A clamping device for thin-walled workpieces

Abstract

The present invention discloses a clamping device for thin-walled workpieces, which includes a housing clamping part, a housing adjusting part, a part clamping part and a part adjusting part. The housing adjusting part includes a first adjusting member, and the first adjusting member can control the first housing clamping seat and the second housing clamping seat to approach or move away from each other. The part adjusting part includes a second adjusting member, and the second adjusting member can control the first part clamping block and the second part clamping block to approach or move away from each other. The housing clamping part further includes a first elastic member, and the part clamping part further includes a second elastic member. By adopting the present invention, it is possible to clamp the thin-walled housing and the thin-walled part to be assembled, and the clamping force is adjustable, which can effectively protect the thin-walled workpiece and has a wide range of applications.

Description

Technical Field

[0001] The present invention relates to the technical field of clamping devices, and particularly to a clamping device for thin-walled workpieces. Background Art

[0002] Existing thin-walled parts such as copper tubes often need to be assembled with thin-walled shells such as plastic or sheet metal shells. During the process of automated production, if the clamping force for holding the thin-walled parts and the plastic shells is too large, due to the poor rigidity and low strength of the thin-walled parts and the thin-walled shells, the thin-walled parts or the plastic shells are extremely likely to be deformed by force during the assembly process. If the applied clamping force is too small, relative displacement of the thin-walled parts or the plastic shells may occur during the assembly process, thus affecting the assembly accuracy of the two and reducing the production efficiency. Therefore, it is necessary to clamp both the thin-walled shells and the thin-walled parts with a device having a variable clamping force to improve the product quality and production efficiency. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a clamping device for thin-walled workpieces, which can clamp the thin-walled shells and thin-walled parts to be assembled, and the clamping force is adjustable, so as to effectively protect the thin-walled workpieces.

[0004] To solve the above technical problem, the present invention provides a clamping device for thin-walled workpieces, which is used to hold a thin-walled shell and a thin-walled part cooperating with the thin-walled shell for subsequent assembly of the thin-walled part, and includes a shell clamping part, a shell adjusting part, a part clamping part and a part adjusting part. The shell clamping part and the part clamping part are connected and are respectively used to hold the thin-walled shell and the thin-walled part.

[0005] The shell clamping part includes a first shell clamping seat and a second shell clamping seat, and the first shell clamping seat and the second shell clamping seat can hold the thin-walled shell from both sides.

[0006] The shell adjusting part includes a first adjusting member, and the first adjusting member can control the first shell clamping seat and the second shell clamping seat to approach or move away from each other.

[0007] The part clamping part includes a first part clamping block and a second part clamping block, and the first part clamping block and the second part clamping block can hold the thin-walled part from both sides.

[0008] The part adjusting part includes a second adjusting member, and the second adjusting member can control the first part clamping block and the second part clamping block to approach or move away from each other.

[0009] Among them, the outer shell clamping part further includes a first elastic member, and both ends of the first elastic member are respectively located between the first outer shell clamping seat and the second outer shell clamping seat, and are used to make the first outer shell clamping seat and the second outer shell clamping seat have a tendency to approach each other.

[0010] The part clamping part further includes a second elastic member, and both ends of the second elastic member are respectively located between the first part clamping block and the second part clamping block, and are used to make the first part clamping block and the second part clamping block have a tendency to approach each other

[0011] Among them, the first adjusting member is located below the first outer shell clamping seat and the second outer shell clamping seat, and the first adjusting member has two opposite first inclined surfaces that gradually approach upward.

[0012] The second adjusting member is located above the first part clamping block and the second part clamping block, and the second adjusting member has two opposite second inclined surfaces that gradually approach upward.

[0013] Among them, the outer shell adjusting part further includes a first adjusting arm, the first adjusting arm is respectively fixed below the first outer shell clamping seat and the second outer shell clamping seat, and first rollers are provided at the bottom of the first adjusting arm, and the rolling surfaces of the first rollers can respectively contact the two first inclined surfaces.

[0014] The part adjusting part further includes a second adjusting arm, the second adjusting arm is respectively fixed to one end of the first part clamping block and the second part clamping block close to the second adjusting member, and second rollers are provided at the bottom of the second adjusting arm, and the rolling surfaces of the second rollers can respectively contact the second inclined surfaces.

