A handheld workpiece measuring device

Abstract

This invention discloses a handheld workpiece measuring device, including a handheld unit and a measuring processing unit. The handheld unit includes a central rod, a scissor-type connecting frame, a locking fastener, a fixing buckle, measuring feet, and a tension component. Handles are symmetrically fitted at the upper and lower ends of the central rod, and both handles can slide up and down along the central guide rod. Movable frames are symmetrically arranged on the left and right sides of the central rod, parallel to each other. Two connecting seats are vertically spaced on the movable frames, and both connecting seats can slide vertically along the movable frames. This invention has a unique structure and ingenious design, effectively solving not only the problem of limited measurement function of existing calipers but also the problem of inconvenience in storage and carrying due to the inherent structural limitations of existing calipers.

Description

Technical Field

[0001] This invention belongs to the field of measuring instrument technology, specifically relating to a handheld workpiece measuring device. Background Technology

[0002] A hydraulic cylinder is a hydraulic actuator that converts hydraulic energy into mechanical energy and performs linear reciprocating motion (or oscillating motion). A hydraulic cylinder basically consists of a cylinder barrel and cylinder head, a piston and piston rod, a sealing device, a cushioning device, and a venting device. After manufacturing, the dimensions of each component of a hydraulic cylinder need to be measured to verify that each component meets the manufacturing requirements.

[0003] Currently, when inspecting the dimensions of various components of a hydraulic cylinder, quality inspectors use calipers to measure these dimensions. However, existing calipers have limited measuring functions; calipers used for measuring distances cannot measure external diameters, and calipers used for measuring external diameters cannot measure internal holes. This necessitates purchasing many different types of calipers to handle various situations, leading to frequent caliper changes for quality inspectors to meet work requirements. Furthermore, the different usage methods for each type of caliper can impact the efficiency of quality inspection. Moreover, the measuring range of existing calipers is related to their own size; small calipers can only measure small workpieces, and large calipers can only measure large workpieces. Traditional calipers are bulky and inconvenient to store and carry. Summary of the Invention

[0004] In response to the defects and problems existing in existing calipers, this invention provides a handheld workpiece measuring device. This device has a unique structure and ingenious design, which can not only effectively solve the problem of the single measurement function of existing calipers, but also effectively solve the problem that existing calipers are inconvenient to store and carry due to their own structure.

[0005] The solution adopted by this invention to solve its technical problem is: a handheld workpiece measuring device, comprising a handheld unit and a measuring processing unit. The handheld unit includes a central rod, a scissor-type connecting frame, a locking fastener, a fixing buckle, measuring feet, and a tension assembly. Handles are symmetrically fitted at the upper and lower ends of the central rod, and both handles can slide up and down along the central guide rod. Movable frames are symmetrically arranged on the left and right sides of the central rod, parallel to the central rod. Two connecting seats are vertically spaced on the movable frames, and both connecting seats can slide vertically along the movable frames. Measuring feet are hinged to the end of each movable frame away from the central rod via a fixing buckle, and the position of the measuring feet on the movable frame can be adjusted via the fixing buckle. The locking fastener is fitted onto the fixing buckle, and the locking fastener can lock the measuring feet to keep them parallel to the movable frame. The system can be configured in either a horizontal or vertical position. Each movable frame is connected to the central rod by a scissor-type connecting frame. The scissor-type connecting frame includes multiple scissor rod groups arranged laterally. Adjacent scissor rod groups are hinged together. The two ends of the scissor rod groups adjacent to the movable frame are hinged to their corresponding connecting seats. The two ends of the scissor rod groups adjacent to the central rod are hinged to the upper and lower handles. The scissor-type connecting frames on both sides of the central rod are connected by tension members, which, in their natural state, will drive the two scissor-type connecting frames to retract towards the central rod. The measurement and processing unit is installed on the handle. After the measurement and processing unit selects the corresponding calculation mode based on the state between the measuring foot and the movable frame, the measurement and processing unit can automatically calculate the measurement results based on the distance between the two handles and the number of scissor rod groups.

[0006] The center rod has a vertical groove extending backward through the rod body in the middle, and two sliding rods are arranged vertically at intervals in the groove, and the sliding rods can slide vertically along the groove; the handle has a vertical insertion hole in the middle that matches the center rod, and is fitted onto the center rod and connected to the adjacent sliding rod.

