Anti-pinch detection method of electric bed
By combining the linear displacement sensor and the pushing device, the problem of unstable detection of existing electric beds is solved, and anti-clip detection with low cost, simple installation and wide application range is achieved, ensuring accurate and safe detection.
Patent Information
- Application Number
- CN202510806448.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-16
- Publication Date
- 2025-08-15
AI Technical Summary
The anti-clip detection method of existing electric beds is expensive, complex installation process, and is susceptible to temperature, resulting in unstable detection and inability to adapt to electric beds of different sizes.
The anti-clip detection method combined with the linear displacement sensor and the pushing device is adopted. By obtaining the stroke and displacement values of the pushing device and the linear displacement sensor, it is determined whether the current displacement change is less than the stroke change, and the pushing device stops or continues to work to ensure that the detection is accurate and not affected by environmental factors.
It realizes anti-clip detection with low cost, simple installation and wide application range. The detection results are accurate and are not affected by temperature and humidity, and avoids damage caused by foreign objects being clamped.
Smart Images
Figure CN120477524A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of smart home technology, and in particular to an anti-pinch detection method for an electric bed. Background Art
[0002] With the continuous development of smart homes, beds are becoming increasingly electrified and intelligent, and electric beds are gaining popularity among consumers. Some of the bed panels on electric beds can be moved relative to the bed frame, for example, by lifting and rotating, allowing the user to find a relatively comfortable position. During the lowering process, due to the large gap between the movable bed panel and the bed frame, there is a risk of the user being accidentally pinched or foreign objects being trapped in the gap, preventing a proper return to the bed. Existing anti-pinch detection methods for electric beds generally involve placing a circle of sensors along the edge or bed rail or placing numerous airbags on the bed panel. However, this method is costly and requires a complex installation process, and it also requires customization for electric beds of different sizes. Furthermore, most sensors currently used in electric bed anti-pinch methods are affected by temperature, making detection instability prone to errors. Summary of the Invention
[0003] The purpose of the present invention is to provide an anti-pinch detection method for an electric bed in response to the defects and shortcomings of the existing technology, which has the advantages of simple installation, low cost, accurate detection and a wide range of applications.
[0004] To achieve the above object, the present invention adopts a technical solution: an anti-pinch detection method for an electric bed, the anti-pinch detection method comprising the following steps: Obtaining an original stroke value and a first current stroke value corresponding to the output end of the pushing device, and an original displacement value and a current displacement value corresponding to the linear displacement sensor; Obtaining a first current stroke change based on the original stroke value and the first current stroke value, and obtaining a current displacement change based on the original displacement value and the current displacement value; Determining whether the current displacement change is less than the first current stroke change; If the current displacement change is less than the first current stroke change, it is determined that a foreign object is clamped between the bed frame and the second bed board, and the pushing device is controlled to stop working.
[0005] The present invention is further configured to further include the following steps after the step of controlling the pushing component to stop working: Controlling the pushing device to push the second bed board to lift; Obtaining a second current stroke value corresponding to the output end of the pushing device; Obtaining an actual lift stroke change based on the first current stroke value and the second current stroke value; Determining whether the actual lift stroke change is equal to a preset lift stroke change; If the actual lifting stroke change is equal to the preset lifting stroke change, it is determined that the second bed board is lifted to a preset position so that the user can remove the foreign object.
[0006] The present invention further provides that the anti-pinch detection method further includes the following steps: If the current displacement change is equal to the first current stroke change, it is determined that no foreign matter is clamped between the bed frame and the second bed board; and the pushing device is controlled to continue working.
[0007] The present invention further provides that the electric bed includes: a bed frame, a first bed board mounted on the bed frame, a second bed board with one end hinged to one side of the first bed board or on the bed frame, a pushing component with one end hinged to the bed frame and a movable end hinged to the second bed board, for pushing the second bed board to lift, and a linear displacement sensor arranged parallel to the pushing component, with a telescopic end mounted on the second bed board and located on the same horizontal line as the hinge between the movable end and the second bed board.
[0008] The present invention further provides that the pushing assembly includes: a pushing device hinged on the bed frame and a push rod with one end abutting against the output end of the pushing device and the other end hinged on the second bed board.
