CN2237839Y - Adjustable stiffness pointer type volute spring balance - Google Patents

Abstract

The utility model relates to a pointer type volute spring balance with adjustable stiffness, which is a balance using the elastic deformation of a volute spring for weighing and is mainly composed of a balance casing (3), the volute spring (5), a torque disk (7), flexible ropes (6), (8), a pointer (14) and a graduated disk (16). The utility model is characterized in that the flexible ropes are tensioned by the gravity of an object to drive the torque disk and the pointer to rotate and tightly wind the volute spring and under a standstill condition the pointed graduation is the weight of the object. The balance has the advantages of adjustable efficient working length of the volute spring, adjustable rigidity, error correction, small volume, high precision, visual weighing, and convenient carrying, and is suitable for buyers and sellers at markets and travellers.

Description

A kind of adjustable rigidity pointer-type volute spring balance

The utility model is a kind of scale that carries out weighing about the elastic deformation of utilizing spiral spring to produce.

Existing scale generally is extension spring direct slide spring balance or steelyard.The former is owing to be subjected to the restriction of design itself, volume can not be very little, have to do the scale body very long for dividing thin scale, inconvenience is carried, and because of the weighing that the extension spring stiffness change produces is forbidden and can't be eliminated, though latter's weighing precision height because the arm beam of steelyard is long and need use sliding weight of steelyard, so weighing, carry convenient inadequately.

It is a kind of with pointer indication that the utility model provides, and index dial is a garden shape, and volume is less, the volute spring balance that precision is higher, and its reading is more directly perceived, has the function of correction error.

Its solution is; The outer end of one or several spiral springs is fixed on the inwall of shell, the inner is fixed on the moment dish, the moment dish is fixed on the mandrel, mandrel is also rotatable on shell with rolling or sliding supported condition, the mandrel front end is fixed with pointer, and pointer refers to that on index dial index dial is pressed on the shell, be wound with flexible strand on the moment dish, flexible strand one end is fixed on the moment dish, an end pass rope hole on the shell be steelyard hook.

When the steelyard hook hook has article, the gravity tensioning flexible strand of article, drive the moment disc spins, mandrel and pointer rotate synchronously simultaneously, the rotation of moment dish makes the spiral spring rolling-in, and the spiral spring of rolling-in produces moment loading on the moment dish because of elastic deformation takes place, and the moment direction that produces on the moment dish with the gravity of article is opposite, when these two equalising torques, the scale of pointer indication is the weight of article.

By changing effective active length of spiral spring, thereby scalable rigidity, proofreading and correct spiral spring produces small plastic yield or causes the small stiffness change of spiral spring because of the variation of temperature because of stressed repeatedly, make weighing accurate, prolong the serviceable life of spiral spring simultaneously, enlarged the margin tolerance of spiral spring rigidity value aborning.

The scale handle is equipped with on the top of shell, when outer casing underpart is equipped with trundle when the weighing article to corresponding position with scale, flexible strand is passed rope aperture on the shell and is crossed this side of taking turns and be drawn out, the active line of article gravity passes through the center and the scale handle of shell simultaneously, when weighing, make scale keep center position like this, make things convenient for weighing and reading.

Enlarge range of weighing of the present utility model as need, can on the moment dish, have the race of several different-diameters, the flexible strand of steelyard hook is respectively arranged around a root system in the race, can enlarge range of weighing exponentially like this.

The utility model compare with other mechanical scale have that volume is little, weighing is accurately convenient, big, cheap, the correctable advantage of error of range, is applicable to that the trafficker both sides of country trade and tourist use.

Accompanying drawing 1, accompanying drawing 2 and accompanying drawing 3 have been described an example of the present utility model.

Fig. 1 is the profile front view of scale.

Fig. 2 is that cut-open view is looked on the left side of scale

Fig. 3 is the back side cut-open view of scale

More than among each figure:

1, scale 2, scale is screw 3, scale shell 4, cover plate 5, spiral spring 6, red flexible strand 7, moment dish 8, green flexible strand 9, cover screw 10, trundle 11, bearing pin 12, circlip 13, glass lid 14, pointer 15, mandrel 16, index dial 17, trim ring 18, pressure spring plate 19, pull-out piece spring screw 20, steelyard hook.