[0007] The movable frame has multiple insertion holes evenly spaced vertically at one end away from the central rod. The inner end of the fixing buckle has a slot that matches the thickness of the movable frame, and the front and rear side walls of the slot are matched with external insertion holes that match the insertion holes. When the slot end of the fixing buckle is inserted into the movable frame so that the external insertion hole overlaps with the insertion hole, the fixing buckle is fixed together with the movable frame by a pin.

[0008] The fixed buckle has a vertically extending hinge groove at the end away from the movable frame. The root of the measuring foot is matched and installed in the hinge groove by a pin, and the measuring foot can rotate around the hinge groove. The measuring foot can be locked in the hinge groove by a locking fastener.

[0009] The locking device includes a fixing pin arranged longitudinally. The end of the fixing buckle away from the movable frame has two positioning holes with the pin at the root of the probe as the center and spaced circumferentially along the hinge groove. The root of the probe is matched with an inner insertion hole corresponding to the two positioning grooves. When the inner insertion hole overlaps with the positioning hole, inserting the pin can lock the probe to the movable buckle. When the inner insertion hole at the root of the probe coincides with the first positioning hole, the probe and the movable frame are in a parallel state. When the inner insertion hole at the root of the probe coincides with the second positioning hole, the probe and the movable frame are in a perpendicular state.

[0010] The tension component includes return springs symmetrically arranged on the front and rear sides of the central rod. The left and right ends of the return springs are respectively connected to the middle pins of the adjacent scissor rod groups of the left and right scissor connecting frames. In the natural state, the return springs will drive the two scissor connecting frames to retract towards the central rod side.

[0011] The measurement processing unit includes a main controller, a display module, a voice broadcast module, a laser ranging module, a mode selection module, and a quantity input module. The mode selection module is connected to the main controller and can control the calculation processor to switch the corresponding calculation mode according to the state between the measuring foot and the movable frame. The quantity input module is connected to the main controller and is used to send the accurate number of scissor arms in the device to the main controller. The calculation button is matched and installed on the handle and connected to the main controller, and is used to send the start calculation command to the main controller. The laser ranging module is matched and installed on the handle and connected to the main controller, and is used to measure the distance between the two handles after the main controller receives the start calculation command, and send the distance data to the main controller.

[0012] The calculation modes include an inner diameter calculation mode and a non-inner diameter calculation mode. When the measuring foot is perpendicular to the movable frame, the calculation processor is controlled by the mode selection module to select the inner diameter calculation mode. When the measuring foot is parallel to the movable frame, the calculation processor is controlled by the mode selection module to select the non-inner diameter calculation mode.

[0013] The beneficial effects of this invention are as follows: The handheld workpiece measuring device provided by this invention can adjust the measuring function of the handheld workpiece measuring device by adjusting the state between the measuring feet and the movable frame and changing the calculation mode of the measurement processing unit. This allows it to measure not only the inner diameter of the workpiece but also the outer diameter of the workpiece and the distance between two planes, thus effectively solving the problem of the single measurement function of existing calipers. After measurement, the measuring personnel can directly obtain the measurement results through the measurement processing unit, making it convenient to use. During use, the number of scissor arms can be added according to the intuitive size of the workpiece, flexibly adjusting the measurement range of the device so that it can be used for measuring workpieces of different sizes. In the natural state, the tension element will drive the two scissor arms to retract towards the central rod, so that the device itself is in a tightened state, making it convenient to carry and store. This not only effectively solves the problem of the single measurement function of existing calipers but also effectively solves the problem that existing calipers are inconvenient to store and carry due to their own structure. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention in its contracted state.

[0015] Figure 2 This is one of the schematic diagrams of the three-dimensional structure of the present invention in its extended state.

[0016] Figure 3 This is the second schematic diagram of the three-dimensional structure of the present invention in its extended state.

[0017] Figure 4 This is a schematic diagram of the three-dimensional structure of the central rod of the present invention.

[0018] Figure 5 This is a schematic diagram of the movable frame structure of the present invention.

[0019] Figure 6 This is a schematic diagram showing the relationship between the measuring foot and the fixing buckle of the present invention.