[0015] Among them, the outer shell adjusting part further includes a first buffer block, the first buffer block is arranged on the side of the first adjusting arm, and first buffer pads are provided on both sides of the first buffer block.

[0016] The part adjusting part further includes a second buffer block, the second buffer block is arranged between the first part clamping block and the second part clamping block, and second buffer pads are provided on both sides of the second buffer block.

[0017] Among them, the outer shell adjusting part further includes a first threaded rod, the first threaded rod is respectively fixed on both sides of the first adjusting arm, the rod part of the first threaded rod is parallel to the moving direction of the first outer shell clamping seat and the second outer shell clamping seat, and the end of the first threaded rod can contact the first buffer pad.

[0018] Among them, the part adjusting portion further includes a second threaded rod, which is respectively fixed to one side of the first part clamping block and the second part clamping block. The rod portion of the second threaded rod is parallel to the moving direction of the first part clamping block and the second part clamping block, and the end portion of the second threaded rod can contact the second buffer pad.

[0019] Among them, the housing adjusting portion further includes a first lifting mechanism, which is connected to the first adjusting member, and the first lifting mechanism can control the first adjusting member to lift in the vertical direction.

[0020] The part adjusting portion further includes a second lifting mechanism, which is connected to the second adjusting member, and the second lifting mechanism can control the second adjusting member to lift in the vertical direction.

[0021] Among them, the thin-walled workpiece clamping device further includes a sliding seat, and the first housing clamping seat and the second housing clamping seat can slide on one side of the sliding seat, and the first part clamping rod and the second part clamping rod can slide on the other side of the sliding seat.

[0022] Among them, the first elastic member and the second elastic member are tension springs.

[0023] Implementing the present invention has the following beneficial effects:

[0024] The thin-walled workpiece clamping device of the present invention is provided with a housing clamping portion, a housing adjusting portion, a part clamping portion and a part adjusting portion. Among them, the first housing clamping seat and the second housing clamping seat of the housing clamping portion are used to clamp the thin-walled housing to fix it, and the first adjusting member in the housing adjusting portion can control the first housing clamping seat and the second housing clamping seat to approach or move away from each other, so as to control the magnitude of the clamping force received by the thin-walled housing. Similarly, the second adjusting member can control the first part clamping block and the second part clamping block to approach or move away from each other, so as to control the magnitude of the clamping force received by the thin-walled part. Therefore, the present invention can clamp the thin-walled housing and the thin-walled part to be assembled, and the clamping force is adjustable, which can effectively protect the thin-walled workpiece and improve the product quality and production efficiency. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of the thin-walled workpiece clamping device of the present invention;

[0026] Figure 2 is a schematic structural diagram of the housing clamping portion and the part clamping portion of the present invention. Detailed Embodiments

[0027] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. It is hereby declared that the directional terms such as up, down, left, right, front, back, inside, and outside that appear or will appear in the text of the present invention are only based on the accompanying drawings of the present invention and do not specifically limit the present invention.

[0028] Referring to Figure 1 , an embodiment of the present invention discloses a clamping device for thin-walled workpieces, which is used to clamp a thin-walled housing 6 and a thin-walled part 7 that cooperates with the thin-walled housing 6, so as to facilitate the subsequent assembly of the thin-walled part 7. The thin-walled part 7 is preferably a thin-walled pipe fitting and needs to be connected to the thin-walled housing 6. The clamping device for thin-walled workpieces includes a housing clamping portion 1, a housing adjusting portion 2, a part clamping portion 3, and a part adjusting portion 4. The housing clamping portion 1 and the part clamping portion 3 are connected and are respectively used to clamp the thin-walled housing 6 and the thin-walled part 7.