[0009] The present invention further provides that the linear displacement sensor includes: a sensor body arranged parallel to the pushing assembly, and a measuring piece having one end connected to the sensor body and the other end assembled on the second bed board and located on the same horizontal line as the hinge between the movable end and the second bed board.
[0010] By adopting the above technical solution, the present invention has the following beneficial effects: In the present invention, by determining whether the current displacement change is less than the first current stroke change, it is determined whether a foreign object is trapped between the bed frame and the second bed board. This anti-pinch detection method is accurate and unaffected by ambient environmental factors such as temperature and humidity. Furthermore, the displacement value is acquired by a linear displacement sensor, and the stroke value is acquired by a pushing device. This method is low-cost, has a wide range of applications, and is not limited by the size of the bed frame. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0012] Figure 1 It is a schematic flow chart of the anti-pinch detection method in the present invention; Figure 2 is another flow chart of the anti-pinch detection method of the present invention; Figure 3 This is a schematic structural diagram of the electric bed in the present invention when the second bed board is raised; Figure 4 This is another structural schematic diagram of the electric bed in the present invention when the second bed board is raised; Figure 5 This is a schematic structural diagram of the electric bed in the present invention when the second bed board is in a completely flat state; Figure 6 This is another structural schematic diagram of the electric bed in the present invention when the second bed board is in a completely flat state.
[0013] Explanation of the accompanying reference numerals: 110, bed frame; 120, first bed board; 130, second bed board; 140, pushing assembly; 141, pushing device; 142, push rod; 150, linear displacement sensor; 151, sensor body; 152, measuring piece. DETAILED DESCRIPTION
[0014] The present invention will be further described in detail below with reference to the accompanying drawings.
[0015] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.
[0016] In the description of this application, it should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Technologies, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further discussed in subsequent figures.
[0017] It should be noted that the terms "first," "second," etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than those illustrated or described herein, and that the objects distinguished by "first," "second," etc. are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.
[0018] This embodiment relates to an anti-pinch detection method for an electric bed, referring to Figure 3-Figure 6 The electric bed includes: a bed frame 110, a first bed board 120, a second bed board 130, a pushing assembly 140, and a linear displacement sensor 150. The first bed board 120 is mounted on the bed frame 110; one end of the second bed board 130 is hinged to a side of the first bed board 120 or to the bed frame 110; one end of the pushing assembly 140 is hinged to the bed frame 110, and its movable end is hinged to the second bed board 130; the pushing assembly 140 is used to push the second bed board 130 to lift. The linear displacement sensor 150 is arranged parallel to the pushing assembly 140; the telescopic end of the linear displacement sensor 150 is mounted on the second bed board 130 and is located on the same horizontal line as the hinge point of the movable end with the second bed board 130. In this embodiment, one end of the second bed board 130 is hinged to a side of the first bed board 120. In some embodiments, one end of the second bed board 130 can also be hinged to the bed frame 110.
[0019] In this embodiment, the starting position for the descent of the second deck 130 is the highest point at which the free end of the second deck 130 can be raised. Accordingly, the point where the output end of the push device 141 abuts the push rod 142 at this point is the starting position for the descent of the push assembly 140. In some embodiments, the starting position for the descent of the second deck 130 and the push assembly 140 can be set by the user. In this embodiment, the direction in which the second deck 130 is leveled downward is defined as the positive direction.