[0020] The following numbers are used in the diagram: 1 is the center rod, 11 is the slide groove, 12 is the slide rod, 2 is the scissor connector, 21 is the scissor rod assembly, 211 is the support rod, 3 is the handle, 31 is the insertion hole, 4 is the movable frame, 41 is the connecting seat, 42 is the insertion hole, 5 is the measuring foot, 51 is the inner insertion hole, 6 is the fixing buckle, 61 is the outer insertion hole, 62 is the pin, 63 is the slot, 64 is the hinge slot, 65 is the positioning insertion hole, 7 is the pin, 8 is the fixing pin, and 9 is the return spring. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Example 1

[0023] To address the problems mentioned in the background section, this invention provides a handheld workpiece measuring device with a unique structure and ingenious design, such as... Figure 1-6 As shown, it includes a handheld unit and a measurement processing unit. The handheld unit includes a central rod 1, a scissor-type connecting frame 2, a locking fastener, a fixing buckle 6, a measuring foot 5, and a tension assembly. Handles 3 are symmetrically fitted at the upper and lower ends of the central rod 1, and both handles 3 can slide up and down along the central guide rod. Specifically:

[0024] like Figure 4 As shown, the center rod 1 has a vertical groove 11 extending backward through the rod body in the middle. Two sliding rods 12 are arranged vertically at intervals in the groove 11, and the sliding rods 12 can slide vertically along the groove. The handle 3 has a vertical insertion hole 31 that matches the center rod in the middle, and is fitted onto the center rod 1 and connected to the adjacent sliding rod 12. Thus, during use, the constraint of the sliding rod 12 and the groove 11 can prevent the handle from falling off the center rod when sliding along the center rod.

[0025] The center rod 1 is symmetrically provided with movable frames 4 on the left and right sides. The movable frames 4 are arranged parallel to the center rod. Two connecting seats 41 are provided vertically on the movable frames 4, and both connecting seats 41 can slide vertically along the movable frames. Specifically, the middle part of the movable frame 41 is provided with a sliding groove that extends backward through the frame body. The connecting seats 41 are matched and installed in the sliding groove of the movable frame and can slide up and down along the sliding groove of the movable frame 4.

[0026] Both movable frames 4 have a measuring foot 5 hinged to the end furthest from the center rod via a fixing buckle 6. The position of the measuring foot 5 on the movable frame can be adjusted via the fixing buckle. The locking fastener is matched and installed on the fixing buckle. The locking fastener can be used to switch the measuring foot to be parallel or perpendicular to the movable frame. Specifically:

[0027] like Figure 5 and Figure 6 As shown, the movable frame 4 has multiple evenly spaced vertical insertion holes 42 at one end away from the central rod. The inner end of the fixing buckle 6 has a slot 63 that matches the thickness of the movable frame. The front and rear side walls of the slot 63 are equipped with external insertion holes 61 that match the insertion holes 42. When the slot end of the fixing buckle is inserted into the movable frame so that the external insertion hole overlaps with the insertion hole, the fixing buckle is fixed to the movable frame by the pin 62. Since the external insertion hole is matched with the insertion hole, when the external insertion hole overlaps with the insertion hole, the end of the movable frame away from the central rod will contact the bottom of the slot, thus restraining the fixing buckle from shaking.

[0028] The fixed buckle 6 has a vertically extending hinge groove 64 at the end away from the movable frame. The root of the measuring foot 5 is fitted into the hinge groove 64 via a pin 7, and the measuring foot 5 can rotate around the hinge groove 64. The measuring foot can be locked in the hinge groove by a locking fastener. The locking fastener includes a fixing pin 8 arranged longitudinally. The front of the fixed buckle 6 at the end away from the movable frame has two positioning holes 65 spaced circumferentially around the pin at the root of the measuring foot. The root of the measuring foot is fitted with an inner insertion hole 51 corresponding to the two positioning grooves. When the measuring foot rotates around the pin, the inner insertion hole at the root of the measuring foot will coincide with the two positioning holes in sequence. When the inner insertion hole and the positioning hole overlap, inserting the fixing pin 8 can lock the measuring foot and the movable buckle. When the inner insertion hole at the root of the measuring foot coincides with the first positioning hole, the measuring foot and the movable frame are in a parallel state. When the inner insertion hole at the root of the measuring foot coincides with the second positioning hole, the measuring foot and the movable frame are in a perpendicular state.