With reference to each figure: the inner of spiral spring [5] is fixed on the moment dish [7] by crotch, the crotch of outer end is through in the aperture of relevant position of scale shell [3], pressure spring plate [18] is pressed on the spiral spring silk of close outer end of spiral spring [5], one circumferential elongated slot is arranged on scale shell [3] wall, pull-out piece spring screw [19] is through in this elongated slot, connect with pressure spring plate [18] by screw thread, the spiral spring silk near the outer end is pressed on the inwall of scale shell [3].Moment dish [7] is fastened on the mandrel [15], mandrel [15] is supported in the hole at scale shell [3] and cover plate [4] center and rotatable (scale shell [3] and cover plate [4] are collectively referred to as shell), mandrel [15] front end is equipped with pointer [14] and refers on index dial [16], this spring balance has two ranges, the race that two different-diameters are arranged on moment dish [7], in two races, be wound with flexible strand [6] and [8] respectively, the inner of these two flexible strand is fixed on the wheel cell wall, the outer end pass rope hole on the scale shell [3] respectively be a steelyard hook [20].Circlip [12] is pressed on index dial [16], trim ring [17], glass lid [13] on the scale shell [3].Cover plate [4] is fastened on the scale shell [3] with cover screw [9].Trundle [10] is through on the bearing pin [11], and bearing pin [11] is fastened on the scale shell [3].This example sees that from the front direction that pointer [14] turns clockwise is the direction that scale value increases.

This scale is work like this: when portable firmly scale handle [1], and when on steelyard hook [20], hooking weight, weight adds a moment of face by flexible strand [6] or [8] to moment dish [7], thereby moment dish [7] just rotates with respect to scale shell [3], simultaneously steelyard hook [20] and flexible strand [6] or [8] the rope hole of passing scale shell [3] is drawn out along a side of trundle [10], when moment of face and spiral spring equate because of counter torque that elastic deformation produces takes place in rolling-in, promptly no longer relatively rotate between moment dish [7] and the scale shell [3] and be in equilibrium state, at this moment the scale of pointer [14] indication is weight of heavy.

This scale is to regulate like this: when steelyard hook [20] when not hanging weight, write down the scale value A of pointer [14] indication at this moment, on steelyard hook [20], hang up the weight of a known weight then, and write down the scale value 8 of pointer [14] indication at this moment, heavy as difference (8-A) greater than thing, the rigidity value that spiral spring [5] then is described is less than normal, must transfer the rigidity value of spiral spring [5] big, can unclamp pull-out piece spring screw [19], the direction that increases along scale value in the circumferential elongated slot of scale shell [3] moves pull-out piece spring screw [19] one segment distances, and then tighten pull-out piece spring screw [19], press the preceding method weighing again, till difference (8-A) equals the thing weight; Heavy as difference (8-A) less than thing, illustrate that the rigidity value of spiral spring [5] is bigger than normal, the rigidity value of spiral spring [5] must be turned down, then press with aforementioned reverse direction and regulate pull-out piece spring screw [19], and it is heavy to make difference (8-A) equal thing.After difference (8-A) and thing heavy phase etc., take out circlip [12], glass lid [13], trim ring [17], rotary dial [16] makes it zero-bit and overlaps with the pointer zero-bit, the part of pulling down is assembled to get final product again.

Claims (4)

1, a kind of adjustable rigidity pointer-type volute spring balance, by scale shell [3], spiral spring [3], glass lid [13], pointer [14], index dial [16], steelyard hook compositions such as [20], it is characterized in that: the outer end of spiral spring [5] is fixed on the inwall of scale shell [3], the inner is fixed on the moment dish [7], moment dish [7] is fixed on the mandrel [15], mandrel [15] is supported in the shell by rolling or sliding bearing and turns, mandrel [15] front end is fixed with pointer [14], pointer [14] refers on index dial [16], index dial [16] is pressed on the scale shell [3], be wound with flexible strand [6] or [8] on the moment dish [7], the inner of flexible strand [6] or [8] is fixed on the wheel cell wall of moment dish [7], and there is steelyard hook [20] in the rope hole system that scale shell [3] is passed in the outer end; Effective active length of spiral spring [5] can be regulated, thereby can finely tune the rigidity correction error.

2, by the described scale of claim 1, it is characterized in that shell upper is equipped with scale [1], trundle [10] is housed, after rope hole on the scale shell [3] is passed in flexible strand [6] or [8] in position that outer casing underpart is corresponding with scale handle [1], promptly the side along trundle [10] is drawn out, and makes things convenient for weighing and reading.

3, by the described scale of claim 1, it is characterized in that on [7] on the moment dish, having the race of several different-diameters, the flexible strand of steelyard hook [20] is respectively arranged around a root system on the race, so just form multiple range scale.

4,, it is characterized in that index dial [16] is rotatable after unclamping circlip [12], glass lid [13], trim ring [17], and can return to zero by the described scale of claim 1.

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