of the push rod 13 drives the telescopic sleeve 12 to extend and retract, thereby realizing the lifting of the lifting table. The screw 4 in the push rod 13 is connected to the motor transmission; the motor box 3 is fixedly connected to the table top, and the telescopic sleeve 12 includes a fixed tube 121 fixedly connected to the table legs and a lifting tube 122 fixedly connected to the motor box 3.

[0052] In this structure, the table top, motor box 3, base 1, and lifting tube 122 can be divided into a floating group that is relatively fixed together, while the fixed tube 121, table legs, and push rod 13 can be divided into a fixed group that is relatively fixed together. When the table top encounters resistance and is subjected to force, the floating group and the fixed group can have a tendency to float slightly or relatively float in this structure. The sensor sheet 11 detects structural changes in this structure and gives a signal to the control unit to determine whether there is resistance.

[0053] As shown in Figures 4-7, the base 1 includes a fixing plate 101 and a mounting portion 102. The fixing plate 101 is located above the mounting portion 102 and is fixedly connected to the motor box 3 by screws. The mounting portion 102 protrudes downward from the bottom of the motor box 3. The mounting portion 102 is a vertically arranged hollow cylinder. The accommodating space 5 is opened on the mounting portion 102. The accommodating space 5 passes through the mounting portion 102 from top to bottom. The blocking portion 6 is arranged at the upper opening of the accommodating space 5; an opening communicating with the accommodating space 5 is opened on the fixing plate 101, and the upper end of the screw rod 4 can be located in the accommodating space 5 and the opening; the detecting member 7, pressure member 8, bearing 2, extrusion member 9 and limit member 10 are arranged in the accommodating space 5 in sequence from top to bottom; the detecting member 7 is an elastic sheet 7, and is a flat sheet, the pressure member 8 is a rigid member, the limiting member 10 is a retaining spring 10, and the extrusion member 9 is a rubber ring 9; the flat detection member 7 is easier to stick to the sensing sheet 11, and the thin elastic sheet 7 is more conducive to deformation, thereby making the resistance detection more sensitive; the rigid pressure member 8 can more effectively and directly transmit and give pressure to the detection member 7 to ensure the sensitivity of the resistance detection, the rubber ring 9 has a low cost and can effectively achieve the required effect; the inner wall of the accommodating space 5 corresponds to the retaining spring 10 and is provided with a ring groove 51 for the retaining spring 10 to be inserted, the retaining spring 10 is arranged in the ring groove 51 and is axially fixed relative to the base 1, and the retaining spring 10 is used as the limiting member 10, the structure is simple and the cost is low, and it effectively achieves the limiting effect required by the above scheme.

[0054] Along the radial direction, the inner wall at the upper end opening of the accommodating space 5 extends inward to form the blocking portion 6, and the blocking portion 6 is annular; the pressure piece 8 is annular, and the inner edge of the pressure piece 8 protrudes upward to form a pressing portion 81, and the pressing portion 81 abuts against the inner edge of the detection piece 7; the detection piece 7 is blocked from top to bottom by the blocking portion 6, and when the pressing portion 81 presses the detection piece 7 from bottom to top, deformation occurs between the inner edge and the outer edge of the detection piece 7; the pressing portion 81 reduces the contact area between the pressure piece 8 and the detection piece 7, making the deformation caused by the pressure piece 8 on the detection piece 7 more obvious, thereby ensuring high sensitivity of resistance detection.

[0055] The induction sheet 11 is circular, rectangular or fan-shaped, and there are many shapes of the induction sheet 11, all of which can achieve similar effects. Among them, the circular and rectangular induction sheets 11 have relatively mature processes and relatively low material costs, while the fan-shaped induction sheet 11 fits the annular detection piece 7 more symmetrically, increasing the sensitivity of detecting the symmetrical force of the detection piece 7 structure, thereby increasing the sensitivity of resistance detection. When the induction sheet 11 is set on the detection piece 7, it is located 0.5-1 cm below the bottom of the motor box 3. The induction sheet 11 is neither installed on the motor box 3 nor on the base 1, but is located below the motor box 3 and is arranged on the elastic detection piece 7. There is no need to reduce the thickness of the motor box 3 or the base 1 to increase the deformation capacity in order to increase the detection sensitivity of the induction sheet 11.

[0056] The base 1 is provided with a relief hole 14, which communicates with the accommodating space 5. This relief hole 14 is configured to provide clearance for the signal line of the sensing plate 11, allowing the signal line to pass through the base 1 and connect to the control unit. Besides allowing the signal line to pass through, the relief hole 14 also allows the outer edge of the detection member 7 at the location of the relief hole 14 to remain free. This increases the deformation of the detection member 7 under stress, thereby further increasing the sensitivity of the obstruction detection.