[0029] Each movable frame is connected to the central rod by a scissor-type connecting frame 2. The scissor-type connecting frame 2 includes multiple scissor-type rod groups 21 arranged laterally. Adjacent scissor-type rod groups 21 are hinged together. The two ends of the scissor-type rod group on the side adjacent to the movable frame are respectively hinged to the corresponding connecting seats. The two ends of the scissor-type rod group on the side adjacent to the central rod are respectively hinged to the upper and lower handles. Specifically:

[0030] like Figure 1-3 As shown, the scissor rod assembly 21 includes two support rods 211 hinged together in the middle. The ends of the two support rods 211 of two adjacent connecting rod assemblies 211 are detachably hinged together. The ends of the two support rods 211 of the scissor rod assembly on the side adjacent to the movable frame in the scissor connecting frame 2 are respectively hinged to the corresponding connecting seats. The ends of the two support rods of the scissor rod assembly on the side adjacent to the central rod in the scissor connecting frame are respectively hinged to the corresponding handles. Thus, during use, when the two pressing blocks are held with one hand and moved towards each other along the central rod, the two scissor connecting frames will be squeezed and extend outward synchronously, thereby driving the movable frames on both sides to move the measuring feet outward and away from each other. Conversely, when the two handles move in opposite directions along the central rod, the two scissor connecting frames will retract synchronously towards the central rod, thereby driving the movable frames on both sides to move the measuring feet towards the central rod.

[0031] Furthermore, there are several ways in which the ends of the two support rods of adjacent linkage groups can be detachably hinged together. For example, the ends of the corresponding two support rods can be rotatably mounted on the same hinge pin, and the hinge pin can be detached axially as needed. Thus, by adding the number of linkage groups during use, the measurement range of multiple devices can be adjusted to adapt to parts of different sizes. There are several ways in which scissor linkage groups are connected to the two handles. For example, the ends of the two support rods of the scissor linkage group can be rotatably mounted on the slide rods connected to the two handles.

[0032] The scissor-type connecting frames on both sides of the center rod 1 are connected by tension members. In a natural state, the tension members will drive the two scissor-type connecting frames to retract towards the center rod. There are various types of tension members, such as: tension members include return springs 9 symmetrically arranged on the front and rear sides of the center rod. The left and right ends of the return springs 9 are respectively connected to the middle pins 7 of the adjacent scissor rod groups on the left and right sides. Thus, in a natural state, the return springs will drive the two scissor-type connecting frames to retract towards the center rod, keeping the handheld unit in a retracted state for easy carrying.

[0033] The measurement processing unit is mounted on the handle, and its control buttons are also located on the handle. After selecting the corresponding calculation mode based on the state between the measuring foot and the movable frame, the measurement processing unit can calculate the measurement result based on the distance between the two handles and the number of scissor arms. Specifically:

[0034] The measurement processing unit includes a main controller, a display module, a voice broadcast module, a laser rangefinder module, a mode selection module, and a quantity input module.

[0035] The mode selection module is connected to the main controller. The mode selection module can control the calculation processor to switch the corresponding calculation mode according to the state between the measuring foot and the movable frame. The calculation modes include the inner diameter calculation mode and the non-inner diameter calculation mode. When the measuring foot and the movable frame are in a perpendicular state, the mode selection module controls the calculation processor to select the inner diameter calculation mode. When the measuring foot and the movable frame are in a parallel state, the mode selection module controls the calculation processor to select the non-inner diameter calculation mode.

[0036] The quantity input module is connected to the main controller, enabling it to send the accurate number of scissor levers in the device to the main controller. A calculation button is mounted on the handle and connected to the main controller, used to send a start calculation command. A laser ranging module is also mounted on the handle and connected to the main controller. This module measures the distance between the two handles after the main controller receives the start calculation command and sends the distance data to the main controller. Upon receiving the distance data, the main controller calculates the measurement result based on the selected calculation mode and the accurate number of scissor levers. A display module is connected to the main controller to display the measurement result. A voice broadcast module is also connected to the main controller to announce the measurement result.