[0029] Referring to Figure 2 , the housing clamping portion 1 includes a first housing clamping seat 11 and a second housing clamping seat 12. The first housing clamping seat 11 and the second housing clamping seat 12 can clamp the thin-walled housing 6 from both sides. There is also a supporting seat at the bottom of the first housing clamping seat 11 and the second housing clamping seat 12 to support the thin-walled housing 6. When the first housing clamping seat 11 and the second housing clamping seat 12 move closer to each other, the thin-walled housing 6 can be clamped and fixed on the supporting seat. The housing adjusting portion 2 includes a first adjusting member 21. The first adjusting member 21 can control the first housing clamping seat 11 and the second housing clamping seat 12 to move closer to or away from each other. When the first housing clamping seat 11 and the second housing clamping seat 12 move closer to each other, the clamping force on the thin-walled housing 6 can be increased. When the first housing clamping seat 11 and the second housing clamping seat 12 move away from each other, the clamping force on the thin-walled housing 6 can be reduced. The part clamping portion 3 includes a first part clamping block 31 and a second part clamping block 32. The first part clamping block 31 and the second part clamping block 32 can clamp the thin-walled part 7 from both sides. The part adjusting portion 4 includes a second adjusting member 41. The second adjusting member 41 can control the first part clamping block 31 and the second part clamping block 32 to move closer to or away from each other. Similarly, when the first part clamping block 31 and the second part clamping block 32 move closer to each other, the clamping force on the thin-walled part 7 can be increased. When the first part clamping block 31 and the second part clamping block 32 move away from each other, the clamping force on the thin-walled part 7 can be reduced. Therefore, the present invention can simultaneously clamp the thin-walled housing 6 and the thin-walled part 7 that need to be assembled, and the clamping force is adjustable, which can meet the clamping force requirements of thin-walled housings 6 and thin-walled parts 7 with different hardnesses, effectively protect the thin-walled workpieces, and improve the product quality and production efficiency.

[0030] Specifically, the outer shell clamping portion 1 further includes a first elastic member 13. The two ends of the first elastic member 13 are respectively located between the first outer shell clamping seat 11 and the second outer shell clamping seat 12, and are used to make the first outer shell clamping seat 11 and the second outer shell clamping seat 12 have a tendency to approach each other, so as to provide a driving force for the clamping movement of the first outer shell clamping seat 11 and the second outer shell clamping seat 12. The first elastic member 13 is preferably a tension spring, and its two ends are connected to the first outer shell clamping seat 11 and the second outer shell clamping seat 12.

[0031] The first adjusting member 21 is located below the first outer shell clamping seat 11 and the second outer shell clamping seat 12. The first adjusting member 21 has two opposite first inclined surfaces 211 that gradually approach upward. The first inclined surfaces 211 are used to linearly adjust the clamping force of the first outer shell clamping seat 11 and the second outer shell clamping seat 12. The outer shell adjusting portion 2 further includes a first lifting mechanism 26 and a first adjusting arm 22. The first lifting mechanism 26 is connected to the first adjusting member 21, and the first lifting mechanism 26 can control the first adjusting member 21 to lift in the vertical direction. The first adjusting arm 22 is preferably two, and is respectively fixed below the first outer shell clamping seat 11 and the second outer shell clamping seat 12. The bottom of the first adjusting arm 22 is provided with a first roller 23, and the rolling surfaces of the first rollers 23 can respectively contact the two first inclined surfaces 211. Therefore, the linear adjustment process of the clamping force on the thin-walled outer shell 6 is as follows:

[0032] When it is necessary to reduce the clamping force, the first lifting mechanism 26 controls the first adjusting member 21 to rise and gradually approaches the first rollers 23 below the first outer shell clamping seat 11 and the second outer shell clamping seat 12. Subsequently, the first rollers 23 contact the first inclined surfaces 211 and continue to rise. Since the first inclined surfaces 211 are two opposite inclined surfaces that gradually approach upward, the first inclined surfaces 211 will gradually separate the two first rollers 23 away from each other during the rising process, thereby driving the first outer shell clamping seat 11 and the second outer shell clamping seat 12 to separate away from each other, reducing the clamping force of the first outer shell clamping seat 11 and the second outer shell clamping seat 12. When it is necessary to increase the clamping force, the first adjusting member 21 is controlled to descend, so that the two first rollers 23 approach each other, thereby making the first outer shell clamping seat 11 and the second outer shell clamping seat 12 approach and clamp, achieving the effect of increasing the clamping force.