[0057] The floating ability of the pressure piece 8 and the bearing 2 refers to the floating ability of the pressure piece 8 and the bearing 2 in the base 1 when the lifting table encounters resistance. The floating is relative to the base 1. In fact, after the table top encounters resistance, the motor box 3 connected to the table top and the base 1 connected to the motor box 3 float up and down relative to the screw rod 4, and the blocking part 6 on the base 1 and the limiter 10 in the base 1 float accordingly. Relative floating occurs between the base 1 and the pressure piece 8 and the bearing 2. The base 1 is actively floating, and the pressure piece 8 and the bearing 2 are passively floating. The extrusion piece 9 produces corresponding deformation with the floating between the limiter 10 and the bearing 2, and the detection piece 7 is on the pressure piece. 8 also produces deformation under the action of the blocking part 6, which can also be reflected as the pressure piece 8, the bearing 2 and the base 1 floating relative to each other, and the pressure piece 8 squeezing or relaxing the detection piece 7; that is, when encountering resistance above the table top, the base 1 floats downward, which is equivalent to the bearing 2 and the pressure piece 8 floating upward relative to the detection piece 7, the pressure piece 8 and the blocking part 6 are close, and the detection piece 7 is squeezed, so that the deformation of the detection piece 7 is aggravated relative to the pre-deformation state; when encountering resistance below the table top, the base 1 floats upward, and floats downward relative to the bearing 2 and the pressure piece 8 relative to the detection piece 7, the pressure piece 8 and the blocking part 6 are away, and the detection piece 7 is relaxed, so that the deformation of the detection piece 7 is weakened relative to the pre-deformation state.

[0058] From a macroscopic perspective, the floating ability brought by the extrusion part 9 causes the floating between the screw rod 4 and the base 1, that is, the floating between the motor box 3 and the screw rod 4. Therefore, when encountering resistance, the force on the table top changes, destroying the original force balance between the motor box 3 and the screw rod 4, resulting in a movement trend between the motor box 3 and the screw rod 4. This movement trend can be reflected through the above-mentioned tiny floating. The elastic detection part 7 can amplify this tiny floating and reflect it through its own deformation, thereby judging the situation of encountering resistance.

[0059] Floating will cause the pressure exerted by the pressure member 8 on the detection member 7 to change and deviate from the pre-pressure, or in other words, the floating of the pressure member 8 will weaken or aggravate the deformation of the detection member 7; when the lifting table encounters resistance, the bearing 2 and the pressure member 8 will float. Compared with the plate of the motor box 3, the elastic detection member 7 is significantly changed in force, and the deformation detected by the sensor sheet 11 is also more obvious, thereby making the resistance detection more sensitive; this structure is arranged between the screw rod 4 and the motor box 3, where the force transmission is relatively direct and the force change is relatively obvious, which can also increase the sensitivity of resistance detection.

[0060] Compared with existing products, the structure of the present invention uses lower-cost components, which improves the sensitivity of the lift table's resistance detection in a low-cost manner, thereby minimizing the adverse effects of collisions.

[0061] The limit member 10 limits the distance between the limit member 10 and the bearing 2 to be smaller than the thickness of the extrusion member 9. In other words, the distance between the limit member 10 and the blocking part 6 is smaller than the sum of the thicknesses of the extrusion member 9, the bearing 2, the pressure member 8 and the detection member 7. The extrusion member 9 with a smaller elastic modulus is deformed first, thereby bringing about floating ability. Having floating ability actually means that the extrusion member 9 always has the ability to elastically deform during normal operation, so that the whole is in an extruded state, ensuring that the pressure member 8 always applies pressure to the detection member 7, and the detection member 7 is always in a deformed state, so that the detection member 7 can be deformed when the lifting table encounters resistance in the up and down directions.

[0062] The pressure-applying member 8 abuts against the detection member 7 and applies pre-pressure to the detection member 7, and the detection member 7 is in a pre-deformed state; if the pressure-applying member 8 does not apply pre-pressure to the detection member 7, pressure will be applied to the detection member 7 only when the pressure-applying member 8 moves upward, then only obstacles from above can be detected. If the obstacle comes from below, the pressure applied by the pressure-applying member 8 to the detection member 7 is always zero, and it cannot play the role of detecting obstacles.