[0037] In use, the measuring operator first adjusts the position of the measuring feet on both sides of the device and the state between the measuring feet and the movable frame according to the measuring part of the workpiece. Then, the operator switches the calculation mode of the measurement processing unit according to the measuring part. Specifically:

[0038] When measuring the inner diameter of a workpiece, adjust the two measuring feet to be perpendicular to the movable frame and lock them in place using the fasteners. Then, switch the calculation mode of the measurement processing unit to the inner diameter calculation mode using the mode adjustment module. Next, the inspector, holding the two handles in the middle of the device with one hand, inserts the device into the inner hole to be measured. The inspector's hand grips the handles forcefully, causing them to move towards each other. The two scissor-type connecting frames on both sides of the central rod are compressed and extend outward synchronously, driving the movable frames on both sides to move the measuring feet outward and away from each other. When both measuring feet touch the corresponding positions on the inner wall of the inner hole, the inspector sends a start calculation command to the main controller by touching the calculation button with their thumb. Upon receiving the calculation command, the main controller calculates the inner hole measurement result based on the distance data transmitted by the laser ranging module, the selected calculation mode, and the accurate number of the scissor-type rods. The measurement result is then displayed and announced via the screen display module and the voice broadcast module. The inspector can directly obtain the inner hole data based on the data displayed on the screen display module or the result announced by the voice broadcast module.

[0039] When measuring the outer diameter of a workpiece or the distance between two planes, firstly, adjust the position of the measuring feet to the lowest point of the movable frame using the fixed fastener. Then, rotate the measuring feet to extend them downwards, making them perpendicular to the movable frame, and lock them in place using the locking fasteners. Next, use the mode adjustment module to switch the calculation mode of the measurement processing unit to a non-internal diameter calculation mode. Then, the user holds the two handles in the middle of the device with one hand and forces them to move towards each other, causing the two measuring feet to move outwards and away from each other, thus measuring the outer diameter of the workpiece or the distance between two planes. When the inner ends of the two measuring feet... After clamping the outer circle of the workpiece or aligning it with the two planes to be measured, the user sends a start calculation command to the main controller by touching the calculation button with their thumb. Upon receiving the calculation command, the main controller calculates the outer circle diameter or the distance between the two planes based on the distance data transmitted by the laser ranging module, the selected calculation mode, and the accurate number of the shear bar group. The measurement results are then displayed and broadcast via the screen display module and the voice broadcast module. Based on the data displayed on the screen display module or the results broadcast by the voice broadcast module, the inspector can directly obtain the inner hole data.

[0040] Compared with existing measuring devices, the handheld workpiece measuring device provided in this embodiment can adjust the measuring function of the handheld workpiece measuring device by adjusting the state between the measuring feet and the movable frame and changing the calculation mode of the measurement processing unit. This allows it to measure not only the inner diameter of the workpiece, but also the outer diameter of the workpiece and the distance between two planes, thus effectively solving the problem of the single measurement function of existing calipers. After measurement, the measuring personnel can directly obtain the measurement results through the measurement processing unit, making it convenient to use. During use, the number of scissor arms can be added according to the intuitive size of the workpiece, flexibly adjusting the measurement range of the device so that it can be used for measuring workpieces of different sizes. In the natural state, the tension element will drive the two scissor arms to retract towards the central rod, so that the device itself is in a tightened state, which is convenient to carry and store, effectively solving the problem that existing calipers are inconvenient to store and carry due to their own structure.

[0041] Example 2

[0042] The difference between Example 2 and Example 1 is that the measurement processing unit also includes a data storage module connected to the controller for storing the results calculated by the controller. In use, after multiple sets of data measurements are completed, the data recording work can be completed at once by reading the measurement results stored in the storage module, which improves the surveying efficiency.