[0033] The housing adjusting part 2 further includes a first buffer block 24. The first buffer block 24 is arranged on the side of the first adjusting arm 22, and first buffer pads 241 are arranged on both sides of the first buffer block 24. The housing adjusting part 2 further includes a first threaded rod 25. The first threaded rod 25 is respectively fixed on both sides of the first adjusting arm 22. The rod part of the first threaded rod 25 is parallel to the moving direction of the first housing clamping seat 11 and the second housing clamping seat 12. The end of the first threaded rod 25 can contact the buffer pads of the first buffer block 24. The first threaded rod 25 can move with the first housing clamping seat 11 and the second housing clamping seat 12 through the first adjusting arm 22. When the first housing clamping seat 11 and the second housing clamping seat 12 approach each other, that is, when the clamping force is increased, the first threaded rod 25 will touch the first buffer pads 241. Therefore, before the first housing clamping seat 11 and the second housing clamping seat 12 contact and clamp the thin-walled housing 6, the first buffer block 24 bears part of the clamping force from the first housing clamping seat 11 and the second housing clamping seat 12 through the first adjusting arm 22, so that when the first housing clamping seat 11 and the second housing clamping seat 12 contact the thin-walled housing 6, the clamping force is relatively gentle, which can protect the thin-walled housing 6 and thus improve the product quality.

[0034] The part clamping part 3 further includes a second elastic member 33. The two ends of the second elastic member 33 are respectively located between the first part clamping block 31 and the second part clamping block 32, and are used to make the first part clamping block 31 and the second part clamping block 32 have a tendency to approach each other, so as to provide the power for clamping the first part clamping block 31 and the second part clamping block 32. The second elastic member 33 is preferably a tension spring.

[0035] The second adjusting member 41 is located above the first part clamping block 31 and the second part clamping block 32. The second adjusting member 41 has two opposite second inclined surfaces 411 that gradually approach upward. The part adjusting part 4 further includes a second adjusting arm 42. The first adjusting arm 22 is preferably 2, and is respectively fixed to one end of the first part clamping block 31 and the second part clamping block 32 close to the second adjusting member 41. Second rollers 43 are arranged at the bottom of the second adjusting arm 42, and the rolling surfaces of the second rollers 43 can respectively contact the second inclined surfaces 411. The part adjusting part 4 further includes a second lifting mechanism 46. The second lifting mechanism 46 is connected to the second adjusting member 41, and the second lifting mechanism 46 can control the second adjusting member 41 to lift in the vertical direction. The linear adjustment process of the clamping force on the thin-walled part 7 is as follows:

[0036] When it is necessary to reduce the clamping force, the second lifting mechanism 46 controls the second adjusting member 41 to descend and gradually approach the second roller 43 below the first part clamping block 31 and the second part clamping block 32. Subsequently, the second roller 43 contacts the second inclined surface 411 and continues to descend. Since the second inclined surface 411 is composed of two opposite inclined surfaces that gradually approach downward, the second inclined surface 411 will gradually separate the two second rollers 43 during the descending process, thereby driving the first part clamping block 31 and the second part clamping block 32 to separate and move away, reducing the clamping force between the first part clamping block 31 and the second part clamping block 32. When it is necessary to increase the clamping force, the second adjusting member 41 is controlled to ascend, causing the two second rollers 43 to approach each other, so that the first part clamping block 31 and the second part clamping block 32 approach and clamp, achieving the effect of increasing the clamping force.

[0037] The inclination angles of the first inclined surface 211 and the second inclined surface 411 may not be equal. Different inclination angles represent different linear adjustment degrees. The inclination angle of the first inclined surface 211 is larger, making the top of the first adjusting member 21 "sharper". Therefore, the linear adjustment rate of the first adjusting member 21 is faster, and the change in the clamping force is larger. Since the hardness of the thin-walled part 7 is smaller than that of the thin-walled housing 6, the inclination angle of the second inclined surface 411 is smaller than that of the first inclined surface 211, so that the linear adjustment rate of the second adjusting member 41 is slower, and the change in the clamping force is smaller, which can avoid damaging the thin-walled part 7 and can better protect the thin-walled part 7.