[0063] Compared with the existing products, the induction sheet 11 is no longer arranged on the motor box 3, but is mainly arranged on the base 1 and on the detection member 7 in the base 1. Specifically, the accommodating space 5 for installing the bearing 2 at the lower part of the base 1 is improved. In addition to the bearing 2, the accommodating space 5 is also provided with a detection member 7, a pressure member 8, an elastic ring and a retaining spring 10. The detection member 7 and the pressure member 8 are located above the bearing 2, and the elastic ring and the retaining spring 10 are located below the bearing 2; the elastic ring is against the bearing 2, and after the retaining spring 10 is snapped into the base 1 to complete the overall installation, the elastic ring is restricted in the up and down directions, and the elastic ring is compressed (caused by the gap between the position where the retaining spring 10 is snapped in and the bearing 2 is smaller than the thickness of the elastic ring), and always gives the bearing 2 an upward elastic force; The inner circumference of the pressure piece 8 bulges upward and presses on the detection piece 7. The upper part of the outer circumference of the detection piece 7 is blocked by the base 1. The elastic force of the elastic ring will be transmitted to the pressure piece 8. The pressure piece 8 always presses the detection piece 7, giving the detection piece 7 pressure to produce a deformation trend. The sensor piece 11 is set on the detection piece 7 and detects the deformation amount on the detection piece 7, that is, the change in force. Due to the presence of the elastic ring, the bearing 2 and the pressure piece 8 can float. When the lifting table encounters resistance, the bearing 2 and the pressure piece 8 will float, the force on the detection piece 7 will change significantly, and the deformation detected by the sensor piece 11 will also be more obvious, making the resistance detection more sensitive. Moreover, the ability of the bearing 2 and the pressure piece 8 to float up and down enables the sensor piece 11 to detect resistance in both the upper and lower directions of the table top.

[0064] The deformation amount in the pre-deformation state can be set to zero point. How to judge the deformation amount and whether resistance is encountered (acceptable deformation amount range) is determined by the program of the control unit.

[0065] The method of using this structure is: place the detection part 7, pressure part 8, bearing 2, extrusion part 9 and limit part 10 in the accommodating space 5 from top to bottom in sequence; install the structure in the lifting table, relatively fix the base 1 and the motor box 3, relatively fix the bearing 2 and the screw rod 4, and the structure connects the motor box 3 and the screw rod 4 of the lifting table.

[0066] As shown in Figures 8 and 9, when the table top fixedly connected to the motor box 3 in the lifting table moves upward and encounters resistance: the motor box 3 tends to move downward relative to the screw rod 4, the base 1 and the limit member 10 float downward relative to the bearing 2, and the extrusion member 9 is deformed accordingly. The detection member 7 is affected by the blocking part 6 and has a tendency to move downward relative to the pressure member 8. The relative force between the pressure member 8 and the detection member 7 increases, and the detection member 7 produces a deformation greater than the pre-deformation state. The sensor sheet 11 detects the deformation amount of the detection member 7 in this process and transmits the converted signal to the control unit. The control unit controls the motor of the lifting table to stop and rotate in the opposite direction, so that the table top stops and then descends.

[0067] As shown in Figures 8 and 10, when the table top moves downward and encounters resistance: the motor box 3 tends to move upward relative to the screw rod 4, the base 1 and the limit member 10 float upward relative to the bearing 2, and the extrusion member 9 is deformed accordingly. The blocking part 6 floats upward away from the pressure member 8, and the relative force between the pressure member 8 and the detection member 7 is reduced. The deformation of the detection member 7 will be smaller than the deformation in the pre-deformation state. The sensor sheet 11 detects the deformation amount of the detection member 7 in this process and transmits the converted signal to the control unit. The control unit controls the motor to stop and rotate in the opposite direction, so that the table top stops and then rises.

[0068] When encountering actual resistance, the bearing 2 and the pressure piece 8 are stationary, and the base 1, the limit piece 10 and the blocking part 6 on the base 1 will float relative to the bearing 2 and the pressure piece 8. The extrusion piece 9 can always give the bearing 2 and the pressure piece 8 elastic force. The elastic force changes with the floating of the limit piece 10, but the elastic force always makes the pressure piece 8 press against the detection piece 7 without separating, and can also restore the original position relationship of the various components in the structure after the lifting table leaves the obstacle; the bearing 2 and the pressure piece 8 are stationary, and the pressure piece 8 always abuts against the detection piece 7. When the blocking part 6 floats with the base 1, the force of the blocking part 6 on the detection piece 7 is changed, and the detection piece 7 is deformed under the joint action of the pressure piece 8 and the blocking part 6, so as to determine the resistance situation.