[0020] In this embodiment, referring to Figure 3-Figure 6The pushing assembly 140 includes a pushing device 141 hinged to the bed frame 110, and a push rod 142, one end of which abuts the output end of the pushing device 141 and the other end of which is hinged to the second bed board 130. Specifically, when the second bed board 130 is raised, the output end of the pushing device 141 pushes the push rod 142 outward, thereby raising the second bed board 130. When the second bed board 130 is lowered, the output end of the pushing device 141 retracts downward, causing the push rod 142 to lose its support and descend. Consequently, the second bed board 130, without the support of the push rod 142, descends under the action of its own gravity. Compared to conventional connection arrangements, the abutment arrangement at the contact point between the pusher 141 and the push rod 142 in the push assembly 140 effectively prevents foreign objects from being trapped between the bed frame 110 and the second bed board 130. This is due to the combined force of the pusher 140 pulling the second bed board 130 downward, the weight of the second bed board 130 itself, and the weight of the mattress, among other factors, which could exacerbate damage to the foreign object. The foreign object may be a body part of the user or other object. Furthermore, the linear displacement sensor 150 includes a sensor body 151 and a measuring member 152. The sensor body 151 is arranged parallel to the push assembly 140 to ensure accurate measurement. The measuring member 152 is connected to the sensor body 151 at one end and mounted on the second bed board 130 at the other end. The measuring member 152 is aligned with the hinged joint between the movable end of the push assembly 140 and the second bed board 130. During assembly, the measuring member 152 is parallel to the pusher 141 and the push rod 142 and is fully straightened. Specifically, the sensor body 151 is assembled on the pushing assembly 140 through a connecting plate, and the assembly location is close to one end where the pushing assembly 140 is hinged to the bed frame 110 .
[0021] The linear displacement sensor 150 can directly display linear displacement values in real time, thereby directly reflecting the displacement values of the second bed plate 130 during lifting and lowering. The propulsion assembly 140 also includes a control device electrically connected to the propulsion device 141. The stroke value corresponding to the propulsion device 141 is acquired by the control device. In this embodiment, the propulsion device 141 primarily comprises a brushed DC motor, a feedback board with a built-in Hall position sensor, and a transmission mechanism (such as a gearbox and a lead screw nut). The control device, electrically connected to the propulsion device, drives the brushed motor forward or reverse using PWM (pulse width modulation) signals. The motor's rotational motion is ultimately converted into axial linear upward or downward motion of the push rod through the transmission mechanism (typically including a reduction gear). As the motor rotor rotates, the Hall feedback board synchronously generates a position feedback signal (for example, four square wave pulse signals for each rotor rotation). By counting these Hall pulse signals, the control device can accurately determine the actual number of motor rotations and angle. The number of motor rotations is determined by the transmission mechanism's reduction ratio and mechanical transmission relationship (such as the lead of the lead screw). Therefore, the control device can calculate the axial stroke value of the output end of the pushing device 141 in real time based on the accumulated number of Hall pulses. Specifically, the original stroke value refers to the stroke value obtained at the starting position of the output end of the pushing device 141 when the second bed plate 130 is at the starting position of descent. The first current stroke value refers to the number of pulses of the feedback signal obtained in real time during the process in which the output end of the pushing device 141 pushes the push rod 142 axially upward and thereby pushes the second bed plate 130 to rise or the output end of the pushing device 141 descends axially, and then the actual stroke value of the output end of the pushing device 141 is calculated. In this embodiment, the stroke value per pulse is 0.1mm (calculated based on the example of "screw lead L is 8mm / turn, reduction ratio R is 20:1, PPR is 4"). In some embodiments, the stroke value per pulse can also be 0.2mm. The numerical value of the stroke value per pulse is obtained according to the actual lead and reduction ratio.
[0022] In addition, in this embodiment, the stroke limit of the output end of the pushing device 141 is set to 190 mm. In some embodiments, the stroke limit of the output end of the pushing device 141 can also be set to 140 mm. The stroke limit of the output end of the pushing device 141 is determined by the performance of the pushing device itself or by the different bed boards that push different parts of the human body.
[0023] In this embodiment, the linear displacement sensor 150 is configured as a pull-wire displacement sensor. In some embodiments, the linear displacement sensor 150 may also be a fiber optic linear displacement sensor or a photoelectric linear displacement sensor. In some embodiments, the driving device 141 may also be another driving device that can precisely control the output end travel.
[0024] In this embodiment, the electric bed further includes a control assembly electrically connected to the propulsion assembly 140 and the linear displacement sensor 150. The control assembly includes a data acquisition unit, a calculation unit, a judgment unit, and a control unit. The data acquisition unit is used to acquire the original stroke value and current stroke value corresponding to the propulsion assembly 140. The acquisition unit is also used to acquire the original displacement value and current displacement value of the linear displacement sensor 150. The data acquisition unit transmits the acquired stroke value corresponding to the propulsion assembly 140 and the displacement value corresponding to the linear displacement sensor 150 to the calculation unit. The calculation unit subtracts the original stroke value from the current stroke value to obtain the difference between the two, and the absolute value of the difference is the current stroke change. The calculation unit also subtracts the original displacement value from the current displacement value to obtain the difference between the two, and the absolute value of the difference is the current displacement change. The judgment unit receives the current displacement change and the current stroke change output by the calculation unit, compares them, and ultimately outputs a judgment result to the control unit for controlling the propulsion assembly.