[0038] The part adjusting portion 4 further includes a second buffer block 44. The second buffer block 44 is arranged between the first part clamping block 31 and the second part clamping block 32. Second buffer pads 441 are arranged on both sides of the second buffer block 44. The part adjusting portion 4 further includes a second threaded rod 45. The second threaded rod 45 is respectively fixed to one side of the first part clamping block 31 and the second part clamping block 32. The rod portion of the second threaded rod 45 is parallel to the moving direction of the first part clamping block 31 and the second part clamping block 32. The end of the second threaded rod 45 can contact the second buffer pad 441. The second threaded rod 45 can move along with the first part clamping block 31 and the second part clamping block 32. Before clamping the thin-walled part 7, the first part clamping block 31 and the second part clamping block 32 approach each other, and the second threaded rod 45 will first touch the buffer pad of the first buffer block 24 and bear part of the clamping force from the first part clamping block 31 and the second part clamping block 32. Thus, when the first part clamping block 31 and the second part clamping block 32 contact the thin-walled part 7, the clamping force is not large, which can play a role in protecting the thin-walled part 7.

[0039] The thin-walled workpiece clamping device further includes a sliding seat 5. The first housing clamping seat 11 and the second housing clamping seat 12 can slide on one side of the sliding seat 5, and the first part clamping block 31 and the second part clamping block 32 can slide on the other side of the sliding seat 5. The sliding seat 5 connects the first housing clamping seat 11 and the second housing clamping seat 12, as well as the first part clamping block 31 and the second part clamping block 32, so that the clamping of the thin-walled housing 6 and the thin-walled part 7 can be carried out cooperatively.

[0040] The working process of the thin-walled workpiece clamping device of the present invention is as follows:

[0041] Before the thin-walled housing 6 and the thin-walled part 7 arrive, the first lifting mechanism 26 drives the first adjusting member 21 to rise in the direction (upward) of the first housing clamping seat 11 and the second housing clamping seat 12. After the two first rollers 23 contact the first inclined surface 211, they will drive the first housing clamping seat 11 and the second housing clamping seat 12 to gradually move away from each other against the elastic force of the first elastic member 13. At the same time, the second lifting mechanism 46 also drives the second adjusting member 41 to descend in the direction (downward) of the first part clamping block 31 and the second part clamping block 32, and uses the second inclined surface 411 to drive the first part clamping block 31 and the second part clamping block 32 to move away from each other against the elastic force of the second elastic member 33 through the second rollers 43, so that the device is in an open state.

[0042] Subsequently, the thin-walled housing 6 is loaded. First, the thin-walled housing 6 is placed between the first housing clamping seat 11 and the second housing clamping seat 12. At this time, the first lifting mechanism 26 drives the first adjusting member 21 to descend. Under the action of the first elastic member 13, the first housing clamping seat 11 and the second housing clamping seat 12 approach. When the first threaded rod 25 contacts the first buffer pad 241 for buffering, the first housing clamping seat 11 and the second housing clamping seat 12 continue to approach the thin-walled housing 6 and clamp and hold it tightly.

[0043] After that, the thin-walled part 7 is loaded. The thin-walled part 7 needs to be assembled into the thin-walled housing 6 from top to bottom. At this time, the thin-walled part 7 is placed between the first part clamping block 31 and the second part clamping block 32. Subsequently, the second lifting mechanism 46 drives the second adjusting member 41 to slowly rise. Under the action of the second elastic member 33, the first part clamping block 31 and the second part clamping block 32 slowly approach. After the second threaded rod 45 contacts the second buffer pad 441 for buffering, the first part clamping block 31 and the second part clamping block 32 contact the thin-walled part 7 and clamp and hold it. Then the assembly device will assemble and install the thin-walled part 7 and the thin-walled housing 6.

[0044] In the above process, the first lifting mechanism 26 and the second lifting mechanism 46 can control the speed of the clamping process. The lifting positions of the first adjusting member 21 and the second adjusting member 41 can adjust the magnitude of the clamping force. Moreover, the pre-tightening force can also be adjusted by respectively adjusting the distances between the first threaded rod 25 and the second threaded rod 45 and the first buffer block 24 and the second buffer block 44. Therefore, the embodiment of the present invention can adjust the magnitudes of the clamping force and the pre-tightening force, is applicable to a variety of thin-walled workpieces, and has a wide range of uses.