Claims

1. A handheld workpiece measuring device, characterized in that, The device includes a handheld unit and a measurement processing unit. The handheld unit comprises a central rod, a scissor-type connecting frame, locking fasteners, fixing buckles, measuring feet, and a tension assembly. Handles are symmetrically fitted at the upper and lower ends of the central rod, and both handles can slide up and down along the central guide rod. Movable frames are symmetrically arranged on the left and right sides of the central rod, parallel to each other. Two connecting seats are vertically spaced on each movable frame, and both connecting seats can slide vertically along the movable frame. Measuring feet are hinged to the end of each movable frame away from the central rod via fixing buckles, and the position of the measuring feet on the movable frame can be adjusted by the fixing buckles. Locking fasteners are fitted onto the fixing buckles, locking the measuring feet to maintain a parallel or perpendicular state with the movable frame. Each movable frame is connected to the central rod... Each rod is equipped with a scissor-type connecting frame, which includes multiple scissor rod groups arranged laterally. Adjacent scissor rod groups are hinged together. The two ends of the scissor rod group on the side adjacent to the movable frame are hinged to the corresponding connecting seats. The two ends of the scissor rod group on the side adjacent to the central rod are hinged to the upper and lower handles. The scissor connecting frames on both sides of the central rod are connected by tension members, which, in their natural state, will drive the two scissor connecting frames to retract towards the central rod. The measurement and processing unit is matched and installed on the handle. After the measurement and processing unit selects the corresponding calculation mode according to the state between the measuring foot and the movable frame, the measurement and processing unit can automatically calculate the measurement result based on the distance between the two handles and the number of scissor rod groups. The measurement processing unit includes a main controller, a display module, a voice broadcast module, a laser ranging module, a mode selection module, and a quantity input module. The mode selection module is connected to the main controller and can control the calculation processor to switch the corresponding calculation mode according to the state between the measuring foot and the movable frame. The quantity input module is connected to the main controller and is used to send the accurate quantity of the scissor pole group in the device to the main controller. The calculation button is matched and set on the handle and connected to the main controller. It is used to send the start calculation command to the main controller. The laser rangefinder module is matched and set on the handle and connected to the main controller. It is used to measure the distance between the two handles after the main controller receives the start calculation command and send the distance data to the main controller. After receiving the distance data between the two handles, the main controller will calculate the measurement result according to the selected calculation mode and the accurate number of the scissor arms. The calculation modes include an inner diameter calculation mode and a non-inner diameter calculation mode. When the measuring foot is perpendicular to the movable frame, the calculation processor is controlled by the mode selection module to select the inner diameter calculation mode. When the measuring foot is parallel to the movable frame, the calculation processor is controlled by the mode selection module to select the non-inner diameter calculation mode.

2. The handheld workpiece measuring device according to claim 1, characterized in that, The center rod has a vertical groove extending backward through the rod body in the middle, and two sliding rods are arranged vertically at intervals in the groove, and the sliding rods can slide vertically along the groove; the handle has a vertical insertion hole in the middle that matches the center rod, and is fitted onto the center rod and connected to the adjacent sliding rod.

3. The handheld workpiece measuring device according to claim 1, characterized in that, The movable frame has multiple insertion holes evenly spaced vertically at one end away from the central rod. The inner end of the fixing buckle has a slot that matches the thickness of the movable frame, and the front and rear side walls of the slot are matched with external insertion holes that match the insertion holes. When the slot end of the fixing buckle is inserted into the movable frame so that the external insertion hole overlaps with the insertion hole, the fixing buckle is fixed together with the movable frame by a pin.

4. The handheld workpiece measuring device according to claim 1, characterized in that, The fixed buckle has a vertically extending hinge groove at the end away from the movable frame. The root of the measuring foot is matched and installed in the hinge groove by a pin, and the measuring foot can rotate around the hinge groove. The measuring foot can be locked in the hinge groove by a locking fastener.

5. The handheld workpiece measuring device according to claim 4, characterized in that, The locking device includes a fixing pin arranged longitudinally. The end of the fixing buckle away from the movable frame has two positioning holes with the pin at the root of the probe as the center, spaced circumferentially along the hinge groove. The root of the probe is matched with an inner insertion hole corresponding to the two positioning grooves. When the inner insertion hole overlaps with the positioning hole, inserting the pin can lock the probe to the movable buckle. When the inner insertion hole at the root of the probe coincides with the first positioning hole, the probe and the movable frame are in a parallel state. When the inner insertion hole at the root of the probe coincides with the second positioning hole, the probe and the movable frame are in a perpendicular state.

6. The handheld workpiece measuring device according to claim 1, characterized in that, The tension component includes return springs symmetrically arranged on the front and rear sides of the central rod. The left and right ends of the return springs are respectively connected to the middle pins of the adjacent scissor rod groups of the left and right scissor connecting frames. In the natural state, the return springs will drive the two scissor connecting frames to retract towards the central rod side.

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