[0025] Reference Figure 1 , the anti-pinch detection method includes the following steps: In step S210, the original stroke value and the first current stroke value corresponding to the output end of the pushing device 141, as well as the original displacement value and the current displacement value corresponding to the linear displacement sensor 150 are obtained; In step S220, a first current stroke change is obtained based on the original stroke value and the first current stroke value, and a current displacement change is obtained based on the original displacement value and the current displacement value; In step S230, it is determined whether the current displacement change is less than the first current stroke change; If the current displacement variation is less than the first current stroke variation, in step S240 , it is determined that a foreign object is clamped between the bed frame 110 and the second bed board 130 , and the pushing device 141 is controlled to stop working.
[0026] The anti-pinch detection method of the electric bed is achieved by assembling a linear displacement sensor 150 on the electric bed. The linear displacement sensor 150 is arranged parallel to the push assembly 140, and the telescopic end is assembled on the second bed board 130 and is located at the same horizontal line as the hinge of the movable end of the push assembly 140 and the second bed board 130. It can intuitively reflect the displacement value of the lifting or lowering of the second bed board 130; the stroke value is accurately obtained by a control device electrically connected to the push device 141; and the linear displacement sensor 150 is not affected by temperature and humidity, and the measurement is more accurate, thereby making the detection result of whether a foreign object is clamped between the bed frame 110 and the second bed board 130 more accurate. The linear displacement sensor 150 and the push assembly 140 in the anti-pinch detection method of the electric bed are simple to install and low in cost, have a wide range of applications, and are not limited by the size of the bed frame 110.
[0027] Specifically, in the process of resetting the second bed board 130, that is, lowering it to the bed frame 110, the current displacement change of the linear displacement sensor 150 is less than the first current stroke change, indicating that the current lowering displacement change of the second bed board 130 is less than the current stroke change corresponding to the pushing device 141, that is, during the normal descent of the pushing device 141 and the push rod 142, the second bed board 130 did not descend with the descent of the push rod 142, indicating that a foreign object is clamped between the bed frame 110 and the second bed board 130, blocking the normal descent of the second bed board 130. At this time, the pushing device 141 is controlled to stop working to avoid secondary injury.
[0028] Further, refer to Figure 2 After the step of controlling the pushing device 141 to stop working, the method further includes the following steps: In step S250, the pushing device 141 is controlled to push the second bed board 130 to lift up; In step S260, a second current stroke value corresponding to the output end of the pushing device 141 is obtained; In step S270, based on the first current stroke value and the second current stroke value, an actual lifting stroke change is obtained; In step S280, it is determined whether the actual lifting stroke change is equal to the preset lifting stroke change; If the actual lifting stroke variation is equal to the preset lifting stroke variation, in step S290 , it is determined that the second bed board 130 is lifted to the preset position so that the user can remove the foreign object.
[0029] After determining that a foreign object is clamped between the bed frame 110 and the second bed board 130, the pushing device 141 is first controlled to stop working to avoid causing more serious damage to the foreign object, and then the pushing device 141 is controlled to push the second bed board 130 to lift. By judging whether the actual lifting stroke change is equal to the preset lifting stroke change, the user can remove the foreign object while avoiding excessive lifting of the second bed board 130, saving time.