[0045] The above are the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. A clamping device for thin-walled workpieces, which is used to clamp a thin-walled housing and a thin-walled part that cooperates with the thin-walled housing, so as to facilitate the subsequent assembly of the thin-walled part, and is characterized in that, It includes a housing clamping part, a housing adjusting part, a part clamping part and a part adjusting part. The housing clamping part and the part clamping part are connected and are respectively used for clamping the thin-walled housing and the thin-walled part; The housing clamping part includes a first housing clamping seat and a second housing clamping seat. The first housing clamping seat and the second housing clamping seat can clamp the thin-walled housing from both sides; The housing adjusting part includes a first adjusting member. The first adjusting member can control the first housing clamping seat and the second housing clamping seat to approach or move away from each other; The part clamping part includes a first part clamping block and a second part clamping block. The first part clamping block and the second part clamping block can clamp the thin-walled part from both sides; The part adjusting part includes a second adjusting member. The second adjusting member can control the first part clamping block and the second part clamping block to approach or move away from each other; The housing clamping part further includes a first elastic member. The two ends of the first elastic member are respectively located between the first housing clamping seat and the second housing clamping seat, and are used to make the first housing clamping seat and the second housing clamping seat have a tendency to approach each other; The part clamping part further includes a second elastic member. The two ends of the second elastic member are respectively located between the first part clamping block and the second part clamping block, and are used to make the first part clamping block and the second part clamping block have a tendency to approach each other; The first adjusting member is located below the first housing clamping seat and the second housing clamping seat. The first adjusting member has two opposite first inclined surfaces that gradually approach upward; The second adjusting member is located above the first part clamping block and the second part clamping block. The second adjusting member has two opposite second inclined surfaces that gradually approach upward.

2. The thin-walled workpiece clamping device according to claim 1, wherein The housing adjusting part further includes a first adjusting arm. The first adjusting arm is respectively fixed below the first housing clamping seat and the second housing clamping seat. First rollers are provided at the bottom of the first adjusting arm, and the rolling surfaces of the first rollers can respectively contact the two first inclined surfaces; The part adjusting part further includes a second adjusting arm. The second adjusting arm is respectively fixed to one end of the first part clamping block and the second part clamping block close to the second adjusting member. Second rollers are provided at the bottom of the second adjusting arm, and the rolling surfaces of the second rollers can respectively contact the second inclined surfaces.

3. The thin-walled workpiece clamping device according to claim 2, characterized in that, The housing adjusting part further includes a first buffer block. The first buffer block is provided on the side of the first adjusting arm, and first buffer pads are provided on both sides of the first buffer block; The part adjusting part further includes a second buffer block. The second buffer block is provided between the first part clamping block and the second part clamping block, and second buffer pads are provided on both sides of the second buffer block.

4. The thin-walled workpiece clamping device according to claim 3, characterized in that, The housing adjusting part further includes a first threaded rod. The first threaded rod is respectively fixed on both sides of the first adjusting arm. The rod part of the first threaded rod is parallel to the moving direction of the first housing clamping seat and the second housing clamping seat, and the end of the first threaded rod can contact the first buffer pad.

5. The thin-walled workpiece clamping device according to claim 3, wherein, The part adjusting portion further includes a second threaded rod, the second threaded rod is respectively fixed to one side of the first part clamping block and the second part clamping block, the rod portion of the second threaded rod is parallel to the moving direction of the first part clamping block and the second part clamping block, and the end of the second threaded rod can contact the second buffer pad.

6. The thin-walled workpiece clamping device according to claim 1, characterized in that The housing adjusting portion further includes a first lifting mechanism, the first lifting mechanism is connected to the first adjusting member, and the first lifting mechanism can control the first adjusting member to lift in the vertical direction; The part adjusting portion further includes a second lifting mechanism, the second lifting mechanism is connected to the second adjusting member, and the second lifting mechanism can control the second adjusting member to lift in the vertical direction.

7. The thin-walled workpiece clamping device according to claim 1, wherein, The thin-walled workpiece clamping device further includes a sliding seat, the first housing clamping seat and the second housing clamping seat can slide on one side of the sliding seat, and the first part clamping block and the second part clamping block can slide on the other side of the sliding seat.

8. The thin-walled workpiece clamping device according to claim 1, characterized in that, The first elastic member and the second elastic member are tension springs.

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