Claims

1. A bidirectional high-sensitivity detection structure for encountering obstacles, characterized in that: The invention comprises a base and a bearing, wherein the base is configured to be connected to a motor box, the bearing is configured to be connected to a screw rod, the base has an accommodating space, and a blocking portion is provided at the end of the accommodating space; a detecting member and a pressure member are provided in the accommodating space between the bearing and the blocking portion, and an extruding member and a limiting member are provided in the accommodating space on the other side of the bearing; the pressing member abuts against the bearing, the detecting member is located between the pressure member and the blocking portion, the extruding member abuts against the bearing, the limiting member abuts against the extruding member and is relatively fixedly connected to the base in an axial direction; the detecting member and the extruding member are elastic, and the limiting member is configured to limit the distance between the limiting member and the bearing to be less than the thickness of the extruding member, The extrusion piece is compressed to generate elastic force; the extrusion piece is configured to give the bearing an elastic force in the direction of the pressure piece, and enable the bearing and the pressure piece to have floating ability; the bearing presses the pressure piece and gives the pressure piece a force toward the detection piece, the pressure piece presses against the detection piece and applies pre-pressure to the detection piece, the detection piece is in a pre-deformed state, when the lifting table encounters resistance, the pressure piece and the bearing float, the pressure given to the detection piece by the pressure piece changes, and the detection piece produces a deformation different from the pre-deformed state; the detection piece is provided with a sensor sheet for detecting the deformation amount of the detection piece, and the sensor sheet is configured to convert the deformation amount of the detection piece into an electrical signal for judging the resistance situation.

2. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: Along the radial direction, the inner wall of the accommodating space extends inwardly to form the blocking portion, which is annular; the pressure piece is annular, and the inner edge of the pressure piece protrudes upward to form a pressing portion, which abuts against the inner edge of the detection piece.

3. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The accommodating space is through-connected from top to bottom, and the blocking part is arranged at the upper opening of the accommodating space; the detecting member, the pressure member, the bearing, the extruding member and the limiting member are arranged in the accommodating space in sequence from top to bottom.

4. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The detection piece is in the shape of a flat sheet.

5. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The detection piece is an elastic sheet.

6. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The limiting member is a clip spring, and the inner wall of the accommodating space is correspondingly provided with an annular groove for the clip spring to be inserted into.

7. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The pressure-applying member is a rigid member.

8. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The extrusion piece is a rubber ring.

9. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The induction sheet is a strain sheet or a piezoelectric sheet; the induction sheet is in the shape of a circular sheet, a rectangular sheet or a fan-shaped sheet; the induction sheet is pasted on the detection piece and is located beside the screw rod.

10. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The base is provided with an avoidance hole, which is connected to the accommodating space. The avoidance hole is configured to avoid the signal line of the sensor sheet so that the signal line passes through the base and is connected to the control unit of the lifting table.

11. The structure for bidirectional high-sensitivity detection of obstruction according to claim 1, characterized in that: The base includes a fixing plate and a mounting portion. The fixing plate is configured to be fixedly connected to the motor box. The mounting portion is located below the fixing plate and protrudes downward from the bottom of the motor box. The accommodating space is opened on the mounting portion. When the induction sheet is set on the detection piece, the induction sheet is located below the bottom of the motor box.

12. The structure for bidirectional high-sensitivity detection of obstruction according to claim 11, characterized in that: The sensor is located 0.5-1cm below the motor box.

13. A method for using the bidirectional high-sensitivity detection structure for encountering obstacles according to any one of claims 1 to 12, characterized in that: The detection member, pressure member, bearing, extrusion member and limit member are placed in the accommodating space from top to bottom in sequence; the structure is installed in the lifting table, the base is relatively fixedly connected to the motor box, the bearing is relatively fixedly connected to the screw, and the structure connects the motor box of the lifting table to the screw; when the table board fixedly connected to the motor box in the lifting table moves upward and encounters resistance, the motor box has a tendency to move downward relative to the screw, the base and the limit member float downward relative to the bearing, and the extrusion member is deformed accordingly, and the detection member has a tendency to move downward relative to the pressure member under the action of the blocking part, the relative force between the pressure member and the detection member increases, and the detection member produces a deformation greater than the pre-deformation state, the sensor detects the deformation amount of the detection member in this process and transmits the converted signal to the control unit of the lifting table, the control unit controls the motor of the lifting table to stop and reverse rotation, so that the table board stops and then descends; When the table top moves downward and encounters resistance, the motor box tends to move upward relative to the screw rod, and the base and the limit piece float upward relative to the bearing. The extrusion piece deforms accordingly, and the blocking part floats upward away from the pressure piece. The relative force between the pressure piece and the detection piece decreases, and the deformation of the detection piece will be smaller than the deformation in the pre-deformation state. The sensor sheet detects the deformation amount of the detection piece in this process and transmits the converted signal to the control unit. The control unit controls the motor to stop and rotate in the opposite direction, so that the table top stops and then rises.

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