[0030] In this embodiment, the actual lifting stroke change is also calculated by the calculation unit of the control component. The calculation unit makes a difference based on the first current stroke value and the second current stroke value to obtain the difference between the two. The absolute value of the difference is the actual lifting stroke change. The preset lifting stroke change is stored in the judgment unit. The judgment unit is also used to receive the actual lifting stroke change and the preset lifting stroke change output by the calculation unit, and compare them. The final output judgment result is transmitted to the control unit to control the pushing component 140. The preset lifting stroke change is the stroke change of the output end of the pushing device 141 along the axial upward direction corresponding to 100 pulses counted by the control device in the pushing component 140. According to the above statement that "in this embodiment, 1 pulse number corresponds to the axial movement stroke value of the output end of the pushing device 141 of 0.1mm", it can be seen that in this embodiment, the preset lifting stroke change value is 10mm. In this process, the value of the actual displacement change corresponding to the linear displacement sensor is the same as the value of the preset lifting stroke change. The preset position of the second bed board 130 refers to the position of the second bed board 130 after the pushing assembly 140 lifts the second bed board 130 axially upward by a preset lifting stroke variation. In some embodiments, the preset lifting stroke variation is 20 mm.
[0031] In some embodiments, reference Figure 2 This anti-pinch detection method further includes the following steps: if the current displacement change is equal to the first current stroke change, then in step S310, it is determined that no foreign object is trapped between the bed frame 110 and the second bed board 130; and the propulsion device 141 is controlled to continue operating. Specifically, the raising and lowering of the second bed board 130 is actually dependent on the movement of the output end of the propulsion device 141 in the propulsion assembly 140. Therefore, under normal circumstances (i.e., when no foreign object is trapped between the bed frame 110 and the second bed board 130), the stroke change of the output end of the propulsion device 141 is equal to the displacement change of the second bed board 130.
[0032] The above is only used to illustrate the technical solution of the present invention and is not intended to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.
Claims
1. A method for detecting anti-pinch of an electric bed, characterized in that: The anti-pinch detection method comprises the following steps: Obtaining an original stroke value and a first current stroke value corresponding to an output end of the pushing device (141), and an original displacement value and a current displacement value corresponding to the linear displacement sensor (150); Obtaining a first current stroke change based on the original stroke value and the first current stroke value, and obtaining a current displacement change based on the original displacement value and the current displacement value; Determining whether the current displacement change is less than the first current stroke change; If the current displacement change is less than the first current stroke change, it is determined that a foreign object is clamped between the bed frame (110) and the second bed board (130), and the pushing device (141) is controlled to stop working.
2. The anti-pinch detection method for an electric bed according to claim 1, characterized in that: After the step of controlling the pushing device (141) to stop working, the following steps are also included: controlling the pushing device (141) to push the second bed board (130) to lift; Obtaining a second current stroke value corresponding to the output end of the pushing device (141); Obtaining an actual lift stroke change based on the first current stroke value and the second current stroke value; Determining whether the actual lift stroke change is equal to a preset lift stroke change; If the actual lifting stroke change is equal to the preset lifting stroke change, it is determined that the second bed board (130) is lifted to a preset position so that the user can remove the foreign object.
3. The anti-pinch detection method for an electric bed according to claim 1, characterized in that: The anti-pinch detection method further comprises the following steps: If the current displacement change is equal to the first current stroke change, it is determined that no foreign matter is clamped between the bed frame (110) and the second bed board (130); and the pushing device (141) is controlled to continue working.
4. The anti-pinch detection method for an electric bed according to any one of claims 1 to 3, characterized in that: The electric bed comprises: a bed frame (110), a first bed board (120) mounted on the bed frame (110), one end of which is hinged to one side of the first bed board (120) or a second bed board (130) of the bed frame (110), a pushing assembly (140) having one end hinged to the bed frame (110) and a movable end hinged to the second bed board (130) for pushing the second bed board (130) to lift, and a linear displacement sensor (150) arranged parallel to the pushing assembly (140), a telescopic end of which is mounted on the second bed board (130) and is located on the same horizontal line as the hinge point between the movable end and the second bed board (130).
5. The anti-pinch detection method for an electric bed according to claim 4, characterized in that: The pushing assembly (140) comprises: a pushing device (141) hinged on the bed frame (110) and a push rod (142) with one end abutting against the output end of the pushing device (141) and the other end hinged on the second bed board (130).
6. The anti-pinch detection method for an electric bed according to claim 4, characterized in that: The linear displacement sensor (150) comprises: a sensor body (151) arranged parallel to the pushing assembly (140), and a measuring piece (152) having one end connected to the sensor body (151) and the other end mounted on the second bed board (130) and located on the same horizontal line as the hinged connection between the movable end and the second bed board (130).